Le 03/11/2021 à 22:35, Christophe JAILLET a écrit :
Use 'percpu_ref_tryget_live_rcu()' instead of 'percpu_ref_tryget_live()' to save a few cycles when it is known that the rcu lock is already taken/released. Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> --- mm/memremap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/memremap.c b/mm/memremap.c index 84de22c14567..012e8d23d365 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -506,7 +506,7 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn, /* fall back to slow path lookup */ rcu_read_lock(); pgmap = xa_load(&pgmap_array, PHYS_PFN(phys)); - if (pgmap && !percpu_ref_tryget_live(pgmap->ref)) + if (pgmap && !percpu_ref_tryget_live_rcu(pgmap->ref)) pgmap = NULL; rcu_read_unlock();
Hi, gentle reminder. Is this patch useful? When I first posted it, percpu_ref_tryget_live_rcu() was really new. Now it is part of linux since 5.16. CJ
