@@ -157,13 +157,6 @@ static inline void arch_unmask_irq(unsigned int irq)
flag \scratch
.endm
-.macro IRQ_DISABLE_SAVE scratch, save
- lr \scratch, [status32]
- mov \save, \scratch /* Make a copy */
- bic \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
- flag \scratch
-.endm
-
.macro IRQ_ENABLE scratch
lr \scratch, [status32]
or \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
@@ -642,6 +642,9 @@ resume_kernel_mode:
#ifdef CONFIG_PREEMPT
+ ; This is a must for preempt_schedule_irq()
+ IRQ_DISABLE r9
+
; Can't preempt if preemption disabled
GET_CURR_THR_INFO_FROM_SP r10
ld r8, [r10, THREAD_INFO_PREEMPT_COUNT]
@@ -651,8 +654,6 @@ resume_kernel_mode:
ld r9, [r10, THREAD_INFO_FLAGS]
bbit0 r9, TIF_NEED_RESCHED, restore_regs
- IRQ_DISABLE r9
-
; Invoke PREEMPTION
bl preempt_schedule_irq
@@ -665,12 +666,11 @@ resume_kernel_mode:
;
; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap)
; IRQ shd definitely not happen between now and rtie
+; All 2 entry points to here already disable interrupts
restore_regs :
- ; Disable Interrupts while restoring reg-file back
- ; XXX can this be optimised out
- IRQ_DISABLE_SAVE r9, r10 ;@r10 has prisitine (pre-disable) copy
+ lr r10, [status32]
; Restore REG File. In case multiple Events outstanding,
; use the same priorty as rtie: EXCPN, L2 IRQ, L1 IRQ, None
This is a note to let you know that I have just added a patch titled ARC: Entry Handler tweaks: Optimize away redundant IRQ_DISABLE_SAVE to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.11.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From de419468ed4519f57ca700006e3d1bcf270a4cc9 Mon Sep 17 00:00:00 2001 From: Vineet Gupta <vgupta@synopsys.com> Date: Tue, 9 Jul 2013 17:06:40 +0530 Subject: ARC: Entry Handler tweaks: Optimize away redundant IRQ_DISABLE_SAVE commit fce16bc35ae4a45634f3dc348d8d297a25c277cf upstream. In the exception return path, for both U/K cases, intr are already disabled (for various existing reasons). So when we drop down to @restore_regs, we need not redo that. There was subtle issue - when intr were NOT being disabled for ret-to-kernel-but-no-preemption case - now fixed by moving the IRQ_DISABLE further up in @resume_kernel_mode. So what do we gain: * Shaves off a few insn in return path. * Eliminates the need for IRQ_DISABLE_SAVE assembler macro for ARCv2 hence allows for entry code sharing. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/arc/include/asm/irqflags.h | 7 ------- arch/arc/kernel/entry.S | 10 +++++----- 2 files changed, 5 insertions(+), 12 deletions(-) -- 1.9.1