While the nr_populated is non-zero, however the nr_account might be
zero if allocating fails. In this case, not to count event can save
some cycles.
And this commit extract the check of "page_array" from a while
statement to avoid unnecessary checks for it.
Signed-off-by: Yanfei Xu <yanfei.xu@xxxxxxxxxxxxx>
---
mm/page_alloc.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e9fd57ca4c1c..e25d508b85e9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5235,16 +5235,18 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid,
if (unlikely(nr_pages <= 0))
return 0;
- /*
- * Skip populated array elements to determine if any pages need
- * to be allocated before disabling IRQs.
- */
- while (page_array && nr_populated < nr_pages && page_array[nr_populated])
- nr_populated++;
+ if (page_array) {
+ /*
+ * Skip populated array elements to determine if any pages need
+ * to be allocated before disabling IRQs.
+ */
+ while (nr_populated < nr_pages && page_array[nr_populated])
+ nr_populated++;
- /* Already populated array? */
- if (unlikely(page_array && nr_pages - nr_populated == 0))
- return nr_populated;
+ /* Already populated array? */
+ if (unlikely(nr_pages - nr_populated == 0))
+ return nr_populated;
+ }
/* Use the single page allocator for one page. */
if (nr_pages - nr_populated == 1)
@@ -5319,9 +5321,10 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid,
local_unlock_irqrestore(&pagesets.lock, flags);
- __count_zid_vm_events(PGALLOC, zone_idx(zone), nr_account);
- zone_statistics(ac.preferred_zoneref->zone, zone, nr_account);
-
+ if (likely(nr_account)) {
+ __count_zid_vm_events(PGALLOC, zone_idx(zone), nr_account);
+ zone_statistics(ac.preferred_zoneref->zone, zone, nr_account);
+ }
return nr_populated;
failed_irq:
--
2.27.0
