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>
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
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
Marcelo Tosatti