Commit Graph

4 Commits

Author SHA1 Message Date
Marcelo Tosatti dcc38d1cce signalfd compatibility
Port qemu-kvm's signalfd compat code.

commit 5a7fdd0abd7cd24dac205317a4195446ab8748b5
Author: Anthony Liguori <aliguori@us.ibm.com>
Date:   Wed May 7 11:55:47 2008 -0500

    Use signalfd() in io-thread

    This patch reworks the IO thread to use signalfd() instead of sigtimedwait()
    This will eliminate the need to use SIGIO everywhere.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-20 16:15:04 -05:00
aliguori 9e472e101f Fix IO performance regression in sparc
Replace signalfd with signal handler/pipe.  There is no way to interrupt
the CPU execution loop when a file descriptor becomes readable.  This
results in a large performance regression in sparc emulation during
bootup.
   
This patch switches us to signal handler/pipe which was originally
suggested by Ian Jackson.  The signal handler lets us interrupt the
CPU emulation loop while the write to a pipe lets us avoid the
select/signal race condition.
    
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5451 c046a42c-6fe2-441c-8c8c-71466251a162
2008-10-08 19:50:24 +00:00
aliguori da3d9c5b46 Fix the build on non-Linux systems
It turns out, we're never reading from the signalfd() which is causing it to
remain readable forever.  I'll fix this up but I thought I'd commit this fix
in the interim.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5194 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-11 14:18:56 +00:00
aliguori bcdf9b4d16 Add missing files from previous commit.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5188 c046a42c-6fe2-441c-8c8c-71466251a162
2008-09-10 18:18:38 +00:00