linux-stable.git/drivers/vhost/vhost.c, branch linux-3.4.y

vhost: actually track log eventfd file

2016-03-21T01:17:49+00:00

commit 7932c0bd7740f4cd2aa168d3ce0199e7af7d72d5 upstream.

While reviewing vhost log code, I found out that log_file is never
set. Note: I haven't tested the change (QEMU doesn't use LOG_FD yet).

Signed-off-by: Marc-André Lureau 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Zefan Li

vhost: zerocopy: poll vq in zerocopy callback

2013-09-14T13:02:10+00:00

commit c70aa540c7a9f67add11ad3161096fb95233aa2e upstream.

We add used and signal guest in worker thread but did not poll the virtqueue
during the zero copy callback. This may lead the missing of adding and
signalling during zerocopy. Solve this by polling the virtqueue and let it
wakeup the worker during callback.

Signed-off-by: Jason Wang 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Greg Kroah-Hartman

vhost: fix length for cross region descriptor

2013-03-03T22:06:43+00:00

commit bd97120fc3d1a11f3124c7c9ba1d91f51829eb85 upstream.

If a single descriptor crosses a region, the
second chunk length should be decremented
by size translated so far, instead it includes
the full descriptor length.

Signed-off-by: Michael S. Tsirkin 
Acked-by: Jason Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

skbuff: struct ubuf_info callback type safety

2012-04-13T17:09:19+00:00

The skb struct ubuf_info callback gets passed struct ubuf_info
itself, not the arg value as the field name and the function signature
seem to imply. Rename the arg field to ctx to match usage,
add documentation and change the callback argument type
to make usage clear and to have compiler check correctness.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller

Merge branch 'vhost-net' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2012-03-23T18:46:48+00:00

vhost: remove the second argument of k[un]map_atomic()

2012-03-20T13:48:21+00:00

Signed-off-by: Cong Wang

vhost: fix release path lockdep checks

2012-02-28T07:13:22+00:00

We shouldn't hold any locks on release path. Pass a flag to
vhost_dev_cleanup to use the lockdep info correctly.

Signed-off-by: Michael S. Tsirkin 
Tested-by: Sasha Levin

vhost: don't forget to schedule()

2012-02-28T07:13:19+00:00

This is a tiny, but important, patch to vhost.

Vhost's worker thread only called schedule() when it had no work to do, and
it wanted to go to sleep. But if there's always work to do, e.g., the guest
is running a network-intensive program like netperf with small message sizes,
schedule() was *never* called. This had several negative implications (on
non-preemptive kernels):

 1. Passing time was not properly accounted to the "vhost" process (ps and
    top would wrongly show it using zero CPU time).

 2. Sometimes error messages about RCU timeouts would be printed, if the
    core running the vhost thread didn't schedule() for a very long time.

 3. Worst of all, a vhost thread would "hog" the core. If several vhost
    threads need to share the same core, typically one would get most of the
    CPU time (and its associated guest most of the performance), while the
    others hardly get any work done.

The trivial solution is to add

	if (need_resched())
		schedule();

After doing every piece of work. This will not do the heavy schedule() all
the time, just when the timer interrupt decided a reschedule is warranted
(so need_resched returns true).

Thanks to Abel Gordon for this patch.

Signed-off-by: Nadav Har'El 
Signed-off-by: Michael S. Tsirkin

vhost: optimize interrupt enable/disable

2011-07-19T14:17:28+00:00

As we now only update used ring after enabling
the backend, we can write flags with __put_user:
as that's done on data path, it matters.

Signed-off-by: Michael S. Tsirkin

vhost: fix zcopy reference counting

2011-07-19T10:28:34+00:00

Fix get/put refcount imbalance with zero copy,
which caused qemu to hang forever on guest driver unload.

Signed-off-by: Michael S. Tsirkin