From: "Chalamarla, Tirumalesh" <Tirumalesh.Chalamarla@caviumnetworks.com> To: Ganesh Mahendran <opensource.ganesh@gmail.com>, "catalin.marinas@arm.com" <catalin.marinas@arm.com>, "will.deacon@arm.com" <will.deacon@arm.com> Cc: "stable@vger.kernel.org" <stable@vger.kernel.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org> Subject: Re: [PATCH] Revert "arm64: Increase the max granular size" Date: Fri, 18 Mar 2016 21:05:37 +0000 [thread overview] Message-ID: <DA22064C-45A7-4F79-A433-84054AF182DF@caviumnetworks.com> (raw) In-Reply-To: <1458120743-12145-1-git-send-email-opensource.ganesh@gmail.com> On 3/16/16, 2:32 AM, "linux-arm-kernel on behalf of Ganesh Mahendran" <linux-arm-kernel-bounces@lists.infradead.org on behalf of opensource.ganesh@gmail.com> wrote: >Reverts commit 97303480753e ("arm64: Increase the max granular size"). > >The commit 97303480753e ("arm64: Increase the max granular size") will >degrade system performente in some cpus. > >We test wifi network throughput with iperf on Qualcomm msm8996 CPU: >---------------- >run on host: > # iperf -s >run on device: > # iperf -c <device-ip-addr> -t 100 -i 1 >---------------- > >Test result: >---------------- >with commit 97303480753e ("arm64: Increase the max granular size"): > 172MBits/sec > >without commit 97303480753e ("arm64: Increase the max granular size"): > 230MBits/sec >---------------- > >Some module like slab/net will use the L1_CACHE_SHIFT, so if we do not >set the parameter correctly, it may affect the system performance. > >So revert the commit. Is there any explanation why is this so? May be there is an alternative to this, apart from reverting the commit. Until now it seems L1_CACHE_SHIFT is the max of supported chips. But now we are making it 64byte, is there any reason why not 32. Thanks, Tirumalesh. > >Cc: stable@vger.kernel.org >Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com> >--- > arch/arm64/include/asm/cache.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h >index 5082b30..bde4499 100644 >--- a/arch/arm64/include/asm/cache.h >+++ b/arch/arm64/include/asm/cache.h >@@ -18,7 +18,7 @@ > > #include <asm/cachetype.h> > >-#define L1_CACHE_SHIFT 7 >+#define L1_CACHE_SHIFT 6 > #define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT) > > /* >-- >1.7.9.5 > > >_______________________________________________ >linux-arm-kernel mailing list >linux-arm-kernel@lists.infradead.org >http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
WARNING: multiple messages have this Message-ID (diff)
From: Tirumalesh.Chalamarla@caviumnetworks.com (Chalamarla, Tirumalesh) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH] Revert "arm64: Increase the max granular size" Date: Fri, 18 Mar 2016 21:05:37 +0000 [thread overview] Message-ID: <DA22064C-45A7-4F79-A433-84054AF182DF@caviumnetworks.com> (raw) In-Reply-To: <1458120743-12145-1-git-send-email-opensource.ganesh@gmail.com> On 3/16/16, 2:32 AM, "linux-arm-kernel on behalf of Ganesh Mahendran" <linux-arm-kernel-bounces at lists.infradead.org on behalf of opensource.ganesh@gmail.com> wrote: >Reverts commit 97303480753e ("arm64: Increase the max granular size"). > >The commit 97303480753e ("arm64: Increase the max granular size") will >degrade system performente in some cpus. > >We test wifi network throughput with iperf on Qualcomm msm8996 CPU: >---------------- >run on host: > # iperf -s >run on device: > # iperf -c <device-ip-addr> -t 100 -i 1 >---------------- > >Test result: >---------------- >with commit 97303480753e ("arm64: Increase the max granular size"): > 172MBits/sec > >without commit 97303480753e ("arm64: Increase the max granular size"): > 230MBits/sec >---------------- > >Some module like slab/net will use the L1_CACHE_SHIFT, so if we do not >set the parameter correctly, it may affect the system performance. > >So revert the commit. Is there any explanation why is this so? May be there is an alternative to this, apart from reverting the commit. Until now it seems L1_CACHE_SHIFT is the max of supported chips. But now we are making it 64byte, is there any reason why not 32. Thanks, Tirumalesh. > >Cc: stable at vger.kernel.org >Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com> >--- > arch/arm64/include/asm/cache.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h >index 5082b30..bde4499 100644 >--- a/arch/arm64/include/asm/cache.h >+++ b/arch/arm64/include/asm/cache.h >@@ -18,7 +18,7 @@ > > #include <asm/cachetype.h> > >-#define L1_CACHE_SHIFT 7 >+#define L1_CACHE_SHIFT 6 > #define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT) > > /* >-- >1.7.9.5 > > >_______________________________________________ >linux-arm-kernel mailing list >linux-arm-kernel at lists.infradead.org >http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2016-03-18 21:05 UTC|newest] Thread overview: 91+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-03-16 9:32 [PATCH] Revert "arm64: Increase the max granular size" Ganesh Mahendran 2016-03-16 9:32 ` Ganesh Mahendran 2016-03-16 10:07 ` Will Deacon 2016-03-16 10:07 ` Will Deacon 2016-03-16 13:06 ` Timur Tabi 2016-03-16 13:06 ` Timur Tabi 2016-03-16 14:03 ` Mark Rutland 2016-03-16 14:03 ` Mark Rutland 2016-03-16 14:35 ` Will Deacon 2016-03-16 14:35 ` Will Deacon 2016-03-16 14:54 ` Mark Rutland 2016-03-16 14:54 ` Mark Rutland 2016-03-16 14:18 ` Catalin Marinas 2016-03-16 14:18 ` Catalin Marinas 2016-03-16 15:26 ` Timur Tabi 2016-03-16 15:26 ` Timur Tabi 2016-03-17 14:27 ` Catalin Marinas 2016-03-17 14:27 ` Catalin Marinas 2016-03-17 14:49 ` Timur Tabi 2016-03-17 14:49 ` Timur Tabi 2016-03-17 15:37 ` Catalin Marinas 2016-03-17 15:37 ` Catalin Marinas 2016-03-17 16:03 ` Marc Zyngier 2016-03-17 16:03 ` Marc Zyngier 2016-03-17 18:07 ` Andrew Pinski 2016-03-17 18:07 ` Andrew Pinski 2016-03-17 18:34 ` Timur Tabi 2016-03-17 18:34 ` Timur Tabi 2016-03-17 18:37 ` Catalin Marinas 2016-03-17 18:37 ` Catalin Marinas 2016-03-18 21:05 ` Chalamarla, Tirumalesh [this message] 2016-03-18 21:05 ` Chalamarla, Tirumalesh 2016-03-18 21:05 ` Chalamarla, Tirumalesh 2016-03-21 1:56 ` Ganesh Mahendran 2016-03-21 1:56 ` Ganesh Mahendran 2016-03-21 1:56 ` Ganesh Mahendran 2016-03-21 17:14 ` Catalin Marinas 2016-03-21 17:14 ` Catalin Marinas 2016-03-21 17:14 ` Catalin Marinas 2016-03-21 17:23 ` Will Deacon 2016-03-21 17:23 ` Will Deacon 2016-03-21 17:23 ` Will Deacon 2016-03-21 17:33 ` Catalin Marinas 2016-03-21 17:33 ` Catalin Marinas 2016-03-21 17:33 ` Catalin Marinas 2016-03-21 17:39 ` Chalamarla, Tirumalesh 2016-03-21 17:39 ` Chalamarla, Tirumalesh 2016-03-21 17:39 ` Chalamarla, Tirumalesh [not found] ` <CAPub14-sFgx=oCHzJPb9h9b_V0rbn5UAMDNJ-yTkjhz38JPqMQ@mail.gmail.com> [not found] ` <10fef112-37f1-0a1b-b5af-435acd032f01@codeaurora.org> 2017-04-06 7:22 ` Imran Khan 2017-04-06 7:22 ` Imran Khan 2017-04-06 7:22 ` Imran Khan 2017-04-06 15:58 ` Catalin Marinas 2017-04-06 15:58 ` Catalin Marinas 2017-04-07 2:06 ` Ganesh Mahendran 2017-04-07 2:06 ` Ganesh Mahendran 2017-04-07 8:59 ` Catalin Marinas 2017-04-07 8:59 ` Catalin Marinas 2017-04-12 5:13 ` Imran Khan 2017-04-12 5:13 ` Imran Khan 2017-04-12 14:00 ` Chalamarla, Tirumalesh 2017-04-12 14:00 ` Chalamarla, Tirumalesh 2017-04-12 14:00 ` Chalamarla, Tirumalesh 2017-04-17 7:35 ` Imran Khan 2017-04-17 7:35 ` Imran Khan 2017-04-17 7:35 ` Imran Khan 2017-04-17 10:38 ` Sunil Kovvuri 2017-04-17 10:38 ` Sunil Kovvuri 2017-04-17 10:38 ` Sunil Kovvuri 2017-04-18 14:48 ` Catalin Marinas 2017-04-18 14:48 ` Catalin Marinas 2017-04-18 14:48 ` Catalin Marinas 2017-04-18 17:05 ` Sunil Kovvuri 2017-04-18 17:05 ` Sunil Kovvuri 2017-04-18 17:05 ` Sunil Kovvuri 2017-04-19 12:01 ` Catalin Marinas 2017-04-19 12:01 ` Catalin Marinas 2017-04-19 12:01 ` Catalin Marinas 2017-04-19 13:11 ` Sunil Kovvuri 2017-04-19 13:11 ` Sunil Kovvuri 2017-04-19 13:11 ` Sunil Kovvuri 2017-04-25 6:42 ` Ding Tianhong 2017-04-25 6:42 ` Ding Tianhong 2017-04-25 6:42 ` Ding Tianhong 2017-04-18 18:21 ` Chalamarla, Tirumalesh 2017-04-18 18:21 ` Chalamarla, Tirumalesh 2017-04-18 18:21 ` Chalamarla, Tirumalesh 2017-04-11 4:40 ` Jon Masters 2017-04-11 4:40 ` Jon Masters 2017-04-11 4:40 ` Jon Masters -- strict thread matches above, loose matches on Subject: below -- 2016-03-16 9:37 Ganesh Mahendran 2016-03-16 9:27 Ganesh Mahendran
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=DA22064C-45A7-4F79-A433-84054AF182DF@caviumnetworks.com \ --to=tirumalesh.chalamarla@caviumnetworks.com \ --cc=catalin.marinas@arm.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=opensource.ganesh@gmail.com \ --cc=stable@vger.kernel.org \ --cc=will.deacon@arm.com \ /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.