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Modified description from the commit to reflect this patch changes: Provide the inner part of refill_stock() as __refill_stock() without disabling interrupts. This eases the integration of local_lock_t where recursive locking must be avoided. Open code __memcg_kmem_uncharge() in drain_obj_stock() and obj_cgroup_release() and use __refill_stock(). The caller of drain_obj_stock() and obj_cgroup_release() already disables interrupts. Signed-off-by: Zachary Goldstein --- mm/memcontrol.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 5dd77e260c25..d61918cc44c1 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -260,6 +260,8 @@ struct cgroup_subsys_state *vmpressure_to_css(struct vmpressure *vmpr) #ifdef CONFIG_MEMCG_KMEM static DEFINE_SPINLOCK(objcg_lock); +static void __refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages); + static void obj_cgroup_release(struct percpu_ref *ref) { struct obj_cgroup *objcg = container_of(ref, struct obj_cgroup, refcnt); @@ -294,8 +296,12 @@ static void obj_cgroup_release(struct percpu_ref *ref) spin_lock_irqsave(&objcg_lock, flags); memcg = obj_cgroup_memcg(objcg); - if (nr_pages) - __memcg_kmem_uncharge(memcg, nr_pages); + if (nr_pages) { + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) + page_counter_uncharge(&memcg->kmem, nr_pages); + + __refill_stock(memcg, nr_pages); + } list_del(&objcg->list); mem_cgroup_put(memcg); spin_unlock_irqrestore(&objcg_lock, flags); @@ -2319,12 +2325,9 @@ static void drain_local_stock(struct work_struct *dummy) * Cache charges(val) to local per_cpu area. * This will be consumed by consume_stock() function, later. */ -static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) +static void __refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) { struct memcg_stock_pcp *stock; - unsigned long flags; - - local_lock_irqsave(&memcg_stock.lock, flags); stock = this_cpu_ptr(&memcg_stock); if (stock->cached != memcg) { /* reset if necessary */ @@ -2336,7 +2339,14 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) if (stock->nr_pages > MEMCG_CHARGE_BATCH) drain_stock(stock); +} +static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) +{ + unsigned long flags; + + local_lock_irqsave(&memcg_stock.lock, flags); + __refill_stock(memcg, nr_pages); local_unlock_irqrestore(&memcg_stock.lock, flags); } @@ -3179,7 +3189,11 @@ static void drain_obj_stock(struct memcg_stock_pcp *stock) goto retry; rcu_read_unlock(); - __memcg_kmem_uncharge(memcg, nr_pages); + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) + page_counter_uncharge(&memcg->kmem, nr_pages); + + __refill_stock(memcg, nr_pages); + css_put(&memcg->css); } -- 2.39.2