xref: /linux/scripts/mksysmap (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1*1da177e4SLinus Torvalds#!/bin/sh -x
2*1da177e4SLinus Torvalds# Based on the vmlinux file create the System.map file
3*1da177e4SLinus Torvalds# System.map is used by module-init tools and some debugging
4*1da177e4SLinus Torvalds# tools to retreive the actual addresses of symbols in the kernel.
5*1da177e4SLinus Torvalds#
6*1da177e4SLinus Torvalds# Usage
7*1da177e4SLinus Torvalds# mksysmap vmlinux System.map
8*1da177e4SLinus Torvalds
9*1da177e4SLinus Torvalds
10*1da177e4SLinus Torvalds#####
11*1da177e4SLinus Torvalds# Generate System.map (actual filename passed as second argument)
12*1da177e4SLinus Torvalds
13*1da177e4SLinus Torvalds# $NM produces the following output:
14*1da177e4SLinus Torvalds# f0081e80 T alloc_vfsmnt
15*1da177e4SLinus Torvalds
16*1da177e4SLinus Torvalds#   The second row specify the type of the symbol:
17*1da177e4SLinus Torvalds#   A = Absolute
18*1da177e4SLinus Torvalds#   B = Uninitialised data (.bss)
19*1da177e4SLinus Torvalds#   C = Comon symbol
20*1da177e4SLinus Torvalds#   D = Initialised data
21*1da177e4SLinus Torvalds#   G = Initialised data for small objects
22*1da177e4SLinus Torvalds#   I = Indirect reference to another symbol
23*1da177e4SLinus Torvalds#   N = Debugging symbol
24*1da177e4SLinus Torvalds#   R = Read only
25*1da177e4SLinus Torvalds#   S = Uninitialised data for small objects
26*1da177e4SLinus Torvalds#   T = Text code symbol
27*1da177e4SLinus Torvalds#   U = Undefined symbol
28*1da177e4SLinus Torvalds#   V = Weak symbol
29*1da177e4SLinus Torvalds#   W = Weak symbol
30*1da177e4SLinus Torvalds#   Corresponding small letters are local symbols
31*1da177e4SLinus Torvalds
32*1da177e4SLinus Torvalds# For System.map filter away:
33*1da177e4SLinus Torvalds#   a - local absolute symbols
34*1da177e4SLinus Torvalds#   U - undefined global symbols
35*1da177e4SLinus Torvalds#   w - local weak symbols
36*1da177e4SLinus Torvalds
37*1da177e4SLinus Torvalds# readprofile starts reading symbols when _stext is found, and
38*1da177e4SLinus Torvalds# continue until it finds a symbol which is not either of 'T', 't',
39*1da177e4SLinus Torvalds# 'W' or 'w'. __crc_ are 'A' and placed in the middle
40*1da177e4SLinus Torvalds# so we just ignore them to let readprofile continue to work.
41*1da177e4SLinus Torvalds# (At least sparc64 has __crc_ in the middle).
42*1da177e4SLinus Torvalds
43*1da177e4SLinus Torvalds$NM -n $1 | grep -v '\( [aUw] \)\|\(__crc_\)\|\( \$[adt]\)' > $2
44*1da177e4SLinus Torvalds
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