From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 05942C48260 for ; Thu, 8 Feb 2024 12:40:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:CC:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=AIk2cRkGrVo76q30FwuQCcIfNUX7wNeg9buanwMcdzo=; b=fMlgOuAvvkSBey R0r3hiG1awd+SHdLSneLgwpm4rONbhbnVbrScQLdg1il6OKe9WmrlwkenSFQyAf1zG1uE4n3Pz/+5 p17pC9usxjIUsIjMgwX7dP7nypiQDUzit7oANGiyNKqGfkGHu2V6s156yCr5NtOcN2oSgyLnLpSYX v3y7hbzKi02N6UMWV1CiJCzSza0nAwxNRtVmOf6loQXMPu54IUQyBCirEg/maCtdaehVW0LZ8detp +I2In6ARbNq/tmiJ6kaADZodgxvwlAYsnKPAOja/2golvCxQuu7bo2pf5o+JOPwo9vuh3EzDaNVaH XugWEpaVfwQIaNFOAFFQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rY3h9-0000000Dl0E-0HzP; Thu, 08 Feb 2024 12:39:59 +0000 Received: from frasgout.his.huawei.com ([185.176.79.56]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rY3h5-0000000DkyA-0nSW for linux-arm-kernel@lists.infradead.org; Thu, 08 Feb 2024 12:39:57 +0000 Received: from mail.maildlp.com (unknown [172.18.186.216]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4TVxLL487Tz6K5pX; Thu, 8 Feb 2024 20:36:26 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (unknown [7.191.163.240]) by mail.maildlp.com (Postfix) with ESMTPS id 29D9E140D1A; Thu, 8 Feb 2024 20:39:48 +0800 (CST) Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Thu, 8 Feb 2024 12:39:47 +0000 Date: Thu, 8 Feb 2024 12:39:46 +0000 From: Jonathan Cameron To: Yicong Yang CC: , , , , , , , , Subject: Re: [PATCH 6/7] drivers/perf: hisi_pcie: Merge find_related_event() and get_event_idx() Message-ID: <20240208123946.00006618@Huawei.com> In-Reply-To: <20240204074527.47110-7-yangyicong@huawei.com> References: <20240204074527.47110-1-yangyicong@huawei.com> <20240204074527.47110-7-yangyicong@huawei.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 X-Originating-IP: [10.202.227.76] X-ClientProxiedBy: lhrpeml100001.china.huawei.com (7.191.160.183) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240208_043955_645123_9779D197 X-CRM114-Status: GOOD ( 21.91 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, 4 Feb 2024 15:45:26 +0800 Yicong Yang wrote: > From: Junhao He > > The function xxx_find_related_event() scan all working events to find > related events. During this process, we also can find the idle counters. > If not found related events, return the first idle counter to simplify > the code. > > Signed-off-by: Junhao He > Signed-off-by: Yicong Yang A suggestion inline to avoid the magic HISI_PCIE_MAX_COUNTER value being used outside of the function. > --- > drivers/perf/hisilicon/hisi_pcie_pmu.c | 55 ++++++++++---------------- > 1 file changed, 21 insertions(+), 34 deletions(-) > > diff --git a/drivers/perf/hisilicon/hisi_pcie_pmu.c b/drivers/perf/hisilicon/hisi_pcie_pmu.c > index 1b45aeb82859..2edde66675e7 100644 > --- a/drivers/perf/hisilicon/hisi_pcie_pmu.c > +++ b/drivers/perf/hisilicon/hisi_pcie_pmu.c > @@ -397,16 +397,24 @@ static u64 hisi_pcie_pmu_read_counter(struct perf_event *event) > return hisi_pcie_pmu_readq(pcie_pmu, event->hw.event_base, idx); > } > > -static int hisi_pcie_pmu_find_related_event(struct hisi_pcie_pmu *pcie_pmu, > - struct perf_event *event) > +/* > + * Check all work events, if a relevant event is found then we return it > + * first, otherwise return the first idle counter (need to reset). > + */ > +static int hisi_pcie_pmu_get_event_idx(struct hisi_pcie_pmu *pcie_pmu, > + struct perf_event *event) > { > + int first_idle = HISI_PCIE_MAX_COUNTERS; int first_idle = -EAGAIN; > struct perf_event *sibling; > int idx; > > for (idx = 0; idx < HISI_PCIE_MAX_COUNTERS; idx++) { > sibling = pcie_pmu->hw_events[idx]; > - if (!sibling) > + if (!sibling) { > + if (first_idle == HISI_PCIE_MAX_COUNTERS) if (first_idle == -EAGAIN) > + first_idle = idx; > continue; > + } > > /* Related events must be used in group */ > if (hisi_pcie_pmu_cmp_event(sibling, event) && > @@ -414,19 +422,7 @@ static int hisi_pcie_pmu_find_related_event(struct hisi_pcie_pmu *pcie_pmu, > return idx; > } > > - return idx; > -} > - > -static int hisi_pcie_pmu_get_event_idx(struct hisi_pcie_pmu *pcie_pmu) > -{ > - int idx; > - > - for (idx = 0; idx < HISI_PCIE_MAX_COUNTERS; idx++) { > - if (!pcie_pmu->hw_events[idx]) > - return idx; > - } > - > - return -EINVAL; > + return first_idle; Then this will return -EAGAIN; > } > > static void hisi_pcie_pmu_event_update(struct perf_event *event) > @@ -552,27 +548,18 @@ static int hisi_pcie_pmu_add(struct perf_event *event, int flags) > > hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; > > - /* Check all working events to find a related event. */ > - idx = hisi_pcie_pmu_find_related_event(pcie_pmu, event); > - if (idx < 0) > - return idx; > - > - /* Current event shares an enabled counter with the related event */ > - if (idx < HISI_PCIE_MAX_COUNTERS) { > - hwc->idx = idx; > - goto start_count; > - } > - > - idx = hisi_pcie_pmu_get_event_idx(pcie_pmu); > - if (idx < 0) > - return idx; > + idx = hisi_pcie_pmu_get_event_idx(pcie_pmu, event); > + if (idx == HISI_PCIE_MAX_COUNTERS) > + return -EAGAIN; Perhaps simpler to handle first_idle == HISI_PCIE_MAX_COUNTERS as an error return in hisi_pcie_pmu_get_event_idx - see above. if (idx < 0) return idx; > > hwc->idx = idx; > - pcie_pmu->hw_events[idx] = event; > - /* Reset Counter to avoid previous statistic interference. */ > - hisi_pcie_pmu_reset_counter(pcie_pmu, idx); > > -start_count: > + /* No enabled counter found with related event, reset it */ > + if (!pcie_pmu->hw_events[idx]) { > + hisi_pcie_pmu_reset_counter(pcie_pmu, idx); > + pcie_pmu->hw_events[idx] = event; > + } > + > if (flags & PERF_EF_START) > hisi_pcie_pmu_start(event, PERF_EF_RELOAD); > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel