diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-16 19:50:13 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-16 19:50:13 -0700 |
commit | 517d08699b250021303f9a7cf0d758b6dc0748ed (patch) | |
tree | 5e5b0134c3fffb78fe9d8b1641a64ff28fdd7bbc /mm | |
parent | 8eeee4e2f04fc551f50c9d9847da2d73d7d33728 (diff) | |
parent | a34601c5d84134055782ee031d58d82f5440e918 (diff) | |
download | op-kernel-dev-517d08699b250021303f9a7cf0d758b6dc0748ed.zip op-kernel-dev-517d08699b250021303f9a7cf0d758b6dc0748ed.tar.gz |
Merge branch 'akpm'
* akpm: (182 commits)
fbdev: bf54x-lq043fb: use kzalloc over kmalloc/memset
fbdev: *bfin*: fix __dev{init,exit} markings
fbdev: *bfin*: drop unnecessary calls to memset
fbdev: bfin-t350mcqb-fb: drop unused local variables
fbdev: blackfin has __raw I/O accessors, so use them in fb.h
fbdev: s1d13xxxfb: add accelerated bitblt functions
tcx: use standard fields for framebuffer physical address and length
fbdev: add support for handoff from firmware to hw framebuffers
intelfb: fix a bug when changing video timing
fbdev: use framebuffer_release() for freeing fb_info structures
radeon: P2G2CLK_ALWAYS_ONb tested twice, should 2nd be P2G2CLK_DAC_ALWAYS_ONb?
s3c-fb: CPUFREQ frequency scaling support
s3c-fb: fix resource releasing on error during probing
carminefb: fix possible access beyond end of carmine_modedb[]
acornfb: remove fb_mmap function
mb862xxfb: use CONFIG_OF instead of CONFIG_PPC_OF
mb862xxfb: restrict compliation of platform driver to PPC
Samsung SoC Framebuffer driver: add Alpha Channel support
atmel-lcdc: fix pixclock upper bound detection
offb: use framebuffer_alloc() to allocate fb_info struct
...
Manually fix up conflicts due to kmemcheck in mm/slab.c
Diffstat (limited to 'mm')
-rw-r--r-- | mm/Kconfig | 14 | ||||
-rw-r--r-- | mm/Makefile | 1 | ||||
-rw-r--r-- | mm/fadvise.c | 2 | ||||
-rw-r--r-- | mm/filemap.c | 169 | ||||
-rw-r--r-- | mm/hugetlb.c | 106 | ||||
-rw-r--r-- | mm/init-mm.c | 20 | ||||
-rw-r--r-- | mm/internal.h | 33 | ||||
-rw-r--r-- | mm/madvise.c | 26 | ||||
-rw-r--r-- | mm/memcontrol.c | 11 | ||||
-rw-r--r-- | mm/memory.c | 128 | ||||
-rw-r--r-- | mm/memory_hotplug.c | 6 | ||||
-rw-r--r-- | mm/mempolicy.c | 145 | ||||
-rw-r--r-- | mm/migrate.c | 6 | ||||
-rw-r--r-- | mm/mlock.c | 22 | ||||
-rw-r--r-- | mm/oom_kill.c | 64 | ||||
-rw-r--r-- | mm/page-writeback.c | 19 | ||||
-rw-r--r-- | mm/page_alloc.c | 754 | ||||
-rw-r--r-- | mm/page_io.c | 2 | ||||
-rw-r--r-- | mm/readahead.c | 145 | ||||
-rw-r--r-- | mm/rmap.c | 40 | ||||
-rw-r--r-- | mm/shmem.c | 4 | ||||
-rw-r--r-- | mm/slab.c | 11 | ||||
-rw-r--r-- | mm/slob.c | 4 | ||||
-rw-r--r-- | mm/slub.c | 2 | ||||
-rw-r--r-- | mm/swap_state.c | 17 | ||||
-rw-r--r-- | mm/swapfile.c | 276 | ||||
-rw-r--r-- | mm/truncate.c | 39 | ||||
-rw-r--r-- | mm/util.c | 16 | ||||
-rw-r--r-- | mm/vmscan.c | 372 | ||||
-rw-r--r-- | mm/vmstat.c | 19 |
30 files changed, 1598 insertions, 875 deletions
@@ -203,25 +203,13 @@ config VIRT_TO_BUS def_bool y depends on !ARCH_NO_VIRT_TO_BUS -config UNEVICTABLE_LRU - bool "Add LRU list to track non-evictable pages" - default y - help - Keeps unevictable pages off of the active and inactive pageout - lists, so kswapd will not waste CPU time or have its balancing - algorithms thrown off by scanning these pages. Selecting this - will use one page flag and increase the code size a little, - say Y unless you know what you are doing. - - See Documentation/vm/unevictable-lru.txt for more information. - config HAVE_MLOCK bool default y if MMU=y config HAVE_MLOCKED_PAGE_BIT bool - default y if HAVE_MLOCK=y && UNEVICTABLE_LRU=y + default y if HAVE_MLOCK=y config MMU_NOTIFIER bool diff --git a/mm/Makefile b/mm/Makefile index c379ce0..5e0bd64 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -12,6 +12,7 @@ obj-y := bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \ readahead.o swap.o truncate.o vmscan.o shmem.o \ prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \ page_isolation.o mm_init.o $(mmu-y) +obj-y += init-mm.o obj-$(CONFIG_PROC_PAGE_MONITOR) += pagewalk.o obj-$(CONFIG_BOUNCE) += bounce.o diff --git a/mm/fadvise.c b/mm/fadvise.c index 54a0f80..e433592 100644 --- a/mm/fadvise.c +++ b/mm/fadvise.c @@ -101,7 +101,7 @@ SYSCALL_DEFINE(fadvise64_64)(int fd, loff_t offset, loff_t len, int advice) ret = force_page_cache_readahead(mapping, file, start_index, - max_sane_readahead(nrpages)); + nrpages); if (ret > 0) ret = 0; break; diff --git a/mm/filemap.c b/mm/filemap.c index 1b60f30..2239671 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -521,7 +521,7 @@ struct page *__page_cache_alloc(gfp_t gfp) { if (cpuset_do_page_mem_spread()) { int n = cpuset_mem_spread_node(); - return alloc_pages_node(n, gfp, 0); + return alloc_pages_exact_node(n, gfp, 0); } return alloc_pages(gfp, 0); } @@ -1004,9 +1004,6 @@ EXPORT_SYMBOL(grab_cache_page_nowait); static void shrink_readahead_size_eio(struct file *filp, struct file_ra_state *ra) { - if (!ra->ra_pages) - return; - ra->ra_pages /= 4; } @@ -1390,8 +1387,7 @@ do_readahead(struct address_space *mapping, struct file *filp, if (!mapping || !mapping->a_ops || !mapping->a_ops->readpage) return -EINVAL; - force_page_cache_readahead(mapping, filp, index, - max_sane_readahead(nr)); + force_page_cache_readahead(mapping, filp, index, nr); return 0; } @@ -1457,6 +1453,73 @@ static int page_cache_read(struct file *file, pgoff_t offset) #define MMAP_LOTSAMISS (100) +/* + * Synchronous readahead happens when we don't even find + * a page in the page cache at all. + */ +static void do_sync_mmap_readahead(struct vm_area_struct *vma, + struct file_ra_state *ra, + struct file *file, + pgoff_t offset) +{ + unsigned long ra_pages; + struct address_space *mapping = file->f_mapping; + + /* If we don't want any read-ahead, don't bother */ + if (VM_RandomReadHint(vma)) + return; + + if (VM_SequentialReadHint(vma) || + offset - 1 == (ra->prev_pos >> PAGE_CACHE_SHIFT)) { + page_cache_sync_readahead(mapping, ra, file, offset, + ra->ra_pages); + return; + } + + if (ra->mmap_miss < INT_MAX) + ra->mmap_miss++; + + /* + * Do we miss much more than hit in this file? If so, + * stop bothering with read-ahead. It will only hurt. + */ + if (ra->mmap_miss > MMAP_LOTSAMISS) + return; + + /* + * mmap read-around + */ + ra_pages = max_sane_readahead(ra->ra_pages); + if (ra_pages) { + ra->start = max_t(long, 0, offset - ra_pages/2); + ra->size = ra_pages; + ra->async_size = 0; + ra_submit(ra, mapping, file); + } +} + +/* + * Asynchronous readahead happens when we find the page and PG_readahead, + * so we want to possibly extend the readahead further.. + */ +static void do_async_mmap_readahead(struct vm_area_struct *vma, + struct file_ra_state *ra, + struct file *file, + struct page *page, + pgoff_t offset) +{ + struct address_space *mapping = file->f_mapping; + + /* If we don't want any read-ahead, don't bother */ + if (VM_RandomReadHint(vma)) + return; + if (ra->mmap_miss > 0) + ra->mmap_miss--; + if (PageReadahead(page)) + page_cache_async_readahead(mapping, ra, file, + page, offset, ra->ra_pages); +} + /** * filemap_fault - read in file data for page fault handling * @vma: vma in which the fault was taken @@ -1476,78 +1539,44 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) struct address_space *mapping = file->f_mapping; struct file_ra_state *ra = &file->f_ra; struct inode *inode = mapping->host; + pgoff_t offset = vmf->pgoff; struct page *page; pgoff_t size; - int did_readaround = 0; int ret = 0; size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; - if (vmf->pgoff >= size) + if (offset >= size) return VM_FAULT_SIGBUS; - /* If we don't want any read-ahead, don't bother */ - if (VM_RandomReadHint(vma)) - goto no_cached_page; - /* * Do we have something in the page cache already? */ -retry_find: - page = find_lock_page(mapping, vmf->pgoff); - /* - * For sequential accesses, we use the generic readahead logic. - */ - if (VM_SequentialReadHint(vma)) { - if (!page) { - page_cache_sync_readahead(mapping, ra, file, - vmf->pgoff, 1); - page = find_lock_page(mapping, vmf->pgoff); - if (!page) - goto no_cached_page; - } - if (PageReadahead(page)) { - page_cache_async_readahead(mapping, ra, file, page, - vmf->pgoff, 1); - } - } - - if (!page) { - unsigned long ra_pages; - - ra->mmap_miss++; - + page = find_get_page(mapping, offset); + if (likely(page)) { /* - * Do we miss much more than hit in this file? If so, - * stop bothering with read-ahead. It will only hurt. + * We found the page, so try async readahead before + * waiting for the lock. */ - if (ra->mmap_miss > MMAP_LOTSAMISS) - goto no_cached_page; + do_async_mmap_readahead(vma, ra, file, page, offset); + lock_page(page); - /* - * To keep the pgmajfault counter straight, we need to - * check did_readaround, as this is an inner loop. - */ - if (!did_readaround) { - ret = VM_FAULT_MAJOR; - count_vm_event(PGMAJFAULT); - } - did_readaround = 1; - ra_pages = max_sane_readahead(file->f_ra.ra_pages); - if (ra_pages) { - pgoff_t start = 0; - - if (vmf->pgoff > ra_pages / 2) - start = vmf->pgoff - ra_pages / 2; - do_page_cache_readahead(mapping, file, start, ra_pages); + /* Did it get truncated? */ + if (unlikely(page->mapping != mapping)) { + unlock_page(page); + put_page(page); + goto no_cached_page; } - page = find_lock_page(mapping, vmf->pgoff); + } else { + /* No page in the page cache at all */ + do_sync_mmap_readahead(vma, ra, file, offset); + count_vm_event(PGMAJFAULT); + ret = VM_FAULT_MAJOR; +retry_find: + page = find_lock_page(mapping, offset); if (!page) goto no_cached_page; } - if (!did_readaround) - ra->mmap_miss--; - /* * We have a locked page in the page cache, now we need to check * that it's up-to-date. If not, it is going to be due to an error. @@ -1555,18 +1584,18 @@ retry_find: if (unlikely(!PageUptodate(page))) goto page_not_uptodate; - /* Must recheck i_size under page lock */ + /* + * Found the page and have a reference on it. + * We must recheck i_size under page lock. + */ size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; - if (unlikely(vmf->pgoff >= size)) { + if (unlikely(offset >= size)) { unlock_page(page); page_cache_release(page); return VM_FAULT_SIGBUS; } - /* - * Found the page and have a reference on it. - */ - ra->prev_pos = (loff_t)page->index << PAGE_CACHE_SHIFT; + ra->prev_pos = (loff_t)offset << PAGE_CACHE_SHIFT; vmf->page = page; return ret | VM_FAULT_LOCKED; @@ -1575,7 +1604,7 @@ no_cached_page: * We're only likely to ever get here if MADV_RANDOM is in * effect. */ - error = page_cache_read(file, vmf->pgoff); + error = page_cache_read(file, offset); /* * The page we want has now been added to the page cache. @@ -1595,12 +1624,6 @@ no_cached_page: return VM_FAULT_SIGBUS; page_not_uptodate: - /* IO error path */ - if (!did_readaround) { - ret = VM_FAULT_MAJOR; - count_vm_event(PGMAJFAULT); - } - /* * Umm, take care of errors if the page isn't up-to-date. * Try to re-read it _once_. We do this synchronously, diff --git a/mm/hugetlb.c b/mm/hugetlb.c index e83ad2c..a56e6f3 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -578,41 +578,6 @@ static void free_huge_page(struct page *page) hugetlb_put_quota(mapping, 1); } -/* - * Increment or decrement surplus_huge_pages. Keep node-specific counters - * balanced by operating on them in a round-robin fashion. - * Returns 1 if an adjustment was made. - */ -static int adjust_pool_surplus(struct hstate *h, int delta) -{ - static int prev_nid; - int nid = prev_nid; - int ret = 0; - - VM_BUG_ON(delta != -1 && delta != 1); - do { - nid = next_node(nid, node_online_map); - if (nid == MAX_NUMNODES) - nid = first_node(node_online_map); - - /* To shrink on this node, there must be a surplus page */ - if (delta < 0 && !h->surplus_huge_pages_node[nid]) - continue; - /* Surplus cannot exceed the total number of pages */ - if (delta > 0 && h->surplus_huge_pages_node[nid] >= - h->nr_huge_pages_node[nid]) - continue; - - h->surplus_huge_pages += delta; - h->surplus_huge_pages_node[nid] += delta; - ret = 1; - break; - } while (nid != prev_nid); - - prev_nid = nid; - return ret; -} - static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) { set_compound_page_dtor(page, free_huge_page); @@ -623,6 +588,34 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) put_page(page); /* free it into the hugepage allocator */ } +static void prep_compound_gigantic_page(struct page *page, unsigned long order) +{ + int i; + int nr_pages = 1 << order; + struct page *p = page + 1; + + /* we rely on prep_new_huge_page to set the destructor */ + set_compound_order(page, order); + __SetPageHead(page); + for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { + __SetPageTail(p); + p->first_page = page; + } +} + +int PageHuge(struct page *page) +{ + compound_page_dtor *dtor; + + if (!PageCompound(page)) + return 0; + + page = compound_head(page); + dtor = get_compound_page_dtor(page); + + return dtor == free_huge_page; +} + static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) { struct page *page; @@ -630,7 +623,7 @@ static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) if (h->order >= MAX_ORDER) return NULL; - page = alloc_pages_node(nid, + page = alloc_pages_exact_node(nid, htlb_alloc_mask|__GFP_COMP|__GFP_THISNODE| __GFP_REPEAT|__GFP_NOWARN, huge_page_order(h)); @@ -649,7 +642,7 @@ static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) * Use a helper variable to find the next node and then * copy it back to hugetlb_next_nid afterwards: * otherwise there's a window in which a racer might - * pass invalid nid MAX_NUMNODES to alloc_pages_node. + * pass invalid nid MAX_NUMNODES to alloc_pages_exact_node. * But we don't need to use a spin_lock here: it really * doesn't matter if occasionally a racer chooses the * same nid as we do. Move nid forward in the mask even @@ -875,7 +868,7 @@ static void return_unused_surplus_pages(struct hstate *h, * can no longer free unreserved surplus pages. This occurs when * the nodes with surplus pages have no free pages. */ - unsigned long remaining_iterations = num_online_nodes(); + unsigned long remaining_iterations = nr_online_nodes; /* Uncommit the reservation */ h->resv_huge_pages -= unused_resv_pages; @@ -904,7 +897,7 @@ static void return_unused_surplus_pages(struct hstate *h, h->surplus_huge_pages--; h->surplus_huge_pages_node[nid]--; nr_pages--; - remaining_iterations = num_online_nodes(); + remaining_iterations = nr_online_nodes; } } } @@ -1140,6 +1133,41 @@ static inline void try_to_free_low(struct hstate *h, unsigned long count) } #endif +/* + * Increment or decrement surplus_huge_pages. Keep node-specific counters + * balanced by operating on them in a round-robin fashion. + * Returns 1 if an adjustment was made. + */ +static int adjust_pool_surplus(struct hstate *h, int delta) +{ + static int prev_nid; + int nid = prev_nid; + int ret = 0; + + VM_BUG_ON(delta != -1 && delta != 1); + do { + nid = next_node(nid, node_online_map); + if (nid == MAX_NUMNODES) + nid = first_node(node_online_map); + + /* To shrink on this node, there must be a surplus page */ + if (delta < 0 && !h->surplus_huge_pages_node[nid]) + continue; + /* Surplus cannot exceed the total number of pages */ + if (delta > 0 && h->surplus_huge_pages_node[nid] >= + h->nr_huge_pages_node[nid]) + continue; + + h->surplus_huge_pages += delta; + h->surplus_huge_pages_node[nid] += delta; + ret = 1; + break; + } while (nid != prev_nid); + + prev_nid = nid; + return ret; +} + #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count) { diff --git a/mm/init-mm.c b/mm/init-mm.c new file mode 100644 index 0000000..57aba0d --- /dev/null +++ b/mm/init-mm.c @@ -0,0 +1,20 @@ +#include <linux/mm_types.h> +#include <linux/rbtree.h> +#include <linux/rwsem.h> +#include <linux/spinlock.h> +#include <linux/list.h> +#include <linux/cpumask.h> + +#include <asm/atomic.h> +#include <asm/pgtable.h> + +struct mm_struct init_mm = { + .mm_rb = RB_ROOT, + .pgd = swapper_pg_dir, + .mm_users = ATOMIC_INIT(2), + .mm_count = ATOMIC_INIT(1), + .mmap_sem = __RWSEM_INITIALIZER(init_mm.mmap_sem), + .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock), + .mmlist = LIST_HEAD_INIT(init_mm.mmlist), + .cpu_vm_mask = CPU_MASK_ALL, +}; diff --git a/mm/internal.h b/mm/internal.h index 987bb03..f290c4d 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -16,9 +16,6 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma, unsigned long floor, unsigned long ceiling); -extern void prep_compound_page(struct page *page, unsigned long order); -extern void prep_compound_gigantic_page(struct page *page, unsigned long order); - static inline void set_page_count(struct page *page, int v) { atomic_set(&page->_count, v); @@ -51,6 +48,8 @@ extern void putback_lru_page(struct page *page); */ extern unsigned long highest_memmap_pfn; extern void __free_pages_bootmem(struct page *page, unsigned int order); +extern void prep_compound_page(struct page *page, unsigned long order); + /* * function for dealing with page's order in buddy system. @@ -74,7 +73,6 @@ static inline void munlock_vma_pages_all(struct vm_area_struct *vma) } #endif -#ifdef CONFIG_UNEVICTABLE_LRU /* * unevictable_migrate_page() called only from migrate_page_copy() to * migrate unevictable flag to new page. @@ -86,11 +84,6 @@ static inline void unevictable_migrate_page(struct page *new, struct page *old) if (TestClearPageUnevictable(old)) SetPageUnevictable(new); } -#else -static inline void unevictable_migrate_page(struct page *new, struct page *old) -{ -} -#endif #ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT /* @@ -150,23 +143,6 @@ static inline void mlock_migrate_page(struct page *newpage, struct page *page) } } -/* - * free_page_mlock() -- clean up attempts to free and mlocked() page. - * Page should not be on lru, so no need to fix that up. - * free_pages_check() will verify... - */ -static inline void free_page_mlock(struct page *page) -{ - if (unlikely(TestClearPageMlocked(page))) { - unsigned long flags; - - local_irq_save(flags); - __dec_zone_page_state(page, NR_MLOCK); - __count_vm_event(UNEVICTABLE_MLOCKFREED); - local_irq_restore(flags); - } -} - #else /* CONFIG_HAVE_MLOCKED_PAGE_BIT */ static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p) { @@ -175,7 +151,6 @@ static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p) static inline void clear_page_mlock(struct page *page) { } static inline void mlock_vma_page(struct page *page) { } static inline void mlock_migrate_page(struct page *new, struct page *old) { } -static inline void free_page_mlock(struct page *page) { } #endif /* CONFIG_HAVE_MLOCKED_PAGE_BIT */ @@ -284,4 +259,8 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, int len, int flags, struct page **pages, struct vm_area_struct **vmas); +#define ZONE_RECLAIM_NOSCAN -2 +#define ZONE_RECLAIM_FULL -1 +#define ZONE_RECLAIM_SOME 0 +#define ZONE_RECLAIM_SUCCESS 1 #endif diff --git a/mm/madvise.c b/mm/madvise.c index b9ce574..76eb419 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -123,8 +123,7 @@ static long madvise_willneed(struct vm_area_struct * vma, end = vma->vm_end; end = ((end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; - force_page_cache_readahead(file->f_mapping, - file, start, max_sane_readahead(end - start)); + force_page_cache_readahead(file->f_mapping, file, start, end - start); return 0; } @@ -239,12 +238,30 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev, break; default: - error = -EINVAL; + BUG(); break; } return error; } +static int +madvise_behavior_valid(int behavior) +{ + switch (behavior) { + case MADV_DOFORK: + case MADV_DONTFORK: + case MADV_NORMAL: + case MADV_SEQUENTIAL: + case MADV_RANDOM: + case MADV_REMOVE: + case MADV_WILLNEED: + case MADV_DONTNEED: + return 1; + + default: + return 0; + } +} /* * The madvise(2) system call. * @@ -290,6 +307,9 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) int write; size_t len; + if (!madvise_behavior_valid(behavior)) + return error; + write = madvise_need_mmap_write(behavior); if (write) down_write(¤t->mm->mmap_sem); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 78eb855..70db6e0 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -570,6 +570,17 @@ int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg) return 0; } +int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg) +{ + unsigned long active; + unsigned long inactive; + + inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_FILE); + active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_FILE); + + return (active > inactive); +} + unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup *memcg, struct zone *zone, enum lru_list lru) diff --git a/mm/memory.c b/mm/memory.c index 4126dd1..d5d1653 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1360,6 +1360,56 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, return i; } +/** + * get_user_pages() - pin user pages in memory + * @tsk: task_struct of target task + * @mm: mm_struct of target mm + * @start: starting user address + * @len: number of pages from start to pin + * @write: whether pages will be written to by the caller + * @force: whether to force write access even if user mapping is + * readonly. This will result in the page being COWed even + * in MAP_SHARED mappings. You do not want this. + * @pages: array that receives pointers to the pages pinned. + * Should be at least nr_pages long. Or NULL, if caller + * only intends to ensure the pages are faulted in. + * @vmas: array of pointers to vmas corresponding to each page. + * Or NULL if the caller does not require them. + * + * Returns number of pages pinned. This may be fewer than the number + * requested. If len is 0 or negative, returns 0. If no pages + * were pinned, returns -errno. Each page returned must be released + * with a put_page() call when it is finished with. vmas will only + * remain valid while mmap_sem is held. + * + * Must be called with mmap_sem held for read or write. + * + * get_user_pages walks a process's page tables and takes a reference to + * each struct page that each user address corresponds to at a given + * instant. That is, it takes the page that would be accessed if a user + * thread accesses the given user virtual address at that instant. + * + * This does not guarantee that the page exists in the user mappings when + * get_user_pages returns, and there may even be a completely different + * page there in some cases (eg. if mmapped pagecache has been invalidated + * and subsequently re faulted). However it does guarantee that the page + * won't be freed completely. And mostly callers simply care that the page + * contains data that was valid *at some point in time*. Typically, an IO + * or similar operation cannot guarantee anything stronger anyway because + * locks can't be held over the syscall boundary. + * + * If write=0, the page must not be written to. If the page is written to, + * set_page_dirty (or set_page_dirty_lock, as appropriate) must be called + * after the page is finished with, and before put_page is called. + * + * get_user_pages is typically used for fewer-copy IO operations, to get a + * handle on the memory by some means other than accesses via the user virtual + * addresses. The pages may be submitted for DMA to devices or accessed via + * their kernel linear mapping (via the kmap APIs). Care should be taken to + * use the correct cache flushing APIs. + * + * See also get_user_pages_fast, for performance critical applications. + */ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, int len, int write, int force, struct page **pages, struct vm_area_struct **vmas) @@ -3053,22 +3103,13 @@ int in_gate_area_no_task(unsigned long addr) #endif /* __HAVE_ARCH_GATE_AREA */ -#ifdef CONFIG_HAVE_IOREMAP_PROT -int follow_phys(struct vm_area_struct *vma, - unsigned long address, unsigned int flags, - unsigned long *prot, resource_size_t *phys) +static int follow_pte(struct mm_struct *mm, unsigned long address, + pte_t **ptepp, spinlock_t **ptlp) { pgd_t *pgd; pud_t *pud; pmd_t *pmd; - pte_t *ptep, pte; - spinlock_t *ptl; - resource_size_t phys_addr = 0; - struct mm_struct *mm = vma->vm_mm; - int ret = -EINVAL; - - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) - goto out; + pte_t *ptep; pgd = pgd_offset(mm, address); if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd))) @@ -3086,22 +3127,71 @@ int follow_phys(struct vm_area_struct *vma, if (pmd_huge(*pmd)) goto out; - ptep = pte_offset_map_lock(mm, pmd, address, &ptl); + ptep = pte_offset_map_lock(mm, pmd, address, ptlp); if (!ptep) goto out; + if (!pte_present(*ptep)) + goto unlock; + *ptepp = ptep; + return 0; +unlock: + pte_unmap_unlock(ptep, *ptlp); +out: + return -EINVAL; +} +/** + * follow_pfn - look up PFN at a user virtual address + * @vma: memory mapping + * @address: user virtual address + * @pfn: location to store found PFN + * + * Only IO mappings and raw PFN mappings are allowed. + * + * Returns zero and the pfn at @pfn on success, -ve otherwise. + */ +int follow_pfn(struct vm_area_struct *vma, unsigned long address, + unsigned long *pfn) +{ + int ret = -EINVAL; + spinlock_t *ptl; + pte_t *ptep; + + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) + return ret; + + ret = follow_pte(vma->vm_mm, address, &ptep, &ptl); + if (ret) + return ret; + *pfn = pte_pfn(*ptep); + pte_unmap_unlock(ptep, ptl); + return 0; +} +EXPORT_SYMBOL(follow_pfn); + +#ifdef CONFIG_HAVE_IOREMAP_PROT +int follow_phys(struct vm_area_struct *vma, + unsigned long address, unsigned int flags, + unsigned long *prot, resource_size_t *phys) +{ + int ret = -EINVAL; + pte_t *ptep, pte; + spinlock_t *ptl; + + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) + goto out; + + if (follow_pte(vma->vm_mm, address, &ptep, &ptl)) + goto out; pte = *ptep; - if (!pte_present(pte)) - goto unlock; + if ((flags & FOLL_WRITE) && !pte_write(pte)) goto unlock; - phys_addr = pte_pfn(pte); - phys_addr <<= PAGE_SHIFT; /* Shift here to avoid overflow on PAE */ *prot = pgprot_val(pte_pgprot(pte)); - *phys = phys_addr; - ret = 0; + *phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT; + ret = 0; unlock: pte_unmap_unlock(ptep, ptl); out: diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c083cf5..e4412a6 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -422,7 +422,8 @@ int online_pages(unsigned long pfn, unsigned long nr_pages) zone->present_pages += onlined_pages; zone->zone_pgdat->node_present_pages += onlined_pages; - setup_per_zone_pages_min(); + setup_per_zone_wmarks(); + calculate_zone_inactive_ratio(zone); if (onlined_pages) { kswapd_run(zone_to_nid(zone)); node_set_state(zone_to_nid(zone), N_HIGH_MEMORY); @@ -832,6 +833,9 @@ repeat: totalram_pages -= offlined_pages; num_physpages -= offlined_pages; + setup_per_zone_wmarks(); + calculate_zone_inactive_ratio(zone); + vm_total_pages = nr_free_pagecache_pages(); writeback_set_ratelimit(); diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 3eb4a6f..e08e2c4 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -182,13 +182,54 @@ static int mpol_new_bind(struct mempolicy *pol, const nodemask_t *nodes) return 0; } -/* Create a new policy */ +/* + * mpol_set_nodemask is called after mpol_new() to set up the nodemask, if + * any, for the new policy. mpol_new() has already validated the nodes + * parameter with respect to the policy mode and flags. But, we need to + * handle an empty nodemask with MPOL_PREFERRED here. + * + * Must be called holding task's alloc_lock to protect task's mems_allowed + * and mempolicy. May also be called holding the mmap_semaphore for write. + */ +static int mpol_set_nodemask(struct mempolicy *pol, const nodemask_t *nodes) +{ + nodemask_t cpuset_context_nmask; + int ret; + + /* if mode is MPOL_DEFAULT, pol is NULL. This is right. */ + if (pol == NULL) + return 0; + + VM_BUG_ON(!nodes); + if (pol->mode == MPOL_PREFERRED && nodes_empty(*nodes)) + nodes = NULL; /* explicit local allocation */ + else { + if (pol->flags & MPOL_F_RELATIVE_NODES) + mpol_relative_nodemask(&cpuset_context_nmask, nodes, + &cpuset_current_mems_allowed); + else + nodes_and(cpuset_context_nmask, *nodes, + cpuset_current_mems_allowed); + if (mpol_store_user_nodemask(pol)) + pol->w.user_nodemask = *nodes; + else + pol->w.cpuset_mems_allowed = + cpuset_current_mems_allowed; + } + + ret = mpol_ops[pol->mode].create(pol, + nodes ? &cpuset_context_nmask : NULL); + return ret; +} + +/* + * This function just creates a new policy, does some check and simple + * initialization. You must invoke mpol_set_nodemask() to set nodes. + */ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, nodemask_t *nodes) { struct mempolicy *policy; - nodemask_t cpuset_context_nmask; - int ret; pr_debug("setting mode %d flags %d nodes[0] %lx\n", mode, flags, nodes ? nodes_addr(*nodes)[0] : -1); @@ -210,7 +251,6 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, if (((flags & MPOL_F_STATIC_NODES) || (flags & MPOL_F_RELATIVE_NODES))) return ERR_PTR(-EINVAL); - nodes = NULL; /* flag local alloc */ } } else if (nodes_empty(*nodes)) return ERR_PTR(-EINVAL); @@ -221,30 +261,6 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, policy->mode = mode; policy->flags = flags; - if (nodes) { - /* - * cpuset related setup doesn't apply to local allocation - */ - cpuset_update_task_memory_state(); - if (flags & MPOL_F_RELATIVE_NODES) - mpol_relative_nodemask(&cpuset_context_nmask, nodes, - &cpuset_current_mems_allowed); - else - nodes_and(cpuset_context_nmask, *nodes, - cpuset_current_mems_allowed); - if (mpol_store_user_nodemask(policy)) - policy->w.user_nodemask = *nodes; - else - policy->w.cpuset_mems_allowed = - cpuset_mems_allowed(current); - } - - ret = mpol_ops[mode].create(policy, - nodes ? &cpuset_context_nmask : NULL); - if (ret < 0) { - kmem_cache_free(policy_cache, policy); - return ERR_PTR(ret); - } return policy; } @@ -324,6 +340,8 @@ static void mpol_rebind_policy(struct mempolicy *pol, /* * Wrapper for mpol_rebind_policy() that just requires task * pointer, and updates task mempolicy. + * + * Called with task's alloc_lock held. */ void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new) @@ -600,8 +618,9 @@ static void mpol_set_task_struct_flag(void) static long do_set_mempolicy(unsigned short mode, unsigned short flags, nodemask_t *nodes) { - struct mempolicy *new; + struct mempolicy *new, *old; struct mm_struct *mm = current->mm; + int ret; new = mpol_new(mode, flags, nodes); if (IS_ERR(new)) @@ -615,20 +634,33 @@ static long do_set_mempolicy(unsigned short mode, unsigned short flags, */ if (mm) down_write(&mm->mmap_sem); - mpol_put(current->mempolicy); + task_lock(current); + ret = mpol_set_nodemask(new, nodes); + if (ret) { + task_unlock(current); + if (mm) + up_write(&mm->mmap_sem); + mpol_put(new); + return ret; + } + old = current->mempolicy; current->mempolicy = new; mpol_set_task_struct_flag(); if (new && new->mode == MPOL_INTERLEAVE && nodes_weight(new->v.nodes)) current->il_next = first_node(new->v.nodes); + task_unlock(current); if (mm) up_write(&mm->mmap_sem); + mpol_put(old); return 0; } /* * Return nodemask for policy for get_mempolicy() query + * + * Called with task's alloc_lock held */ static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes) { @@ -674,7 +706,6 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask, struct vm_area_struct *vma = NULL; struct mempolicy *pol = current->mempolicy; - cpuset_update_task_memory_state(); if (flags & ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED)) return -EINVAL; @@ -683,7 +714,9 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask, if (flags & (MPOL_F_NODE|MPOL_F_ADDR)) return -EINVAL; *policy = 0; /* just so it's initialized */ + task_lock(current); *nmask = cpuset_current_mems_allowed; + task_unlock(current); return 0; } @@ -738,8 +771,11 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask, } err = 0; - if (nmask) + if (nmask) { + task_lock(current); get_policy_nodemask(pol, nmask); + task_unlock(current); + } out: mpol_cond_put(pol); @@ -767,7 +803,7 @@ static void migrate_page_add(struct page *page, struct list_head *pagelist, static struct page *new_node_page(struct page *page, unsigned long node, int **x) { - return alloc_pages_node(node, GFP_HIGHUSER_MOVABLE, 0); + return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE, 0); } /* @@ -979,6 +1015,14 @@ static long do_mbind(unsigned long start, unsigned long len, return err; } down_write(&mm->mmap_sem); + task_lock(current); + err = mpol_set_nodemask(new, nmask); + task_unlock(current); + if (err) { + up_write(&mm->mmap_sem); + mpol_put(new); + return err; + } vma = check_range(mm, start, end, nmask, flags | MPOL_MF_INVERT, &pagelist); @@ -1545,8 +1589,6 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr) struct mempolicy *pol = get_vma_policy(current, vma, addr); struct zonelist *zl; - cpuset_update_task_memory_state(); - if (unlikely(pol->mode == MPOL_INTERLEAVE)) { unsigned nid; @@ -1593,8 +1635,6 @@ struct page *alloc_pages_current(gfp_t gfp, unsigned order) { struct mempolicy *pol = current->mempolicy; - if ((gfp & __GFP_WAIT) && !in_interrupt()) - cpuset_update_task_memory_state(); if (!pol || in_interrupt() || (gfp & __GFP_THISNODE)) pol = &default_policy; @@ -1854,6 +1894,8 @@ restart: */ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol) { + int ret; + sp->root = RB_ROOT; /* empty tree == default mempolicy */ spin_lock_init(&sp->lock); @@ -1863,9 +1905,19 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol) /* contextualize the tmpfs mount point mempolicy */ new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask); - mpol_put(mpol); /* drop our ref on sb mpol */ - if (IS_ERR(new)) + if (IS_ERR(new)) { + mpol_put(mpol); /* drop our ref on sb mpol */ return; /* no valid nodemask intersection */ + } + + task_lock(current); + ret = mpol_set_nodemask(new, &mpol->w.user_nodemask); + task_unlock(current); + mpol_put(mpol); /* drop our ref on sb mpol */ + if (ret) { + mpol_put(new); + return; + } /* Create pseudo-vma that contains just the policy */ memset(&pvma, 0, sizeof(struct vm_area_struct)); @@ -2086,8 +2138,19 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context) new = mpol_new(mode, mode_flags, &nodes); if (IS_ERR(new)) err = 1; - else if (no_context) - new->w.user_nodemask = nodes; /* save for contextualization */ + else { + int ret; + + task_lock(current); + ret = mpol_set_nodemask(new, &nodes); + task_unlock(current); + if (ret) + err = 1; + else if (no_context) { + /* save for contextualization */ + new->w.user_nodemask = nodes; + } + } out: /* Restore string for error message */ diff --git a/mm/migrate.c b/mm/migrate.c index 068655d8..939888f 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -802,7 +802,7 @@ static struct page *new_page_node(struct page *p, unsigned long private, *result = &pm->status; - return alloc_pages_node(pm->node, + return alloc_pages_exact_node(pm->node, GFP_HIGHUSER_MOVABLE | GFP_THISNODE, 0); } @@ -820,7 +820,6 @@ static int do_move_page_to_node_array(struct mm_struct *mm, struct page_to_node *pp; LIST_HEAD(pagelist); - migrate_prep(); down_read(&mm->mmap_sem); /* @@ -907,6 +906,9 @@ static int do_pages_move(struct mm_struct *mm, struct task_struct *task, pm = (struct page_to_node *)__get_free_page(GFP_KERNEL); if (!pm) goto out; + + migrate_prep(); + /* * Store a chunk of page_to_node array in a page, * but keep the last one as a marker @@ -31,7 +31,6 @@ int can_do_mlock(void) } EXPORT_SYMBOL(can_do_mlock); -#ifdef CONFIG_UNEVICTABLE_LRU /* * Mlocked pages are marked with PageMlocked() flag for efficient testing * in vmscan and, possibly, the fault path; and to support semi-accurate @@ -261,27 +260,6 @@ static int __mlock_posix_error_return(long retval) return retval; } -#else /* CONFIG_UNEVICTABLE_LRU */ - -/* - * Just make pages present if VM_LOCKED. No-op if unlocking. - */ -static long __mlock_vma_pages_range(struct vm_area_struct *vma, - unsigned long start, unsigned long end, - int mlock) -{ - if (mlock && (vma->vm_flags & VM_LOCKED)) - return make_pages_present(start, end); - return 0; -} - -static inline int __mlock_posix_error_return(long retval) -{ - return 0; -} - -#endif /* CONFIG_UNEVICTABLE_LRU */ - /** * mlock_vma_pages_range() - mlock pages in specified vma range. * @vma - the vma containing the specfied address range diff --git a/mm/oom_kill.c b/mm/oom_kill.c index a7b2460..175a67a 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -58,6 +58,7 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) unsigned long points, cpu_time, run_time; struct mm_struct *mm; struct task_struct *child; + int oom_adj; task_lock(p); mm = p->mm; @@ -65,6 +66,11 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) task_unlock(p); return 0; } + oom_adj = mm->oom_adj; + if (oom_adj == OOM_DISABLE) { + task_unlock(p); + return 0; + } /* * The memory size of the process is the basis for the badness. @@ -148,15 +154,15 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) points /= 8; /* - * Adjust the score by oomkilladj. + * Adjust the score by oom_adj. */ - if (p->oomkilladj) { - if (p->oomkilladj > 0) { + if (oom_adj) { + if (oom_adj > 0) { if (!points) points = 1; - points <<= p->oomkilladj; + points <<= oom_adj; } else - points >>= -(p->oomkilladj); + points >>= -(oom_adj); } #ifdef DEBUG @@ -251,11 +257,8 @@ static struct task_struct *select_bad_process(unsigned long *ppoints, *ppoints = ULONG_MAX; } - if (p->oomkilladj == OOM_DISABLE) - continue; - points = badness(p, uptime.tv_sec); - if (points > *ppoints || !chosen) { + if (points > *ppoints) { chosen = p; *ppoints = points; } @@ -304,8 +307,7 @@ static void dump_tasks(const struct mem_cgroup *mem) } printk(KERN_INFO "[%5d] %5d %5d %8lu %8lu %3d %3d %s\n", p->pid, __task_cred(p)->uid, p->tgid, mm->total_vm, - get_mm_rss(mm), (int)task_cpu(p), p->oomkilladj, - p->comm); + get_mm_rss(mm), (int)task_cpu(p), mm->oom_adj, p->comm); task_unlock(p); } while_each_thread(g, p); } @@ -323,11 +325,8 @@ static void __oom_kill_task(struct task_struct *p, int verbose) return; } - if (!p->mm) { - WARN_ON(1); - printk(KERN_WARNING "tried to kill an mm-less task!\n"); + if (!p->mm) return; - } if (verbose) printk(KERN_ERR "Killed process %d (%s)\n", @@ -349,28 +348,13 @@ static int oom_kill_task(struct task_struct *p) struct mm_struct *mm; struct task_struct *g, *q; + task_lock(p); mm = p->mm; - - /* WARNING: mm may not be dereferenced since we did not obtain its - * value from get_task_mm(p). This is OK since all we need to do is - * compare mm to q->mm below. - * - * Furthermore, even if mm contains a non-NULL value, p->mm may - * change to NULL at any time since we do not hold task_lock(p). - * However, this is of no concern to us. - */ - - if (mm == NULL) + if (!mm || mm->oom_adj == OOM_DISABLE) { + task_unlock(p); return 1; - - /* - * Don't kill the process if any threads are set to OOM_DISABLE - */ - do_each_thread(g, q) { - if (q->mm == mm && q->oomkilladj == OOM_DISABLE) - return 1; - } while_each_thread(g, q); - + } + task_unlock(p); __oom_kill_task(p, 1); /* @@ -393,10 +377,11 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, struct task_struct *c; if (printk_ratelimit()) { - printk(KERN_WARNING "%s invoked oom-killer: " - "gfp_mask=0x%x, order=%d, oomkilladj=%d\n", - current->comm, gfp_mask, order, current->oomkilladj); task_lock(current); + printk(KERN_WARNING "%s invoked oom-killer: " + "gfp_mask=0x%x, order=%d, oom_adj=%d\n", + current->comm, gfp_mask, order, + current->mm ? current->mm->oom_adj : OOM_DISABLE); cpuset_print_task_mems_allowed(current); task_unlock(current); dump_stack(); @@ -409,8 +394,9 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, /* * If the task is already exiting, don't alarm the sysadmin or kill * its children or threads, just set TIF_MEMDIE so it can die quickly + * if its mm is still attached. */ - if (p->flags & PF_EXITING) { + if (p->mm && (p->flags & PF_EXITING)) { __oom_kill_task(p, 0); return 0; } diff --git a/mm/page-writeback.c b/mm/page-writeback.c index bb553c3..7b0dcea 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -265,18 +265,19 @@ static void bdi_writeout_fraction(struct backing_dev_info *bdi, * This avoids exceeding the total dirty_limit when the floating averages * fluctuate too quickly. */ -static void -clip_bdi_dirty_limit(struct backing_dev_info *bdi, long dirty, long *pbdi_dirty) +static void clip_bdi_dirty_limit(struct backing_dev_info *bdi, + unsigned long dirty, unsigned long *pbdi_dirty) { - long avail_dirty; + unsigned long avail_dirty; - avail_dirty = dirty - - (global_page_state(NR_FILE_DIRTY) + + avail_dirty = global_page_state(NR_FILE_DIRTY) + global_page_state(NR_WRITEBACK) + global_page_state(NR_UNSTABLE_NFS) + - global_page_state(NR_WRITEBACK_TEMP)); + global_page_state(NR_WRITEBACK_TEMP); - if (avail_dirty < 0) + if (avail_dirty < dirty) + avail_dirty = dirty - avail_dirty; + else avail_dirty = 0; avail_dirty += bdi_stat(bdi, BDI_RECLAIMABLE) + @@ -299,10 +300,10 @@ static inline void task_dirties_fraction(struct task_struct *tsk, * * dirty -= (dirty/8) * p_{t} */ -static void task_dirty_limit(struct task_struct *tsk, long *pdirty) +static void task_dirty_limit(struct task_struct *tsk, unsigned long *pdirty) { long numerator, denominator; - long dirty = *pdirty; + unsigned long dirty = *pdirty; u64 inv = dirty >> 3; task_dirties_fraction(tsk, &numerator, &denominator); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0727896..a5f3c27 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -162,17 +162,25 @@ static unsigned long __meminitdata dma_reserve; #if MAX_NUMNODES > 1 int nr_node_ids __read_mostly = MAX_NUMNODES; +int nr_online_nodes __read_mostly = 1; EXPORT_SYMBOL(nr_node_ids); +EXPORT_SYMBOL(nr_online_nodes); #endif int page_group_by_mobility_disabled __read_mostly; static void set_pageblock_migratetype(struct page *page, int migratetype) { + + if (unlikely(page_group_by_mobility_disabled)) + migratetype = MIGRATE_UNMOVABLE; + set_pageblock_flags_group(page, (unsigned long)migratetype, PB_migrate, PB_migrate_end); } +bool oom_killer_disabled __read_mostly; + #ifdef CONFIG_DEBUG_VM static int page_outside_zone_boundaries(struct zone *zone, struct page *page) { @@ -295,23 +303,6 @@ void prep_compound_page(struct page *page, unsigned long order) } } -#ifdef CONFIG_HUGETLBFS -void prep_compound_gigantic_page(struct page *page, unsigned long order) -{ - int i; - int nr_pages = 1 << order; - struct page *p = page + 1; - - set_compound_page_dtor(page, free_compound_page); - set_compound_order(page, order); - __SetPageHead(page); - for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { - __SetPageTail(p); - p->first_page = page; - } -} -#endif - static int destroy_compound_page(struct page *page, unsigned long order) { int i; @@ -418,7 +409,7 @@ static inline int page_is_buddy(struct page *page, struct page *buddy, return 0; if (PageBuddy(buddy) && page_order(buddy) == order) { - BUG_ON(page_count(buddy) != 0); + VM_BUG_ON(page_count(buddy) != 0); return 1; } return 0; @@ -449,22 +440,22 @@ static inline int page_is_buddy(struct page *page, struct page *buddy, */ static inline void __free_one_page(struct page *page, - struct zone *zone, unsigned int order) + struct zone *zone, unsigned int order, + int migratetype) { unsigned long page_idx; - int order_size = 1 << order; - int migratetype = get_pageblock_migratetype(page); if (unlikely(PageCompound(page))) if (unlikely(destroy_compound_page(page, order))) return; + VM_BUG_ON(migratetype == -1); + page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1); - VM_BUG_ON(page_idx & (order_size - 1)); + VM_BUG_ON(page_idx & ((1 << order) - 1)); VM_BUG_ON(bad_range(zone, page)); - __mod_zone_page_state(zone, NR_FREE_PAGES, order_size); while (order < MAX_ORDER-1) { unsigned long combined_idx; struct page *buddy; @@ -488,12 +479,27 @@ static inline void __free_one_page(struct page *page, zone->free_area[order].nr_free++; } +#ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT +/* + * free_page_mlock() -- clean up attempts to free and mlocked() page. + * Page should not be on lru, so no need to fix that up. + * free_pages_check() will verify... + */ +static inline void free_page_mlock(struct page *page) +{ + __ClearPageMlocked(page); + __dec_zone_page_state(page, NR_MLOCK); + __count_vm_event(UNEVICTABLE_MLOCKFREED); +} +#else +static void free_page_mlock(struct page *page) { } +#endif + static inline int free_pages_check(struct page *page) { - free_page_mlock(page); if (unlikely(page_mapcount(page) | (page->mapping != NULL) | - (page_count(page) != 0) | + (atomic_read(&page->_count) != 0) | (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) { bad_page(page); return 1; @@ -520,6 +526,8 @@ static void free_pages_bulk(struct zone *zone, int count, spin_lock(&zone->lock); zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE); zone->pages_scanned = 0; + + __mod_zone_page_state(zone, NR_FREE_PAGES, count << order); while (count--) { struct page *page; @@ -527,17 +535,20 @@ static void free_pages_bulk(struct zone *zone, int count, page = list_entry(list->prev, struct page, lru); /* have to delete it as __free_one_page list manipulates */ list_del(&page->lru); - __free_one_page(page, zone, order); + __free_one_page(page, zone, order, page_private(page)); } spin_unlock(&zone->lock); } -static void free_one_page(struct zone *zone, struct page *page, int order) +static void free_one_page(struct zone *zone, struct page *page, int order, + int migratetype) { spin_lock(&zone->lock); zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE); zone->pages_scanned = 0; - __free_one_page(page, zone, order); + + __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order); + __free_one_page(page, zone, order, migratetype); spin_unlock(&zone->lock); } @@ -546,6 +557,7 @@ static void __free_pages_ok(struct page *page, unsigned int order) unsigned long flags; int i; int bad = 0; + int clearMlocked = PageMlocked(page); kmemcheck_free_shadow(page, order); @@ -563,8 +575,11 @@ static void __free_pages_ok(struct page *page, unsigned int order) kernel_map_pages(page, 1 << order, 0); local_irq_save(flags); + if (unlikely(clearMlocked)) + free_page_mlock(page); __count_vm_events(PGFREE, 1 << order); - free_one_page(page_zone(page), page, order); + free_one_page(page_zone(page), page, order, + get_pageblock_migratetype(page)); local_irq_restore(flags); } @@ -635,7 +650,7 @@ static int prep_new_page(struct page *page, int order, gfp_t gfp_flags) { if (unlikely(page_mapcount(page) | (page->mapping != NULL) | - (page_count(page) != 0) | + (atomic_read(&page->_count) != 0) | (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) { bad_page(page); return 1; @@ -660,7 +675,8 @@ static int prep_new_page(struct page *page, int order, gfp_t gfp_flags) * Go through the free lists for the given migratetype and remove * the smallest available page from the freelists */ -static struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, +static inline +struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, int migratetype) { unsigned int current_order; @@ -678,7 +694,6 @@ static struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, list_del(&page->lru); rmv_page_order(page); area->nr_free--; - __mod_zone_page_state(zone, NR_FREE_PAGES, - (1UL << order)); expand(zone, page, order, current_order, area, migratetype); return page; } @@ -769,8 +784,8 @@ static int move_freepages_block(struct zone *zone, struct page *page, } /* Remove an element from the buddy allocator from the fallback list */ -static struct page *__rmqueue_fallback(struct zone *zone, int order, - int start_migratetype) +static inline struct page * +__rmqueue_fallback(struct zone *zone, int order, int start_migratetype) { struct free_area * area; int current_order; @@ -818,8 +833,6 @@ static struct page *__rmqueue_fallback(struct zone *zone, int order, /* Remove the page from the freelists */ list_del(&page->lru); rmv_page_order(page); - __mod_zone_page_state(zone, NR_FREE_PAGES, - -(1UL << order)); if (current_order == pageblock_order) set_pageblock_migratetype(page, @@ -830,8 +843,7 @@ static struct page *__rmqueue_fallback(struct zone *zone, int order, } } - /* Use MIGRATE_RESERVE rather than fail an allocation */ - return __rmqueue_smallest(zone, order, MIGRATE_RESERVE); + return NULL; } /* @@ -843,11 +855,23 @@ static struct page *__rmqueue(struct zone *zone, unsigned int order, { struct page *page; +retry_reserve: page = __rmqueue_smallest(zone, order, migratetype); - if (unlikely(!page)) + if (unlikely(!page) && migratetype != MIGRATE_RESERVE) { page = __rmqueue_fallback(zone, order, migratetype); + /* + * Use MIGRATE_RESERVE rather than fail an allocation. goto + * is used because __rmqueue_smallest is an inline function + * and we want just one call site + */ + if (!page) { + migratetype = MIGRATE_RESERVE; + goto retry_reserve; + } + } + return page; } @@ -881,6 +905,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order, set_page_private(page, migratetype); list = &page->lru; } + __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order)); spin_unlock(&zone->lock); return i; } @@ -996,6 +1021,7 @@ static void free_hot_cold_page(struct page *page, int cold) struct zone *zone = page_zone(page); struct per_cpu_pages *pcp; unsigned long flags; + int clearMlocked = PageMlocked(page); kmemcheck_free_shadow(page, 0); @@ -1012,13 +1038,16 @@ static void free_hot_cold_page(struct page *page, int cold) kernel_map_pages(page, 1, 0); pcp = &zone_pcp(zone, get_cpu())->pcp; + set_page_private(page, get_pageblock_migratetype(page)); local_irq_save(flags); + if (unlikely(clearMlocked)) + free_page_mlock(page); __count_vm_event(PGFREE); + if (cold) list_add_tail(&page->lru, &pcp->list); else list_add(&page->lru, &pcp->list); - set_page_private(page, get_pageblock_migratetype(page)); pcp->count++; if (pcp->count >= pcp->high) { free_pages_bulk(zone, pcp->batch, &pcp->list, 0); @@ -1071,14 +1100,15 @@ void split_page(struct page *page, unsigned int order) * we cheat by calling it from here, in the order > 0 path. Saves a branch * or two. */ -static struct page *buffered_rmqueue(struct zone *preferred_zone, - struct zone *zone, int order, gfp_t gfp_flags) +static inline +struct page *buffered_rmqueue(struct zone *preferred_zone, + struct zone *zone, int order, gfp_t gfp_flags, + int migratetype) { unsigned long flags; struct page *page; int cold = !!(gfp_flags & __GFP_COLD); int cpu; - int migratetype = allocflags_to_migratetype(gfp_flags); again: cpu = get_cpu(); @@ -1115,8 +1145,22 @@ again: list_del(&page->lru); pcp->count--; } else { + if (unlikely(gfp_flags & __GFP_NOFAIL)) { + /* + * __GFP_NOFAIL is not to be used in new code. + * + * All __GFP_NOFAIL callers should be fixed so that they + * properly detect and handle allocation failures. + * + * We most definitely don't want callers attempting to + * allocate greater than single-page units with + * __GFP_NOFAIL. + */ + WARN_ON_ONCE(order > 0); + } spin_lock_irqsave(&zone->lock, flags); page = __rmqueue(zone, order, migratetype); + __mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order)); spin_unlock(&zone->lock); if (!page) goto failed; @@ -1138,10 +1182,15 @@ failed: return NULL; } -#define ALLOC_NO_WATERMARKS 0x01 /* don't check watermarks at all */ -#define ALLOC_WMARK_MIN 0x02 /* use pages_min watermark */ -#define ALLOC_WMARK_LOW 0x04 /* use pages_low watermark */ -#define ALLOC_WMARK_HIGH 0x08 /* use pages_high watermark */ +/* The ALLOC_WMARK bits are used as an index to zone->watermark */ +#define ALLOC_WMARK_MIN WMARK_MIN +#define ALLOC_WMARK_LOW WMARK_LOW +#define ALLOC_WMARK_HIGH WMARK_HIGH +#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ + +/* Mask to get the watermark bits */ +#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) + #define ALLOC_HARDER 0x10 /* try to alloc harder */ #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */ #define ALLOC_CPUSET 0x40 /* check for correct cpuset */ @@ -1399,23 +1448,18 @@ static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z) */ static struct page * get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order, - struct zonelist *zonelist, int high_zoneidx, int alloc_flags) + struct zonelist *zonelist, int high_zoneidx, int alloc_flags, + struct zone *preferred_zone, int migratetype) { struct zoneref *z; struct page *page = NULL; int classzone_idx; - struct zone *zone, *preferred_zone; + struct zone *zone; nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */ int zlc_active = 0; /* set if using zonelist_cache */ int did_zlc_setup = 0; /* just call zlc_setup() one time */ - (void)first_zones_zonelist(zonelist, high_zoneidx, nodemask, - &preferred_zone); - if (!preferred_zone) - return NULL; - classzone_idx = zone_idx(preferred_zone); - zonelist_scan: /* * Scan zonelist, looking for a zone with enough free. @@ -1430,31 +1474,49 @@ zonelist_scan: !cpuset_zone_allowed_softwall(zone, gfp_mask)) goto try_next_zone; + BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK); if (!(alloc_flags & ALLOC_NO_WATERMARKS)) { unsigned long mark; - if (alloc_flags & ALLOC_WMARK_MIN) - mark = zone->pages_min; - else if (alloc_flags & ALLOC_WMARK_LOW) - mark = zone->pages_low; - else - mark = zone->pages_high; - if (!zone_watermark_ok(zone, order, mark, - classzone_idx, alloc_flags)) { - if (!zone_reclaim_mode || - !zone_reclaim(zone, gfp_mask, order)) + int ret; + + mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK]; + if (zone_watermark_ok(zone, order, mark, + classzone_idx, alloc_flags)) + goto try_this_zone; + + if (zone_reclaim_mode == 0) + goto this_zone_full; + + ret = zone_reclaim(zone, gfp_mask, order); + switch (ret) { + case ZONE_RECLAIM_NOSCAN: + /* did not scan */ + goto try_next_zone; + case ZONE_RECLAIM_FULL: + /* scanned but unreclaimable */ + goto this_zone_full; + default: + /* did we reclaim enough */ + if (!zone_watermark_ok(zone, order, mark, + classzone_idx, alloc_flags)) goto this_zone_full; } } - page = buffered_rmqueue(preferred_zone, zone, order, gfp_mask); +try_this_zone: + page = buffered_rmqueue(preferred_zone, zone, order, + gfp_mask, migratetype); if (page) break; this_zone_full: if (NUMA_BUILD) zlc_mark_zone_full(zonelist, z); try_next_zone: - if (NUMA_BUILD && !did_zlc_setup) { - /* we do zlc_setup after the first zone is tried */ + if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) { + /* + * we do zlc_setup after the first zone is tried but only + * if there are multiple nodes make it worthwhile + */ allowednodes = zlc_setup(zonelist, alloc_flags); zlc_active = 1; did_zlc_setup = 1; @@ -1469,47 +1531,217 @@ try_next_zone: return page; } +static inline int +should_alloc_retry(gfp_t gfp_mask, unsigned int order, + unsigned long pages_reclaimed) +{ + /* Do not loop if specifically requested */ + if (gfp_mask & __GFP_NORETRY) + return 0; + + /* + * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER + * means __GFP_NOFAIL, but that may not be true in other + * implementations. + */ + if (order <= PAGE_ALLOC_COSTLY_ORDER) + return 1; + + /* + * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is + * specified, then we retry until we no longer reclaim any pages + * (above), or we've reclaimed an order of pages at least as + * large as the allocation's order. In both cases, if the + * allocation still fails, we stop retrying. + */ + if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order)) + return 1; + + /* + * Don't let big-order allocations loop unless the caller + * explicitly requests that. + */ + if (gfp_mask & __GFP_NOFAIL) + return 1; + + return 0; +} + +static inline struct page * +__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, + struct zonelist *zonelist, enum zone_type high_zoneidx, + nodemask_t *nodemask, struct zone *preferred_zone, + int migratetype) +{ + struct page *page; + + /* Acquire the OOM killer lock for the zones in zonelist */ + if (!try_set_zone_oom(zonelist, gfp_mask)) { + schedule_timeout_uninterruptible(1); + return NULL; + } + + /* + * Go through the zonelist yet one more time, keep very high watermark + * here, this is only to catch a parallel oom killing, we must fail if + * we're still under heavy pressure. + */ + page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, + order, zonelist, high_zoneidx, + ALLOC_WMARK_HIGH|ALLOC_CPUSET, + preferred_zone, migratetype); + if (page) + goto out; + + /* The OOM killer will not help higher order allocs */ + if (order > PAGE_ALLOC_COSTLY_ORDER && !(gfp_mask & __GFP_NOFAIL)) + goto out; + + /* Exhausted what can be done so it's blamo time */ + out_of_memory(zonelist, gfp_mask, order); + +out: + clear_zonelist_oom(zonelist, gfp_mask); + return page; +} + +/* The really slow allocator path where we enter direct reclaim */ +static inline struct page * +__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order, + struct zonelist *zonelist, enum zone_type high_zoneidx, + nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone, + int migratetype, unsigned long *did_some_progress) +{ + struct page *page = NULL; + struct reclaim_state reclaim_state; + struct task_struct *p = current; + + cond_resched(); + + /* We now go into synchronous reclaim */ + cpuset_memory_pressure_bump(); + + /* + * The task's cpuset might have expanded its set of allowable nodes + */ + p->flags |= PF_MEMALLOC; + lockdep_set_current_reclaim_state(gfp_mask); + reclaim_state.reclaimed_slab = 0; + p->reclaim_state = &reclaim_state; + + *did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask); + + p->reclaim_state = NULL; + lockdep_clear_current_reclaim_state(); + p->flags &= ~PF_MEMALLOC; + + cond_resched(); + + if (order != 0) + drain_all_pages(); + + if (likely(*did_some_progress)) + page = get_page_from_freelist(gfp_mask, nodemask, order, + zonelist, high_zoneidx, + alloc_flags, preferred_zone, + migratetype); + return page; +} + /* - * This is the 'heart' of the zoned buddy allocator. + * This is called in the allocator slow-path if the allocation request is of + * sufficient urgency to ignore watermarks and take other desperate measures */ -struct page * -__alloc_pages_internal(gfp_t gfp_mask, unsigned int order, - struct zonelist *zonelist, nodemask_t *nodemask) +static inline struct page * +__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order, + struct zonelist *zonelist, enum zone_type high_zoneidx, + nodemask_t *nodemask, struct zone *preferred_zone, + int migratetype) +{ + struct page *page; + + do { + page = get_page_from_freelist(gfp_mask, nodemask, order, + zonelist, high_zoneidx, ALLOC_NO_WATERMARKS, + preferred_zone, migratetype); + + if (!page && gfp_mask & __GFP_NOFAIL) + congestion_wait(WRITE, HZ/50); + } while (!page && (gfp_mask & __GFP_NOFAIL)); + + return page; +} + +static inline +void wake_all_kswapd(unsigned int order, struct zonelist *zonelist, + enum zone_type high_zoneidx) { - const gfp_t wait = gfp_mask & __GFP_WAIT; - enum zone_type high_zoneidx = gfp_zone(gfp_mask); struct zoneref *z; struct zone *zone; - struct page *page; - struct reclaim_state reclaim_state; - struct task_struct *p = current; - int do_retry; - int alloc_flags; - unsigned long did_some_progress; - unsigned long pages_reclaimed = 0; - lockdep_trace_alloc(gfp_mask); + for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) + wakeup_kswapd(zone, order); +} - might_sleep_if(wait); +static inline int +gfp_to_alloc_flags(gfp_t gfp_mask) +{ + struct task_struct *p = current; + int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET; + const gfp_t wait = gfp_mask & __GFP_WAIT; - if (should_fail_alloc_page(gfp_mask, order)) - return NULL; + /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */ + BUILD_BUG_ON(__GFP_HIGH != ALLOC_HIGH); -restart: - z = zonelist->_zonerefs; /* the list of zones suitable for gfp_mask */ + /* + * The caller may dip into page reserves a bit more if the caller + * cannot run direct reclaim, or if the caller has realtime scheduling + * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will + * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH). + */ + alloc_flags |= (gfp_mask & __GFP_HIGH); - if (unlikely(!z->zone)) { + if (!wait) { + alloc_flags |= ALLOC_HARDER; /* - * Happens if we have an empty zonelist as a result of - * GFP_THISNODE being used on a memoryless node + * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. + * See also cpuset_zone_allowed() comment in kernel/cpuset.c. */ - return NULL; + alloc_flags &= ~ALLOC_CPUSET; + } else if (unlikely(rt_task(p))) + alloc_flags |= ALLOC_HARDER; + + if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) { + if (!in_interrupt() && + ((p->flags & PF_MEMALLOC) || + unlikely(test_thread_flag(TIF_MEMDIE)))) + alloc_flags |= ALLOC_NO_WATERMARKS; } - page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order, - zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET); - if (page) - goto got_pg; + return alloc_flags; +} + +static inline struct page * +__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, + struct zonelist *zonelist, enum zone_type high_zoneidx, + nodemask_t *nodemask, struct zone *preferred_zone, + int migratetype) +{ + const gfp_t wait = gfp_mask & __GFP_WAIT; + struct page *page = NULL; + int alloc_flags; + unsigned long pages_reclaimed = 0; + unsigned long did_some_progress; + struct task_struct *p = current; + + /* + * In the slowpath, we sanity check order to avoid ever trying to + * reclaim >= MAX_ORDER areas which will never succeed. Callers may + * be using allocators in order of preference for an area that is + * too large. + */ + if (WARN_ON_ONCE(order >= MAX_ORDER)) + return NULL; /* * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and @@ -1522,154 +1754,83 @@ restart: if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE) goto nopage; - for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) - wakeup_kswapd(zone, order); + wake_all_kswapd(order, zonelist, high_zoneidx); /* * OK, we're below the kswapd watermark and have kicked background * reclaim. Now things get more complex, so set up alloc_flags according * to how we want to proceed. - * - * The caller may dip into page reserves a bit more if the caller - * cannot run direct reclaim, or if the caller has realtime scheduling - * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will - * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH). */ - alloc_flags = ALLOC_WMARK_MIN; - if ((unlikely(rt_task(p)) && !in_interrupt()) || !wait) - alloc_flags |= ALLOC_HARDER; - if (gfp_mask & __GFP_HIGH) - alloc_flags |= ALLOC_HIGH; - if (wait) - alloc_flags |= ALLOC_CPUSET; + alloc_flags = gfp_to_alloc_flags(gfp_mask); - /* - * Go through the zonelist again. Let __GFP_HIGH and allocations - * coming from realtime tasks go deeper into reserves. - * - * This is the last chance, in general, before the goto nopage. - * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. - * See also cpuset_zone_allowed() comment in kernel/cpuset.c. - */ +restart: + /* This is the last chance, in general, before the goto nopage. */ page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, - high_zoneidx, alloc_flags); + high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS, + preferred_zone, migratetype); if (page) goto got_pg; - /* This allocation should allow future memory freeing. */ - rebalance: - if (((p->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE))) - && !in_interrupt()) { - if (!(gfp_mask & __GFP_NOMEMALLOC)) { -nofail_alloc: - /* go through the zonelist yet again, ignoring mins */ - page = get_page_from_freelist(gfp_mask, nodemask, order, - zonelist, high_zoneidx, ALLOC_NO_WATERMARKS); - if (page) - goto got_pg; - if (gfp_mask & __GFP_NOFAIL) { - congestion_wait(WRITE, HZ/50); - goto nofail_alloc; - } - } - goto nopage; + /* Allocate without watermarks if the context allows */ + if (alloc_flags & ALLOC_NO_WATERMARKS) { + page = __alloc_pages_high_priority(gfp_mask, order, + zonelist, high_zoneidx, nodemask, + preferred_zone, migratetype); + if (page) + goto got_pg; } /* Atomic allocations - we can't balance anything */ if (!wait) goto nopage; - cond_resched(); + /* Avoid recursion of direct reclaim */ + if (p->flags & PF_MEMALLOC) + goto nopage; + + /* Try direct reclaim and then allocating */ + page = __alloc_pages_direct_reclaim(gfp_mask, order, + zonelist, high_zoneidx, + nodemask, + alloc_flags, preferred_zone, + migratetype, &did_some_progress); + if (page) + goto got_pg; - /* We now go into synchronous reclaim */ - cpuset_memory_pressure_bump(); /* - * The task's cpuset might have expanded its set of allowable nodes + * If we failed to make any progress reclaiming, then we are + * running out of options and have to consider going OOM */ - cpuset_update_task_memory_state(); - p->flags |= PF_MEMALLOC; - - lockdep_set_current_reclaim_state(gfp_mask); - reclaim_state.reclaimed_slab = 0; - p->reclaim_state = &reclaim_state; - - did_some_progress = try_to_free_pages(zonelist, order, - gfp_mask, nodemask); - - p->reclaim_state = NULL; - lockdep_clear_current_reclaim_state(); - p->flags &= ~PF_MEMALLOC; - - cond_resched(); + if (!did_some_progress) { + if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { + if (oom_killer_disabled) + goto nopage; + page = __alloc_pages_may_oom(gfp_mask, order, + zonelist, high_zoneidx, + nodemask, preferred_zone, + migratetype); + if (page) + goto got_pg; - if (order != 0) - drain_all_pages(); + /* + * The OOM killer does not trigger for high-order + * ~__GFP_NOFAIL allocations so if no progress is being + * made, there are no other options and retrying is + * unlikely to help. + */ + if (order > PAGE_ALLOC_COSTLY_ORDER && + !(gfp_mask & __GFP_NOFAIL)) + goto nopage; - if (likely(did_some_progress)) { - page = get_page_from_freelist(gfp_mask, nodemask, order, - zonelist, high_zoneidx, alloc_flags); - if (page) - goto got_pg; - } else if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { - if (!try_set_zone_oom(zonelist, gfp_mask)) { - schedule_timeout_uninterruptible(1); goto restart; } - - /* - * Go through the zonelist yet one more time, keep - * very high watermark here, this is only to catch - * a parallel oom killing, we must fail if we're still - * under heavy pressure. - */ - page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, - order, zonelist, high_zoneidx, - ALLOC_WMARK_HIGH|ALLOC_CPUSET); - if (page) { - clear_zonelist_oom(zonelist, gfp_mask); - goto got_pg; - } - - /* The OOM killer will not help higher order allocs so fail */ - if (order > PAGE_ALLOC_COSTLY_ORDER) { - clear_zonelist_oom(zonelist, gfp_mask); - goto nopage; - } - - out_of_memory(zonelist, gfp_mask, order); - clear_zonelist_oom(zonelist, gfp_mask); - goto restart; } - /* - * Don't let big-order allocations loop unless the caller explicitly - * requests that. Wait for some write requests to complete then retry. - * - * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER - * means __GFP_NOFAIL, but that may not be true in other - * implementations. - * - * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is - * specified, then we retry until we no longer reclaim any pages - * (above), or we've reclaimed an order of pages at least as - * large as the allocation's order. In both cases, if the - * allocation still fails, we stop retrying. - */ + /* Check if we should retry the allocation */ pages_reclaimed += did_some_progress; - do_retry = 0; - if (!(gfp_mask & __GFP_NORETRY)) { - if (order <= PAGE_ALLOC_COSTLY_ORDER) { - do_retry = 1; - } else { - if (gfp_mask & __GFP_REPEAT && - pages_reclaimed < (1 << order)) - do_retry = 1; - } - if (gfp_mask & __GFP_NOFAIL) - do_retry = 1; - } - if (do_retry) { + if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) { + /* Wait for some write requests to complete then retry */ congestion_wait(WRITE, HZ/50); goto rebalance; } @@ -1687,8 +1848,53 @@ got_pg: if (kmemcheck_enabled) kmemcheck_pagealloc_alloc(page, order, gfp_mask); return page; + +} + +/* + * This is the 'heart' of the zoned buddy allocator. + */ +struct page * +__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, + struct zonelist *zonelist, nodemask_t *nodemask) +{ + enum zone_type high_zoneidx = gfp_zone(gfp_mask); + struct zone *preferred_zone; + struct page *page; + int migratetype = allocflags_to_migratetype(gfp_mask); + + lockdep_trace_alloc(gfp_mask); + + might_sleep_if(gfp_mask & __GFP_WAIT); + + if (should_fail_alloc_page(gfp_mask, order)) + return NULL; + + /* + * Check the zones suitable for the gfp_mask contain at least one + * valid zone. It's possible to have an empty zonelist as a result + * of GFP_THISNODE and a memoryless node + */ + if (unlikely(!zonelist->_zonerefs->zone)) + return NULL; + + /* The preferred zone is used for statistics later */ + first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone); + if (!preferred_zone) + return NULL; + + /* First allocation attempt */ + page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order, + zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET, + preferred_zone, migratetype); + if (unlikely(!page)) + page = __alloc_pages_slowpath(gfp_mask, order, + zonelist, high_zoneidx, nodemask, + preferred_zone, migratetype); + + return page; } -EXPORT_SYMBOL(__alloc_pages_internal); +EXPORT_SYMBOL(__alloc_pages_nodemask); /* * Common helper functions. @@ -1817,7 +2023,7 @@ static unsigned int nr_free_zone_pages(int offset) for_each_zone_zonelist(zone, z, zonelist, offset) { unsigned long size = zone->present_pages; - unsigned long high = zone->pages_high; + unsigned long high = high_wmark_pages(zone); if (size > high) sum += size - high; } @@ -1909,19 +2115,14 @@ void show_free_areas(void) printk("Active_anon:%lu active_file:%lu inactive_anon:%lu\n" " inactive_file:%lu" -//TODO: check/adjust line lengths -#ifdef CONFIG_UNEVICTABLE_LRU " unevictable:%lu" -#endif " dirty:%lu writeback:%lu unstable:%lu\n" " free:%lu slab:%lu mapped:%lu pagetables:%lu bounce:%lu\n", global_page_state(NR_ACTIVE_ANON), global_page_state(NR_ACTIVE_FILE), global_page_state(NR_INACTIVE_ANON), global_page_state(NR_INACTIVE_FILE), -#ifdef CONFIG_UNEVICTABLE_LRU global_page_state(NR_UNEVICTABLE), -#endif global_page_state(NR_FILE_DIRTY), global_page_state(NR_WRITEBACK), global_page_state(NR_UNSTABLE_NFS), @@ -1945,25 +2146,21 @@ void show_free_areas(void) " inactive_anon:%lukB" " active_file:%lukB" " inactive_file:%lukB" -#ifdef CONFIG_UNEVICTABLE_LRU " unevictable:%lukB" -#endif " present:%lukB" " pages_scanned:%lu" " all_unreclaimable? %s" "\n", zone->name, K(zone_page_state(zone, NR_FREE_PAGES)), - K(zone->pages_min), - K(zone->pages_low), - K(zone->pages_high), + K(min_wmark_pages(zone)), + K(low_wmark_pages(zone)), + K(high_wmark_pages(zone)), K(zone_page_state(zone, NR_ACTIVE_ANON)), K(zone_page_state(zone, NR_INACTIVE_ANON)), K(zone_page_state(zone, NR_ACTIVE_FILE)), K(zone_page_state(zone, NR_INACTIVE_FILE)), -#ifdef CONFIG_UNEVICTABLE_LRU K(zone_page_state(zone, NR_UNEVICTABLE)), -#endif K(zone->present_pages), zone->pages_scanned, (zone_is_all_unreclaimable(zone) ? "yes" : "no") @@ -2121,7 +2318,7 @@ int numa_zonelist_order_handler(ctl_table *table, int write, } -#define MAX_NODE_LOAD (num_online_nodes()) +#define MAX_NODE_LOAD (nr_online_nodes) static int node_load[MAX_NUMNODES]; /** @@ -2330,7 +2527,7 @@ static void build_zonelists(pg_data_t *pgdat) /* NUMA-aware ordering of nodes */ local_node = pgdat->node_id; - load = num_online_nodes(); + load = nr_online_nodes; prev_node = local_node; nodes_clear(used_mask); @@ -2481,7 +2678,7 @@ void build_all_zonelists(void) printk("Built %i zonelists in %s order, mobility grouping %s. " "Total pages: %ld\n", - num_online_nodes(), + nr_online_nodes, zonelist_order_name[current_zonelist_order], page_group_by_mobility_disabled ? "off" : "on", vm_total_pages); @@ -2560,8 +2757,8 @@ static inline unsigned long wait_table_bits(unsigned long size) /* * Mark a number of pageblocks as MIGRATE_RESERVE. The number - * of blocks reserved is based on zone->pages_min. The memory within the - * reserve will tend to store contiguous free pages. Setting min_free_kbytes + * of blocks reserved is based on min_wmark_pages(zone). The memory within + * the reserve will tend to store contiguous free pages. Setting min_free_kbytes * higher will lead to a bigger reserve which will get freed as contiguous * blocks as reclaim kicks in */ @@ -2574,7 +2771,7 @@ static void setup_zone_migrate_reserve(struct zone *zone) /* Get the start pfn, end pfn and the number of blocks to reserve */ start_pfn = zone->zone_start_pfn; end_pfn = start_pfn + zone->spanned_pages; - reserve = roundup(zone->pages_min, pageblock_nr_pages) >> + reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >> pageblock_order; for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) { @@ -3506,7 +3703,7 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat, zone_pcp_init(zone); for_each_lru(l) { INIT_LIST_HEAD(&zone->lru[l].list); - zone->lru[l].nr_scan = 0; + zone->lru[l].nr_saved_scan = 0; } zone->reclaim_stat.recent_rotated[0] = 0; zone->reclaim_stat.recent_rotated[1] = 0; @@ -4043,6 +4240,11 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn) early_node_map[i].start_pfn, early_node_map[i].end_pfn); + /* + * find_zone_movable_pfns_for_nodes/early_calculate_totalpages init + * that node_mask, clear it at first + */ + nodes_clear(node_states[N_HIGH_MEMORY]); /* Initialise every node */ mminit_verify_pageflags_layout(); setup_nr_node_ids(); @@ -4177,8 +4379,8 @@ static void calculate_totalreserve_pages(void) max = zone->lowmem_reserve[j]; } - /* we treat pages_high as reserved pages. */ - max += zone->pages_high; + /* we treat the high watermark as reserved pages. */ + max += high_wmark_pages(zone); if (max > zone->present_pages) max = zone->present_pages; @@ -4228,12 +4430,13 @@ static void setup_per_zone_lowmem_reserve(void) } /** - * setup_per_zone_pages_min - called when min_free_kbytes changes. + * setup_per_zone_wmarks - called when min_free_kbytes changes + * or when memory is hot-{added|removed} * - * Ensures that the pages_{min,low,high} values for each zone are set correctly - * with respect to min_free_kbytes. + * Ensures that the watermark[min,low,high] values for each zone are set + * correctly with respect to min_free_kbytes. */ -void setup_per_zone_pages_min(void) +void setup_per_zone_wmarks(void) { unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10); unsigned long lowmem_pages = 0; @@ -4258,7 +4461,7 @@ void setup_per_zone_pages_min(void) * need highmem pages, so cap pages_min to a small * value here. * - * The (pages_high-pages_low) and (pages_low-pages_min) + * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN) * deltas controls asynch page reclaim, and so should * not be capped for highmem. */ @@ -4269,17 +4472,17 @@ void setup_per_zone_pages_min(void) min_pages = SWAP_CLUSTER_MAX; if (min_pages > 128) min_pages = 128; - zone->pages_min = min_pages; + zone->watermark[WMARK_MIN] = min_pages; } else { /* * If it's a lowmem zone, reserve a number of pages * proportionate to the zone's size. */ - zone->pages_min = tmp; + zone->watermark[WMARK_MIN] = tmp; } - zone->pages_low = zone->pages_min + (tmp >> 2); - zone->pages_high = zone->pages_min + (tmp >> 1); + zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2); + zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1); setup_zone_migrate_reserve(zone); spin_unlock_irqrestore(&zone->lock, flags); } @@ -4289,8 +4492,6 @@ void setup_per_zone_pages_min(void) } /** - * setup_per_zone_inactive_ratio - called when min_free_kbytes changes. - * * The inactive anon list should be small enough that the VM never has to * do too much work, but large enough that each inactive page has a chance * to be referenced again before it is swapped out. @@ -4311,21 +4512,26 @@ void setup_per_zone_pages_min(void) * 1TB 101 10GB * 10TB 320 32GB */ -static void setup_per_zone_inactive_ratio(void) +void calculate_zone_inactive_ratio(struct zone *zone) { - struct zone *zone; - - for_each_zone(zone) { - unsigned int gb, ratio; + unsigned int gb, ratio; - /* Zone size in gigabytes */ - gb = zone->present_pages >> (30 - PAGE_SHIFT); + /* Zone size in gigabytes */ + gb = zone->present_pages >> (30 - PAGE_SHIFT); + if (gb) ratio = int_sqrt(10 * gb); - if (!ratio) - ratio = 1; + else + ratio = 1; - zone->inactive_ratio = ratio; - } + zone->inactive_ratio = ratio; +} + +static void __init setup_per_zone_inactive_ratio(void) +{ + struct zone *zone; + + for_each_zone(zone) + calculate_zone_inactive_ratio(zone); } /* @@ -4352,7 +4558,7 @@ static void setup_per_zone_inactive_ratio(void) * 8192MB: 11584k * 16384MB: 16384k */ -static int __init init_per_zone_pages_min(void) +static int __init init_per_zone_wmark_min(void) { unsigned long lowmem_kbytes; @@ -4363,12 +4569,12 @@ static int __init init_per_zone_pages_min(void) min_free_kbytes = 128; if (min_free_kbytes > 65536) min_free_kbytes = 65536; - setup_per_zone_pages_min(); + setup_per_zone_wmarks(); setup_per_zone_lowmem_reserve(); setup_per_zone_inactive_ratio(); return 0; } -module_init(init_per_zone_pages_min) +module_init(init_per_zone_wmark_min) /* * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so @@ -4380,7 +4586,7 @@ int min_free_kbytes_sysctl_handler(ctl_table *table, int write, { proc_dointvec(table, write, file, buffer, length, ppos); if (write) - setup_per_zone_pages_min(); + setup_per_zone_wmarks(); return 0; } @@ -4424,7 +4630,7 @@ int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write, * whenever sysctl_lowmem_reserve_ratio changes. * * The reserve ratio obviously has absolutely no relation with the - * pages_min watermarks. The lowmem reserve ratio can only make sense + * minimum watermarks. The lowmem reserve ratio can only make sense * if in function of the boot time zone sizes. */ int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write, @@ -4531,23 +4737,13 @@ void *__init alloc_large_system_hash(const char *tablename, else if (hashdist) table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL); else { - unsigned long order = get_order(size); - table = (void*) __get_free_pages(GFP_ATOMIC, order); /* * If bucketsize is not a power-of-two, we may free - * some pages at the end of hash table. + * some pages at the end of hash table which + * alloc_pages_exact() automatically does */ - if (table) { - unsigned long alloc_end = (unsigned long)table + - (PAGE_SIZE << order); - unsigned long used = (unsigned long)table + - PAGE_ALIGN(size); - split_page(virt_to_page(table), order); - while (used < alloc_end) { - free_page(used); - used += PAGE_SIZE; - } - } + if (get_order(size) < MAX_ORDER) + table = alloc_pages_exact(size, GFP_ATOMIC); } } while (!table && size > PAGE_SIZE && --log2qty); diff --git a/mm/page_io.c b/mm/page_io.c index 3023c47..c6f3e50 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -120,7 +120,7 @@ out: return ret; } -int swap_readpage(struct file *file, struct page *page) +int swap_readpage(struct page *page) { struct bio *bio; int ret = 0; diff --git a/mm/readahead.c b/mm/readahead.c index 133b6d5..aa1aa23 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -133,15 +133,12 @@ out: } /* - * do_page_cache_readahead actually reads a chunk of disk. It allocates all + * __do_page_cache_readahead() actually reads a chunk of disk. It allocates all * the pages first, then submits them all for I/O. This avoids the very bad * behaviour which would occur if page allocations are causing VM writeback. * We really don't want to intermingle reads and writes like that. * * Returns the number of pages requested, or the maximum amount of I/O allowed. - * - * do_page_cache_readahead() returns -1 if it encountered request queue - * congestion. */ static int __do_page_cache_readahead(struct address_space *mapping, struct file *filp, @@ -210,6 +207,7 @@ int force_page_cache_readahead(struct address_space *mapping, struct file *filp, if (unlikely(!mapping->a_ops->readpage && !mapping->a_ops->readpages)) return -EINVAL; + nr_to_read = max_sane_readahead(nr_to_read); while (nr_to_read) { int err; @@ -231,22 +229,6 @@ int force_page_cache_readahead(struct address_space *mapping, struct file *filp, } /* - * This version skips the IO if the queue is read-congested, and will tell the - * block layer to abandon the readahead if request allocation would block. - * - * force_page_cache_readahead() will ignore queue congestion and will block on - * request queues. - */ -int do_page_cache_readahead(struct address_space *mapping, struct file *filp, - pgoff_t offset, unsigned long nr_to_read) -{ - if (bdi_read_congested(mapping->backing_dev_info)) - return -1; - - return __do_page_cache_readahead(mapping, filp, offset, nr_to_read, 0); -} - -/* * Given a desired number of PAGE_CACHE_SIZE readahead pages, return a * sensible upper limit. */ @@ -259,7 +241,7 @@ unsigned long max_sane_readahead(unsigned long nr) /* * Submit IO for the read-ahead request in file_ra_state. */ -static unsigned long ra_submit(struct file_ra_state *ra, +unsigned long ra_submit(struct file_ra_state *ra, struct address_space *mapping, struct file *filp) { int actual; @@ -348,6 +330,59 @@ static unsigned long get_next_ra_size(struct file_ra_state *ra, */ /* + * Count contiguously cached pages from @offset-1 to @offset-@max, + * this count is a conservative estimation of + * - length of the sequential read sequence, or + * - thrashing threshold in memory tight systems + */ +static pgoff_t count_history_pages(struct address_space *mapping, + struct file_ra_state *ra, + pgoff_t offset, unsigned long max) +{ + pgoff_t head; + + rcu_read_lock(); + head = radix_tree_prev_hole(&mapping->page_tree, offset - 1, max); + rcu_read_unlock(); + + return offset - 1 - head; +} + +/* + * page cache context based read-ahead + */ +static int try_context_readahead(struct address_space *mapping, + struct file_ra_state *ra, + pgoff_t offset, + unsigned long req_size, + unsigned long max) +{ + pgoff_t size; + + size = count_history_pages(mapping, ra, offset, max); + + /* + * no history pages: + * it could be a random read + */ + if (!size) + return 0; + + /* + * starts from beginning of file: + * it is a strong indication of long-run stream (or whole-file-read) + */ + if (size >= offset) + size *= 2; + + ra->start = offset; + ra->size = get_init_ra_size(size + req_size, max); + ra->async_size = ra->size; + + return 1; +} + +/* * A minimal readahead algorithm for trivial sequential/random reads. */ static unsigned long @@ -356,34 +391,26 @@ ondemand_readahead(struct address_space *mapping, bool hit_readahead_marker, pgoff_t offset, unsigned long req_size) { - int max = ra->ra_pages; /* max readahead pages */ - pgoff_t prev_offset; - int sequential; + unsigned long max = max_sane_readahead(ra->ra_pages); + + /* + * start of file + */ + if (!offset) + goto initial_readahead; /* * It's the expected callback offset, assume sequential access. * Ramp up sizes, and push forward the readahead window. */ - if (offset && (offset == (ra->start + ra->size - ra->async_size) || - offset == (ra->start + ra->size))) { + if ((offset == (ra->start + ra->size - ra->async_size) || + offset == (ra->start + ra->size))) { ra->start += ra->size; ra->size = get_next_ra_size(ra, max); ra->async_size = ra->size; goto readit; } - prev_offset = ra->prev_pos >> PAGE_CACHE_SHIFT; - sequential = offset - prev_offset <= 1UL || req_size > max; - - /* - * Standalone, small read. - * Read as is, and do not pollute the readahead state. - */ - if (!hit_readahead_marker && !sequential) { - return __do_page_cache_readahead(mapping, filp, - offset, req_size, 0); - } - /* * Hit a marked page without valid readahead state. * E.g. interleaved reads. @@ -394,7 +421,7 @@ ondemand_readahead(struct address_space *mapping, pgoff_t start; rcu_read_lock(); - start = radix_tree_next_hole(&mapping->page_tree, offset,max+1); + start = radix_tree_next_hole(&mapping->page_tree, offset+1,max); rcu_read_unlock(); if (!start || start - offset > max) @@ -402,23 +429,53 @@ ondemand_readahead(struct address_space *mapping, ra->start = start; ra->size = start - offset; /* old async_size */ + ra->size += req_size; ra->size = get_next_ra_size(ra, max); ra->async_size = ra->size; goto readit; } /* - * It may be one of - * - first read on start of file - * - sequential cache miss - * - oversize random read - * Start readahead for it. + * oversize read + */ + if (req_size > max) + goto initial_readahead; + + /* + * sequential cache miss + */ + if (offset - (ra->prev_pos >> PAGE_CACHE_SHIFT) <= 1UL) + goto initial_readahead; + + /* + * Query the page cache and look for the traces(cached history pages) + * that a sequential stream would leave behind. + */ + if (try_context_readahead(mapping, ra, offset, req_size, max)) + goto readit; + + /* + * standalone, small random read + * Read as is, and do not pollute the readahead state. */ + return __do_page_cache_readahead(mapping, filp, offset, req_size, 0); + +initial_readahead: ra->start = offset; ra->size = get_init_ra_size(req_size, max); ra->async_size = ra->size > req_size ? ra->size - req_size : ra->size; readit: + /* + * Will this read hit the readahead marker made by itself? + * If so, trigger the readahead marker hit now, and merge + * the resulted next readahead window into the current one. + */ + if (offset == ra->start && ra->size == ra->async_size) { + ra->async_size = get_next_ra_size(ra, max); + ra->size += ra->async_size; + } + return ra_submit(ra, mapping, filp); } @@ -333,7 +333,9 @@ static int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma) * repeatedly from either page_referenced_anon or page_referenced_file. */ static int page_referenced_one(struct page *page, - struct vm_area_struct *vma, unsigned int *mapcount) + struct vm_area_struct *vma, + unsigned int *mapcount, + unsigned long *vm_flags) { struct mm_struct *mm = vma->vm_mm; unsigned long address; @@ -381,11 +383,14 @@ out_unmap: (*mapcount)--; pte_unmap_unlock(pte, ptl); out: + if (referenced) + *vm_flags |= vma->vm_flags; return referenced; } static int page_referenced_anon(struct page *page, - struct mem_cgroup *mem_cont) + struct mem_cgroup *mem_cont, + unsigned long *vm_flags) { unsigned int mapcount; struct anon_vma *anon_vma; @@ -405,7 +410,8 @@ static int page_referenced_anon(struct page *page, */ if (mem_cont && !mm_match_cgroup(vma->vm_mm, mem_cont)) continue; - referenced += page_referenced_one(page, vma, &mapcount); + referenced += page_referenced_one(page, vma, + &mapcount, vm_flags); if (!mapcount) break; } @@ -418,6 +424,7 @@ static int page_referenced_anon(struct page *page, * page_referenced_file - referenced check for object-based rmap * @page: the page we're checking references on. * @mem_cont: target memory controller + * @vm_flags: collect encountered vma->vm_flags who actually referenced the page * * For an object-based mapped page, find all the places it is mapped and * check/clear the referenced flag. This is done by following the page->mapping @@ -427,7 +434,8 @@ static int page_referenced_anon(struct page *page, * This function is only called from page_referenced for object-based pages. */ static int page_referenced_file(struct page *page, - struct mem_cgroup *mem_cont) + struct mem_cgroup *mem_cont, + unsigned long *vm_flags) { unsigned int mapcount; struct address_space *mapping = page->mapping; @@ -467,7 +475,8 @@ static int page_referenced_file(struct page *page, */ if (mem_cont && !mm_match_cgroup(vma->vm_mm, mem_cont)) continue; - referenced += page_referenced_one(page, vma, &mapcount); + referenced += page_referenced_one(page, vma, + &mapcount, vm_flags); if (!mapcount) break; } @@ -481,29 +490,35 @@ static int page_referenced_file(struct page *page, * @page: the page to test * @is_locked: caller holds lock on the page * @mem_cont: target memory controller + * @vm_flags: collect encountered vma->vm_flags who actually referenced the page * * Quick test_and_clear_referenced for all mappings to a page, * returns the number of ptes which referenced the page. */ -int page_referenced(struct page *page, int is_locked, - struct mem_cgroup *mem_cont) +int page_referenced(struct page *page, + int is_locked, + struct mem_cgroup *mem_cont, + unsigned long *vm_flags) { int referenced = 0; if (TestClearPageReferenced(page)) referenced++; + *vm_flags = 0; if (page_mapped(page) && page->mapping) { if (PageAnon(page)) - referenced += page_referenced_anon(page, mem_cont); + referenced += page_referenced_anon(page, mem_cont, + vm_flags); else if (is_locked) - referenced += page_referenced_file(page, mem_cont); + referenced += page_referenced_file(page, mem_cont, + vm_flags); else if (!trylock_page(page)) referenced++; else { if (page->mapping) - referenced += - page_referenced_file(page, mem_cont); + referenced += page_referenced_file(page, + mem_cont, vm_flags); unlock_page(page); } } @@ -1202,7 +1217,6 @@ int try_to_unmap(struct page *page, int migration) return ret; } -#ifdef CONFIG_UNEVICTABLE_LRU /** * try_to_munlock - try to munlock a page * @page: the page to be munlocked @@ -1226,4 +1240,4 @@ int try_to_munlock(struct page *page) else return try_to_unmap_file(page, 1, 0); } -#endif + @@ -1097,7 +1097,7 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) shmem_swp_unmap(entry); unlock: spin_unlock(&info->lock); - swap_free(swap); + swapcache_free(swap, NULL); redirty: set_page_dirty(page); if (wbc->for_reclaim) @@ -2612,7 +2612,7 @@ int shmem_unuse(swp_entry_t entry, struct page *page) * @size: size to be set for the file * @flags: VM_NORESERVE suppresses pre-accounting of the entire object size */ -struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags) +struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags) { int error; struct file *file; @@ -818,7 +818,6 @@ static void __slab_error(const char *function, struct kmem_cache *cachep, */ static int use_alien_caches __read_mostly = 1; -static int numa_platform __read_mostly = 1; static int __init noaliencache_setup(char *s) { use_alien_caches = 0; @@ -1377,10 +1376,8 @@ void __init kmem_cache_init(void) int order; int node; - if (num_possible_nodes() == 1) { + if (num_possible_nodes() == 1) use_alien_caches = 0; - numa_platform = 0; - } for (i = 0; i < NUM_INIT_LISTS; i++) { kmem_list3_init(&initkmem_list3[i]); @@ -1627,7 +1624,7 @@ static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid) if (cachep->flags & SLAB_RECLAIM_ACCOUNT) flags |= __GFP_RECLAIMABLE; - page = alloc_pages_node(nodeid, flags | __GFP_NOTRACK, cachep->gfporder); + page = alloc_pages_exact_node(nodeid, flags | __GFP_NOTRACK, cachep->gfporder); if (!page) return NULL; @@ -3193,7 +3190,7 @@ retry: if (local_flags & __GFP_WAIT) local_irq_enable(); kmem_flagcheck(cache, flags); - obj = kmem_getpages(cache, local_flags, -1); + obj = kmem_getpages(cache, local_flags, numa_node_id()); if (local_flags & __GFP_WAIT) local_irq_disable(); if (obj) { @@ -3530,7 +3527,7 @@ static inline void __cache_free(struct kmem_cache *cachep, void *objp) * variable to skip the call, which is mostly likely to be present in * the cache. */ - if (numa_platform && cache_free_alien(cachep, objp)) + if (nr_online_nodes > 1 && cache_free_alien(cachep, objp)) return; if (likely(ac->avail < ac->limit)) { @@ -46,7 +46,7 @@ * NUMA support in SLOB is fairly simplistic, pushing most of the real * logic down to the page allocator, and simply doing the node accounting * on the upper levels. In the event that a node id is explicitly - * provided, alloc_pages_node() with the specified node id is used + * provided, alloc_pages_exact_node() with the specified node id is used * instead. The common case (or when the node id isn't explicitly provided) * will default to the current node, as per numa_node_id(). * @@ -244,7 +244,7 @@ static void *slob_new_pages(gfp_t gfp, int order, int node) #ifdef CONFIG_NUMA if (node != -1) - page = alloc_pages_node(node, gfp, order); + page = alloc_pages_exact_node(node, gfp, order); else #endif page = alloc_pages(gfp, order); @@ -3765,7 +3765,7 @@ static int list_locations(struct kmem_cache *s, char *buf, to_cpumask(l->cpus)); } - if (num_online_nodes() > 1 && !nodes_empty(l->nodes) && + if (nr_online_nodes > 1 && !nodes_empty(l->nodes) && len < PAGE_SIZE - 60) { len += sprintf(buf + len, " nodes="); len += nodelist_scnprintf(buf + len, PAGE_SIZE - len - 50, diff --git a/mm/swap_state.c b/mm/swap_state.c index 1416e7e..42cd38e 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -124,7 +124,6 @@ void __delete_from_swap_cache(struct page *page) /** * add_to_swap - allocate swap space for a page * @page: page we want to move to swap - * @gfp_mask: memory allocation flags * * Allocate swap space for the page and add the page to the * swap cache. Caller needs to hold the page lock. @@ -162,11 +161,11 @@ int add_to_swap(struct page *page) return 1; case -EEXIST: /* Raced with "speculative" read_swap_cache_async */ - swap_free(entry); + swapcache_free(entry, NULL); continue; default: /* -ENOMEM radix-tree allocation failure */ - swap_free(entry); + swapcache_free(entry, NULL); return 0; } } @@ -188,8 +187,7 @@ void delete_from_swap_cache(struct page *page) __delete_from_swap_cache(page); spin_unlock_irq(&swapper_space.tree_lock); - mem_cgroup_uncharge_swapcache(page, entry); - swap_free(entry); + swapcache_free(entry, page); page_cache_release(page); } @@ -293,7 +291,10 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, /* * Swap entry may have been freed since our caller observed it. */ - if (!swap_duplicate(entry)) + err = swapcache_prepare(entry); + if (err == -EEXIST) /* seems racy */ + continue; + if (err) /* swp entry is obsolete ? */ break; /* @@ -312,12 +313,12 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, * Initiate read into locked page and return. */ lru_cache_add_anon(new_page); - swap_readpage(NULL, new_page); + swap_readpage(new_page); return new_page; } ClearPageSwapBacked(new_page); __clear_page_locked(new_page); - swap_free(entry); + swapcache_free(entry, NULL); } while (err != -ENOMEM); if (new_page) diff --git a/mm/swapfile.c b/mm/swapfile.c index 312fafe..28faa01 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -53,6 +53,59 @@ static struct swap_info_struct swap_info[MAX_SWAPFILES]; static DEFINE_MUTEX(swapon_mutex); +/* For reference count accounting in swap_map */ +/* enum for swap_map[] handling. internal use only */ +enum { + SWAP_MAP = 0, /* ops for reference from swap users */ + SWAP_CACHE, /* ops for reference from swap cache */ +}; + +static inline int swap_count(unsigned short ent) +{ + return ent & SWAP_COUNT_MASK; +} + +static inline bool swap_has_cache(unsigned short ent) +{ + return !!(ent & SWAP_HAS_CACHE); +} + +static inline unsigned short encode_swapmap(int count, bool has_cache) +{ + unsigned short ret = count; + + if (has_cache) + return SWAP_HAS_CACHE | ret; + return ret; +} + +/* returnes 1 if swap entry is freed */ +static int +__try_to_reclaim_swap(struct swap_info_struct *si, unsigned long offset) +{ + int type = si - swap_info; + swp_entry_t entry = swp_entry(type, offset); + struct page *page; + int ret = 0; + + page = find_get_page(&swapper_space, entry.val); + if (!page) + return 0; + /* + * This function is called from scan_swap_map() and it's called + * by vmscan.c at reclaiming pages. So, we hold a lock on a page, here. + * We have to use trylock for avoiding deadlock. This is a special + * case and you should use try_to_free_swap() with explicit lock_page() + * in usual operations. + */ + if (trylock_page(page)) { + ret = try_to_free_swap(page); + unlock_page(page); + } + page_cache_release(page); + return ret; +} + /* * We need this because the bdev->unplug_fn can sleep and we cannot * hold swap_lock while calling the unplug_fn. And swap_lock @@ -167,7 +220,8 @@ static int wait_for_discard(void *word) #define SWAPFILE_CLUSTER 256 #define LATENCY_LIMIT 256 -static inline unsigned long scan_swap_map(struct swap_info_struct *si) +static inline unsigned long scan_swap_map(struct swap_info_struct *si, + int cache) { unsigned long offset; unsigned long scan_base; @@ -273,6 +327,19 @@ checks: goto no_page; if (offset > si->highest_bit) scan_base = offset = si->lowest_bit; + + /* reuse swap entry of cache-only swap if not busy. */ + if (vm_swap_full() && si->swap_map[offset] == SWAP_HAS_CACHE) { + int swap_was_freed; + spin_unlock(&swap_lock); + swap_was_freed = __try_to_reclaim_swap(si, offset); + spin_lock(&swap_lock); + /* entry was freed successfully, try to use this again */ + if (swap_was_freed) + goto checks; + goto scan; /* check next one */ + } + if (si->swap_map[offset]) goto scan; @@ -285,7 +352,10 @@ checks: si->lowest_bit = si->max; si->highest_bit = 0; } - si->swap_map[offset] = 1; + if (cache == SWAP_CACHE) /* at usual swap-out via vmscan.c */ + si->swap_map[offset] = encode_swapmap(0, true); + else /* at suspend */ + si->swap_map[offset] = encode_swapmap(1, false); si->cluster_next = offset + 1; si->flags -= SWP_SCANNING; @@ -351,6 +421,10 @@ scan: spin_lock(&swap_lock); goto checks; } + if (vm_swap_full() && si->swap_map[offset] == SWAP_HAS_CACHE) { + spin_lock(&swap_lock); + goto checks; + } if (unlikely(--latency_ration < 0)) { cond_resched(); latency_ration = LATENCY_LIMIT; @@ -362,6 +436,10 @@ scan: spin_lock(&swap_lock); goto checks; } + if (vm_swap_full() && si->swap_map[offset] == SWAP_HAS_CACHE) { + spin_lock(&swap_lock); + goto checks; + } if (unlikely(--latency_ration < 0)) { cond_resched(); latency_ration = LATENCY_LIMIT; @@ -401,7 +479,8 @@ swp_entry_t get_swap_page(void) continue; swap_list.next = next; - offset = scan_swap_map(si); + /* This is called for allocating swap entry for cache */ + offset = scan_swap_map(si, SWAP_CACHE); if (offset) { spin_unlock(&swap_lock); return swp_entry(type, offset); @@ -415,6 +494,7 @@ noswap: return (swp_entry_t) {0}; } +/* The only caller of this function is now susupend routine */ swp_entry_t get_swap_page_of_type(int type) { struct swap_info_struct *si; @@ -424,7 +504,8 @@ swp_entry_t get_swap_page_of_type(int type) si = swap_info + type; if (si->flags & SWP_WRITEOK) { nr_swap_pages--; - offset = scan_swap_map(si); + /* This is called for allocating swap entry, not cache */ + offset = scan_swap_map(si, SWAP_MAP); if (offset) { spin_unlock(&swap_lock); return swp_entry(type, offset); @@ -471,25 +552,38 @@ out: return NULL; } -static int swap_entry_free(struct swap_info_struct *p, swp_entry_t ent) +static int swap_entry_free(struct swap_info_struct *p, + swp_entry_t ent, int cache) { unsigned long offset = swp_offset(ent); - int count = p->swap_map[offset]; - - if (count < SWAP_MAP_MAX) { - count--; - p->swap_map[offset] = count; - if (!count) { - if (offset < p->lowest_bit) - p->lowest_bit = offset; - if (offset > p->highest_bit) - p->highest_bit = offset; - if (p->prio > swap_info[swap_list.next].prio) - swap_list.next = p - swap_info; - nr_swap_pages++; - p->inuse_pages--; - mem_cgroup_uncharge_swap(ent); + int count = swap_count(p->swap_map[offset]); + bool has_cache; + + has_cache = swap_has_cache(p->swap_map[offset]); + + if (cache == SWAP_MAP) { /* dropping usage count of swap */ + if (count < SWAP_MAP_MAX) { + count--; + p->swap_map[offset] = encode_swapmap(count, has_cache); } + } else { /* dropping swap cache flag */ + VM_BUG_ON(!has_cache); + p->swap_map[offset] = encode_swapmap(count, false); + + } + /* return code. */ + count = p->swap_map[offset]; + /* free if no reference */ + if (!count) { + if (offset < p->lowest_bit) + p->lowest_bit = offset; + if (offset > p->highest_bit) + p->highest_bit = offset; + if (p->prio > swap_info[swap_list.next].prio) + swap_list.next = p - swap_info; + nr_swap_pages++; + p->inuse_pages--; + mem_cgroup_uncharge_swap(ent); } return count; } @@ -504,9 +598,26 @@ void swap_free(swp_entry_t entry) p = swap_info_get(entry); if (p) { - swap_entry_free(p, entry); + swap_entry_free(p, entry, SWAP_MAP); + spin_unlock(&swap_lock); + } +} + +/* + * Called after dropping swapcache to decrease refcnt to swap entries. + */ +void swapcache_free(swp_entry_t entry, struct page *page) +{ + struct swap_info_struct *p; + + if (page) + mem_cgroup_uncharge_swapcache(page, entry); + p = swap_info_get(entry); + if (p) { + swap_entry_free(p, entry, SWAP_CACHE); spin_unlock(&swap_lock); } + return; } /* @@ -521,8 +632,7 @@ static inline int page_swapcount(struct page *page) entry.val = page_private(page); p = swap_info_get(entry); if (p) { - /* Subtract the 1 for the swap cache itself */ - count = p->swap_map[swp_offset(entry)] - 1; + count = swap_count(p->swap_map[swp_offset(entry)]); spin_unlock(&swap_lock); } return count; @@ -584,7 +694,7 @@ int free_swap_and_cache(swp_entry_t entry) p = swap_info_get(entry); if (p) { - if (swap_entry_free(p, entry) == 1) { + if (swap_entry_free(p, entry, SWAP_MAP) == SWAP_HAS_CACHE) { page = find_get_page(&swapper_space, entry.val); if (page && !trylock_page(page)) { page_cache_release(page); @@ -891,7 +1001,7 @@ static unsigned int find_next_to_unuse(struct swap_info_struct *si, i = 1; } count = si->swap_map[i]; - if (count && count != SWAP_MAP_BAD) + if (count && swap_count(count) != SWAP_MAP_BAD) break; } return i; @@ -995,13 +1105,13 @@ static int try_to_unuse(unsigned int type) */ shmem = 0; swcount = *swap_map; - if (swcount > 1) { + if (swap_count(swcount)) { if (start_mm == &init_mm) shmem = shmem_unuse(entry, page); else retval = unuse_mm(start_mm, entry, page); } - if (*swap_map > 1) { + if (swap_count(*swap_map)) { int set_start_mm = (*swap_map >= swcount); struct list_head *p = &start_mm->mmlist; struct mm_struct *new_start_mm = start_mm; @@ -1011,7 +1121,7 @@ static int try_to_unuse(unsigned int type) atomic_inc(&new_start_mm->mm_users); atomic_inc(&prev_mm->mm_users); spin_lock(&mmlist_lock); - while (*swap_map > 1 && !retval && !shmem && + while (swap_count(*swap_map) && !retval && !shmem && (p = p->next) != &start_mm->mmlist) { mm = list_entry(p, struct mm_struct, mmlist); if (!atomic_inc_not_zero(&mm->mm_users)) @@ -1023,14 +1133,16 @@ static int try_to_unuse(unsigned int type) cond_resched(); swcount = *swap_map; - if (swcount <= 1) + if (!swap_count(swcount)) /* any usage ? */ ; else if (mm == &init_mm) { set_start_mm = 1; shmem = shmem_unuse(entry, page); } else retval = unuse_mm(mm, entry, page); - if (set_start_mm && *swap_map < swcount) { + + if (set_start_mm && + swap_count(*swap_map) < swcount) { mmput(new_start_mm); atomic_inc(&mm->mm_users); new_start_mm = mm; @@ -1057,21 +1169,25 @@ static int try_to_unuse(unsigned int type) } /* - * How could swap count reach 0x7fff when the maximum - * pid is 0x7fff, and there's no way to repeat a swap - * page within an mm (except in shmem, where it's the - * shared object which takes the reference count)? - * We believe SWAP_MAP_MAX cannot occur in Linux 2.4. - * + * How could swap count reach 0x7ffe ? + * There's no way to repeat a swap page within an mm + * (except in shmem, where it's the shared object which takes + * the reference count)? + * We believe SWAP_MAP_MAX cannot occur.(if occur, unsigned + * short is too small....) * If that's wrong, then we should worry more about * exit_mmap() and do_munmap() cases described above: * we might be resetting SWAP_MAP_MAX too early here. * We know "Undead"s can happen, they're okay, so don't * report them; but do report if we reset SWAP_MAP_MAX. */ - if (*swap_map == SWAP_MAP_MAX) { + /* We might release the lock_page() in unuse_mm(). */ + if (!PageSwapCache(page) || page_private(page) != entry.val) + goto retry; + + if (swap_count(*swap_map) == SWAP_MAP_MAX) { spin_lock(&swap_lock); - *swap_map = 1; + *swap_map = encode_swapmap(0, true); spin_unlock(&swap_lock); reset_overflow = 1; } @@ -1089,7 +1205,8 @@ static int try_to_unuse(unsigned int type) * pages would be incorrect if swap supported "shared * private" pages, but they are handled by tmpfs files. */ - if ((*swap_map > 1) && PageDirty(page) && PageSwapCache(page)) { + if (swap_count(*swap_map) && + PageDirty(page) && PageSwapCache(page)) { struct writeback_control wbc = { .sync_mode = WB_SYNC_NONE, }; @@ -1116,6 +1233,7 @@ static int try_to_unuse(unsigned int type) * mark page dirty so shrink_page_list will preserve it. */ SetPageDirty(page); +retry: unlock_page(page); page_cache_release(page); @@ -1942,15 +2060,23 @@ void si_swapinfo(struct sysinfo *val) * * Note: if swap_map[] reaches SWAP_MAP_MAX the entries are treated as * "permanent", but will be reclaimed by the next swapoff. + * Returns error code in following case. + * - success -> 0 + * - swp_entry is invalid -> EINVAL + * - swp_entry is migration entry -> EINVAL + * - swap-cache reference is requested but there is already one. -> EEXIST + * - swap-cache reference is requested but the entry is not used. -> ENOENT */ -int swap_duplicate(swp_entry_t entry) +static int __swap_duplicate(swp_entry_t entry, bool cache) { struct swap_info_struct * p; unsigned long offset, type; - int result = 0; + int result = -EINVAL; + int count; + bool has_cache; if (is_migration_entry(entry)) - return 1; + return -EINVAL; type = swp_type(entry); if (type >= nr_swapfiles) @@ -1959,17 +2085,40 @@ int swap_duplicate(swp_entry_t entry) offset = swp_offset(entry); spin_lock(&swap_lock); - if (offset < p->max && p->swap_map[offset]) { - if (p->swap_map[offset] < SWAP_MAP_MAX - 1) { - p->swap_map[offset]++; - result = 1; - } else if (p->swap_map[offset] <= SWAP_MAP_MAX) { + + if (unlikely(offset >= p->max)) + goto unlock_out; + + count = swap_count(p->swap_map[offset]); + has_cache = swap_has_cache(p->swap_map[offset]); + + if (cache == SWAP_CACHE) { /* called for swapcache/swapin-readahead */ + + /* set SWAP_HAS_CACHE if there is no cache and entry is used */ + if (!has_cache && count) { + p->swap_map[offset] = encode_swapmap(count, true); + result = 0; + } else if (has_cache) /* someone added cache */ + result = -EEXIST; + else if (!count) /* no users */ + result = -ENOENT; + + } else if (count || has_cache) { + if (count < SWAP_MAP_MAX - 1) { + p->swap_map[offset] = encode_swapmap(count + 1, + has_cache); + result = 0; + } else if (count <= SWAP_MAP_MAX) { if (swap_overflow++ < 5) - printk(KERN_WARNING "swap_dup: swap entry overflow\n"); - p->swap_map[offset] = SWAP_MAP_MAX; - result = 1; + printk(KERN_WARNING + "swap_dup: swap entry overflow\n"); + p->swap_map[offset] = encode_swapmap(SWAP_MAP_MAX, + has_cache); + result = 0; } - } + } else + result = -ENOENT; /* unused swap entry */ +unlock_out: spin_unlock(&swap_lock); out: return result; @@ -1978,6 +2127,27 @@ bad_file: printk(KERN_ERR "swap_dup: %s%08lx\n", Bad_file, entry.val); goto out; } +/* + * increase reference count of swap entry by 1. + */ +void swap_duplicate(swp_entry_t entry) +{ + __swap_duplicate(entry, SWAP_MAP); +} + +/* + * @entry: swap entry for which we allocate swap cache. + * + * Called when allocating swap cache for exising swap entry, + * This can return error codes. Returns 0 at success. + * -EBUSY means there is a swap cache. + * Note: return code is different from swap_duplicate(). + */ +int swapcache_prepare(swp_entry_t entry) +{ + return __swap_duplicate(entry, SWAP_CACHE); +} + struct swap_info_struct * get_swap_info_struct(unsigned type) @@ -2016,7 +2186,7 @@ int valid_swaphandles(swp_entry_t entry, unsigned long *offset) /* Don't read in free or bad pages */ if (!si->swap_map[toff]) break; - if (si->swap_map[toff] == SWAP_MAP_BAD) + if (swap_count(si->swap_map[toff]) == SWAP_MAP_BAD) break; } /* Count contiguous allocated slots below our target */ @@ -2024,7 +2194,7 @@ int valid_swaphandles(swp_entry_t entry, unsigned long *offset) /* Don't read in free or bad pages */ if (!si->swap_map[toff]) break; - if (si->swap_map[toff] == SWAP_MAP_BAD) + if (swap_count(si->swap_map[toff]) == SWAP_MAP_BAD) break; } spin_unlock(&swap_lock); diff --git a/mm/truncate.c b/mm/truncate.c index 12e1579..ccc3ecf 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -267,8 +267,21 @@ void truncate_inode_pages(struct address_space *mapping, loff_t lstart) } EXPORT_SYMBOL(truncate_inode_pages); -unsigned long __invalidate_mapping_pages(struct address_space *mapping, - pgoff_t start, pgoff_t end, bool be_atomic) +/** + * invalidate_mapping_pages - Invalidate all the unlocked pages of one inode + * @mapping: the address_space which holds the pages to invalidate + * @start: the offset 'from' which to invalidate + * @end: the offset 'to' which to invalidate (inclusive) + * + * This function only removes the unlocked pages, if you want to + * remove all the pages of one inode, you must call truncate_inode_pages. + * + * invalidate_mapping_pages() will not block on IO activity. It will not + * invalidate pages which are dirty, locked, under writeback or mapped into + * pagetables. + */ +unsigned long invalidate_mapping_pages(struct address_space *mapping, + pgoff_t start, pgoff_t end) { struct pagevec pvec; pgoff_t next = start; @@ -309,30 +322,10 @@ unlock: break; } pagevec_release(&pvec); - if (likely(!be_atomic)) - cond_resched(); + cond_resched(); } return ret; } - -/** - * invalidate_mapping_pages - Invalidate all the unlocked pages of one inode - * @mapping: the address_space which holds the pages to invalidate - * @start: the offset 'from' which to invalidate - * @end: the offset 'to' which to invalidate (inclusive) - * - * This function only removes the unlocked pages, if you want to - * remove all the pages of one inode, you must call truncate_inode_pages. - * - * invalidate_mapping_pages() will not block on IO activity. It will not - * invalidate pages which are dirty, locked, under writeback or mapped into - * pagetables. - */ -unsigned long invalidate_mapping_pages(struct address_space *mapping, - pgoff_t start, pgoff_t end) -{ - return __invalidate_mapping_pages(mapping, start, end, false); -} EXPORT_SYMBOL(invalidate_mapping_pages); /* @@ -233,13 +233,21 @@ void arch_pick_mmap_layout(struct mm_struct *mm) * @pages: array that receives pointers to the pages pinned. * Should be at least nr_pages long. * - * Attempt to pin user pages in memory without taking mm->mmap_sem. - * If not successful, it will fall back to taking the lock and - * calling get_user_pages(). - * * Returns number of pages pinned. This may be fewer than the number * requested. If nr_pages is 0 or negative, returns 0. If no pages * were pinned, returns -errno. + * + * get_user_pages_fast provides equivalent functionality to get_user_pages, + * operating on current and current->mm, with force=0 and vma=NULL. However + * unlike get_user_pages, it must be called without mmap_sem held. + * + * get_user_pages_fast may take mmap_sem and page table locks, so no + * assumptions can be made about lack of locking. get_user_pages_fast is to be + * implemented in a way that is advantageous (vs get_user_pages()) when the + * user memory area is already faulted in and present in ptes. However if the + * pages have to be faulted in, it may turn out to be slightly slower so + * callers need to carefully consider what to use. On many architectures, + * get_user_pages_fast simply falls back to get_user_pages. */ int __attribute__((weak)) get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) diff --git a/mm/vmscan.c b/mm/vmscan.c index 95c08a8..4139aa5 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -470,8 +470,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page) swp_entry_t swap = { .val = page_private(page) }; __delete_from_swap_cache(page); spin_unlock_irq(&mapping->tree_lock); - mem_cgroup_uncharge_swapcache(page, swap); - swap_free(swap); + swapcache_free(swap, page); } else { __remove_from_page_cache(page); spin_unlock_irq(&mapping->tree_lock); @@ -514,7 +513,6 @@ int remove_mapping(struct address_space *mapping, struct page *page) * * lru_lock must not be held, interrupts must be enabled. */ -#ifdef CONFIG_UNEVICTABLE_LRU void putback_lru_page(struct page *page) { int lru; @@ -568,20 +566,6 @@ redo: put_page(page); /* drop ref from isolate */ } -#else /* CONFIG_UNEVICTABLE_LRU */ - -void putback_lru_page(struct page *page) -{ - int lru; - VM_BUG_ON(PageLRU(page)); - - lru = !!TestClearPageActive(page) + page_is_file_cache(page); - lru_cache_add_lru(page, lru); - put_page(page); -} -#endif /* CONFIG_UNEVICTABLE_LRU */ - - /* * shrink_page_list() returns the number of reclaimed pages */ @@ -593,6 +577,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, struct pagevec freed_pvec; int pgactivate = 0; unsigned long nr_reclaimed = 0; + unsigned long vm_flags; cond_resched(); @@ -643,7 +628,8 @@ static unsigned long shrink_page_list(struct list_head *page_list, goto keep_locked; } - referenced = page_referenced(page, 1, sc->mem_cgroup); + referenced = page_referenced(page, 1, + sc->mem_cgroup, &vm_flags); /* In active use or really unfreeable? Activate it. */ if (sc->order <= PAGE_ALLOC_COSTLY_ORDER && referenced && page_mapping_inuse(page)) @@ -943,18 +929,10 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, /* Check that we have not crossed a zone boundary. */ if (unlikely(page_zone_id(cursor_page) != zone_id)) continue; - switch (__isolate_lru_page(cursor_page, mode, file)) { - case 0: + if (__isolate_lru_page(cursor_page, mode, file) == 0) { list_move(&cursor_page->lru, dst); nr_taken++; scan++; - break; - - case -EBUSY: - /* else it is being freed elsewhere */ - list_move(&cursor_page->lru, src); - default: - break; /* ! on LRU or wrong list */ } } } @@ -1061,6 +1039,19 @@ static unsigned long shrink_inactive_list(unsigned long max_scan, unsigned long nr_scanned = 0; unsigned long nr_reclaimed = 0; struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); + int lumpy_reclaim = 0; + + /* + * If we need a large contiguous chunk of memory, or have + * trouble getting a small set of contiguous pages, we + * will reclaim both active and inactive pages. + * + * We use the same threshold as pageout congestion_wait below. + */ + if (sc->order > PAGE_ALLOC_COSTLY_ORDER) + lumpy_reclaim = 1; + else if (sc->order && priority < DEF_PRIORITY - 2) + lumpy_reclaim = 1; pagevec_init(&pvec, 1); @@ -1073,19 +1064,7 @@ static unsigned long shrink_inactive_list(unsigned long max_scan, unsigned long nr_freed; unsigned long nr_active; unsigned int count[NR_LRU_LISTS] = { 0, }; - int mode = ISOLATE_INACTIVE; - - /* - * If we need a large contiguous chunk of memory, or have - * trouble getting a small set of contiguous pages, we - * will reclaim both active and inactive pages. - * - * We use the same threshold as pageout congestion_wait below. - */ - if (sc->order > PAGE_ALLOC_COSTLY_ORDER) - mode = ISOLATE_BOTH; - else if (sc->order && priority < DEF_PRIORITY - 2) - mode = ISOLATE_BOTH; + int mode = lumpy_reclaim ? ISOLATE_BOTH : ISOLATE_INACTIVE; nr_taken = sc->isolate_pages(sc->swap_cluster_max, &page_list, &nr_scan, sc->order, mode, @@ -1122,7 +1101,7 @@ static unsigned long shrink_inactive_list(unsigned long max_scan, * but that should be acceptable to the caller */ if (nr_freed < nr_taken && !current_is_kswapd() && - sc->order > PAGE_ALLOC_COSTLY_ORDER) { + lumpy_reclaim) { congestion_wait(WRITE, HZ/10); /* @@ -1217,18 +1196,54 @@ static inline void note_zone_scanning_priority(struct zone *zone, int priority) * But we had to alter page->flags anyway. */ +static void move_active_pages_to_lru(struct zone *zone, + struct list_head *list, + enum lru_list lru) +{ + unsigned long pgmoved = 0; + struct pagevec pvec; + struct page *page; + + pagevec_init(&pvec, 1); + + while (!list_empty(list)) { + page = lru_to_page(list); + prefetchw_prev_lru_page(page, list, flags); + + VM_BUG_ON(PageLRU(page)); + SetPageLRU(page); + + VM_BUG_ON(!PageActive(page)); + if (!is_active_lru(lru)) + ClearPageActive(page); /* we are de-activating */ + + list_move(&page->lru, &zone->lru[lru].list); + mem_cgroup_add_lru_list(page, lru); + pgmoved++; + + if (!pagevec_add(&pvec, page) || list_empty(list)) { + spin_unlock_irq(&zone->lru_lock); + if (buffer_heads_over_limit) + pagevec_strip(&pvec); + __pagevec_release(&pvec); + spin_lock_irq(&zone->lru_lock); + } + } + __mod_zone_page_state(zone, NR_LRU_BASE + lru, pgmoved); + if (!is_active_lru(lru)) + __count_vm_events(PGDEACTIVATE, pgmoved); +} static void shrink_active_list(unsigned long nr_pages, struct zone *zone, struct scan_control *sc, int priority, int file) { unsigned long pgmoved; - int pgdeactivate = 0; unsigned long pgscanned; + unsigned long vm_flags; LIST_HEAD(l_hold); /* The pages which were snipped off */ + LIST_HEAD(l_active); LIST_HEAD(l_inactive); struct page *page; - struct pagevec pvec; - enum lru_list lru; struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); lru_add_drain(); @@ -1245,13 +1260,14 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, } reclaim_stat->recent_scanned[!!file] += pgmoved; + __count_zone_vm_events(PGREFILL, zone, pgscanned); if (file) __mod_zone_page_state(zone, NR_ACTIVE_FILE, -pgmoved); else __mod_zone_page_state(zone, NR_ACTIVE_ANON, -pgmoved); spin_unlock_irq(&zone->lru_lock); - pgmoved = 0; + pgmoved = 0; /* count referenced (mapping) mapped pages */ while (!list_empty(&l_hold)) { cond_resched(); page = lru_to_page(&l_hold); @@ -1264,58 +1280,44 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, /* page_referenced clears PageReferenced */ if (page_mapping_inuse(page) && - page_referenced(page, 0, sc->mem_cgroup)) + page_referenced(page, 0, sc->mem_cgroup, &vm_flags)) { pgmoved++; + /* + * Identify referenced, file-backed active pages and + * give them one more trip around the active list. So + * that executable code get better chances to stay in + * memory under moderate memory pressure. Anon pages + * are not likely to be evicted by use-once streaming + * IO, plus JVM can create lots of anon VM_EXEC pages, + * so we ignore them here. + */ + if ((vm_flags & VM_EXEC) && !PageAnon(page)) { + list_add(&page->lru, &l_active); + continue; + } + } list_add(&page->lru, &l_inactive); } /* - * Move the pages to the [file or anon] inactive list. + * Move pages back to the lru list. */ - pagevec_init(&pvec, 1); - lru = LRU_BASE + file * LRU_FILE; - spin_lock_irq(&zone->lru_lock); /* - * Count referenced pages from currently used mappings as - * rotated, even though they are moved to the inactive list. - * This helps balance scan pressure between file and anonymous - * pages in get_scan_ratio. + * Count referenced pages from currently used mappings as rotated, + * even though only some of them are actually re-activated. This + * helps balance scan pressure between file and anonymous pages in + * get_scan_ratio. */ reclaim_stat->recent_rotated[!!file] += pgmoved; - pgmoved = 0; - while (!list_empty(&l_inactive)) { - page = lru_to_page(&l_inactive); - prefetchw_prev_lru_page(page, &l_inactive, flags); - VM_BUG_ON(PageLRU(page)); - SetPageLRU(page); - VM_BUG_ON(!PageActive(page)); - ClearPageActive(page); + move_active_pages_to_lru(zone, &l_active, + LRU_ACTIVE + file * LRU_FILE); + move_active_pages_to_lru(zone, &l_inactive, + LRU_BASE + file * LRU_FILE); - list_move(&page->lru, &zone->lru[lru].list); - mem_cgroup_add_lru_list(page, lru); - pgmoved++; - if (!pagevec_add(&pvec, page)) { - __mod_zone_page_state(zone, NR_LRU_BASE + lru, pgmoved); - spin_unlock_irq(&zone->lru_lock); - pgdeactivate += pgmoved; - pgmoved = 0; - if (buffer_heads_over_limit) - pagevec_strip(&pvec); - __pagevec_release(&pvec); - spin_lock_irq(&zone->lru_lock); - } - } - __mod_zone_page_state(zone, NR_LRU_BASE + lru, pgmoved); - pgdeactivate += pgmoved; - __count_zone_vm_events(PGREFILL, zone, pgscanned); - __count_vm_events(PGDEACTIVATE, pgdeactivate); spin_unlock_irq(&zone->lru_lock); - if (buffer_heads_over_limit) - pagevec_strip(&pvec); - pagevec_release(&pvec); } static int inactive_anon_is_low_global(struct zone *zone) @@ -1350,12 +1352,48 @@ static int inactive_anon_is_low(struct zone *zone, struct scan_control *sc) return low; } +static int inactive_file_is_low_global(struct zone *zone) +{ + unsigned long active, inactive; + + active = zone_page_state(zone, NR_ACTIVE_FILE); + inactive = zone_page_state(zone, NR_INACTIVE_FILE); + + return (active > inactive); +} + +/** + * inactive_file_is_low - check if file pages need to be deactivated + * @zone: zone to check + * @sc: scan control of this context + * + * When the system is doing streaming IO, memory pressure here + * ensures that active file pages get deactivated, until more + * than half of the file pages are on the inactive list. + * + * Once we get to that situation, protect the system's working + * set from being evicted by disabling active file page aging. + * + * This uses a different ratio than the anonymous pages, because + * the page cache uses a use-once replacement algorithm. + */ +static int inactive_file_is_low(struct zone *zone, struct scan_control *sc) +{ + int low; + + if (scanning_global_lru(sc)) + low = inactive_file_is_low_global(zone); + else + low = mem_cgroup_inactive_file_is_low(sc->mem_cgroup); + return low; +} + static unsigned long shrink_list(enum lru_list lru, unsigned long nr_to_scan, struct zone *zone, struct scan_control *sc, int priority) { int file = is_file_lru(lru); - if (lru == LRU_ACTIVE_FILE) { + if (lru == LRU_ACTIVE_FILE && inactive_file_is_low(zone, sc)) { shrink_active_list(nr_to_scan, zone, sc, priority, file); return 0; } @@ -1384,13 +1422,6 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc, unsigned long ap, fp; struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); - /* If we have no swap space, do not bother scanning anon pages. */ - if (!sc->may_swap || (nr_swap_pages <= 0)) { - percent[0] = 0; - percent[1] = 100; - return; - } - anon = zone_nr_pages(zone, sc, LRU_ACTIVE_ANON) + zone_nr_pages(zone, sc, LRU_INACTIVE_ANON); file = zone_nr_pages(zone, sc, LRU_ACTIVE_FILE) + @@ -1400,7 +1431,7 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc, free = zone_page_state(zone, NR_FREE_PAGES); /* If we have very few page cache pages, force-scan anon pages. */ - if (unlikely(file + free <= zone->pages_high)) { + if (unlikely(file + free <= high_wmark_pages(zone))) { percent[0] = 100; percent[1] = 0; return; @@ -1455,6 +1486,26 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc, percent[1] = 100 - percent[0]; } +/* + * Smallish @nr_to_scan's are deposited in @nr_saved_scan, + * until we collected @swap_cluster_max pages to scan. + */ +static unsigned long nr_scan_try_batch(unsigned long nr_to_scan, + unsigned long *nr_saved_scan, + unsigned long swap_cluster_max) +{ + unsigned long nr; + + *nr_saved_scan += nr_to_scan; + nr = *nr_saved_scan; + + if (nr >= swap_cluster_max) + *nr_saved_scan = 0; + else + nr = 0; + + return nr; +} /* * This is a basic per-zone page freer. Used by both kswapd and direct reclaim. @@ -1468,26 +1519,30 @@ static void shrink_zone(int priority, struct zone *zone, enum lru_list l; unsigned long nr_reclaimed = sc->nr_reclaimed; unsigned long swap_cluster_max = sc->swap_cluster_max; + int noswap = 0; - get_scan_ratio(zone, sc, percent); + /* If we have no swap space, do not bother scanning anon pages. */ + if (!sc->may_swap || (nr_swap_pages <= 0)) { + noswap = 1; + percent[0] = 0; + percent[1] = 100; + } else + get_scan_ratio(zone, sc, percent); for_each_evictable_lru(l) { int file = is_file_lru(l); unsigned long scan; scan = zone_nr_pages(zone, sc, l); - if (priority) { + if (priority || noswap) { scan >>= priority; scan = (scan * percent[file]) / 100; } - if (scanning_global_lru(sc)) { - zone->lru[l].nr_scan += scan; - nr[l] = zone->lru[l].nr_scan; - if (nr[l] >= swap_cluster_max) - zone->lru[l].nr_scan = 0; - else - nr[l] = 0; - } else + if (scanning_global_lru(sc)) + nr[l] = nr_scan_try_batch(scan, + &zone->lru[l].nr_saved_scan, + swap_cluster_max); + else nr[l] = scan; } @@ -1521,7 +1576,7 @@ static void shrink_zone(int priority, struct zone *zone, * Even if we did not try to evict anon pages at all, we want to * rebalance the anon lru active/inactive ratio. */ - if (inactive_anon_is_low(zone, sc)) + if (inactive_anon_is_low(zone, sc) && nr_swap_pages > 0) shrink_active_list(SWAP_CLUSTER_MAX, zone, sc, priority, 0); throttle_vm_writeout(sc->gfp_mask); @@ -1532,11 +1587,13 @@ static void shrink_zone(int priority, struct zone *zone, * try to reclaim pages from zones which will satisfy the caller's allocation * request. * - * We reclaim from a zone even if that zone is over pages_high. Because: + * We reclaim from a zone even if that zone is over high_wmark_pages(zone). + * Because: * a) The caller may be trying to free *extra* pages to satisfy a higher-order * allocation or - * b) The zones may be over pages_high but they must go *over* pages_high to - * satisfy the `incremental min' zone defense algorithm. + * b) The target zone may be at high_wmark_pages(zone) but the lower zones + * must go *over* high_wmark_pages(zone) to satisfy the `incremental min' + * zone defense algorithm. * * If a zone is deemed to be full of pinned pages then just give it a light * scan then give up on it. @@ -1742,7 +1799,7 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont, /* * For kswapd, balance_pgdat() will work across all this node's zones until - * they are all at pages_high. + * they are all at high_wmark_pages(zone). * * Returns the number of pages which were actually freed. * @@ -1755,11 +1812,11 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont, * the zone for when the problem goes away. * * kswapd scans the zones in the highmem->normal->dma direction. It skips - * zones which have free_pages > pages_high, but once a zone is found to have - * free_pages <= pages_high, we scan that zone and the lower zones regardless - * of the number of free pages in the lower zones. This interoperates with - * the page allocator fallback scheme to ensure that aging of pages is balanced - * across the zones. + * zones which have free_pages > high_wmark_pages(zone), but once a zone is + * found to have free_pages <= high_wmark_pages(zone), we scan that zone and the + * lower zones regardless of the number of free pages in the lower zones. This + * interoperates with the page allocator fallback scheme to ensure that aging + * of pages is balanced across the zones. */ static unsigned long balance_pgdat(pg_data_t *pgdat, int order) { @@ -1780,7 +1837,8 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order) }; /* * temp_priority is used to remember the scanning priority at which - * this zone was successfully refilled to free_pages == pages_high. + * this zone was successfully refilled to + * free_pages == high_wmark_pages(zone). */ int temp_priority[MAX_NR_ZONES]; @@ -1825,8 +1883,8 @@ loop_again: shrink_active_list(SWAP_CLUSTER_MAX, zone, &sc, priority, 0); - if (!zone_watermark_ok(zone, order, zone->pages_high, - 0, 0)) { + if (!zone_watermark_ok(zone, order, + high_wmark_pages(zone), 0, 0)) { end_zone = i; break; } @@ -1860,8 +1918,8 @@ loop_again: priority != DEF_PRIORITY) continue; - if (!zone_watermark_ok(zone, order, zone->pages_high, - end_zone, 0)) + if (!zone_watermark_ok(zone, order, + high_wmark_pages(zone), end_zone, 0)) all_zones_ok = 0; temp_priority[i] = priority; sc.nr_scanned = 0; @@ -1870,8 +1928,8 @@ loop_again: * We put equal pressure on every zone, unless one * zone has way too many pages free already. */ - if (!zone_watermark_ok(zone, order, 8*zone->pages_high, - end_zone, 0)) + if (!zone_watermark_ok(zone, order, + 8*high_wmark_pages(zone), end_zone, 0)) shrink_zone(priority, zone, &sc); reclaim_state->reclaimed_slab = 0; nr_slab = shrink_slab(sc.nr_scanned, GFP_KERNEL, @@ -2037,7 +2095,7 @@ void wakeup_kswapd(struct zone *zone, int order) return; pgdat = zone->zone_pgdat; - if (zone_watermark_ok(zone, order, zone->pages_low, 0, 0)) + if (zone_watermark_ok(zone, order, low_wmark_pages(zone), 0, 0)) return; if (pgdat->kswapd_max_order < order) pgdat->kswapd_max_order = order; @@ -2084,11 +2142,11 @@ static void shrink_all_zones(unsigned long nr_pages, int prio, l == LRU_ACTIVE_FILE)) continue; - zone->lru[l].nr_scan += (lru_pages >> prio) + 1; - if (zone->lru[l].nr_scan >= nr_pages || pass > 3) { + zone->lru[l].nr_saved_scan += (lru_pages >> prio) + 1; + if (zone->lru[l].nr_saved_scan >= nr_pages || pass > 3) { unsigned long nr_to_scan; - zone->lru[l].nr_scan = 0; + zone->lru[l].nr_saved_scan = 0; nr_to_scan = min(nr_pages, lru_pages); nr_reclaimed += shrink_list(l, nr_to_scan, zone, sc, prio); @@ -2290,6 +2348,48 @@ int sysctl_min_unmapped_ratio = 1; */ int sysctl_min_slab_ratio = 5; +static inline unsigned long zone_unmapped_file_pages(struct zone *zone) +{ + unsigned long file_mapped = zone_page_state(zone, NR_FILE_MAPPED); + unsigned long file_lru = zone_page_state(zone, NR_INACTIVE_FILE) + + zone_page_state(zone, NR_ACTIVE_FILE); + + /* + * It's possible for there to be more file mapped pages than + * accounted for by the pages on the file LRU lists because + * tmpfs pages accounted for as ANON can also be FILE_MAPPED + */ + return (file_lru > file_mapped) ? (file_lru - file_mapped) : 0; +} + +/* Work out how many page cache pages we can reclaim in this reclaim_mode */ +static long zone_pagecache_reclaimable(struct zone *zone) +{ + long nr_pagecache_reclaimable; + long delta = 0; + + /* + * If RECLAIM_SWAP is set, then all file pages are considered + * potentially reclaimable. Otherwise, we have to worry about + * pages like swapcache and zone_unmapped_file_pages() provides + * a better estimate + */ + if (zone_reclaim_mode & RECLAIM_SWAP) + nr_pagecache_reclaimable = zone_page_state(zone, NR_FILE_PAGES); + else + nr_pagecache_reclaimable = zone_unmapped_file_pages(zone); + + /* If we can't clean pages, remove dirty pages from consideration */ + if (!(zone_reclaim_mode & RECLAIM_WRITE)) + delta += zone_page_state(zone, NR_FILE_DIRTY); + + /* Watch for any possible underflows due to delta */ + if (unlikely(delta > nr_pagecache_reclaimable)) + delta = nr_pagecache_reclaimable; + + return nr_pagecache_reclaimable - delta; +} + /* * Try to free up some pages from this zone through reclaim. */ @@ -2324,9 +2424,7 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order) reclaim_state.reclaimed_slab = 0; p->reclaim_state = &reclaim_state; - if (zone_page_state(zone, NR_FILE_PAGES) - - zone_page_state(zone, NR_FILE_MAPPED) > - zone->min_unmapped_pages) { + if (zone_pagecache_reclaimable(zone) > zone->min_unmapped_pages) { /* * Free memory by calling shrink zone with increasing * priorities until we have enough memory freed. @@ -2384,20 +2482,18 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order) * if less than a specified percentage of the zone is used by * unmapped file backed pages. */ - if (zone_page_state(zone, NR_FILE_PAGES) - - zone_page_state(zone, NR_FILE_MAPPED) <= zone->min_unmapped_pages - && zone_page_state(zone, NR_SLAB_RECLAIMABLE) - <= zone->min_slab_pages) - return 0; + if (zone_pagecache_reclaimable(zone) <= zone->min_unmapped_pages && + zone_page_state(zone, NR_SLAB_RECLAIMABLE) <= zone->min_slab_pages) + return ZONE_RECLAIM_FULL; if (zone_is_all_unreclaimable(zone)) - return 0; + return ZONE_RECLAIM_FULL; /* * Do not scan if the allocation should not be delayed. */ if (!(gfp_mask & __GFP_WAIT) || (current->flags & PF_MEMALLOC)) - return 0; + return ZONE_RECLAIM_NOSCAN; /* * Only run zone reclaim on the local zone or on zones that do not @@ -2407,18 +2503,21 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order) */ node_id = zone_to_nid(zone); if (node_state(node_id, N_CPU) && node_id != numa_node_id()) - return 0; + return ZONE_RECLAIM_NOSCAN; if (zone_test_and_set_flag(zone, ZONE_RECLAIM_LOCKED)) - return 0; + return ZONE_RECLAIM_NOSCAN; + ret = __zone_reclaim(zone, gfp_mask, order); zone_clear_flag(zone, ZONE_RECLAIM_LOCKED); + if (!ret) + count_vm_event(PGSCAN_ZONE_RECLAIM_FAILED); + return ret; } #endif -#ifdef CONFIG_UNEVICTABLE_LRU /* * page_evictable - test whether a page is evictable * @page: the page to test @@ -2665,4 +2764,3 @@ void scan_unevictable_unregister_node(struct node *node) sysdev_remove_file(&node->sysdev, &attr_scan_unevictable_pages); } -#endif diff --git a/mm/vmstat.c b/mm/vmstat.c index 74d66db..138bed5 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -629,10 +629,8 @@ static const char * const vmstat_text[] = { "nr_active_anon", "nr_inactive_file", "nr_active_file", -#ifdef CONFIG_UNEVICTABLE_LRU "nr_unevictable", "nr_mlock", -#endif "nr_anon_pages", "nr_mapped", "nr_file_pages", @@ -675,6 +673,9 @@ static const char * const vmstat_text[] = { TEXTS_FOR_ZONES("pgscan_kswapd") TEXTS_FOR_ZONES("pgscan_direct") +#ifdef CONFIG_NUMA + "zone_reclaim_failed", +#endif "pginodesteal", "slabs_scanned", "kswapd_steal", @@ -687,7 +688,6 @@ static const char * const vmstat_text[] = { "htlb_buddy_alloc_success", "htlb_buddy_alloc_fail", #endif -#ifdef CONFIG_UNEVICTABLE_LRU "unevictable_pgs_culled", "unevictable_pgs_scanned", "unevictable_pgs_rescued", @@ -697,7 +697,6 @@ static const char * const vmstat_text[] = { "unevictable_pgs_stranded", "unevictable_pgs_mlockfreed", #endif -#endif }; static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, @@ -710,18 +709,14 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, "\n min %lu" "\n low %lu" "\n high %lu" - "\n scanned %lu (aa: %lu ia: %lu af: %lu if: %lu)" + "\n scanned %lu" "\n spanned %lu" "\n present %lu", zone_page_state(zone, NR_FREE_PAGES), - zone->pages_min, - zone->pages_low, - zone->pages_high, + min_wmark_pages(zone), + low_wmark_pages(zone), + high_wmark_pages(zone), zone->pages_scanned, - zone->lru[LRU_ACTIVE_ANON].nr_scan, - zone->lru[LRU_INACTIVE_ANON].nr_scan, - zone->lru[LRU_ACTIVE_FILE].nr_scan, - zone->lru[LRU_INACTIVE_FILE].nr_scan, zone->spanned_pages, zone->present_pages); |