lkml.org 
[lkml]   [2011]   [Oct]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 2/3] ARM: Add static kernel function stack size analyzer, for ARM
This tool can be used to analyze the function stack size for ARM kernels,
statically, based on a disassembly of vmlinux (or an individual .o file

Signed-off-by: Tim Bird <tim.bird@am.sony.com>
---
scripts/stack_size | 289 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 289 insertions(+), 0 deletions(-)
create mode 100755 scripts/stack_size
diff --git a/scripts/stack_size b/scripts/stack_size
new file mode 100755
index 0000000..af9fdac
--- /dev/null
+++ b/scripts/stack_size
@@ -0,0 +1,289 @@
+#!/usr/bin/python
+# stack_size - a program to parse ARM assembly files and produce
+# a listing of stack sizes for the functions encountered.
+#
+# To use: compile your kernel as normal, then run this program on vmlinux:
+# $ scripts/stac_size vmlinux
+#
+# If you have cross-compiled, then your CROSS_COMPILE environment variable
+# should be set to the cross prefix for your toolchain
+#
+# Author: Tim Bird <tim dot bird ~(at)~ am dot sony dot com>
+# Copyright 2011 Sony Network Entertainment, Inc
+#
+# GPL version 2.0 applies.
+#
+
+import os, sys
+version = "1.0"
+
+debug = 0
+
+def dprint(msg):
+ global debug
+ if debug:
+ print msg
+
+def usage():
+ print """Usage: %s [options] <filename>
+
+Show stack size for functions in a program or object file.
+Generate and parse the ARM assembly for the indicated filename,
+and print out the size of the stack for each function.
+
+If you used a cross-compiler, please set the cross-compiler prefix
+in the environment variable 'CROSS_COMPILE', before using this tool.
+
+Options:
+ -h show this usage help
+ -t <n> show the top n functions with the largest stacks
+ (default is to show top 10 functions with largest stacks)
+ -f show full function list
+ -g show histogram of stack depths
+ -V or --version show version information and exit
+
+Notes: This leaves the assembly file in the same directory as the source
+filename, called '<filename>.S' This program currently only supports
+ARM EABI.
+
+""" % os.path.basename(sys.argv[0])
+ sys.exit(0)
+
+class function_class():
+ def __init__(self, name, addr):
+ self.name = name
+ self.addr = addr
+ self.depth = 0
+
+ def __repr__(self):
+ return "function: %s with depth %d" % (self.name, self.depth)
+
+def open_assembly(filename):
+ base = filename
+ if base.endswith(".o"):
+ base = base[:-2]
+
+ assembly_filename = "%s.S" % base
+
+ try:
+ fd = open(assembly_filename)
+ except:
+ print "Could not find %s - trying to generate from %s\n" % \
+ (assembly_filename, filename)
+ print "This might take a few minutes..."
+ try:
+ cross = os.environ["CROSS_COMPILE"]
+ except:
+ cross = ""
+ cmd = "%sobjdump -d %s >%s" % \
+ (cross, filename, assembly_filename)
+ print "Using command: '%s'" % cmd
+ os.system(cmd)
+
+ try:
+ fd = open(assembly_filename)
+ except:
+ print "Could not find %s, and conversion didn't work\n" % \
+ (assembly_filename)
+ sys.exit(1)
+
+ return fd;
+
+def do_show_histogram(functions):
+ depth_count = {}
+
+ max_depth_bucket = 0
+ for funcname in functions.keys():
+ depth = functions[funcname].depth
+ depth_bucket = depth/10
+ if depth_bucket > max_depth_bucket:
+ max_depth_bucket = depth_bucket
+
+ try:
+ depth_count[depth_bucket] += 1
+ except:
+ depth_count[depth_bucket] = 1
+
+ print "=========== HISTOGRAM =============="
+ for i in range(0,max_depth_bucket+1):
+ try:
+ count = depth_count[i]
+ except:
+ count = 0
+
+ # use numbers for bars that are too long
+ if count<72:
+ bar = count*"*"
+ else:
+ bar = (72-8)*"*" + "(%d)*" % count
+ print "%3d: %s" % (i*10,bar)
+
+def cmp_depth(f1, f2):
+ return cmp(f1.depth, f2.depth)
+
+def main():
+ global debug
+
+ full_list = 0
+ show_histogram = 0
+ debug = 0
+ top_count = 10
+
+ if "-h" in sys.argv:
+ usage()
+
+ if "-f" in sys.argv:
+ full_list = 1
+ sys.argv.remove("-f")
+
+ if "-g" in sys.argv:
+ show_histogram = 1
+ sys.argv.remove("-g")
+
+ if "-t" in sys.argv:
+ top_count = sys.argv[sys.argv.index("-t")+1]
+ sys.argv.remove(top_count)
+ sys.argv.remove("-t")
+ top_count = int(top_count)
+
+ if "--debug" in sys.argv:
+ debug = 1
+ sys.argv.remove("--debug")
+
+ if "--version" in sys.argv or "-V" in sys.argv:
+ print "%s version %s" % (os.path.basename(sys.argv[0]),version)
+ sys.exit(0)
+
+ try:
+ filename = sys.argv[1]
+ except:
+ print "Error: missing filename to scan"
+ usage()
+
+ fd = open_assembly(filename)
+
+ functions = {}
+ func = None
+
+ max_cur_depth = 0
+ depth = 0
+ func_line_count = 0
+ PROGRAM_ENTRY_MAXLINES = 4
+
+ for line in fd.xreadlines():
+ # parse lines
+
+ # find function starts
+ try:
+ if line[8:10]==" <":
+ func_line = line
+ (func_addr_s,rest) = func_line.split(" ",1)
+ funcname = rest[1:-3]
+ #print line,
+ func_addr = int(func_addr_s, 16)
+ #print "func_addr=%x, func=%s" % (func_addr, func)
+ # record depth of last function
+ if func:
+ func.depth = max_cur_depth
+ dprint("stack depth: %d" % max_cur_depth)
+
+ # start new function
+ dprint("function: %s" % funcname)
+ func = function_class(funcname, func_addr)
+ functions[funcname] = func
+ depth = 0
+ max_cur_depth = 0
+ func_line_count = 0
+
+ except:
+ pass
+
+ func_line_count += 1
+
+ # calculate stack depth
+ # pattern is: initial register push (with "push {...}
+ # reservation of local stack space
+ if line.find("push\t") != -1 and \
+ func_line_count<PROGRAM_ENTRY_MAXLINES:
+ # parse push
+ (before, args) = line.split("push",1)
+ dprint("push args=%s" % args)
+ regs = line.split(",")
+ depth += 4 * len(regs)
+ if depth>max_cur_depth:
+ max_cur_depth = depth
+
+ dprint("depth=%d" % depth)
+
+ if line.find("sub\tsp, sp, #") != -1 and \
+ func_line_count<PROGRAM_ENTRY_MAXLINES:
+ # parse sub
+ (before, args) = line.split("sub",1)
+ if debug:
+ print "sub args=%s" % args
+ (sp1,sp2,imm) = line.split(",",2)
+ # next line splits: ' #84\t ; 0x54\n'
+ # into ['#84',';','0x54']
+ # take [0]th element, and strip leading '#'
+ #print "imm='%s'" % imm
+ depth += int(imm.split()[0][1:])
+ if depth>max_cur_depth:
+ max_cur_depth = depth
+
+ dprint("depth=%d" % depth)
+
+ # disable check for pops (used for debugging)
+ if None and line.find("pop\t") != -1:
+ # parse pop
+ (before, args) = line.split("pop",1)
+ dprint("pop args=%s" % args)
+ regs = line.split(",")
+ depth -= 4 * len(regs)
+ if depth<0:
+ print "Parser Error: function: %s, depth=%d" % \
+ (funcname, depth)
+ dprint("depth=%d" % depth)
+
+ # record depth of last function
+ if func:
+ func.depth = max_cur_depth
+ dprint("max stack depth: %d" % max_cur_depth)
+
+ fd.close()
+
+ if not functions:
+ print "No functions found. Done."
+ return
+
+ # calculate results
+ max_depth = 0
+ maxfunc = func
+ for func in functions.values():
+ if func.depth > max_depth:
+ max_depth = func.depth
+ maxfunc = func
+
+ print "============ RESULTS ==============="
+ print "number of functions = %d" % len(functions)
+ print "max function stack depth= %d" % maxfunc.depth
+ print "function with max depth = %s\n" % maxfunc.name
+
+ if full_list or top_count:
+ funclist = functions.values()
+ funclist.sort(cmp_depth)
+ print "%-32s %s" % ("Function Name ","Stack Depth")
+ print "%-32s %s" % ("=====================","===========")
+
+ if full_list:
+ top_count = len(funclist)
+
+ start = len(funclist)-top_count
+ for i in range(start, start+top_count):
+ func = funclist[i]
+ print "%-32s %4d" % (func.name, func.depth)
+
+ if show_histogram:
+ do_show_histogram(functions)
+
+if __name__=="__main__":
+ main()
--
1.6.6


\
 
 \ /
  Last update: 2011-10-19 01:35    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site