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[146.241.0.214]) by smtp.gmail.com with ESMTPSA id w18sm727733wru.54.2018.12.06.10.18.29 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 06 Dec 2018 10:18:30 -0800 (PST) From: Paolo Valente To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, ulf.hansson@linaro.org, linus.walleij@linaro.org, broonie@kernel.org, bfq-iosched@googlegroups.com, oleksandr@natalenko.name, federico@willer.it, Paolo Valente Subject: [PATCH BUGFIX 0/2] bfq: fix unbalanced decrements causing loss of throughput Date: Thu, 6 Dec 2018 19:18:17 +0100 Message-Id: <20181206181819.11148-1-paolo.valente@linaro.org> X-Mailer: git-send-email 2.16.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jens, the first patch in this series fixes an error in the decrementing of the counter of the number of groups with pending I/O. This wrong decrement caused loss of throughput or, less likely, of control on I/O. The second patch is a fix of some wrong comments, which somehow contributed to making the above bug more difficult to find. Thanks, Paolo Paolo Valente (2): block, bfq: fix decrement of num_active_groups block, bfq: fix comments on __bfq_deactivate_entity block/bfq-iosched.c | 76 +++++++++++++++++++++++++++++++++++++---------------- block/bfq-iosched.h | 51 +++++++++++++++++++++++++++++++++-- block/bfq-wf2q.c | 16 ++++++----- 3 files changed, 112 insertions(+), 31 deletions(-) -- 2.16.1