mirror of https://gitee.com/openkylin/linux.git
77ed2c5745
Currently, lowmemorykiller (LMK) is using TIF_MEMDIE for two purposes. One is to remember processes killed by LMK, and the other is to accelerate termination of processes killed by LMK. But since LMK is invoked as a memory shrinker function, there still should be some memory available. It is very likely that memory allocations by processes killed by LMK will succeed without using ALLOC_NO_WATERMARKS via TIF_MEMDIE. Even if their allocations cannot escape from memory allocation loop unless they use ALLOC_NO_WATERMARKS, lowmem_deathpending_timeout can guarantee forward progress by choosing next victim process. On the other hand, mark_oom_victim() assumes that it must be called with oom_lock held and it must not be called after oom_killer_disable() was called. But LMK is calling it without holding oom_lock and checking oom_killer_disabled. It is possible that LMK calls mark_oom_victim() due to allocation requests by kernel threads after current thread returned from oom_killer_disabled(). This will break synchronization for PM/suspend. This patch introduces per a task_struct flag for remembering processes killed by LMK, and replaces TIF_MEMDIE with that flag. By applying this patch, assumption by mark_oom_victim() becomes true. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Arve Hjonnevag <arve@android.com> Cc: Riley Andrews <riandrews@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
||
|---|---|---|
| .. | ||
| ion | ||
| trace | ||
| uapi | ||
| Kconfig | ||
| Makefile | ||
| TODO | ||
| ashmem.c | ||
| ashmem.h | ||
| lowmemorykiller.c | ||
| sw_sync.c | ||
| sw_sync.h | ||
| sync.c | ||
| sync.h | ||
| sync_debug.c | ||