diff options
| author | Yisheng Xie <xieyisheng1@huawei.com> | 2017-11-29 16:11:08 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-29 18:40:43 -0800 |
| commit | bde5f6bc68db51128f875a756e9082a6c6ff7b4c (patch) | |
| tree | 76d26ad04100d9b378fc2ad520b299c69fef528f /mm/kmemleak.c | |
| parent | edbddb83a15b4361d8c3bf00aabee85fd3ef4d80 (diff) | |
| download | lwn-bde5f6bc68db51128f875a756e9082a6c6ff7b4c.tar.gz lwn-bde5f6bc68db51128f875a756e9082a6c6ff7b4c.zip | |
kmemleak: add scheduling point to kmemleak_scan()
kmemleak_scan() will scan struct page for each node and it can be really
large and resulting in a soft lockup. We have seen a soft lockup when
do scan while compile kernel:
watchdog: BUG: soft lockup - CPU#53 stuck for 22s! [bash:10287]
[...]
Call Trace:
kmemleak_scan+0x21a/0x4c0
kmemleak_write+0x312/0x350
full_proxy_write+0x5a/0xa0
__vfs_write+0x33/0x150
vfs_write+0xad/0x1a0
SyS_write+0x52/0xc0
do_syscall_64+0x61/0x1a0
entry_SYSCALL64_slow_path+0x25/0x25
Fix this by adding cond_resched every MAX_SCAN_SIZE.
Link: http://lkml.kernel.org/r/1511439788-20099-1-git-send-email-xieyisheng1@huawei.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/kmemleak.c')
| -rw-r--r-- | mm/kmemleak.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/mm/kmemleak.c b/mm/kmemleak.c index e4738d5e9b8c..3d4781756d50 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -1523,6 +1523,8 @@ static void kmemleak_scan(void) if (page_count(page) == 0) continue; scan_block(page, page + 1, NULL); + if (!(pfn % (MAX_SCAN_SIZE / sizeof(*page)))) + cond_resched(); } } put_online_mems(); |