From aa182e64f16fc29a4984c2d79191b161888bbd9b Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 15 Jul 2014 07:08:10 +1000 Subject: [PATCH] Revert "xfs: block allocation work needs to be kswapd aware" This reverts commit 1f6d64829db78a7e1d63e15c9f48f0a5d2b5a679. This commit resulted in regressions in performance in low memory situations where kswapd was doing writeback of delayed allocation blocks. It resulted in significant parallelism of the kswapd work and with the special kswapd flags meant that hundreds of active allocation could dip into kswapd specific memory reserves and avoid being throttled. This cause a large amount of performance variation, as well as random OOM-killer invocations that didn't previously exist. Signed-off-by: Dave Chinner Reviewed-by: Brian Foster Signed-off-by: Dave Chinner --- fs/xfs/xfs_bmap_util.c | 16 +++------------- fs/xfs/xfs_bmap_util.h | 13 ++++++------- 2 files changed, 9 insertions(+), 20 deletions(-) diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 703b3ec1796c..057f671811d6 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -258,23 +258,14 @@ xfs_bmapi_allocate_worker( struct xfs_bmalloca *args = container_of(work, struct xfs_bmalloca, work); unsigned long pflags; - unsigned long new_pflags = PF_FSTRANS; - /* - * we are in a transaction context here, but may also be doing work - * in kswapd context, and hence we may need to inherit that state - * temporarily to ensure that we don't block waiting for memory reclaim - * in any way. - */ - if (args->kswapd) - new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD; - - current_set_flags_nested(&pflags, new_pflags); + /* we are in a transaction context here */ + current_set_flags_nested(&pflags, PF_FSTRANS); args->result = __xfs_bmapi_allocate(args); complete(args->done); - current_restore_flags_nested(&pflags, new_pflags); + current_restore_flags_nested(&pflags, PF_FSTRANS); } /* @@ -293,7 +284,6 @@ xfs_bmapi_allocate( args->done = &done; - args->kswapd = current_is_kswapd(); INIT_WORK_ONSTACK(&args->work, xfs_bmapi_allocate_worker); queue_work(xfs_alloc_wq, &args->work); wait_for_completion(&done); diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h index 075f72232a64..935ed2b24edf 100644 --- a/fs/xfs/xfs_bmap_util.h +++ b/fs/xfs/xfs_bmap_util.h @@ -50,13 +50,12 @@ struct xfs_bmalloca { xfs_extlen_t total; /* total blocks needed for xaction */ xfs_extlen_t minlen; /* minimum allocation size (blocks) */ xfs_extlen_t minleft; /* amount must be left after alloc */ - bool eof; /* set if allocating past last extent */ - bool wasdel; /* replacing a delayed allocation */ - bool userdata;/* set if is user data */ - bool aeof; /* allocated space at eof */ - bool conv; /* overwriting unwritten extents */ - bool stack_switch; - bool kswapd; /* allocation in kswapd context */ + char eof; /* set if allocating past last extent */ + char wasdel; /* replacing a delayed allocation */ + char userdata;/* set if is user data */ + char aeof; /* allocated space at eof */ + char conv; /* overwriting unwritten extents */ + char stack_switch; int flags; struct completion *done; struct work_struct work; -- 2.20.1