diff options
| author | Christoph Hellwig <hch@lst.de> | 2025-11-13 09:39:45 +0100 |
|---|---|---|
| committer | Vlastimil Babka <vbabka@suse.cz> | 2025-11-13 17:10:38 +0100 |
| commit | b77fc08e393b77883bcb71825cfd49e44da44022 (patch) | |
| tree | 518aec1b9aba698a104dcec66b1ecbb5fa34f86b /mm | |
| parent | 5c829783e5f8dbb7ca6fce50c5c4a33f7c75d0d4 (diff) | |
mempool: add error injection support
Add a call to should_fail_ex that forces mempool to actually allocate
from the pool to stress the mempool implementation when enabled through
debugfs. By default should_fail{,_ex} prints a very verbose stack trace
that clutters the kernel log, slows down execution and triggers the
kernel bug detection in xfstests. Pass FAULT_NOWARN and print a
single-line message notating the caller instead so that full tests
can be run with fault injection.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://patch.msgid.link/20251113084022.1255121-5-hch@lst.de
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mempool.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/mm/mempool.c b/mm/mempool.c index 1f4701713203..5cf59779cc3d 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -9,7 +9,7 @@ * started by Ingo Molnar, Copyright (C) 2001 * debugging by David Rientjes, Copyright (C) 2015 */ - +#include <linux/fault-inject.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/highmem.h> @@ -20,6 +20,15 @@ #include <linux/writeback.h> #include "slab.h" +static DECLARE_FAULT_ATTR(fail_mempool_alloc); + +static int __init mempool_faul_inject_init(void) +{ + return PTR_ERR_OR_ZERO(fault_create_debugfs_attr("fail_mempool_alloc", + NULL, &fail_mempool_alloc)); +} +late_initcall(mempool_faul_inject_init); + #ifdef CONFIG_SLUB_DEBUG_ON static void poison_error(mempool_t *pool, void *element, size_t size, size_t byte) @@ -404,9 +413,15 @@ void *mempool_alloc_noprof(mempool_t *pool, gfp_t gfp_mask) gfp_temp = gfp_mask & ~(__GFP_DIRECT_RECLAIM|__GFP_IO); repeat_alloc: + if (should_fail_ex(&fail_mempool_alloc, 1, FAULT_NOWARN)) { + pr_info("forcing mempool usage for %pS\n", + (void *)_RET_IP_); + element = NULL; + } else { + element = pool->alloc(gfp_temp, pool->pool_data); + } - element = pool->alloc(gfp_temp, pool->pool_data); - if (likely(element != NULL)) + if (likely(element)) return element; spin_lock_irqsave(&pool->lock, flags); |