diff options
| author | Bob Liu <bob.liu@oracle.com> | 2015-11-14 11:12:17 +0800 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2016-01-04 12:21:06 -0500 |
| commit | d62d86000316d7ef38e1c2e9602c3ce6d1cb57bd (patch) | |
| tree | aa9fa8a5fce0608532787214b8f40a5075871a6d /drivers/block/xen-blkback/blkback.c | |
| parent | 2fb1ef4f1226ea6d6d3481036cabe01a4415b68c (diff) | |
xen/blkback: get the number of hardware queues/rings from blkfront
Backend advertises "multi-queue-max-queues" to front, also get the negotiated
number from "multi-queue-num-queues" written by blkfront.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'drivers/block/xen-blkback/blkback.c')
| -rw-r--r-- | drivers/block/xen-blkback/blkback.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 4fd8640d146c..18b27770d80b 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -84,6 +84,16 @@ MODULE_PARM_DESC(max_persistent_grants, "Maximum number of grants to map persistently"); /* + * Maximum number of rings/queues blkback supports, allow as many queues as there + * are CPUs if user has not specified a value. + */ +unsigned int xenblk_max_queues; +module_param_named(max_queues, xenblk_max_queues, uint, 0644); +MODULE_PARM_DESC(max_queues, + "Maximum number of hardware queues per virtual disk." \ + "By default it is the number of online CPUs."); + +/* * Maximum order of pages to be used for the shared ring between front and * backend, 4KB page granularity is used. */ @@ -1483,6 +1493,9 @@ static int __init xen_blkif_init(void) xen_blkif_max_ring_order = XENBUS_MAX_RING_GRANT_ORDER; } + if (xenblk_max_queues == 0) + xenblk_max_queues = num_online_cpus(); + rc = xen_blkif_interface_init(); if (rc) goto failed_init; |