Now that do have a nicer interface to work against we can add Linux native
AIO support. It's an extremly thing layer just setting up an iocb for
the io_submit system call in the submission path, and registering an
eventfd with the qemu poll handler to do complete the iocbs directly
from there.
This started out based on Anthony's earlier AIO patch, but after
estimated 42,000 rewrites and just as many build system changes
there's not much left of it.
To enable native kernel aio use the aio=native sub-command on the
drive command line. I have also added an option to qemu-io to
test the aio support without needing a guest.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Once there, move to a proper test to see if we are going to use it or not
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Extra error message is only given if --enable-kvm was given
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
All other features are named foo and enabled with --enable-foo.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Once there, remove extra check for package and output if bluez was found or not as the other features
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Straightforward implementation. This syscall is rare enough that we
don't need to support the odder cases, just disable it if host glibc
is too old.
Signed-off-by: Riku Voipio <riku.voipio@iki.fi>
As requested by Anthony make pthreads mandatory. This means we will always
have AIO available on posix hosts, and it will also allow enabling the I/O
thread unconditionally once it's ready.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
kqemu introduces a number of restrictions on the i386 target. The worst is that
it prevents large memory from working in the default build.
Furthermore, kqemu is fundamentally flawed in a number of ways. It relies on
the TSC as a time source which will not be reliable on a multiple processor
system in userspace. Since most modern processors are multicore, this severely
limits the utility of kqemu.
kvm is a viable alternative for people looking to accelerate qemu and has the
benefit of being supported by the upstream Linux kernel. If someone can
implement work arounds to remove the restrictions introduced by kqemu, I'm
happy to avoid and/or revert this patch.
N.B. kqemu will still function in the 0.11 series but this patch removes it from
the 0.12 series.
Paul, please Ack or Nack this patch.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Second attempt failed due to $_ not being standard and as such it's
interpretation by certain shells when they were symlinked to /bin/sh
and invoked as such led to unpredictable results. So instead of trying
to be clever just use /bin/sh directly (That's what direct execution
would have led to anyway)
Hopefully this time nothing will break (Mingw?)
Thanks to Jordan Justen for report and analysis.
[Previous attempt (THISSHELL one) deserves a credit but reporter is
too humble]
Signed-off-by: malc <av1474@comtv.ru>
http://www.opengroup.org/onlinepubs/7990989775/xbd/envvar.html
<quote>
SHELL
A pathname of the user's preferred command language
interpreter. If this interpreter does not conform to the XSI Shell
Command Language in the XCU specification, Shell Command Language,
utilities may behave differently from those described in this
specification set.
</quote>
So using shells for users who prefer csh variants is a no go.
