From patchwork Sat Jul 4 05:06:43 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jisheng Zhang X-Patchwork-Id: 6717301 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 95B4AC05AC for ; Sat, 4 Jul 2015 05:11:17 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6AA602081A for ; Sat, 4 Jul 2015 05:11:16 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 70E2120807 for ; Sat, 4 Jul 2015 05:11:15 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZBFfr-0000aD-9b; Sat, 04 Jul 2015 05:07:35 +0000 Received: from mx0a-0016f401.pphosted.com ([67.231.148.174]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZBFfn-0000Yd-Nm for linux-arm-kernel@lists.infradead.org; Sat, 04 Jul 2015 05:07:32 +0000 Received: from pps.filterd (m0045849.ppops.net [127.0.0.1]) by mx0a-0016f401.pphosted.com (8.15.0.59/8.15.0.59) with SMTP id t6454ltJ004730; Fri, 3 Jul 2015 22:07:01 -0700 Received: from sc-owa.marvell.com ([199.233.58.135]) by mx0a-0016f401.pphosted.com with ESMTP id 1ve8xp80ge-1 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT); Fri, 03 Jul 2015 22:07:01 -0700 Received: from maili.marvell.com (10.93.76.83) by SC-OWA.marvell.com (10.93.76.28) with Microsoft SMTP Server id 8.3.327.1; Fri, 3 Jul 2015 22:07:01 -0700 Received: from xhacker.marvell.com (unknown [10.37.135.134]) by maili.marvell.com (Postfix) with ESMTP id 6B3C23F7040; Fri, 3 Jul 2015 22:07:00 -0700 (PDT) From: Jisheng Zhang To: , Subject: [PATCH v2] clocksource: dw_apb_timer: add dynamic irq flag to the timer Date: Sat, 4 Jul 2015 13:06:43 +0800 Message-ID: <1435986403-3797-1-git-send-email-jszhang@marvell.com> X-Mailer: git-send-email 2.1.4 MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2015-07-04_02:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 kscore.is_bulkscore=0 kscore.compositescore=1 compositescore=0.9 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 kscore.is_spamscore=0 rbsscore=0.9 spamscore=0 urlsuspectscore=0.9 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1506180000 definitions=main-1507040092 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150703_220731_791599_79EA9448 X-CRM114-Status: GOOD ( 10.84 ) X-Spam-Score: -2.6 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jisheng Zhang , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.8 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Commit d2348fb6fdc6 ("tick: Dynamically set broadcast irq affinity") adds one execllent feature CLOCK_EVT_FEAT_DYNIRQ to let the core set the interrupt affinity of the broadcast interrupt to the cpu which has the earliest expiry time. This patch adds CLOCK_EVT_FEAT_DYNIRQ flag to avoid unnecessary wakeups and IPIs when the dw_apb_timer is used as broadcast timer. A simple test: ~ # rm /tmp/test.sh ~ # cat > /tmp/test.sh cat /proc/interrupts for i in `seq 10` ; do sleep $i; done cat /proc/interrupts ~ # chmod +x /tmp/test.sh ~ # taskset 0x2 /tmp/test.sh without the patch: CPU0 CPU1 27: 115 36 GIC 27 arch_timer 45: 62 0 GIC 45 mmc0 160: 88 0 interrupt-controller 8 timer 227: 0 0 interrupt-controller 4 f7e81400.i2c 228: 0 0 interrupt-controller 5 f7e81800.i2c 229: 0 0 interrupt-controller 7 dw_spi65535 230: 0 0 interrupt-controller 21 f7e84000.i2c 231: 0 0 interrupt-controller 20 f7e84800.i2c 265: 445 0 interrupt-controller 8 serial IPI0: 0 0 CPU wakeup interrupts IPI1: 0 11 Timer broadcast interrupts IPI2: 56 104 Rescheduling interrupts IPI3: 0 0 Function call interrupts IPI4: 0 4 Single function call interrupts IPI5: 0 0 CPU stop interrupts IPI6: 25 27 IRQ work interrupts IPI7: 0 0 completion interrupts IPI8: 0 0 CPU backtrace Err: 0 CPU0 CPU1 27: 115 38 GIC 27 arch_timer 45: 62 0 GIC 45 mmc0 160: 160 0 interrupt-controller 8 timer 227: 0 0 interrupt-controller 4 f7e81400.i2c 228: 0 0 interrupt-controller 5 f7e81800.i2c 229: 0 0 interrupt-controller 7 dw_spi65535 230: 0 0 interrupt-controller 21 f7e84000.i2c 231: 0 0 interrupt-controller 20 f7e84800.i2c 265: 514 0 interrupt-controller 8 serial IPI0: 0 0 CPU wakeup interrupts IPI1: 0 83 Timer broadcast interrupts IPI2: 56 104 Rescheduling interrupts IPI3: 0 0 Function call interrupts IPI4: 0 4 Single function call interrupts IPI5: 0 0 CPU stop interrupts IPI6: 25 46 IRQ work interrupts IPI7: 0 0 completion interrupts IPI8: 0 0 CPU backtrace Err: 0 cpu0 get 160-88=72 timer interrupts, CPU1 got 83-11=72 broadcast timer IPIs So, overall system got 72+72=144 wake ups and 72 broadcast timer IPIs With the patch: CPU0 CPU1 27: 107 37 GIC 27 arch_timer 45: 62 0 GIC 45 mmc0 160: 66 7 interrupt-controller 8 timer 227: 0 0 interrupt-controller 4 f7e81400.i2c 228: 0 0 interrupt-controller 5 f7e81800.i2c 229: 0 0 interrupt-controller 7 dw_spi65535 230: 0 0 interrupt-controller 21 f7e84000.i2c 231: 0 0 interrupt-controller 20 f7e84800.i2c 265: 311 0 interrupt-controller 8 serial IPI0: 0 0 CPU wakeup interrupts IPI1: 2 4 Timer broadcast interrupts IPI2: 58 100 Rescheduling interrupts IPI3: 0 0 Function call interrupts IPI4: 0 4 Single function call interrupts IPI5: 0 0 CPU stop interrupts IPI6: 21 24 IRQ work interrupts IPI7: 0 0 completion interrupts IPI8: 0 0 CPU backtrace Err: 0 CPU0 CPU1 27: 107 39 GIC 27 arch_timer 45: 62 0 GIC 45 mmc0 160: 69 75 interrupt-controller 8 timer 227: 0 0 interrupt-controller 4 f7e81400.i2c 228: 0 0 interrupt-controller 5 f7e81800.i2c 229: 0 0 interrupt-controller 7 dw_spi65535 230: 0 0 interrupt-controller 21 f7e84000.i2c 231: 0 0 interrupt-controller 20 f7e84800.i2c 265: 380 0 interrupt-controller 8 serial IPI0: 0 0 CPU wakeup interrupts IPI1: 3 6 Timer broadcast interrupts IPI2: 60 100 Rescheduling interrupts IPI3: 0 0 Function call interrupts IPI4: 0 4 Single function call interrupts IPI5: 0 0 CPU stop interrupts IPI6: 21 45 IRQ work interrupts IPI7: 0 0 completion interrupts IPI8: 0 0 CPU backtrace Err: 0 cpu0 got 69-66=3, cpu1 got 75-7=68 timer interrupts. cpu0 got 3-2=1 broadcast timer IPIs, cpu1 got 6-4=2 broadcast timer IPIs. So, overall system got 3+68+1+2=74 wakeups and 1+2=3 broadcast timer IPIs This patch removes 50% wakeups and almost 100% broadcast timer IPIs! Signed-off-by: Jisheng Zhang --- drivers/clocksource/dw_apb_timer.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c index 35a8809..3381644 100644 --- a/drivers/clocksource/dw_apb_timer.c +++ b/drivers/clocksource/dw_apb_timer.c @@ -232,7 +232,8 @@ dw_apb_clockevent_init(int cpu, const char *name, unsigned rating, &dw_ced->ced); dw_ced->ced.min_delta_ns = clockevent_delta2ns(5000, &dw_ced->ced); dw_ced->ced.cpumask = cpumask_of(cpu); - dw_ced->ced.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + dw_ced->ced.features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ; dw_ced->ced.set_mode = apbt_set_mode; dw_ced->ced.set_next_event = apbt_next_event; dw_ced->ced.irq = dw_ced->timer.irq;