diff options
| -rw-r--r-- | block/blk-ioc.c | 2 | ||||
| -rw-r--r-- | fs/fscache/page.c | 2 | ||||
| -rw-r--r-- | include/linux/radix-tree.h | 1 | ||||
| -rw-r--r-- | lib/radix-tree.c | 41 | ||||
| -rw-r--r-- | mm/filemap.c | 2 | ||||
| -rw-r--r-- | mm/shmem.c | 2 | ||||
| -rw-r--r-- | mm/swap_state.c | 4 |
7 files changed, 46 insertions, 8 deletions
diff --git a/block/blk-ioc.c b/block/blk-ioc.c index 4464c82..46cd7bd 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -367,7 +367,7 @@ struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q, if (!icq) return NULL; - if (radix_tree_preload(gfp_mask) < 0) { + if (radix_tree_maybe_preload(gfp_mask) < 0) { kmem_cache_free(et->icq_cache, icq); return NULL; } diff --git a/fs/fscache/page.c b/fs/fscache/page.c index 8702b73..73899c1 100644 --- a/fs/fscache/page.c +++ b/fs/fscache/page.c @@ -913,7 +913,7 @@ int __fscache_write_page(struct fscache_cookie *cookie, (1 << FSCACHE_OP_WAITING) | (1 << FSCACHE_OP_UNUSE_COOKIE); - ret = radix_tree_preload(gfp & ~__GFP_HIGHMEM); + ret = radix_tree_maybe_preload(gfp & ~__GFP_HIGHMEM); if (ret < 0) goto nomem_free; diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index ffc444c..4039407 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -231,6 +231,7 @@ unsigned long radix_tree_next_hole(struct radix_tree_root *root, unsigned long radix_tree_prev_hole(struct radix_tree_root *root, unsigned long index, unsigned long max_scan); int radix_tree_preload(gfp_t gfp_mask); +int radix_tree_maybe_preload(gfp_t gfp_mask); void radix_tree_init(void); void *radix_tree_tag_set(struct radix_tree_root *root, unsigned long index, unsigned int tag); diff --git a/lib/radix-tree.c b/lib/radix-tree.c index e796429..7811ed3 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -32,6 +32,7 @@ #include <linux/string.h> #include <linux/bitops.h> #include <linux/rcupdate.h> +#include <linux/hardirq.h> /* in_interrupt() */ #ifdef __KERNEL__ @@ -207,7 +208,12 @@ radix_tree_node_alloc(struct radix_tree_root *root) struct radix_tree_node *ret = NULL; gfp_t gfp_mask = root_gfp_mask(root); - if (!(gfp_mask & __GFP_WAIT)) { + /* + * Preload code isn't irq safe and it doesn't make sence to use + * preloading in the interrupt anyway as all the allocations have to + * be atomic. So just do normal allocation when in interrupt. + */ + if (!(gfp_mask & __GFP_WAIT) && !in_interrupt()) { struct radix_tree_preload *rtp; /* @@ -264,7 +270,7 @@ radix_tree_node_free(struct radix_tree_node *node) * To make use of this facility, the radix tree must be initialised without * __GFP_WAIT being passed to INIT_RADIX_TREE(). */ -int radix_tree_preload(gfp_t gfp_mask) +static int __radix_tree_preload(gfp_t gfp_mask) { struct radix_tree_preload *rtp; struct radix_tree_node *node; @@ -288,9 +294,40 @@ int radix_tree_preload(gfp_t gfp_mask) out: return ret; } + +/* + * Load up this CPU's radix_tree_node buffer with sufficient objects to + * ensure that the addition of a single element in the tree cannot fail. On + * success, return zero, with preemption disabled. On error, return -ENOMEM + * with preemption not disabled. + * + * To make use of this facility, the radix tree must be initialised without + * __GFP_WAIT being passed to INIT_RADIX_TREE(). + */ +int radix_tree_preload(gfp_t gfp_mask) +{ + /* Warn on non-sensical use... */ + WARN_ON_ONCE(!(gfp_mask & __GFP_WAIT)); + return __radix_tree_preload(gfp_mask); +} EXPORT_SYMBOL(radix_tree_preload); /* + * The same as above function, except we don't guarantee preloading happens. + * We do it, if we decide it helps. On success, return zero with preemption + * disabled. On error, return -ENOMEM with preemption not disabled. + */ +int radix_tree_maybe_preload(gfp_t gfp_mask) +{ + if (gfp_mask & __GFP_WAIT) + return __radix_tree_preload(gfp_mask); + /* Preloading doesn't help anything with this gfp mask, skip it */ + preempt_disable(); + return 0; +} +EXPORT_SYMBOL(radix_tree_maybe_preload); + +/* * Return the maximum key which can be store into a * radix tree with height HEIGHT. */ diff --git a/mm/filemap.c b/mm/filemap.c index 731a2c2..e607728 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -469,7 +469,7 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping, if (error) goto out; - error = radix_tree_preload(gfp_mask & ~__GFP_HIGHMEM); + error = radix_tree_maybe_preload(gfp_mask & ~__GFP_HIGHMEM); if (error == 0) { page_cache_get(page); page->mapping = mapping; @@ -1205,7 +1205,7 @@ repeat: gfp & GFP_RECLAIM_MASK); if (error) goto decused; - error = radix_tree_preload(gfp & GFP_RECLAIM_MASK); + error = radix_tree_maybe_preload(gfp & GFP_RECLAIM_MASK); if (!error) { error = shmem_add_to_page_cache(page, mapping, index, gfp, NULL); diff --git a/mm/swap_state.c b/mm/swap_state.c index f24ab0d..e6f15f8 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -122,7 +122,7 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask) { int error; - error = radix_tree_preload(gfp_mask); + error = radix_tree_maybe_preload(gfp_mask); if (!error) { error = __add_to_swap_cache(page, entry); radix_tree_preload_end(); @@ -328,7 +328,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, /* * call radix_tree_preload() while we can wait. */ - err = radix_tree_preload(gfp_mask & GFP_KERNEL); + err = radix_tree_maybe_preload(gfp_mask & GFP_KERNEL); if (err) break; |
