tracing: Add regex for weak functions in recordmcount.pl

Add a variable to contain the regex needed to find weak functions
in the 'nm' output. This will allow other archs to easily override it.

Also rename the regex variable $nm_regex to $local_regex to be more
descriptive.

Signed-off-by: Li Hong <lihong.hi@gmail.com>
LKML-Reference: <20091028050619.GF30758@uhli>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

scripts/recordmcount.pl

@@ -92,7 +92,7 @@
 #
 # Here are the steps we take:
 #
-# 1) Record all the local symbols by using 'nm'
+# 1) Record all the local and weak symbols by using 'nm'
 # 2) Use objdump to find all the call site offsets and sections for
 #    mcount.
 # 3) Compile the list into its own object.
@@ -152,7 +152,8 @@
 my %convert;		# List of local functions used that needs conversion
 
 my $type;
-my $nm_regex;		# Find the local functions (return function)
+my $local_regex;	# Match a local function (return function)
+my $weak_regex; 	# Match a weak function (return function)
 my $section_regex;	# Find the start of a section
 my $function_regex;	# Find the name of a function
 			#    (return offset and func name)
@@ -197,7 +198,8 @@ sub check_objcopy
 # We base the defaults off of i386, the other archs may
 # feel free to change them in the below if statements.
 #
-$nm_regex = "^[0-9a-fA-F]+\\s+t\\s+(\\S+)";
+$local_regex = "^[0-9a-fA-F]+\\s+t\\s+(\\S+)";
+$weak_regex = "^[0-9a-fA-F]+\\s+([wW])\\s+(\\S+)";
 $section_regex = "Disassembly of section\\s+(\\S+):";
 $function_regex = "^([0-9a-fA-F]+)\\s+<(.*?)>:";
 $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\smcount\$";
@@ -246,7 +248,7 @@ sub check_objcopy
     $cc .= " -m32";
 
 } elsif ($arch eq "powerpc") {
-    $nm_regex = "^[0-9a-fA-F]+\\s+t\\s+(\\.?\\S+)";
+    $local_regex = "^[0-9a-fA-F]+\\s+t\\s+(\\.?\\S+)";
     $function_regex = "^([0-9a-fA-F]+)\\s+<(\\.?.*?)>:";
     $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s\\.?_mcount\$";
 
@@ -322,13 +324,13 @@ sub check_objcopy
 
 #
 # Step 1: find all the local (static functions) and weak symbols.
-#        't' is local, 'w/W' is weak (we never use a weak function)
+#         't' is local, 'w/W' is weak
 #
 open (IN, "$nm $inputfile|") || die "error running $nm";
 while (<IN>) {
-    if (/$nm_regex/) {
+    if (/$local_regex/) {
 	$locals{$1} = 1;
-    } elsif (/^[0-9a-fA-F]+\s+([wW])\s+(\S+)/) {
+    } elsif (/$weak_regex/) {
 	$weak{$2} = $1;
     }
 }