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Subject[PATCH v2 28/36] x86/asm: Remove thread_info.sysenter_return
Date
It's no longer needed.

We could reinstate something like it as an optimization, which would
remove two cachelines from the fast syscall entry working set. I
benchmarked it, and it makes no difference whatsoever to the
performance of cache-hot compat syscalls on Sandy Bridge.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
arch/x86/include/asm/thread_info.h | 1 -
arch/x86/kernel/asm-offsets.c | 3 ---
2 files changed, 4 deletions(-)

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 8afdc3e44247..a1ecd214d227 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -59,7 +59,6 @@ struct thread_info {
__u32 cpu; /* current CPU */
int saved_preempt_count;
mm_segment_t addr_limit;
- void __user *sysenter_return;
unsigned int sig_on_uaccess_error:1;
unsigned int uaccess_err:1; /* uaccess failed */
};
diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
index 8e3d22a1af94..95a18e25d5bf 100644
--- a/arch/x86/kernel/asm-offsets.c
+++ b/arch/x86/kernel/asm-offsets.c
@@ -54,9 +54,6 @@ void common(void) {
OFFSET(IA32_SIGCONTEXT_ip, sigcontext_ia32, ip);

BLANK();
- OFFSET(TI_sysenter_return, thread_info, sysenter_return);
-
- BLANK();
OFFSET(IA32_RT_SIGFRAME_sigcontext, rt_sigframe_ia32, uc.uc_mcontext);
#endif

--
2.4.3


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