linux-kernel - Re: [PATCH v2 1/2] dmaengine: virt-dma: convert tasklet to BH workqueue for callback invocation

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

Message-ID: <13cb5cad-7ad4-40fd-a423-10187b327b8c@foss.st.com>
Date: Mon, 30 Jun 2025 13:07:10 +0200
From: Amelie Delaunay <amelie.delaunay@...s.st.com>
To: Alexander Kochetkov <al.kochet@...il.com>, Vinod Koul <vkoul@...nel.org>,
        <dmaengine@...r.kernel.org>, <linux-kernel@...r.kernel.org>
CC: Nishad Saraf <nishads@....com>, Lizhi Hou <lizhi.hou@....com>,
        Jacky Huang
	<ychuang3@...oton.com>,
        Shan-Chun Hung <schung@...oton.com>,
        Florian Fainelli
	<florian.fainelli@...adcom.com>,
        Ray Jui <rjui@...adcom.com>, Scott Branden
	<sbranden@...adcom.com>,
        Lars-Peter Clausen <lars@...afoo.de>,
        Paul Cercueil
	<paul@...pouillou.net>,
        Eugeniy Paltsev <Eugeniy.Paltsev@...opsys.com>,
        Manivannan Sadhasivam <mani@...nel.org>, Frank Li <Frank.Li@....com>,
        Zhou
 Wang <wangzhou1@...ilicon.com>,
        Longfang Liu <liulongfang@...wei.com>,
        Andy
 Shevchenko <andy@...nel.org>, Shawn Guo <shawnguo@...nel.org>,
        Sascha Hauer
	<s.hauer@...gutronix.de>,
        Pengutronix Kernel Team <kernel@...gutronix.de>,
        Fabio Estevam <festevam@...il.com>,
        Keguang Zhang <keguang.zhang@...il.com>,
        Sean Wang <sean.wang@...iatek.com>,
        Matthias Brugger
	<matthias.bgg@...il.com>,
        AngeloGioacchino Del Regno
	<angelogioacchino.delregno@...labora.com>,
        Andreas Färber
	<afaerber@...e.de>,
        Daniel Mack <daniel@...que.org>,
        Haojian Zhuang
	<haojian.zhuang@...il.com>,
        Robert Jarzmik <robert.jarzmik@...e.fr>,
        Paul
 Walmsley <paul.walmsley@...ive.com>,
        Samuel Holland
	<samuel.holland@...ive.com>,
        Orson Zhai <orsonzhai@...il.com>,
        Baolin Wang
	<baolin.wang@...ux.alibaba.com>,
        Chunyan Zhang <zhang.lyra@...il.com>,
        Patrice Chotard <patrice.chotard@...s.st.com>,
        Maxime Coquelin
	<mcoquelin.stm32@...il.com>,
        Alexandre Torgue <alexandre.torgue@...s.st.com>,
        Chen-Yu Tsai <wens@...e.org>,
        Jernej Skrabec <jernej.skrabec@...il.com>,
        Laxman Dewangan <ldewangan@...dia.com>,
        Jon Hunter <jonathanh@...dia.com>,
        Thierry Reding <thierry.reding@...il.com>,
        Peter Ujfalusi
	<peter.ujfalusi@...il.com>,
        Kunihiko Hayashi
	<hayashi.kunihiko@...ionext.com>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Dave Jiang <dave.jiang@...el.com>,
        Amit Vadhavana <av2082000@...il.com>,
        Uwe Kleine-König <u.kleine-koenig@...libre.com>,
        Ulf Hansson
	<ulf.hansson@...aro.org>,
        Md Sadre Alam <quic_mdalam@...cinc.com>,
        Casey
 Connolly <casey.connolly@...aro.org>,
        Kees Cook <kees@...nel.org>, Fenghua Yu
	<fenghua.yu@...el.com>,
        Jyothi Kumar Seerapu <quic_jseerapu@...cinc.com>
Subject: Re: [PATCH v2 1/2] dmaengine: virt-dma: convert tasklet to BH
 workqueue for callback invocation



On 6/16/25 14:48, Alexander Kochetkov wrote:
> Currently DMA callbacks are called from tasklet. However the tasklet is
> marked deprecated and must be replaced by BH workqueue. Tasklet callbacks
> are executed either in the Soft IRQ context or from ksoftirqd thread. BH
> workqueue work items are executed in the BH context. Changing tasklet to
> BH workqueue improved DMA callback latencies.
> 
> The commit changes virt-dma driver and all of its users:
> - tasklet is replaced to work_struct, tasklet callback updated accordingly
> - kill_tasklet() is replaced to cancel_work_sync()
> - added include of linux/interrupt.h where necessary
> 
> Tested on Pine64 (Allwinner A64 ARMv8) with sun6i-dma driver. All other
> drivers are changed similarly and tested for compilation.
> 
> Signed-off-by: Alexander Kochetkov <al.kochet@...il.com>
> ---
...
>   drivers/dma/stm32/stm32-dma.c                  |  1 +
>   drivers/dma/stm32/stm32-dma3.c                 |  1 +
>   drivers/dma/stm32/stm32-mdma.c                 |  1 +

For STM32:
Acked-by: Amelie Delaunay <amelie.delaunay@...s.st.com>
Tested-by: Amelie Delaunay <amelie.delaunay@...s.st.com>