| Message ID | 1502130965-18710-11-git-send-email-mark.rutland@arm.com |
|---|---|
| State | New |
| Headers | show |
| Series | arm64: VMAP_STACK support | expand |
On Mon, Aug 07, 2017 at 07:36:01PM +0100, Mark Rutland wrote: > From: Ard Biesheuvel <ard.biesheuvel@linaro.org> > > Given that adr_this_cpu already requires a temp register in addition > to the destination register, tweak the instruction sequence so that sp > may be used as well. > > This will simplify switching to per-cpu stacks in subsequent patches. While > this limits the range of adr_this_cpu, to +/-4GiB, we don't currently use > adr_this_cpu in modules, and this is not problematic for the main kernel image. > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> > [Mark: add more commit text] > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: James Morse <james.morse@arm.com> > Cc: Laura Abbott <labbott@redhat.com> > Cc: Will Deacon <will.deacon@arm.com> > --- > arch/arm64/include/asm/assembler.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h > index 610a420..4775af5 100644 > --- a/arch/arm64/include/asm/assembler.h > +++ b/arch/arm64/include/asm/assembler.h > @@ -235,7 +235,8 @@ > * @tmp: scratch register > */ > .macro adr_this_cpu, dst, sym, tmp > - adr_l \dst, \sym > + adrp \tmp, \sym > + add \dst, \tmp, #:lo12:\sym > mrs \tmp, tpidr_el1 > add \dst, \dst, \tmp > .endm Nitpick: it may be worth adding an #ifndef MODULE around these macros, together with a comment, just in case. There are other macros in this file like adr_l which are used in modules (crypto). -- Catalin
On Mon, Aug 14, 2017 at 06:13:39PM +0100, Catalin Marinas wrote: > On Mon, Aug 07, 2017 at 07:36:01PM +0100, Mark Rutland wrote: > > .macro adr_this_cpu, dst, sym, tmp > > - adr_l \dst, \sym > > + adrp \tmp, \sym > > + add \dst, \tmp, #:lo12:\sym > > mrs \tmp, tpidr_el1 > > add \dst, \dst, \tmp > > .endm > > Nitpick: it may be worth adding an #ifndef MODULE around these macros, > together with a comment, just in case. There are other macros in this > file like adr_l which are used in modules (crypto). I've folded in the below, in keeping with the other MODULE fallbacks. Thanks, Mark. ---->8----diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 4775af5..50c5592 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -230,13 +230,18 @@ .endm /* - * @dst: Result of per_cpu(sym, smp_processor_id()) + * @dst: Result of per_cpu(sym, smp_processor_id()), can be SP for + * non-module code * @sym: The name of the per-cpu variable * @tmp: scratch register */ .macro adr_this_cpu, dst, sym, tmp +#ifndef MODULE adrp \tmp, \sym add \dst, \tmp, #:lo12:\sym +#else + adr_l \tmp, \sym +#endif mrs \tmp, tpidr_el1 add \dst, \dst, \tmp .endm
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 610a420..4775af5 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -235,7 +235,8 @@ * @tmp: scratch register */ .macro adr_this_cpu, dst, sym, tmp - adr_l \dst, \sym + adrp \tmp, \sym + add \dst, \tmp, #:lo12:\sym mrs \tmp, tpidr_el1 add \dst, \dst, \tmp .endm