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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Mailman-Approved-At: Fri, 29 Mar 2024 08:57:06 +1100 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: imx@lists.linux.dev, linux-hyperv@vger.kernel.org, oneukum@suse.com, duncan.sands@free.fr, hayashi.kunihiko@socionext.com, linux-mmc@vger.kernel.org, aubin.constans@microchip.com, linus.walleij@linaro.org, Frank.Li@nxp.com, linux-usb@vger.kernel.org, HaraldWelte@viatech.com, paul@crapouillou.net, linux-tegra@vger.kernel.org, netdev@vger.kernel.org, maintainers@bluecherrydvr.com, peter.ujfalusi@gmail.com, manivannan.sadhasivam@linaro.org, linux-riscv@lists.infradead.org, kys@microsoft.com, robert.jarzmik@free.fr, haijie1@huawei.com, linux-renesas-soc@vger.kernel.org, wei.liu@kernel.org, linux-omap@vger.kernel.org, florian.fainelli@broadcom.com, linux-rdma@vger.kernel.org, vireshk@kernel.org, jassisinghbrar@gmail.com, decui@microsoft.com, wangzhou1@hisilicon.com, jernej.skrabec@gmail.com, jh80.chung@samsung.com, zw@zh-kernel.org, wens@csie.org, stern@rowland.harvard.edu, linux-arm-msm@vger.kernel.org, orsonzhai@gmail.com, pierre@ossman.eu, linux-mips@vger.kernel.org, Eugeniy.Paltse v@synopsys.com, patrice.chotard@foss.st.com, asahi@lists.linux.dev, brucechang@via.com.tw, keescook@chromium.org, oakad@yahoo.com, sven@svenpeter.dev, rjui@broadcom.com, s.hauer@pengutronix.de, sean.wang@mediatek.com, linux-actions@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, haojian.zhuang@gmail.com, mirq-linux@rere.qmqm.pl, linux-mediatek@lists.infradead.org, linux-rpi-kernel@lists.infradead.org, baolin.wang@linux.alibaba.com, matthias.bgg@gmail.com, openipmi-developer@lists.sourceforge.net, mchehab@kernel.org, Allen Pais , linux-arm-kernel@lists.infradead.org, angelogioacchino.delregno@collabora.com, sbranden@broadcom.com, logang@deltatee.com, andersson@kernel.org, marcan@marcan.st, haiyangz@microsoft.com, linux-kernel@vger.kernel.org, leoyang.li@nxp.com, konrad.dybcio@linaro.org, linux-sunxi@lists.linux.dev, vkoul@kernel.org, linux-s390@vger.kernel.org, mhiramat@kernel.org, zhang.lyra@gmail.com, dmaengine@vger.kernel.org, manuel.lauss@gmail.com, linux-media@vger.kernel.org, shawnguo@kernel.org, afaerber@suse.de, daniel@zonque.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hello, On Thu, Mar 28, 2024 at 01:53:25PM +0100, Ulf Hansson wrote: > At this point we have suggested to drivers to switch to use threaded > irq handlers (and regular work queues if needed too). That said, > what's the benefit of using the BH work queue? BH workqueues should behave about the same as tasklets which have more limited interface and is subtly broken in an expensive-to-fix way (around freeing in-flight work item), so the plan is to replace tasklets with BH workqueues and remove tasklets from the kernel. The [dis]advantages of BH workqueues over threaded IRQs or regular threaded workqueues are the same as when you compare them to tasklets. No thread switching overhead, so latencies will be a bit tighter. Wheteher that actually matters really depends on the use case. Here, the biggest advantage is that it's mostly interchangeable with tasklets and can thus be swapped easily. Thanks. -- tejun