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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 233E8C4CECE for ; Fri, 13 Mar 2020 18:34:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 009CB20749 for ; Fri, 13 Mar 2020 18:34:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727240AbgCMSe3 (ORCPT ); Fri, 13 Mar 2020 14:34:29 -0400 Received: from mga06.intel.com ([134.134.136.31]:28623 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726620AbgCMSe3 (ORCPT ); Fri, 13 Mar 2020 14:34:29 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Mar 2020 11:34:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,549,1574150400"; d="scan'208";a="442506055" Received: from labuser-ice-lake-client-platform.jf.intel.com ([10.54.55.45]) by fmsmga005.fm.intel.com with ESMTP; 13 Mar 2020 11:34:28 -0700 From: kan.liang@linux.intel.com To: acme@kernel.org, jolsa@redhat.com, peterz@infradead.org, mingo@redhat.com, linux-kernel@vger.kernel.org Cc: namhyung@kernel.org, adrian.hunter@intel.com, mathieu.poirier@linaro.org, ravi.bangoria@linux.ibm.com, alexey.budankov@linux.intel.com, vitaly.slobodskoy@intel.com, pavel.gerasimov@intel.com, mpe@ellerman.id.au, eranian@google.com, ak@linux.intel.com, Kan Liang Subject: [PATCH V3 01/17] perf pmu: Add support for PMU capabilities Date: Fri, 13 Mar 2020 11:33:03 -0700 Message-Id: <20200313183319.17739-2-kan.liang@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200313183319.17739-1-kan.liang@linux.intel.com> References: <20200313183319.17739-1-kan.liang@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kan Liang The PMU capabilities information, which is located at /sys/bus/event_source/devices//caps, is required by perf tool. For example, the max LBR information is required to stitch LBR call stack. Add perf_pmu__caps_parse() to parse the PMU capabilities information. The information is stored in a list. Add perf_pmu__scan_caps() to scan the capabilities one by one. The following patch will store the capabilities information in perf header. Reviewed-by: Andi Kleen Signed-off-by: Kan Liang --- tools/perf/util/pmu.c | 98 +++++++++++++++++++++++++++++++++++++++++++ tools/perf/util/pmu.h | 12 ++++++ 2 files changed, 110 insertions(+) diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c index 8b99fd312aae..4cdfbb669567 100644 --- a/tools/perf/util/pmu.c +++ b/tools/perf/util/pmu.c @@ -844,6 +844,7 @@ static struct perf_pmu *pmu_lookup(const char *name) INIT_LIST_HEAD(&pmu->format); INIT_LIST_HEAD(&pmu->aliases); + INIT_LIST_HEAD(&pmu->caps); list_splice(&format, &pmu->format); list_splice(&aliases, &pmu->aliases); list_add_tail(&pmu->list, &pmus); @@ -1565,3 +1566,100 @@ int perf_pmu__scan_file(struct perf_pmu *pmu, const char *name, const char *fmt, va_end(args); return ret; } + +static int perf_pmu__new_caps(struct list_head *list, char *name, char *value) +{ + struct perf_pmu_caps *caps; + + caps = zalloc(sizeof(*caps)); + if (!caps) + return -ENOMEM; + + caps->name = strdup(name); + if (!caps->name) + goto free_caps; + caps->value = strndup(value, strlen(value) - 1); + if (!caps->value) + goto free_name; + list_add_tail(&caps->list, list); + return 0; + +free_name: + free(caps->name); +free_caps: + free(caps); + + return -ENOMEM; +} + +/* + * Reading/parsing the given pmu capabilities, which should be located at: + * /sys/bus/event_source/devices//caps as sysfs group attributes. + * Return the number of capabilities + */ +int perf_pmu__caps_parse(struct perf_pmu *pmu) +{ + struct stat st; + char caps_path[PATH_MAX]; + const char *sysfs = sysfs__mountpoint(); + DIR *caps_dir; + struct dirent *evt_ent; + int nr_caps = 0; + + if (!sysfs) + return -1; + + snprintf(caps_path, PATH_MAX, + "%s" EVENT_SOURCE_DEVICE_PATH "%s/caps", sysfs, pmu->name); + + if (stat(caps_path, &st) < 0) + return 0; /* no error if caps does not exist */ + + caps_dir = opendir(caps_path); + if (!caps_dir) + return -EINVAL; + + while ((evt_ent = readdir(caps_dir)) != NULL) { + char path[PATH_MAX + NAME_MAX + 1]; + char *name = evt_ent->d_name; + char value[128]; + FILE *file; + + if (!strcmp(name, ".") || !strcmp(name, "..")) + continue; + + snprintf(path, sizeof(path), "%s/%s", caps_path, name); + + file = fopen(path, "r"); + if (!file) + break; + + if (!fgets(value, sizeof(value), file) || + (perf_pmu__new_caps(&pmu->caps, name, value) < 0)) { + fclose(file); + break; + } + + nr_caps++; + fclose(file); + } + + closedir(caps_dir); + + return nr_caps; +} + +struct perf_pmu_caps *perf_pmu__scan_caps(struct perf_pmu *pmu, + struct perf_pmu_caps *caps) +{ + if (!pmu) + return NULL; + + if (!caps) + caps = list_prepare_entry(caps, &pmu->caps, list); + + list_for_each_entry_continue(caps, &pmu->caps, list) + return caps; + + return NULL; +} diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h index 6737e3d5d568..a228e27ae462 100644 --- a/tools/perf/util/pmu.h +++ b/tools/perf/util/pmu.h @@ -21,6 +21,12 @@ enum { struct perf_event_attr; +struct perf_pmu_caps { + char *name; + char *value; + struct list_head list; +}; + struct perf_pmu { char *name; __u32 type; @@ -32,6 +38,7 @@ struct perf_pmu { struct perf_cpu_map *cpus; struct list_head format; /* HEAD struct perf_pmu_format -> list */ struct list_head aliases; /* HEAD struct perf_pmu_alias -> list */ + struct list_head caps; /* HEAD struct perf_pmu_caps -> list */ struct list_head list; /* ELEM */ }; @@ -102,4 +109,9 @@ struct pmu_events_map *perf_pmu__find_map(struct perf_pmu *pmu); int perf_pmu__convert_scale(const char *scale, char **end, double *sval); +int perf_pmu__caps_parse(struct perf_pmu *pmu); + +struct perf_pmu_caps *perf_pmu__scan_caps(struct perf_pmu *pmu, + struct perf_pmu_caps *caps); + #endif /* __PMU_H */ -- 2.17.1