call cpu_chain with CPU_DOWN_FAILED if CPU_DOWN_PREPARE failed
This makes cpu hotplug symmetrical: if CPU_UP_PREPARE fails we get
CPU_UP_CANCELED, so we can undo what ever happened on PREPARE. The same
should happen for CPU_DOWN_PREPARE.
[akpm@linux-foundation.org: fix for reduce-size-of-task_struct-on-64-bit-machines]
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Gautham Shenoy <ego@in.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 4881049..1a82394 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -97,7 +97,7 @@
(!cputime_eq(p->utime, cputime_zero) ||
!cputime_eq(p->stime, cputime_zero)))
printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d\
- (state = %ld, flags = %lx) \n",
+ (state = %ld, flags = %x) \n",
p->comm, p->pid, cpu, p->state, p->flags);
}
write_unlock_irq(&tasklist_lock);
@@ -122,9 +122,10 @@
/* Requires cpu_add_remove_lock to be held */
static int _cpu_down(unsigned int cpu)
{
- int err;
+ int err, nr_calls = 0;
struct task_struct *p;
cpumask_t old_allowed, tmp;
+ void *hcpu = (void *)(long)cpu;
if (num_online_cpus() == 1)
return -EBUSY;
@@ -132,11 +133,12 @@
if (!cpu_online(cpu))
return -EINVAL;
- raw_notifier_call_chain(&cpu_chain, CPU_LOCK_ACQUIRE,
- (void *)(long)cpu);
- err = raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE,
- (void *)(long)cpu);
+ raw_notifier_call_chain(&cpu_chain, CPU_LOCK_ACQUIRE, hcpu);
+ err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE,
+ hcpu, -1, &nr_calls);
if (err == NOTIFY_BAD) {
+ __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED, hcpu,
+ nr_calls, NULL);
printk("%s: attempt to take down CPU %u failed\n",
__FUNCTION__, cpu);
err = -EINVAL;
@@ -156,7 +158,7 @@
if (IS_ERR(p) || cpu_online(cpu)) {
/* CPU didn't die: tell everyone. Can't complain. */
if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED,
- (void *)(long)cpu) == NOTIFY_BAD)
+ hcpu) == NOTIFY_BAD)
BUG();
if (IS_ERR(p)) {
@@ -178,8 +180,7 @@
put_cpu();
/* CPU is completely dead: tell everyone. Too late to complain. */
- if (raw_notifier_call_chain(&cpu_chain, CPU_DEAD,
- (void *)(long)cpu) == NOTIFY_BAD)
+ if (raw_notifier_call_chain(&cpu_chain, CPU_DEAD, hcpu) == NOTIFY_BAD)
BUG();
check_for_tasks(cpu);