Revision 1978f30a87732d4d9072a20abeded9fe17884f1b authored by Dongli Zhang on 27 March 2019, 10:36:35 UTC, committed by Jens Axboe on 10 April 2019, 14:18:25 UTC
When tag_set->nr_maps is 1, the block layer limits the number of hw queues by nr_cpu_ids. No matter how many hw queues are used by virtio-scsi, as it has (tag_set->nr_maps == 1), it can use at most nr_cpu_ids hw queues. In addition, specifically for pci scenario, when the 'num_queues' specified by qemu is more than maxcpus, virtio-scsi would not be able to allocate more than maxcpus vectors in order to have a vector for each queue. As a result, it falls back into MSI-X with one vector for config and one shared for queues. Considering above reasons, this patch limits the number of hw queues used by virtio-scsi by nr_cpu_ids. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
1 parent bf348f9
| File | Mode | Size |
|---|---|---|
| Makefile | -rw-r--r-- | 381 bytes |
| clnt4xdr.c | -rw-r--r-- | 12.9 KB |
| clntlock.c | -rw-r--r-- | 7.4 KB |
| clntproc.c | -rw-r--r-- | 21.7 KB |
| clntxdr.c | -rw-r--r-- | 13.2 KB |
| host.c | -rw-r--r-- | 17.2 KB |
| mon.c | -rw-r--r-- | 14.3 KB |
| netns.h | -rw-r--r-- | 395 bytes |
| procfs.c | -rw-r--r-- | 1.8 KB |
| procfs.h | -rw-r--r-- | 474 bytes |
| svc.c | -rw-r--r-- | 19.1 KB |
| svc4proc.c | -rw-r--r-- | 14.1 KB |
| svclock.c | -rw-r--r-- | 25.1 KB |
| svcproc.c | -rw-r--r-- | 14.9 KB |
| svcshare.c | -rw-r--r-- | 2.4 KB |
| svcsubs.c | -rw-r--r-- | 10.3 KB |
| xdr.c | -rw-r--r-- | 7.3 KB |
| xdr4.c | -rw-r--r-- | 7.6 KB |
Computing file changes ...
