From 18e027b1c7c6dd858b36305468251a5e4a6bcdf7 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Wed, 5 Jul 2023 20:34:38 -0700 Subject: bpf: Factor out inc/dec of active flag into helpers. Factor out local_inc/dec_return(&c->active) into helpers. No functional changes. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Hou Tao Link: https://lore.kernel.org/bpf/20230706033447.54696-6-alexei.starovoitov@gmail.com --- kernel/bpf/memalloc.c | 30 ++++++++++++++++++------------ 1 file changed, 18 insertions(+), 12 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 9693b1f8cbda..052fc801fb9f 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -154,17 +154,15 @@ static struct mem_cgroup *get_memcg(const struct bpf_mem_cache *c) #endif } -static void add_obj_to_free_list(struct bpf_mem_cache *c, void *obj) +static void inc_active(struct bpf_mem_cache *c, unsigned long *flags) { - unsigned long flags; - if (IS_ENABLED(CONFIG_PREEMPT_RT)) /* In RT irq_work runs in per-cpu kthread, so disable * interrupts to avoid preemption and interrupts and * reduce the chance of bpf prog executing on this cpu * when active counter is busy. */ - local_irq_save(flags); + local_irq_save(*flags); /* alloc_bulk runs from irq_work which will not preempt a bpf * program that does unit_alloc/unit_free since IRQs are * disabled there. There is no race to increment 'active' @@ -172,13 +170,25 @@ static void add_obj_to_free_list(struct bpf_mem_cache *c, void *obj) * bpf prog preempted this loop. */ WARN_ON_ONCE(local_inc_return(&c->active) != 1); - __llist_add(obj, &c->free_llist); - c->free_cnt++; +} + +static void dec_active(struct bpf_mem_cache *c, unsigned long flags) +{ local_dec(&c->active); if (IS_ENABLED(CONFIG_PREEMPT_RT)) local_irq_restore(flags); } +static void add_obj_to_free_list(struct bpf_mem_cache *c, void *obj) +{ + unsigned long flags; + + inc_active(c, &flags); + __llist_add(obj, &c->free_llist); + c->free_cnt++; + dec_active(c, flags); +} + /* Mostly runs from irq_work except __init phase. */ static void alloc_bulk(struct bpf_mem_cache *c, int cnt, int node) { @@ -300,17 +310,13 @@ static void free_bulk(struct bpf_mem_cache *c) int cnt; do { - if (IS_ENABLED(CONFIG_PREEMPT_RT)) - local_irq_save(flags); - WARN_ON_ONCE(local_inc_return(&c->active) != 1); + inc_active(c, &flags); llnode = __llist_del_first(&c->free_llist); if (llnode) cnt = --c->free_cnt; else cnt = 0; - local_dec(&c->active); - if (IS_ENABLED(CONFIG_PREEMPT_RT)) - local_irq_restore(flags); + dec_active(c, flags); if (llnode) enque_to_free(c, llnode); } while (cnt > (c->high_watermark + c->low_watermark) / 2); -- cgit v1.2.3