diff options
| -rw-r--r-- | tools/testing/selftests/powerpc/pmu/.gitignore | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/pmu/Makefile | 8 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/pmu/count_stcx_fail.c | 161 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/pmu/loop.S | 35 |
4 files changed, 203 insertions, 2 deletions
diff --git a/tools/testing/selftests/powerpc/pmu/.gitignore b/tools/testing/selftests/powerpc/pmu/.gitignore index ff7896903d7b..f69b1e2641a1 100644 --- a/tools/testing/selftests/powerpc/pmu/.gitignore +++ b/tools/testing/selftests/powerpc/pmu/.gitignore @@ -2,3 +2,4 @@ count_instructions l3_bank_test per_event_excludes +count_stcx_fail diff --git a/tools/testing/selftests/powerpc/pmu/Makefile b/tools/testing/selftests/powerpc/pmu/Makefile index 19046db995fe..904672fb78dd 100644 --- a/tools/testing/selftests/powerpc/pmu/Makefile +++ b/tools/testing/selftests/powerpc/pmu/Makefile @@ -2,7 +2,7 @@ noarg: $(MAKE) -C ../ -TEST_GEN_PROGS := count_instructions l3_bank_test per_event_excludes +TEST_GEN_PROGS := count_instructions count_stcx_fail l3_bank_test per_event_excludes EXTRA_SOURCES := ../harness.c event.c lib.c ../utils.c top_srcdir = ../../../../.. @@ -13,8 +13,12 @@ all: $(TEST_GEN_PROGS) ebb $(TEST_GEN_PROGS): $(EXTRA_SOURCES) # loop.S can only be built 64-bit +$(OUTPUT)/count_instructions: CFLAGS += -m64 $(OUTPUT)/count_instructions: loop.S count_instructions.c $(EXTRA_SOURCES) - $(CC) $(CFLAGS) -m64 -o $@ $^ + +$(OUTPUT)/count_stcx_fail: CFLAGS += -m64 +$(OUTPUT)/count_stcx_fail: loop.S $(EXTRA_SOURCES) + $(OUTPUT)/per_event_excludes: ../utils.c diff --git a/tools/testing/selftests/powerpc/pmu/count_stcx_fail.c b/tools/testing/selftests/powerpc/pmu/count_stcx_fail.c new file mode 100644 index 000000000000..7b4ac4537702 --- /dev/null +++ b/tools/testing/selftests/powerpc/pmu/count_stcx_fail.c @@ -0,0 +1,161 @@ +/* + * Copyright 2013, Michael Ellerman, IBM Corp. + * Licensed under GPLv2. + */ + +#define _GNU_SOURCE + +#include <stdio.h> +#include <stdbool.h> +#include <string.h> +#include <sys/prctl.h> + +#include "event.h" +#include "utils.h" +#include "lib.h" + +extern void thirty_two_instruction_loop_with_ll_sc(u64 loops, u64 *ll_sc_target); + +static void setup_event(struct event *e, u64 config, int type, char *name) +{ + event_init_opts(e, config, type, name); + + e->attr.disabled = 1; + e->attr.exclude_kernel = 1; + e->attr.exclude_hv = 1; + e->attr.exclude_idle = 1; +} + +static int do_count_loop(struct event *events, u64 instructions, + u64 overhead, bool report) +{ + s64 difference, expected; + double percentage; + u64 dummy; + + prctl(PR_TASK_PERF_EVENTS_ENABLE); + + /* Run for 1M instructions */ + thirty_two_instruction_loop_with_ll_sc(instructions >> 5, &dummy); + + prctl(PR_TASK_PERF_EVENTS_DISABLE); + + event_read(&events[0]); + event_read(&events[1]); + event_read(&events[2]); + + expected = instructions + overhead + (events[2].result.value * 10); + difference = events[0].result.value - expected; + percentage = (double)difference / events[0].result.value * 100; + + if (report) { + printf("-----\n"); + event_report(&events[0]); + event_report(&events[1]); + event_report(&events[2]); + + printf("Looped for %llu instructions, overhead %llu\n", instructions, overhead); + printf("Expected %llu\n", expected); + printf("Actual %llu\n", events[0].result.value); + printf("Delta %lld, %f%%\n", difference, percentage); + } + + event_reset(&events[0]); + event_reset(&events[1]); + event_reset(&events[2]); + + if (difference < 0) + difference = -difference; + + /* Tolerate a difference below 0.0001 % */ + difference *= 10000 * 100; + if (difference / events[0].result.value) + return -1; + + return 0; +} + +/* Count how many instructions it takes to do a null loop */ +static u64 determine_overhead(struct event *events) +{ + u64 current, overhead; + int i; + + do_count_loop(events, 0, 0, false); + overhead = events[0].result.value; + + for (i = 0; i < 100; i++) { + do_count_loop(events, 0, 0, false); + current = events[0].result.value; + if (current < overhead) { + printf("Replacing overhead %llu with %llu\n", overhead, current); + overhead = current; + } + } + + return overhead; +} + +#define PM_MRK_STCX_FAIL 0x03e158 +#define PM_STCX_FAIL 0x01e058 + +static int test_body(void) +{ + struct event events[3]; + u64 overhead; + + setup_event(&events[0], PERF_COUNT_HW_INSTRUCTIONS, PERF_TYPE_HARDWARE, "instructions"); + setup_event(&events[1], PERF_COUNT_HW_CPU_CYCLES, PERF_TYPE_HARDWARE, "cycles"); + setup_event(&events[2], PM_STCX_FAIL, PERF_TYPE_RAW, "stcx_fail"); + + if (event_open(&events[0])) { + perror("perf_event_open"); + return -1; + } + + if (event_open_with_group(&events[1], events[0].fd)) { + perror("perf_event_open"); + return -1; + } + + if (event_open_with_group(&events[2], events[0].fd)) { + perror("perf_event_open"); + return -1; + } + + overhead = determine_overhead(events); + printf("Overhead of null loop: %llu instructions\n", overhead); + + /* Run for 1Mi instructions */ + FAIL_IF(do_count_loop(events, 1000000, overhead, true)); + + /* Run for 10Mi instructions */ + FAIL_IF(do_count_loop(events, 10000000, overhead, true)); + + /* Run for 100Mi instructions */ + FAIL_IF(do_count_loop(events, 100000000, overhead, true)); + + /* Run for 1Bi instructions */ + FAIL_IF(do_count_loop(events, 1000000000, overhead, true)); + + /* Run for 16Bi instructions */ + FAIL_IF(do_count_loop(events, 16000000000, overhead, true)); + + /* Run for 64Bi instructions */ + FAIL_IF(do_count_loop(events, 64000000000, overhead, true)); + + event_close(&events[0]); + event_close(&events[1]); + + return 0; +} + +static int count_ll_sc(void) +{ + return eat_cpu(test_body); +} + +int main(void) +{ + return test_harness(count_ll_sc, "count_ll_sc"); +} diff --git a/tools/testing/selftests/powerpc/pmu/loop.S b/tools/testing/selftests/powerpc/pmu/loop.S index 8cc9b5e2c9de..c52ba09b6fed 100644 --- a/tools/testing/selftests/powerpc/pmu/loop.S +++ b/tools/testing/selftests/powerpc/pmu/loop.S @@ -41,3 +41,38 @@ FUNC_START(thirty_two_instruction_loop) subi r3,r3,1 b FUNC_NAME(thirty_two_instruction_loop) FUNC_END(thirty_two_instruction_loop) + +FUNC_START(thirty_two_instruction_loop_with_ll_sc) + cmpdi r3,0 + beqlr + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 # 5 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 +1: ldarx r6,0,r4 # 10 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 # 15 + addi r5,r5,1 + addi r5,r5,1 + stdcx. r6,0,r4 + bne- 1b + addi r5,r5,1 # 20 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 # 25 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 + addi r5,r5,1 # 30 + subi r3,r3,1 + b FUNC_NAME(thirty_two_instruction_loop_with_ll_sc) +FUNC_END(thirty_two_instruction_loop_with_ll_sc) |