From: Andrea Parri <andrea.parri@amarulasolutions.com>
To: Marcel Holtmann <marcel@holtmann.org>,
Johan Hedberg <johan.hedberg@gmail.com>,
"David S. Miller" <davem@davemloft.net>
Cc: linux-bluetooth@vger.kernel.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org,
Jeffy Chen <jeffy.chen@rock-chips.com>,
Brian Norris <briannorris@chromium.org>,
AL Yu-Chen Cho <acho@suse.com>
Subject: [Question] bluetooth/{bnep,cmtp,hidp}: memory barriers
Date: Mon, 30 Jul 2018 05:10:30 +0200 [thread overview]
Message-ID: <20180730031030.GA9430@andrea> (raw)
Hi,
I'm currently puzzled by the the three calls to smp_mb__before_atomic()
in bnep_session(), cmtp_session() and hidp_session_run() respectively:
On the one hand, these barriers provide no guarantee on the subsequent
atomic_read(s->terminate) (as the comments preceding the barriers seem
to suggest), because atomic_read() is not a read-modify-write.
On the other hand, I'm currently unable to say *why such an "mb" would
be required: not being too familiar with this code, I figured I should
ask before sending a patch. ;-)
Andrea
next reply other threads:[~2018-07-30 3:10 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-30 3:10 Andrea Parri [this message]
2018-08-13 23:18 ` [Question] bluetooth/{bnep,cmtp,hidp}: memory barriers Brian Norris
2018-08-14 4:26 ` JeffyChen
2018-08-14 18:33 ` Andrea Parri
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