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RCVD_VIA_SMTP_AUTH(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns] X-Spam-Flag: NO X-Spam-Score: -4.51 X-Rspamd-Queue-Id: 4DFD65BCCB X-Rspamd-Action: no action X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spam-Level: On 1/29/26 15:38, shengminghu512 wrote: > From: Shengming Hu > > alloc_pages_bulk_noprof() only fills NULL slots and already tracks how many > entries are pre-populated via nr_populated. > > The fast watermark check was adding nr_pages unconditionally, which can > overestimate the demand. Use (nr_pages - nr_populated) instead, as an > upper bound on the remaining pages this call can still allocate without > scanning the whole array. > > Signed-off-by: Shengming Hu Reviewed-by: Vlastimil Babka > --- > mm/page_alloc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 5fd9e4a03..90b978802 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5130,7 +5130,7 @@ unsigned long alloc_pages_bulk_noprof(gfp_t gfp, int preferred_nid, > > cond_accept_memory(zone, 0, alloc_flags); > retry_this_zone: > - mark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK) + nr_pages; > + mark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK) + nr_pages - nr_populated; > if (zone_watermark_fast(zone, 0, mark, > zonelist_zone_idx(ac.preferred_zoneref), > alloc_flags, gfp)) {