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 Received: from picard.linux.it (picard.linux.it [213.254.12.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0236BC61DA4 for ; Tue, 14 Feb 2023 11:59:56 +0000 (UTC) Received: from picard.linux.it (localhost [IPv6:::1]) by picard.linux.it (Postfix) with ESMTP id 25DEA3CC608 for ; Tue, 14 Feb 2023 12:59:54 +0100 (CET) Received: from in-5.smtp.seeweb.it (in-5.smtp.seeweb.it [IPv6:2001:4b78:1:20::5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384)) (No client certificate requested) by picard.linux.it (Postfix) with ESMTPS id 8D0473CBF4A for ; Tue, 14 Feb 2023 12:59:43 +0100 (CET) Received: from Atcsqr.andestech.com (60-248-80-70.hinet-ip.hinet.net [60.248.80.70]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by in-5.smtp.seeweb.it (Postfix) with ESMTPS id 3C329600833 for ; Tue, 14 Feb 2023 12:59:40 +0100 (CET) Received: from mail.andestech.com (ATCPCS16.andestech.com [10.0.1.222]) by Atcsqr.andestech.com with ESMTP id 31EBxV98064172; Tue, 14 Feb 2023 19:59:31 +0800 (+08) (envelope-from ycliang@andestech.com) Received: from ubuntu01 (10.0.12.75) by ATCPCS16.andestech.com (10.0.1.222) with Microsoft SMTP Server id 14.3.498.0; Tue, 14 Feb 2023 19:59:30 +0800 Date: Tue, 14 Feb 2023 11:59:15 +0000 From: Leo Liang To: Cyril Hrubis Message-ID: References: <20230213134104.229241-1-ycliang@andestech.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/2.0.5 (2021-01-21) X-Originating-IP: [10.0.12.75] X-DNSRBL: X-MAIL: Atcsqr.andestech.com 31EBxV98064172 X-Virus-Scanned: clamav-milter 0.102.4 at in-5.smtp.seeweb.it X-Virus-Status: Clean Subject: Re: [LTP] [PATCH 1/1] lib/tst_pid.c: Count used pid by traversing /proc X-BeenThere: ltp@lists.linux.it X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Test Project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ltp@lists.linux.it Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ltp-bounces+ltp=archiver.kernel.org@lists.linux.it Sender: "ltp" Hi Cyril, On Tue, Feb 14, 2023 at 11:58:21AM +0100, Cyril Hrubis wrote: > Hi! > > Use "ps -eT | wc -l" to calculate the number of used pid > > could have an incorrectly larger result because "ps -eT" > > may list the same pid multiple times (with different SPID). > > > > Instead, we could count used pid by traversing /proc > > directory and count the subdirectories that have name > > composed of digits. > > > > Increase PIDS_RESERVED to avoid fork failure. > > The changes looks good, but can we please split the patch into two? > > We should keep the change to the PIDS_RESERVED separate from the code > changes. > Got it! Will send a v3 ASAP! Best regards, Leo > > Signed-off-by: Leo Yu-Chi Liang > > --- > > lib/tst_pid.c | 26 +++++++++++--------------- > > 1 file changed, 11 insertions(+), 15 deletions(-) > > > > diff --git a/lib/tst_pid.c b/lib/tst_pid.c > > index 5595e79bd..7582e4828 100644 > > --- a/lib/tst_pid.c > > +++ b/lib/tst_pid.c > > @@ -18,6 +18,7 @@ > > * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA > > */ > > > > +#include > > #include > > #include > > #include > > @@ -35,7 +36,7 @@ > > #define CGROUPS_V1_SLICE_FMT "/sys/fs/cgroup/pids/user.slice/user-%d.slice/pids.max" > > #define CGROUPS_V2_SLICE_FMT "/sys/fs/cgroup/user.slice/user-%d.slice/pids.max" > > /* Leave some available processes for the OS */ > > -#define PIDS_RESERVE 50 > > +#define PIDS_RESERVE 200 > > > > pid_t tst_get_unused_pid_(void (*cleanup_fn) (void)) > > { > > @@ -113,21 +114,16 @@ static int get_session_pids_limit(void (*cleanup_fn) (void)) > > > > int tst_get_free_pids_(void (*cleanup_fn) (void)) > > { > > - FILE *f; > > - int rc, used_pids, max_pids, max_session_pids, max_threads; > > - > > - f = popen("ps -eT | wc -l", "r"); > > - if (!f) { > > - tst_brkm(TBROK, cleanup_fn, "Could not run 'ps' to calculate used pids"); > > - return -1; > > - } > > - rc = fscanf(f, "%i", &used_pids); > > - pclose(f); > > - > > - if (rc != 1 || used_pids < 0) { > > - tst_brkm(TBROK, cleanup_fn, "Could not read output of 'ps' to calculate used pids"); > > - return -1; > > + DIR *f; > > + struct dirent *ent; > > + int max_pids, max_session_pids, max_threads, used_pids = 0; > > + > > + f = SAFE_OPENDIR("/proc"); > > + while ((ent = SAFE_READDIR(f))) { > > + if (isdigit(ent->d_name[0])) > > + ++used_pids; > > } > > + SAFE_CLOSEDIR(f); > > > > SAFE_FILE_SCANF(cleanup_fn, PID_MAX_PATH, "%d", &max_pids); > > SAFE_FILE_SCANF(cleanup_fn, THREADS_MAX_PATH, "%d", &max_threads); > > -- > > 2.34.1 > > > > > > -- > > Mailing list info: https://lists.linux.it/listinfo/ltp > > -- > Cyril Hrubis > chrubis@suse.cz -- Mailing list info: https://lists.linux.it/listinfo/ltp