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| author |   Hannes Reinecke <hare@suse.de> | 2019-02-18 11:43:26 +0100 |
|---|---|---|
| committer |   Christoph Hellwig <hch@lst.de> | 2019-02-20 07:17:49 -0700 |
| commit | 75c10e73272484bc3a940a9c8e4ec39a7a1b8c21 (patch) | |
| tree | c0c20ba4d5600d531bf0ed2c362888fa963097a6 /drivers/nvme/host/nvme.h | |
| parent | block: avoid to READ fields of null bio (diff) | |
| download | linux-dev-75c10e73272484bc3a940a9c8e4ec39a7a1b8c21.tar.xz linux-dev-75c10e73272484bc3a940a9c8e4ec39a7a1b8c21.zip | |
nvme-multipath: round-robin I/O policy
Implement a simple round-robin I/O policy for multipathing. Path
selection is done in two rounds, first iterating across all optimized
paths, and if that doesn't return any valid paths, iterate over all
optimized and non-optimized paths. If no paths are found, use the
existing algorithm. Also add a sysfs attribute 'iopolicy' to switch
between the current NUMA-aware I/O policy and the 'round-robin' I/O
policy.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to '')
| -rw-r--r-- | drivers/nvme/host/nvme.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index 23db2d99b53a..8c646ab26677 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -252,6 +252,11 @@ struct nvme_ctrl { unsigned long discard_page_busy; }; +enum nvme_iopolicy { + NVME_IOPOLICY_NUMA, + NVME_IOPOLICY_RR, +}; + struct nvme_subsystem { int instance; struct device dev; @@ -271,6 +276,9 @@ struct nvme_subsystem { u8 cmic; u16 vendor_id; struct ida ns_ida; +#ifdef CONFIG_NVME_MULTIPATH + enum nvme_iopolicy iopolicy; +#endif }; /* @@ -491,6 +499,7 @@ static inline void nvme_mpath_check_last_path(struct nvme_ns *ns) extern struct device_attribute dev_attr_ana_grpid; extern struct device_attribute dev_attr_ana_state; +extern struct device_attribute subsys_attr_iopolicy; #else static inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl) |