diff options
| author | Johannes Weiner <hannes@cmpxchg.org> | 2025-04-16 09:45:39 -0400 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-04-17 20:10:09 -0700 |
| commit | 38448181459e24257b40d5258afdbaa3565e8cfc (patch) | |
| tree | b46dc11af491d3160e106ab1911911e77bb7ab20 /mm/page_alloc.c | |
| parent | 2db93a896fec7109302598cf45de3831340d9f53 (diff) | |
mm: vmscan: restore high-cpu watermark safety in kswapd
Vlastimil points out that commit a211c6550efc ("mm: page_alloc:
defrag_mode kswapd/kcompactd watermarks") switched kswapd from
zone_watermark_ok_safe() to the standard, percpu-cached version of reading
free pages, thus dropping the watermark safety precautions for systems
with high CPU counts (e.g. >212 cpus on 64G). Restore them.
Since zone_watermark_ok_safe() is no longer the right interface, and this
was the last caller of the function anyway, open-code the
zone_page_state_snapshot() conditional and delete the function.
Link: https://lkml.kernel.org/r/20250416135142.778933-2-hannes@cmpxchg.org
Fixes: a211c6550efc ("mm: page_alloc: defrag_mode kswapd/kcompactd watermarks")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 12 |
1 files changed, 0 insertions, 12 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e506e365d6f1..5669baf2a6fe 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3470,18 +3470,6 @@ static inline bool zone_watermark_fast(struct zone *z, unsigned int order, return false; } -bool zone_watermark_ok_safe(struct zone *z, unsigned int order, - unsigned long mark, int highest_zoneidx) -{ - long free_pages = zone_page_state(z, NR_FREE_PAGES); - - if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark) - free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES); - - return __zone_watermark_ok(z, order, mark, highest_zoneidx, 0, - free_pages); -} - #ifdef CONFIG_NUMA int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE; |