perf diff: Add -F option to display formula for computation

Adding -F option to display the formula for specified computation.

This is mainly to facilitate debugging, but can be useful anyway.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1349448287-18919-7-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Documentation/perf-diff.txt b/tools/perf/Documentation/perf-diff.txt
index 21cc2ef..194f37d 100644 (file)
--- a/tools/perf/Documentation/perf-diff.txt
+++ b/tools/perf/Documentation/perf-diff.txt
@@ -87,6 +87,10 @@ OPTIONS
 --period::
         Show period values for both compared hist entries.
 
+-F::
+--formula::
+        Show formula for given computation.
+
 COMPARISON METHODS
 ------------------
 delta

diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c
index 2411dd1..dd9c064 100644 (file)
--- a/tools/perf/builtin-diff.c
+++ b/tools/perf/builtin-diff.c
@@ -25,6 +25,7 @@ static char     diff__default_sort_order[] = "dso,symbol";
 static bool  force;
 static bool show_displacement;
 static bool show_period;
+static bool show_formula;
 static bool show_baseline_only;
 static bool sort_compute;
 
@@ -190,6 +191,62 @@ s64 perf_diff__compute_wdiff(struct hist_entry *he)
        return he->diff.wdiff;
 }
 
+static int formula_delta(struct hist_entry *he, char *buf, size_t size)
+{
+       struct hist_entry *pair = he->pair;
+
+       if (!pair)
+               return -1;
+
+       return scnprintf(buf, size,
+                        "(%" PRIu64 " * 100 / %" PRIu64 ") - "
+                        "(%" PRIu64 " * 100 / %" PRIu64 ")",
+                         he->stat.period, he->hists->stats.total_period,
+                         pair->stat.period, pair->hists->stats.total_period);
+}
+
+static int formula_ratio(struct hist_entry *he, char *buf, size_t size)
+{
+       struct hist_entry *pair = he->pair;
+       double new_period = he->stat.period;
+       double old_period = pair ? pair->stat.period : 0;
+
+       if (!pair)
+               return -1;
+
+       return scnprintf(buf, size, "%.0F / %.0F", new_period, old_period);
+}
+
+static int formula_wdiff(struct hist_entry *he, char *buf, size_t size)
+{
+       struct hist_entry *pair = he->pair;
+       u64 new_period = he->stat.period;
+       u64 old_period = pair ? pair->stat.period : 0;
+
+       if (!pair)
+               return -1;
+
+       return scnprintf(buf, size,
+                 "(%" PRIu64 " * " "%" PRId64 ") - (%" PRIu64 " * " "%" PRId64 ")",
+                 new_period, compute_wdiff_w2, old_period, compute_wdiff_w1);
+}
+
+int perf_diff__formula(char *buf, size_t size, struct hist_entry *he)
+{
+       switch (compute) {
+       case COMPUTE_DELTA:
+               return formula_delta(he, buf, size);
+       case COMPUTE_RATIO:
+               return formula_ratio(he, buf, size);
+       case COMPUTE_WEIGHTED_DIFF:
+               return formula_wdiff(he, buf, size);
+       default:
+               BUG_ON(1);
+       }
+
+       return -1;
+}
+
 static int hists__add_entry(struct hists *self,
                            struct addr_location *al, u64 period)
 {
@@ -543,6 +600,8 @@ static const struct option options[] = {
                     setup_compute),
        OPT_BOOLEAN('p', "period", &show_period,
                    "Show period values."),
+       OPT_BOOLEAN('F', "formula", &show_formula,
+                   "Show formula."),
        OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
                    "dump raw trace in ASCII"),
        OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
@@ -571,7 +630,10 @@ static void ui_init(void)
        /* No overhead column. */
        perf_hpp__column_enable(PERF_HPP__OVERHEAD, false);
 
-       /* Display baseline/delta/ratio/displacement/periods columns. */
+       /*
+        * Display baseline/delta/ratio/displacement/
+        * formula/periods columns.
+        */
        perf_hpp__column_enable(PERF_HPP__BASELINE, true);
 
        switch (compute) {
@@ -591,6 +653,9 @@ static void ui_init(void)
        if (show_displacement)
                perf_hpp__column_enable(PERF_HPP__DISPL, true);
 
+       if (show_formula)
+               perf_hpp__column_enable(PERF_HPP__FORMULA, true);
+
        if (show_period) {
                perf_hpp__column_enable(PERF_HPP__PERIOD, true);
                perf_hpp__column_enable(PERF_HPP__PERIOD_BASELINE, true);

diff --git a/tools/perf/ui/hist.c b/tools/perf/ui/hist.c
index 2fadaff..305eb79 100644 (file)
--- a/tools/perf/ui/hist.c
+++ b/tools/perf/ui/hist.c
@@ -359,6 +359,27 @@ static int hpp__entry_displ(struct perf_hpp *hpp,
        return scnprintf(hpp->buf, hpp->size, fmt, buf);
 }
 
+static int hpp__header_formula(struct perf_hpp *hpp)
+{
+       const char *fmt = symbol_conf.field_sep ? "%s" : "%70s";
+
+       return scnprintf(hpp->buf, hpp->size, fmt, "Formula");
+}
+
+static int hpp__width_formula(struct perf_hpp *hpp __maybe_unused)
+{
+       return 70;
+}
+
+static int hpp__entry_formula(struct perf_hpp *hpp, struct hist_entry *he)
+{
+       const char *fmt = symbol_conf.field_sep ? "%s" : "%-70s";
+       char buf[96] = " ";
+
+       perf_diff__formula(buf, sizeof(buf), he);
+       return scnprintf(hpp->buf, hpp->size, fmt, buf);
+}
+
 #define HPP__COLOR_PRINT_FNS(_name)            \
        .header = hpp__header_ ## _name,                \
        .width  = hpp__width_ ## _name,         \
@@ -383,7 +404,8 @@ struct perf_hpp_fmt perf_hpp__format[] = {
        { .cond = false, HPP__PRINT_FNS(delta) },
        { .cond = false, HPP__PRINT_FNS(ratio) },
        { .cond = false, HPP__PRINT_FNS(wdiff) },
-       { .cond = false, HPP__PRINT_FNS(displ) }
+       { .cond = false, HPP__PRINT_FNS(displ) },
+       { .cond = false, HPP__PRINT_FNS(formula) }
 };
 
 #undef HPP__COLOR_PRINT_FNS

diff --git a/tools/perf/ui/stdio/hist.c b/tools/perf/ui/stdio/hist.c
index fbd4e32..f0ee204 100644 (file)
--- a/tools/perf/ui/stdio/hist.c
+++ b/tools/perf/ui/stdio/hist.c
@@ -342,7 +342,7 @@ size_t hists__fprintf(struct hists *hists, bool show_header, int max_rows,
        const char *sep = symbol_conf.field_sep;
        const char *col_width = symbol_conf.col_width_list_str;
        int idx, nr_rows = 0;
-       char bf[64];
+       char bf[96];
        struct perf_hpp dummy_hpp = {
                .buf    = bf,
                .size   = sizeof(bf),

diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index 5604791..c751624 100644 (file)
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -145,6 +145,7 @@ enum {
        PERF_HPP__RATIO,
        PERF_HPP__WEIGHTED_DIFF,
        PERF_HPP__DISPL,
+       PERF_HPP__FORMULA,
 
        PERF_HPP__MAX_INDEX
 };
@@ -210,4 +211,5 @@ unsigned int hists__sort_list_width(struct hists *self);
 double perf_diff__compute_delta(struct hist_entry *he);
 double perf_diff__compute_ratio(struct hist_entry *he);
 s64 perf_diff__compute_wdiff(struct hist_entry *he);
+int perf_diff__formula(char *buf, size_t size, struct hist_entry *he);
 #endif /* __PERF_HIST_H */