perf top: Add callgraph support

Just like in 'perf report', but live.

Still needs to decay the callchains, but already somewhat useful as-is.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-cj3rmaf5jpsvi3v0tf7t4uvp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 144 insertions, 2 deletions

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 2cf5e50a6997..b9b7fe085895 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -76,6 +76,12 @@ static bool			system_wide			=  false;
 
 static bool                     use_tui, use_stdio;
 
+static bool                     sort_has_symbols;
+
+static bool                     dont_use_callchains;
+static char                     callchain_default_opt[]         = "fractal,0.5,callee";
+
+
 static int                      default_interval                =      0;
 
 static bool                     kptr_restrict_warned;
@@ -648,9 +654,11 @@ static void perf_event__process_sample(const union perf_event *event,
                                        struct perf_sample *sample,
                                        struct perf_session *session)
 {
+        struct symbol *parent = NULL;
         u64 ip = event->ip.ip;
         struct addr_location al;
         struct machine *machine;
+        int err;
         u8 origin = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
 
         ++top.samples;
@@ -748,13 +756,29 @@ static void perf_event__process_sample(const union perf_event *event,
                 evsel = perf_evlist__id2evsel(top.evlist, sample->id);
                 assert(evsel != NULL);
 
+                if ((sort__has_parent || symbol_conf.use_callchain) &&
+                    sample->callchain) {
+                        err = perf_session__resolve_callchain(session, al.thread,
+                                                              sample->callchain, &parent);
+                        if (err)
+                                return;
+                }
+
                 he = perf_session__add_hist_entry(session, &al, sample, evsel);
                 if (he == NULL) {
                         pr_err("Problem incrementing symbol period, skipping event\n");
                         return;
                 }
 
-                record_precise_ip(he, evsel->idx, ip);
+                if (symbol_conf.use_callchain) {
+                        err = callchain_append(he->callchain, &session->callchain_cursor,
+                                               sample->period);
+                        if (err)
+                                return;
+                }
+
+                if (sort_has_symbols)
+                        record_precise_ip(he, evsel->idx, ip);
         }
 
         return;
@@ -808,6 +832,9 @@ static void start_counters(struct perf_evlist *evlist)
                         attr->read_format |= PERF_FORMAT_ID;
                 }
 
+                if (symbol_conf.use_callchain)
+                        attr->sample_type |= PERF_SAMPLE_CALLCHAIN;
+
                 attr->mmap = 1;
                 attr->comm = 1;
                 attr->inherit = inherit;
@@ -864,10 +891,27 @@ out_err:
         exit(0);
 }
 
+static int setup_sample_type(void)
+{
+        if (!sort_has_symbols) {
+                if (symbol_conf.use_callchain) {
+                        ui__warning("Selected -g but \"sym\" not present in --sort/-s.");
+                        return -EINVAL;
+                }
+        } else if (!dont_use_callchains && callchain_param.mode != CHAIN_NONE) {
+                if (callchain_register_param(&callchain_param) < 0) {
+                        ui__warning("Can't register callchain params.\n");
+                        return -EINVAL;
+                }
+        }
+
+        return 0;
+}
+
 static int __cmd_top(void)
 {
         pthread_t thread;
-        int ret __used;
+        int ret;
         /*
          * FIXME: perf_session__new should allow passing a O_MMAP, so that all this
          * mmap reading, etc is encapsulated in it. Use O_WRONLY for now.
@@ -876,6 +920,10 @@ static int __cmd_top(void)
         if (top.session == NULL)
                 return -ENOMEM;
 
+        ret = setup_sample_type();
+        if (ret)
+                goto out_delete;
+
         if (top.target_tid != -1)
                 perf_event__synthesize_thread_map(top.evlist->threads,
                                                   perf_event__process, top.session);
@@ -916,6 +964,90 @@ static int __cmd_top(void)
                         ret = poll(top.evlist->pollfd, top.evlist->nr_fds, 100);
         }
 
+out_delete:
+        perf_session__delete(top.session);
+        top.session = NULL;
+
+        return 0;
+}
+
+static int
+parse_callchain_opt(const struct option *opt __used, const char *arg,
+                    int unset)
+{
+        char *tok, *tok2;
+        char *endptr;
+
+        /*
+         * --no-call-graph
+         */
+        if (unset) {
+                dont_use_callchains = true;
+                return 0;
+        }
+
+        symbol_conf.use_callchain = true;
+
+        if (!arg)
+                return 0;
+
+        tok = strtok((char *)arg, ",");
+        if (!tok)
+                return -1;
+
+        /* get the output mode */
+        if (!strncmp(tok, "graph", strlen(arg)))
+                callchain_param.mode = CHAIN_GRAPH_ABS;
+
+        else if (!strncmp(tok, "flat", strlen(arg)))
+                callchain_param.mode = CHAIN_FLAT;
+
+        else if (!strncmp(tok, "fractal", strlen(arg)))
+                callchain_param.mode = CHAIN_GRAPH_REL;
+
+        else if (!strncmp(tok, "none", strlen(arg))) {
+                callchain_param.mode = CHAIN_NONE;
+                symbol_conf.use_callchain = false;
+
+                return 0;
+        }
+
+        else
+                return -1;
+
+        /* get the min percentage */
+        tok = strtok(NULL, ",");
+        if (!tok)
+                goto setup;
+
+        callchain_param.min_percent = strtod(tok, &endptr);
+        if (tok == endptr)
+                return -1;
+
+        /* get the print limit */
+        tok2 = strtok(NULL, ",");
+        if (!tok2)
+                goto setup;
+
+        if (tok2[0] != 'c') {
+                callchain_param.print_limit = strtod(tok2, &endptr);
+                tok2 = strtok(NULL, ",");
+                if (!tok2)
+                        goto setup;
+        }
+
+        /* get the call chain order */
+        if (!strcmp(tok2, "caller"))
+                callchain_param.order = ORDER_CALLER;
+        else if (!strcmp(tok2, "callee"))
+                callchain_param.order = ORDER_CALLEE;
+        else
+                return -1;
+setup:
+        if (callchain_register_param(&callchain_param) < 0) {
+                fprintf(stderr, "Can't register callchain params\n");
+                return -1;
+        }
         return 0;
 }
 
@@ -973,6 +1105,10 @@ static const struct option options[] = {
                    "sort by key(s): pid, comm, dso, symbol, parent"),
         OPT_BOOLEAN('n', "show-nr-samples", &symbol_conf.show_nr_samples,
                     "Show a column with the number of samples"),
+        OPT_CALLBACK_DEFAULT('G', "call-graph", NULL, "output_type,min_percent, call_order",
+                     "Display callchains using output_type (graph, flat, fractal, or none), min percent threshold and callchain order. "
+                     "Default: fractal,0.5,callee", &parse_callchain_opt,
+                     callchain_default_opt),
         OPT_BOOLEAN(0, "show-total-period", &symbol_conf.show_total_period,
                     "Show a column with the sum of periods"),
         OPT_STRING(0, "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
@@ -1082,6 +1218,12 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
         sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", stdout);
         sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", stdout);
 
+        /*
+         * Avoid annotation data structures overhead when symbols aren't on the
+         * sort list.
+         */
+        sort_has_symbols = sort_sym.list.next != NULL;
+
         get_term_dimensions(&winsize);
         if (top.print_entries == 0) {
                 update_print_entries(&winsize);