From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
To: bcrl@kvack.org, viro@zeniv.linux.org.uk
Cc: linux-aio@kvack.org, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org,
Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Subject: [PATCH] aio: Save a few cycles in 'lookup_ioctx()'
Date: Wed, 3 Nov 2021 22:31:35 +0100 [thread overview]
Message-ID: <0c3fcdaec33bb12b2367860dfab7ed4224ea000c.1635974999.git.christophe.jaillet@wanadoo.fr> (raw)
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@wanadoo.fr>
---
fs/aio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/aio.c b/fs/aio.c
index 9c81cf611d65..d189ea13e10a 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1062,7 +1062,7 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id)
id = array_index_nospec(id, table->nr);
ctx = rcu_dereference(table->table[id]);
if (ctx && ctx->user_id == ctx_id) {
- if (percpu_ref_tryget_live(&ctx->users))
+ if (percpu_ref_tryget_live_rcu(&ctx->users))
ret = ctx;
}
out:
--
2.30.2
next reply other threads:[~2021-11-03 21:31 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-03 21:31 Christophe JAILLET [this message]
2022-08-12 4:54 ` [PATCH] aio: Save a few cycles in 'lookup_ioctx()' Christophe JAILLET
2022-08-15 18:10 ` Jeff Moyer
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