linux/arch
Dave Martin 159fd7b8d3 arm64/sve: Write ZCR_EL1 on context switch only if changed
Writes to ZCR_EL1 are self-synchronising, and so may be expensive
in typical implementations.

This patch adopts the approach used for costly system register
writes elsewhere in the kernel: the system register write is
suppressed if it would not change the stored value.

Since the common case will be that of switching between tasks that
use the same vector length as one another, prediction hit rates on
the conditional branch should be reasonably good, with lower
expected amortised cost than the unconditional execution of a
heavyweight self-synchronising instruction.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-17 18:19:53 +01:00
..
alpha mm: introduce MAP_FIXED_NOREPLACE 2018-04-11 10:28:38 -07:00
arc kbuild: mark $(targets) as .SECONDARY and remove .PRECIOUS markers 2018-04-07 19:04:02 +09:00
arm KVM fixes for v4.17-rc3 2018-04-27 16:13:31 -07:00
arm64 arm64/sve: Write ZCR_EL1 on context switch only if changed 2018-05-17 18:19:53 +01:00
c6x c6x: pass endianness info to sparse 2018-04-10 09:58:58 -04:00
h8300 h8300: remove extraneous __BIG_ENDIAN definition 2018-03-22 17:07:01 -07:00
hexagon hexagon: export csum_partial_copy_nocheck 2018-05-01 15:49:50 -05:00
ia64 pci-v4.17-changes 2018-04-06 18:31:06 -07:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2018-04-09 09:15:46 -07:00
microblaze Microblaze patches for 4.17-rc1 2018-04-12 10:18:02 -07:00
mips MIPS fixes for 4.17-rc2 2018-04-20 08:25:31 -07:00
nds32 page cache: use xa_lock 2018-04-11 10:28:39 -07:00
nios2 nios2 update for v4.17-rc1 2018-04-11 16:02:18 -07:00
openrisc OpenRISC updates for v4.17 2018-04-15 12:27:58 -07:00
parisc parisc: Fix section mismatches 2018-05-02 21:47:35 +02:00
powerpc powerpc/kvm/booke: Fix altivec related build break 2018-04-27 16:36:03 +10:00
riscv drivers: base: cacheinfo: setup DT cache properties early 2018-05-17 17:27:49 +01:00
s390 s390: correct module section names for expoline code revert 2018-04-23 07:57:17 +02:00
sh Merge branch 'akpm' (patches from Andrew) 2018-04-14 08:50:50 -07:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2018-04-30 13:27:16 -07:00
um Merge git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2018-04-11 16:36:47 -07:00
unicore32 unicore32: turn flush_dcache_mmap_lock into a no-op 2018-04-11 10:28:39 -07:00
x86 KVM fixes for v4.17-rc4 2018-05-06 05:46:29 -10:00
xtensa mm: introduce MAP_FIXED_NOREPLACE 2018-04-11 10:28:38 -07:00
.gitignore
Kconfig kbuild: remove incremental linking option 2018-03-26 02:01:19 +09:00