Print max memory usage on Linux.

dm/DMReporter.cpp

Index: dm/DMReporter.cpp
diff --git a/dm/DMReporter.cpp b/dm/DMReporter.cpp
index 3f71d693e43a750b98dc348871d4ee228664098e..5187a6f453ae6ab086793756d58e42436d83558a 100644
--- a/dm/DMReporter.cpp
+++ b/dm/DMReporter.cpp
@@ -4,6 +4,17 @@
 #include "SkCommonFlags.h"
 #include "OverwriteLine.h"
 
+#ifdef SK_BUILD_FOR_UNIX
+    #include <sys/resource.h>
+    static long get_max_rss_kb() {
+        struct rusage ru;
+        getrusage(RUSAGE_SELF, &ru);
+        return ru.ru_maxrss;
+    }
+#else
+    static long get_max_rss_kb() { return 0; }
+#endif
+
 namespace DM {
 
 void Reporter::printStatus(SkString name, SkMSec timeMs) const {
@@ -21,7 +32,10 @@ void Reporter::printStatus(SkString name, SkMSec timeMs) const {
         status.appendf(", %d failed", failed);
     }
     if (FLAGS_verbose) {
-        status.appendf("\t%5dms %s", timeMs, name.c_str());
+        if (long max_rss_kb = get_max_rss_kb()) {
+            status.appendf("\t%4ldM peak", max_rss_kb / 1024);
+        }
+        status.appendf("\t%5dms\t%s", timeMs, name.c_str());
     }
     SkDebugf("%s", status.c_str());
 }