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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY,URIBL_BLOCKED,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 953FEC35240 for ; Fri, 31 Jan 2020 12:11:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A08F20705 for ; Fri, 31 Jan 2020 12:11:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ueYrlQ3Z" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728501AbgAaMLW (ORCPT ); Fri, 31 Jan 2020 07:11:22 -0500 Received: from mail-lj1-f194.google.com ([209.85.208.194]:44406 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728480AbgAaMLW (ORCPT ); Fri, 31 Jan 2020 07:11:22 -0500 Received: by mail-lj1-f194.google.com with SMTP id q8so6816730ljj.11 for ; Fri, 31 Jan 2020 04:11:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=lIODTiDkEXxOrAfvI1pJ6/Jb21UP2TAO6H6IWlIM9AE=; b=ueYrlQ3Zb/l2VMUm5gv+LUbVoLpOxMVsD92W/oD1oIKxEcIaUBVFbJyBE6cAIVIJJ4 kWXUUD8AU1JBcGk3J5cER+Z6nWdYYDnOkdUx/qrztSVXAnwB8cojbaBW0yoY+c5V0mQC uvCb9WEgD8OSdrpQB2PLh/5zlgdb13slMsto+TaAZU/RQ9WMemkjEhhSs9M/w29PttiO SaDMUQuNXuDldkllJMsFJymn3/JKpzXtuQKLjpf0iIlj2rltNXPnhoLhL7rIva8pflco bKm6tyzUkLhhbEoMQzUrBCi5Z2n943oX4lSMA/g9qZAT351PoG898FfdTsvDhUcLglje oCCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=lIODTiDkEXxOrAfvI1pJ6/Jb21UP2TAO6H6IWlIM9AE=; b=ZUBdijuHlOYTjNmEK9y4mMaph7TjHY8lx4PNsJ+7Dr05sxmBKyzgI9Du+5mVfqfGpt qznAfcz9eqmtN8Ue4NdEzERd8ERHVkefmAFZv+k9zzNtznYV4ET0l1NOcP6Xq8Fv2OlW L1uyRhn0pqYEwkEBcUAmBnE3LiDc5LTot1TYM8zGnsupTBjAeVT/ewGyBw6FNrXx37gW v3eQOprHY2roOFIdEpw3k/9fcspSjC5ppKVdnOoZFfJfGlJZI4CkD/1RX8zB4+8r4Q1+ ufIm4GgB6kL0DhpvzLX4yG3ahBTlkvs4gSPKP9kk4uRV68Qdp9X3F0UNiNnp/y5fUxu+ 6Xzw== X-Gm-Message-State: APjAAAVwYby5RiGyQawiBL+uNqQnQQOg/jms/rzWTaSz4xq3Y33v3Tgc EW4X11aFIiuWQgiUjHRe9Ko= X-Google-Smtp-Source: APXvYqxnW6ZRBJBTRx2XB8aC9tjLmovk/UCZcvtwIDF/2Mw3nW2LxxJ8ijih4T5AjvcrGKpjgcv3yw== X-Received: by 2002:a2e:9b05:: with SMTP id u5mr5791569lji.59.1580472678800; Fri, 31 Jan 2020 04:11:18 -0800 (PST) Received: from oberon.zico.biz ([83.222.187.186]) by smtp.gmail.com with ESMTPSA id i19sm4559965lfj.17.2020.01.31.04.11.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 31 Jan 2020 04:11:18 -0800 (PST) From: "Tzvetomir Stoyanov (VMware)" To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH v19 03/15] trace-cmd: Find and store pids of tasks, which run virtual CPUs of given VM Date: Fri, 31 Jan 2020 14:10:59 +0200 Message-Id: <20200131121111.130355-4-tz.stoyanov@gmail.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200131121111.130355-1-tz.stoyanov@gmail.com> References: <20200131121111.130355-1-tz.stoyanov@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org From: Tzvetomir Stoyanov In order to match host and guest events, a mapping between guest VCPU and the host task, running this VCPU is needed. Extended existing struct guest to hold such mapping and added logic in read_qemu_guests() function to initialize it. Implemented a new internal API, get_guest_vcpu_pid(), to retrieve VCPU-task mapping for given VM. Signed-off-by: Tzvetomir Stoyanov --- tracecmd/include/trace-local.h | 2 ++ tracecmd/trace-record.c | 54 ++++++++++++++++++++++++++++++++++ 2 files changed, 56 insertions(+) diff --git a/tracecmd/include/trace-local.h b/tracecmd/include/trace-local.h index 29f2779..a5cf064 100644 --- a/tracecmd/include/trace-local.h +++ b/tracecmd/include/trace-local.h @@ -247,6 +247,8 @@ void update_first_instance(struct buffer_instance *instance, int topt); void show_instance_file(struct buffer_instance *instance, const char *name); +int get_guest_vcpu_pid(unsigned int guest_cid, unsigned int guest_vcpu); + /* moved from trace-cmd.h */ void tracecmd_create_top_instance(char *name); void tracecmd_remove_instances(void); diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c index 28fe31b..b479e91 100644 --- a/tracecmd/trace-record.c +++ b/tracecmd/trace-record.c @@ -3031,10 +3031,12 @@ static bool is_digits(const char *s) return true; } +#define VCPUS_MAX 256 struct guest { char *name; int cid; int pid; + int cpu_pid[VCPUS_MAX]; }; static struct guest *guests; @@ -3052,6 +3054,43 @@ static char *get_qemu_guest_name(char *arg) return arg; } +static void read_qemu_guests_pids(char *guest_task, struct guest *guest) +{ + struct dirent *entry; + char path[PATH_MAX]; + char *buf = NULL; + size_t n = 0; + int vcpu; + DIR *dir; + FILE *f; + + snprintf(path, sizeof(path), "/proc/%s/task", guest_task); + dir = opendir(path); + if (!dir) + return; + + while ((entry = readdir(dir))) { + if (!(entry->d_type == DT_DIR && is_digits(entry->d_name))) + continue; + + snprintf(path, sizeof(path), "/proc/%s/task/%s/comm", + guest_task, entry->d_name); + f = fopen(path, "r"); + if (!f) + continue; + + if (getline(&buf, &n, f) >= 0 && + strncmp(buf, "CPU ", 4) == 0) { + vcpu = atoi(buf + 4); + if (vcpu >= 0 && vcpu < VCPUS_MAX) + guest->cpu_pid[vcpu] = atoi(entry->d_name); + } + + fclose(f); + } + free(buf); +} + static void read_qemu_guests(void) { static bool initialized; @@ -3115,6 +3154,8 @@ static void read_qemu_guests(void) if (!is_qemu) goto next; + read_qemu_guests_pids(entry->d_name, &guest); + guests = realloc(guests, (guests_len + 1) * sizeof(*guests)); if (!guests) die("Can not allocate guest buffer"); @@ -3160,6 +3201,19 @@ static char *parse_guest_name(char *guest, int *cid, int *port) return guest; } +int get_guest_vcpu_pid(unsigned int guest_cid, unsigned int guest_vcpu) +{ + int i; + + if (!guests || guest_vcpu >= VCPUS_MAX) + return -1; + + for (i = 0; i < guests_len; i++) + if (guest_cid == guests[i].cid) + return guests[i].cpu_pid[guest_vcpu]; + return -1; +} + static void set_prio(int prio) { struct sched_param sp; -- 2.24.1