linux-kernel - [PATCH v1] bloat-o-meter: Don't fail with division by 0

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Date:   Thu, 23 Nov 2017 19:12:19 +0200
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Andrew Morton <akpm@...ux-foundation.org>,
        Alexey Dobriyan <adobriyan@...il.com>,
        Vaneet Narang <v.narang@...sung.com>,
        linux-kernel@...r.kernel.org
Cc:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Subject: [PATCH v1] bloat-o-meter: Don't fail with division by 0

Under some circumstances it's possible to get a divider 0 which crashes
the script.

Traceback (most recent call last):
  File "linux/scripts/bloat-o-meter", line 98, in <module>
    print_result("Function", "tTdDbBrR", 2)
  File "linux/scripts/bloat-o-meter", line 87, in print_result
    (otot, ntot, (ntot - otot)*100.0/otot))
ZeroDivisionError: float division by zero

Hide this by checking the divider first.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 scripts/bloat-o-meter | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/scripts/bloat-o-meter b/scripts/bloat-o-meter
index 6f099f915dcf..94b664817ad9 100755
--- a/scripts/bloat-o-meter
+++ b/scripts/bloat-o-meter
@@ -83,8 +83,11 @@ def print_result(symboltype, symbolformat, argc):
     for d, n in delta:
         if d: print("%-40s %7s %7s %+7d" % (n, old.get(n,"-"), new.get(n,"-"), d))
 
-    print("Total: Before=%d, After=%d, chg %+.2f%%" % \
-        (otot, ntot, (ntot - otot)*100.0/otot))
+    if otot:
+        percent = (ntot - otot) * 100.0 / otot
+    else:
+        percent = 0
+    print("Total: Before=%d, After=%d, chg %+.2f%%" % (otot, ntot, percent))
 
 if sys.argv[1] == "-c":
     print_result("Function", "tT", 3)
-- 
2.15.0