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| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2014-12-01 09:16:45 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2014-12-08 09:42:29 +0100 |
| commit | 832a771034bf62444796ab8868264c3ea9e50866 (patch) | |
| tree | 40f2a4daa8cb86927e77c07eaae2c06b8e885b73 /arch/s390 | |
| parent | ed7d56e174b11b76e2954f28605c5c16f8814fab (diff) | |
| download | linux-832a771034bf62444796ab8868264c3ea9e50866.tar.bz2 | |
s390/debug: avoid function call for debug_sprintf_*
debug_sprintf_event/exception are called even for debug events
with a disabling debug level. All other functions already do
the check in a wrapper function. Lets do the same here.
Due to the var_args the compiler rejects to make this function
inline. So let's wrap this via a macro.
This patch saves around 80 ns on my z196 for a KVM round trip (we
have two debug statements for entry and exit) when KVM is build as
a module.
The savings for built-in drivers is smaller as we then avoid the
PLT overhead for a function call.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/include/asm/debug.h | 29 | ||||
| -rw-r--r-- | arch/s390/kernel/debug.c | 12 |
2 files changed, 31 insertions, 10 deletions
diff --git a/arch/s390/include/asm/debug.h b/arch/s390/include/asm/debug.h index 530c15eb01e9..0206c8052328 100644 --- a/arch/s390/include/asm/debug.h +++ b/arch/s390/include/asm/debug.h @@ -151,9 +151,21 @@ debug_text_event(debug_info_t* id, int level, const char* txt) * stored in the s390dbf. See Documentation/s390/s390dbf.txt for more details! */ extern debug_entry_t * -debug_sprintf_event(debug_info_t* id,int level,char *string,...) +__debug_sprintf_event(debug_info_t *id, int level, char *string, ...) __attribute__ ((format(printf, 3, 4))); +#define debug_sprintf_event(_id, _level, _fmt, ...) \ +({ \ + debug_entry_t *__ret; \ + debug_info_t *__id = _id; \ + int __level = _level; \ + if ((!__id) || (__level > __id->level)) \ + __ret = NULL; \ + else \ + __ret = __debug_sprintf_event(__id, __level, \ + _fmt, ## __VA_ARGS__); \ + __ret; \ +}) static inline debug_entry_t* debug_exception(debug_info_t* id, int level, void* data, int length) @@ -194,9 +206,22 @@ debug_text_exception(debug_info_t* id, int level, const char* txt) * stored in the s390dbf. See Documentation/s390/s390dbf.txt for more details! */ extern debug_entry_t * -debug_sprintf_exception(debug_info_t* id,int level,char *string,...) +__debug_sprintf_exception(debug_info_t *id, int level, char *string, ...) __attribute__ ((format(printf, 3, 4))); +#define debug_sprintf_exception(_id, _level, _fmt, ...) \ +({ \ + debug_entry_t *__ret; \ + debug_info_t *__id = _id; \ + int __level = _level; \ + if ((!__id) || (__level > __id->level)) \ + __ret = NULL; \ + else \ + __ret = __debug_sprintf_exception(__id, __level, \ + _fmt, ## __VA_ARGS__);\ + __ret; \ +}) + int debug_register_view(debug_info_t* id, struct debug_view* view); int debug_unregister_view(debug_info_t* id, struct debug_view* view); diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c index ee8390da6ea7..c1f21aca76e7 100644 --- a/arch/s390/kernel/debug.c +++ b/arch/s390/kernel/debug.c @@ -1019,7 +1019,7 @@ debug_count_numargs(char *string) */ debug_entry_t* -debug_sprintf_event(debug_info_t* id, int level,char *string,...) +__debug_sprintf_event(debug_info_t *id, int level, char *string, ...) { va_list ap; int numargs,idx; @@ -1027,8 +1027,6 @@ debug_sprintf_event(debug_info_t* id, int level,char *string,...) debug_sprintf_entry_t *curr_event; debug_entry_t *active; - if((!id) || (level > id->level)) - return NULL; if (!debug_active || !id->areas) return NULL; numargs=debug_count_numargs(string); @@ -1050,14 +1048,14 @@ debug_sprintf_event(debug_info_t* id, int level,char *string,...) return active; } -EXPORT_SYMBOL(debug_sprintf_event); +EXPORT_SYMBOL(__debug_sprintf_event); /* * debug_sprintf_exception: */ debug_entry_t* -debug_sprintf_exception(debug_info_t* id, int level,char *string,...) +__debug_sprintf_exception(debug_info_t *id, int level, char *string, ...) { va_list ap; int numargs,idx; @@ -1065,8 +1063,6 @@ debug_sprintf_exception(debug_info_t* id, int level,char *string,...) debug_sprintf_entry_t *curr_event; debug_entry_t *active; - if((!id) || (level > id->level)) - return NULL; if (!debug_active || !id->areas) return NULL; @@ -1089,7 +1085,7 @@ debug_sprintf_exception(debug_info_t* id, int level,char *string,...) return active; } -EXPORT_SYMBOL(debug_sprintf_exception); +EXPORT_SYMBOL(__debug_sprintf_exception); /* * debug_register_view: |