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=-20.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 E3F20C433FE for ; Tue, 21 Sep 2021 06:05:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C81BD610A0 for ; Tue, 21 Sep 2021 06:05:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229833AbhIUGG1 (ORCPT ); Tue, 21 Sep 2021 02:06:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34074 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229619AbhIUGG0 (ORCPT ); Tue, 21 Sep 2021 02:06:26 -0400 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6A5CC061574; Mon, 20 Sep 2021 23:04:58 -0700 (PDT) Received: by mail-pj1-x102a.google.com with SMTP id z14-20020a17090a8b8e00b0019cc29ceef1so1203252pjn.1; Mon, 20 Sep 2021 23:04:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id; bh=0hrfuautjSsu8HUc15tPzwvjHVHf8IlFa6RtMmxHcxg=; b=B87f0IjTgIWrI7BwdLPIHCMDroen2ZoCFphLEUY+X/fWIeTS37v17v43kHEM4amJ2h Z0AMLODiBWJYvZ6S9//TwLJYtIfRBAEfUbIs5VQos46Pepmxltg6Bom1EfLO2zuIXAoz 3nvNiKFNYhX/F7jL/hciS0TvwTZbfNGCmxe5Nmg+gS+xNj8OhkNtrR7stHlBy/aOkhol Z+vL5jKk4Rg3IdKDIsfRKu0JmJGoOzMBnhlhDT3Ox6E/Lxy1tP8Ys58fGu0f0BtkSt2T BQTSHtNOCDSSIMOHCnmMqf3iTyd3HJfx9CUnXAOP9VyUel9P/WPh/IGlxVRzJkY6dPKf q6CQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=0hrfuautjSsu8HUc15tPzwvjHVHf8IlFa6RtMmxHcxg=; b=Mf/PUGQe6wkibqt06j3hBDDl8KSxtAPc8J54hKcYNF8RH7n1pv1OYdvX69/MTRJj71 pJAOkAE58j9Uh+uzLtWjY7FLAbeH9YfplOE5JJjhyWh88iiElTgz0KN8j+oDtLksH6Ip oq6Kb99v6uX8gOgn8Ux8z1vmW0n5XqSr09pgLgt11KZmtnHX7gy1/sn0zMugFUvqmFnB /tLd7CpprCWd5rIbIjCkij7tstfQAjKjMgbJNucUuSGozlXZBZSV7aSWqTfFDP8DbxYy JxC5xFRCnz72m1p+GUMTrQM5tJKera61EM9N08Ca/BQGyhhZv004T+aZ9O3bdwiEDoRW Dr3Q== X-Gm-Message-State: AOAM5315WCVBBekpqm3PrEhK5zKrDmpN/A7poi5AjiUKSjYZ4+97TOMi 8KiyrKBR3V1VK4CxrnDxK1U= X-Google-Smtp-Source: ABdhPJywZ1P6K5VK1vI4W8ivYf1n1wIa89I/qc3dh/evhIm5dgAPcFTveEqrUztxAH0Xv2JFjHbfsw== X-Received: by 2002:a17:902:f703:b029:12c:982:c9ae with SMTP id h3-20020a170902f703b029012c0982c9aemr26103779plo.20.1632204298152; Mon, 20 Sep 2021 23:04:58 -0700 (PDT) Received: from u18.mshome.net ([167.220.238.132]) by smtp.gmail.com with ESMTPSA id x8sm15725900pfm.8.2021.09.20.23.04.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Sep 2021 23:04:57 -0700 (PDT) From: Muhammad Falak R Wani To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, Muhammad Falak R Wani Subject: [PATCH] libbpf: Use sysconf to simplify libbpf_num_possible_cpus Date: Tue, 21 Sep 2021 11:34:34 +0530 Message-Id: <20210921060434.26732-1-falakreyaz@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Simplify libbpf_num_possible_cpus by using sysconf(_SC_NPROCESSORS_CONF) instead of parsing a file. This patch is a part of libbpf-1.0 milestone. Reference: https://github.com/libbpf/libbpf/issue/383 Signed-off-by: Muhammad Falak R Wani --- tools/lib/bpf/libbpf.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index da65a1666a5e..1d730b08ee44 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -10765,25 +10765,15 @@ int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz) int libbpf_num_possible_cpus(void) { - static const char *fcpu = "/sys/devices/system/cpu/possible"; static int cpus; - int err, n, i, tmp_cpus; - bool *mask; + int tmp_cpus; tmp_cpus = READ_ONCE(cpus); if (tmp_cpus > 0) return tmp_cpus; - err = parse_cpu_mask_file(fcpu, &mask, &n); - if (err) - return libbpf_err(err); - - tmp_cpus = 0; - for (i = 0; i < n; i++) { - if (mask[i]) - tmp_cpus++; - } - free(mask); + tmp_cpus = sysconf(_SC_NPROCESSORS_CONF); + /* sysconf sets errno; no need to use libbpf_err */ WRITE_ONCE(cpus, tmp_cpus); return tmp_cpus; -- 2.17.1