The patch titled
Subject: mm: swapoff: take notice of completion sooner
has been added to the -mm tree. Its filename is
mm-swapoff-take-notice-of-completion-sooner.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-swapoff-take-notice-of-completion-sooner.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-swapoff-take-notice-of-completion-sooner.patch
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there every 3-4 working days
------------------------------------------------------
From: Hugh Dickins <hughd@xxxxxxxxxx>
Subject: mm: swapoff: take notice of completion sooner
The old try_to_unuse() implementation was driven by find_next_to_unuse(),
which terminated as soon as all the swap had been freed. Add inuse_pages
checks now (alongside signal_pending()) to stop scanning mms and swap_map
once finished. The same ought to be done in shmem_unuse() too, but never
was before, and needs a different interface: so leave it as is for now.
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1904081258200.1523@eggly.anvils
Fixes: b56a2d8af914 ("mm: rid swapoff of quadratic complexity")
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: "Alex Xu (Hello71)" <alex_y_xu@xxxxxxxx>
Cc: Huang Ying <ying.huang@xxxxxxxxx>
Cc: Kelley Nielsen <kelleynnn@xxxxxxxxx>
Cc: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: Vineeth Pillai <vpillai@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/swapfile.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)
--- a/mm/swapfile.c~mm-swapoff-take-notice-of-completion-sooner
+++ a/mm/swapfile.c
@@ -2051,11 +2051,9 @@ retry:
spin_lock(&mmlist_lock);
p = &init_mm.mmlist;
- while ((p = p->next) != &init_mm.mmlist) {
- if (signal_pending(current)) {
- retval = -EINTR;
- break;
- }
+ while (si->inuse_pages &&
+ !signal_pending(current) &&
+ (p = p->next) != &init_mm.mmlist) {
mm = list_entry(p, struct mm_struct, mmlist);
if (!mmget_not_zero(mm))
@@ -2082,7 +2080,9 @@ retry:
mmput(prev_mm);
i = 0;
- while ((i = find_next_to_unuse(si, i, frontswap)) != 0) {
+ while (si->inuse_pages &&
+ !signal_pending(current) &&
+ (i = find_next_to_unuse(si, i, frontswap)) != 0) {
entry = swp_entry(type, i);
page = find_get_page(swap_address_space(entry), i);
@@ -2123,8 +2123,11 @@ retry:
* separate lists, and wait for those lists to be emptied; but it's
* easier and more robust (though cpu-intensive) just to keep retrying.
*/
- if (si->inuse_pages)
- goto retry;
+ if (si->inuse_pages) {
+ if (!signal_pending(current))
+ goto retry;
+ retval = -EINTR;
+ }
out:
return (retval == FRONTSWAP_PAGES_UNUSED) ? 0 : retval;
}
_
Patches currently in -mm which might be from hughd@xxxxxxxxxx are
mm-swapoff-shmem_find_swap_entries-filter-out-other-types.patch
mm-swapoff-remove-too-limiting-swap_unuse_max_tries.patch
mm-swapoff-take-notice-of-completion-sooner.patch
mm-swapoff-shmem_unuse-stop-eviction-without-igrab.patch
