There is a small chance that iothread_stop() hangs as follows:
Thread 3 (Thread 0x7f63eba5f700 (LWP 16105)):
#0 0x00007f64012c09b6 in ppoll () at /lib64/libc.so.6
#1 0x000055959992eac9 in ppoll (__ss=0x0, __timeout=0x0, __nfds=<optimized out>, __fds=<optimized out>) at /usr/include/bits/poll2.h:77
#2 0x000055959992eac9 in qemu_poll_ns (fds=<optimized out>, nfds=<optimized out>, timeout=<optimized out>) at util/qemu-timer.c:322
#3 0x0000559599930711 in aio_poll (ctx=0x55959bdb83c0, blocking=blocking@entry=true) at util/aio-posix.c:629
#4 0x00005595996806fe in iothread_run (opaque=0x55959bd78400) at iothread.c:59
#5 0x00007f640159f609 in start_thread () at /lib64/libpthread.so.0
#6 0x00007f64012cce6f in clone () at /lib64/libc.so.6
Thread 1 (Thread 0x7f640b45b280 (LWP 16103)):
#0 0x00007f64015a0b6d in pthread_join () at /lib64/libpthread.so.0
#1 0x00005595999332ef in qemu_thread_join (thread=<optimized out>) at util/qemu-thread-posix.c:547
#2 0x00005595996808ae in iothread_stop (iothread=<optimized out>) at iothread.c:91
#3 0x000055959968094d in iothread_stop_iter (object=<optimized out>, opaque=<optimized out>) at iothread.c:102
#4 0x0000559599857d97 in do_object_child_foreach (obj=obj@entry=0x55959bdb8100, fn=fn@entry=0x559599680930 <iothread_stop_iter>, opaque=opaque@entry=0x0, recurse=recurse@entry=false) at qom/object.c:852
#5 0x0000559599859477 in object_child_foreach (obj=obj@entry=0x55959bdb8100, fn=fn@entry=0x559599680930 <iothread_stop_iter>, opaque=opaque@entry=0x0) at qom/object.c:867
#6 0x0000559599680a6e in iothread_stop_all () at iothread.c:341
#7 0x000055959955b1d5 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4913
The relevant code from iothread_run() is:
while (!atomic_read(&iothread->stopping)) {
aio_poll(iothread->ctx, true);
and iothread_stop():
iothread->stopping = true;
aio_notify(iothread->ctx);
...
qemu_thread_join(&iothread->thread);
The following scenario can occur:
1. IOThread:
while (!atomic_read(&iothread->stopping)) -> stopping=false
2. Main loop:
iothread->stopping = true;
aio_notify(iothread->ctx);
3. IOThread:
aio_poll(iothread->ctx, true); -> hang
The bug is explained by the AioContext->notify_me doc comments:
"If this field is 0, everything (file descriptors, bottom halves,
timers) will be re-evaluated before the next blocking poll(), thus the
event_notifier_set call can be skipped."
The problem is that "everything" does not include checking
iothread->stopping. This means iothread_run() will block in aio_poll()
if aio_notify() was called just before aio_poll().
This patch fixes the hang by replacing aio_notify() with
aio_bh_schedule_oneshot(). This makes aio_poll() or g_main_loop_run()
to return.
Implementing this properly required a new bool running flag. The new
flag prevents races that are tricky if we try to use iothread->stopping.
Now iothread->stopping is purely for iothread_stop() and
iothread->running is purely for the iothread_run() thread.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171207201320.19284-6-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The VM.add_object() method can be used to add IOThreads or memory
backend objects.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171207201320.19284-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When a node is already associated with a BlockBackend the
x-blockdev-set-iothread command refuses to set the IOThread. This is to
prevent accidentally changing the IOThread when the nodes are in use.
When the nodes are created with -drive they automatically get a
BlockBackend. In that case we know nothing is using them yet and it's
safe to set the IOThread. Add a force boolean to override the check.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171207201320.19284-4-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
See the patch for why nested AioContext locking is no longer allowed.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171207201320.19284-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
BDRV_POLL_WHILE() does not support recursive AioContext locking. It
only releases the AioContext lock once regardless of how many times the
caller has acquired it. This results in a hang since the IOThread does
not make progress while the AioContext is still locked.
The following steps trigger the hang:
$ qemu-system-x86_64 -M accel=kvm -m 1G -cpu host \
-object iothread,id=iothread0 \
-device virtio-scsi-pci,iothread=iothread0 \
-drive if=none,id=drive0,file=test.img,format=raw \
-device scsi-hd,drive=drive0 \
-drive if=none,id=drive1,file=test.img,format=raw \
-device scsi-hd,drive=drive1
$ qemu-system-x86_64 ...same options... \
-incoming tcp::1234
(qemu) migrate tcp:127.0.0.1:1234
...hang...
Tested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171207201320.19284-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
virtio-blk logical block size should never be larger than physical block
size because it doesn't make sense to have such configurations. QEMU doesn't
have a way to effectively express this condition; the best it can do is
report the physical block exponent as 0 - indicating the logical block size
equals the physical block size.
This is identical to commit 3da023b582
but applied to virtio-blk (instead of virtio-scsi).
Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Ameya More <ameya.more@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 773169891f9f2deb4cb7c4ef2655580dbe24c1d1.1513005190.git.mark.kanda@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Depending on the configuration, it can be beneficial to adjust the virtio-blk
queue size to something other than the current default of 128. Add a new
property to make the queue size configurable.
Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ameya More <ameya.more@oracle.com>
Message-id: 52e6d742811f10dbd16e996e86cf375b9577c187.1513005190.git.mark.kanda@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
QMP 'transaction' blockdev-snapshot-sync with multiple disks in an
IOThread is an untested code path. Several bugs have been found in
connection with this command. This patch adds a test case to prevent
future regressions.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-10-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Currently there is no easy way for iotests to ensure that a BDS is bound
to a particular IOThread. Normally the virtio-blk device calls
blk_set_aio_context() when dataplane is enabled during guest driver
initialization. This never happens in iotests since -machine
accel=qtest means there is no guest activity (including device driver
initialization).
This patch adds a QMP command to explicitly assign IOThreads in test
cases. See qapi/block-core.json for a description of the command.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-9-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Encapsulate IOThread QOM object lookup so that callers don't need to
know how and where IOThread objects live.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-8-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The dirty bitmap actions in qmp_transaction have not used AioContext
since the dirty bitmap locking discipline was introduced in commit
2119882c7e ("block: introduce
dirty_bitmap_mutex"). Remove the unused field.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-7-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-6-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-4-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
It is not necessary to hold AioContext across transactions anymore since
bdrv_drained_begin/end() is used to keep the nodes quiesced. In fact,
using the AioContext lock for this purpose was always buggy.
This patch reduces the scope of AioContext locked regions. This is not
just a cleanup but also fixes hangs that occur in BDRV_POLL_WHILE()
because it is unware of recursive locking and does not release the
AioContext the necessary number of times to allow progress to be made.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
bdrv_unref() requires the AioContext lock because bdrv_flush() uses
BDRV_POLL_WHILE(), which assumes the AioContext is currently held. If
BDRV_POLL_WHILE() runs without AioContext held the
pthread_mutex_unlock() call in aio_context_release() fails.
This patch moves bdrv_unref() into the AioContext locked region to solve
the following pthread_mutex_unlock() failure:
#0 0x00007f566181969b in raise () at /lib64/libc.so.6
#1 0x00007f566181b3b1 in abort () at /lib64/libc.so.6
#2 0x00005592cd590458 in error_exit (err=<optimized out>, msg=msg@entry=0x5592cdaf6d60 <__func__.23977> "qemu_mutex_unlock") at util/qemu-thread-posix.c:36
#3 0x00005592cd96e738 in qemu_mutex_unlock (mutex=mutex@entry=0x5592ce9505e0) at util/qemu-thread-posix.c:96
#4 0x00005592cd969b69 in aio_context_release (ctx=ctx@entry=0x5592ce950580) at util/async.c:507
#5 0x00005592cd8ead78 in bdrv_flush (bs=bs@entry=0x5592cfa87210) at block/io.c:2478
#6 0x00005592cd89df30 in bdrv_close (bs=0x5592cfa87210) at block.c:3207
#7 0x00005592cd89df30 in bdrv_delete (bs=0x5592cfa87210) at block.c:3395
#8 0x00005592cd89df30 in bdrv_unref (bs=0x5592cfa87210) at block.c:4418
#9 0x00005592cd6b7f86 in qmp_transaction (dev_list=<optimized out>, has_props=<optimized out>, props=<optimized out>, errp=errp@entry=0x7ffe4a1fc9d8) at blockdev.c:2308
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Commit 1351d1ec89 ("qdev: drop iothread
property type") forgot to remove this include.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20171205133954.31006-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The function name of usb_msd_{realize,unrealize}_*,
usb_msd_class_initfn_* are unusual. Rename it to
usb_msd_*_{realize,unrealize}, usb_msd_class_*_initfn.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 11e6003433abce35f3f4970e1acc71ee92dbcf51.1511317952.git.maozy.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
[Drop virtio_blk_data_plane_create() change that misinterprets return
value when the virtio transport does not support dataplane.
--Stefan]
Cc: John Snow <jsnow@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: e77848d3735ba590f23ffbf8094379c646c33d79.1511317952.git.maozy.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When the function no success value to transmit, it usually make the
function return void. It has turned out not to be a success, because
it means that the extra local_err variable and error_propagate() will
be needed. It leads to cumbersome code, therefore, transmit success/
failure in the return value is worth.
So fix the return type of blkconf_apply_backend_options(),
blkconf_geometry() and virtio_blk_data_plane_create() to avoid it.
Cc: John Snow <jsnow@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: ac0edc1fc70c4457e5cec94405eb7d1f89f9c2c1.1511317952.git.maozy.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Convert nvme_init() to realize and rename it to nvme_realize().
Cc: John Snow <jsnow@redhat.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Message-id: 2882e72d795e04cbe2120f569d551aef2467ac60.1511317952.git.maozy.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The AioContext pointer argument to co_aio_sleep_ns() is only used for
the sleep timer. It does not affect where the caller coroutine is
resumed.
Due to changes to coroutine and AIO APIs it is now possible to drop the
AioContext pointer argument. This is safe to do since no caller has
specific requirements for which AioContext the timer must run in.
This patch drops the AioContext pointer argument and renames the
function to simplify the API.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171109102652.6360-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If we've already raised an exception (and set NORETURN),
do not emit unreachable code to raise a debug exception.
Note that gen_goto_tb takes single-stepping into account.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170907185057.23421-4-richard.henderson@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
As for other targets, cmpxchg isn't quite right for ll/sc,
suffering from an ABA race, but is sufficient to implement
portable atomic operations.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170907185057.23421-2-richard.henderson@linaro.org>
[aurel32: fix whitespace]
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
This fixes bug #1735384 while running java under qemu-sh4. When debug
was enabled it showed a problem with TCG temps. Once fixed I was able
to run java -version normally.
Cc: qemu-stable@nongnu.org
Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20171206093050.25308-1-alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
If curl_global_init() fails, per the documentation no other curl
functions may be called, so make sure to check the return value.
Also, some minor changes to the initialization latch variable 'inited':
- Make it static in the file, for clarity
- Change the name for clarity
- Make it a bool
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
No functional changes, just whitespace manipulation.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
'tag' is already checked in the lines immediately preceding this check,
and set to non-NULL if NULL. No need to check again, it hasn't changed.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
If users set an unreasonably low speed (like one byte per second), the
calculated delay may exceed many hours. While we like to punish users
for asking for stupid things, we do also like to allow users to correct
their wicked ways.
When a user provides a new speed, kick the job to allow it to recalculate
its delay.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20171213204611.26276-1-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
We can use copy_bitmap instead of sync_bitmap. copy_bitmap is
initialized from sync_bitmap and it is more informative: we will not try
to process data, that is already in progress (by write notifier).
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 20171012135313.227864-6-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
Set fake progress for non-dirty clusters in copy_bitmap initialization,
to. It simplifies code and allows further refactoring.
This patch changes user's view of backup progress, but formally it
doesn't changed: progress hops are just moved to the beginning.
Actually it's just a point of view: when do we actually skip clusters?
We can say in the very beginning, that we skip these clusters and do
not think about them later.
Of course, if go through disk sequentially, it's logical to say, that
we skip clusters between copied portions to the left and to the right
of them. But even now copying progress is not sequential because of
write notifiers. Future patches will introduce new backup architecture
which will do copying in several coroutines in parallel, so it will
make no sense to publish fake progress by parts in parallel with
other copying requests.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 20171012135313.227864-5-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
We should not copy non-dirty clusters in write notifiers. So,
initialize copy_bitmap from sync_bitmap.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20171012135313.227864-4-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
Use HBitmap copy_bitmap instead of done_bitmap. This is needed to
improve incremental backup in following patches and to unify backup
loop for full/incremental modes in future patches.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20171012135313.227864-3-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
The function searches for next zero bit.
Also add interface for BdrvDirtyBitmap and unit test.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20171012135313.227864-2-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
Recent Linux kernel provides separate tracefs which doesn't need to be
mounted on the debugfs. Although most systems mount it at the
traditional place on the debugfs, it'd be safer to check tracefs first.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The find_debugfs() can be shared to find a different filesystem like
tracefs. So make it more general and rename to find_mount().
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The return vale of find_debugfs() is 1 if it could find a mount point of
debugfs. It can be saved in the while loop instead of checking it again.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
It's a x86-only device, so it does not make sense to keep it
in the shared misc folder.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
It's a x86-only device, so it does not make sense to keep it
in the shared misc folder.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
and remove the old i386/pc dependency.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>