This patch adds comm name and pid to warning messages printed by kmem_alloc(), kmem_zone_alloc() and xfs_buf_allocate_memory(). This will help telling which memory allocations (e.g. kernel worker threads, OOM victim tasks, neither) are stalling. [ 135.568662] Out of memory: Kill process 9593 (a.out) score 998 or sacrifice child [ 135.570195] Killed process 9593 (a.out) total-vm:4700kB, anon-rss:488kB, file-rss:0kB [ 137.473691] XFS: kworker/u16:29(383) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) [ 137.497662] XFS: a.out(8944) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) [ 137.598219] XFS: a.out(9658) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) [ 139.494529] XFS: kworker/u16:29(383) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) [ 139.517196] XFS: a.out(8944) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) [ 139.616396] XFS: a.out(9658) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) [ 141.512753] XFS: kworker/u16:29(383) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) [ 141.531421] XFS: a.out(8944) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) [ 141.633574] XFS: a.out(9658) possible memory allocation deadlock in xfs_buf_allocate_memory (mode:0x1250) (Strictly speaking, we want task_lock()/task_unlock() when reading comm name.) Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> --- fs/xfs/kmem.c | 6 ++++-- fs/xfs/xfs_buf.c | 3 ++- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/fs/xfs/kmem.c b/fs/xfs/kmem.c index 1fcf90d..95a5b76 100644 --- a/fs/xfs/kmem.c +++ b/fs/xfs/kmem.c @@ -54,8 +54,9 @@ kmem_alloc(size_t size, xfs_km_flags_t flags) if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP))) return ptr; if (!(++retries % 100)) - xfs_err(NULL, + xfs_err(NULL, "%s(%u) " "possible memory allocation deadlock in %s (mode:0x%x)", + current->comm, current->pid, __func__, lflags); congestion_wait(BLK_RW_ASYNC, HZ/50); } while (1); @@ -119,8 +120,9 @@ kmem_zone_alloc(kmem_zone_t *zone, xfs_km_flags_t flags) if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP))) return ptr; if (!(++retries % 100)) - xfs_err(NULL, + xfs_err(NULL, "%s(%u) " "possible memory allocation deadlock in %s (mode:0x%x)", + current->comm, current->pid, __func__, lflags); congestion_wait(BLK_RW_ASYNC, HZ/50); } while (1); diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index cbd4f91..5deb629 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -353,8 +353,9 @@ retry: * handle buffer allocation failures we can't do much. */ if (!(++retries % 100)) - xfs_err(NULL, + xfs_err(NULL, "%s(%u) " "possible memory allocation deadlock in %s (mode:0x%x)", + current->comm, current->pid, __func__, gfp_mask); XFS_STATS_INC(xb_page_retries); -- 1.8.3.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>