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[217.229.16.64]) by smtp.gmail.com with ESMTPSA id z9sm4060180edr.61.2018.12.11.02.08.33 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 11 Dec 2018 02:08:33 -0800 (PST) Date: Tue, 11 Dec 2018 11:08:32 +0100 From: Thierry Reding To: Arnd Bergmann Cc: Mikko Perttunen , Dmitry Osipenko , Emil Goode , dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] host1x: cdma: use completion instead of semaphore Message-ID: <20181211100832.GE14426@ulmo> References: <20181210215119.1903413-1-arnd@arndb.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="r7U+bLA8boMOj+mD" Content-Disposition: inline In-Reply-To: <20181210215119.1903413-1-arnd@arndb.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --r7U+bLA8boMOj+mD Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Dec 10, 2018 at 10:51:04PM +0100, Arnd Bergmann wrote: > In this usage, the two are completely equivalent, but the > completion documents better what is going on, and we generally > try to avoid semaphores these days. >=20 > Signed-off-by: Arnd Bergmann > --- > drivers/gpu/host1x/cdma.c | 6 +++--- > drivers/gpu/host1x/cdma.h | 4 ++-- > 2 files changed, 5 insertions(+), 5 deletions(-) My understanding is that potentially many userspace processes could be blocking on this, which I think is the reason for it being a semaphore. Is the completion going to work for those cases as well? Thierry --r7U+bLA8boMOj+mD Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEiOrDCAFJzPfAjcif3SOs138+s6EFAlwPjKAACgkQ3SOs138+ s6F4YA//cuiEcBrx+Cqz4xqncvpwk/VeJ6Ag2er4y2er5lZL5OWJbSdKQuhw8ns7 l1OQ3VLF0Js9hLaDLEfdgxR3zzu0Ok5cyKeUH0bC1VZ8ces8ER1xHK24W7YeINAn ST8okJEV97mSHiiWe/p8nrYq5iIH7giUb9iZT57AX+6nxGAcg+XJ2gietauU2RUB RFSOcO2AQboWC9CWCcY0sW04IIP2+z4CMLeRDbe1TIGZzgyuG1p/WEuMqQ0AN+qv njAP8w9OyW1cltuoLqthFmdScsqc30H22RI/dISgFlLdYgu5PeGeYUeO5P+RB0Js iHk8T/wsr7+HTfnfpxZXYJnA1YtvIGEVe7RkTscAYjm9/UU//bke5OqjQJ4AOasn 83rXE9hhvNk+Vx7tzr0hQP20vm/3a5shTWWtOf/l8pJFhOqvMpJzZ1UBj4nz92XL 6ObY5XB8apbuFtqEVmUenOyZbRuJdpXOexerOJ82vBsu/WANpdOQP+9bo2Tdgtwv mNGWauAS3DJExL42UN2t6PnK7a9O/s7Wr0j7K9vhYNjZrgTsXOQcLMPLVhuJ3w8X gJvl3qJ8ZaGZcIh8MtQG3mG/qiALn3VwctxsIFkgX/a5IqTudIHsplq9/srLW0SX 7p1scDD9ON05LCWGW8J7DFgbS3vd2vL++IUwoYjudZTC2hG0GSI= =IYkF -----END PGP SIGNATURE----- --r7U+bLA8boMOj+mD--