| Message ID | 1539947977-4686-1-git-send-email-avri.altman@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] block: Bundle together NONE and NOT_SET writehint types | expand |
On 10/19/18 5:19 AM, Avri Altman wrote: > There are 6 writehint types, but the size of the write_hints array > in the request queue is BLK_MAX_WRITE_HINTS = 5, > which causes the EXTREME type to be ignored when iterating > over the hints. > > We only have effectively 5 hints. > Bundle together NONE and NOT_SET, since they end up in the same > bucket on the driver side. > > fixes: f793dfd3f39a (blk-mq: expose write hints through debugfs) This isn't right, you can't just redefine the user API. Looking at the whole thing, I don't think there's a bug. We have 5 hints, as mentioned in my previous reply - 4 valid ones, and 1 none. If you look at the only current user of streams, NVMe, it already bundles NONE and NOT_SET into 0. Hence there's no bug.
diff --git a/fs/fcntl.c b/fs/fcntl.c index 4137d96..163cf5fd 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -261,7 +261,7 @@ static int f_getowner_uids(struct file *filp, unsigned long arg) static bool rw_hint_valid(enum rw_hint hint) { switch (hint) { - case RWF_WRITE_LIFE_NOT_SET: + /* RWF_WRITE_LIFE_NOT_SET = RWH_WRITE_LIFE_NONE */ case RWH_WRITE_LIFE_NONE: case RWH_WRITE_LIFE_SHORT: case RWH_WRITE_LIFE_MEDIUM: diff --git a/include/uapi/linux/fcntl.h b/include/uapi/linux/fcntl.h index 6448cdd..ff048f8 100644 --- a/include/uapi/linux/fcntl.h +++ b/include/uapi/linux/fcntl.h @@ -58,11 +58,11 @@ * used to clear any hints previously set. */ #define RWF_WRITE_LIFE_NOT_SET 0 -#define RWH_WRITE_LIFE_NONE 1 -#define RWH_WRITE_LIFE_SHORT 2 -#define RWH_WRITE_LIFE_MEDIUM 3 -#define RWH_WRITE_LIFE_LONG 4 -#define RWH_WRITE_LIFE_EXTREME 5 +#define RWH_WRITE_LIFE_NONE RWF_WRITE_LIFE_NOT_SET +#define RWH_WRITE_LIFE_SHORT 1 +#define RWH_WRITE_LIFE_MEDIUM 2 +#define RWH_WRITE_LIFE_LONG 3 +#define RWH_WRITE_LIFE_EXTREME 4 /* * Types of directory notifications that may be requested. diff --git a/tools/include/uapi/linux/fcntl.h b/tools/include/uapi/linux/fcntl.h index 6448cdd..ff048f8 100644 --- a/tools/include/uapi/linux/fcntl.h +++ b/tools/include/uapi/linux/fcntl.h @@ -58,11 +58,11 @@ * used to clear any hints previously set. */ #define RWF_WRITE_LIFE_NOT_SET 0 -#define RWH_WRITE_LIFE_NONE 1 -#define RWH_WRITE_LIFE_SHORT 2 -#define RWH_WRITE_LIFE_MEDIUM 3 -#define RWH_WRITE_LIFE_LONG 4 -#define RWH_WRITE_LIFE_EXTREME 5 +#define RWH_WRITE_LIFE_NONE RWF_WRITE_LIFE_NOT_SET +#define RWH_WRITE_LIFE_SHORT 1 +#define RWH_WRITE_LIFE_MEDIUM 2 +#define RWH_WRITE_LIFE_LONG 3 +#define RWH_WRITE_LIFE_EXTREME 4 /* * Types of directory notifications that may be requested.
There are 6 writehint types, but the size of the write_hints array in the request queue is BLK_MAX_WRITE_HINTS = 5, which causes the EXTREME type to be ignored when iterating over the hints. We only have effectively 5 hints. Bundle together NONE and NOT_SET, since they end up in the same bucket on the driver side. fixes: f793dfd3f39a (blk-mq: expose write hints through debugfs) v1->v2: Bundle together NONE and NOT_SET, instead of making the write_hints array of the request queue larger. Change the commit title accordingly. Signed-off-by: Avri Altman <avri.altman@wdc.com> --- fs/fcntl.c | 2 +- include/uapi/linux/fcntl.h | 10 +++++----- tools/include/uapi/linux/fcntl.h | 10 +++++----- 3 files changed, 11 insertions(+), 11 deletions(-)