diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build index 87bf3edb037c..62ca0174d5e1 100644 --- a/tools/perf/tests/Build +++ b/tools/perf/tests/Build @@ -20,6 +20,7 @@ perf-y += hists_cumulate.o perf-y += python-use.o perf-y += bp_signal.o perf-y += bp_signal_overflow.o +perf-y += bp_account.o perf-y += task-exit.o perf-y += sw-clock.o perf-y += mmap-thread-lookup.o diff --git a/tools/perf/tests/bp_account.c b/tools/perf/tests/bp_account.c new file mode 100644 index 000000000000..2f75fa0c4fef --- /dev/null +++ b/tools/perf/tests/bp_account.c @@ -0,0 +1,195 @@ +/* + * Powerpc needs __SANE_USERSPACE_TYPES__ before to select + * 'int-ll64.h' and avoid compile warnings when printing __u64 with %llu. + */ +#define __SANE_USERSPACE_TYPES__ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "tests.h" +#include "debug.h" +#include "perf.h" +#include "cloexec.h" + +volatile long the_var; + +static noinline int test_function(void) +{ + return 0; +} + +static int __event(bool is_x, void *addr, struct perf_event_attr *attr) +{ + int fd; + + memset(attr, 0, sizeof(struct perf_event_attr)); + attr->type = PERF_TYPE_BREAKPOINT; + attr->size = sizeof(struct perf_event_attr); + + attr->config = 0; + attr->bp_type = is_x ? HW_BREAKPOINT_X : HW_BREAKPOINT_W; + attr->bp_addr = (unsigned long) addr; + attr->bp_len = sizeof(long); + + attr->sample_period = 1; + attr->sample_type = PERF_SAMPLE_IP; + + attr->exclude_kernel = 1; + attr->exclude_hv = 1; + + fd = sys_perf_event_open(attr, -1, 0, -1, + perf_event_open_cloexec_flag()); + if (fd < 0) { + pr_debug("failed opening event %llx\n", attr->config); + return TEST_FAIL; + } + + return fd; +} + +static int wp_event(void *addr, struct perf_event_attr *attr) +{ + return __event(false, addr, attr); +} + +static int bp_event(void *addr, struct perf_event_attr *attr) +{ + return __event(true, addr, attr); +} + +static int bp_accounting(int wp_cnt, int share) +{ + struct perf_event_attr attr, attr_mod, attr_new; + int i, fd[wp_cnt], fd_wp, ret; + + for (i = 0; i < wp_cnt; i++) { + fd[i] = wp_event((void *)&the_var, &attr); + TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1); + pr_debug("wp %d created\n", i); + } + + attr_mod = attr; + attr_mod.bp_type = HW_BREAKPOINT_X; + attr_mod.bp_addr = (unsigned long) test_function; + + ret = ioctl(fd[0], PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr_mod); + TEST_ASSERT_VAL("failed to modify wp\n", ret == 0); + + pr_debug("wp 0 modified to bp\n"); + + if (!share) { + fd_wp = wp_event((void *)&the_var, &attr_new); + TEST_ASSERT_VAL("failed to create max wp\n", fd_wp != -1); + pr_debug("wp max created\n"); + } + + for (i = 0; i < wp_cnt; i++) + close(fd[i]); + + return 0; +} + +static int detect_cnt(bool is_x) +{ + struct perf_event_attr attr; + void *addr = is_x ? test_function : (void *) &the_var; + int fd[100], cnt = 0, i; + + while (1) { + fd[cnt] = __event(is_x, addr, &attr); + + if (fd[cnt] < 0) + break; + + if (cnt == 100) { + pr_debug("way too many debug registers, fix the test\n"); + return 0; + } + + cnt++; + } + + for (i = 0; i < cnt; i++) + close(fd[i]); + + return cnt; +} + +static int detect_ioctl(void) +{ + struct perf_event_attr attr; + int fd, ret = 1; + + fd = wp_event((void *) &the_var, &attr); + if (fd > 0) { + ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr); + close(fd); + } + + return ret ? 0 : 1; +} + +static int detect_share(int wp_cnt, int bp_cnt) +{ + struct perf_event_attr attr; + int i, fd[wp_cnt + bp_cnt], ret; + + for (i = 0; i < wp_cnt; i++) { + fd[i] = wp_event((void *)&the_var, &attr); + TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1); + } + + for (; i < (bp_cnt + wp_cnt); i++) { + fd[i] = bp_event((void *)test_function, &attr); + if (fd[i] == -1) + break; + } + + ret = i != (bp_cnt + wp_cnt); + + while (i--) + close(fd[i]); + + return ret; +} + +/* + * This test does following: + * - detects the number of watch/break-points, + * skip test if any is missing + * - detects PERF_EVENT_IOC_MODIFY_ATTRIBUTES ioctl, + * skip test if it's missing + * - detects if watchpoints and breakpoints share + * same slots + * - create all possible watchpoints on cpu 0 + * - change one of it to breakpoint + * - in case wp and bp do not share slots, + * we create another watchpoint to ensure + * the slot accounting is correct + */ +int test__bp_accounting(struct test *test __maybe_unused, int subtest __maybe_unused) +{ + int has_ioctl = detect_ioctl(); + int wp_cnt = detect_cnt(false); + int bp_cnt = detect_cnt(true); + int share = detect_share(wp_cnt, bp_cnt); + + pr_debug("watchpoints count %d, breakpoints count %d, has_ioctl %d, share %d\n", + wp_cnt, bp_cnt, has_ioctl, share); + + if (!wp_cnt || !bp_cnt || !has_ioctl) + return TEST_SKIP; + + return bp_accounting(wp_cnt, share); +} diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c index fafa014240cd..38bf109ce106 100644 --- a/tools/perf/tests/builtin-test.c +++ b/tools/perf/tests/builtin-test.c @@ -115,6 +115,10 @@ static struct test generic_tests[] = { .func = test__bp_signal_overflow, .is_supported = test__bp_signal_is_supported, }, + { + .desc = "Breakpoint accounting", + .func = test__bp_accounting, + }, { .desc = "Number of exit events of a simple workload", .func = test__task_exit, diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h index 2862b80bc288..9f51edac44ae 100644 --- a/tools/perf/tests/tests.h +++ b/tools/perf/tests/tests.h @@ -58,6 +58,7 @@ int test__hists_link(struct test *test, int subtest); int test__python_use(struct test *test, int subtest); int test__bp_signal(struct test *test, int subtest); int test__bp_signal_overflow(struct test *test, int subtest); +int test__bp_accounting(struct test *test, int subtest); int test__task_exit(struct test *test, int subtest); int test__mem(struct test *test, int subtest); int test__sw_clock_freq(struct test *test, int subtest);