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mm/page_alloc: track range of active PCP lists during bulk free

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free_pcppages_bulk() frees pages in a round-robin fashion.  Originally,
this was dealing only with migratetypes but storing high-order pages
means that there can be many more empty lists that are uselessly
checked.  Track the minimum and maximum active pindex to reduce the
search space.

Link: https://lkml.kernel.org/r/20220217002227.5739-3-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Aaron Lu <aaron.lu@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mel Gorman 2022-03-22 14:43:33 -07:00 committed by Linus Torvalds
parent ca7b59b1de
commit 35b6d770e6
1 changed files with 13 additions and 4 deletions
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17
mm/page_alloc.c
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@ -1447,6 +1447,8 @@ static void free_pcppages_bulk(struct zone *zone, int count,
struct per_cpu_pages *pcp)
{
int pindex = 0;
int min_pindex = 0;
int max_pindex = NR_PCP_LISTS - 1;
int batch_free = 0;
int nr_freed = 0;
unsigned int order;
@ -1472,13 +1474,20 @@ static void free_pcppages_bulk(struct zone *zone, int count,
*/
do {
batch_free++;
if (++pindex == NR_PCP_LISTS)
pindex = 0;
if (++pindex > max_pindex)
pindex = min_pindex;
list = &pcp->lists[pindex];
} while (list_empty(list));
if (!list_empty(list))
break;
if (pindex == max_pindex)
max_pindex--;
if (pindex == min_pindex)
min_pindex++;
} while (1);
/* This is the only non-empty list. Free them all. */
if (batch_free == NR_PCP_LISTS)
if (batch_free >= max_pindex - min_pindex)
batch_free = count;
order = pindex_to_order(pindex);