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| author | Benjamin Poirier <bpoirier@suse.com> | 2018-12-28 00:39:23 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-12-28 12:11:51 -0800 |
| commit | af3b854492f351d1ff3b4744a83bf5ff7eed4920 (patch) | |
| tree | 1f5eb6d523acd89f2d3b57598878fde1136cb060 /mm | |
| parent | ab41ee6879981b3d3a16a1079a33fa6fd043eb3c (diff) | |
| download | linux-af3b854492f351d1ff3b4744a83bf5ff7eed4920.tar.bz2 | |
mm/page_alloc.c: allow error injection
Model call chain after should_failslab(). Likewise, we can now use a
kprobe to override the return value of should_fail_alloc_page() and inject
allocation failures into alloc_page*().
This will allow injecting allocation failures using the BCC tools even
without building kernel with CONFIG_FAIL_PAGE_ALLOC and booting it with a
fail_page_alloc= parameter, which incurs some overhead even when failures
are not being injected. On the other hand, this patch adds an
unconditional call to should_fail_alloc_page() from page allocation
hotpath. That overhead should be rather negligible with
CONFIG_FAIL_PAGE_ALLOC=n when there's no kprobe attached, though.
[vbabka@suse.cz: changelog addition]
Link: http://lkml.kernel.org/r/20181214074330.18917-1-bpoirier@suse.com
Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/page_alloc.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 75865e1325b5..cde5dac6229a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3131,7 +3131,7 @@ static int __init setup_fail_page_alloc(char *str) } __setup("fail_page_alloc=", setup_fail_page_alloc); -static bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) +static bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) { if (order < fail_page_alloc.min_order) return false; @@ -3181,13 +3181,19 @@ late_initcall(fail_page_alloc_debugfs); #else /* CONFIG_FAIL_PAGE_ALLOC */ -static inline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) +static inline bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) { return false; } #endif /* CONFIG_FAIL_PAGE_ALLOC */ +static noinline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) +{ + return __should_fail_alloc_page(gfp_mask, order); +} +ALLOW_ERROR_INJECTION(should_fail_alloc_page, TRUE); + /* * Return true if free base pages are above 'mark'. For high-order checks it * will return true of the order-0 watermark is reached and there is at least |