[PATCH 04/33] mm: allow mempool to fall back to memalloc reserves
From: Peter Zijlstra <hidden>
Date: 2007-10-30 16:24:55
Also in:
linux-mm, lkml
Allow the mempool to use the memalloc reserves when all else fails and the allocation context would otherwise allow it. Signed-off-by: Peter Zijlstra <redacted> --- mm/mempool.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) Index: linux-2.6/mm/mempool.c ===================================================================
--- linux-2.6.orig/mm/mempool.c
+++ linux-2.6/mm/mempool.c@@ -14,6 +14,7 @@ #include <linux/mempool.h> #include <linux/blkdev.h> #include <linux/writeback.h> +#include "internal.h" static void add_element(mempool_t *pool, void *element) {
@@ -204,7 +205,7 @@ void * mempool_alloc(mempool_t *pool, gf void *element; unsigned long flags; wait_queue_t wait; - gfp_t gfp_temp; + gfp_t gfp_temp, gfp_orig = gfp_mask; might_sleep_if(gfp_mask & __GFP_WAIT);
@@ -228,6 +229,15 @@ repeat_alloc: } spin_unlock_irqrestore(&pool->lock, flags); + /* if we really had right to the emergency reserves try those */ + if (gfp_to_alloc_flags(gfp_orig) & ALLOC_NO_WATERMARKS) { + if (gfp_temp & __GFP_NOMEMALLOC) { + gfp_temp &= ~(__GFP_NOMEMALLOC|__GFP_NOWARN); + goto repeat_alloc; + } else + gfp_temp |= __GFP_NOMEMALLOC|__GFP_NOWARN; + } + /* We must not sleep in the GFP_ATOMIC case */ if (!(gfp_mask & __GFP_WAIT)) return NULL; --