diff options
| author | Will Deacon <will.deacon@arm.com> | 2019-02-22 13:37:21 +0000 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2019-04-08 12:00:28 +0100 |
| commit | 346e91ee090b07da8d15e36bc3169ddea6968713 (patch) | |
| tree | 8ec14892fbf565049c4ffa4a23d628514da4e991 /arch/mips/include/asm | |
| parent | e9e8543fecd2e1ca53616ba82fbd55a25cd2ab8a (diff) | |
| download | linux-346e91ee090b07da8d15e36bc3169ddea6968713.tar.bz2 | |
mips/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
The mmiowb() macro is horribly difficult to use and drivers will continue
to work most of the time if they omit a call when it is required.
Rather than rely on driver authors getting this right, push mmiowb() into
arch_spin_unlock() for mips. If this is deemed to be a performance issue,
a subsequent optimisation could make use of ARCH_HAS_MMIOWB to elide
the barrier in cases where no I/O writes were performed inside the
critical section.
Acked-by: Paul Burton <paul.burton@mips.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/mips/include/asm')
| -rw-r--r-- | arch/mips/include/asm/Kbuild | 1 | ||||
| -rw-r--r-- | arch/mips/include/asm/io.h | 3 | ||||
| -rw-r--r-- | arch/mips/include/asm/mmiowb.h | 11 | ||||
| -rw-r--r-- | arch/mips/include/asm/spinlock.h | 15 |
4 files changed, 26 insertions, 4 deletions
diff --git a/arch/mips/include/asm/Kbuild b/arch/mips/include/asm/Kbuild index bf39c2253ec8..87b86cdf126a 100644 --- a/arch/mips/include/asm/Kbuild +++ b/arch/mips/include/asm/Kbuild @@ -12,7 +12,6 @@ generic-y += irq_work.h generic-y += local64.h generic-y += mcs_spinlock.h generic-y += mm-arch-hooks.h -generic-y += mmiowb.h generic-y += msi.h generic-y += parport.h generic-y += percpu.h diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h index 845fbbc7a2e3..29997e42480e 100644 --- a/arch/mips/include/asm/io.h +++ b/arch/mips/include/asm/io.h @@ -102,9 +102,6 @@ static inline void set_io_port_base(unsigned long base) #define iobarrier_w() wmb() #define iobarrier_sync() iob() -/* Some callers use this older API instead. */ -#define mmiowb() iobarrier_w() - /* * virt_to_phys - map virtual addresses to physical * @address: address to remap diff --git a/arch/mips/include/asm/mmiowb.h b/arch/mips/include/asm/mmiowb.h new file mode 100644 index 000000000000..a40824e3ef8e --- /dev/null +++ b/arch/mips/include/asm/mmiowb.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_MMIOWB_H +#define _ASM_MMIOWB_H + +#include <asm/io.h> + +#define mmiowb() iobarrier_w() + +#include <asm-generic/mmiowb.h> + +#endif /* _ASM_MMIOWB_H */ diff --git a/arch/mips/include/asm/spinlock.h b/arch/mips/include/asm/spinlock.h index ee81297d9117..8a88eb265516 100644 --- a/arch/mips/include/asm/spinlock.h +++ b/arch/mips/include/asm/spinlock.h @@ -11,6 +11,21 @@ #include <asm/processor.h> #include <asm/qrwlock.h> + +#include <asm-generic/qspinlock_types.h> + +#define queued_spin_unlock queued_spin_unlock +/** + * queued_spin_unlock - release a queued spinlock + * @lock : Pointer to queued spinlock structure + */ +static inline void queued_spin_unlock(struct qspinlock *lock) +{ + /* This could be optimised with ARCH_HAS_MMIOWB */ + mmiowb(); + smp_store_release(&lock->locked, 0); +} + #include <asm/qspinlock.h> #endif /* _ASM_SPINLOCK_H */ |