drivers: Remove explicit invocations of mmiowb()
mmiowb() is now implied by spin_unlock() on architectures that require it, so there is no reason to call it from driver code. This patch was generated using coccinelle: @mmiowb@ @@ - mmiowb(); and invoked as: $ for d in drivers include/linux/qed sound; do \ spatch --include-headers --sp-file mmiowb.cocci --dir $d --in-place; done NOTE: mmiowb() has only ever guaranteed ordering in conjunction with spin_unlock(). However, pairing each mmiowb() removal in this patch with the corresponding call to spin_unlock() is not at all trivial, so there is a small chance that this change may regress any drivers incorrectly relying on mmiowb() to order MMIO writes between CPUs using lock-free synchronisation. If you've ended up bisecting to this commit, you can reintroduce the mmiowb() calls using wmb() instead, which should restore the old behaviour on all architectures other than some esoteric ia64 systems. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
@@ -1338,7 +1338,6 @@ static inline u16 qed_sb_update_sb_idx(struct qed_sb_info *sb_info)
|
||||
}
|
||||
|
||||
/* Let SB update */
|
||||
mmiowb();
|
||||
return rc;
|
||||
}
|
||||
|
||||
@@ -1374,7 +1373,6 @@ static inline void qed_sb_ack(struct qed_sb_info *sb_info,
|
||||
/* Both segments (interrupts & acks) are written to same place address;
|
||||
* Need to guarantee all commands will be received (in-order) by HW.
|
||||
*/
|
||||
mmiowb();
|
||||
barrier();
|
||||
}
|
||||
|
||||
|
Reference in New Issue
Block a user