[GIT PULL] scheduler fixes

Ingo Molnar
2025-04-06T16:55:08Z

Linus,

Please pull the latest sched/urgent Git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched-urgent-2025-04-06

# HEAD: 169eae7711ea4b745e2d33d53e7b88689b10e1a0 rseq: Eliminate useless task_work on execve

Miscellaneous scheduler fixes/updates:

- Fix a nonsensical Kconfig combination
- Remove an unnecessary rseq-notification

Thanks,

Ingo

------------------>
Mathieu Desnoyers (1):
rseq: Eliminate useless task_work on execve

Oleg Nesterov (1):
sched/isolation: Make CONFIG_CPU_ISOLATION depend on CONFIG_SMP

fs/exec.c | 3 ++-
init/Kconfig | 2 +-
kernel/sched/core.c | 1 -
3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/exec.c b/fs/exec.c
index 5d1c0d2dc403..8e4ea5f1e64c 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1864,9 +1864,9 @@ static int bprm_execve(struct linux_binprm *bprm)
goto out;

sched_mm_cid_after_execve(current);
+ rseq_execve(current);
/* execve succeeded */
current->in_execve = 0;
- rseq_execve(current);
user_events_execve(current);
acct_update_integrals(current);
task_numa_free(current, false);
@@ -1883,6 +1883,7 @@ static int bprm_execve(struct linux_binprm *bprm)
force_fatal_sig(SIGSEGV);

sched_mm_cid_after_execve(current);
+ rseq_set_notify_resume(current);
current->in_execve = 0;

return retval;
diff --git a/init/Kconfig b/init/Kconfig
index 681f38ee68db..ab9b0c2c3d52 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -709,7 +709,7 @@ endmenu # "CPU/Task time and stats accounting"

config CPU_ISOLATION
bool "CPU isolation"
- depends on SMP || COMPILE_TEST
+ depends on SMP
default y
help
Make sure that CPUs running critical tasks are not disturbed by
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index cfaca3040b2f..c81cf642dba0 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -10703,7 +10703,6 @@ void sched_mm_cid_after_execve(struct task_struct *t)
smp_mb();
t->last_mm_cid = t->mm_cid = mm_cid_get(rq, t, mm);
}
- rseq_set_notify_resume(t);
}

void sched_mm_cid_fork(struct task_struct *t)