(Add John F. Reiser in this loop)
On 10/23/10, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> On Fri, 2010-10-22 at 14:10 -0700, David Daney wrote:
>> On 10/22/2010 01:58 PM, Wu Zhangjin wrote:
>> > From: Wu Zhangjin<wuzhangjin@xxxxxxxxx>
>> >
>> > In some situations(with related kernel config and gcc options), the
>> > modules may have the same address space as the core kernel space, so
>> > mcount_regex for modules should also match R_MIPS_26.
>> >
>>
>> I think Steve is rewriting this bit to be a pure C program. Is this
>> file even used anymore? If so for how long?
>
> It's already in mainline, but is only supported for x86 for now. Until
> we verify that it works for other archs (which is up to you guys to
> verify) the script will still be used.
>
> Also, I did not write it, John Reiser did. I just cleaned it up a bit
> and got it working with the build system.
Just applied this tmp patch to try the basic function.
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index ce8af84..3bf1c0c 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -9,6 +9,7 @@ config MIPS
select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_DYNAMIC_FTRACE
select HAVE_FTRACE_MCOUNT_RECORD
+ select HAVE_C_RECORDMCOUNT
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_KPROBES
select HAVE_KRETPROBES
diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c
index 26e1271..0fb200f 100644
--- a/scripts/recordmcount.c
+++ b/scripts/recordmcount.c
@@ -270,6 +270,7 @@ do_file(char const *const fname)
case EM_IA_64: reltype = R_IA64_IMM64; gpfx = '_'; break;
case EM_PPC: reltype = R_PPC_ADDR32; gpfx = '_'; break;
case EM_PPC64: reltype = R_PPC64_ADDR64; gpfx = '_'; break;
+ case EM_MIPS: reltype = R_MIPS_26; gpfx = '_'; break;
case EM_S390: /* reltype: e_class */ gpfx = '_'; break;
case EM_SH: reltype = R_SH_DIR32; break;
case EM_SPARCV9: reltype = R_SPARC_64; gpfx = '_'; break;
(Note: The above patch is not enough, for the modules with
-mlong-calls, the reltype should be R_MIPS_HI16, and we may also need
to add our specific code for sift_rel_mcount() to get the right
location of the _mcount calling site)
but failed with the following error:
$ make ARCH=mips CROSS_COMPILE=mips64el-unknown-linux-gnu-
CHK include/linux/version.h
CHK include/generated/utsrelease.h
HOSTCC scripts/basic/fixdep
HOSTCC scripts/basic/docproc
scripts/basic/docproc.c: In function ‘docsect’:
scripts/basic/docproc.c:336: warning: ignoring return value of
‘asprintf’, declared with attribute warn_unused_result
Checking missing-syscalls for N32
CALL scripts/checksyscalls.sh
Checking missing-syscalls for O32
CALL scripts/checksyscalls.sh
CC kernel/bounds.s
GEN include/generated/bounds.h
CC arch/mips/kernel/asm-offsets.s
GEN include/generated/asm-offsets.h
CALL scripts/checksyscalls.sh
CC scripts/mod/empty.o
HOSTCC scripts/mod/mk_elfconfig
MKELF scripts/mod/elfconfig.h
HOSTCC scripts/mod/file2alias.o
HOSTCC scripts/mod/modpost.o
HOSTCC scripts/mod/sumversion.o
HOSTLD scripts/mod/modpost
HOSTCC scripts/kallsyms
HOSTCC scripts/conmakehash
HOSTCC scripts/bin2c
HOSTCC scripts/recordmcount
CC init/main.o
/bin/sh: line 1: 21835 Segmentation fault scripts/recordmcount "init/main.o"
make[1]: *** [init/main.o] Error 139
make: *** [init] Error 2
I traced the problem and found it was triggered by the 201 line of
scripts/recordmcount.h:
198 if (!mcountsym) {
199 Elf_Sym const *const symp =
200 &sym0[ELF_R_SYM(_w(relp->r_info))];
*201 char const *symname = &str0[w(symp->st_name)];*
202
203 if ('.' == symname[0])
204 ++symname; /* ppc64 hack */
Exactly, it was triggered by: symp->st_name, symp is normal address,
i.e. 0xa01831f0, but perhaps the content pointed by this address may
not exist or is not allocated before?
Did I miss something for MIPS specific support?
By the way, because MIPS need to cope with its modules
particularly(differ from the module):
for kernel:
# 10: 03e0082d move at,ra
# 14: 0c000000 jal 0
# 14: R_MIPS_26 _mcount --> we
record this for MIPS kernel
# 14: R_MIPS_NONE *ABS*
# 14: R_MIPS_NONE *ABS*
# 18: 00020021 nop
for module:
# c: 3c030000 lui v1,0x0
# c: R_MIPS_HI16 _mcount --> we record
this for MIPS module
# c: R_MIPS_NONE *ABS*
# c: R_MIPS_NONE *ABS*
# 10: 64630000 daddiu v1,v1,0
# 10: R_MIPS_LO16 _mcount
# 10: R_MIPS_NONE *ABS*
# 10: R_MIPS_NONE *ABS*
# 14: 03e0082d move at,ra
# 18: 0060f809 jalr v1
# label:
But I found there was only one argument: /path/to/file.o passed to
scripts/recordmount:
scripts/Makefile.build
217 cmd_record_mcount = if [ $(@) != "scripts/mod/empty.o" ]; then
\
218 $(objtree)/scripts/recordmcount "$(@)";
\
219 fi;
220 else
So, should we pass "$(if $(part-of-module),1,0)" to the C version of
recordmcount?
Regards,
Wu Zhangjin
