[tip:x86/pti] x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function
From: tip-bot for Dominik Brodowski
Date: Wed Feb 21 2018 - 11:59:36 EST
Commit-ID: 0e34d226342c27c4f96138b211547d423e4be8a1
Gitweb: https://git.kernel.org/tip/0e34d226342c27c4f96138b211547d423e4be8a1
Author: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
AuthorDate: Tue, 20 Feb 2018 22:01:08 +0100
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 21 Feb 2018 16:54:03 +0100
x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function
The PUSH_AND_CLEAR_REGS macro is able to insert the GP registers
"above" the original return address. This allows us to move a sizeable
part of the interrupt entry macro to an interrupt entry helper function:
text data bss dec hex filename
21088 0 0 21088 5260 entry_64.o-orig
18006 0 0 18006 4656 entry_64.o
Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Brian Gerst <brgerst@xxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: dan.j.williams@xxxxxxxxx
Link: http://lkml.kernel.org/r/20180220210113.6725-2-linux@xxxxxxxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/entry/entry_64.S | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 7a53879..b0ae0c3 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -525,6 +525,14 @@ END(irq_entries_start)
*
* Entry runs with interrupts off.
*/
+ENTRY(interrupt_entry)
+ UNWIND_HINT_FUNC
+
+ PUSH_AND_CLEAR_REGS save_ret=1
+ ENCODE_FRAME_POINTER 8
+
+ ret
+END(interrupt_entry)
/* 0(%rsp): ~(interrupt number) */
.macro interrupt func
@@ -536,8 +544,7 @@ END(irq_entries_start)
call switch_to_thread_stack
1:
- PUSH_AND_CLEAR_REGS
- ENCODE_FRAME_POINTER
+ call interrupt_entry
testb $3, CS(%rsp)
jz 1f