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>
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File | Mode | Size |
---|---|---|
Kconfig | -rw-r--r-- | 1.4 KB |
Makefile | -rw-r--r-- | 160 bytes |
checkpoint.c | -rw-r--r-- | 19.5 KB |
commit.c | -rw-r--r-- | 33.7 KB |
journal.c | -rw-r--r-- | 75.6 KB |
recovery.c | -rw-r--r-- | 21.4 KB |
revoke.c | -rw-r--r-- | 21.2 KB |
transaction.c | -rw-r--r-- | 82.2 KB |
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