iothread: Remove unused Error** argument in aio_context_set_aio_params

aio_context_set_aio_params() doesn't use its undocumented
Error** argument. Remove it to simplify.

Note this removes a use of

iothread: Remove unused Error** argument in aio_context_set_aio_params

aio_context_set_aio_params() doesn't use its undocumented
Error** argument. Remove it to simplify.

Note this removes a use of "unchecked Error**" in
iothread_set_aio_context_params().

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20231120171806.19361-1-philmd@linaro.org>

show more ...

aio: remove aio_disable_external() API

All callers now pass is_external=false to aio_set_fd_handler() and
aio_set_event_notifier(). The aio_disable_external() API that
temporarily disables fd handle

aio: remove aio_disable_external() API

All callers now pass is_external=false to aio_set_fd_handler() and
aio_set_event_notifier(). The aio_disable_external() API that
temporarily disables fd handlers that were registered is_external=true
is therefore dead code.

Remove aio_disable_external(), aio_enable_external(), and the
is_external arguments to aio_set_fd_handler() and
aio_set_event_notifier().

The entire test-fdmon-epoll test is removed because its sole purpose was
testing aio_disable_external().

Parts of this patch were generated using the following coccinelle
(https://coccinelle.lip6.fr/) semantic patch:

@@
expression ctx, fd, is_external, io_read, io_write, io_poll, io_poll_ready, opaque;
@@
- aio_set_fd_handler(ctx, fd, is_external, io_read, io_write, io_poll, io_poll_ready, opaque)
+ aio_set_fd_handler(ctx, fd, io_read, io_write, io_poll, io_poll_ready, opaque)

@@
expression ctx, notifier, is_external, io_read, io_poll, io_poll_ready;
@@
- aio_set_event_notifier(ctx, notifier, is_external, io_read, io_poll, io_poll_ready)
+ aio_set_event_notifier(ctx, notifier, io_read, io_poll, io_poll_ready)

Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230516190238.8401-21-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

win32: avoid mixing SOCKET and file descriptor space

Until now, a win32 SOCKET handle is often cast to an int file
descriptor, as this is what other OS use for sockets. When necessary,
QEMU eventual

win32: avoid mixing SOCKET and file descriptor space

Until now, a win32 SOCKET handle is often cast to an int file
descriptor, as this is what other OS use for sockets. When necessary,
QEMU eventually queries whether it's a socket with the help of
fd_is_socket(). However, there is no guarantee of conflict between the
fd and SOCKET space. Such conflict would have surprising consequences,
we shouldn't mix them.

Also, it is often forgotten that SOCKET must be closed with
closesocket(), and not close().

Instead, let's make the win32 socket wrapper functions return and take a
file descriptor, and let util/ wrappers do the fd/SOCKET conversion as
necessary. A bit of adaptation is necessary in io/ as well.

Unfortunately, we can't drop closesocket() usage, despite
_open_osfhandle() documentation claiming transfer of ownership, testing
shows bad behaviour if you forget to call closesocket().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.4103554-15-marcandre.lureau@redhat.com>

show more ...

aio/win32: aio_set_fd_handler() only supports SOCKET

Let's check if the argument is actually a SOCKET, else report an error
and return.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com

aio/win32: aio_set_fd_handler() only supports SOCKET

Let's check if the argument is actually a SOCKET, else report an error
and return.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.4103554-10-marcandre.lureau@redhat.com>

show more ...

aio: make aio_set_fd_poll() static to aio-posix.c

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.410355

aio: make aio_set_fd_poll() static to aio-posix.c

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.4103554-9-marcandre.lureau@redhat.com>

show more ...

win32/socket: introduce qemu_socket_select() helper

This is a wrapper for WSAEventSelect, with Error handling. By default,
it will produce a warning, so callers don't have to be modified
now, and ye

win32/socket: introduce qemu_socket_select() helper

This is a wrapper for WSAEventSelect, with Error handling. By default,
it will produce a warning, so callers don't have to be modified
now, and yet we can spot potential mis-use.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.4103554-7-marcandre.lureau@redhat.com>

show more ...

util/aio-win32: Correct the event array size in aio_poll()

WaitForMultipleObjects() can only wait for MAXIMUM_WAIT_OBJECTS
object handles. Correct the event array size in aio_poll() and
add a assert

util/aio-win32: Correct the event array size in aio_poll()

WaitForMultipleObjects() can only wait for MAXIMUM_WAIT_OBJECTS
object handles. Correct the event array size in aio_poll() and
add a assert() to ensure it does not cause out of bound access.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221019102015.2441622-3-bmeng.cn@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

show more ...

Remove qemu-common.h include from most units

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-33-marcandre.lureau@redhat.com>
Signed-off-by: Paolo B

Remove qemu-common.h include from most units

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-33-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

show more ...

aio-posix: split poll check from ready handler

Adaptive polling measures the execution time of the polling check plus
handlers called when a polled event becomes ready. Handlers can take a
significa

aio-posix: split poll check from ready handler

Adaptive polling measures the execution time of the polling check plus
handlers called when a polled event becomes ready. Handlers can take a
significant amount of time, making it look like polling was running for
a long time when in fact the event handler was running for a long time.

For example, on Linux the io_submit(2) syscall invoked when a virtio-blk
device's virtqueue becomes ready can take 10s of microseconds. This
can exceed the default polling interval (32 microseconds) and cause
adaptive polling to stop polling.

By excluding the handler's execution time from the polling check we make
the adaptive polling calculation more accurate. As a result, the event
loop now stays in polling mode where previously it would have fallen
back to file descriptor monitoring.

The following data was collected with virtio-blk num-queues=2
event_idx=off using an IOThread. Before:

168k IOPS, IOThread syscalls:

9837.115 ( 0.020 ms): IO iothread1/620155 io_submit(ctx_id: 140512552468480, nr: 16, iocbpp: 0x7fcb9f937db0) = 16
9837.158 ( 0.002 ms): IO iothread1/620155 write(fd: 103, buf: 0x556a2ef71b88, count: 8) = 8
9837.161 ( 0.001 ms): IO iothread1/620155 write(fd: 104, buf: 0x556a2ef71b88, count: 8) = 8
9837.163 ( 0.001 ms): IO iothread1/620155 ppoll(ufds: 0x7fcb90002800, nfds: 4, tsp: 0x7fcb9f1342d0, sigsetsize: 8) = 3
9837.164 ( 0.001 ms): IO iothread1/620155 read(fd: 107, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.174 ( 0.001 ms): IO iothread1/620155 read(fd: 105, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.176 ( 0.001 ms): IO iothread1/620155 read(fd: 106, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.209 ( 0.035 ms): IO iothread1/620155 io_submit(ctx_id: 140512552468480, nr: 32, iocbpp: 0x7fca7d0cebe0) = 32

174k IOPS (+3.6%), IOThread syscalls:

9809.566 ( 0.036 ms): IO iothread1/623061 io_submit(ctx_id: 140539805028352, nr: 32, iocbpp: 0x7fd0cdd62be0) = 32
9809.625 ( 0.001 ms): IO iothread1/623061 write(fd: 103, buf: 0x5647cfba5f58, count: 8) = 8
9809.627 ( 0.002 ms): IO iothread1/623061 write(fd: 104, buf: 0x5647cfba5f58, count: 8) = 8
9809.663 ( 0.036 ms): IO iothread1/623061 io_submit(ctx_id: 140539805028352, nr: 32, iocbpp: 0x7fd0d0388b50) = 32

Notice that ppoll(2) and eventfd read(2) syscalls are eliminated because
the IOThread stays in polling mode instead of falling back to file
descriptor monitoring.

As usual, polling is not implemented on Windows so this patch ignores
the new io_poll_read() callback in aio-win32.c.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-2-stefanha@redhat.com

[Fixed up aio_set_event_notifier() calls in
tests/unit/test-fdmon-epoll.c added after this series was queued.
--Stefan]

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

iothread: add aio-max-batch parameter

The `aio-max-batch` parameter will be propagated to AIO engines
and it will be used to control the maximum number of queued requests.

When there are in queue a

iothread: add aio-max-batch parameter

The `aio-max-batch` parameter will be propagated to AIO engines
and it will be used to control the maximum number of queued requests.

When there are in queue a number of requests equal to `aio-max-batch`,
the engine invokes the system call to forward the requests to the kernel.

This parameter allows us to control the maximum batch size to reduce
the latency that requests might accumulate while queued in the AIO
engine queue.

If `aio-max-batch` is equal to 0 (default value), the AIO engine will
use its default maximum batch size value.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20210721094211.69853-3-sgarzare@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

qmp: fix aio_poll() assertion failure on Windows

Commit 9ce44e2ce2 "qmp: Move dispatcher to a coroutine" modified
aio_poll() in util/aio-posix.c to avoid an assertion failure. This
change is missing

qmp: fix aio_poll() assertion failure on Windows

Commit 9ce44e2ce2 "qmp: Move dispatcher to a coroutine" modified
aio_poll() in util/aio-posix.c to avoid an assertion failure. This
change is missing in util/aio-win32.c.

Apply the changes to util/aio-posix.c to util/aio-win32.c too.
This fixes an assertion failure on Windows whenever QEMU exits.

$ ./qemu-system-x86_64.exe -machine pc,accel=tcg -display gtk
**
ERROR:../qemu/util/aio-win32.c:337:aio_poll: assertion failed:
(in_aio_context_home_thread(ctx))
Bail out! ERROR:../qemu/util/aio-win32.c:337:aio_poll: assertion
failed: (in_aio_context_home_thread(ctx))

Fixes: 9ce44e2ce2 ("qmp: Move dispatcher to a coroutine")
Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20201021064033.8600-1-vr_qemu@t-online.de>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

qemu/atomic.h: rename atomic_ to qatomic_

clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when

qemu/atomic.h: rename atomic_ to qatomic_

clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:

$ CC=clang CXX=clang++ ./configure ... && make
../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)

Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.

This patch was generated using:

$ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
sort -u >/tmp/changed_identifiers
$ for identifier in $(</tmp/changed_identifiers); do
sed -i "s%\<$identifier\>%q$identifier%g" \
$(git grep -I -l "\<$identifier\>")
done

I manually fixed line-wrap issues and misaligned rST tables.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>

show more ...

tests: fixes aio-win32 about aio_remove_fd_handler, get it consistence with aio-posix.c

This is a fixes for
(C:\work\xemu\qemu\build\tests\test-aio-multithread.exe:19100): GLib-CRITICAL **: 23:03:24

tests: fixes aio-win32 about aio_remove_fd_handler, get it consistence with aio-posix.c

This is a fixes for
(C:\work\xemu\qemu\build\tests\test-aio-multithread.exe:19100): GLib-CRITICAL **: 23:03:24.965: g_source_remove_poll: assertion '!SOURCE_DESTROYED (source)' failed
ERROR test-aio-multithread - Bail out! GLib-FATAL-CRITICAL: g_source_remove_poll: assertion '!SOURCE_DESTROYED (source)' failed

(C:\work\xemu\qemu\build\tests\test-bdrv-drain.exe:21036): GLib-CRITICAL **: 23:03:29.861: g_source_remove_poll: assertion '!SOURCE_DESTROYED (source)' failed
ERROR test-bdrv-drain - Bail out! GLib-FATAL-CRITICAL: g_source_remove_poll: assertion '!SOURCE_DESTROYED (source)' failed

And the idea comes from https://patchwork.kernel.org/patch/9975239/

Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Message-Id: <20200915171234.236-19-luoyonggang@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

show more ...

aio-posix: disable fdmon-io_uring when GSource is used

The glib event loop does not call fdmon_io_uring_wait() so fd handlers
waiting to be submitted build up in the list. There is no benefit is
usi

aio-posix: disable fdmon-io_uring when GSource is used

The glib event loop does not call fdmon_io_uring_wait() so fd handlers
waiting to be submitted build up in the list. There is no benefit is
using io_uring when the glib GSource is being used, so disable it
instead of implementing a more complex fix.

This fixes a memory leak where AioHandlers would build up and increasing
amounts of CPU time were spent iterating them in aio_pending(). The
symptom is that guests become slow when QEMU is built with io_uring
support.

Buglink: https://bugs.launchpad.net/qemu/+bug/1877716
Fixes: 73fd282e7b6dd4e4ea1c3bbb3d302c8db51e4ccf ("aio-posix: add io_uring fd monitoring implementation")
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Oleksandr Natalenko <oleksandr@redhat.com>
Message-id: 20200511183630.279750-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

async: use explicit memory barriers

When using C11 atomics, non-seqcst reads and writes do not participate
in the total order of seqcst operations. In util/async.c and util/aio-posix.c,
in particul

async: use explicit memory barriers

When using C11 atomics, non-seqcst reads and writes do not participate
in the total order of seqcst operations. In util/async.c and util/aio-posix.c,
in particular, the pattern that we use

write ctx->notify_me write bh->scheduled
read bh->scheduled read ctx->notify_me
if !bh->scheduled, sleep if ctx->notify_me, notify

needs to use seqcst operations for both the write and the read. In
general this is something that we do not want, because there can be
many sources that are polled in addition to bottom halves. The
alternative is to place a seqcst memory barrier between the write
and the read. This also comes with a disadvantage, in that the
memory barrier is implicit on strongly-ordered architectures and
it wastes a few dozen clock cycles.

Fortunately, ctx->notify_me is never written concurrently by two
threads, so we can assert that and relax the writes to ctx->notify_me.
The resulting solution works and performs well on both aarch64 and x86.

Note that the atomic_set/atomic_read combination is not an atomic
read-modify-write, and therefore it is even weaker than C11 ATOMIC_RELAXED;
on x86, ATOMIC_RELAXED compiles to a locked operation.

Analyzed-by: Ying Fang <fangying1@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Ying Fang <fangying1@huawei.com>
Message-Id: <20200407140746.8041-6-pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

aio-posix: Fix concurrent aio_poll/set_fd_handler.

It is possible for an io_poll callback to be concurrently executed along
with an aio_set_fd_handlers. This can cause all sorts of problems, like
a

aio-posix: Fix concurrent aio_poll/set_fd_handler.

It is possible for an io_poll callback to be concurrently executed along
with an aio_set_fd_handlers. This can cause all sorts of problems, like
a NULL callback or a bad opaque pointer.

This changes set_fd_handlers so that it no longer modify existing handlers
entries and instead, always insert those after having proper initialisation.

Tested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Remy Noel <remy.noel@blade-group.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20181220152030.28035-3-remy.noel@blade-group.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

aio: Do aio_notify_accept only during blocking aio_poll

An aio_notify() pairs with an aio_notify_accept(). The former should
happen in the main thread or a vCPU thread, and the latter should be
done

aio: Do aio_notify_accept only during blocking aio_poll

An aio_notify() pairs with an aio_notify_accept(). The former should
happen in the main thread or a vCPU thread, and the latter should be
done in the IOThread.

There is one rare case that the main thread or vCPU thread may "steal"
the aio_notify() event just raised by itself, in bdrv_set_aio_context()
[1]. The sequence is like this:

main thread IO Thread
===============================================================
bdrv_drained_begin()
aio_disable_external(ctx)
aio_poll(ctx, true)
ctx->notify_me += 2
...
bdrv_drained_end()
...
aio_notify()
...
bdrv_set_aio_context()
aio_poll(ctx, false)
[1] aio_notify_accept(ctx)
ppoll() /* Hang! */

[1] is problematic. It will clear the ctx->notifier event so that
the blocked ppoll() will not return.

(For the curious, this bug was noticed when booting a number of VMs
simultaneously in RHV. One or two of the VMs will hit this race
condition, making the VIRTIO device unresponsive to I/O commands. When
it hangs, Seabios is busy waiting for a read request to complete (read
MBR), right after initializing the virtio-blk-pci device, using 100%
guest CPU. See also https://bugzilla.redhat.com/show_bug.cgi?id=1562750
for the original bug analysis.)

aio_notify() only injects an event when ctx->notify_me is set,
correspondingly aio_notify_accept() is only useful when ctx->notify_me
_was_ set. Move the call to it into the "blocking" branch. This will
effectively skip [1] and fix the hang.

Furthermore, blocking aio_poll is only allowed on home thread
(in_aio_context_home_thread), because otherwise two blocking
aio_poll()'s can steal each other's ctx->notifier event and cause
hanging just like described above.

Cc: qemu-stable@nongnu.org
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20180809132259.18402-3-famz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>

show more ...

iothread: fix epollfd leak in the process of delIOThread

When we call addIOThread, the epollfd created in aio_context_setup,
but not close it in the process of delIOThread, so the epollfd will leak.

iothread: fix epollfd leak in the process of delIOThread

When we call addIOThread, the epollfd created in aio_context_setup,
but not close it in the process of delIOThread, so the epollfd will leak.

Reorder the code in aio_epoll_disable and reuse it.

Signed-off-by: Jie Wang <wangjie88@huawei.com>
Message-Id: <1526517763-11108-1-git-send-email-wangjie88@huawei.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
[Mention change to aio_epoll_disable in commit message. - Fam]
Signed-off-by: Fam Zheng <famz@redhat.com>

show more ...

iothread: fix breakage on windows

OOB can enable iothread for parsing even on Windows. We need some tunes
to enable that on Windows otherwise it'll break Windows users. This
patch fixes the breaka

iothread: fix breakage on windows

OOB can enable iothread for parsing even on Windows. We need some tunes
to enable that on Windows otherwise it'll break Windows users. This
patch fixes the breakage on Windows with qemu-system-ppc.exe.

Reported-by: Howard Spoelstra <hsp.cat7@gmail.com>
Tested-by: Howard Spoelstra <hsp.cat7@gmail.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180322085630.23654-1-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

show more ...

util/aio-win32: Only select on what we are actually waiting for

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Phi

util/aio-win32: Only select on what we are actually waiting for

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 9307b70e9876c4e9e3c4478524a32a23a3d5dd05.1499368180.git.alistair.francis@xilinx.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

async: remove unnecessary inc/dec pairs

Pull the increment/decrement pair out of aio_bh_poll and into the
callers.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <p

async: remove unnecessary inc/dec pairs

Pull the increment/decrement pair out of aio_bh_poll and into the
callers.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-18-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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aio-posix: partially inline aio_dispatch into aio_poll

This patch prepares for the removal of unnecessary lockcnt inc/dec pairs.
Extract the dispatching loop for file descriptor handlers into a new

aio-posix: partially inline aio_dispatch into aio_poll

This patch prepares for the removal of unnecessary lockcnt inc/dec pairs.
Extract the dispatching loop for file descriptor handlers into a new
function aio_dispatch_handlers, and then inline aio_dispatch into
aio_poll.

aio_dispatch can now become void.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-17-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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block: explicitly acquire aiocontext in callbacks that need it

This covers both file descriptor callbacks and polling callbacks,
since they execute related code.

Reviewed-by: Stefan Hajnoczi <stefa

block: explicitly acquire aiocontext in callbacks that need it

This covers both file descriptor callbacks and polling callbacks,
since they execute related code.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-14-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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block: explicitly acquire aiocontext in timers that need it

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.

block: explicitly acquire aiocontext in timers that need it

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-13-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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aio: push aio_context_acquire/release down to dispatching

The AioContext data structures are now protected by list_lock and/or
they are walked with FOREACH_RCU primitives. There is no need anymore

aio: push aio_context_acquire/release down to dispatching

The AioContext data structures are now protected by list_lock and/or
they are walked with FOREACH_RCU primitives. There is no need anymore
to acquire the AioContext for the entire duration of aio_dispatch.
Instead, just acquire it before and after invoking the callbacks.
The next step is then to push it further down.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-12-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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