ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 12:43:29 +02:00
Code Issues Packages Projects Releases Wiki Activity

mmiowb: Hook up mmiowb helpers to spinlocks and generic I/O accessors

Browse Source 
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>
This commit is contained in:
Will Deacon
2019-02-22 12:59:59 +00:00
parent fdcd06a8ab
commit 60ca1e5a20
3 changed files with 17 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
kernel/locking/spinlock_debug.c
View File

@@ -111,6 +111,7 @@ void do_raw_spin_lock(raw_spinlock_t *lock)
{
debug_spin_lock_before(lock);
arch_spin_lock(&lock->raw_lock);
mmiowb_spin_lock();
debug_spin_lock_after(lock);
}
@@ -118,8 +119,10 @@ int do_raw_spin_trylock(raw_spinlock_t *lock)
{
int ret = arch_spin_trylock(&lock->raw_lock);
if (ret)
if (ret) {
mmiowb_spin_lock();
debug_spin_lock_after(lock);
}
#ifndef CONFIG_SMP
/*
* Must not happen on UP:
@@ -131,6 +134,7 @@ int do_raw_spin_trylock(raw_spinlock_t *lock)
void do_raw_spin_unlock(raw_spinlock_t *lock)
{
mmiowb_spin_unlock();
debug_spin_unlock(lock);
arch_spin_unlock(&lock->raw_lock);
}