Commit 407eb43a authored by Rob Herring's avatar Rob Herring Committed by Arnaldo Carvalho de Melo
Browse files

libperf: Add arm64 support to perf_mmap__read_self() 



Add the arm64 variants for read_perf_counter() and read_timestamp().
Unfortunately the counter number is encoded into the instruction, so the
code is a bit verbose to enumerate all possible counters.

Tested-by: default avatarMasayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: default avatarRob Herring <robh@kernel.org>
Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
Tested-by: default avatarJohn Garry <john.garry@huawei.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/r/20220201214056.702854-1-robh@kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
parent 4f249273

tools/lib/perf/mmap.c

+98 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ 
#include <internal/lib.h>

#include <linux/kernel.h>

#include <linux/math64.h>

#include <linux/stringify.h>

#include "internal.h"



void perf_mmap__init(struct perf_mmap *map, struct perf_mmap *prev,
@@ -294,6 +295,103 @@ static u64 read_timestamp(void) 


	return low | ((u64)high) << 32;

}

#elif defined(__aarch64__)

#define read_sysreg(r) ({						\

	u64 __val;							\

	asm volatile("mrs %0, " __stringify(r) : "=r" (__val));		\

	__val;								\

})



static u64 read_pmccntr(void)

{

	return read_sysreg(pmccntr_el0);

}



#define PMEVCNTR_READ(idx)					\

	static u64 read_pmevcntr_##idx(void) {			\

		return read_sysreg(pmevcntr##idx##_el0);	\

	}



PMEVCNTR_READ(0);

PMEVCNTR_READ(1);

PMEVCNTR_READ(2);

PMEVCNTR_READ(3);

PMEVCNTR_READ(4);

PMEVCNTR_READ(5);

PMEVCNTR_READ(6);

PMEVCNTR_READ(7);

PMEVCNTR_READ(8);

PMEVCNTR_READ(9);

PMEVCNTR_READ(10);

PMEVCNTR_READ(11);

PMEVCNTR_READ(12);

PMEVCNTR_READ(13);

PMEVCNTR_READ(14);

PMEVCNTR_READ(15);

PMEVCNTR_READ(16);

PMEVCNTR_READ(17);

PMEVCNTR_READ(18);

PMEVCNTR_READ(19);

PMEVCNTR_READ(20);

PMEVCNTR_READ(21);

PMEVCNTR_READ(22);

PMEVCNTR_READ(23);

PMEVCNTR_READ(24);

PMEVCNTR_READ(25);

PMEVCNTR_READ(26);

PMEVCNTR_READ(27);

PMEVCNTR_READ(28);

PMEVCNTR_READ(29);

PMEVCNTR_READ(30);



/*

 * Read a value direct from PMEVCNTR<idx>

 */

static u64 read_perf_counter(unsigned int counter)

{

	static u64 (* const read_f[])(void) = {

		read_pmevcntr_0,

		read_pmevcntr_1,

		read_pmevcntr_2,

		read_pmevcntr_3,

		read_pmevcntr_4,

		read_pmevcntr_5,

		read_pmevcntr_6,

		read_pmevcntr_7,

		read_pmevcntr_8,

		read_pmevcntr_9,

		read_pmevcntr_10,

		read_pmevcntr_11,

		read_pmevcntr_13,

		read_pmevcntr_12,

		read_pmevcntr_14,

		read_pmevcntr_15,

		read_pmevcntr_16,

		read_pmevcntr_17,

		read_pmevcntr_18,

		read_pmevcntr_19,

		read_pmevcntr_20,

		read_pmevcntr_21,

		read_pmevcntr_22,

		read_pmevcntr_23,

		read_pmevcntr_24,

		read_pmevcntr_25,

		read_pmevcntr_26,

		read_pmevcntr_27,

		read_pmevcntr_28,

		read_pmevcntr_29,

		read_pmevcntr_30,

		read_pmccntr

	};



	if (counter < ARRAY_SIZE(read_f))

		return (read_f[counter])();



	return 0;

}



static u64 read_timestamp(void) { return read_sysreg(cntvct_el0); }



#else

static u64 read_perf_counter(unsigned int counter __maybe_unused) { return 0; }

static u64 read_timestamp(void) { return 0; }

tools/lib/perf/tests/test-evsel.c

+4 −1
Original line number Diff line number Diff line
@@ -130,6 +130,9 @@ static int test_stat_user_read(int event) 
	struct perf_event_attr attr = {

		.type	= PERF_TYPE_HARDWARE,

		.config	= event,

#ifdef __aarch64__

		.config1 = 0x2,		/* Request user access */

#endif

	};

	int err, i;
@@ -150,7 +153,7 @@ static int test_stat_user_read(int event) 
	pc = perf_evsel__mmap_base(evsel, 0, 0);

	__T("failed to get mmapped address", pc);



#if defined(__i386__) || defined(__x86_64__)

#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)

	__T("userspace counter access not supported", pc->cap_user_rdpmc);

	__T("userspace counter access not enabled", pc->index);

	__T("userspace counter width not set", pc->pmc_width >= 32);