From: Peter Zijlstra <peterz@infradead.org>
To: Mikulas Patocka <mpatocka@redhat.com>
Cc: Bart Van Assche <bvanassche@acm.org>,
Mateusz Guzik <mguzik@redhat.com>, Ingo Molnar <mingo@redhat.com>,
linux-kernel@vger.kernel.org,
"Nicholas A. Bellinger" <nab@linux-iscsi.org>,
linux-scsi@vger.kernel.org, target-devel@vger.kernel.org
Subject: Re: [PATCH v2] kref: warn on uninitialized kref
Date: Mon, 19 May 2014 10:19:46 +0200 [thread overview]
Message-ID: <20140519081946.GV30445@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <alpine.LRH.2.02.1405171646290.32012@file01.intranet.prod.int.rdu2.redhat.com>
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On Sat, May 17, 2014 at 05:14:13PM -0400, Mikulas Patocka wrote:
> BTW. if we talk about performance - what about replacing:
>
> if (atomic_dec_and_test(&variable)) {
> ... release(object);
> }
>
> with this:
>
> if (atomic_read(&variable) == 1 || atomic_dec_and_test(&variable)) {
> barrier();
> ... release(object);
> }
That would completely wreck kref_get_unless_zero().
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next prev parent reply other threads:[~2014-05-19 8:19 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-17 10:49 [PATCH] target: fix memory leak on XCOPY Mikulas Patocka
2014-05-17 10:53 ` [PATCH] kref: warn on uninitialized kref Mikulas Patocka
2014-05-17 11:04 ` Mateusz Guzik
2014-05-17 12:36 ` Mikulas Patocka
2014-05-17 12:38 ` [PATCH v2] " Mikulas Patocka
2014-05-17 13:50 ` Bart Van Assche
2014-05-17 21:14 ` Mikulas Patocka
2014-05-18 7:17 ` Bart Van Assche
2014-05-19 8:19 ` Peter Zijlstra [this message]
2014-05-17 22:52 ` [PATCH] target: fix memory leak on XCOPY Nicholas A. Bellinger
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