- 08 Apr, 2013 6 commits
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Wanlong Gao authored
Add hot cpu notifier to reset the request virtqueue affinity when doing cpu hotplug. Cc: linux-scsi@vger.kernel.org Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
Wanlong Gao <gaowanlong@cn.fujitsu.com> Reviewed-by:
Asias He <asias@redhat.com> Signed-off-by:
Rusty Russell <rusty@rustcorp.com.au>
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Paolo Bonzini authored
This patch adds queue steering to virtio-scsi. When a target is sent multiple requests, we always drive them to the same queue so that FIFO processing order is kept. However, if a target was idle, we can choose a queue arbitrarily. In this case the queue is chosen according to the current VCPU, so the driver expects the number of request queues to be equal to the number of VCPUs. This makes it easy and fast to select the queue, and also lets the driver optimize the IRQ affinity for the virtqueues (each virtqueue's affinity is set to the CPU that "owns" the queue). The speedup comes from improving cache locality and giving CPU affinity to the virtqueues, which is why this scheme was selected. Assuming that the thread that is sending requests to the device is I/O-bound, it is likely to be sleeping at the time the ISR is executed, and thus executing the ISR on the same processor that sent the requests is cheap. However, the kernel will not execute the ISR on the "best" processor unless you explicitly set the affinity. This is because in practice you will have many such I/O-bound processes and thus many otherwise idle processors. Then the kernel will execute the ISR on a random processor, rather than the one that is sending requests to the device. The alternative to per-CPU virtqueues is per-target virtqueues. To achieve the same locality, we could dynamically choose the virtqueue's affinity based on the CPU of the last task that sent a request. This is less appealing because we do not set the affinity directly---we only provide a hint to the irqbalanced running in userspace. Dynamically changing the affinity only works if the userspace applies the hint fast enough. Cc: linux-scsi@vger.kernel.org Signed-off-by:
Venkatesh Srinivas <venkateshs@google.com> Signed-off-by:
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Paolo Bonzini authored
Avoid duplicated code in all of the callers. Cc: linux-scsi@vger.kernel.org Signed-off-by:
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Paolo Bonzini authored
This will be needed soon in order to retrieve the per-target struct. Cc: linux-scsi@vger.kernel.org Signed-off-by:
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Wanlong Gao authored
virtio_scsi_target_state is now empty. We will find new uses for it in the next few patches, so this patch does not drop it completely. And as James suggested, we use entries target_alloc and target_destroy in the host template to allocate and destroy the virtio_scsi_target_state of each target, attach this struct to scsi_target->hostdata. Now we can get at it from the sdev with scsi_target(sdev)->hostdata. No messing around with fixed size arrays and bulk memory allocation and no need to pass in the maximum target size as a parameter because everything should now happen dynamically. Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: linux-scsi@vger.kernel.org Signed-off-by:
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Wei Yongjun authored
Those symbols only used within this file, and should be static. Signed-off-by:
Wei Yongjun <yongjun_wei@trendmicro.com.cn> Acked-by:
Amit Shah <amit.shah@redhat.com> Signed-off-by:
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- 02 Apr, 2013 3 commits
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Wei Yongjun authored
Fix to return a negative error code from the error handling case instead of 0, as returned elsewhere in this function. Signed-off-by:
Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by:
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Amos Kong authored
Some head files were split or moved to uapi/ without updating MAINTAINERS. Signed-off-by:
Amos Kong <kongjianjun@gmail.com> Signed-off-by:
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Paul Bolle authored
virtio_balloon.h exports "u16" and "u64" to userspace. Use "__u16" and "__u64" instead. Signed-off-by:
Paul Bolle <pebolle@tiscali.nl> Signed-off-by:
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- 24 Mar, 2013 2 commits
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Sjur Brændeland authored
Check that vringh_config is not NULL before using it. Signed-off-by:
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Sjur Brændeland authored
Check on the correct return value from vringh_notify_enable_kern(). It returns false if more packets are available, not true. Signed-off-by:
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- 20 Mar, 2013 26 commits
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Rusty Russell authored
Make the rest of the paths use virtqueue_add_sgs or add_outbuf. Signed-off-by: -
Rusty Russell authored
virtio_add_buf() is going away, replaced with virtio_add_sgs() which takes multiple terminated scatterlists. Cc: Eric Van Hensbergen <ericvh@gmail.com> Signed-off-by: -
Rusty Russell authored
We never add buffers with input and output parts, so use the new accessors. Signed-off-by: -
Rusty Russell authored
We never add buffers with input and output parts, so use the new accessors. Cc: Ohad Ben-Cohen <ohad@wizery.com> Signed-off-by: -
Rusty Russell authored
We never add buffers with input and output parts, so use the new accessors. Cc: Sjur Brendeland <sjur.brandeland@stericsson.com> Signed-off-by: -
Rusty Russell authored
We never add buffers with input and output parts, so use the new accessors. Acked-by:
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Rusty Russell authored
We never add buffers with input and output parts, so use the new accessors. Signed-off-by:
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Rusty Russell authored
We never add buffers with input and output parts, so use the new accessors. Cc: "Michael S. Tsirkin" <mst@redhat.com> Reviewed-by:
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Rusty Russell authored
It's a bit cleaner to hand multiple sgs, rather than one big one. Cc: "Michael S. Tsirkin" <mst@redhat.com> Tested-by:
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Rusty Russell authored
It's a bit clearer, and add_buf is going away. Signed-off-by:
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Wanlong Gao authored
Using the new virtqueue_add_sgs function lets us simplify the queueing path. In particular, all data protected by the tgt_lock is just gone (multiqueue will find a new use for the lock). Signed-off-by:
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Rusty Russell authored
It's simply a flag as to whether we have data now, so make it an explicit function parameter rather than a member of struct virtblk_req. Signed-off-by:
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Paolo Bonzini authored
(This is a respin of Paolo Bonzini's patch, but it calls virtqueue_add_sgs() instead of his multi-part API). This is similar to the previous patch, but a bit more radical because the bio and req paths now share the buffer construction code. Because the req path doesn't use vbr->sg, however, we need to add a couple of arguments to __virtblk_add_req. We also need to teach __virtblk_add_req how to build SCSI command requests. Signed-off-by:
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Paolo Bonzini authored
(This is a respin of Paolo Bonzini's patch, but it calls virtqueue_add_sgs() instead of his multi-part API). Move the creation of the request header and response footer to __virtblk_add_req. vbr->sg only contains the data scatterlist, the header/footer are added separately using virtqueue_add_sgs(). With this change, virtio-blk (with use_bio) is not relying anymore on the virtio functions ignoring the end markers in a scatterlist. The next patch will do the same for the other path. Signed-off-by:
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Paolo Bonzini authored
Right now, both virtblk_add_req and virtblk_add_req_wait call virtqueue_add_buf. To prepare for the next patches, abstract the call to virtqueue_add_buf into a new function __virtblk_add_req, and include the waiting logic directly in virtblk_add_req. Signed-off-by:
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Rusty Russell authored
As expected, the simplified accessors are faster. for i in `seq 50`; do /usr/bin/time -f 'Wall time:%e' ./vringh_test --indirect --eventidx --parallel --fast-vringh; done 2>&1 | stats --trim-outliers: Before: Using CPUS 0 and 3 Guest: notified 0, pinged 39062-39063(39063) Host: notified 39062-39063(39063), pinged 0 Wall time:1.760000-2.220000(1.789167) After: Using CPUS 0 and 3 Guest: notified 0, pinged 39037-39063(39062) Host: notified 39037-39063(39062), pinged 0 Wall time:1.640000-1.810000(1.676875) Signed-off-by: -
Rusty Russell authored
These are specialized versions of virtqueue_add_buf(), which cover over 80% of cases and are far clearer. In particular, the scatterlists passed to these functions don't have to be clean (ie. we ignore end markers). Signed-off-by: -
Rusty Russell authored
virtio_scsi can really use this, to avoid the current hack of copying the whole sg array. Some other things get slightly neater, too. This causes a slowdown in virtqueue_add_buf(), which is implemented as a wrapper. This is addressed in the next patches. for i in `seq 50`; do /usr/bin/time -f 'Wall time:%e' ./vringh_test --indirect --eventidx --parallel --fast-vringh; done 2>&1 | stats --trim-outliers: Before: Using CPUS 0 and 3 Guest: notified 0, pinged 39009-39063(39062) Host: notified 39009-39063(39062), pinged 0 Wall time:1.700000-1.950000(1.723542) After: Using CPUS 0 and 3 Guest: notified 0, pinged 39062-39063(39063) Host: notified 39062-39063(39063), pinged 0 Wall time:1.760000-2.220000(1.789167) Signed-off-by:
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Paolo Bonzini authored
This is useful in places that recycle the same scatterlist multiple times, and do not want to incur the cost of sg_init_table every time in hot paths. Acked-by:
Jens Axboe <axboe@kernel.dk> Signed-off-by:
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Erwan Yvin authored
Add the CAIF Virtio shared memory driver for talking to a modem. This CAIF Link layer communicates to the modem over shared memory. It is implemented as a virtio_driver. The underlying virtio device is managed by the remoteproc framework. The Virtio queue is used for transmitting data to the modem, and the new vringh is used for receiving data. Genalloc is used for managing the shared memory used for TX data. The default dma-alloc-coherent allocator can only allocate whole pages, and this wastes too much shared memory. Flow control is implemented by stopping the TX-queues if the virtio queues go full or we run out of memory. Queued are reopened when queues are below the watermark. NAPI is used in RX path, and a dedicated tasklet is used for releasing TX buffers. Signed-off-by:
Erwan Yvin <erwan.yvin@stericsson.com> Acked-by:
David S. Miller <davem@davemloft.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (minor fixes)
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Sjur Brændeland authored
Add wrappers for the host vrings to support loose coupling between the virtio device and driver. A new struct vringh_config_ops with the functions find_vrhs() and del_vrhs() is added to the virtio_device struct. This enables virtio drivers to manage virtio host rings without detailed knowledge of how the vrings are created and deleted. The function vringh_notify() is added so vringh clients can notify the other side that buffers are added to the used-ring. Cc: Ohad Ben-Cohen <ohad@wizery.com> Signed-off-by: -
Rusty Russell authored
This is mainly to test the drivers/vhost/vringh.c code, but it also uses the drivers/virtio/virtio_ring.c code for the guest side. Usage for testing the basic implementation: ./vringh_test # Test with indirect descriptors ./vringh_test --indirect # Test with indirect descriptors and event indexex ./vringh_test --indirect --eventidx You can run a parallel stress test by adding --parallel to any of the above options. eg ./vringh_test --parallel: Using CPUS 0 and 3 Guest: notified 10107974, pinged 107970 Host: notified 108158, pinged 3172148 ./vringh_test --indirect --eventidx --parallel: Using CPUS 0 and 3 Guest: notified 156357, pinged 156251 Host: notified 156251, pinged 78179 Average of 50 times doing ./vringh_test --indirect --eventidx --parallel: 2.840000-3.040000(2.927292)user Signed-off-by: -
Rusty Russell authored
Getting use of virtio rings correct is tricky, and a recent patch saw an implementation of in-kernel rings (as separate from userspace). This abstracts the business of dealing with the virtio ring layout from the access (userspace or direct); to do this, we use function pointers, which gcc inlines correctly. Signed-off-by:
Michael S. Tsirkin <mst@redhat.com>
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Rusty Russell authored
This makes them a bit more like the kernel headers, so we can include more real kernel headers in our tests. In addition this means that we don't break tools/virtio with the next patch. Signed-off-by: -
Rusty Russell authored
The host side of ring needs this logic too. Signed-off-by: -
Michael S. Tsirkin authored
Signed-off-by:
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- 12 Mar, 2013 3 commits
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Rusty Russell authored
We haven't been keeping it in sync, so just remove it. Signed-off-by: -
Milos Vyletel authored
When virtio-blk device is resized from host (using block_resize from QEMU) emit KOBJ_CHANGE uevent to notify guest about such change. This allows user to have custom udev rules which would take whatever action if such event occurs. As a proof of concept I've created simple udev rule that automatically resize filesystem on virtio-blk device. ACTION=="change", KERNEL=="vd*", \ ENV{RESIZE}=="1", \ ENV{ID_FS_TYPE}=="ext[3-4]", \ RUN+="/sbin/resize2fs /dev/%k" ACTION=="change", KERNEL=="vd*", \ ENV{RESIZE}=="1", \ ENV{ID_FS_TYPE}=="LVM2_member", \ RUN+="/sbin/pvresize /dev/%k" Signed-off-by:Milos Vyletel <milos.vyletel@sde.cz> Tested-by:
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Wanlong Gao authored
Convert the virtio-scsi driver to use pr_err() instead of printk(). Signed-off-by:
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