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=-9.6 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,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 19DCFC33C8C for ; Thu, 28 Nov 2019 08:54:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA35E21775 for ; Thu, 28 Nov 2019 08:54:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Ut4ueYVS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727198AbfK1IyW (ORCPT ); Thu, 28 Nov 2019 03:54:22 -0500 Received: from mail-lj1-f194.google.com ([209.85.208.194]:36389 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726764AbfK1IyW (ORCPT ); Thu, 28 Nov 2019 03:54:22 -0500 Received: by mail-lj1-f194.google.com with SMTP id k15so27610935lja.3 for ; Thu, 28 Nov 2019 00:54:21 -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=1vr5+JkKcuoZVsjx/XbK96E0u7JOyC3v723be9HMndo=; b=Ut4ueYVSL9ggCIgvgBIJyp/Ud3BAZsB/GY4A9KhQRrm8PuL4Z+AyOYlNKh5ptHSlaV g3cU6pQVi79MRVo3ccwa2POEICoBT3vpMDl2ZB2Gr4QYkQQq82RknQK6V0G2evwX3+UQ tCBfoIm5vxXTi5xxxG/XvyUmXhyFjQcSzqjRc41XzDgBmSelSo3gV6kNSIa+rMLny8B9 q1shAkFZwYkMRAjAdNWhNxtqNvRiajPBDq5Qz38n7ZMJK7Q9TMbj7lW8JE9qKqv5vevf 183SDj5UC+jPtYYvLqd0JNr684uG8deduMByFLQq8RDR0E0T+3HzaChNg95qk/xbZVfh jO0A== 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=1vr5+JkKcuoZVsjx/XbK96E0u7JOyC3v723be9HMndo=; b=IZEzGdlOwzEEm0t1TCkUbcKqmgrYtpt+v72TxqibvpAtyfcInD0VyRxEoc5CcS+4AZ 0UF34CxdAWQo/MIxFf4FnUO69pKZ+yU9vvb23A+yG4jgD/Xmq9iD+4wOVJnEDk+veGkU InQIkhZR0hsXiki/vIgaYg7ioHpYKdvsS+4S1CYtaelvWRp3IG3qOfbdrEBZ1v4rm9rk jl4k6M4FzBM8X+/+MaU64eD4+HsTPhOhswhn45qfVA7Ztc2lhqjeqBBWJucttwqJQ68c mr2X9UhB5s4bfFn/cqK2UPL9tuepQp2p+/vogE/NQLVwoQeq55uuxfycJyz6fd9Jyw1e AVvw== X-Gm-Message-State: APjAAAWe9BwrmkUapxIOqeDTOPFUepmyXg2ju05rTHP2nxwCxQfbA54m DYkx26ilaQS69fyigDlzxcg= X-Google-Smtp-Source: APXvYqxOgyKCCtvfethG1kFHROTFQeBSsR6Al/TjI9GxwzMsP2qbgkRpxyftKIePnLAgeCv+Q+Hg/w== X-Received: by 2002:a2e:9ac4:: with SMTP id p4mr3392431ljj.207.1574931260533; Thu, 28 Nov 2019 00:54:20 -0800 (PST) Received: from oberon.eng.vmware.com ([146.247.46.5]) by smtp.gmail.com with ESMTPSA id z19sm8253735ljk.66.2019.11.28.00.54.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Nov 2019 00:54:19 -0800 (PST) From: "Tzvetomir Stoyanov (VMware)" To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH v15 07/18] trace-cmd: Find and store pids of tasks, which run virtual CPUs of given VM Date: Thu, 28 Nov 2019 10:53:58 +0200 Message-Id: <20191128085409.289684-8-tz.stoyanov@gmail.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191128085409.289684-1-tz.stoyanov@gmail.com> References: <20191128085409.289684-1-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 | 57 ++++++++++++++++++++++++++++++++++ 2 files changed, 59 insertions(+) diff --git a/tracecmd/include/trace-local.h b/tracecmd/include/trace-local.h index a51f0d0..51abef1 100644 --- a/tracecmd/include/trace-local.h +++ b/tracecmd/include/trace-local.h @@ -243,6 +243,8 @@ 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 4459c90..fd7ca82 100644 --- a/tracecmd/trace-record.c +++ b/tracecmd/trace-record.c @@ -2873,10 +2873,12 @@ 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; @@ -2894,6 +2896,46 @@ 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) + goto next; + if (strncmp(buf, "CPU ", 4) != 0) + goto next; + + vcpu = atoi(buf+4); + if (!(vcpu >= 0 && vcpu < VCPUS_MAX)) + goto next; + guest->cpu_pid[vcpu] = atoi(entry->d_name); + +next: + fclose(f); + } + free(buf); +} + static void read_qemu_guests(void) { static bool initialized; @@ -2957,6 +2999,8 @@ 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"); @@ -3002,6 +3046,19 @@ 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; -- 2.23.0