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| author |   Vineet Gupta <vgupta@synopsys.com> | 2013-05-27 18:51:27 +0530 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2013-06-22 19:23:25 +0530 |
| commit | ba3558c772ce1ac64d07f46b8c763349a0e51ba3 (patch) | |
| tree | e89141966f881bc363b5952b6f216ebbd69b4501 /arch/arc | |
| parent | ARC: Entry Handler tweaks: Simplify branch for in-kernel preemption (diff) | |
| download | linux-dev-ba3558c772ce1ac64d07f46b8c763349a0e51ba3.tar.xz linux-dev-ba3558c772ce1ac64d07f46b8c763349a0e51ba3.zip | |
ARC: K/U SP saved from one location in stack switching macro
This paves way for further simplifications.
There's an overhead of 1 insn for the non-common case of interrupt taken
from kernel mode.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc')
| -rw-r--r-- | arch/arc/include/asm/entry.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h index 5191945f3d39..2cf6aa08cfca 100644 --- a/arch/arc/include/asm/entry.h +++ b/arch/arc/include/asm/entry.h @@ -290,9 +290,8 @@ * safe-keeping not really needed, but it keeps the epilogue code * (SP restore) simpler/uniform. */ - b.d 77f - - st.a sp, [sp, -12] ; Make room for orig_r0 and orig_r8 + b.d 66f + mov r9, sp 88: /*------Intr/Ecxp happened in user mode, "switch" stack ------ */ @@ -311,6 +310,7 @@ /* With current tsk in r9, get it's kernel mode stack base */ GET_TSK_STACK_BASE r9, r9 +66: /* Save Pre Intr/Exception User SP on kernel stack */ st.a sp, [r9, -12] ; Make room for orig_r0 and orig_r8 @@ -323,7 +323,7 @@ /* set SP to point to kernel mode stack */ mov sp, r9 -77: /* ----- Stack Switched to kernel Mode, Now save REG FILE ----- */ + /* ----- Stack Switched to kernel Mode, Now save REG FILE ----- */ .endm |