| Message ID | 20241210194722.1905732-1-kbusch@meta.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | block write streams with nvme fdp | expand |
On Tue, Dec 10, 2024 at 11:47:11AM -0800, Keith Busch wrote:
> Changes from v12:
The changes looks good to me. I'll ty to send out an API for querying
the paramters in the next so that we don't merge the granularity as dead
code, but I'll need a bit more time to also write proper tests and
stuff. For that it probably makes sense to expose these streams using
null_blk so that we can actually have a block test. If someone feels
like speeding things up I'd also be happy for someone else to take
that work.
> > unsigned int max_open_zones; > unsigned int max_active_zones; > @@ -1249,6 +1250,12 @@ static inline unsigned short bdev_max_write_streams(struct block_device *bdev) > return bdev_limits(bdev)->max_write_streams; > } > > +static inline unsigned int > +bdev_write_stream_granularity(struct block_device *bdev) is this referenced anywhere? I see that Nitesh mentioned something similar also previously > +{ > + return bdev_limits(bdev)->write_stream_granularity; > +} > + > static inline unsigned queue_logical_block_size(const struct request_queue *q) > { > return q->limits.logical_block_size;
On 12/11/2024 12:43 PM, Christoph Hellwig wrote: > The changes looks good to me. I'll ty to send out an API for querying > the paramters in the next so that we don't merge the granularity as dead > code What do you have in mind for this API. New fcntl or ioctl? With ability limited to querying only or....
On Thu, Dec 12, 2024 at 11:21:07AM +0530, Kanchan Joshi wrote: > On 12/11/2024 12:43 PM, Christoph Hellwig wrote: > > The changes looks good to me. I'll ty to send out an API for querying > > the paramters in the next so that we don't merge the granularity as dead > > code > > What do you have in mind for this API. New fcntl or ioctl? > With ability limited to querying only or.... Yes, new fcntl or ioctl, query the number of streams and (nominal) stream granularity as a start. There is a few other things that might be useful: - check if the size is just nominal or not, aka if the device can shorten it. FDP currently allows for that, but given that notifications for that are out of bounds it makes a complete mess of software actually trying to use it for more than simple hot/cold separation like cachelib, so we find a way to query that in the spec. - reporting of the remaining capacity per stream, although I'm not sure if that should be in the same ioctl/fcntl, or better done using a separate interface that has the stream number as input and the capacity as out, which would seem a lot simpler
From: Keith Busch <kbusch@kernel.org> Previous discussion threads: v12: https://lore.kernel.org/linux-nvme/20241206221801.790690-1-kbusch@meta.com/T/#u v11: https://lore.kernel.org/linux-nvme/20241206015308.3342386-1-kbusch@meta.com/T/#u Changes from v12: - Removed statx. We need additional time to consider the best way to expose these attributes. Until then, applications can fallback to the sysfs block attribute to query write stream settings. - More verbose logging on error. - Added reviews. - Explicitly clear the return value to 0 for unsupported or unrecognized FDP configs; while it's not technically needed (it's already 0 in these paths), it makes it clear that a non-error return wasn't an accidental oversight. - Fixed the compiler warnings from unitialized variable; switched the do-while to a more clear for-loop. - Fixed long-line wrapping - Memory leak when cleaning up the namespace head. - Don't rescan FDP configuration if we successfully set it up before. The namespaces' FDP configuration is static. - Better function name querying the size granularity of the FDP reclaim unit. Christoph Hellwig (7): fs: add a write stream field to the kiocb block: add a bi_write_stream field block: introduce a write_stream_granularity queue limit block: expose write streams for block device nodes nvme: add a nvme_get_log_lsi helper nvme: pass a void pointer to nvme_get/set_features for the result nvme: add FDP definitions Keith Busch (4): block: introduce max_write_streams queue limit io_uring: enable per-io write streams nvme: register fdp parameters with the block layer nvme: use fdp streams if write stream is provided Documentation/ABI/stable/sysfs-block | 15 +++ block/bio.c | 2 + block/blk-crypto-fallback.c | 1 + block/blk-merge.c | 4 + block/blk-sysfs.c | 6 + block/bounce.c | 1 + block/fops.c | 23 ++++ drivers/nvme/host/core.c | 186 ++++++++++++++++++++++++++- drivers/nvme/host/nvme.h | 7 +- include/linux/blk_types.h | 1 + include/linux/blkdev.h | 16 +++ include/linux/fs.h | 1 + include/linux/nvme.h | 77 +++++++++++ include/uapi/linux/io_uring.h | 4 + io_uring/io_uring.c | 2 + io_uring/rw.c | 1 + 16 files changed, 341 insertions(+), 6 deletions(-)