perf tests: Add framework for automated perf_event_attr tests
The idea is run perf session with kidnapping sys_perf_event_open
function. For each sys_perf_event_open call we store the perf_event_attr
data to the file to be checked later against what we expect.
You can run this by:
$ python ./tests/attr.py -d ./tests/attr/ -p ./perf -v
v2 changes:
- preserve errno value in the hook
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20121031145247.GB1027@krava.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/tests/attr.c b/tools/perf/tests/attr.c
new file mode 100644
index 0000000..55e9a87
--- /dev/null
+++ b/tools/perf/tests/attr.c
@@ -0,0 +1,140 @@
+
+/*
+ * The struct perf_event_attr test support.
+ *
+ * This test is embedded inside into perf directly and is governed
+ * by the PERF_TEST_ATTR environment variable and hook inside
+ * sys_perf_event_open function.
+ *
+ * The general idea is to store 'struct perf_event_attr' details for
+ * each event created within single perf command. Each event details
+ * are stored into separate text file. Once perf command is finished
+ * these files can be checked for values we expect for command.
+ *
+ * Besides 'struct perf_event_attr' values we also store 'fd' and
+ * 'group_fd' values to allow checking for groups created.
+ *
+ * This all is triggered by setting PERF_TEST_ATTR environment variable.
+ * It must contain name of existing directory with access and write
+ * permissions. All the event text files are stored there.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <inttypes.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include "../perf.h"
+#include "util.h"
+
+#define ENV "PERF_TEST_ATTR"
+
+bool test_attr__enabled;
+
+static char *dir;
+
+void test_attr__init(void)
+{
+ dir = getenv(ENV);
+ test_attr__enabled = (dir != NULL);
+}
+
+#define BUFSIZE 1024
+
+#define WRITE_ASS(str, fmt, data) \
+do { \
+ char buf[BUFSIZE]; \
+ size_t size; \
+ \
+ size = snprintf(buf, BUFSIZE, #str "=%"fmt "\n", data); \
+ if (1 != fwrite(buf, size, 1, file)) { \
+ perror("test attr - failed to write event file"); \
+ fclose(file); \
+ return -1; \
+ } \
+ \
+} while (0)
+
+static int store_event(struct perf_event_attr *attr, pid_t pid, int cpu,
+ int fd, int group_fd, unsigned long flags)
+{
+ FILE *file;
+ char path[PATH_MAX];
+
+ snprintf(path, PATH_MAX, "%s/event-%d-%llu-%d", dir,
+ attr->type, attr->config, fd);
+
+ file = fopen(path, "w+");
+ if (!file) {
+ perror("test attr - failed to open event file");
+ return -1;
+ }
+
+ if (fprintf(file, "[event-%d-%llu-%d]\n",
+ attr->type, attr->config, fd) < 0) {
+ perror("test attr - failed to write event file");
+ fclose(file);
+ return -1;
+ }
+
+ /* syscall arguments */
+ WRITE_ASS(fd, "d", fd);
+ WRITE_ASS(group_fd, "d", group_fd);
+ WRITE_ASS(cpu, "d", cpu);
+ WRITE_ASS(pid, "d", pid);
+ WRITE_ASS(flags, "lu", flags);
+
+ /* struct perf_event_attr */
+ WRITE_ASS(type, PRIu32, attr->type);
+ WRITE_ASS(size, PRIu32, attr->size);
+ WRITE_ASS(config, "llu", attr->config);
+ WRITE_ASS(sample_period, "llu", attr->sample_period);
+ WRITE_ASS(sample_type, "llu", attr->sample_type);
+ WRITE_ASS(read_format, "llu", attr->read_format);
+ WRITE_ASS(disabled, "d", attr->disabled);
+ WRITE_ASS(inherit, "d", attr->inherit);
+ WRITE_ASS(pinned, "d", attr->pinned);
+ WRITE_ASS(exclusive, "d", attr->exclusive);
+ WRITE_ASS(exclude_user, "d", attr->exclude_user);
+ WRITE_ASS(exclude_kernel, "d", attr->exclude_kernel);
+ WRITE_ASS(exclude_hv, "d", attr->exclude_hv);
+ WRITE_ASS(exclude_idle, "d", attr->exclude_idle);
+ WRITE_ASS(mmap, "d", attr->mmap);
+ WRITE_ASS(comm, "d", attr->comm);
+ WRITE_ASS(freq, "d", attr->freq);
+ WRITE_ASS(inherit_stat, "d", attr->inherit_stat);
+ WRITE_ASS(enable_on_exec, "d", attr->enable_on_exec);
+ WRITE_ASS(task, "d", attr->task);
+ WRITE_ASS(watermask, "d", attr->watermark);
+ WRITE_ASS(precise_ip, "d", attr->precise_ip);
+ WRITE_ASS(mmap_data, "d", attr->mmap_data);
+ WRITE_ASS(sample_id_all, "d", attr->sample_id_all);
+ WRITE_ASS(exclude_host, "d", attr->exclude_host);
+ WRITE_ASS(exclude_guest, "d", attr->exclude_guest);
+ WRITE_ASS(exclude_callchain_kernel, "d",
+ attr->exclude_callchain_kernel);
+ WRITE_ASS(exclude_callchain_user, "d",
+ attr->exclude_callchain_user);
+ WRITE_ASS(wakeup_events, PRIu32, attr->wakeup_events);
+ WRITE_ASS(bp_type, PRIu32, attr->bp_type);
+ WRITE_ASS(config1, "llu", attr->config1);
+ WRITE_ASS(config2, "llu", attr->config2);
+ WRITE_ASS(branch_sample_type, "llu", attr->branch_sample_type);
+ WRITE_ASS(sample_regs_user, "llu", attr->sample_regs_user);
+ WRITE_ASS(sample_stack_user, PRIu32, attr->sample_stack_user);
+ WRITE_ASS(optional, "d", 0);
+
+ fclose(file);
+ return 0;
+}
+
+void test_attr__open(struct perf_event_attr *attr, pid_t pid, int cpu,
+ int fd, int group_fd, unsigned long flags)
+{
+ int errno_saved = errno;
+
+ if (store_event(attr, pid, cpu, fd, group_fd, flags))
+ die("test attr FAILED");
+
+ errno = errno_saved;
+}