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,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 9D945C32771 for ; Mon, 13 Jan 2020 03:23:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6FB28206D6 for ; Mon, 13 Jan 2020 03:23:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="C9QgZEWv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733196AbgAMDXT (ORCPT ); Sun, 12 Jan 2020 22:23:19 -0500 Received: from mail-pj1-f66.google.com ([209.85.216.66]:36822 "EHLO mail-pj1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733020AbgAMDXT (ORCPT ); Sun, 12 Jan 2020 22:23:19 -0500 Received: by mail-pj1-f66.google.com with SMTP id n59so3650540pjb.1 for ; Sun, 12 Jan 2020 19:23:18 -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; bh=tuL/sUzlzZyNW35DUcDDiOxQ2sElchyKRZIw9ifc/VM=; b=C9QgZEWvcMn2jqlpJ+FWjpvALoeVJL2WLA7ZhF22RqsitJeARvwXpUNPpqx9Utbo2F +PLqRD+rxDA1j815sPkf+cG7P0QCpjx0Qiy1SCBfiRK+7wlo/1ULx3foHquOLXUgEnC9 67yxkR7lNRtKUAJa6ELpGTR1vI04Ba/Kdcwt9QTP2B3V/fN7hgiMy6v+S+Tts7vmwXih GShCaADo+QLDcyyiHo4M8++zKlO/6MlpAVWWzYJN43Mg8Q4tB4YJT1i3tUliQ3pUyZnE jz/jRa9PN7wPy23RtDPrBauxe3uUp8FxmTwVUm5St1KhqolJLsquh98yBO3Gkaaibl9H 8zlQ== 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; bh=tuL/sUzlzZyNW35DUcDDiOxQ2sElchyKRZIw9ifc/VM=; b=lnMVKzTNS0eEbcZD94/bZrS4lwyb2R0Wm1gb0H4/g8kqmcfVeJp9vFQYkK6y3fTuXQ Yo4WliQnGfYUvV7sLvxiEMeeqAJ0tNpPHXJNJuVEpLrwASYDZEa8TT/prPkB3kgFXcJm 67Fwlyb5UGca18ngA/WxXTszsct677cGUHv1Sxski53mQ90rti/6zuOez1HRcIiABJrU KW4q0gl9k0favIA2qSeS7B+FH514zRsnc1PKQZIp1A3KX+gZ8dG1bELkgp16XlWOiY0k Eh80frQXYcpmysmNscHOdlgQFt1iClYQaVhy1XI+RjZaXzlvv5l+7ec6SEsPMXhq7TPW fdRA== X-Gm-Message-State: APjAAAVm+fiQwL6RDto6DL7voobOD1vAcb8R25gS+lQxn3LIZdU6T3C5 U7eFrw85Bve9zOYPc2hx6JVus1kx788= X-Google-Smtp-Source: APXvYqxNwAQaG6At2rkySC52oLtC5VBQCeBbKacI3QcfkT37afSx+1J+ZsJbnaepWABFXrTfvZogvw== X-Received: by 2002:a17:902:26a:: with SMTP id 97mr11701262plc.74.1578885798230; Sun, 12 Jan 2020 19:23:18 -0800 (PST) Received: from localhost ([43.224.245.179]) by smtp.gmail.com with ESMTPSA id s131sm12638203pfs.135.2020.01.12.19.23.17 (version=TLS1_2 cipher=AES128-SHA bits=128/128); Sun, 12 Jan 2020 19:23:17 -0800 (PST) From: qiwuchen55@gmail.com To: christian.brauner@ubuntu.com, peterz@infradead.org, mingo@kernel.org, tglx@linutronix.de, oleg@redhat.com, elena.reshetova@intel.com, jgg@ziepe.ca, christian@kellner.me, aarcange@redhat.com, viro@zeniv.linux.org.uk, cyphar@cyphar.com, ldv@altlinux.org Cc: linux-kernel@vger.kernel.org, chenqiwu Subject: [PATCH] kernel/fork: put some fork variables into read-mostly section Date: Mon, 13 Jan 2020 11:23:13 +0800 Message-Id: <1578885793-24095-1-git-send-email-qiwuchen55@gmail.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: chenqiwu Since total_forks/nr_threads/max_threads global variables are frequently used for process fork, putting these variables into read_mostly section can avoid unnecessary cache line bouncing. Signed-off-by: chenqiwu --- kernel/fork.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index 0808095..163e152 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -120,10 +120,10 @@ /* * Protected counters by write_lock_irq(&tasklist_lock) */ -unsigned long total_forks; /* Handle normal Linux uptimes. */ -int nr_threads; /* The idle threads do not count.. */ +unsigned long total_forks __read_mostly; /* Handle normal Linux uptimes. */ +int nr_threads __read_mostly; /* The idle threads do not count.. */ -static int max_threads; /* tunable limit on nr_threads */ +static int max_threads __read_mostly; /* tunable limit on nr_threads */ #define NAMED_ARRAY_INDEX(x) [x] = __stringify(x) -- 1.9.1