| Message ID | 1282382688-5786-1-git-send-email-akinobu.mita@gmail.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Akinobu Mita <akinobu.mita@gmail.com> Date: Sat, 21 Aug 2010 18:24:48 +0900 > Use bitmap_set() and bitmap_clear() > > Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Unlike loops calling set_bit() and clear_bit(), bitmap_set() and bitmap_clear() are not atomic. Are you sure this is ok here? -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
2010/8/23 David Miller <davem@davemloft.net>: > From: Akinobu Mita <akinobu.mita@gmail.com> > Date: Sat, 21 Aug 2010 18:24:48 +0900 > >> Use bitmap_set() and bitmap_clear() >> >> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> > > Unlike loops calling set_bit() and clear_bit(), bitmap_set() and > bitmap_clear() are not atomic. > > Are you sure this is ok here? > I think this ok. Because the bitmap region is searched by bitmap_find_next_zero_area() which cannot be atomic and setting and clearing the bitmap region is protected by bitmap->lock (except for initialization of the bitmap in mlx4_bitmap_init). This change should be done when I submitted commit 43ff8b60853793fb0155b3e465739d2170c3aa2f ("mlx4: use bitmap_find_next_zero_area") at the same time. I'll recheck this is ok and update the commit message for this change, then resubmit the patch. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Akinobu Mita <akinobu.mita@gmail.com> Date: Mon, 23 Aug 2010 13:21:55 +0900 > I'll recheck this is ok and update the commit message for this change, > then resubmit the patch. Ok, thank you. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/mlx4/alloc.c b/drivers/net/mlx4/alloc.c index 8c85156..76595bd 100644 --- a/drivers/net/mlx4/alloc.c +++ b/drivers/net/mlx4/alloc.c @@ -74,7 +74,7 @@ void mlx4_bitmap_free(struct mlx4_bitmap *bitmap, u32 obj) u32 mlx4_bitmap_alloc_range(struct mlx4_bitmap *bitmap, int cnt, int align) { - u32 obj, i; + u32 obj; if (likely(cnt == 1 && align == 1)) return mlx4_bitmap_alloc(bitmap); @@ -91,8 +91,7 @@ u32 mlx4_bitmap_alloc_range(struct mlx4_bitmap *bitmap, int cnt, int align) } if (obj < bitmap->max) { - for (i = 0; i < cnt; i++) - set_bit(obj + i, bitmap->table); + bitmap_set(bitmap->table, obj, cnt); if (obj == bitmap->last) { bitmap->last = (obj + cnt); if (bitmap->last >= bitmap->max) @@ -109,13 +108,10 @@ u32 mlx4_bitmap_alloc_range(struct mlx4_bitmap *bitmap, int cnt, int align) void mlx4_bitmap_free_range(struct mlx4_bitmap *bitmap, u32 obj, int cnt) { - u32 i; - obj &= bitmap->max + bitmap->reserved_top - 1; spin_lock(&bitmap->lock); - for (i = 0; i < cnt; i++) - clear_bit(obj + i, bitmap->table); + bitmap_clear(bitmap->table, obj, cnt); bitmap->last = min(bitmap->last, obj); bitmap->top = (bitmap->top + bitmap->max + bitmap->reserved_top) & bitmap->mask; @@ -125,8 +121,6 @@ void mlx4_bitmap_free_range(struct mlx4_bitmap *bitmap, u32 obj, int cnt) int mlx4_bitmap_init(struct mlx4_bitmap *bitmap, u32 num, u32 mask, u32 reserved_bot, u32 reserved_top) { - int i; - /* num must be a power of 2 */ if (num != roundup_pow_of_two(num)) return -EINVAL; @@ -142,8 +136,7 @@ int mlx4_bitmap_init(struct mlx4_bitmap *bitmap, u32 num, u32 mask, if (!bitmap->table) return -ENOMEM; - for (i = 0; i < reserved_bot; ++i) - set_bit(i, bitmap->table); + bitmap_set(bitmap->table, 0, reserved_bot); return 0; }
Use bitmap_set() and bitmap_clear() Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Roland Dreier <rolandd@cisco.com> Cc: netdev@vger.kernel.org Cc: "David S. Miller" <davem@davemloft.net> --- drivers/net/mlx4/alloc.c | 15 ++++----------- 1 files changed, 4 insertions(+), 11 deletions(-)