On Tue, 15 May 2018 15:51:20 PDT (-0700), [email protected] wrote:
The next patch in this series introduces a call to cmpxchg64()
in the block layer core for those architectures on which this
functionality is available. Make it possible to test whether
cmpxchg64() is available by introducing CONFIG_ARCH_HAVE_CMPXCHG64.
Signed-off-by: Bart Van Assche <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: "James E.J. Bottomley" <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Chris Zankel <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Jonathan Corbet <[email protected]>
---
.../features/locking/cmpxchg64/arch-support.txt | 33 ++++++++++++++++++++++
arch/Kconfig | 3 ++
arch/alpha/Kconfig | 1 +
arch/arm/Kconfig | 1 +
arch/arm64/Kconfig | 1 +
arch/ia64/Kconfig | 1 +
arch/m68k/Kconfig | 1 +
arch/mips/Kconfig | 1 +
arch/parisc/Kconfig | 1 +
arch/powerpc/Kconfig | 1 +
arch/riscv/Kconfig | 1 +
arch/s390/Kconfig | 1 +
arch/sparc/Kconfig | 1 +
arch/x86/Kconfig | 1 +
arch/xtensa/Kconfig | 1 +
15 files changed, 49 insertions(+)
create mode 100644 Documentation/features/locking/cmpxchg64/arch-support.txt
[...]
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -8,6 +8,7 @@ config RISCV
select OF
select OF_EARLY_FLATTREE
select OF_IRQ
+ select ARCH_HAVE_CMPXCHG64
select ARCH_WANT_FRAME_POINTERS
select CLONE_BACKWARDS
select COMMON_CLK
If I understand correctly, we should only have ARCH_HAVE_CMPXCHG64 on 64-bit
RISC-V systems so this should look something like
select ARCH_HAVE_CMPXCHG64 if 64BIT
Of course, the RV32I port is broken right now so it's not a big deal, but we're
working through making it less broken...
