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| author |   Denys Vlasenko <dvlasenk@redhat.com> | 2015-03-30 20:09:31 +0200 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2015-03-31 09:31:11 +0200 |
| commit | 627276cb55f33e2dc56eab5b973937c128b7704c (patch) | |
| tree | f1e0a343d2a64d19841bdd83c30831db3bbbd863 /arch/x86/kernel/entry_64.S | |
| parent | x86/asm/entry/32: Make register zero-extension more prominent (diff) | |
| download | linux-dev-627276cb55f33e2dc56eab5b973937c128b7704c.tar.xz linux-dev-627276cb55f33e2dc56eab5b973937c128b7704c.zip | |
x86/asm/entry/64: Move retint_kernel code block closer to its user
The "retint_kernel" code block is misplaced. Since its logical
continuation is "retint_restore_args", it is more natural to
place it above that label. This also makes two jumps "short".
This change only moves code block around, without changing
logic.
This enables the next simplification: making
"retint_restore_args" label a local numeric one.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1427738975-7391-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/entry_64.S')
| -rw-r--r-- | arch/x86/kernel/entry_64.S | 25 |
1 files changed, 13 insertions, 12 deletions
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index dbfc8875d735..34d60c34fca8 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -740,7 +740,19 @@ opportunistic_sysret_failed: SWAPGS jmp restore_args -retint_restore_args: /* return to kernel space */ +/* Returning to kernel space */ +#ifdef CONFIG_PREEMPT + /* Interrupts are off */ + /* Check if we need preemption */ +ENTRY(retint_kernel) + cmpl $0,PER_CPU_VAR(__preempt_count) + jnz retint_restore_args + bt $9,EFLAGS(%rsp) /* interrupts were off? */ + jnc retint_restore_args + call preempt_schedule_irq + jmp exit_intr +#endif +retint_restore_args: DISABLE_INTERRUPTS(CLBR_ANY) /* * The iretq could re-enable interrupts: @@ -830,17 +842,6 @@ retint_signal: GET_THREAD_INFO(%rcx) jmp retint_with_reschedule -#ifdef CONFIG_PREEMPT - /* Returning to kernel space. Check if we need preemption */ - /* rcx: threadinfo. interrupts off. */ -ENTRY(retint_kernel) - cmpl $0,PER_CPU_VAR(__preempt_count) - jnz retint_restore_args - bt $9,EFLAGS(%rsp) /* interrupts off? */ - jnc retint_restore_args - call preempt_schedule_irq - jmp exit_intr -#endif CFI_ENDPROC END(common_interrupt) |