Re: [RFC PATCH] block: add meaningful macro for flush op flags
From: Coly Li <hidden>
Date: 2023-05-14 11:11:42
Also in:
dm-devel, linux-bcache, linux-block, linux-nvme, linux-scsi, target-devel
2023年5月12日 10:07，Chaitanya Kulkarni [off-list ref] 写道： Flush requests are implemented as REQ_OP_WRITE + REQ_OP_PREFLUSH combination and not REQ_OP_FLUSH + REQ_PREFLUSH combination. This unclear nature has lead to the confusion and bugs in the code for block drivers causing more work for testing, reviews and fixes :- 1. https://lore.kernel.org/all/ZFHgefWofVt24tRl@infradead.org/ (local) 2. https://marc.info/?l=linux-block&m=168386364026498&w=2 Add a macro (name can me more meaningful) with a meaningful comment clearing the confusion and replace the REQ_OP_WRITE | REQ_PREFLUSH with the new macro name that also saves code repetation. Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
quoted hunk ↗ jump to hunk
--- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h@@ -455,6 +455,13 @@ enum req_flag_bits {#define REQ_NOMERGE_FLAGS \ (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA) +/* + * Flush requests are implemented as REQ_OP_WRITE + REQ_OP_PREFLUSH combination + * and not REQ_OP_FLUSH + REQ_PREFLUSH combination. + */ + +#define REQ_FLUSH_OPF (REQ_OP_WRITE | REQ_PREFLUSH) + enum stat_group { STAT_READ, STAT_WRITE, --
Personally I like current explicit way, it is simpler than an extra macro. This is just my own points, FYI. Thanks. Coly Li