Messages in this thread Patch in this message | | | Date | Tue, 2 Jun 2015 01:24:57 -0700 | From | tip-bot for Jan Beulich <> | Subject | [tip:x86/asm] x86/asm/entry/64: Use negative immediates for stack adjustments |
| |
Commit-ID: 2bf557ea3f49576fabe24cd5daf1a34e9ee22c3c Gitweb: http://git.kernel.org/tip/2bf557ea3f49576fabe24cd5daf1a34e9ee22c3c Author: Jan Beulich <JBeulich@suse.com> AuthorDate: Mon, 1 Jun 2015 13:02:55 +0100 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Tue, 2 Jun 2015 10:10:09 +0200
x86/asm/entry/64: Use negative immediates for stack adjustments
Doing so allows adjustments by 128 bytes (occurring for REMOVE_PT_GPREGS_FROM_STACK 8 uses) to be expressed with a single byte immediate.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Andy Lutomirski <luto@amacapital.net> 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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/556C660F020000780007FB60@mail.emea.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- arch/x86/include/asm/calling.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/calling.h b/arch/x86/include/asm/calling.h index 0d76acc..f4e6308 100644 --- a/arch/x86/include/asm/calling.h +++ b/arch/x86/include/asm/calling.h @@ -89,7 +89,7 @@ For 32-bit we have the following conventions - kernel is built with #define SIZEOF_PTREGS 21*8 .macro ALLOC_PT_GPREGS_ON_STACK addskip=0 - subq $15*8+\addskip, %rsp + addq $-(15*8+\addskip), %rsp .endm .macro SAVE_C_REGS_HELPER offset=0 rax=1 rcx=1 r8910=1 r11=1 @@ -201,7 +201,7 @@ For 32-bit we have the following conventions - kernel is built with .endm .macro REMOVE_PT_GPREGS_FROM_STACK addskip=0 - addq $15*8+\addskip, %rsp + subq $-(15*8+\addskip), %rsp .endm .macro icebp
| |