diff options
Diffstat (limited to 'recipes/linux/linux-omap-2.6.31/cache/copy-page-tweak.patch')
| -rw-r--r-- | recipes/linux/linux-omap-2.6.31/cache/copy-page-tweak.patch | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/recipes/linux/linux-omap-2.6.31/cache/copy-page-tweak.patch b/recipes/linux/linux-omap-2.6.31/cache/copy-page-tweak.patch new file mode 100644 index 0000000000..9da374041c --- /dev/null +++ b/recipes/linux/linux-omap-2.6.31/cache/copy-page-tweak.patch @@ -0,0 +1,169 @@ +Path: news.gmane.org!not-for-mail +From: "Kirill A. Shutemov" <kirill@shutemov.name> +Newsgroups: gmane.linux.ports.arm.kernel +Subject: [PATCH] ARM: copy_page.S: take into account the size of the cache line +Date: Wed, 2 Sep 2009 20:19:58 +0300 +Lines: 92 +Approved: news@gmane.org +Message-ID: <1251911998-3112-1-git-send-email-kirill__11898.5180197798$1251901300$gmane$org@shutemov.name> +References: <20090902132423.GA12595@n2100.arm.linux.org.uk> +NNTP-Posting-Host: lo.gmane.org +Mime-Version: 1.0 +Content-Type: text/plain; charset="us-ascii" +Content-Transfer-Encoding: 7bit +X-Trace: ger.gmane.org 1251901300 3930 80.91.229.12 (2 Sep 2009 14:21:40 GMT) +X-Complaints-To: usenet@ger.gmane.org +NNTP-Posting-Date: Wed, 2 Sep 2009 14:21:40 +0000 (UTC) +Cc: Bityutskiy Artem <Artem.Bityutskiy@nokia.com>, + "Kirill A. Shutemov" <kirill@shutemov.name>, + Siarhei Siamashka <siarhei.siamashka@nokia.com>, + Moiseichuk Leonid <leonid.moiseichuk@nokia.com>, + Koskinen Aaro <aaro.koskinen@nokia.com> +To: linux-arm-kernel@lists.infradead.org, + linux-kernel@vger.kernel.org +Original-X-From: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org Wed Sep 02 16:21:32 2009 +Return-path: <linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org> +Envelope-to: linux-arm-kernel@m.gmane.org +Original-Received: from bombadil.infradead.org ([18.85.46.34]) + by lo.gmane.org with esmtp (Exim 4.50) + id 1MiqiI-0003K3-An + for linux-arm-kernel@m.gmane.org; Wed, 02 Sep 2009 16:21:30 +0200 +Original-Received: from localhost ([::1] helo=bombadil.infradead.org) + by bombadil.infradead.org with esmtp (Exim 4.69 #1 (Red Hat Linux)) + id 1MiqhG-0005iZ-OK; Wed, 02 Sep 2009 14:20:26 +0000 +Original-Received: from mail-bw0-f222.google.com ([209.85.218.222]) + by bombadil.infradead.org with esmtp (Exim 4.69 #1 (Red Hat Linux)) + id 1Miqh8-0005LP-ED for linux-arm-kernel@lists.infradead.org; + Wed, 02 Sep 2009 14:20:23 +0000 +Original-Received: by bwz22 with SMTP id 22so788877bwz.18 + for <linux-arm-kernel@lists.infradead.org>; + Wed, 02 Sep 2009 07:20:06 -0700 (PDT) +Original-Received: by 10.204.162.143 with SMTP id v15mr6724283bkx.50.1251901206540; + Wed, 02 Sep 2009 07:20:06 -0700 (PDT) +Original-Received: from localhost.localdomain (viktor.cosmicparrot.net [217.152.255.14]) + by mx.google.com with ESMTPS id d13sm11540576fka.2.2009.09.02.07.20.05 + (version=SSLv3 cipher=RC4-MD5); Wed, 02 Sep 2009 07:20:05 -0700 (PDT) +X-Mailer: git-send-email 1.6.4.2 +In-Reply-To: <20090902132423.GA12595@n2100.arm.linux.org.uk> +X-CRM114-Version: 20090807-BlameThorstenAndJenny ( TRE 0.7.5 (LGPL) ) + MR-646709E3 +X-CRM114-CacheID: sfid-20090902_102018_607316_8AE98A04 +X-CRM114-Status: UNSURE ( 9.59 ) +X-CRM114-Notice: Please train this message. +X-Spam-Score: -4.2 (----) +X-Spam-Report: SpamAssassin version 3.2.5 on bombadil.infradead.org summary: + Content analysis details: (-4.2 points) + pts rule name description + ---- ---------------------- + -------------------------------------------------- + -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% + [score: 0.0000] + -1.6 AWL AWL: From: address is in the auto white-list +X-BeenThere: linux-arm-kernel@lists.infradead.org +X-Mailman-Version: 2.1.12 +Precedence: list +List-Id: <linux-arm-kernel.lists.infradead.org> +List-Unsubscribe: <http://lists.infradead.org/mailman/options/linux-arm-kernel>, + <mailto:linux-arm-kernel-request@lists.infradead.org?subject=unsubscribe> +List-Archive: <http://lists.infradead.org/pipermail/linux-arm-kernel/> +List-Post: <mailto:linux-arm-kernel@lists.infradead.org> +List-Help: <mailto:linux-arm-kernel-request@lists.infradead.org?subject=help> +List-Subscribe: <http://lists.infradead.org/mailman/listinfo/linux-arm-kernel>, + <mailto:linux-arm-kernel-request@lists.infradead.org?subject=subscribe> +Original-Sender: linux-arm-kernel-bounces@lists.infradead.org +Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org +Xref: news.gmane.org gmane.linux.ports.arm.kernel:65025 +Archived-At: <http://permalink.gmane.org/gmane.linux.ports.arm.kernel/65025> + +Optimized version of copy_page() was written with assumption that cache +line size is 32 bytes. On Cortex-A8 cache line size is 64 bytes. + +This patch tries to generalize copy_page() to work with any cache line +size if cache line size is multiple of 16 and page size is multiple of +two cache line size. + +After this optimization we've got ~25% speedup on OMAP3(tested in +userspace). + +There is test for kernelspace which trigger copy-on-write after fork(): + + #include <stdlib.h> + #include <string.h> + #include <unistd.h> + + #define BUF_SIZE (10000*4096) + #define NFORK 200 + + int main(int argc, char **argv) + { + char *buf = malloc(BUF_SIZE); + int i; + + memset(buf, 0, BUF_SIZE); + + for(i = 0; i < NFORK; i++) { + if (fork()) { + wait(NULL); + } else { + int j; + + for(j = 0; j < BUF_SIZE; j+= 4096) + buf[j] = (j & 0xFF) + 1; + break; + } + } + + free(buf); + return 0; + } + +Before optimization this test takes ~66 seconds, after optimization +takes ~56 seconds. + +Signed-off-by: Siarhei Siamashka <siarhei.siamashka@nokia.com> +Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name> +--- + arch/arm/lib/copy_page.S | 16 ++++++++-------- + 1 files changed, 8 insertions(+), 8 deletions(-) + +diff --git a/arch/arm/lib/copy_page.S b/arch/arm/lib/copy_page.S +index 6ae04db..6ee2f67 100644 +--- a/arch/arm/lib/copy_page.S ++++ b/arch/arm/lib/copy_page.S +@@ -12,8 +12,9 @@ + #include <linux/linkage.h> + #include <asm/assembler.h> + #include <asm/asm-offsets.h> ++#include <asm/cache.h> + +-#define COPY_COUNT (PAGE_SZ/64 PLD( -1 )) ++#define COPY_COUNT (PAGE_SZ / (2 * L1_CACHE_BYTES) PLD( -1 )) + + .text + .align 5 +@@ -26,17 +27,16 @@ + ENTRY(copy_page) + stmfd sp!, {r4, lr} @ 2 + PLD( pld [r1, #0] ) +- PLD( pld [r1, #32] ) ++ PLD( pld [r1, #L1_CACHE_BYTES] ) + mov r2, #COPY_COUNT @ 1 + ldmia r1!, {r3, r4, ip, lr} @ 4+1 +-1: PLD( pld [r1, #64] ) +- PLD( pld [r1, #96] ) +-2: stmia r0!, {r3, r4, ip, lr} @ 4 +- ldmia r1!, {r3, r4, ip, lr} @ 4+1 +- stmia r0!, {r3, r4, ip, lr} @ 4 +- ldmia r1!, {r3, r4, ip, lr} @ 4+1 ++1: PLD( pld [r1, #2 * L1_CACHE_BYTES]) ++ PLD( pld [r1, #3 * L1_CACHE_BYTES]) ++2: ++ .rept (2 * L1_CACHE_BYTES / 16 - 1) + stmia r0!, {r3, r4, ip, lr} @ 4 + ldmia r1!, {r3, r4, ip, lr} @ 4 ++ .endr + subs r2, r2, #1 @ 1 + stmia r0!, {r3, r4, ip, lr} @ 4 + ldmgtia r1!, {r3, r4, ip, lr} @ 4 +-- +1.6.4.2 |