diff options
| author | Brian Gerst <brgerst@gmail.com> | 2016-08-13 12:38:19 -0400 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-08-24 12:31:41 +0200 |
| commit | 0100301bfdf56a2a370c7157b5ab0fbf9313e1cd (patch) | |
| tree | f8a339f20fb486a1ebe029d1c409e94c9bf8d67a /arch/x86/kernel/smpboot.c | |
| parent | 7b32aeadbc95d4a41402c1c0da6aa3ab51af4c10 (diff) | |
sched/x86: Rewrite the switch_to() code
Move the low-level context switch code to an out-of-line asm stub instead of
using complex inline asm. This allows constructing a new stack frame for the
child process to make it seamlessly flow to ret_from_fork without an extra
test and branch in __switch_to(). It also improves code generation for
__schedule() by using the C calling convention instead of clobbering all
registers.
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1471106302-10159-5-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/smpboot.c')
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index c85d2c636092..7e52f83d3a4b 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -942,7 +942,6 @@ void common_cpu_up(unsigned int cpu, struct task_struct *idle) per_cpu(cpu_current_top_of_stack, cpu) = (unsigned long)task_stack_page(idle) + THREAD_SIZE; #else - clear_tsk_thread_flag(idle, TIF_FORK); initial_gs = per_cpu_offset(cpu); #endif } |