Use --show-percs with Cachegrind and Callgrind.

Author: nnethercote

collector/README.md

@@ -244,7 +244,7 @@ except that `$PROFILER` is one of the following.
     often results in success.
 - `cachegrind`: Profile with
   [Cachegrind](http://valgrind.org/docs/manual/cg-manual.html), a tracing
-  profiler.
+  profiler. Requires Valgrind 3.15 or later.
   - **Purpose**. Cachegrind provides global, per-function, and per-source-line
     instruction counts. This fine-grained information can be extremely useful.
     Cachegrind's results are almost deterministic, which eases comparisons
@@ -263,7 +263,7 @@ except that `$PROFILER` is one of the following.
     `--mod-filename='s/rust[01]/rustN/g'` to eliminate path differences.
 - `callgrind`: Profile with
     [Callgrind](http://valgrind.org/docs/manual/cl-manual.html), a tracing
-    profiler.
+    profiler. Requires Valgrind 3.15 or later.
   - **Purpose**. Callgrind collects the same information as Cachegrind, plus
     function call information. So it can be used like either Cachegrind or
     `perf-record`. However, it cannot perform diffs between profiles.

collector/src/bin/rustc-perf-collector/execute.rs

@@ -577,7 +577,10 @@ impl<'a> Processor for ProfileProcessor<'a> {
                 fs::copy(&tmp_cgout_file, &cgout_file)?;
 
                 let mut cg_annotate_cmd = Command::new("cg_annotate");
-                cg_annotate_cmd.arg("--auto=yes").arg(&cgout_file);
+                cg_annotate_cmd
+                    .arg("--auto=yes")
+                    .arg("--show-percs=yes")
+                    .arg(&cgout_file);
                 let output = cg_annotate_cmd.output()?;
 
                 fs::write(cgann_file, &output.stdout)?;
@@ -595,7 +598,10 @@ impl<'a> Processor for ProfileProcessor<'a> {
                 fs::copy(&tmp_clgout_file, &clgout_file)?;
 
                 let mut clg_annotate_cmd = Command::new("callgrind_annotate");
-                clg_annotate_cmd.arg("--auto=yes").arg(&clgout_file);
+                clg_annotate_cmd
+                    .arg("--auto=yes")
+                    .arg("--show-percs=yes")
+                    .arg(&clgout_file);
                 let output = clg_annotate_cmd.output()?;
 
                 fs::write(clgann_file, &output.stdout)?;