[PATCH v4 6/7] RISC-V: Move to queued RW locks
Palmer Dabbelt
palmer at rivosinc.com
Sat Apr 30 08:36:25 PDT 2022
From: Palmer Dabbelt <palmer at rivosinc.com>
Now that we have fair spinlocks we can use the generic queued rwlocks,
so we might as well do so.
Signed-off-by: Palmer Dabbelt <palmer at rivosinc.com>
---
arch/riscv/Kconfig | 1 +
arch/riscv/include/asm/Kbuild | 2 +
arch/riscv/include/asm/spinlock.h | 99 -------------------------
arch/riscv/include/asm/spinlock_types.h | 24 ------
4 files changed, 3 insertions(+), 123 deletions(-)
delete mode 100644 arch/riscv/include/asm/spinlock.h
delete mode 100644 arch/riscv/include/asm/spinlock_types.h
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 00fd9c548f26..f8a55d94016d 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -39,6 +39,7 @@ config RISCV
select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
select ARCH_SUPPORTS_HUGETLBFS if MMU
select ARCH_USE_MEMTEST
+ select ARCH_USE_QUEUED_RWLOCKS
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
select ARCH_WANT_FRAME_POINTERS
select ARCH_WANT_GENERAL_HUGETLB
diff --git a/arch/riscv/include/asm/Kbuild b/arch/riscv/include/asm/Kbuild
index c3f229ae8033..504f8b7e72d4 100644
--- a/arch/riscv/include/asm/Kbuild
+++ b/arch/riscv/include/asm/Kbuild
@@ -3,6 +3,8 @@ generic-y += early_ioremap.h
generic-y += flat.h
generic-y += kvm_para.h
generic-y += parport.h
+generic-y += spinlock.h
+generic-y += spinlock_types.h
generic-y += qrwlock.h
generic-y += qrwlock_types.h
generic-y += user.h
diff --git a/arch/riscv/include/asm/spinlock.h b/arch/riscv/include/asm/spinlock.h
deleted file mode 100644
index 88a4d5d0d98a..000000000000
--- a/arch/riscv/include/asm/spinlock.h
+++ /dev/null
@@ -1,99 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2015 Regents of the University of California
- * Copyright (C) 2017 SiFive
- */
-
-#ifndef _ASM_RISCV_SPINLOCK_H
-#define _ASM_RISCV_SPINLOCK_H
-
-/* This is horible, but the whole file is going away in the next commit. */
-#define __ASM_GENERIC_QRWLOCK_H
-
-#include <linux/kernel.h>
-#include <asm/current.h>
-#include <asm/fence.h>
-#include <asm-generic/spinlock.h>
-
-static inline void arch_read_lock(arch_rwlock_t *lock)
-{
- int tmp;
-
- __asm__ __volatile__(
- "1: lr.w %1, %0\n"
- " bltz %1, 1b\n"
- " addi %1, %1, 1\n"
- " sc.w %1, %1, %0\n"
- " bnez %1, 1b\n"
- RISCV_ACQUIRE_BARRIER
- : "+A" (lock->lock), "=&r" (tmp)
- :: "memory");
-}
-
-static inline void arch_write_lock(arch_rwlock_t *lock)
-{
- int tmp;
-
- __asm__ __volatile__(
- "1: lr.w %1, %0\n"
- " bnez %1, 1b\n"
- " li %1, -1\n"
- " sc.w %1, %1, %0\n"
- " bnez %1, 1b\n"
- RISCV_ACQUIRE_BARRIER
- : "+A" (lock->lock), "=&r" (tmp)
- :: "memory");
-}
-
-static inline int arch_read_trylock(arch_rwlock_t *lock)
-{
- int busy;
-
- __asm__ __volatile__(
- "1: lr.w %1, %0\n"
- " bltz %1, 1f\n"
- " addi %1, %1, 1\n"
- " sc.w %1, %1, %0\n"
- " bnez %1, 1b\n"
- RISCV_ACQUIRE_BARRIER
- "1:\n"
- : "+A" (lock->lock), "=&r" (busy)
- :: "memory");
-
- return !busy;
-}
-
-static inline int arch_write_trylock(arch_rwlock_t *lock)
-{
- int busy;
-
- __asm__ __volatile__(
- "1: lr.w %1, %0\n"
- " bnez %1, 1f\n"
- " li %1, -1\n"
- " sc.w %1, %1, %0\n"
- " bnez %1, 1b\n"
- RISCV_ACQUIRE_BARRIER
- "1:\n"
- : "+A" (lock->lock), "=&r" (busy)
- :: "memory");
-
- return !busy;
-}
-
-static inline void arch_read_unlock(arch_rwlock_t *lock)
-{
- __asm__ __volatile__(
- RISCV_RELEASE_BARRIER
- " amoadd.w x0, %1, %0\n"
- : "+A" (lock->lock)
- : "r" (-1)
- : "memory");
-}
-
-static inline void arch_write_unlock(arch_rwlock_t *lock)
-{
- smp_store_release(&lock->lock, 0);
-}
-
-#endif /* _ASM_RISCV_SPINLOCK_H */
diff --git a/arch/riscv/include/asm/spinlock_types.h b/arch/riscv/include/asm/spinlock_types.h
deleted file mode 100644
index f2f9b5d7120d..000000000000
--- a/arch/riscv/include/asm/spinlock_types.h
+++ /dev/null
@@ -1,24 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2015 Regents of the University of California
- */
-
-#ifndef _ASM_RISCV_SPINLOCK_TYPES_H
-#define _ASM_RISCV_SPINLOCK_TYPES_H
-
-/* This is horible, but the whole file is going away in the next commit. */
-#define __ASM_GENERIC_QRWLOCK_TYPES_H
-
-#ifndef __LINUX_SPINLOCK_TYPES_RAW_H
-# error "please don't include this file directly"
-#endif
-
-#include <asm-generic/spinlock_types.h>
-
-typedef struct {
- volatile unsigned int lock;
-} arch_rwlock_t;
-
-#define __ARCH_RW_LOCK_UNLOCKED { 0 }
-
-#endif /* _ASM_RISCV_SPINLOCK_TYPES_H */
--
2.34.1
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