perf annotate browser: Align jump labels

Find out at browser startup the max width and use it when rendering jump
labels on the screen.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-7dxjiwqb77wz6f5lc05e0i0x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 12 insertions, 0 deletions

diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 8109a907841e..d03599fbe78b 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -148,3 +148,13 @@ int readn(int fd, void *buf, size_t n)
 
         return buf - buf_start;
 }
+
+size_t hex_width(u64 v)
+{
+        size_t n = 1;
+
+        while ((v >>= 4))
+                ++n;
+
+        return n;
+}
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 0f99f394d8e0..6121e24fefc0 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -265,4 +265,6 @@ bool is_power_of_2(unsigned long n)
         return (n != 0 && ((n & (n - 1)) == 0));
 }
 
+size_t hex_width(u64 v);
+
 #endif