path: root/arch/s390/include/asm/syscall.h
diff options
authorMartin Schwidefsky <>2013-04-24 12:58:39 +0200
committerMartin Schwidefsky <>2013-04-26 09:07:05 +0200
commit616498813b11ffefe1ed36b9f2e4fd2cdbd22f15 (patch)
tree1748b3171ab5cf1ada0c0bbeef285352c37edfcd /arch/s390/include/asm/syscall.h
parentdc7ee00d4771b3218b10e09e1071ee6eb176d381 (diff)
s390: system call path micro optimization
Add a pointer to the system call table to the thread_info structure. The TIF_31BIT bit is set or cleared by SET_PERSONALITY exactly once for the lifetime of a process. With the pointer to the correct system call table in thread_info the system call code in entry64.S path can drop the check for TIF_31BIT which saves a couple of instructions. Signed-off-by: Martin Schwidefsky <>
Diffstat (limited to 'arch/s390/include/asm/syscall.h')
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
index fe7b99759e12..cd29d2f4e4f3 100644
--- a/arch/s390/include/asm/syscall.h
+++ b/arch/s390/include/asm/syscall.h
@@ -23,6 +23,7 @@
* type here is what we want [need] for both 32 bit and 64 bit systems.
extern const unsigned int sys_call_table[];
+extern const unsigned int sys_call_table_emu[];
static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)