[PATCH] checkstack: print module names

Finding "init_module" high stack usage problems is challenging when there
are over 1600 "init_module" functions in the kernel tree, so make
checkstack.pl print out the filename where the stack usage occurs.  This is
useful for code built as loadable modules.

For built-in code, it just prints the kernel image file name, like
"vmlinux".  Examples:

(before patch:)
0x0000000d callback:					1928
0xffffffff81678c09 huft_build:				1560
0x0018 init_module:					1512

(after patch:)
0x0000000d callback [divacapi]:				1928
0xffffffff81678c09 huft_build [vmlinux]:		1560
0x0018 init_module [hdaps]:				1512

Also change one if-series to use elsif to cut down on unneeded tests.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Joern Engel <joern@wh.fh-wedel.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/scripts/checkstack.pl b/scripts/checkstack.pl
index dadfa20..b349246 100755 (executable)
--- a/scripts/checkstack.pl
+++ b/scripts/checkstack.pl
@@ -89,11 +89,21 @@ sub bysize($) {
 #
 my $funcre = qr/^$x* <(.*)>:$/;
 my $func;
+my $file, $lastslash;
+
 while (my $line = <STDIN>) {
        if ($line =~ m/$funcre/) {
                $func = $1;
        }
-       if ($line =~ m/$re/) {
+       elsif ($line =~ m/(.*):\s*file format/) {
+               $file = $1;
+               $file =~ s/\.ko//;
+               $lastslash = rindex($file, "/");
+               if ($lastslash != -1) {
+                       $file = substr($file, $lastslash + 1);
+               }
+       }
+       elsif ($line =~ m/$re/) {
                my $size = $1;
                $size = hex($size) if ($size =~ /^0x/);
 
@@ -109,7 +119,7 @@ while (my $line = <STDIN>) {
                $addr =~ s/ /0/g;
                $addr = "0x$addr";
 
-               my $intro = "$addr $func:";
+               my $intro = "$addr $func [$file]:";
                my $padlen = 56 - length($intro);
                while ($padlen > 0) {
                        $intro .= '     ';