mm/fs: delete PF_SWAPWRITE
PF_SWAPWRITE has been redundant since v3.2 commit ee72886d8ed5 ("mm:
vmscan: do not writeback filesystem pages in direct reclaim").
Coincidentally, NeilBrown's current patch "remove inode_congested()"
deletes may_write_to_inode(), which appeared to be the one function which
took notice of PF_SWAPWRITE. But if you study the old logic, and the
conditions under which may_write_to_inode() was called, you discover that
flag and function have been pointless for a decade.
Link: https://lkml.kernel.org/r/75e80e7-742d-e3bd-531-614db8961e4@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Jan Kara <jack@suse.de>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 5e14698..d416896 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -4457,7 +4457,7 @@ static int kswapd(void *p)
* us from recursively trying to free more memory as we're
* trying to free the first piece of memory in the first place).
*/
- tsk->flags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD;
+ tsk->flags |= PF_MEMALLOC | PF_KSWAPD;
set_freezable();
WRITE_ONCE(pgdat->kswapd_order, 0);
@@ -4508,7 +4508,7 @@ static int kswapd(void *p)
goto kswapd_try_sleep;
}
- tsk->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD);
+ tsk->flags &= ~(PF_MEMALLOC | PF_KSWAPD);
return 0;
}
@@ -4749,11 +4749,8 @@ static int __node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned in
fs_reclaim_acquire(sc.gfp_mask);
/*
* We need to be able to allocate from the reserves for RECLAIM_UNMAP
- * and we also need to be able to write out pages for RECLAIM_WRITE
- * and RECLAIM_UNMAP.
*/
noreclaim_flag = memalloc_noreclaim_save();
- p->flags |= PF_SWAPWRITE;
set_task_reclaim_state(p, &sc.reclaim_state);
if (node_pagecache_reclaimable(pgdat) > pgdat->min_unmapped_pages) {
@@ -4767,7 +4764,6 @@ static int __node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned in
}
set_task_reclaim_state(p, NULL);
- current->flags &= ~PF_SWAPWRITE;
memalloc_noreclaim_restore(noreclaim_flag);
fs_reclaim_release(sc.gfp_mask);
psi_memstall_leave(&pflags);
