From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2612D14296 for ; Thu, 22 Feb 2024 03:00:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.187 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708570849; cv=none; b=H8KPVf94/dLFcCvPPt69LvJoL0RJGVy4LMjo5Xv7AlmtlaAa0AG1xG6iVmdIYxC8YN2NaZhxXug6R2OLxHVV7xInrYiY+B6dadW0iCBHzi3T0fWC1scFKQVUSzu3DjVFugciFPrYU5xBSDZ1sA5/DLO3Um02EPY3map+3UfS+N0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708570849; c=relaxed/simple; bh=616jFScVP4GMXLqtmGKWYqcPAkBoWZIGY0vG7QqeQHA=; h=Subject:To:References:CC:From:Message-ID:Date:MIME-Version: In-Reply-To:Content-Type; b=Bj7sARcOWsayK1X5FvIaRQ91hBO5M51Ii1nB977wUVOhOq1IF1QaSN9mTA4+K1HrylSc8WzF6xfwST540GW3JYZLOPQ8UlE8Ot/d0JUHJ+7oxSzSeLQMzZsV0nKed2I3b5DGWf/lHZ/vI5jWku75KTopb/YwS+g13ueM9GS6cY0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.187 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.48]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4TgHsh43HmzWv1j; Thu, 22 Feb 2024 10:59:04 +0800 (CST) Received: from dggpeml500002.china.huawei.com (unknown [7.185.36.158]) by mail.maildlp.com (Postfix) with ESMTPS id 07A5618005D; Thu, 22 Feb 2024 11:00:45 +0800 (CST) Received: from [10.67.120.218] (10.67.120.218) by dggpeml500002.china.huawei.com (7.185.36.158) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Thu, 22 Feb 2024 11:00:44 +0800 Subject: Re: Re: [PATCH 6/7] drivers/perf: hisi_pcie: Merge find_related_event() and get_event_idx() To: Jonathan Cameron , Yicong Yang References: <20240204074527.47110-1-yangyicong@huawei.com> <20240204074527.47110-7-yangyicong@huawei.com> <20240208123946.00006618@Huawei.com> CC: , , , , , , , From: hejunhao Message-ID: <1c14d50d-fc51-cc34-aa97-358466c19fe6@huawei.com> Date: Thu, 22 Feb 2024 11:00:44 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20240208123946.00006618@Huawei.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpeml500002.china.huawei.com (7.185.36.158) Hi, Jonathan On 2024/2/8 20:39, Jonathan Cameron wrote: > 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. Thanks for the comments, will fix in next version. > >> --- >> 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; Yes, I will do that. >> 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) Ok, will fix it. > >> + 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; Okay >> } >> >> 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; Sure. > >> >> 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); >> >