Commit-ID: 5d73fc70996d9de0d1b2fc87e62dc51153204eba Gitweb: http://git.kernel.org/tip/5d73fc70996d9de0d1b2fc87e62dc51153204eba Author: Andy Lutomirski <[email protected]> AuthorDate: Fri, 31 Jul 2015 14:41:09 -0700 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 5 Aug 2015 10:54:35 +0200
x86/entry/32: Migrate to C exit path This removes the hybrid asm-and-C implementation of exit work. Signed-off-by: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Eric Paris <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/2baa438619ea6c027b40ec9fceacca52f09c74d09.1438378274.git.l...@kernel.org Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/entry/entry_32.S | 62 +++++++++-------------------------------------- 1 file 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: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
