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[S390] Make sure enabled wait psw is loaded in default_idle.

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If both NO_IDLE_HZ and VIRT_TIMER are disabled default_idle won't load
an enabled wait psw and busy loop instead. This is because the
idle_chain is empty and the return value of atomic_notifier_call_chain
will be NOTIFY_DONE, which causes default_idle to return instead of
loading an enabled wait psw.
Fix this by calling __atomic_notifier_call_chain instead and add proper
return value handling.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens
2008-02-19 15:29:26 +01:00
committed by Martin Schwidefsky
parent 057c5cb35e
commit 11ab244c9f
1 changed files with 9 additions and 6 deletions
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15
arch/s390/kernel/process.c
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@@ -114,24 +114,27 @@ extern void s390_handle_mcck(void);
static void default_idle(void) static void default_idle(void)
{ {
int cpu, rc; int cpu, rc;
int nr_calls = 0;
void *hcpu;
#ifdef CONFIG_SMP #ifdef CONFIG_SMP
struct s390_idle_data *idle; struct s390_idle_data *idle;
#endif #endif
/* CPU is going idle. */ /* CPU is going idle. */
cpu = smp_processor_id(); cpu = smp_processor_id();
hcpu = (void *)(long)cpu;
local_irq_disable(); local_irq_disable();
if (need_resched()) { if (need_resched()) {
local_irq_enable(); local_irq_enable();
return; return;
} }
rc = atomic_notifier_call_chain(&idle_chain, rc = __atomic_notifier_call_chain(&idle_chain, S390_CPU_IDLE, hcpu, -1,
S390_CPU_IDLE, (void *)(long) cpu); &nr_calls);
if (rc != NOTIFY_OK && rc != NOTIFY_DONE) if (rc == NOTIFY_BAD) {
BUG(); nr_calls--;
if (rc != NOTIFY_OK) { __atomic_notifier_call_chain(&idle_chain, S390_CPU_NOT_IDLE,
hcpu, nr_calls, NULL);
local_irq_enable(); local_irq_enable();
return; return;
} }