From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Silverman Subject: [PATCH] Force processes to non-realtime before mm_exit Date: Tue, 10 May 2016 14:04:24 -0400 Message-ID: <1462903464-11448-1-git-send-email-brian@peloton-tech.com> Cc: Brian Silverman To: linux-rt-users@vger.kernel.org Return-path: Received: from mail-pf0-f176.google.com ([209.85.192.176]:32852 "EHLO mail-pf0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751041AbcEJSGr (ORCPT ); Tue, 10 May 2016 14:06:47 -0400 Received: by mail-pf0-f176.google.com with SMTP id 206so8478654pfu.0 for ; Tue, 10 May 2016 11:06:47 -0700 (PDT) Sender: linux-rt-users-owner@vger.kernel.org List-ID: Without this, a realtime process which has called mlockall exiting causes large latencies for other realtime processes at the same or lower priorities. This seems like a fairly common use case too, because realtime processes generally want their memory locked into RAM. Signed-off-by: Brian Silverman --- kernel/exit.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/exit.c b/kernel/exit.c index a0cf72b..68a97df 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -730,6 +730,12 @@ void do_exit(long code) tsk->exit_code = code; taskstats_exit(tsk, group_dead); + if (tsk->policy == SCHED_FIFO || tsk->policy == SCHED_RR) { + struct sched_param param = { .sched_priority = 0 }; + + sched_setscheduler_nocheck(current, SCHED_NORMAL, ¶m); + } + exit_mm(tsk); if (group_dead) -- 2.1.4