summaryrefslogtreecommitdiff
path: root/arch/x86/entry
diff options
context:
space:
mode:
authorAndy Lutomirski <luto@kernel.org>2015-07-31 21:41:09 (GMT)
committerIngo Molnar <mingo@kernel.org>2015-08-05 08:54:35 (GMT)
commit5d73fc70996d9de0d1b2fc87e62dc51153204eba (patch)
treeffafd0c3dc587df0544c8165f6df4da4b1e37fb8 /arch/x86/entry
parentc5f69fde26d1581ee495f68bb9de4049c8168a04 (diff)
downloadlinux-5d73fc70996d9de0d1b2fc87e62dc51153204eba.tar.xz
x86/entry/32: Migrate to C exit path
This removes the hybrid asm-and-C implementation of exit work. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eric Paris <eparis@parisplace.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2baa438619ea6c027b40ec9fceacca52f09c74d09.1438378274.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/entry')
-rw-r--r--arch/x86/entry/entry_32.S62
1 files changed, 11 insertions, 51 deletions
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index a3c307a..b2909bf 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -256,14 +256,10 @@ ret_from_intr:
ENTRY(resume_userspace)
LOCKDEP_SYS_EXIT
- DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt
- # setting need_resched or sigpending
- # between sampling and the iret
+ DISABLE_INTERRUPTS(CLBR_ANY)
TRACE_IRQS_OFF
- movl TI_flags(%ebp), %ecx
- andl $_TIF_WORK_MASK, %ecx # is there any work to be done on
- # int/exception return?
- jne work_pending
+ movl %esp, %eax
+ call prepare_exit_to_usermode
jmp restore_all
END(ret_from_exception)
@@ -341,7 +337,7 @@ sysenter_after_call:
TRACE_IRQS_OFF
movl TI_flags(%ebp), %ecx
testl $_TIF_ALLWORK_MASK, %ecx
- jnz syscall_exit_work
+ jnz syscall_exit_work_irqs_off
sysenter_exit:
/* if something modifies registers it must also disable sysexit */
movl PT_EIP(%esp), %edx
@@ -377,13 +373,7 @@ syscall_after_call:
movl %eax, PT_EAX(%esp) # store the return value
syscall_exit:
LOCKDEP_SYS_EXIT
- DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt
- # setting need_resched or sigpending
- # between sampling and the iret
- TRACE_IRQS_OFF
- movl TI_flags(%ebp), %ecx
- testl $_TIF_ALLWORK_MASK, %ecx # current->work
- jnz syscall_exit_work
+ jmp syscall_exit_work
restore_all:
TRACE_IRQS_IRET
@@ -460,35 +450,6 @@ ldt_ss:
#endif
ENDPROC(entry_INT80_32)
- # perform work that needs to be done immediately before resumption
- ALIGN
-work_pending:
- testb $_TIF_NEED_RESCHED, %cl
- jz work_notifysig
-work_resched:
- call schedule
- LOCKDEP_SYS_EXIT
- DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt
- # setting need_resched or sigpending
- # between sampling and the iret
- TRACE_IRQS_OFF
- movl TI_flags(%ebp), %ecx
- andl $_TIF_WORK_MASK, %ecx # is there any work to be done other
- # than syscall tracing?
- jz restore_all
- testb $_TIF_NEED_RESCHED, %cl
- jnz work_resched
-
-work_notifysig: # deal with pending signals and
- # notify-resume requests
- TRACE_IRQS_ON
- ENABLE_INTERRUPTS(CLBR_NONE)
- movl %esp, %eax
- xorl %edx, %edx
- call do_notify_resume
- jmp resume_userspace
-END(work_pending)
-
# perform syscall exit tracing
ALIGN
syscall_trace_entry:
@@ -503,15 +464,14 @@ END(syscall_trace_entry)
# perform syscall exit tracing
ALIGN
-syscall_exit_work:
- testl $_TIF_WORK_SYSCALL_EXIT, %ecx
- jz work_pending
+syscall_exit_work_irqs_off:
TRACE_IRQS_ON
- ENABLE_INTERRUPTS(CLBR_ANY) # could let syscall_trace_leave() call
- # schedule() instead
+ ENABLE_INTERRUPTS(CLBR_ANY)
+
+syscall_exit_work:
movl %esp, %eax
- call syscall_trace_leave
- jmp resume_userspace
+ call syscall_return_slowpath
+ jmp restore_all
END(syscall_exit_work)
syscall_fault: