- 20 Oct, 2017 3 commits
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Chaitanya Kulkarni authored
This adds SGL support for NVMe PCIe driver, based on an earlier patch from Rajiv Shanmugam Madeswaran <smrajiv15 at gmail.com>. This patch refactors the original code and adds new module parameter sgl_threshold to determine whether to use SGL or PRP for IOs. The usage of SGLs is controlled by the sgl_threshold module parameter, which allows to conditionally use SGLs if average request segment size (avg_seg_size) is greater than sgl_threshold. In the original patch, the decision of using SGLs was dependent only on the IO size, with the new approach we consider not only IO size but also the number of physical segments present in the IO. We calculate avg_seg_size based on request payload bytes and number of physical segments present in the request. For e.g.:- 1. blk_rq_nr_phys_segments = 2 blk_rq_payload_bytes = 8k avg_seg_size = 4K use sgl if avg_seg_size >= sgl_threshold. 2. blk_rq_nr_phys_segments = 2 blk_rq_payload_bytes = 64k avg_seg_size = 32K use sgl if avg_seg_size >= sgl_threshold. 3. blk_rq_nr_phys_segments = 16 blk_rq_payload_bytes = 64k avg_seg_size = 4K use sgl if avg_seg_size >= sgl_threshold. Signed-off-by:
Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by:
Keith Busch <keith.busch@intel.com> Reviewed-by:
Sagi Grimberg <sagi@grimberg.me> Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Christoph Hellwig authored
Switch to the ida_simple_* helpers instead of opencoding them. Signed-off-by:
Johannes Thumshirn <jthumshirn@suse.de>
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Roy Shterman authored
In case we disable namespaces which has the nsid like subsystem max_nsid we need to search for the next largest nsid in this subsystem. If the subsystem don't has more namespaces we set it to 0, else we take nsid from the last namespace in namespaces list because the list is sorted while inserting. Reviewed-by:
Max Gurtovoy <maxg@mellanox.com> Reviewed-by:
Roy Shterman <roys@lightbitslabs.com> Reviewed-by:
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- 19 Oct, 2017 4 commits
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Israel Rukshin authored
This flag is useful for admin queues that aren't used for normal IO. Signed-off-by:
Israel Rukshin <israelr@mellanox.com> Reviewed-by:
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Israel Rukshin authored
Since commit b86dd815 "block: get rid of blk-mq default scheduler choice Kconfig entries", when setting nr_hw_queues to 1 the admin tag set uses mq-deadline scheduler. This flag is useful for admin queues that aren't used for normal IO. Signed-off-by:
James Smart <james.smart@broadcom.com> Signed-off-by:
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Israel Rukshin authored
Since commit b86dd815 "block: get rid of blk-mq default scheduler choice Kconfig entries", when setting nr_hw_queues to 1 the admin tag set uses mq-deadline scheduler. This flag is useful for admin queues that aren't used for normal IO. Signed-off-by:
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Minwoo Im authored
fixed comment typos in adapter_alloc_cq() and adapter_alloc_sq(). 'the the' duplications are replaced with 'that the'. Signed-off-by:
Minwoo Im <dn3108@gmail.com> Signed-off-by:
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- 18 Oct, 2017 11 commits
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Sagi Grimberg authored
If the controller is deleting (in case the user decided to delete it), we have no point to continue reset sequence. Signed-off-by:
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Sagi Grimberg authored
Instead of marking we are deleting, mark we are allocated and check that instead. This makes the logic symmetrical to connected mark check. Signed-off-by:
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Sagi Grimberg authored
No chance for the local invalidate to succeed if the queue-pair is in error state. Most likely the target will do a remote invalidation of our mr so not a big loss on the test_bit. Signed-off-by:
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Sagi Grimberg authored
Relying on the queue state while tearing down on every reconnect attempt is not a good design. We should do it once in err_work and simply try to establish the queues for each reconnect attempt. Signed-off-by:
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Sagi Grimberg authored
Warn if req->mr is NULL as it should never happen. Reviewed-by:
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Sagi Grimberg authored
No need for the extra line for trivial assignments. Signed-off-by:
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Sagi Grimberg authored
Not necessarily address resolution failed. Signed-off-by:
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Sagi Grimberg authored
Instead of flagging admin/io. Signed-off-by:
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Sagi Grimberg authored
No callers left. Reviewed-by:
Jens Axboe <axboe@kernel.dk> Reviewed-by:
Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by:
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Sagi Grimberg authored
Move blk_mq_reinit_tagset from blk-mq to nvme core as the only user of it. Current transports that use it (rdma, fc) simply implement .reinit_request op. This patch does not change any functionality. Reviewed-by:
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Sagi Grimberg authored
Iterator helper to apply a function on all the tags in a given tagset. export it as it will be used outside the block layer later on. Reviewed-by:
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- 16 Oct, 2017 1 commit
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Christoph Hellwig authored
We can just use our normal ioctl handler for the compat case and remove the boilerplate code for it. Signed-off-by:
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- 05 Oct, 2017 1 commit
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James Smart authored
move nvme_fc_rport_get/put and rport free to higher in the file to avoid adding prototypes to resolve references in upcoming code additions Signed-off-by:
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- 04 Oct, 2017 6 commits
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James Smart authored
Added a new fc class and a device node for udev events under it. I expect the fc class will eventually be the location where the FC SCSI and FC NVME merge in the future. Therefore names are kept somewhat generic. Signed-off-by:
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James Smart authored
To support auto-connecting to FC-NVME devices upon their dynamic appearance, add a uevent that can kick off connection scripts. uevent is posted against the fc_udev device. patch set tested with the following rule to kick an nvme-cli connect-all for the FC initiator and FC target ports. This is just an example for testing and not intended for real life use. ACTION=="change", SUBSYSTEM=="fc", ENV{FC_EVENT}=="nvmediscovery", \ ENV{NVMEFC_HOST_TRADDR}=="*", ENV{NVMEFC_TRADDR}=="*", \ RUN+="/bin/sh -c '/usr/local/sbin/nvme connect-all --transport=fc --host-traddr=$env{NVMEFC_HOST_TRADDR} --traddr=$env{NVMEFC_TRADDR} >> /tmp/nvme_fc.log'" I will post proposed udev/systemd scripts for possible kernel support. Signed-off-by: -
Sagi Grimberg authored
Help userspace to make sure transport module is loaded. Signed-off-by:
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James Smart authored
Raise the max number of IO queues to 128. There are several hosts with more than 64 cpus/threads. Signed-off-by:
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Randy Dunlap authored
Add a menu interface for NVME host and target support so that it is presented to users more like other Kconfig symbols. This makes the Device Driver menu less cluttered (easier to read) and keeps all of these symbols grouped together. Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Reviewed-by:
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Marc Olson authored
The underlying blk_mq_tag_set, and request timeout parameters support an unsigned int. Extend the size of the nvme module parameters for io and admin commands to match. Signed-off-by:
Marc Olson <marcolso@amazon.com> Signed-off-by:
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- 03 Oct, 2017 14 commits
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Christoph Hellwig authored
No need to have this helper inline in a header. Also drop the __ prefix. Signed-off-by:
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Paolo Valente authored
If many queues belonging to the same group happen to be created shortly after each other, then the concurrent processes associated with these queues have typically a common goal, and they get it done as soon as possible if not hampered by device idling. Examples are processes spawned by git grep, or by systemd during boot. As for device idling, this mechanism is currently necessary for weight raising to succeed in its goal: privileging I/O. In view of these facts, BFQ does not provide the above queues with either weight raising or device idling. On the other hand, a burst of queue creations may be caused also by the start-up of a complex application. In this case, these queues need usually to be served one after the other, and as quickly as possible, to maximise responsiveness. Therefore, in this case the best strategy is to weight-raise all the queues created during the burst, i.e., the exact opposite of the strategy for the above case. To distinguish between the two cases, BFQ uses an empirical burst-size threshold, found through extensive tests and monitoring of daily usage. Only large bursts, i.e., burst with a size above this threshold, are considered as generated by a high number of parallel processes. In this respect, upstart-based boot proved to be rather hard to detect as generating a large burst of queue creations, because with upstart most of the queues created in a burst exit *before* the next queues in the same burst are created. To address this issue, I changed the burst-detection mechanism so as to not decrease the size of the current burst even if one of the queues in the burst is eliminated. Unfortunately, this missing decrease causes false positives on very fast systems: on the start-up of a complex application, such as libreoffice writer, so many queues are created, served and exited shortly after each other, that a large burst of queue creations is wrongly detected as occurring. These false positives just disappear if the size of a burst is decreased when one of the queues in the burst exits. This commit restores the missing burst-size decrease, relying of the fact that upstart is apparently unlikely to be used on systems running this and future versions of the kernel. Signed-off-by:
Paolo Valente <paolo.valente@linaro.org> Signed-off-by:
Mauro Andreolini <mauro.andreolini@unimore.it> Signed-off-by:
Angelo Ruocco <angeloruocco90@gmail.com> Tested-by:
Mirko Montanari <mirkomontanari91@gmail.com> Tested-by:
Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by:
Lee Tibbert <lee.tibbert@gmail.com> Signed-off-by:
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Paolo Valente authored
A just-created bfq_queue, say Q, may happen to be merged with another bfq_queue on the very first invocation of the function __bfq_insert_request. In such a case, even if Q would clearly deserve interactive weight raising (as it has just been created), the function bfq_add_request does not make it to be invoked for Q, and thus to activate weight raising for Q. As a consequence, when the state of Q is saved for a possible future restore, after a split of Q from the other bfq_queue(s), such a state happens to be (unjustly) non-weight-raised. Then the bfq_queue will not enjoy any weight raising on the split, even if should still be in an interactive weight-raising period when the split occurs. This commit solves this problem as follows, for a just-created bfq_queue that is being early-merged: it stores directly, in the saved state of the bfq_queue, the weight-raising state that would have been assigned to the bfq_queue if not early-merged. Signed-off-by:
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Paolo Valente authored
As already explained in the message of commit "block, bfq: fix wrong init of saved start time for weight raising", if a soft real-time weight-raising period happens to be nested in a larger interactive weight-raising period, then BFQ restores the interactive weight raising at the end of the soft real-time weight raising. In particular, BFQ checks whether the latter has ended only on request dispatches. Unfortunately, the above scheme fails to restore interactive weight raising in the following corner case: if a bfq_queue, say Q, 1) Is merged with another bfq_queue while it is in a nested soft real-time weight-raising period. The weight-raising state of Q is then saved, and not considered any longer until a split occurs. 2) Is split from the other bfq_queue(s) at a time instant when its soft real-time weight raising is already finished. On the split, while resuming the previous, soft real-time weight-raised state of the bfq_queue Q, BFQ checks whether the current soft real-time weight-raising period is actually over. If so, BFQ switches weight raising off for Q, *without* checking whether the soft real-time period was actually nested in a non-yet-finished interactive weight-raising period. This commit addresses this issue by adding the above missing check in bfq_queue splits, and restoring interactive weight raising if needed. Signed-off-by:
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Paolo Valente authored
This commit fixes a bug that causes bfq to fail to guarantee a high responsiveness on some drives, if there is heavy random read+write I/O in the background. More precisely, such a failure allowed this bug to be found [1], but the bug may well cause other yet unreported anomalies. BFQ raises the weight of the bfq_queues associated with soft real-time applications, to privilege the I/O, and thus reduce latency, for these applications. This mechanism is named soft-real-time weight raising in BFQ. A soft real-time period may happen to be nested into an interactive weight raising period, i.e., it may happen that, when a bfq_queue switches to a soft real-time weight-raised state, the bfq_queue is already being weight-raised because deemed interactive too. In this case, BFQ saves in a special variable wr_start_at_switch_to_srt, the time instant when the interactive weight-raising period started for the bfq_queue, i.e., the time instant when BFQ started to deem the bfq_queue interactive. This value is then used to check whether the interactive weight-raising period would still be in progress when the soft real-time weight-raising period ends. If so, interactive weight raising is restored for the bfq_queue. This restore is useful, in particular, because it prevents bfq_queues from losing their interactive weight raising prematurely, as a consequence of spurious, short-lived soft real-time weight-raising periods caused by wrong detections as soft real-time. If, instead, a bfq_queue switches to soft-real-time weight raising while it *is not* already in an interactive weight-raising period, then the variable wr_start_at_switch_to_srt has no meaning during the following soft real-time weight-raising period. Unfortunately the handling of this case is wrong in BFQ: not only the variable is not flagged somehow as meaningless, but it is also set to the time when the switch to soft real-time weight-raising occurs. This may cause an interactive weight-raising period to be considered mistakenly as still in progress, and thus a spurious interactive weight-raising period to start for the bfq_queue, at the end of the soft-real-time weight-raising period. In particular the spurious interactive weight-raising period will be considered as still in progress, if the soft-real-time weight-raising period does not last very long. The bfq_queue will then be wrongly privileged and, if I/O bound, will unjustly steal bandwidth to truly interactive or soft real-time bfq_queues, harming responsiveness and low latency. This commit fixes this issue by just setting wr_start_at_switch_to_srt to minus infinity (farthest past time instant according to jiffies macros): when the soft-real-time weight-raising period ends, certainly no interactive weight-raising period will be considered as still in progress. [1] Background I/O Type: Random - Background I/O mix: Reads and writes - Application to start: LibreOffice Writer in http://www.phoronix.com/scan.php?page=news_item&px=Linux-4.13-IO-LaptopSigned-off-by:
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Jens Axboe authored
When someone calls wakeup_flusher_threads() or wakeup_flusher_threads_bdi(), they schedule writeback of all dirty pages in the system (or on that bdi). If we are tight on memory, we can get tons of these queued from kswapd/vmscan. This causes (at least) two problems: 1) We consume a ton of memory just allocating writeback work items. We've seen as much as 600 million of these writeback work items pending. That's a lot of memory to pointlessly hold hostage, while the box is under memory pressure. 2) We spend so much time processing these work items, that we introduce a softlockup in writeback processing. This is because each of the writeback work items don't end up doing any work (it's hard when you have millions of identical ones coming in to the flush machinery), so we just sit in a tight loop pulling work items and deleting/freeing them. Fix this by adding a 'start_all' bit to the writeback structure, and set that when someone attempts to flush all dirty pages. The bit is cleared when we start writeback on that work item. If the bit is already set when we attempt to queue !nr_pages writeback, then we simply ignore it. This provides us one full flush in flight, with one pending as well, and makes for more efficient handling of this type of writeback. Acked-by:
Johannes Weiner <hannes@cmpxchg.org> Tested-by:
Chris Mason <clm@fb.com> Reviewed-by:
Jan Kara <jack@suse.cz> Signed-off-by:
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Jens Axboe authored
Now that we have no external callers of wb_start_writeback(), we can shuffle the passing in of 'nr_pages'. Everybody passes in 0 at this point, so just kill the argument and move the dirty count retrieval to that function. Acked-by:
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Jens Axboe authored
We don't have any callers outside of fs-writeback.c anymore, make it private. Acked-by:
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Jens Axboe authored
Laptop mode really wants to writeback the number of dirty pages and inodes. Instead of calculating this in the caller, just pass in 0 and let wakeup_flusher_threads() handle it. Use the new wakeup_flusher_threads_bdi() instead of rolling our own. Acked-by:
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Jens Axboe authored
Similar to wakeup_flusher_threads(), except that we only wake up the flusher threads on the specified backing device. No functional changes in this patch. Acked-by:
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Jens Axboe authored
All the callers pass in 'true' for range_cyclic, so kill the argument. Signed-off-by: -
Jens Axboe authored
We're writing back the full range of dirty pages on the devices, there's no point in making this special and not do normal range cyclic writeback. Reviewed-by:
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Jens Axboe authored
Everybody is passing in 0 now, let's get rid of the argument. Reviewed-by:
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Jens Axboe authored
Since the previous commit removed any case where grow_buffers() would return failure due to memory allocations, we can safely remove the case where we have to call free_more_memory() in this function. Since this is also the last user of free_more_memory(), kill it off completely. Reviewed-by:
Nikolay Borisov <nborisov@suse.com> Reviewed-by:
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