perf report: Add --branch-history option

Add a --branch-history option to perf report that changes all the
settings necessary for using the branches in callstacks.

This is just a short cut to make this nicer to use, it does not enable
any functionality by itself.

v2: Change sort order. Rename option to --branch-history to
    be less confusing.
v3: Updates
v4: Fix conflict with newer perf base
v5: Port to latest tip
v6: Add more comments. Remove CCKEY_ADDRESS setting. Remove
    unnecessary branch_mode setting. Use a boolean.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1415844328-4884-5-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 27 insertions, 4 deletions

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index 22706beffabc..dd7cccdde498 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -271,6 +271,11 @@ OPTIONS
         branch stacks and it will automatically switch to the branch view mode,
         unless --no-branch-stack is used.
 
+--branch-history::
+        Add the addresses of sampled taken branches to the callstack.
+        This allows to examine the path the program took to each sample.
+        The data collection must have used -b (or -j) and -g.
+
 --objdump=<path>::
         Path to objdump binary.
 
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 410d44fac64f..fb272ff435c9 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -226,8 +226,9 @@ static int report__setup_sample_type(struct report *rep)
                         return -EINVAL;
                 }
                 if (symbol_conf.use_callchain) {
-                        ui__error("Selected -g but no callchain data. Did "
-                                    "you call 'perf record' without -g?\n");
+                        ui__error("Selected -g or --branch-history but no "
+                                  "callchain data. Did\n"
+                                  "you call 'perf record' without -g?\n");
                         return -1;
                 }
         } else if (!rep->dont_use_callchains &&
@@ -575,6 +576,7 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
         struct stat st;
         bool has_br_stack = false;
         int branch_mode = -1;
+        bool branch_call_mode = false;
         char callchain_default_opt[] = "fractal,0.5,callee";
         const char * const report_usage[] = {
                 "perf report [<options>]",
@@ -684,7 +686,10 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
         OPT_BOOLEAN(0, "group", &symbol_conf.event_group,
                     "Show event group information together"),
         OPT_CALLBACK_NOOPT('b', "branch-stack", &branch_mode, "",
-                    "use branch records for histogram filling", parse_branch_mode),
+                    "use branch records for per branch histogram filling",
+                    parse_branch_mode),
+        OPT_BOOLEAN(0, "branch-history", &branch_call_mode,
+                    "add last branch records to call history"),
         OPT_STRING(0, "objdump", &objdump_path, "path",
                    "objdump binary to use for disassembly and annotations"),
         OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
@@ -745,10 +750,23 @@ repeat:
         has_br_stack = perf_header__has_feat(&session->header,
                                              HEADER_BRANCH_STACK);
 
-        if ((branch_mode == -1 && has_br_stack) || branch_mode == 1) {
+        /*
+         * Branch mode is a tristate:
+         * -1 means default, so decide based on the file having branch data.
+         * 0/1 means the user chose a mode.
+         */
+        if (((branch_mode == -1 && has_br_stack) || branch_mode == 1) &&
+            branch_call_mode == -1) {
                 sort__mode = SORT_MODE__BRANCH;
                 symbol_conf.cumulate_callchain = false;
         }
+        if (branch_call_mode) {
+                callchain_param.branch_callstack = 1;
+                symbol_conf.use_callchain = true;
+                callchain_register_param(&callchain_param);
+                if (sort_order == NULL)
+                        sort_order = "srcline,symbol,dso";
+        }
 
         if (report.mem_mode) {
                 if (sort__mode == SORT_MODE__BRANCH) {