qemu_error_sink can either point to a monitor or a file. In practice,
it always points to the current monitor if we have one, else to
stderr. Simply route errors to the current monitor or else to stderr,
and remove qemu_error_sink along with the functions to control it.
Actually, the old code switches the sink slightly later, in
handle_user_command() and handle_qmp_command(), than it gets switched
now, implicitly, by setting the current monitor in monitor_read() and
monitor_control_read(). Likewise, it switches back slightly earlier
(same places). Doesn't make a difference, because there are no calls
of qemu_error() in between.
Commits 376253ec..731b0364 introduced global variable cur_mon, which
points to the "default monitor" (if any), except during execution of
monitor_read() or monitor_control_read() it points to the monitor from
which we're reading instead (the "current monitor"). Monitor command
handlers run within monitor_read() or monitor_control_read().
Default monitor and current monitor are really separate things, and
squashing them together is confusing and error-prone.
For instance, usb_host_scan() can run both in "info usbhost" and
periodically via usb_host_auto_check(). It prints to cur_mon, which
is what we want in the former case: the monitor executing "info
usbhost". But since that's the default monitor in the latter case, it
periodically spams the default monitor there.
A few places use cur_mon to log stuff to the default monitor. If we
ever log something while cur_mon points to current monitor instead of
default monitor, the log temporarily "jumps" to another monitor.
Whether that can or cannot happen isn't always obvious.
Maybe logging to the default monitor (which may not even exist) is a
bad idea, and we should log to stderr or a logfile instead. But
that's outside the scope of this commit.
Change cur_mon to point to the current monitor. Create new
default_mon to point to the default monitor. Update users of cur_mon
accordingly.
This fixes the periodical spamming of the default monitor by
usb_host_scan(). It also stops "log jumping", should that problem
exist.
It's emitted whenever the watchdog device's timer expires. The action
taken is provided in the 'data' member.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This event has been introduced in the first round of QMP commits,
turns out that it's based on the usage of the EXCP_DEBUG macro,
which has discussable semantics when exposed through QMP.
As libvirt doesn't use this, let's just drop it.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch application failed. My patch adds a cb() call in
do_balloon(), but the change in git has added the cb() call to
do_info_balloon(). That is causing qemu segfaults. Applying the
following should correct the damage. Thanks.
Fix for commit: 5c366a8a3d
The cb() call is needed in do_balloon(), not do_info_balloon().
Signed-off-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
It was broken by 09b9418c6d. (!env && !is_physical) != (!is_physical)
when env is true.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Arghh... Adding missing S-O-B
Hi Anthony. I wonder if there was a problem when importing my async
command handler patchset. Since the 'balloon' command completes
immediately, it must call the completion callback before returning.
That call was missing but is added by the patch below.
Signed-off-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Handlers can generate only one error in a call, we let the
programmer know if they brake this rule and clients will only
get the first generated error.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
QObject Monitor handlers should not call any Monitor print
function: they should only build objects, printing is done
by common code.
Current QMP code will ignore such calls, as we can't send
garbage to clients, additionally it will also emit an
undefined error on the assumption that print calls usually
report errors.
However, the right way to deal with this is to rely on a
return code. This has been fixed by other commit already.
Now, this commit drops the error from monitor_vprintf() and
adds a better debugging mechanism for those 'stray' prints:
we count them if debug is enabled and let the developer know
if a QObject handler is trying to print anything.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit verifies the following two rules specified by
Markus Armbruster:
1. If the handler returns failure, it must have passed an error.
If it didn't, it's broken. Report an internal error to the client,
and report the bug to the programmer.
2. If the handler returns success, it must not have passed an error.
If it did, it's broken. Report the error to the client, and report
the bug to the programmer.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
We can ignore calls to monitor_vprintf() in QMP mode and use
monitor_puts() directly in monitor_json_emitter().
This allows us to drop this ugly hack.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Add configure options (--enable-debug-mon and --disable-debug-mon)
plus the MON_DEBUG() macro.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Now that all handlers are converted to cmd_new_ret(), we can rename
it back to cmd_new(). But now it returns a value.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Not that trivial as the call chain also has to be modified.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Note that this function only fails in QMP, in the user Monitor
it prints the help text instead.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The following handlers always succeed and hence can be converted
to cmd_new_ret() in the same commit.
- do_stop()
- do_quit()
- do_system_reset()
- do_system_powerdown()
- do_migrate_cancel()
- do_qmp_capabilities()
- do_migrate_set_speed()
- do_migrate_set_downtime()
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
In order to implement the new error handling and debugging
mechanism for command handlers, we need to change the cmd_new()
callback to return a value.
This commit introduces cmd_new_ret(), which returns a value and
will be used only temporarily to handle the transition from
cmd_new().
That is, as soon as all command handlers are ported to cmd_new_ret(),
it will be renamed back to cmd_new() and the new error handling
and debugging mechanism will be added on top of it.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
QMP's chardev event callback doesn't call
json_message_parser_destroy() on CHR_EVENT_CLOSED. As the call
to json_message_parser_init() on CHR_EVENT_OPENED allocates memory,
we'are leaking on close.
Fix that by just calling json_message_parser_destroy() on
CHR_EVENT_CLOSED.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Ideally, Monitor code should report an error only once and
return the error information up the call chain.
To assure that this happens as expected and that no error is
lost, we have an assert() in qemu_error_internal().
However, we still have not fully converted handlers using
monitor_printf() to report errors. As there can be multiple
monitor_printf() calls on an error, the assertion is easily
triggered when debugging is enabled; and we will get a memory
leak if it's not.
The solution to this problem is to allow multiple faults by only
reporting the first one, and to release the additional error objects.
A better mechanism to report multiple errors to programmers is
underway.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
It's not needed to check the return of qobject_from_jsonf()
anymore, as an assert() has been added there.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
With this commit QMP will be started in Capabilities Negotiation
mode, where the only command allowed to run is 'qmp_capabilities'.
All other commands will return CommandNotFound error. Asynchronous
messages are not delivered either.
When 'qmp_capabilities' is successfully executed QMP enters in
Command mode, where all commands (except 'qmp_capabilities') are
allowed to run and asynchronous messages are delivered.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This command will be used to enable QMP capabilities advertised
by the capabilities array.
Note that it will be mandatory to issue this command in order
to make QMP functional (although this behavior is not being
enforced by this commit).
Also, as we don't have any capabilities yet, the new command
doesn't accept any arguments. I will postpone the decision for
a format for this until we get our first capability.
Finally, this command is visible from the user Monitor too, in
the meaning that you can execute it but it won't do anything.
Making it only visible in QMP is beyond this series' goal, as
it requires changes in unrelated places.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
With capability negotiation support clients will only have a chance
to check QEMU's version (ie. issue 'query-version') after the
negotiation procedure is done.
It might be useful to clients to check QEMU's version before
negotiating features, though.
To allow that, this commit adds the QEMU's version object to the
greeting message.
Not really sure this is needed, but doesn't hurt anyway.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit adds the basic definitions for the BLOCK_IO_ERROR
event, but actual event emission will be introduced by the
next commits.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This changes the error message from "Invalid CPU index" to "Invalid
parameter index" in the human monitor.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This is a double value with optional suffixes ms, us, ns. We'll need
this to get migrate_set_downtime() QMP-ready.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This is a double value with optional suffixes G, g, M, m, K, k. We'll
need this to get migrate_set_speed() QMP-ready.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Function is_async_return() added by commit 940cc30d0d assumes
that 'data', which is returned by handlers, is always a QDict.
This is not true, as QLists can also be returned, in this case
we'll get a segfault.
Fix that by checking if 'data' is a QDict.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
When using ballooning to manage overcommitted memory on a host, a system for
guests to communicate their memory usage to the host can provide information
that will minimize the impact of ballooning on the guests. The current method
employs a daemon running in each guest that communicates memory statistics to a
host daemon at a specified time interval. The host daemon aggregates this
information and inflates and/or deflates balloons according to the level of
host memory pressure. This approach is effective but overly complex since a
daemon must be installed inside each guest and coordinated to communicate with
the host. A simpler approach is to collect memory statistics in the virtio
balloon driver and communicate them directly to the hypervisor.
Signed-off-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Qemu has a number of commands that can operate asynchronously (savevm, migrate,
etc) and it will be getting more. For these commands, the user monitor needs
to be suspended, but QMP monitors could continue to to accept other commands.
This patch introduces a new command API that isolates the details of handling
different monitor types from the actual command execution.
A monitor command can use this API by implementing the mhandler.cmd_async
handler (or info_async if appropriate). This function is responsible for
submitting the command and does not return any data although it may raise
errors. When the command completes, the QMPCompletion callback should be
invoked with its opaque data and the command result.
The process for submitting and completing an asynchronous command is different
for QMP and user monitors. A user monitor must be suspended at submit time and
resumed at completion time. The user_print() function must be passed to the
QMPCompletion callback so the result can be displayed properly. QMP monitors
are simpler. No submit time setup is required. When the command completes,
monitor_protocol_emitter() writes the result in JSON format.
This API can also be used to implement synchronous commands. In this case, the
cmd_async handler should immediately call the QMPCompletion callback. It is my
hope that this new interface will work for all commands, leading to a
drastically simplified monitor.c once all commands are ported.
Signed-off-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The returned QObject is a QList of all buses. Each bus is
represented by a QDict, which has a key with a QList of all
PCI devices attached to it. Each device is represented by
a QDict.
As has happended to other complex conversions, it's hard to
split this commit as part of it are new functions which are
called by each other.
IMPORTANT: support for printing PCI bridge attached devices
is NOT part of this commit, it's going to be added by the
next commit, as it's untested.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
CC i386-softmmu/monitor.o
cc1: warnings being treated as errors
/usr/src/RPM/BUILD/qemu-0.11.92/monitor.c: In function 'do_memory_save':
/usr/src/RPM/BUILD/qemu-0.11.92/monitor.c:1318: error: ignoring return value of 'fwrite', declared with attribute warn_unused_result
/usr/src/RPM/BUILD/qemu-0.11.92/monitor.c: In function 'do_physical_memory_save':
/usr/src/RPM/BUILD/qemu-0.11.92/monitor.c:1345: error: ignoring return value of 'fwrite', declared with attribute warn_unused_result
make[1]: *** [monitor.o] Error 1
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
mon_get_cpu() can't return null pointer, because it passes its return
value to cpu_synchronize_state() first, which crashes if its argument
is null.
Remove the (pretty cheesy) handling of this non-existing error.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Commit f039a563f2 introduces
a regression as monitor_protocol_event() will return in
the first user Monitor it finds in the QLIST_FOREACH()
loop.
The right thing to do is to only delivery an asynchronous
event if the 'mon' is a QMP Monitor.
The aforementioned commit was an early version, if it was
applied to stable (it should) this one has to be applied
there too.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Markus Armbruster