[RFC PATCH 1/2] arm64: hw_breakpoint: convert CPU hotplug notifier to new infrastructure
From: bigeasy@linutronix.de (Sebastian Andrzej Siewior)
Date: 2016-08-26 11:28:06
On 2016-08-26 11:35:57 [+0100], Will Deacon wrote:
quoted hunk ↗ jump to hunk
diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c index 26a6bf77d272..948b73148d56 100644 --- a/arch/arm64/kernel/hw_breakpoint.c +++ b/arch/arm64/kernel/hw_breakpoint.c@@ -857,7 +857,7 @@ void hw_breakpoint_thread_switch(struct task_struct *next)
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-static int hw_breakpoint_reset_notify(struct notifier_block *self,
- unsigned long action,
- void *hcpu)
-{
- if ((action & ~CPU_TASKS_FROZEN) == CPU_ONLINE) {
- local_irq_disable();
- hw_breakpoint_reset(NULL);so the old one was invoked at CPU_ONLINE time.
- local_irq_enable(); - } - return NOTIFY_OK; + return 0; }
?
quoted hunk ↗ jump to hunk
@@ -919,36 +905,34 @@ static inline void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *))
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+ /* + * Reset the breakpoint resources. We assume that a halting + * debugger will leave the world in a nice state for us. + */ + ret = cpuhp_setup_state(CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING, + "CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING", + hw_breakpoint_reset, NULL);
But this will move it to CPU_STARTING. May I ask why? Sebastian