From patchwork Fri Apr 22 10:01:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Bristot de Oliveira X-Patchwork-Id: 12823174 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 15700C4332F for ; Fri, 22 Apr 2022 10:01:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1446367AbiDVKEd (ORCPT ); Fri, 22 Apr 2022 06:04:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43442 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1446354AbiDVKEc (ORCPT ); Fri, 22 Apr 2022 06:04:32 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 052D853B4E; Fri, 22 Apr 2022 03:01:40 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 959B461BCE; Fri, 22 Apr 2022 10:01:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A024C385AA; Fri, 22 Apr 2022 10:01:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1650621699; bh=axp9HX7cH7ozyam8yOtFy1KzpmCbuDnkcf64PAIPMj8=; h=From:To:Cc:Subject:Date:From; b=lp1i8A7HK35Z3HUTkFGQ0rxRAAHA6XB4dh1OCejV16WOt7HNoZzPjOqgEqtgxRlfy eJz6WJtuduEAOeEFZq9mFScEe7PZUaZvbPFjYqorKuAt/c9PLiy95ChAZpgVjfxRfu tit9ItGbfWRovD3ZH/mm0yuCoPiDt58dHNBSjEEpOaraWxXnaoZrfvmIKBYD2jkPCM 3+pRE9SuqDXgxuCF6Y6Nz3gjM6JMODye189vPlmxGJLwO/00FtkapNpvaNn5bOC5eN Dc/kJAo2if8mz7hkImM4nvBh1I/12kk3T2xdixuChTmuZoie2X41PVIuTds23Wzs84 +B8YCslEOAovg== From: Daniel Bristot de Oliveira To: Steven Rostedt , linux-trace-devel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Daniel Bristot de Oliveira , John Kacur , Daniel Wagner Subject: [PATCH 1/2] rtla: Remove procps-ng dependency Date: Fri, 22 Apr 2022 12:01:31 +0200 Message-Id: <52161d343abeda6d039d2f0734904a1383a4c62e.1650617571.git.bristot@kernel.org> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org Daniel Wagner reported to me that readproc.h got deprecated. Also, while the procps-ng library was available on Fedora, it was not available on RHEL, which is a piece of evidence that it was not that used. rtla uses procps-ng only to find the PID of the tracers' workload. I used the procps-ng library to avoid reinventing the wheel. But in this case, reinventing the wheel took me less time than the time we already took trying to work around problems. Implement a function that reads /proc/ entries, checking if: - the entry is a directory - the directory name is composed only of digits (PID) - the directory contains the comm file - the comm file contains a comm that matches the tracers' workload prefix. - then return true; otherwise, return false. And use it instead of procps-ng. Cc: John Kacur Cc: Steven Rostedt Fixes: b1696371d865 ("rtla: Helper functions for rtla") Reported-by: Daniel Wagner Signed-off-by: Daniel Bristot de Oliveira --- tools/tracing/rtla/Makefile | 2 +- tools/tracing/rtla/README.txt | 1 - tools/tracing/rtla/src/utils.c | 83 +++++++++++++++++++++++++++------- tools/tracing/rtla/src/utils.h | 1 + 4 files changed, 68 insertions(+), 19 deletions(-) diff --git a/tools/tracing/rtla/Makefile b/tools/tracing/rtla/Makefile index 11fb417abb42..90b8e20d1118 100644 --- a/tools/tracing/rtla/Makefile +++ b/tools/tracing/rtla/Makefile @@ -31,7 +31,7 @@ TRACEFS_HEADERS := $$($(PKG_CONFIG) --cflags libtracefs) CFLAGS := -O -g -DVERSION=\"$(VERSION)\" $(FOPTS) $(MOPTS) $(WOPTS) $(TRACEFS_HEADERS) LDFLAGS := -ggdb -LIBS := $$($(PKG_CONFIG) --libs libtracefs) -lprocps +LIBS := $$($(PKG_CONFIG) --libs libtracefs) SRC := $(wildcard src/*.c) HDR := $(wildcard src/*.h) diff --git a/tools/tracing/rtla/README.txt b/tools/tracing/rtla/README.txt index 6c88446f7e74..7bc0b931ddfd 100644 --- a/tools/tracing/rtla/README.txt +++ b/tools/tracing/rtla/README.txt @@ -13,7 +13,6 @@ following libraries: - libtracefs - libtraceevent - - procps It also depends on python3-docutils to compile man pages. diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c index da2b590edaed..baf9003d5d41 100644 --- a/tools/tracing/rtla/src/utils.c +++ b/tools/tracing/rtla/src/utils.c @@ -3,7 +3,7 @@ * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira */ -#include +#include #include #include #include @@ -262,6 +262,62 @@ int __set_sched_attr(int pid, struct sched_attr *attr) return 0; } + +/* + * procfs_is_workload_pid - check if a procfs entry contains a workload_prefix* comm + * + * Check if the procfs entry is a directory of a process, and then check if the + * process has a comm with the prefix set in char *workload_prefix. As the + * current users of this function only check for kernel threads, there is no + * need to check for the threads for the process. + * + * Return: True if the proc_entry contains a comm file with workload_prefix*. + * Otherwise returns false. + */ +static int procfs_is_workload_pid(const char *workload_prefix, struct dirent *proc_entry) +{ + char comm_path[MAX_PATH], comm[MAX_PATH]; + int comm_fd, retval; + char *t_name; + + if (proc_entry->d_type != DT_DIR) + return 0; + + if (*proc_entry->d_name == '.') + return 0; + + /* check if the string is a pid */ + for (t_name = proc_entry->d_name; t_name; t_name++) { + if (!isdigit(*t_name)) + break; + } + + if (*t_name != '\0') + return 0; + + snprintf(comm_path, MAX_PATH, "/proc/%s/comm", proc_entry->d_name); + comm_fd = open(comm_path, O_RDONLY); + if (comm_fd < 0) + return 0; + + memset(comm, 0, MAX_PATH); + retval = read(comm_fd, comm, MAX_PATH); + + close(comm_fd); + + if (retval <= 0) + return 0; + + retval = !strncmp(workload_prefix, comm, strlen(workload_prefix)); + if (!retval) + return 0; + + /* comm already have \n */ + debug_msg("Found workload pid:%s comm:%s", proc_entry->d_name, comm); + + return 1; +} + /* * set_comm_sched_attr - set sched params to threads starting with char *comm * @@ -272,33 +328,26 @@ int __set_sched_attr(int pid, struct sched_attr *attr) */ int set_comm_sched_attr(const char *comm, struct sched_attr *attr) { - int flags = PROC_FILLCOM | PROC_FILLSTAT; - PROCTAB *ptp; - proc_t task; + struct dirent *proc_entry; + DIR *procfs; int retval; - ptp = openproc(flags); - if (!ptp) { - err_msg("error openproc()\n"); - return -ENOENT; - } + procfs = opendir("/proc"); - memset(&task, 0, sizeof(task)); + while ((proc_entry = readdir(procfs))) { - while (readproc(ptp, &task)) { - retval = strncmp(comm, task.cmd, strlen(comm)); - if (retval) + retval = procfs_is_workload_pid(comm, proc_entry); + if (!retval) continue; - retval = __set_sched_attr(task.tid, attr); + + /* procfs_is_workload_pid confirmed it is a pid */ + retval = __set_sched_attr(atoi(proc_entry->d_name), attr); if (retval) goto out_err; } - - closeproc(ptp); return 0; out_err: - closeproc(ptp); return 1; } diff --git a/tools/tracing/rtla/src/utils.h b/tools/tracing/rtla/src/utils.h index fa08e374870a..4959a3e2c0d5 100644 --- a/tools/tracing/rtla/src/utils.h +++ b/tools/tracing/rtla/src/utils.h @@ -6,6 +6,7 @@ * '18446744073709551615\0' */ #define BUFF_U64_STR_SIZE 24 +#define MAX_PATH 1024 #define container_of(ptr, type, member)({ \ const typeof(((type *)0)->member) *__mptr = (ptr); \ From patchwork Fri Apr 22 10:01:32 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Bristot de Oliveira X-Patchwork-Id: 12823175 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 228CCC433EF for ; Fri, 22 Apr 2022 10:01:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1446378AbiDVKEi (ORCPT ); Fri, 22 Apr 2022 06:04:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1446372AbiDVKEe (ORCPT ); Fri, 22 Apr 2022 06:04:34 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E3CDB53B4E; Fri, 22 Apr 2022 03:01:41 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7E83F61E24; Fri, 22 Apr 2022 10:01:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7658AC385AB; Fri, 22 Apr 2022 10:01:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1650621700; bh=cMsSW5/kTvhMw/MKLChTukDgmLgNss7KgrlFXjRpWug=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jT+sLeV7aPn2i/iEb23mZ5FK122o8oWRYzwyyyAKYYM9tIVytcwEvCfs9w78woKys rNdXZ4whj9wUl50bcD6xWDTAKe6jU9otuM3ulTl/e/EYsvDJ92sD4AJvAoJHk/RkYZ ZCz3G/hTvDo+VKNNDD5714LMaF/Rpoq7KEHkf1SCj6bn1F/cIhPpIIeyS2gVF6/S5X 4GJtGvaVUG1/4QmKUiGNVk4urfRqibhooH/9ZzTf2Yw2mKhaEgMoj7PmDFlMNO7p3y HfCdkWg6YnPIGYglfnrbpyWTFFKEzdY6X8V8XGvaAQeEaHaLxQkUNDU5twrWxRmHeR 5fHGZtnuLWZIg== From: Daniel Bristot de Oliveira To: Steven Rostedt , linux-trace-devel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Daniel Bristot de Oliveira , John Kacur , Daniel Wagner Subject: [PATCH 2/2] rtla: Fix __set_sched_attr error message Date: Fri, 22 Apr 2022 12:01:32 +0200 Message-Id: X-Mailer: git-send-email 2.32.0 In-Reply-To: <52161d343abeda6d039d2f0734904a1383a4c62e.1650617571.git.bristot@kernel.org> References: <52161d343abeda6d039d2f0734904a1383a4c62e.1650617571.git.bristot@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org rtla's function __set_sched_attr() was borrowed from stalld, but I forgot to update the error message to something meaningful for rtla. Update the error message from: boost_with_deadline failed to boost pid PID: STRERROR to a proper one: Failed to set sched attributes to the pid PID: STRERROR Cc: Steven Rostedt Fixes: b1696371d865 ("rtla: Helper functions for rtla") Signed-off-by: Daniel Bristot de Oliveira --- tools/tracing/rtla/src/utils.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c index baf9003d5d41..60dd48315315 100644 --- a/tools/tracing/rtla/src/utils.c +++ b/tools/tracing/rtla/src/utils.c @@ -255,7 +255,7 @@ int __set_sched_attr(int pid, struct sched_attr *attr) retval = sched_setattr(pid, attr, flags); if (retval < 0) { - err_msg("boost_with_deadline failed to boost pid %d: %s\n", + err_msg("Failed to set sched attributes to the pid %d: %s\n", pid, strerror(errno)); return 1; }