kernel/linux.git/drivers/vhost/vhost.c, branch v3.0.95

vhost: fix length for cross region descriptor

2013-03-03T22:09:05+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

vhost: don't forget to schedule()

2012-07-16T15:47:51+00:00

commit d550dda192c1bd039afb774b99485e88b70d7cb8 upstream. 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 Cc: Jean Delvare Signed-off-by: Greg Kroah-Hartman

vhost: support event index

2011-05-30T01:44:15+00:00

Support the new event index feature. When acked, utilize it to reduce the # of interrupts sent to the guest. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell

Correct occurrences of

2011-05-06T16:27:55+00:00

- Documentation/kvm/ to Documentation/virtual/kvm - Documentation/uml/ to Documentation/virtual/uml - Documentation/lguest/ to Documentation/virtual/lguest throughout the kernel source tree. Signed-off-by: Rob Landley Signed-off-by: Randy Dunlap

vhost: copy_from_user -> __copy_from_user

2011-03-08T16:03:05+00:00

copy_from_user is pretty high on perf top profile, replacing it with __copy_from_user helps. It's also safe because we do access_ok checks during setup. Signed-off-by: Michael S. Tsirkin

vhost: Cleanup vhost.c and net.c

2011-03-08T16:02:47+00:00

Minor cleanup of vhost.c and net.c to match coding style. Signed-off-by: Krishna Kumar Signed-off-by: Michael S. Tsirkin

vhost: fix signed/unsigned comparison

2011-01-10T08:03:39+00:00

To detect that a sequence number is done, we are doing math on unsigned integers so the result is unsigned too. Not what was intended for the <= comparison. The result is user stuck forever in flush call. Convert to int to fix this. Further, get rid of ({}) to make code clearer. Signed-off-by: Michael S. Tsirkin

vhost: better variable name in logging

2010-12-09T14:00:10+00:00

We really store a page offset in write_address, so rename it write_page to avoid confusion. Signed-off-by: Jason Wang Signed-off-by: Michael S. Tsirkin

vhost: correctly set bits of dirty pages

2010-12-09T13:39:17+00:00

Fix two bugs in dirty page logging: When counting pages we should increase address by 1 instead of VHOST_PAGE_SIZE. Make log_write() correctly process requests that cross pages with write_address not starting at page boundary. Reported-by: Jason Wang Signed-off-by: Michael S. Tsirkin

vhost: remove unused include

2010-12-09T13:39:13+00:00

vhost.c does not need to know about sockets, don't include sock.h Signed-off-by: Michael S. Tsirkin