Commit-ID: 81683cc8277e79decff4d0cf82ae0e17d2fe465f
Gitweb: http://git.kernel.org/tip/81683cc8277e79decff4d0cf82ae0e17d2fe465f
Author: Ingo Molnar <mingo@xxxxxxxxxx>
AuthorDate: Wed, 22 Apr 2015 11:52:13 +0200
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 19 May 2015 15:47:17 +0200
x86/fpu: Factor out fpu__flush_thread() from flush_thread()
flush_thread() open codes a lot of FPU internals - create a separate
function for it in fpu/core.c.
Turns out that this does not hurt performance:
text data bss dec hex filename
11843039 1884440 1130496 14857975 e2b6f7 vmlinux.before
11843039 1884440 1130496 14857975 e2b6f7 vmlinux.after
and since this is a slowpath clarity comes first anyway.
We can reconsider inlining decisions after the FPU code has been cleaned up.
Reviewed-by: Borislav Petkov <bp@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/include/asm/i387.h | 1 +
arch/x86/kernel/fpu/core.c | 17 +++++++++++++++++
arch/x86/kernel/process.c | 14 +-------------
3 files changed, 19 insertions(+), 13 deletions(-)
diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index 6552a16..d6fc844 100644
--- a/arch/x86/include/asm/i387.h
+++ b/arch/x86/include/asm/i387.h
@@ -20,6 +20,7 @@ struct user_i387_struct;
extern int fpstate_alloc_init(struct task_struct *curr);
extern void fpstate_init(struct fpu *fpu);
+extern void fpu__flush_thread(struct task_struct *tsk);
extern int dump_fpu(struct pt_regs *, struct user_i387_struct *);
extern void math_state_restore(void);
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 9211582..787bf57 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -227,6 +227,23 @@ static int fpu__unlazy_stopped(struct task_struct *child)
return 0;
}
+void fpu__flush_thread(struct task_struct *tsk)
+{
+ if (!use_eager_fpu()) {
+ /* FPU state will be reallocated lazily at the first use. */
+ drop_fpu(tsk);
+ fpstate_free(&tsk->thread.fpu);
+ } else {
+ if (!tsk_used_math(tsk)) {
+ /* kthread execs. TODO: cleanup this horror. */
+ if (WARN_ON(fpstate_alloc_init(tsk)))
+ force_sig(SIGKILL, tsk);
+ user_fpu_begin();
+ }
+ restore_init_xstate();
+ }
+}
+
/*
* The xstateregs_active() routine is the same as the fpregs_active() routine,
* as the "regset->n" for the xstate regset will be updated based on the feature
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 6ab180f..52fd8f6 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -146,19 +146,7 @@ void flush_thread(void)
flush_ptrace_hw_breakpoint(tsk);
memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));
- if (!use_eager_fpu()) {
- /* FPU state will be reallocated lazily at the first use. */
- drop_fpu(tsk);
- fpstate_free(&tsk->thread.fpu);
- } else {
- if (!tsk_used_math(tsk)) {
- /* kthread execs. TODO: cleanup this horror. */
- if (WARN_ON(fpstate_alloc_init(tsk)))
- force_sig(SIGKILL, tsk);
- user_fpu_begin();
- }
- restore_init_xstate();
- }
+ fpu__flush_thread(tsk);
}
static void hard_disable_TSC(void)
--
To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
|