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-rw-r--r--mm/page_alloc.c118
1 files changed, 69 insertions, 49 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2c6d5f64feca..f3e0c69a97b7 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1864,14 +1864,14 @@ int move_freepages(struct zone *zone,
#endif
for (page = start_page; page <= end_page;) {
- /* Make sure we are not inadvertently changing nodes */
- VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page);
-
if (!pfn_valid_within(page_to_pfn(page))) {
page++;
continue;
}
+ /* Make sure we are not inadvertently changing nodes */
+ VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page);
+
if (!PageBuddy(page)) {
page++;
continue;
@@ -2583,30 +2583,22 @@ int __isolate_free_page(struct page *page, unsigned int order)
* Update NUMA hit/miss statistics
*
* Must be called with interrupts disabled.
- *
- * When __GFP_OTHER_NODE is set assume the node of the preferred
- * zone is the local node. This is useful for daemons who allocate
- * memory on behalf of other processes.
*/
-static inline void zone_statistics(struct zone *preferred_zone, struct zone *z,
- gfp_t flags)
+static inline void zone_statistics(struct zone *preferred_zone, struct zone *z)
{
#ifdef CONFIG_NUMA
- int local_nid = numa_node_id();
enum zone_stat_item local_stat = NUMA_LOCAL;
- if (unlikely(flags & __GFP_OTHER_NODE)) {
+ if (z->node != numa_node_id())
local_stat = NUMA_OTHER;
- local_nid = preferred_zone->node;
- }
- if (z->node == local_nid) {
+ if (z->node == preferred_zone->node)
__inc_zone_state(z, NUMA_HIT);
- __inc_zone_state(z, local_stat);
- } else {
+ else {
__inc_zone_state(z, NUMA_MISS);
__inc_zone_state(preferred_zone, NUMA_FOREIGN);
}
+ __inc_zone_state(z, local_stat);
#endif
}
@@ -2674,7 +2666,7 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
}
__count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
- zone_statistics(preferred_zone, zone, gfp_flags);
+ zone_statistics(preferred_zone, zone);
local_irq_restore(flags);
VM_BUG_ON_PAGE(bad_range(zone, page), page);
@@ -3531,12 +3523,13 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
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
@@ -3557,6 +3550,23 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
(__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
@@ -3716,6 +3726,13 @@ retry:
&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)
@@ -3728,6 +3745,16 @@ retry:
}
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:
@@ -3742,7 +3769,6 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
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 = {
@@ -3779,9 +3805,6 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
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);
@@ -3792,8 +3815,13 @@ retry_cpuset:
*/
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;
}
@@ -3802,6 +3830,7 @@ retry_cpuset:
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.
@@ -3813,21 +3842,10 @@ retry_cpuset:
* 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 &&
@@ -3904,8 +3922,8 @@ EXPORT_SYMBOL(free_pages);
* drivers to provide a backing region of memory for use as either an
* sk_buff->head, or to be used in the "frags" portion of skb_shared_info.
*/
-static struct page *__page_frag_refill(struct page_frag_cache *nc,
- gfp_t gfp_mask)
+static struct page *__page_frag_cache_refill(struct page_frag_cache *nc,
+ gfp_t gfp_mask)
{
struct page *page = NULL;
gfp_t gfp = gfp_mask;
@@ -3925,22 +3943,23 @@ static struct page *__page_frag_refill(struct page_frag_cache *nc,
return page;
}
-void __page_frag_drain(struct page *page, unsigned int order,
- unsigned int count)
+void __page_frag_cache_drain(struct page *page, unsigned int count)
{
VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
if (page_ref_sub_and_test(page, count)) {
+ unsigned int order = compound_order(page);
+
if (order == 0)
free_hot_cold_page(page, false);
else
__free_pages_ok(page, order);
}
}
-EXPORT_SYMBOL(__page_frag_drain);
+EXPORT_SYMBOL(__page_frag_cache_drain);
-void *__alloc_page_frag(struct page_frag_cache *nc,
- unsigned int fragsz, gfp_t gfp_mask)
+void *page_frag_alloc(struct page_frag_cache *nc,
+ unsigned int fragsz, gfp_t gfp_mask)
{
unsigned int size = PAGE_SIZE;
struct page *page;
@@ -3948,7 +3967,7 @@ void *__alloc_page_frag(struct page_frag_cache *nc,
if (unlikely(!nc->va)) {
refill:
- page = __page_frag_refill(nc, gfp_mask);
+ page = __page_frag_cache_refill(nc, gfp_mask);
if (!page)
return NULL;
@@ -3991,19 +4010,19 @@ refill:
return nc->va + offset;
}
-EXPORT_SYMBOL(__alloc_page_frag);
+EXPORT_SYMBOL(page_frag_alloc);
/*
* Frees a page fragment allocated out of either a compound or order 0 page.
*/
-void __free_page_frag(void *addr)
+void page_frag_free(void *addr)
{
struct page *page = virt_to_head_page(addr);
if (unlikely(put_page_testzero(page)))
__free_pages_ok(page, compound_order(page));
}
-EXPORT_SYMBOL(__free_page_frag);
+EXPORT_SYMBOL(page_frag_free);
static void *make_alloc_exact(unsigned long addr, unsigned int order,
size_t size)
@@ -7255,6 +7274,7 @@ int alloc_contig_range(unsigned long start, unsigned long end,
.zone = page_zone(pfn_to_page(start)),
.mode = MIGRATE_SYNC,
.ignore_skip_hint = true,
+ .gfp_mask = GFP_KERNEL,
};
INIT_LIST_HEAD(&cc.migratepages);