Commit 1f7c232e authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

x86/perf/amd: Remove tracing from perf_lopwr_cb() 



The perf_lopwr_cb() function is called from the idle routines; there
is no RCU there, we must not enter tracing.

Use __always_inline, noidle annotations and existing no-trace methods.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Tested-by: default avatarTony Lindgren <tony@atomide.com>
Tested-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Acked-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: default avatarFrederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195539.392862891@infradead.org
parent 28c8e088

arch/x86/events/amd/brs.c

+5 −8
Original line number Diff line number Diff line
@@ -41,18 +41,15 @@ static inline unsigned int brs_to(int idx) 
	return MSR_AMD_SAMP_BR_FROM + 2 * idx + 1;

}



static inline void set_debug_extn_cfg(u64 val)

static __always_inline void set_debug_extn_cfg(u64 val)

{

	/* bits[4:3] must always be set to 11b */

	wrmsrl(MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3);

	__wrmsr(MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3, val >> 32);

}



static inline u64 get_debug_extn_cfg(void)

static __always_inline u64 get_debug_extn_cfg(void)

{

	u64 val;



	rdmsrl(MSR_AMD_DBG_EXTN_CFG, val);

	return val;

	return __rdmsr(MSR_AMD_DBG_EXTN_CFG);

}



static bool __init amd_brs_detect(void)
@@ -405,7 +402,7 @@ void amd_pmu_brs_sched_task(struct perf_event_pmu_context *pmu_ctx, bool sched_i 
 * called from ACPI processor_idle.c or acpi_pad.c

 * with interrupts disabled

 */

void perf_amd_brs_lopwr_cb(bool lopwr_in)

void noinstr perf_amd_brs_lopwr_cb(bool lopwr_in)

{

	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);

	union amd_debug_extn_cfg cfg;

arch/x86/include/asm/perf_event.h

+1 −1
Original line number Diff line number Diff line
@@ -578,7 +578,7 @@ extern void perf_amd_brs_lopwr_cb(bool lopwr_in); 


DECLARE_STATIC_CALL(perf_lopwr_cb, perf_amd_brs_lopwr_cb);



static inline void perf_lopwr_cb(bool lopwr_in)

static __always_inline void perf_lopwr_cb(bool lopwr_in)

{

	static_call_mod(perf_lopwr_cb)(lopwr_in);

}