On Thursday, May 4, 2017 10:31:37 AM CEST Jin Yao wrote:
> perf record -b -g <command>
> perf report --branch-history
>
> This merges the LBRs with the callgraphs.
>
> However it would be nice if it also works without callgraphs (-g)
> set in perf record, so that only the LBRs are displayed.
> But currently perf report errors in this case. For example,
>
> perf record -b <command>
> perf report --branch-history
>
> Error:
> Selected -g or --branch-history but no callchain data. Did
> you call 'perf record' without -g?
>
> This patch displays the LBRs only even if callgraphs(-g) is not
> enabled in perf record.
>
> Signed-off-by: Jin Yao <[email protected]>
> ---
> tools/perf/builtin-report.c | 6 ++++--
> tools/perf/util/callchain.c | 7 ++++---
> tools/perf/util/hist.c | 2 ++
> tools/perf/util/machine.c | 13 ++++++++++++-
> 4 files changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
> index 22478ff..7f82369 100644
> --- a/tools/perf/builtin-report.c
> +++ b/tools/perf/builtin-report.c
> @@ -259,7 +259,8 @@ static int report__setup_sample_type(struct report *rep)
> "'perf record' without -g?\n");
> return -EINVAL;
> }
> - if (symbol_conf.use_callchain) {
> + if (symbol_conf.use_callchain &&
> + !symbol_conf.show_branchflag_count) {
> ui__error("Selected -g or --branch-history but no "
> "callchain data. Did\n"
> "you call 'perf record' without -g?\n");
The `--branch-history` part of this error message is now stale, no?
> @@ -397,7 +398,8 @@ static int perf_evlist__tty_browse_hists(struct
> perf_evlist *evlist,
>
> hists__fprintf_nr_sample_events(hists, rep, evname, stdout);
> hists__fprintf(hists, !quiet, 0, 0, rep->min_percent, stdout,
> - symbol_conf.use_callchain);
> + symbol_conf.use_callchain |
> + symbol_conf.show_branchflag_count);
> fprintf(stdout, "\n\n");
> }
Not sure about the coding style here, but shouldn't this be a boolean or
operator here '||' - semantically? Functionality wise it will be the same, I
guess?
> diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
> index 81fc29a..08d3abf 100644
> --- a/tools/perf/util/callchain.c
> +++ b/tools/perf/util/callchain.c
> @@ -993,11 +993,11 @@ int sample__resolve_callchain(struct perf_sample
> *sample, struct perf_evsel *evsel, struct addr_location *al,
> int max_stack)
> {
> - if (sample->callchain == NULL)
> + if (sample->callchain == NULL && !symbol_conf.show_branchflag_count)
> return 0;
>
> if (symbol_conf.use_callchain || symbol_conf.cumulate_callchain ||
> - perf_hpp_list.parent) {
> + perf_hpp_list.parent || symbol_conf.show_branchflag_count) {
> return thread__resolve_callchain(al->thread, cursor, evsel,
> sample,
> parent, al, max_stack);
> }
> @@ -1006,7 +1006,8 @@ int sample__resolve_callchain(struct perf_sample
> *sample,
>
> int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample
> *sample) {
> - if (!symbol_conf.use_callchain || sample->callchain == NULL)
> + if ((!symbol_conf.use_callchain || sample->callchain == NULL) &&
> + !symbol_conf.show_branchflag_count)
> return 0;
> return callchain_append(he->callchain, &callchain_cursor,
> sample->period);
> }
> diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
> index cf0186a..8b045a5 100644
> --- a/tools/perf/util/hist.c
> +++ b/tools/perf/util/hist.c
> @@ -1762,6 +1762,8 @@ void perf_evsel__output_resort(struct perf_evsel
> *evsel, struct ui_progress *pro else
> use_callchain = symbol_conf.use_callchain;
>
> + use_callchain |= symbol_conf.show_branchflag_count;
> +
> output_resort(evsel__hists(evsel), prog, use_callchain, NULL);
> }
>
> diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
> index a98f55a..792ddcd 100644
> --- a/tools/perf/util/machine.c
> +++ b/tools/perf/util/machine.c
> @@ -1901,13 +1901,16 @@ static int thread__resolve_callchain_sample(struct
> thread *thread, {
> struct branch_stack *branch = sample->branch_stack;
> struct ip_callchain *chain = sample->callchain;
> - int chain_nr = chain->nr;
> + int chain_nr = 0;
> u8 cpumode = PERF_RECORD_MISC_USER;
> int i, j, err, nr_entries;
> int skip_idx = -1;
> int first_call = 0;
> int nr_loop_iter;
>
> + if (chain)
> + chain_nr = chain->nr;
> +
> if (perf_evsel__has_branch_callstack(evsel)) {
> err = resolve_lbr_callchain_sample(thread, cursor, sample,
> parent,
> root_al, max_stack);
> @@ -1945,6 +1948,10 @@ static int thread__resolve_callchain_sample(struct
> thread *thread, for (i = 0; i < nr; i++) {
> if (callchain_param.order == ORDER_CALLEE) {
> be[i] = branch->entries[i];
> +
> + if (chain == NULL)
> + continue;
> +
> /*
> * Check for overlap into the callchain.
> * The return address is one off compared to
> @@ -1998,6 +2005,10 @@ static int thread__resolve_callchain_sample(struct
> thread *thread, if (err)
> return err;
> }
> +
> + if (chain_nr == 0)
> + return 0;
> +
> chain_nr -= nr;
> }
--
Milian Wolff | [email protected] | Software Engineer
KDAB (Deutschland) GmbH&Co KG, a KDAB Group company
Tel: +49-30-521325470
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