On Fri, 24 Aug 2018 14:38:33 PDT (-0700), Jason@xxxxxxxxx wrote:
Sometimes it's useful to amortize calls to XSAVE/XRSTOR and the related
FPU/SIMD functions over a number of calls, because FPU restoration is
quite expensive. This adds a simple header for carrying out this pattern:
simd_context_t simd_context = simd_get();
while ((item = get_item_from_queue()) != NULL) {
encrypt_item(item, simd_context);
simd_context = simd_relax(simd_context);
}
simd_put(simd_context);
The relaxation step ensures that we don't trample over preemption, and
the get/put API should be a familiar paradigm in the kernel.
Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Samuel Neves <sneves@xxxxxxxxx>
Cc: linux-arch@xxxxxxxxxxxxxxx
---
arch/alpha/include/asm/Kbuild | 5 ++--
arch/arc/include/asm/Kbuild | 1 +
arch/arm/include/asm/simd.h | 42 ++++++++++++++++++++++++++++++
arch/arm64/include/asm/simd.h | 37 +++++++++++++++++++++-----
arch/c6x/include/asm/Kbuild | 3 ++-
arch/h8300/include/asm/Kbuild | 3 ++-
arch/hexagon/include/asm/Kbuild | 1 +
arch/ia64/include/asm/Kbuild | 1 +
arch/m68k/include/asm/Kbuild | 1 +
arch/microblaze/include/asm/Kbuild | 1 +
arch/mips/include/asm/Kbuild | 1 +
arch/nds32/include/asm/Kbuild | 7 ++---
arch/nios2/include/asm/Kbuild | 1 +
arch/openrisc/include/asm/Kbuild | 7 ++---
arch/parisc/include/asm/Kbuild | 1 +
arch/powerpc/include/asm/Kbuild | 3 ++-
arch/riscv/include/asm/Kbuild | 3 ++-
arch/s390/include/asm/Kbuild | 3 ++-
arch/sh/include/asm/Kbuild | 1 +
arch/sparc/include/asm/Kbuild | 1 +
arch/um/include/asm/Kbuild | 3 ++-
arch/unicore32/include/asm/Kbuild | 1 +
arch/x86/include/asm/simd.h | 30 ++++++++++++++++++++-
arch/xtensa/include/asm/Kbuild | 1 +
include/asm-generic/simd.h | 15 +++++++++++
include/linux/simd.h | 28 ++++++++++++++++++++
26 files changed, 180 insertions(+), 21 deletions(-)
create mode 100644 arch/arm/include/asm/simd.h
create mode 100644 include/linux/simd.h
...
diff --git a/arch/riscv/include/asm/Kbuild b/arch/riscv/include/asm/Kbuild
index 576ffdca06ba..8d3e7aef3234 100644
--- a/arch/riscv/include/asm/Kbuild
+++ b/arch/riscv/include/asm/Kbuild
@@ -4,9 +4,9 @@ generic-y += checksum.h
generic-y += cputime.h
generic-y += device.h
generic-y += div64.h
-generic-y += dma.h
generic-y += dma-contiguous.h
generic-y += dma-mapping.h
+generic-y += dma.h
generic-y += emergency-restart.h
generic-y += errno.h
generic-y += exec.h
If this is the canonical ordering and doing so makes your life easier then I'm
OK taking this as a separate patch into the RISC-V tree, but if not then feel
free to roll something like this up into your next patch set.
@@ -45,6 +45,7 @@ generic-y += setup.h
generic-y += shmbuf.h
generic-y += shmparam.h
generic-y += signal.h
+generic-y += simd.h
generic-y += socket.h
generic-y += sockios.h
generic-y += stat.h
Either way, this looks fine for as far as the RISC-V stuff goes as it's pretty
much a NOP. As long as it stays a NOP then feel free to add a
Reviewed-by: Palmer Dabbelt <palmer@xxxxxxxxxx>
as far as the RISC-V parts are conceded. It looks like there's a lot of other
issues, though, so it's not much of a review :)
