summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
authorWill Deacon <will.deacon@arm.com>2019-02-22 15:59:59 +0300
committerWill Deacon <will.deacon@arm.com>2019-04-08 13:59:47 +0300
commit60ca1e5a200cd294a12907fa36dece4241db4ab8 (patch)
tree2dcd2e666b2b1cad4ce0c80f263cb122bdeebc1b /include
parentfdcd06a8ab775cbe716ff893372bed580e4c8a1c (diff)
downloadlinux-60ca1e5a200cd294a12907fa36dece4241db4ab8.tar.xz
mmiowb: Hook up mmiowb helpers to spinlocks and generic I/O accessors
Removing explicit calls to mmiowb() from driver code means that we must now call into the generic mmiowb_spin_{lock,unlock}() functions from the core spinlock code. In order to elide barriers following critical sections without any I/O writes, we also hook into the asm-generic I/O routines. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'include')
-rw-r--r--include/asm-generic/io.h3
-rw-r--r--include/linux/spinlock.h11
2 files changed, 12 insertions, 2 deletions
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index 303871651f8a..bc490a746602 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -19,6 +19,7 @@
#include <asm-generic/iomap.h>
#endif
+#include <asm/mmiowb.h>
#include <asm-generic/pci_iomap.h>
#ifndef mmiowb
@@ -49,7 +50,7 @@
/* serialize device access against a spin_unlock, usually handled there. */
#ifndef __io_aw
-#define __io_aw() barrier()
+#define __io_aw() mmiowb_set_pending()
#endif
#ifndef __io_pbw
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index e089157dcf97..ed7c4d6b8235 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -57,6 +57,7 @@
#include <linux/stringify.h>
#include <linux/bottom_half.h>
#include <asm/barrier.h>
+#include <asm/mmiowb.h>
/*
@@ -178,6 +179,7 @@ static inline void do_raw_spin_lock(raw_spinlock_t *lock) __acquires(lock)
{
__acquire(lock);
arch_spin_lock(&lock->raw_lock);
+ mmiowb_spin_lock();
}
#ifndef arch_spin_lock_flags
@@ -189,15 +191,22 @@ do_raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long *flags) __acquires(lo
{
__acquire(lock);
arch_spin_lock_flags(&lock->raw_lock, *flags);
+ mmiowb_spin_lock();
}
static inline int do_raw_spin_trylock(raw_spinlock_t *lock)
{
- return arch_spin_trylock(&(lock)->raw_lock);
+ int ret = arch_spin_trylock(&(lock)->raw_lock);
+
+ if (ret)
+ mmiowb_spin_lock();
+
+ return ret;
}
static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
{
+ mmiowb_spin_unlock();
arch_spin_unlock(&lock->raw_lock);
__release(lock);
}