From ba56e91c940146e99ac694c4c7cd7f2b4aaa565d Mon Sep 17 00:00:00 2001 From: "Seth, Rohit" Date: Sat, 29 Oct 2005 18:15:47 -0700 Subject: [PATCH] mm: page_alloc: increase size of per-cpu-pages Increase the page allocator's per-cpu magazines from 1/4MB to 1/2MB. Over 100+ runs for a workload, the difference in mean is about 2%. The best results for both are almost same. Though the max variation in results with 1/2MB is only 2.2%, whereas with 1/4MB it is 12%. Signed-off-by: Rohit Seth Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 94c864e..f799217 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1721,29 +1721,29 @@ static int __devinit zone_batchsize(struct zone *zone) /* * The per-cpu-pages pools are set to around 1000th of the - * size of the zone. But no more than 1/4 of a meg - there's - * no point in going beyond the size of L2 cache. + * size of the zone. But no more than 1/2 of a meg. * * OK, so we don't know how big the cache is. So guess. */ batch = zone->present_pages / 1024; - if (batch * PAGE_SIZE > 256 * 1024) - batch = (256 * 1024) / PAGE_SIZE; + if (batch * PAGE_SIZE > 512 * 1024) + batch = (512 * 1024) / PAGE_SIZE; batch /= 4; /* We effectively *= 4 below */ if (batch < 1) batch = 1; /* - * Clamp the batch to a 2^n - 1 value. Having a power - * of 2 value was found to be more likely to have - * suboptimal cache aliasing properties in some cases. + * We will be trying to allcoate bigger chunks of contiguous + * memory of the order of fls(batch). This should result in + * better cache coloring. * - * For example if 2 tasks are alternately allocating - * batches of pages, one task can end up with a lot - * of pages of one half of the possible page colors - * and the other with pages of the other colors. + * A sanity check also to ensure that batch is still in limits. */ - batch = (1 << fls(batch + batch/2)) - 1; + batch = (1 << fls(batch + batch/2)); + + if (fls(batch) >= (PAGE_SHIFT + MAX_ORDER - 2)) + batch = PAGE_SHIFT + ((MAX_ORDER - 1 - PAGE_SHIFT)/2); + return batch; } -- cgit v1.1 From e46a5e28c201f703c18b47b108bfddec44f897c4 Mon Sep 17 00:00:00 2001 From: "Seth, Rohit" Date: Sat, 29 Oct 2005 18:15:48 -0700 Subject: [PATCH] mm: set per-cpu-pages lower threshold to zero Set the low water mark for hot pages in pcp to zero. (akpm: for the life of me I cannot remember why we created pcp->low. Neither can Martin and the changelog is silent. Maybe it was just a brainfart, but I have this feeling that there was a reason. If not, we should remove the fields completely. We'll see.) Signed-off-by: Rohit Seth Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f799217..6066323 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1755,7 +1755,7 @@ inline void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) pcp = &p->pcp[0]; /* hot */ pcp->count = 0; - pcp->low = 2 * batch; + pcp->low = 0; pcp->high = 6 * batch; pcp->batch = max(1UL, 1 * batch); INIT_LIST_HEAD(&pcp->list); @@ -1764,7 +1764,7 @@ inline void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) pcp->count = 0; pcp->low = 0; pcp->high = 2 * batch; - pcp->batch = max(1UL, 1 * batch); + pcp->batch = max(1UL, batch/2); INIT_LIST_HEAD(&pcp->list); } -- cgit v1.1 From b5810039a54e5babf428e9a1e89fc1940fabff11 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Sat, 29 Oct 2005 18:16:12 -0700 Subject: [PATCH] core remove PageReserved Remove PageReserved() calls from core code by tightening VM_RESERVED handling in mm/ to cover PageReserved functionality. PageReserved special casing is removed from get_page and put_page. All setting and clearing of PageReserved is retained, and it is now flagged in the page_alloc checks to help ensure we don't introduce any refcount based freeing of Reserved pages. MAP_PRIVATE, PROT_WRITE of VM_RESERVED regions is tentatively being deprecated. We never completely handled it correctly anyway, and is be reintroduced in future if required (Hugh has a proof of concept). Once PageReserved() calls are removed from kernel/power/swsusp.c, and all arch/ and driver code, the Set and Clear calls, and the PG_reserved bit can be trivially removed. Last real user of PageReserved is swsusp, which uses PageReserved to determine whether a struct page points to valid memory or not. This still needs to be addressed (a generic page_is_ram() should work). A last caveat: the ZERO_PAGE is now refcounted and managed with rmap (and thus mapcounted and count towards shared rss). These writes to the struct page could cause excessive cacheline bouncing on big systems. There are a number of ways this could be addressed if it is an issue. Signed-off-by: Nick Piggin Refcount bug fix for filemap_xip.c Signed-off-by: Carsten Otte Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 6066323..0541288 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -114,7 +114,8 @@ static void bad_page(const char *function, struct page *page) 1 << PG_reclaim | 1 << PG_slab | 1 << PG_swapcache | - 1 << PG_writeback); + 1 << PG_writeback | + 1 << PG_reserved ); set_page_count(page, 0); reset_page_mapcount(page); page->mapping = NULL; @@ -244,7 +245,6 @@ static inline int page_is_buddy(struct page *page, int order) { if (PagePrivate(page) && (page_order(page) == order) && - !PageReserved(page) && page_count(page) == 0) return 1; return 0; @@ -327,7 +327,8 @@ static inline void free_pages_check(const char *function, struct page *page) 1 << PG_reclaim | 1 << PG_slab | 1 << PG_swapcache | - 1 << PG_writeback ))) + 1 << PG_writeback | + 1 << PG_reserved ))) bad_page(function, page); if (PageDirty(page)) __ClearPageDirty(page); @@ -455,7 +456,8 @@ static void prep_new_page(struct page *page, int order) 1 << PG_reclaim | 1 << PG_slab | 1 << PG_swapcache | - 1 << PG_writeback ))) + 1 << PG_writeback | + 1 << PG_reserved ))) bad_page(__FUNCTION__, page); page->flags &= ~(1 << PG_uptodate | 1 << PG_error | @@ -1016,7 +1018,7 @@ void __pagevec_free(struct pagevec *pvec) fastcall void __free_pages(struct page *page, unsigned int order) { - if (!PageReserved(page) && put_page_testzero(page)) { + if (put_page_testzero(page)) { if (order == 0) free_hot_page(page); else @@ -1674,7 +1676,7 @@ void __init memmap_init_zone(unsigned long size, int nid, unsigned long zone, continue; page = pfn_to_page(pfn); set_page_links(page, zone, nid, pfn); - set_page_count(page, 0); + set_page_count(page, 1); reset_page_mapcount(page); SetPageReserved(page); INIT_LIST_HEAD(&page->lru); -- cgit v1.1 From 4c21e2f2441dc5fbb957b030333f5a3f2d02dea7 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Sat, 29 Oct 2005 18:16:40 -0700 Subject: [PATCH] mm: split page table lock Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with a many-threaded application which concurrently initializes different parts of a large anonymous area. This patch corrects that, by using a separate spinlock per page table page, to guard the page table entries in that page, instead of using the mm's single page_table_lock. (But even then, page_table_lock is still used to guard page table allocation, and anon_vma allocation.) In this implementation, the spinlock is tucked inside the struct page of the page table page: with a BUILD_BUG_ON in case it overflows - which it would in the case of 32-bit PA-RISC with spinlock debugging enabled. Splitting the lock is not quite for free: another cacheline access. Ideally, I suppose we would use split ptlock only for multi-threaded processes on multi-cpu machines; but deciding that dynamically would have its own costs. So for now enable it by config, at some number of cpus - since the Kconfig language doesn't support inequalities, let preprocessor compare that with NR_CPUS. But I don't think it's worth being user-configurable: for good testing of both split and unsplit configs, split now at 4 cpus, and perhaps change that to 8 later. There is a benefit even for singly threaded processes: kswapd can be attacking one part of the mm while another part is busy faulting. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0541288..a2995a5 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -154,7 +154,7 @@ static void prep_compound_page(struct page *page, unsigned long order) struct page *p = page + i; SetPageCompound(p); - p->private = (unsigned long)page; + set_page_private(p, (unsigned long)page); } } @@ -174,7 +174,7 @@ static void destroy_compound_page(struct page *page, unsigned long order) if (!PageCompound(p)) bad_page(__FUNCTION__, page); - if (p->private != (unsigned long)page) + if (page_private(p) != (unsigned long)page) bad_page(__FUNCTION__, page); ClearPageCompound(p); } @@ -187,18 +187,18 @@ static void destroy_compound_page(struct page *page, unsigned long order) * So, we don't need atomic page->flags operations here. */ static inline unsigned long page_order(struct page *page) { - return page->private; + return page_private(page); } static inline void set_page_order(struct page *page, int order) { - page->private = order; + set_page_private(page, order); __SetPagePrivate(page); } static inline void rmv_page_order(struct page *page) { __ClearPagePrivate(page); - page->private = 0; + set_page_private(page, 0); } /* @@ -238,7 +238,7 @@ __find_combined_index(unsigned long page_idx, unsigned int order) * (a) the buddy is free && * (b) the buddy is on the buddy system && * (c) a page and its buddy have the same order. - * for recording page's order, we use page->private and PG_private. + * for recording page's order, we use page_private(page) and PG_private. * */ static inline int page_is_buddy(struct page *page, int order) @@ -264,7 +264,7 @@ static inline int page_is_buddy(struct page *page, int order) * parts of the VM system. * At each level, we keep a list of pages, which are heads of continuous * free pages of length of (1 << order) and marked with PG_Private.Page's - * order is recorded in page->private field. + * order is recorded in page_private(page) field. * So when we are allocating or freeing one, we can derive the state of the * other. That is, if we allocate a small block, and both were * free, the remainder of the region must be split into blocks. @@ -463,7 +463,7 @@ static void prep_new_page(struct page *page, int order) page->flags &= ~(1 << PG_uptodate | 1 << PG_error | 1 << PG_referenced | 1 << PG_arch_1 | 1 << PG_checked | 1 << PG_mappedtodisk); - page->private = 0; + set_page_private(page, 0); set_page_refs(page, order); kernel_map_pages(page, 1 << order, 1); } -- cgit v1.1 From ed8ece2ec8d3c2031b1a1a0737568bb0d49454e0 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 29 Oct 2005 18:16:50 -0700 Subject: [PATCH] memory hotplug prep: break out zone initialization If a zone is empty at boot-time and then hot-added to later, it needs to run the same init code that would have been run on it at boot. This patch breaks out zone table and per-cpu-pages functions for use by the hotplug code. You can almost see all of the free_area_init_core() function on one page now. :) Signed-off-by: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 98 ++++++++++++++++++++++++++++++++++----------------------- 1 file changed, 58 insertions(+), 40 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a2995a5..9a2fa81 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1875,6 +1875,60 @@ void __init setup_per_cpu_pageset() #endif +static __devinit +void zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages) +{ + int i; + struct pglist_data *pgdat = zone->zone_pgdat; + + /* + * The per-page waitqueue mechanism uses hashed waitqueues + * per zone. + */ + zone->wait_table_size = wait_table_size(zone_size_pages); + zone->wait_table_bits = wait_table_bits(zone->wait_table_size); + zone->wait_table = (wait_queue_head_t *) + alloc_bootmem_node(pgdat, zone->wait_table_size + * sizeof(wait_queue_head_t)); + + for(i = 0; i < zone->wait_table_size; ++i) + init_waitqueue_head(zone->wait_table + i); +} + +static __devinit void zone_pcp_init(struct zone *zone) +{ + int cpu; + unsigned long batch = zone_batchsize(zone); + + for (cpu = 0; cpu < NR_CPUS; cpu++) { +#ifdef CONFIG_NUMA + /* Early boot. Slab allocator not functional yet */ + zone->pageset[cpu] = &boot_pageset[cpu]; + setup_pageset(&boot_pageset[cpu],0); +#else + setup_pageset(zone_pcp(zone,cpu), batch); +#endif + } + printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%lu\n", + zone->name, zone->present_pages, batch); +} + +static __devinit void init_currently_empty_zone(struct zone *zone, + unsigned long zone_start_pfn, unsigned long size) +{ + struct pglist_data *pgdat = zone->zone_pgdat; + + zone_wait_table_init(zone, size); + pgdat->nr_zones = zone_idx(zone) + 1; + + zone->zone_mem_map = pfn_to_page(zone_start_pfn); + zone->zone_start_pfn = zone_start_pfn; + + memmap_init(size, pgdat->node_id, zone_idx(zone), zone_start_pfn); + + zone_init_free_lists(pgdat, zone, zone->spanned_pages); +} + /* * Set up the zone data structures: * - mark all pages reserved @@ -1884,8 +1938,8 @@ void __init setup_per_cpu_pageset() static void __init free_area_init_core(struct pglist_data *pgdat, unsigned long *zones_size, unsigned long *zholes_size) { - unsigned long i, j; - int cpu, nid = pgdat->node_id; + unsigned long j; + int nid = pgdat->node_id; unsigned long zone_start_pfn = pgdat->node_start_pfn; pgdat->nr_zones = 0; @@ -1895,7 +1949,6 @@ static void __init free_area_init_core(struct pglist_data *pgdat, for (j = 0; j < MAX_NR_ZONES; j++) { struct zone *zone = pgdat->node_zones + j; unsigned long size, realsize; - unsigned long batch; realsize = size = zones_size[j]; if (zholes_size) @@ -1915,19 +1968,7 @@ static void __init free_area_init_core(struct pglist_data *pgdat, zone->temp_priority = zone->prev_priority = DEF_PRIORITY; - batch = zone_batchsize(zone); - - for (cpu = 0; cpu < NR_CPUS; cpu++) { -#ifdef CONFIG_NUMA - /* Early boot. Slab allocator not functional yet */ - zone->pageset[cpu] = &boot_pageset[cpu]; - setup_pageset(&boot_pageset[cpu],0); -#else - setup_pageset(zone_pcp(zone,cpu), batch); -#endif - } - printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%lu\n", - zone_names[j], realsize, batch); + zone_pcp_init(zone); INIT_LIST_HEAD(&zone->active_list); INIT_LIST_HEAD(&zone->inactive_list); zone->nr_scan_active = 0; @@ -1938,32 +1979,9 @@ static void __init free_area_init_core(struct pglist_data *pgdat, if (!size) continue; - /* - * The per-page waitqueue mechanism uses hashed waitqueues - * per zone. - */ - zone->wait_table_size = wait_table_size(size); - zone->wait_table_bits = - wait_table_bits(zone->wait_table_size); - zone->wait_table = (wait_queue_head_t *) - alloc_bootmem_node(pgdat, zone->wait_table_size - * sizeof(wait_queue_head_t)); - - for(i = 0; i < zone->wait_table_size; ++i) - init_waitqueue_head(zone->wait_table + i); - - pgdat->nr_zones = j+1; - - zone->zone_mem_map = pfn_to_page(zone_start_pfn); - zone->zone_start_pfn = zone_start_pfn; - - memmap_init(size, nid, j, zone_start_pfn); - zonetable_add(zone, nid, j, zone_start_pfn, size); - + init_currently_empty_zone(zone, zone_start_pfn, size); zone_start_pfn += size; - - zone_init_free_lists(pgdat, zone, zone->spanned_pages); } } -- cgit v1.1 From c6a57e19e464db118dc4ab9cfe9e9748c6d630a0 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 29 Oct 2005 18:16:52 -0700 Subject: [PATCH] memory hotplug prep: fixup bad_range() When doing memory hotplug operations, the size of existing zones can obviously change. This means that zone->zone_{start_pfn,spanned_pages} can change. There are currently no locks that protect these structure members. However, they are rarely accessed at runtime. Outside of swsusp, the only place that I can find is bad_range(). So, split bad_range() up into two pieces: one that needs to be locked and anther that doesn't. Signed-off-by: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 9a2fa81..a51ef94 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -78,21 +78,37 @@ int min_free_kbytes = 1024; unsigned long __initdata nr_kernel_pages; unsigned long __initdata nr_all_pages; -/* - * Temporary debugging check for pages not lying within a given zone. - */ -static int bad_range(struct zone *zone, struct page *page) +static int page_outside_zone_boundaries(struct zone *zone, struct page *page) { if (page_to_pfn(page) >= zone->zone_start_pfn + zone->spanned_pages) return 1; if (page_to_pfn(page) < zone->zone_start_pfn) return 1; + + return 0; +} + +static int page_is_consistent(struct zone *zone, struct page *page) +{ #ifdef CONFIG_HOLES_IN_ZONE if (!pfn_valid(page_to_pfn(page))) - return 1; + return 0; #endif if (zone != page_zone(page)) + return 0; + + return 1; +} +/* + * Temporary debugging check for pages not lying within a given zone. + */ +static int bad_range(struct zone *zone, struct page *page) +{ + if (page_outside_zone_boundaries(zone, page)) return 1; + if (!page_is_consistent(zone, page)) + return 1; + return 0; } -- cgit v1.1 From 208d54e5513c0c02d85af0990901354c74364d5c Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 29 Oct 2005 18:16:52 -0700 Subject: [PATCH] memory hotplug locking: node_size_lock pgdat->node_size_lock is basically only neeeded in one place in the normal code: show_mem(), which is the arch-specific sysrq-m printing function. Strictly speaking, the architectures not doing memory hotplug do no need this locking in show_mem(). However, they are all included for completeness. This should also make any future consolidation of all of the implementations a little more straightforward. This lock is also held in the sparsemem code during a memory removal, as sections are invalidated. This is the place there pfn_valid() is made false for a memory area that's being removed. The lock is only required when doing pfn_valid() operations on memory which the user does not already have a reference on the page, such as in show_mem(). Signed-off-by: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 1 + 1 file changed, 1 insertion(+) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a51ef94..32fad6d 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1958,6 +1958,7 @@ static void __init free_area_init_core(struct pglist_data *pgdat, int nid = pgdat->node_id; unsigned long zone_start_pfn = pgdat->node_start_pfn; + pgdat_resize_init(pgdat); pgdat->nr_zones = 0; init_waitqueue_head(&pgdat->kswapd_wait); pgdat->kswapd_max_order = 0; -- cgit v1.1 From bdc8cb984576ab5b550c8b24c6fa111a873503e3 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 29 Oct 2005 18:16:53 -0700 Subject: [PATCH] memory hotplug locking: zone span seqlock See the "fixup bad_range()" patch for more information, but this actually creates a the lock to protect things making assumptions about a zone's size staying constant at runtime. Signed-off-by: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 32fad6d..817635f 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -80,12 +81,19 @@ unsigned long __initdata nr_all_pages; static int page_outside_zone_boundaries(struct zone *zone, struct page *page) { - if (page_to_pfn(page) >= zone->zone_start_pfn + zone->spanned_pages) - return 1; - if (page_to_pfn(page) < zone->zone_start_pfn) - return 1; + int ret = 0; + unsigned seq; + unsigned long pfn = page_to_pfn(page); - return 0; + do { + seq = zone_span_seqbegin(zone); + if (pfn >= zone->zone_start_pfn + zone->spanned_pages) + ret = 1; + else if (pfn < zone->zone_start_pfn) + ret = 1; + } while (zone_span_seqretry(zone, seq)); + + return ret; } static int page_is_consistent(struct zone *zone, struct page *page) @@ -1980,6 +1988,7 @@ static void __init free_area_init_core(struct pglist_data *pgdat, zone->name = zone_names[j]; spin_lock_init(&zone->lock); spin_lock_init(&zone->lru_lock); + zone_seqlock_init(zone); zone->zone_pgdat = pgdat; zone->free_pages = 0; -- cgit v1.1 From 3947be1969a9ce455ec30f60ef51efb10e4323d1 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 29 Oct 2005 18:16:54 -0700 Subject: [PATCH] memory hotplug: sysfs and add/remove functions This adds generic memory add/remove and supporting functions for memory hotplug into a new file as well as a memory hotplug kernel config option. Individual architecture patches will follow. For now, disable memory hotplug when swsusp is enabled. There's a lot of churn there right now. We'll fix it up properly once it calms down. Signed-off-by: Matt Tolentino Signed-off-by: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 817635f..183abf3 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1686,7 +1686,7 @@ static void __init calculate_zone_totalpages(struct pglist_data *pgdat, * up by free_all_bootmem() once the early boot process is * done. Non-atomic initialization, single-pass. */ -void __init memmap_init_zone(unsigned long size, int nid, unsigned long zone, +void __devinit memmap_init_zone(unsigned long size, int nid, unsigned long zone, unsigned long start_pfn) { struct page *page; @@ -2407,7 +2407,7 @@ static void setup_per_zone_lowmem_reserve(void) * that the pages_{min,low,high} values for each zone are set correctly * with respect to min_free_kbytes. */ -static void setup_per_zone_pages_min(void) +void setup_per_zone_pages_min(void) { unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10); unsigned long lowmem_pages = 0; -- cgit v1.1 From 2f96996de0eda378df2a5f857ee1ef615ae10a4f Mon Sep 17 00:00:00 2001 From: John Hawkes Date: Sat, 29 Oct 2005 18:17:01 -0700 Subject: [PATCH] mm: wider use of for_each_*cpu() In 'mm' change the explicit use of a for-loop using NR_CPUS into the general for_each_cpu() constructs. This widens the scope of potential future optimizations of the general constructs, as well as takes advantage of the existing optimizations of first_cpu() and next_cpu(), which is advantageous when the true CPU count is much smaller than NR_CPUS. Signed-off-by: John Hawkes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 183abf3..2dbdd98 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1331,12 +1331,9 @@ void show_free_areas(void) } else printk("\n"); - for (cpu = 0; cpu < NR_CPUS; ++cpu) { + for_each_cpu(cpu) { struct per_cpu_pageset *pageset; - if (!cpu_possible(cpu)) - continue; - pageset = zone_pcp(zone, cpu); for (temperature = 0; temperature < 2; temperature++) -- cgit v1.1