perf: Add 'perf sched' tool
This turn-key tool allows scheduler measurements to be
conducted and the results be displayed numerically.
First baby step towards that goal: clone the new command off of
perf trace.
Fix a few other details along the way:
- add (minimal) perf trace documentation
- reorder a few places
- list perf trace in the mainporcelain list as well
as it's a very useful utility.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
new file mode 100644
index 0000000..60228d9
--- /dev/null
+++ b/tools/perf/builtin-sched.c
@@ -0,0 +1,297 @@
+#include "builtin.h"
+
+#include "util/util.h"
+#include "util/cache.h"
+#include "util/symbol.h"
+#include "util/thread.h"
+#include "util/header.h"
+
+#include "util/parse-options.h"
+
+#include "perf.h"
+#include "util/debug.h"
+
+#include "util/trace-event.h"
+
+static char const *input_name = "perf.data";
+static int input;
+static unsigned long page_size;
+static unsigned long mmap_window = 32;
+
+static unsigned long total = 0;
+static unsigned long total_comm = 0;
+
+static struct rb_root threads;
+static struct thread *last_match;
+
+static struct perf_header *header;
+static u64 sample_type;
+
+
+static int
+process_comm_event(event_t *event, unsigned long offset, unsigned long head)
+{
+ struct thread *thread;
+
+ thread = threads__findnew(event->comm.pid, &threads, &last_match);
+
+ dump_printf("%p [%p]: PERF_EVENT_COMM: %s:%d\n",
+ (void *)(offset + head),
+ (void *)(long)(event->header.size),
+ event->comm.comm, event->comm.pid);
+
+ if (thread == NULL ||
+ thread__set_comm(thread, event->comm.comm)) {
+ dump_printf("problem processing PERF_EVENT_COMM, skipping event.\n");
+ return -1;
+ }
+ total_comm++;
+
+ return 0;
+}
+
+static int
+process_sample_event(event_t *event, unsigned long offset, unsigned long head)
+{
+ char level;
+ int show = 0;
+ struct dso *dso = NULL;
+ struct thread *thread;
+ u64 ip = event->ip.ip;
+ u64 timestamp = -1;
+ u32 cpu = -1;
+ u64 period = 1;
+ void *more_data = event->ip.__more_data;
+ int cpumode;
+
+ thread = threads__findnew(event->ip.pid, &threads, &last_match);
+
+ if (sample_type & PERF_SAMPLE_TIME) {
+ timestamp = *(u64 *)more_data;
+ more_data += sizeof(u64);
+ }
+
+ if (sample_type & PERF_SAMPLE_CPU) {
+ cpu = *(u32 *)more_data;
+ more_data += sizeof(u32);
+ more_data += sizeof(u32); /* reserved */
+ }
+
+ if (sample_type & PERF_SAMPLE_PERIOD) {
+ period = *(u64 *)more_data;
+ more_data += sizeof(u64);
+ }
+
+ dump_printf("%p [%p]: PERF_EVENT_SAMPLE (IP, %d): %d/%d: %p period: %Ld\n",
+ (void *)(offset + head),
+ (void *)(long)(event->header.size),
+ event->header.misc,
+ event->ip.pid, event->ip.tid,
+ (void *)(long)ip,
+ (long long)period);
+
+ dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
+
+ if (thread == NULL) {
+ eprintf("problem processing %d event, skipping it.\n",
+ event->header.type);
+ return -1;
+ }
+
+ cpumode = event->header.misc & PERF_EVENT_MISC_CPUMODE_MASK;
+
+ if (cpumode == PERF_EVENT_MISC_KERNEL) {
+ show = SHOW_KERNEL;
+ level = 'k';
+
+ dso = kernel_dso;
+
+ dump_printf(" ...... dso: %s\n", dso->name);
+
+ } else if (cpumode == PERF_EVENT_MISC_USER) {
+
+ show = SHOW_USER;
+ level = '.';
+
+ } else {
+ show = SHOW_HV;
+ level = 'H';
+
+ dso = hypervisor_dso;
+
+ dump_printf(" ...... dso: [hypervisor]\n");
+ }
+
+ if (sample_type & PERF_SAMPLE_RAW) {
+ struct {
+ u32 size;
+ char data[0];
+ } *raw = more_data;
+
+ /*
+ * FIXME: better resolve from pid from the struct trace_entry
+ * field, although it should be the same than this perf
+ * event pid
+ */
+ print_event(cpu, raw->data, raw->size, timestamp, thread->comm);
+ }
+ total += period;
+
+ return 0;
+}
+
+static int
+process_event(event_t *event, unsigned long offset, unsigned long head)
+{
+ trace_event(event);
+
+ switch (event->header.type) {
+ case PERF_EVENT_MMAP ... PERF_EVENT_LOST:
+ return 0;
+
+ case PERF_EVENT_COMM:
+ return process_comm_event(event, offset, head);
+
+ case PERF_EVENT_EXIT ... PERF_EVENT_READ:
+ return 0;
+
+ case PERF_EVENT_SAMPLE:
+ return process_sample_event(event, offset, head);
+
+ case PERF_EVENT_MAX:
+ default:
+ return -1;
+ }
+
+ return 0;
+}
+
+static int __cmd_sched(void)
+{
+ int ret, rc = EXIT_FAILURE;
+ unsigned long offset = 0;
+ unsigned long head = 0;
+ struct stat perf_stat;
+ event_t *event;
+ uint32_t size;
+ char *buf;
+
+ trace_report();
+ register_idle_thread(&threads, &last_match);
+
+ input = open(input_name, O_RDONLY);
+ if (input < 0) {
+ perror("failed to open file");
+ exit(-1);
+ }
+
+ ret = fstat(input, &perf_stat);
+ if (ret < 0) {
+ perror("failed to stat file");
+ exit(-1);
+ }
+
+ if (!perf_stat.st_size) {
+ fprintf(stderr, "zero-sized file, nothing to do!\n");
+ exit(0);
+ }
+ header = perf_header__read(input);
+ head = header->data_offset;
+ sample_type = perf_header__sample_type(header);
+
+ if (!(sample_type & PERF_SAMPLE_RAW))
+ die("No trace sample to read. Did you call perf record "
+ "without -R?");
+
+ if (load_kernel() < 0) {
+ perror("failed to load kernel symbols");
+ return EXIT_FAILURE;
+ }
+
+remap:
+ buf = (char *)mmap(NULL, page_size * mmap_window, PROT_READ,
+ MAP_SHARED, input, offset);
+ if (buf == MAP_FAILED) {
+ perror("failed to mmap file");
+ exit(-1);
+ }
+
+more:
+ event = (event_t *)(buf + head);
+
+ size = event->header.size;
+ if (!size)
+ size = 8;
+
+ if (head + event->header.size >= page_size * mmap_window) {
+ unsigned long shift = page_size * (head / page_size);
+ int res;
+
+ res = munmap(buf, page_size * mmap_window);
+ assert(res == 0);
+
+ offset += shift;
+ head -= shift;
+ goto remap;
+ }
+
+ size = event->header.size;
+
+
+ if (!size || process_event(event, offset, head) < 0) {
+
+ /*
+ * assume we lost track of the stream, check alignment, and
+ * increment a single u64 in the hope to catch on again 'soon'.
+ */
+
+ if (unlikely(head & 7))
+ head &= ~7ULL;
+
+ size = 8;
+ }
+
+ head += size;
+
+ if (offset + head < (unsigned long)perf_stat.st_size)
+ goto more;
+
+ rc = EXIT_SUCCESS;
+ close(input);
+
+ return rc;
+}
+
+static const char * const annotate_usage[] = {
+ "perf trace [<options>] <command>",
+ NULL
+};
+
+static const struct option options[] = {
+ OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
+ "dump raw trace in ASCII"),
+ OPT_BOOLEAN('v', "verbose", &verbose,
+ "be more verbose (show symbol address, etc)"),
+ OPT_END()
+};
+
+int cmd_sched(int argc, const char **argv, const char *prefix __used)
+{
+ symbol__init();
+ page_size = getpagesize();
+
+ argc = parse_options(argc, argv, options, annotate_usage, 0);
+ if (argc) {
+ /*
+ * Special case: if there's an argument left then assume tha
+ * it's a symbol filter:
+ */
+ if (argc > 1)
+ usage_with_options(annotate_usage, options);
+ }
+
+
+ setup_pager();
+
+ return __cmd_sched();
+}