From e7407dcc69e077ac34a527842db916abfbc458df Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 9 May 2007 02:34:04 -0700 Subject: [PATCH] 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 Cc: Gautham Shenoy Signed-off-by: Heiko Carstens Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/cpu.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/kernel/cpu.c b/kernel/cpu.c index 48810498b35..1a823944e97 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -97,7 +97,7 @@ static inline void check_for_tasks(int cpu) (!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 @@ static int take_cpu_down(void *unused) /* 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 @@ static int _cpu_down(unsigned int cpu) 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 @@ static int _cpu_down(unsigned int cpu) 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 @@ static int _cpu_down(unsigned int cpu) 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); -- 2.20.1