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| author | Steven Rostedt <rostedt@goodmis.org> | 2008-08-14 15:45:09 -0400 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-10-14 10:34:47 +0200 |
| commit | 90d595fe5ca4b685465c068907e6e554760abea8 (patch) | |
| tree | 03f98454af8c6756177aa053ae7440373007f67d | |
| parent | 68bf21aa15c85d2e9b623dcda2b1ed8893275fa1 (diff) | |
| download | op-kernel-dev-90d595fe5ca4b685465c068907e6e554760abea8.zip op-kernel-dev-90d595fe5ca4b685465c068907e6e554760abea8.tar.gz | |
ftrace: enable mcount recording for modules
This patch enables the loading of the __mcount_section of modules and
changing all the callers of mcount into nops.
The modification is done before the init_module function is called, so
again, we do not need to use kstop_machine to make these changes.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | include/linux/ftrace.h | 3 | ||||
| -rw-r--r-- | kernel/module.c | 11 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 5 |
3 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index d4d6ab4..4936489 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -164,8 +164,11 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { } #ifdef CONFIG_FTRACE_MCOUNT_RECORD extern void ftrace_init(void); +extern void ftrace_init_module(unsigned long *start, unsigned long *end); #else static inline void ftrace_init(void) { } +static inline void +ftrace_init_module(unsigned long *start, unsigned long *end) { } #endif #endif /* _LINUX_FTRACE_H */ diff --git a/kernel/module.c b/kernel/module.c index 661d73d..d753fd9 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -47,6 +47,7 @@ #include <linux/license.h> #include <asm/sections.h> #include <linux/tracepoint.h> +#include <linux/ftrace.h> #if 0 #define DEBUGP printk @@ -1834,6 +1835,7 @@ static noinline struct module *load_module(void __user *umod, unsigned int markersstringsindex; unsigned int tracepointsindex; unsigned int tracepointsstringsindex; + unsigned int mcountindex; struct module *mod; long err = 0; void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ @@ -2124,6 +2126,9 @@ static noinline struct module *load_module(void __user *umod, tracepointsstringsindex = find_sec(hdr, sechdrs, secstrings, "__tracepoints_strings"); + mcountindex = find_sec(hdr, sechdrs, secstrings, + "__mcount_loc"); + /* Now do relocations. */ for (i = 1; i < hdr->e_shnum; i++) { const char *strtab = (char *)sechdrs[strindex].sh_addr; @@ -2184,6 +2189,12 @@ static noinline struct module *load_module(void __user *umod, mod->tracepoints + mod->num_tracepoints); #endif } + + if (mcountindex) { + void *mseg = (void *)sechdrs[mcountindex].sh_addr; + ftrace_init_module(mseg, mseg + sechdrs[mcountindex].sh_size); + } + err = module_finalize(hdr, sechdrs, mod); if (err < 0) goto cleanup; diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index df96d59..ea45bb1c 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1541,6 +1541,11 @@ static int ftrace_convert_nops(unsigned long *start, return 0; } +void ftrace_init_module(unsigned long *start, unsigned long *end) +{ + ftrace_convert_nops(start, end); +} + extern unsigned long __start_mcount_loc[]; extern unsigned long __stop_mcount_loc[]; |
