linux-kernel - [PATCH v2 0/2] Don't use coherent DMA buffers for ISO transfer

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20180622120419.7675-1-matwey@sai.msu.ru>
Date:   Fri, 22 Jun 2018 15:04:17 +0300
From:   "Matwey V. Kornilov" <matwey@....msu.ru>
To:     hverkuil@...all.nl, mchehab@...nel.org
Cc:     "Matwey V. Kornilov" <matwey.kornilov@...il.com>,
        rostedt@...dmis.org, mingo@...hat.com, isely@...ox.com,
        bhumirks@...il.com, colin.king@...onical.com,
        linux-media@...r.kernel.org, linux-kernel@...r.kernel.org,
        ezequiel@...labora.com, laurent.pinchart@...asonboard.com
Subject: [PATCH v2 0/2] Don't use coherent DMA buffers for ISO transfer

From: "Matwey V. Kornilov" <matwey.kornilov@...il.com>

DMA cocherency slows the transfer down on systems without hardware coherent
DMA. In order to demontrate this we introduce performance measurement
facilities in patch 1 and fix the performance issue in patch 2 in order to
obtain 5.5 times speedup.

Changes since v1:
 * trace_pwc_handler_exit() call moved to proper place
 * detailed description added for commit 1
 * additional output added to trace to track separate frames

Matwey V. Kornilov (2):
  media: usb: pwc: Introduce TRACE_EVENTs for pwc_isoc_handler()
  media: usb: pwc: Don't use coherent DMA buffers for ISO transfer

 drivers/media/usb/pwc/pwc-if.c | 19 +++++++------
 include/trace/events/pwc.h     | 64 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 9 deletions(-)
 create mode 100644 include/trace/events/pwc.h

-- 
2.16.4