Re: [PATCH 11/12]Remove defines of DMA_XXBIT_MASK micro

Ingo Molnar wrote:

* Yang Hongyang [off-list ref] wrote:

quoted

Remove defines of DMA_XXBIT_MASK micro

Signed-off-by: Yang Hongyang<redacted>

---
 include/linux/dma-mapping.h |   20 +-------------------
 1 files changed, 1 insertions(+), 19 deletions(-)

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index f238c7e..70f9c63 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h

@@ -13,27 +13,9 @@ enum dma_data_direction {
 	DMA_NONE = 3,
 };
 
+/*use DMA_BIT_MASK(n) within your driver instead of DMA_xxBIT_MASK*/
 #define DMA_BIT_MASK(n)	(((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
 
-/*
- * NOTE: do not use the below macros in new code and do not add new definitions
- * here.
- *
- * Instead, just open-code DMA_BIT_MASK(n) within your driver
- */
-#define DMA_64BIT_MASK	DMA_BIT_MASK(64)
-#define DMA_48BIT_MASK	DMA_BIT_MASK(48)
-#define DMA_47BIT_MASK	DMA_BIT_MASK(47)
-#define DMA_40BIT_MASK	DMA_BIT_MASK(40)
-#define DMA_39BIT_MASK	DMA_BIT_MASK(39)
-#define DMA_35BIT_MASK	DMA_BIT_MASK(35)
-#define DMA_32BIT_MASK	DMA_BIT_MASK(32)
-#define DMA_31BIT_MASK	DMA_BIT_MASK(31)
-#define DMA_30BIT_MASK	DMA_BIT_MASK(30)
-#define DMA_29BIT_MASK	DMA_BIT_MASK(29)
-#define DMA_28BIT_MASK	DMA_BIT_MASK(28)
-#define DMA_24BIT_MASK	DMA_BIT_MASK(24)

Looks good beyond the s/micro/macro typo fix, but i'd suggest to 
keep these old defines for one more kernel cycle, then do a 
final removal of all remaining uses, in a single patch.

That way we'll save ourselves from quite a bit of unnecessary 
build breakages (as your patchset shows there's still a lot of 
users of the old macros), as these definitions get moved around, 
reintroduced, etc.

Conflict resolution becomes easier as well - if such a patch 
conflicts with some ongoing work then we can by avoid the 
conflict by just dropping that hunk and delaying that particular 
conversion to the 'final' stage.

	Ingo

That's a good idea,Seems it's nessary to keep these old
defines.
I will resend the patch with s/micro/macro typo fix and keep
these old defines,Thanks Ingo!~


-- 
Regards
Yang Hongyang