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>
This commit is contained in:
Christoph Hellwig 2025-11-13 09:39:45 +01:00 committed by Vlastimil Babka
parent 5c829783e5
commit b77fc08e39
1 changed files with 18 additions and 3 deletions

View File

@ -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);
if (likely(element != NULL))
}
if (likely(element))
return element;
spin_lock_irqsave(&pool->lock, flags);