diff options
Diffstat (limited to 'mm/memcontrol.c')
-rw-r--r-- | mm/memcontrol.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 4b27e245a055..c823c35c2ed4 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3208,12 +3208,12 @@ void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, * accumulating over a page of vmstat data or when pgdat or idx * changes. */ - if (stock->cached_objcg != objcg) { + if (READ_ONCE(stock->cached_objcg) != objcg) { old = drain_obj_stock(stock); obj_cgroup_get(objcg); stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; - stock->cached_objcg = objcg; + WRITE_ONCE(stock->cached_objcg, objcg); stock->cached_pgdat = pgdat; } else if (stock->cached_pgdat != pgdat) { /* Flush the existing cached vmstat data */ @@ -3267,7 +3267,7 @@ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) local_lock_irqsave(&memcg_stock.stock_lock, flags); stock = this_cpu_ptr(&memcg_stock); - if (objcg == stock->cached_objcg && stock->nr_bytes >= nr_bytes) { + if (objcg == READ_ONCE(stock->cached_objcg) && stock->nr_bytes >= nr_bytes) { stock->nr_bytes -= nr_bytes; ret = true; } @@ -3279,7 +3279,7 @@ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) { - struct obj_cgroup *old = stock->cached_objcg; + struct obj_cgroup *old = READ_ONCE(stock->cached_objcg); if (!old) return NULL; @@ -3332,7 +3332,7 @@ static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) stock->cached_pgdat = NULL; } - stock->cached_objcg = NULL; + WRITE_ONCE(stock->cached_objcg, NULL); /* * The `old' objects needs to be released by the caller via * obj_cgroup_put() outside of memcg_stock_pcp::stock_lock. @@ -3343,10 +3343,11 @@ static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, struct mem_cgroup *root_memcg) { + struct obj_cgroup *objcg = READ_ONCE(stock->cached_objcg); struct mem_cgroup *memcg; - if (stock->cached_objcg) { - memcg = obj_cgroup_memcg(stock->cached_objcg); + if (objcg) { + memcg = obj_cgroup_memcg(objcg); if (memcg && mem_cgroup_is_descendant(memcg, root_memcg)) return true; } @@ -3365,10 +3366,10 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes, local_lock_irqsave(&memcg_stock.stock_lock, flags); stock = this_cpu_ptr(&memcg_stock); - if (stock->cached_objcg != objcg) { /* reset if necessary */ + if (READ_ONCE(stock->cached_objcg) != objcg) { /* reset if necessary */ old = drain_obj_stock(stock); obj_cgroup_get(objcg); - stock->cached_objcg = objcg; + WRITE_ONCE(stock->cached_objcg, objcg); stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; allow_uncharge = true; /* Allow uncharge when objcg changes */ |