On 8/22/12 8:37 AM, chenggang qin wrote: > From: Chenggang Qin <[email protected]> > > While we use "perf top -p 'pid'" to monitor the symbols of specified > processes, some new threads would be created by the monitored processes > during "perf top" is running. In current version, these new threads and > their symbols cannot be shown. > This patch add ability to show these new threads. > > Signed-off-by: Chenggang Qin <[email protected]> > > --- > tools/perf/builtin-top.c | 86 > ++++++++++++++++++++++++++++++++++++++++++++-- > tools/perf/util/evlist.c | 2 ++ > 2 files changed, 85 insertions(+), 3 deletions(-) > > diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c > index 68cd61e..54c9cc1 100644 > --- a/tools/perf/builtin-top.c > +++ b/tools/perf/builtin-top.c > @@ -882,7 +882,7 @@ static void perf_top__mmap_read(struct perf_top *top) > perf_top__mmap_read_idx(top, i); > } > > -static void perf_top__start_counters(struct perf_top *top) > +static int perf_top__start_counters(struct perf_top *top) > { > struct perf_evsel *counter, *first; > struct perf_evlist *evlist = top->evlist; > @@ -929,6 +929,10 @@ try_again: > group_fd) < 0) { > int err = errno; > > + if (err == ESRCH) { > + return err; > + } > + > if (err == EPERM || err == EACCES) { > ui__error_paranoid(); > goto out_err; > @@ -994,7 +998,7 @@ try_again: > goto out_err; > } > > - return; > + return 0; > > out_err: > exit_browser(0); > @@ -1018,6 +1022,77 @@ static int perf_top__setup_sample_type(struct perf_top > *top) > return 0; > } > > +static int thread_map_cmp(struct thread_map *threads_a, > + struct thread_map *threads_b) > +{ > + int i, j; > + > + if (threads_a->nr != threads_b->nr) { > + return 1; > + } else { > + for (i = 0; i < threads_b->nr; i++) { > + for (j = 0; j < threads_a->nr; j++) > + if (threads_b->map[i] == threads_a->map[j]) > + break; > + > + if (j == threads_a->nr) > + return 1; > + } > + > + return 0; > + } > +} > + > +static void check_new_threads(struct perf_top *top) > +{ > + struct thread_map *new_thread_map; > + struct perf_evsel *counter; > + struct perf_evlist *evlist = top->evlist; > + > +retry: > + new_thread_map = thread_map__new_str(top->target.pid, top->target.tid, > + top->target.uid); > + if (!new_thread_map) > + return; > + > + if (thread_map_cmp(top->evlist->threads, new_thread_map) == 0) { > + free(new_thread_map); > + return; > + } else { > + list_for_each_entry(counter, &evlist->entries, node) { > + perf_evsel__close(counter, top->evlist->cpus->nr, > + top->evlist->threads->nr); > + } > + > + if (top->evlist->mmap) > + perf_evlist__munmap(top->evlist); > + > + if (top->evlist->pollfd) { > + free(top->evlist->pollfd); > + top->evlist->pollfd = NULL; > + } > + > + top->evlist->nr_fds = 0; > + > + thread_map__delete(top->evlist->threads); > + top->evlist->threads = new_thread_map; > + > + if (perf_top__start_counters(top) == ESRCH) { > + while (thread_map_cmp(top->evlist->threads, > + new_thread_map) == 0) { > + new_thread_map = > thread_map__new_str(top->target.pid, > + > top->target.tid, > + > top->target.uid); > + if (!new_thread_map) > + return; > + } > + goto retry; > + } > + > + return; > + } > +} > +
I think it would be better to respond to FORK (and EXIT) events and open (close) counters accordingly. perf-top gets events when a thread is created or terminated; it might as well use the events to react than to poll every trip through the loop. David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
