| Message ID | f7dcd4d1b5a9b77eaef50f22f4040a26c6b40487.1452884156.git.geoff@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Geoff, On 15/01/16 19:18, Geoff Levand wrote: Can I donate a commit message: Kexec and hibernate need to copy pages of memory, but may not have all of the kernel mapped, and are unable to call copy_page(). Convert copy_page() to a macro, so that it can be inlined in these situations. > Signed-off-by: Geoff Levand <geoff@infradead.org> > --- > arch/arm64/include/asm/assembler.h | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h > index 21979a4..c47a623 100644 > --- a/arch/arm64/include/asm/assembler.h > +++ b/arch/arm64/include/asm/assembler.h > @@ -24,6 +24,7 @@ > #define __ASM_ASSEMBLER_H > > #include <asm/asm-offsets.h> > +#include <asm/page.h> > #include <asm/pgtable-hwdef.h> > #include <asm/ptrace.h> > #include <asm/thread_info.h> > @@ -240,6 +241,24 @@ lr .req x30 // link register > .endm > > /* > + * copy_page - copy src to dest using temp registers t1-t8 > + */ > + .macro copy_page dest:req src:req t1:req t2:req t3:req t4:req t5:req t6:req t7:req t8:req > +1: ldp \t1, \t2, [\src] Using '1' as a label here means callers can't jump back over it using the same label. The convention with USER() and alternatives is to use unlikely values like '9999'. > + ldp \t3, \t4, [\src, #16] > + ldp \t5, \t6, [\src, #32] > + ldp \t7, \t8, [\src, #48] > + add \src, \src, #64 > + stnp \t1, \t2, [\dest] > + stnp \t3, \t4, [\dest, #16] > + stnp \t5, \t6, [\dest, #32] > + stnp \t7, \t8, [\dest, #48] > + add \dest, \dest, #64 > + tst \src, #(PAGE_SIZE - 1) > + b.ne 1b > + .endm It may be worth updating lib/copy_page.S to use this macro. I will fix the code in hibernate to use this! Thanks, James
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 21979a4..c47a623 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -24,6 +24,7 @@ #define __ASM_ASSEMBLER_H #include <asm/asm-offsets.h> +#include <asm/page.h> #include <asm/pgtable-hwdef.h> #include <asm/ptrace.h> #include <asm/thread_info.h> @@ -240,6 +241,24 @@ lr .req x30 // link register .endm /* + * copy_page - copy src to dest using temp registers t1-t8 + */ + .macro copy_page dest:req src:req t1:req t2:req t3:req t4:req t5:req t6:req t7:req t8:req +1: ldp \t1, \t2, [\src] + ldp \t3, \t4, [\src, #16] + ldp \t5, \t6, [\src, #32] + ldp \t7, \t8, [\src, #48] + add \src, \src, #64 + stnp \t1, \t2, [\dest] + stnp \t3, \t4, [\dest, #16] + stnp \t5, \t6, [\dest, #32] + stnp \t7, \t8, [\dest, #48] + add \dest, \dest, #64 + tst \src, #(PAGE_SIZE - 1) + b.ne 1b + .endm + +/* * Annotate a function as position independent, i.e., safe to be called before * the kernel virtual mapping is activated. */
Signed-off-by: Geoff Levand <geoff@infradead.org> --- arch/arm64/include/asm/assembler.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)