x86/entry/64: Introduce the PUSH_AND_CLEAN_REGS macro
authorDominik Brodowski <linux@dominikbrodowski.net>
Sun, 11 Feb 2018 10:49:45 +0000 (11:49 +0100)
committerIngo Molnar <mingo@kernel.org>
Tue, 13 Feb 2018 08:04:53 +0000 (09:04 +0100)
commit3f01daecd545e818098d84fd1ad43e19a508d705
treed70e4a362d5c8c41ef771107726a8e0ff4972d69
parentf7bafa2b05ef25eda1d9179fd930b0330cf2b7d1
x86/entry/64: Introduce the PUSH_AND_CLEAN_REGS macro

Those instances where ALLOC_PT_GPREGS_ON_STACK is called just before
SAVE_AND_CLEAR_REGS can trivially be replaced by PUSH_AND_CLEAN_REGS.
This macro uses PUSH instead of MOV and should therefore be faster, at
least on newer CPUs.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Link: http://lkml.kernel.org/r/20180211104949.12992-5-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/entry/calling.h
arch/x86/entry/entry_64.S