diff options
| author | Maxim Mikityanskiy <maximmi@mellanox.com> | 2019-03-30 01:37:52 +0300 |
|---|---|---|
| committer | Saeed Mahameed <saeedm@mellanox.com> | 2019-04-02 22:49:37 +0300 |
| commit | bbf29f618e8c5bfd6efdad5fdc050a84bab795ab (patch) | |
| tree | 0f64a9d17640e1e9b083df0e547ac6c69e5deb34 /include | |
| parent | 38702cce547a74493687fd8bb925fbb5c3898ce3 (diff) | |
| download | linux-bbf29f618e8c5bfd6efdad5fdc050a84bab795ab.tar.xz | |
net/mlx5: Remove spinlock support from mlx5_write64
As there is no user of mlx5_write64 that passes a spinlock to
mlx5_write64, remove this functionality and simplify the function.
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/mlx5/cq.h | 2 | ||||
| -rw-r--r-- | include/linux/mlx5/doorbell.h | 31 |
2 files changed, 10 insertions, 23 deletions
diff --git a/include/linux/mlx5/cq.h b/include/linux/mlx5/cq.h index 612c8c2f2466..769326ea1d9b 100644 --- a/include/linux/mlx5/cq.h +++ b/include/linux/mlx5/cq.h @@ -170,7 +170,7 @@ static inline void mlx5_cq_arm(struct mlx5_core_cq *cq, u32 cmd, doorbell[0] = cpu_to_be32(sn << 28 | cmd | ci); doorbell[1] = cpu_to_be32(cq->cqn); - mlx5_write64(doorbell, uar_page + MLX5_CQ_DOORBELL, NULL); + mlx5_write64(doorbell, uar_page + MLX5_CQ_DOORBELL); } static inline void mlx5_cq_hold(struct mlx5_core_cq *cq) diff --git a/include/linux/mlx5/doorbell.h b/include/linux/mlx5/doorbell.h index 9ef3f9d00154..5c267707e1df 100644 --- a/include/linux/mlx5/doorbell.h +++ b/include/linux/mlx5/doorbell.h @@ -36,38 +36,25 @@ #define MLX5_BF_OFFSET 0x800 #define MLX5_CQ_DOORBELL 0x20 -#if BITS_PER_LONG == 64 /* Assume that we can just write a 64-bit doorbell atomically. s390 * actually doesn't have writeq() but S/390 systems don't even have * PCI so we won't worry about it. + * + * Note that the write is not atomic on 32-bit systems! In contrast to 64-bit + * ones, it requires proper locking. mlx5_write64 doesn't do any locking, so use + * it at your own discretion, protected by some kind of lock on 32 bits. + * + * TODO: use write{q,l}_relaxed() */ -static inline void mlx5_write64(__be32 val[2], void __iomem *dest, - spinlock_t *doorbell_lock) +static inline void mlx5_write64(__be32 val[2], void __iomem *dest) { +#if BITS_PER_LONG == 64 __raw_writeq(*(u64 *)val, dest); -} - #else - -/* Just fall back to a spinlock to protect the doorbell if - * BITS_PER_LONG is 32 -- there's no portable way to do atomic 64-bit - * MMIO writes. - */ - -static inline void mlx5_write64(__be32 val[2], void __iomem *dest, - spinlock_t *doorbell_lock) -{ - unsigned long flags; - - if (doorbell_lock) - spin_lock_irqsave(doorbell_lock, flags); __raw_writel((__force u32) val[0], dest); __raw_writel((__force u32) val[1], dest + 4); - if (doorbell_lock) - spin_unlock_irqrestore(doorbell_lock, flags); -} - #endif +} #endif /* MLX5_DOORBELL_H */ |