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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam12 X-Rspam-User: X-Rspamd-Queue-Id: A92C980009 X-Stat-Signature: y4qaeex3eyccimhaj9te8f9r9yqmupqu X-HE-Tag: 1762869202-636667 X-HE-Meta: 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 jr3ZHdOT 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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 Acked-by: Vlastimil Babka --- mm/mempool.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/mm/mempool.c b/mm/mempool.c index 1f4701713203..76ba4d5e656f 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 #include #include #include @@ -20,6 +20,15 @@ #include #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 pool %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); -- 2.47.3