From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934855AbeAKPxf (ORCPT + 1 other); Thu, 11 Jan 2018 10:53:35 -0500 Received: from mail-eopbgr10102.outbound.protection.outlook.com ([40.107.1.102]:14157 "EHLO EUR02-HE1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932223AbeAKPxD (ORCPT ); Thu, 11 Jan 2018 10:53:03 -0500 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=ktkhai@virtuozzo.com; Subject: [PATCH 3/4] tty: Iterate only thread group leaders in __do_SAK() From: Kirill Tkhai To: linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, jslaby@suse.com, viro@zeniv.linux.org.uk, keescook@chromium.org, serge@hallyn.com, james.l.morris@oracle.com, luto@kernel.org, john.johansen@canonical.com, oleg@redhat.com, mingo@kernel.org, akpm@linux-foundation.org, mhocko@suse.com, peterz@infradead.org, ktkhai@virtuozzo.com Date: Thu, 11 Jan 2018 18:50:23 +0300 Message-ID: <151568582337.6090.931248807289363396.stgit@localhost.localdomain> In-Reply-To: <151568564127.6090.3546718160925256054.stgit@localhost.localdomain> References: <151568564127.6090.3546718160925256054.stgit@localhost.localdomain> User-Agent: StGit/0.18 MIME-Version: 1.0 Content-Type: text/plain; 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So, skip the pointless iterations and make __do_SAK() faster. Signed-off-by: Kirill Tkhai --- drivers/tty/tty_io.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index dc60aeea87d8..94813ae40983 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -2704,7 +2704,7 @@ void __do_SAK(struct tty_struct *tty) #ifdef TTY_SOFT_SAK tty_hangup(tty); #else - struct task_struct *g, *p; + struct task_struct *p; struct pid *session; int i; @@ -2725,7 +2725,7 @@ void __do_SAK(struct tty_struct *tty) } while_each_pid_task(session, PIDTYPE_SID, p); /* Now kill any processes that happen to have the tty open */ - do_each_thread(g, p) { + for_each_process(p) { if (p->signal->tty == tty) { tty_notice(tty, "SAK: killed process %d (%s): by controlling tty\n", task_pid_nr(p), p->comm); @@ -2740,7 +2740,7 @@ void __do_SAK(struct tty_struct *tty) force_sig(SIGKILL, p); } task_unlock(p); - } while_each_thread(g, p); + } read_unlock(&tasklist_lock); #endif }