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Commit 9744f7b7 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Ingo Molnar
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perf/x86/amd/ibs: Convert to hotplug state machine 



Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarAnna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153333.921401190@linutronix.de


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 96b2bd38

arch/x86/events/amd/ibs.c

+28 −36
Original line number Diff line number Diff line
@@ -721,13 +721,10 @@ static __init int perf_ibs_pmu_init(struct perf_ibs *perf_ibs, char *name) 
	return ret;

}



static __init int perf_event_ibs_init(void)

static __init void perf_event_ibs_init(void)

{

	struct attribute **attr = ibs_op_format_attrs;



	if (!ibs_caps)

		return -ENODEV;	/* ibs not supported by the cpu */



	perf_ibs_pmu_init(&perf_ibs_fetch, "ibs_fetch");



	if (ibs_caps & IBS_CAPS_OPCNT) {
@@ -738,13 +735,11 @@ static __init int perf_event_ibs_init(void) 


	register_nmi_handler(NMI_LOCAL, perf_ibs_nmi_handler, 0, "perf_ibs");

	pr_info("perf: AMD IBS detected (0x%08x)\n", ibs_caps);



	return 0;

}



#else /* defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_AMD) */



static __init int perf_event_ibs_init(void) { return 0; }

static __init void perf_event_ibs_init(void) { }



#endif
@@ -921,7 +916,7 @@ static inline int get_ibs_lvt_offset(void) 
	return val & IBSCTL_LVT_OFFSET_MASK;

}



static void setup_APIC_ibs(void *dummy)

static void setup_APIC_ibs(void)

{

	int offset;
@@ -936,7 +931,7 @@ static void setup_APIC_ibs(void *dummy) 
		smp_processor_id());

}



static void clear_APIC_ibs(void *dummy)

static void clear_APIC_ibs(void)

{

	int offset;
@@ -945,18 +940,24 @@ static void clear_APIC_ibs(void *dummy) 
		setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_FIX, 1);

}



static int x86_pmu_amd_ibs_starting_cpu(unsigned int cpu)

{

	setup_APIC_ibs();

	return 0;

}



#ifdef CONFIG_PM



static int perf_ibs_suspend(void)

{

	clear_APIC_ibs(NULL);

	clear_APIC_ibs();

	return 0;

}



static void perf_ibs_resume(void)

{

	ibs_eilvt_setup();

	setup_APIC_ibs(NULL);

	setup_APIC_ibs();

}



static struct syscore_ops perf_ibs_syscore_ops = {
@@ -975,27 +976,15 @@ static inline void perf_ibs_pm_init(void) { } 


#endif



static int

perf_ibs_cpu_notifier(struct notifier_block *self, unsigned long action, void *hcpu)

static int x86_pmu_amd_ibs_dying_cpu(unsigned int cpu)

{

	switch (action & ~CPU_TASKS_FROZEN) {

	case CPU_STARTING:

		setup_APIC_ibs(NULL);

		break;

	case CPU_DYING:

		clear_APIC_ibs(NULL);

		break;

	default:

		break;

	}



	return NOTIFY_OK;

	clear_APIC_ibs();

	return 0;

}



static __init int amd_ibs_init(void)

{

	u32 caps;

	int ret = -EINVAL;



	caps = __get_ibs_caps();

	if (!caps)
@@ -1004,22 +993,25 @@ static __init int amd_ibs_init(void) 
	ibs_eilvt_setup();



	if (!ibs_eilvt_valid())

		goto out;

		return -EINVAL;



	perf_ibs_pm_init();

	cpu_notifier_register_begin();



	ibs_caps = caps;

	/* make ibs_caps visible to other cpus: */

	smp_mb();

	smp_call_function(setup_APIC_ibs, NULL, 1);

	__perf_cpu_notifier(perf_ibs_cpu_notifier);

	cpu_notifier_register_done();

	/*

	 * x86_pmu_amd_ibs_starting_cpu will be called from core on

	 * all online cpus.

	 */

	cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_IBS_STARTING,

			  "AP_PERF_X86_AMD_IBS_STARTING",

			  x86_pmu_amd_ibs_starting_cpu,

			  x86_pmu_amd_ibs_dying_cpu);



	ret = perf_event_ibs_init();

out:

	if (ret)

		pr_err("Failed to setup IBS, %d\n", ret);

	return ret;

	perf_event_ibs_init();



	return 0;

}



/* Since we need the pci subsystem to init ibs we can't do this earlier: */

include/linux/cpuhotplug.h

+1 −0
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ enum cpuhp_state { 
	CPUHP_AP_PERF_X86_UNCORE_STARTING,

	CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING,

	CPUHP_AP_PERF_X86_STARTING,

	CPUHP_AP_PERF_X86_AMD_IBS_STARTING,

	CPUHP_AP_NOTIFY_STARTING,

	CPUHP_AP_ONLINE,

	CPUHP_TEARDOWN_CPU,