scripts/decode_stacktrace.sh: handle symbols in modules

scripts/decode_stacktrace.sh presently displays module symbols as

	func+0x0ff/0x5153 [module]

Add a third argument: the pathname of a directory where the script
should look for the file module.ko so that the output appears as

	func (foo/bar.c:123) module

Without the argument or if the module file isn't found the script prints
such symbols as is without decoding.

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh
index 00d6d53c2681dac3ce2f736baff7cbc177825b0e..c332684e1b5ace1e4ea8a357ed83b5931e04cdfd 100755 (executable)
--- a/scripts/decode_stacktrace.sh
+++ b/scripts/decode_stacktrace.sh
@@ -2,15 +2,17 @@
 # (c) 2014, Sasha Levin <sasha.levin@oracle.com>
 #set -x
 
-if [[ $# != 2 ]]; then
+if [[ $# < 2 ]]; then
        echo "Usage:"
-       echo "  $0 [vmlinux] [base path]"
+       echo "  $0 [vmlinux] [base path] [modules path]"
        exit 1
 fi
 
 vmlinux=$1
 basepath=$2
+modpath=$3
 declare -A cache
+declare -A modcache
 
 parse_symbol() {
        # The structure of symbol at this point is:
@@ -19,6 +21,17 @@ parse_symbol() {
        # For example:
        #   do_basic_setup+0x9c/0xbf
 
+       if [[ $module == "" ]] ; then
+               local objfile=$vmlinux
+       elif [[ "${modcache[$module]+isset}" == "isset" ]]; then
+               local objfile=${modcache[$module]}
+       else
+               [[ $modpath == "" ]] && return
+               local objfile=$(find "$modpath" -name $module.ko -print -quit)
+               [[ $objfile == "" ]] && return
+               modcache[$module]=$objfile
+       fi
+
        # Remove the englobing parenthesis
        symbol=${symbol#\(}
        symbol=${symbol%\)}
@@ -29,11 +42,11 @@ parse_symbol() {
        # Use 'nm vmlinux' to figure out the base address of said symbol.
        # It's actually faster to call it every time than to load it
        # all into bash.
-       if [[ "${cache[$name]+isset}" == "isset" ]]; then
-               local base_addr=${cache[$name]}
+       if [[ "${cache[$module,$name]+isset}" == "isset" ]]; then
+               local base_addr=${cache[$module,$name]}
        else
-               local base_addr=$(nm "$vmlinux" | grep -i ' t ' | awk "/ $name\$/ {print \$1}" | head -n1)
-               cache["$name"]="$base_addr"
+               local base_addr=$(nm "$objfile" | grep -i ' t ' | awk "/ $name\$/ {print \$1}" | head -n1)
+               cache[$module,$name]="$base_addr"
        fi
        # Let's start doing the math to get the exact address into the
        # symbol. First, strip out the symbol total length.
@@ -48,12 +61,12 @@ parse_symbol() {
        local address=$(printf "%x\n" "$expr")
 
        # Pass it to addr2line to get filename and line number
-        # Could get more than one result
-       if [[ "${cache[$address]+isset}" == "isset" ]]; then
-               local code=${cache[$address]}
+       # Could get more than one result
+       if [[ "${cache[$module,$address]+isset}" == "isset" ]]; then
+               local code=${cache[$module,$address]}
        else
-               local code=$(addr2line -i -e "$vmlinux" "$address")
-               cache[$address]=$code
+               local code=$(addr2line -i -e "$objfile" "$address")
+               cache[$module,$address]=$code
        fi
 
        # addr2line doesn't return a proper error code if it fails, so
@@ -105,13 +118,23 @@ handle_line() {
                fi
        done
 
-       # The symbol is the last element, process it
-       symbol=${words[$last]}
+       if [[ ${words[$last]} =~ \[([^]]+)\] ]]; then
+               module=${words[$last]}
+               module=${module#\[}
+               module=${module%\]}
+               symbol=${words[$last-1]}
+               unset words[$last-1]
+       else
+               # The symbol is the last element, process it
+               symbol=${words[$last]}
+               module=
+       fi
+
        unset words[$last]
        parse_symbol # modifies $symbol
 
        # Add up the line number to the symbol
-       echo "${words[@]}" "$symbol"
+       echo "${words[@]}" "$symbol $module"
 }
 
 while read line; do
@@ -121,8 +144,8 @@ while read line; do
                handle_line "$line"
        # Is it a code line?
        elif [[ $line == *Code:* ]]; then
-                decode_code "$line"
-        else
+               decode_code "$line"
+       else
                # Nothing special in this line, show it as is
                echo "$line"
        fi