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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45843C4167B for ; Tue, 14 Dec 2021 16:57:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236235AbhLNQ44 (ORCPT ); Tue, 14 Dec 2021 11:56:56 -0500 Received: from mx0a-0016f401.pphosted.com ([67.231.148.174]:52166 "EHLO mx0b-0016f401.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S236165AbhLNQ4o (ORCPT ); Tue, 14 Dec 2021 11:56:44 -0500 Received: from pps.filterd (m0045849.ppops.net [127.0.0.1]) by mx0a-0016f401.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 1BE8O7CW008362; Tue, 14 Dec 2021 08:56:35 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=marvell.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=pfpt0220; bh=s6/s0ur6IyX5neF4XjjckuSdNjMDRLoVnW1ZfvV0mZ0=; b=SuoOW4Do2q4lrB1rTiRU3VuSEn7l2t3+xPN7CBMsA8+sRvddDX8kMT1yrbIpcdkuVU0h 2bDXcjMNOZbCOVqJq7ppJOZIWfSkfZzuNaI5378ldKTDgHGzxPGUMwbWZUZrFpl2hdtb ona0h8JAUDZbAW1HlGmlT5lNnpQIK/aziruK1gWWY5PubfzWSkjP1U9/FMkFiiH/9HVX SM0XCtcmp5EU0USfHGK+xTEhSg0y3XLWxTHX9rl9fpnLSFXxD+FOxD8x0tyhuSNhiHRc QROUEDt91ciagLr3u7FwAwupJtenYDB/yJNhFOpZLXkwYugsEu1/7Vu/Cvq+Hw7AAyu+ TA== Received: from dc5-exch02.marvell.com ([199.233.59.182]) by mx0a-0016f401.pphosted.com (PPS) with ESMTPS id 3cxqqsj43p-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Tue, 14 Dec 2021 08:56:35 -0800 Received: from DC5-EXCH01.marvell.com (10.69.176.38) by DC5-EXCH02.marvell.com (10.69.176.39) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Tue, 14 Dec 2021 08:56:34 -0800 Received: from bbhushan2.marvell.com (10.69.176.80) by DC5-EXCH01.marvell.com (10.69.176.38) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 14 Dec 2021 08:56:31 -0800 From: Bharat Bhushan To: , , , , , , , CC: Bharat Bhushan Subject: [PATCH v7 3/4] perf/marvell: cn10k DDR perfmon event overflow handling Date: Tue, 14 Dec 2021 22:26:12 +0530 Message-ID: <20211214165613.26479-4-bbhushan2@marvell.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211214165613.26479-1-bbhushan2@marvell.com> References: <20211214165613.26479-1-bbhushan2@marvell.com> MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-GUID: ue_LOMAcv88d7LmvbGqa9SafN_8LLb2P X-Proofpoint-ORIG-GUID: ue_LOMAcv88d7LmvbGqa9SafN_8LLb2P X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2021-12-14_07,2021-12-14_01,2021-12-02_01 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org CN10k DSS h/w perfmon does not support event overflow interrupt, so periodic timer is being used. Each event counter is 48bit, which in worst case scenario can increment at maximum 5.6 GT/s. At this rate it may take many hours to overflow these counters. Therefore polling period for overflow is set to 100 sec, which can be changed using sysfs parameter. Two fixed event counters starts counting from zero on overflow, so overflow condition is when new count less than previous count. While eight programmable event counters freezes at maximum value. Also individual counter cannot be restarted, so need to restart all eight counters. Signed-off-by: Bharat Bhushan Reviewed-by: Bhaskara Budiredla --- v3->v7 - No Change v2->v3: - uintXX_t -> uXX v1->v2: - No Change drivers/perf/marvell_cn10k_ddr_pmu.c | 111 +++++++++++++++++++++++++++ 1 file changed, 111 insertions(+) diff --git a/drivers/perf/marvell_cn10k_ddr_pmu.c b/drivers/perf/marvell_cn10k_ddr_pmu.c index 9b6d5e716b94..21fccb9090c5 100644 --- a/drivers/perf/marvell_cn10k_ddr_pmu.c +++ b/drivers/perf/marvell_cn10k_ddr_pmu.c @@ -11,6 +11,7 @@ #include #include #include +#include /* Performance Counters Operating Mode Control Registers */ #define DDRC_PERF_CNT_OP_MODE_CTRL 0x8020 @@ -127,6 +128,7 @@ struct cn10k_ddr_pmu { struct device *dev; int active_events; struct perf_event *events[DDRC_PERF_NUM_COUNTERS]; + struct hrtimer hrtimer; }; #define to_cn10k_ddr_pmu(p) container_of(p, struct cn10k_ddr_pmu, pmu) @@ -251,6 +253,18 @@ static const struct attribute_group *cn10k_attr_groups[] = { NULL, }; +/* Default poll timeout is 100 sec, which is very sufficient for + * 48 bit counter incremented max at 5.6 GT/s, which may take many + * hours to overflow. + */ +static unsigned long cn10k_ddr_pmu_poll_period_sec = 100; +module_param_named(poll_period_sec, cn10k_ddr_pmu_poll_period_sec, ulong, 0644); + +static ktime_t cn10k_ddr_pmu_timer_period(void) +{ + return ms_to_ktime((u64)cn10k_ddr_pmu_poll_period_sec * USEC_PER_SEC); +} + static int ddr_perf_get_event_bitmap(int eventid, u64 *event_bitmap) { switch (eventid) { @@ -433,6 +447,10 @@ static int cn10k_ddr_perf_event_add(struct perf_event *event, int flags) pmu->active_events++; hwc->idx = counter; + if (pmu->active_events == 1) + hrtimer_start(&pmu->hrtimer, cn10k_ddr_pmu_timer_period(), + HRTIMER_MODE_REL_PINNED); + if (counter < DDRC_PERF_NUM_GEN_COUNTERS) { /* Generic counters, configure event id */ reg_offset = DDRC_PERF_CFG(counter); @@ -484,6 +502,10 @@ static void cn10k_ddr_perf_event_del(struct perf_event *event, int flags) cn10k_ddr_perf_free_counter(pmu, counter); pmu->active_events--; hwc->idx = -1; + + /* Cancel timer when no events to capture */ + if (pmu->active_events == 0) + hrtimer_cancel(&pmu->hrtimer); } static void cn10k_ddr_perf_pmu_enable(struct pmu *pmu) @@ -502,6 +524,92 @@ static void cn10k_ddr_perf_pmu_disable(struct pmu *pmu) DDRC_PERF_CNT_END_OP_CTRL); } +static void cn10k_ddr_perf_event_update_all(struct cn10k_ddr_pmu *pmu) +{ + struct hw_perf_event *hwc; + int i; + + for (i = 0; i < DDRC_PERF_NUM_GEN_COUNTERS; i++) { + if (pmu->events[i] == NULL) + continue; + + cn10k_ddr_perf_event_update(pmu->events[i]); + } + + /* Reset previous count as h/w counter are reset */ + for (i = 0; i < DDRC_PERF_NUM_GEN_COUNTERS; i++) { + if (pmu->events[i] == NULL) + continue; + + hwc = &pmu->events[i]->hw; + local64_set(&hwc->prev_count, 0); + } +} + +static irqreturn_t cn10k_ddr_pmu_overflow_handler(struct cn10k_ddr_pmu *pmu) +{ + struct perf_event *event; + struct hw_perf_event *hwc; + u64 prev_count, new_count; + u64 value; + int i; + + event = pmu->events[DDRC_PERF_READ_COUNTER_IDX]; + if (event) { + hwc = &event->hw; + prev_count = local64_read(&hwc->prev_count); + new_count = cn10k_ddr_perf_read_counter(pmu, hwc->idx); + + /* Overflow condition is when new count less than + * previous count + */ + if (new_count < prev_count) + cn10k_ddr_perf_event_update(event); + } + + event = pmu->events[DDRC_PERF_WRITE_COUNTER_IDX]; + if (event) { + hwc = &event->hw; + prev_count = local64_read(&hwc->prev_count); + new_count = cn10k_ddr_perf_read_counter(pmu, hwc->idx); + + /* Overflow condition is when new count less than + * previous count + */ + if (new_count < prev_count) + cn10k_ddr_perf_event_update(event); + } + + for (i = 0; i < DDRC_PERF_NUM_GEN_COUNTERS; i++) { + if (pmu->events[i] == NULL) + continue; + + value = cn10k_ddr_perf_read_counter(pmu, i); + if (value == DDRC_PERF_CNT_MAX_VALUE) { + pr_info("Counter-(%d) reached max value\n", i); + cn10k_ddr_perf_event_update_all(pmu); + cn10k_ddr_perf_pmu_disable(&pmu->pmu); + cn10k_ddr_perf_pmu_enable(&pmu->pmu); + } + } + + return IRQ_HANDLED; +} + +static enum hrtimer_restart cn10k_ddr_pmu_timer_handler(struct hrtimer *hrtimer) +{ + struct cn10k_ddr_pmu *pmu = container_of(hrtimer, struct cn10k_ddr_pmu, + hrtimer); + unsigned long flags; + + local_irq_save(flags); + cn10k_ddr_pmu_overflow_handler(pmu); + local_irq_restore(flags); + + hrtimer_forward_now(hrtimer, cn10k_ddr_pmu_timer_period()); + return HRTIMER_RESTART; +} + static int cn10k_ddr_perf_probe(struct platform_device *pdev) { struct cn10k_ddr_pmu *ddr_pmu; @@ -550,6 +658,9 @@ static int cn10k_ddr_perf_probe(struct platform_device *pdev) if (!name) return -ENOMEM; + hrtimer_init(&ddr_pmu->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + ddr_pmu->hrtimer.function = cn10k_ddr_pmu_timer_handler; + ret = perf_pmu_register(&ddr_pmu->pmu, name, -1); if (ret) return ret; -- 2.17.1