unsigned long count, struct list_head *list,
int migratetype, bool cold)
{
- int i;
+ int i, alloced = 0;
spin_lock(&zone->lock);
for (i = 0; i < count; ++i) {
else
list_add_tail(&page->lru, list);
list = &page->lru;
+ alloced++;
if (is_migrate_cma(get_pcppage_migratetype(page)))
__mod_zone_page_state(zone, NR_FREE_CMA_PAGES,
-(1 << order));
}
+
+ /*
+ * i pages were removed from the buddy list even if some leak due
+ * to check_pcp_refill failing so adjust NR_FREE_PAGES based
+ * on i. Do not confuse with 'alloced' which is the number of
+ * pages added to the pcp list.
+ */
__mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
spin_unlock(&zone->lock);
- return i;
+ return alloced;
}
#ifdef CONFIG_NUMA
struct page *page = NULL;
unsigned int alloc_flags;
unsigned long did_some_progress;
- enum compact_priority compact_priority = DEF_COMPACT_PRIORITY;
+ enum compact_priority compact_priority;
enum compact_result compact_result;
- int compaction_retries = 0;
- int no_progress_loops = 0;
+ int compaction_retries;
+ int no_progress_loops;
unsigned long alloc_start = jiffies;
unsigned int stall_timeout = 10 * HZ;
+ unsigned int cpuset_mems_cookie;
/*
* In the slowpath, we sanity check order to avoid ever trying to
(__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)))
gfp_mask &= ~__GFP_ATOMIC;
+retry_cpuset:
+ compaction_retries = 0;
+ no_progress_loops = 0;
+ compact_priority = DEF_COMPACT_PRIORITY;
+ cpuset_mems_cookie = read_mems_allowed_begin();
+ /*
+ * We need to recalculate the starting point for the zonelist iterator
+ * because we might have used different nodemask in the fast path, or
+ * there was a cpuset modification and we are retrying - otherwise we
+ * could end up iterating over non-eligible zones endlessly.
+ */
+ ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
+ ac->high_zoneidx, ac->nodemask);
+ if (!ac->preferred_zoneref->zone)
+ goto nopage;
+
+
/*
* The fast path uses conservative alloc_flags to succeed only until
* kswapd needs to be woken up, and to avoid the cost of setting up
&compaction_retries))
goto retry;
+ /*
+ * It's possible we raced with cpuset update so the OOM would be
+ * premature (see below the nopage: label for full explanation).
+ */
+ if (read_mems_allowed_retry(cpuset_mems_cookie))
+ goto retry_cpuset;
+
/* Reclaim has failed us, start killing things */
page = __alloc_pages_may_oom(gfp_mask, order, ac, &did_some_progress);
if (page)
}
nopage:
+ /*
+ * When updating a task's mems_allowed or mempolicy nodemask, it is
+ * possible to race with parallel threads in such a way that our
+ * allocation can fail while the mask is being updated. If we are about
+ * to fail, check if the cpuset changed during allocation and if so,
+ * retry.
+ */
+ if (read_mems_allowed_retry(cpuset_mems_cookie))
+ goto retry_cpuset;
+
warn_alloc(gfp_mask,
"page allocation failure: order:%u", order);
got_pg:
struct zonelist *zonelist, nodemask_t *nodemask)
{
struct page *page;
- unsigned int cpuset_mems_cookie;
unsigned int alloc_flags = ALLOC_WMARK_LOW;
gfp_t alloc_mask = gfp_mask; /* The gfp_t that was actually used for allocation */
struct alloc_context ac = {
if (IS_ENABLED(CONFIG_CMA) && ac.migratetype == MIGRATE_MOVABLE)
alloc_flags |= ALLOC_CMA;
-retry_cpuset:
- cpuset_mems_cookie = read_mems_allowed_begin();
-
/* Dirty zone balancing only done in the fast path */
ac.spread_dirty_pages = (gfp_mask & __GFP_WRITE);
*/
ac.preferred_zoneref = first_zones_zonelist(ac.zonelist,
ac.high_zoneidx, ac.nodemask);
- if (!ac.preferred_zoneref) {
+ if (!ac.preferred_zoneref->zone) {
page = NULL;
+ /*
+ * This might be due to race with cpuset_current_mems_allowed
+ * update, so make sure we retry with original nodemask in the
+ * slow path.
+ */
goto no_zone;
}
if (likely(page))
goto out;
+no_zone:
/*
* Runtime PM, block IO and its error handling path can deadlock
* because I/O on the device might not complete.
* Restore the original nodemask if it was potentially replaced with
* &cpuset_current_mems_allowed to optimize the fast-path attempt.
*/
- if (cpusets_enabled())
+ if (unlikely(ac.nodemask != nodemask))
ac.nodemask = nodemask;
- page = __alloc_pages_slowpath(alloc_mask, order, &ac);
-no_zone:
- /*
- * When updating a task's mems_allowed, it is possible to race with
- * parallel threads in such a way that an allocation can fail while
- * the mask is being updated. If a page allocation is about to fail,
- * check if the cpuset changed during allocation and if so, retry.
- */
- if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie))) {
- alloc_mask = gfp_mask;
- goto retry_cpuset;
- }
+ page = __alloc_pages_slowpath(alloc_mask, order, &ac);
out:
if (memcg_kmem_enabled() && (gfp_mask & __GFP_ACCOUNT) && page &&