From d35e578ac2d9b154c967967ae9593093d903c0e8 Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Thu, 1 Oct 2020 10:40:27 +0200
Subject: [PATCH 201/201] chrt: use SCHED_FLAG_RESET_ON_FORK for
sched_setattr()
Reviewed by many people, used for years (but probably nobody uses
SCHED_DEADLINE with reset-on-fork), but we all missed:
- sched_setscheduler() uses SCHED_RESET_ON_FORK (0x40000000)
- sched_setattr() uses SCHED_FLAG_RESET_ON_FORK (0x01)
Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1883013
Signed-off-by: Karel Zak <kzak@redhat.com>
---
schedutils/chrt.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/schedutils/chrt.c b/schedutils/chrt.c
index 4cceff2d7..84e76f17b 100644
--- a/schedutils/chrt.c
+++ b/schedutils/chrt.c
@@ -123,7 +123,7 @@ struct chrt_ctl {
uint64_t period;
unsigned int all_tasks : 1, /* all threads of the PID */
- reset_on_fork : 1, /* SCHED_RESET_ON_FORK */
+ reset_on_fork : 1, /* SCHED_RESET_ON_FORK or SCHED_FLAG_RESET_ON_FORK */
altered : 1, /* sched_set**() used */
verbose : 1; /* verbose output */
};
@@ -376,9 +376,10 @@ static int set_sched_one(struct chrt_ctl *ctl, pid_t pid)
sa.sched_period = ctl->period;
sa.sched_deadline = ctl->deadline;
-# ifdef SCHED_RESET_ON_FORK
+# ifdef SCHED_FLAG_RESET_ON_FORK
+ /* Don't use SCHED_RESET_ON_FORK for sched_setattr()! */
if (ctl->reset_on_fork)
- sa.sched_flags |= SCHED_RESET_ON_FORK;
+ sa.sched_flags |= SCHED_FLAG_RESET_ON_FORK;
# endif
errno = 0;
return sched_setattr(pid, &sa, 0);
--
2.28.0