diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2013-06-14 15:16:35 (GMT) |
|---|---|---|
| committer | Scott Wood <scottwood@freescale.com> | 2015-02-13 22:21:04 (GMT) |
| commit | 0464cead458c293d97265fa212a0b064bd3fa19c (patch) | |
| tree | eb5b5143578f32fee96066590fa6cfaa3d851397 /kernel | |
| parent | 6adf6a40918b49ac563fb1db9b47eacb7925dd3f (diff) | |
| download | linux-fsl-qoriq-0464cead458c293d97265fa212a0b064bd3fa19c.tar.xz | |
kernel/hotplug: restore original cpu mask oncpu/down
If a task which is allowed to run only on CPU X puts CPU Y down then it
will be allowed on all CPUs but the on CPU Y after it comes back from
kernel. This patch ensures that we don't lose the initial setting unless
the CPU the task is running is going down.
Cc: stable-rt@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cpu.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 57ff83e..423ba34 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -573,6 +573,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) .hcpu = hcpu, }; cpumask_var_t cpumask; + cpumask_var_t cpumask_org; if (num_online_cpus() == 1) return -EBUSY; @@ -583,6 +584,12 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) /* Move the downtaker off the unplug cpu */ if (!alloc_cpumask_var(&cpumask, GFP_KERNEL)) return -ENOMEM; + if (!alloc_cpumask_var(&cpumask_org, GFP_KERNEL)) { + free_cpumask_var(cpumask); + return -ENOMEM; + } + + cpumask_copy(cpumask_org, tsk_cpus_allowed(current)); cpumask_andnot(cpumask, cpu_online_mask, cpumask_of(cpu)); set_cpus_allowed_ptr(current, cpumask); free_cpumask_var(cpumask); @@ -591,7 +598,8 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) if (mycpu == cpu) { printk(KERN_ERR "Yuck! Still on unplug CPU\n!"); migrate_enable(); - return -EBUSY; + err = -EBUSY; + goto restore_cpus; } cpu_hotplug_begin(); @@ -650,6 +658,9 @@ out_cancel: cpu_hotplug_done(); if (!err) cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu); +restore_cpus: + set_cpus_allowed_ptr(current, cpumask_org); + free_cpumask_var(cpumask_org); return err; } |