diff options
author | Jiri Olsa <jolsa@kernel.org> | 2018-03-12 14:45:48 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2018-03-13 15:23:37 +0100 |
commit | 032db28e5fa3594dfa3df585c54d8b612657f537 (patch) | |
tree | c06c3c6a0b83ab43954fca3217a723f98fbb47a6 /tools/perf/tests/bp_account.c | |
parent | 5f970521d3279d99adcdebf329631e36cb9f0deb (diff) | |
download | linux-032db28e5fa3594dfa3df585c54d8b612657f537.tar.gz |
perf tests: Add breakpoint accounting/modify test
Adding test that:
- 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
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Milind Chabbi <chabbi.milind@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <onestero@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180312134548.31532-9-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'tools/perf/tests/bp_account.c')
-rw-r--r-- | tools/perf/tests/bp_account.c | 195 |
1 files changed, 195 insertions, 0 deletions
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 <linux/types.h> to select + * 'int-ll64.h' and avoid compile warnings when printing __u64 with %llu. + */ +#define __SANE_USERSPACE_TYPES__ + +#include <stdlib.h> +#include <stdio.h> +#include <unistd.h> +#include <string.h> +#include <sys/ioctl.h> +#include <time.h> +#include <fcntl.h> +#include <signal.h> +#include <sys/mman.h> +#include <linux/compiler.h> +#include <linux/hw_breakpoint.h> +#include <sys/ioctl.h> + +#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); +} |