[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <df714a474d1358bf594f3f6dc02cdcf296cef40d.1391688720.git.agordeev@redhat.com>
Date: Thu, 6 Feb 2014 13:24:54 +0100
From: Alexander Gordeev <agordeev@...hat.com>
To: linux-kernel@...r.kernel.org
Cc: Alexander Gordeev <agordeev@...hat.com>,
Kent Overstreet <kmo@...erainc.com>,
Peter Zijlstra <peterz@...radead.org>,
Jens Axboe <axboe@...nel.dk>,
"Nicholas A. Bellinger" <nab@...ux-iscsi.org>
Subject: [PATCH RESEND 2/3] percpu_ida: Move waking up waiters out of atomic contexts
Currently percpu_ida_free() waikes up waiters always with local
interrupts disabled and sometimes with pool->lock held. Yet, it
does not appear there is any reason why it could not be done out
of these atomic contexts.
Signed-off-by: Alexander Gordeev <agordeev@...hat.com>
Cc: Kent Overstreet <kmo@...erainc.com>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Jens Axboe <axboe@...nel.dk>
Cc: "Nicholas A. Bellinger" <nab@...ux-iscsi.org>
Acked-by: Kent Overstreet <kmo@...erainc.com>
---
lib/percpu_ida.c | 9 ++++++---
1 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/lib/percpu_ida.c b/lib/percpu_ida.c
index fccfb28..c2fa3dc 100644
--- a/lib/percpu_ida.c
+++ b/lib/percpu_ida.c
@@ -229,6 +229,7 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
struct percpu_ida_cpu *tags;
unsigned long flags;
unsigned nr_free;
+ bool wake_up = false;
BUG_ON(tag >= pool->nr_tags);
@@ -247,7 +248,7 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
* Pairs with smp_rmb() in steal_tags()
*/
smp_wmb();
- wake_up(&pool->wait);
+ wake_up = true;
}
if (nr_free == pool->percpu_max_size) {
@@ -261,13 +262,15 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
move_tags(pool->freelist, &pool->nr_free,
tags->freelist, &tags->nr_free,
pool->percpu_batch_size);
-
- wake_up(&pool->wait);
+ wake_up = true;
}
spin_unlock(&pool->lock);
}
local_irq_restore(flags);
+
+ if (wake_up)
+ wake_up(&pool->wait);
}
EXPORT_SYMBOL_GPL(percpu_ida_free);
--
1.7.7.6
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists