diff mbox series

[v2] riscv: hwprobe: export Zihintpause ISA extension

Message ID 20240221083108.1235311-1-cleger@rivosinc.com (mailing list archive)
State Accepted
Commit 63f93a3ca891fd90353cf81f5d2fc4cbc3508f1a
Headers show
Series [v2] riscv: hwprobe: export Zihintpause ISA extension | expand

Checks

Context Check Description
conchuod/vmtest-for-next-PR success PR summary
conchuod/patch-1-test-1 success .github/scripts/patches/tests/build_rv32_defconfig.sh
conchuod/patch-1-test-2 success .github/scripts/patches/tests/build_rv64_clang_allmodconfig.sh
conchuod/patch-1-test-3 success .github/scripts/patches/tests/build_rv64_gcc_allmodconfig.sh
conchuod/patch-1-test-4 success .github/scripts/patches/tests/build_rv64_nommu_k210_defconfig.sh
conchuod/patch-1-test-5 success .github/scripts/patches/tests/build_rv64_nommu_virt_defconfig.sh
conchuod/patch-1-test-6 warning .github/scripts/patches/tests/checkpatch.sh
conchuod/patch-1-test-7 success .github/scripts/patches/tests/dtb_warn_rv64.sh
conchuod/patch-1-test-8 success .github/scripts/patches/tests/header_inline.sh
conchuod/patch-1-test-9 success .github/scripts/patches/tests/kdoc.sh
conchuod/patch-1-test-10 success .github/scripts/patches/tests/module_param.sh
conchuod/patch-1-test-11 success .github/scripts/patches/tests/verify_fixes.sh
conchuod/patch-1-test-12 success .github/scripts/patches/tests/verify_signedoff.sh

Commit Message

Clément Léger Feb. 21, 2024, 8:31 a.m. UTC
Export the Zihintpause ISA extension through hwprobe which allows using
"pause" instructions. Some userspace applications (OpenJDK for
instance) uses this to handle some locking back-off.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
---
v2:
 - Fix typo "commit commit"
 - Add Atish Reviewed-by:
 - Link to v1: https://lore.kernel.org/lkml/20240219154905.528301-1-cleger@rivosinc.com/
---
 Documentation/arch/riscv/hwprobe.rst  | 4 ++++
 arch/riscv/include/uapi/asm/hwprobe.h | 1 +
 arch/riscv/kernel/sys_hwprobe.c       | 1 +
 3 files changed, 6 insertions(+)

Comments

patchwork-bot+linux-riscv@kernel.org April 28, 2024, 10 p.m. UTC | #1
Hello:

This patch was applied to riscv/linux.git (for-next)
by Palmer Dabbelt <palmer@rivosinc.com>:

On Wed, 21 Feb 2024 09:31:06 +0100 you wrote:
> Export the Zihintpause ISA extension through hwprobe which allows using
> "pause" instructions. Some userspace applications (OpenJDK for
> instance) uses this to handle some locking back-off.
> 
> Signed-off-by: Clément Léger <cleger@rivosinc.com>
> Reviewed-by: Atish Patra <atishp@rivosinc.com>
> 
> [...]

Here is the summary with links:
  - [v2] riscv: hwprobe: export Zihintpause ISA extension
    https://git.kernel.org/riscv/c/63f93a3ca891

You are awesome, thank you!
diff mbox series

Patch

diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index b2bcc9eed9aa..204cd4433af5 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -188,6 +188,10 @@  The following keys are defined:
        manual starting from commit 95cf1f9 ("Add changes requested by Ved
        during signoff")
 
+  * :c:macro:`RISCV_HWPROBE_EXT_ZIHINTPAUSE`: The Zihintpause extension is
+       supported as defined in the RISC-V ISA manual starting from commit
+       d8ab5c78c207 ("Zihintpause is ratified").
+
 * :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance
   information about the selected set of processors.
 
diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h
index 9f2a8e3ff204..31c570cbd1c5 100644
--- a/arch/riscv/include/uapi/asm/hwprobe.h
+++ b/arch/riscv/include/uapi/asm/hwprobe.h
@@ -59,6 +59,7 @@  struct riscv_hwprobe {
 #define		RISCV_HWPROBE_EXT_ZTSO		(1ULL << 33)
 #define		RISCV_HWPROBE_EXT_ZACAS		(1ULL << 34)
 #define		RISCV_HWPROBE_EXT_ZICOND	(1ULL << 35)
+#define		RISCV_HWPROBE_EXT_ZIHINTPAUSE	(1ULL << 36)
 #define RISCV_HWPROBE_KEY_CPUPERF_0	5
 #define		RISCV_HWPROBE_MISALIGNED_UNKNOWN	(0 << 0)
 #define		RISCV_HWPROBE_MISALIGNED_EMULATED	(1 << 0)
diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index a7c56b41efd2..1008d25880e1 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -111,6 +111,7 @@  static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 		EXT_KEY(ZTSO);
 		EXT_KEY(ZACAS);
 		EXT_KEY(ZICOND);
+		EXT_KEY(ZIHINTPAUSE);
 
 		if (has_vector()) {
 			EXT_KEY(ZVBB);