From: Daniel Lezcano <daniel.lezcano@linaro.org> To: linux-acpi@vger.kernel.org, linux-pm@lists.linux-foundation.org, Lists Linaro-dev <linaro-dev@lists.linaro.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org> Cc: Kevin Hilman <khilman@ti.com>, Peter De Schrijver <pdeschrijver@nvidia.com>, Amit Kucheria <amit.kucheria@linaro.org>, linux-next@vger.kernel.org, Colin Cross <ccross@android.com>, Andrew Morton <akpm@linux-foundation.org>, Linus Torvalds <torvalds@linux-foundation.org>, Rob Lee <rob.lee@linaro.org> Subject: cpuidle future and improvements Date: Mon, 18 Jun 2012 10:40:45 +0200 [thread overview] Message-ID: <4FDEE98D.7010802@linaro.org> (raw) Dear all, A few weeks ago, Peter De Schrijver proposed a patch [1] to allow per cpu latencies. We had a discussion about this patchset because it reverse the modifications Deepthi did some months ago [2] and we may want to provide a different implementation. The Linaro Connect [3] event bring us the opportunity to meet people involved in the power management and the cpuidle area for different SoC. With the Tegra3 and big.LITTLE architecture, making per cpu latencies for cpuidle is vital. Also, the SoC vendors would like to have the ability to tune their cpu latencies through the device tree. We agreed in the following steps: 1. factor out / cleanup the cpuidle code as much as possible 2. better sharing of code amongst SoC idle drivers by moving common bits to core code 3. make the cpuidle_state structure contain only data 4. add a API to register latencies per cpu These four steps impacts all the architecture. I began the factor out code / cleanup [4] and that has been accepted upstream and I proposed some modifications [5] but I had a very few answers. The patch review are very slow and done at the last minute at the merge window and that makes code upstreaming very difficult. It is not a reproach, it is just how it is and I would like to propose a solution for that. I propose to host a cpuidle-next tree where all these modifications will be and where people can send patches against, preventing last minutes conflicts and perhaps Lenb will agree to pull from this tree. In the meantime, the tree will be part of the linux-next, the patches will be more widely tested and could be fixed earlier. Thanks -- Daniel [1] http://lwn.net/Articles/491257/ [2] http://lwn.net/Articles/464808/ [3] http://summit.linaro.org/ [4] http://www.mail-archive.com/linux-omap@vger.kernel.org/msg67033.html, http://www.spinics.net/lists/linux-pm/msg27330.html, http://comments.gmane.org/gmane.linux.ports.arm.omap/76311, http://www.digipedia.pl/usenet/thread/18885/11795/ [5] https://lkml.org/lkml/2012/6/8/375 -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog
WARNING: multiple messages have this Message-ID (diff)
From: Daniel Lezcano <daniel.lezcano@linaro.org> To: linux-acpi@vger.kernel.org, linux-pm@lists.linux-foundation.org, Lists Linaro-dev <linaro-dev@lists.linaro.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org> Cc: Amit Kucheria <amit.kucheria@linaro.org>, Deepthi Dharwar <deepthi@linux.vnet.ibm.com>, "lenb@kernel.org" <lenb@kernel.org>, Andrew Morton <akpm@linux-foundation.org>, Linus Torvalds <torvalds@linux-foundation.org>, Colin Cross <ccross@android.com>, Peter De Schrijver <pdeschrijver@nvidia.com>, Rob Lee <rob.lee@linaro.org>, rjw@sisk.pl, Kevin Hilman <khilman@ti.com>, linux-next@vger.kernel.org Subject: cpuidle future and improvements Date: Mon, 18 Jun 2012 10:40:45 +0200 [thread overview] Message-ID: <4FDEE98D.7010802@linaro.org> (raw) Dear all, A few weeks ago, Peter De Schrijver proposed a patch [1] to allow per cpu latencies. We had a discussion about this patchset because it reverse the modifications Deepthi did some months ago [2] and we may want to provide a different implementation. The Linaro Connect [3] event bring us the opportunity to meet people involved in the power management and the cpuidle area for different SoC. With the Tegra3 and big.LITTLE architecture, making per cpu latencies for cpuidle is vital. Also, the SoC vendors would like to have the ability to tune their cpu latencies through the device tree. We agreed in the following steps: 1. factor out / cleanup the cpuidle code as much as possible 2. better sharing of code amongst SoC idle drivers by moving common bits to core code 3. make the cpuidle_state structure contain only data 4. add a API to register latencies per cpu These four steps impacts all the architecture. I began the factor out code / cleanup [4] and that has been accepted upstream and I proposed some modifications [5] but I had a very few answers. The patch review are very slow and done at the last minute at the merge window and that makes code upstreaming very difficult. It is not a reproach, it is just how it is and I would like to propose a solution for that. I propose to host a cpuidle-next tree where all these modifications will be and where people can send patches against, preventing last minutes conflicts and perhaps Lenb will agree to pull from this tree. In the meantime, the tree will be part of the linux-next, the patches will be more widely tested and could be fixed earlier. Thanks -- Daniel [1] http://lwn.net/Articles/491257/ [2] http://lwn.net/Articles/464808/ [3] http://summit.linaro.org/ [4] http://www.mail-archive.com/linux-omap@vger.kernel.org/msg67033.html, http://www.spinics.net/lists/linux-pm/msg27330.html, http://comments.gmane.org/gmane.linux.ports.arm.omap/76311, http://www.digipedia.pl/usenet/thread/18885/11795/ [5] https://lkml.org/lkml/2012/6/8/375 -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog
next reply other threads:[~2012-06-18 8:40 UTC|newest] Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top 2012-06-18 8:40 Daniel Lezcano [this message] 2012-06-18 8:40 ` cpuidle future and improvements Daniel Lezcano 2012-06-18 11:54 ` Deepthi Dharwar 2012-06-18 12:35 ` Daniel Lezcano 2012-06-18 12:35 ` Daniel Lezcano 2012-06-18 12:53 ` Peter De Schrijver 2012-06-18 12:53 ` Peter De Schrijver 2012-06-18 12:55 ` Daniel Lezcano 2012-06-18 12:55 ` Daniel Lezcano 2012-06-18 13:06 ` Jean Pihet 2012-06-18 13:06 ` Jean Pihet 2012-06-18 13:26 ` Daniel Lezcano 2012-06-18 13:26 ` Daniel Lezcano 2012-06-18 13:30 ` [linux-pm] " a0393909 2012-06-25 12:58 ` Shilimkar, Santosh 2012-06-25 13:10 ` Daniel Lezcano 2012-06-25 13:10 ` Daniel Lezcano 2012-06-25 13:17 ` Shilimkar, Santosh 2012-06-25 13:27 ` linux-next : cpuidle - could you add my tree please Daniel Lezcano 2012-06-25 22:53 ` Stephen Rothwell 2012-07-02 9:09 ` Linus Walleij 2012-07-02 9:09 ` Linus Walleij 2012-07-02 12:51 ` Daniel Lezcano 2012-07-02 12:51 ` Daniel Lezcano 2012-07-02 19:49 ` Rafael J. Wysocki 2012-07-02 22:14 ` Daniel Lezcano 2012-07-03 8:59 ` Rafael J. Wysocki 2012-07-03 12:56 ` Daniel Lezcano 2012-07-03 13:19 ` Stephen Rothwell 2012-07-03 13:25 ` Daniel Lezcano 2012-07-03 13:25 ` Daniel Lezcano 2012-07-03 16:54 ` Rafael J. Wysocki 2012-07-05 13:33 ` Daniel Lezcano 2012-07-03 19:20 ` Linus Walleij 2012-07-03 19:20 ` Linus Walleij 2012-07-03 19:33 ` Rafael J. Wysocki 2012-07-03 19:33 ` Rafael J. Wysocki 2012-07-02 20:04 ` Rafael J. Wysocki 2012-07-02 20:04 ` Rafael J. Wysocki 2012-06-18 18:15 ` cpuidle future and improvements Colin Cross 2012-06-18 18:15 ` Colin Cross 2012-06-18 19:00 ` Daniel Lezcano 2012-06-18 19:00 ` Daniel Lezcano 2012-06-25 12:54 ` Daniel Lezcano 2012-07-11 14:00 ` [linux-pm] " Kevin Hilman
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=4FDEE98D.7010802@linaro.org \ --to=daniel.lezcano@linaro.org \ --cc=akpm@linux-foundation.org \ --cc=amit.kucheria@linaro.org \ --cc=ccross@android.com \ --cc=khilman@ti.com \ --cc=linaro-dev@lists.linaro.org \ --cc=linux-acpi@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-next@vger.kernel.org \ --cc=linux-pm@lists.linux-foundation.org \ --cc=pdeschrijver@nvidia.com \ --cc=rob.lee@linaro.org \ --cc=torvalds@linux-foundation.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.