From: Marco Elver elver@google.com
mainline inclusion from mainline-v5.14-rc1 commit 3d1a90ab0ed93362ec8ac85cf291243c87260c21 category: feature bugzilla: 181005 https://gitee.com/openeuler/kernel/issues/I4EUY7
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Unconditionally use unbound work queue, and not just if wq_power_efficient is true. Because if the system is idle, KFENCE may wait, and by being run on the unbound work queue, we permit the scheduler to make better scheduling decisions and not require pinning KFENCE to the same CPU upon waking up.
Link: https://lkml.kernel.org/r/20210521111630.472579-1-elver@google.com Fixes: 36f0b35d0894 ("kfence: use power-efficient work queue to run delayed work") Signed-off-by: Marco Elver elver@google.com Reported-by: Hillf Danton hdanton@sina.com Reviewed-by: Alexander Potapenko glider@google.com Cc: Dmitry Vyukov dvyukov@google.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Peng Liu liupeng256@huawei.com Reviewed-by: Kefeng Wang wangkefeng.wang@huawei.com
Signed-off-by: Chen Jun chenjun102@huawei.com --- mm/kfence/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/kfence/core.c b/mm/kfence/core.c index 4d21ac44d5d3..d7666ace9d2e 100644 --- a/mm/kfence/core.c +++ b/mm/kfence/core.c @@ -636,7 +636,7 @@ static void toggle_allocation_gate(struct work_struct *work) /* Disable static key and reset timer. */ static_branch_disable(&kfence_allocation_key); #endif - queue_delayed_work(system_power_efficient_wq, &kfence_timer, + queue_delayed_work(system_unbound_wq, &kfence_timer, msecs_to_jiffies(kfence_sample_interval)); } static DECLARE_DELAYED_WORK(kfence_timer, toggle_allocation_gate); @@ -666,7 +666,7 @@ void __init kfence_init(void) }
WRITE_ONCE(kfence_enabled, true); - queue_delayed_work(system_power_efficient_wq, &kfence_timer, 0); + queue_delayed_work(system_unbound_wq, &kfence_timer, 0); pr_info("initialized - using %lu bytes for %d objects at 0x%p-0x%p\n", KFENCE_POOL_SIZE, CONFIG_KFENCE_NUM_OBJECTS, (void *)__kfence_pool, (void *)(__kfence_pool + KFENCE_POOL_SIZE));