monitor_fdsets_cleanup() currently has three responsibilities:
1- Remove the fds that have been marked for removal(->removed=true) by
qmp_remove_fd(). This is overly complicated, but ok.
2- Remove any file descriptors that have been passed into QEMU and
never duplicated[1,2]. A file descriptor without duplicates
indicates that no part of QEMU has made use of it. This is
problematic because the current implementation does it only if the
guest is not running and the monitor is closed.
3- Remove/free fdsets that have become empty due to the above
removals. This is ok.
The scenario described in (2) is starting to show some cracks now that
we're trying to consume fds from the migration code:
- Doing cleanup every time the last monitor connection closes works to
reap unused fds, but also has the side effect of forcing the
management layer to pass the file descriptors again in case of a
disconnect/re-connect, if that happened to be the only monitor
connection.
Another side effect is that removing an fd with qmp_remove_fd() is
effectively delayed until the last monitor connection closes.
The usage of mon_refcount is also problematic because it's racy.
- Checking runstate_is_running() skips the cleanup unless the VM is
running and avoids premature cleanup of the fds, but also has the
side effect of blocking the legitimate removal of an fd via
qmp_remove_fd() if the VM happens to be in another state.
This affects qmp_remove_fd() and qmp_query_fdsets() in particular
because requesting a removal at a bad time (guest stopped) might
cause an fd to never be removed, or to be removed at a much later
point in time, causing the query command to continue showing the
supposedly removed fd/fdset.
Note that file descriptors that *have* been duplicated are owned by
the code that uses them and will be removed after qemu_close() is
called. Therefore we've decided that the best course of action to
avoid the undesired side-effects is to stop managing non-duplicated
file descriptors.
1- efb87c1697 ("monitor: Clean up fd sets on monitor disconnect")
2- ebe52b592d ("monitor: Prevent removing fd from set during init")
Reviewed-by: Peter Xu <peterx@redhat.com>
[fix logic mistake: s/fdset_free/fdset_free_if_empty]
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Clean up monitor_event to just use monitor_suspend/monitor_resume,
using mon->mux_out to protect against incorrect nesting (especially
on startup).
The only remaining case of reading suspend_cnt is in the can_read
callback, which is just advisory and can use qatomic_read.
As an extra benefit, mux_out is now simply protected by mon_lock.
Also, moving the prompt to the beginning of the main loop removes
it from the output in some error cases where QEMU does not actually
start successfully. It is not a full fix and it would be nice to
also remove the monitor heading, but this is already a small (though
unintentional) improvement.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The HMP monitor runs in the main loop thread. Calling
AIO_WAIT_WHILE(qemu_get_aio_context(), ...) from the main loop thread is
equivalent to AIO_WAIT_WHILE_UNLOCKED(NULL, ...) because neither unlocks
the AioContext and the latter's assertion that we're in the main loop
succeeds.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230309190855.414275-6-stefanha@redhat.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The auto completion does not work in some cases.
Case 1.
1. (qemu) info reg
2. Press 'Tab'.
3. It does not auto complete.
Case 2.
1. (qemu) block_resize flo
2. Press 'Tab'.
3. It does not auto complete 'floppy0'.
Since the readline_add_completion_of() may add any completion when
strlen(pfx) is zero, we remove the check with (name[0] == '\0') because
strlen() always returns zero in that case.
Fixes: 52f50b1e9f ("readline: Extract readline_add_completion_of() from monitor")
Cc: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Message-Id: <20230207045241.8843-1-dongli.zhang@oracle.com>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The next commit will move a caller of help_cmd() to a new file.
Including monitor/monitor-internal.h there just for help_cmd() feels
silly. Better to provide it in monitor/hmp.h suitably renamed.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-8-armbru@redhat.com>
monitor/misc.h has static add_completion_option(). It's useful
elsewhere in the monitor. Since it's not monitor-specific, move it to
util/readline.c renamed to readline_add_completion_of(), and put it to
use.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-7-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-2-armbru@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
This helps us construct strings elsewhere before echoing to the
monitor. It avoids having to jump through hoops like:
monitor_printf(mon, "%s", s->str);
It will be useful in following patches but for now convert all
existing plain "%s" printfs to use the _puts api.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220929114231.583801-33-alex.bennee@linaro.org>
The below is printed when printing help information in qemu-system-x86_64
command line, and when CONFIG_TRACE_LOG is enabled:
----------------------------
$ qemu-system-x86_64 -d help
... ...
trace:PATTERN enable trace events
Use "-d trace:help" to get a list of trace events.
----------------------------
However, the options of "trace:PATTERN" are only printed by
"qemu-system-x86_64 -d help", but missing in hmp "help log" command.
Fixes: c84ea00dc2 ("log: add "-d trace:PATTERN"")
Cc: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Message-Id: <20220831213943.8155-1-dongli.zhang@oracle.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
G_NORETURN was introduced in glib 2.68, fallback to G_GNUC_NORETURN in
glib-compat.
Note that this attribute must be placed before the function declaration
(bringing a bit of consistency in qemu codebase usage).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20220420132624.2439741-20-marcandre.lureau@redhat.com>
One less qemu-specific macro. It also helps to make some headers/units
only depend on glib, and thus moved in standalone projects eventually.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Adds support for the "-xs" parameter type, where "-x" denotes a flag
name and the "s" suffix indicates that this flag is supposed to take
an arbitrary string parameter.
These parameters are always optional, the entry in the qdict will be
omitted if the flag is not given.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
[FE: fixed typo pointed out by Eric Blake
use s instead of V to indicate string parameter]
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
Message-Id: <20220225084949.35746-2-f.ebner@proxmox.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This provides a foundation on which to convert simple HMP commands to
use QMP. The QMP implementation will generate formatted text targeted
for human consumption, returning it in the HumanReadableText data type.
The HMP command handler will simply print out the formatted string
within the HumanReadableText data type. Since this will be an entirely
formulaic action in the case of HMP commands taking no arguments, a
custom command handler is provided.
Thus instead of registering a 'cmd' callback for the HMP command, a
'cmd_info_hrt' callback is provided, which will simply be a pointer
to the QMP implementation.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Allow commands having a NULL cmd pointer, add a function to set the
pointer later. Use case: allow modules implement hmp commands.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-31-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Generalize the qdev_hotplug variable to the different phases of
machine initialization. We would like to allow different
monitor commands depending on the phase.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The preconfig state is only used if -incoming is not specified, which
makes the RunState state machine more tricky than it need be. However
there is already an equivalent condition which works even with -incoming,
namely qdev_hotplug. Use it instead of a separate runstate.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Combine the RUN_STATE_PRECONFIG and cmd_can_preconfig checks
into a single function, to avoid repeating the same expression
(or its negation after applying DeMorgan's rule) over and
over again.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
mon_get_cpu() is indirectly called monitor_parse_arguments() where
the current monitor isn't set yet. Instead of using monitor_cur(),
explicitly pass the Monitor pointer to the function.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201113114326.97663-2-kwolf@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Often, QMP command handlers are not only called to handle QMP commands,
but also from a corresponding HMP command handler. In order to give them
a consistent environment, optionally run HMP command handlers in a
coroutine, too.
The implementation is a lot simpler than in QMP because for HMP, we
still block the VM while the coroutine is running.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20201005155855.256490-11-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This way, a monitor command handler will still be able to access the
current monitor, but when it yields, all other code code will correctly
get NULL from monitor_cur().
This uses a hash table to map the coroutine pointer to the current
monitor of that coroutine. Outside of coroutine context, we associate
the current monitor with the leader coroutine of the current thread.
Approaches to implement some form of coroutine local storage directly in
the coroutine core code have been considered and discarded because they
didn't end up being much more generic than the hash table and their
performance impact on coroutines not using coroutine local storage was
unclear. As the block layer uses a coroutine per I/O request, this is a
fast path and we have to be careful. It's safest to just stay out of
this path with code only used by the monitor.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201005155855.256490-8-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The current monitor is updated relatively early in the command handling
code even though only the command handler actually needs it.
The current monitor will become coroutine-local later, so we can only
update it when we know in which coroutine the command will be exectued.
Move it to handle_hmp_command() where this information will be
available.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201005155855.256490-5-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
cur_mon really needs to be coroutine-local as soon as we move monitor
command handlers to coroutines and let them yield. As a first step, just
remove all direct accesses to cur_mon so that we can implement this in
the getter function later.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-4-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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>
Trying to attach a HMP monitor to a chardev that is already in use
results in a crash because monitor_init_hmp() passes &error_abort to
qemu_chr_fe_init():
$ ./x86_64-softmmu/qemu-system-x86_64 --chardev stdio,id=foo --mon foo --mon foo
QEMU 4.2.50 monitor - type 'help' for more information
(qemu) Unexpected error in qemu_chr_fe_init() at chardev/char-fe.c:220:
qemu-system-x86_64: --mon foo: Device 'foo' is in use
Abgebrochen (Speicherabzug geschrieben)
Fix this by allowing monitor_init_hmp() to return an error and passing
any error in qemu_chr_fe_init() to its caller instead of aborting.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200224143008.13362-19-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The Chardev events are listed in the QEMUChrEvent enum.
By using the enum in the IOEventHandler typedef we:
- make the IOEventHandler type more explicit (this handler
process out-of-band information, while the IOReadHandler
is in-band),
- help static code analyzers.
This patch was produced with the following spatch script:
@match@
expression backend, opaque, context, set_open;
identifier fd_can_read, fd_read, fd_event, be_change;
@@
qemu_chr_fe_set_handlers(backend, fd_can_read, fd_read, fd_event,
be_change, opaque, context, set_open);
@depends on match@
identifier opaque, event;
identifier match.fd_event;
@@
static
-void fd_event(void *opaque, int event)
+void fd_event(void *opaque, QEMUChrEvent event)
{
...
}
Then the typedef was modified manually in
include/chardev/char-fe.h.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20191218172009.8868-15-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The Chardev events are listed in the QEMUChrEvent enum. To be
able to use this enum in the IOEventHandler typedef, we need to
explicit an event ignored by this frontend, to silent the
following GCC warning:
CC monitor/hmp.o
monitor/hmp.c: In function ‘monitor_event’:
monitor/hmp.c:1330:5: error: enumeration value ‘CHR_EVENT_BREAK’ not handled in switch [-Werror=switch]
1330 | switch (event) {
| ^~~~~~
cc1: all warnings being treated as errors
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20191218172009.8868-13-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
sysemu/sysemu.h is a rather unfocused dumping ground for stuff related
to the system-emulator. Evidence:
* It's included widely: in my "build everything" tree, changing
sysemu/sysemu.h still triggers a recompile of some 1100 out of 6600
objects (not counting tests and objects that don't depend on
qemu/osdep.h, down from 5400 due to the previous two commits).
* It pulls in more than a dozen additional headers.
Split stuff related to run state management into its own header
sysemu/runstate.h.
Touching sysemu/sysemu.h now recompiles some 850 objects. qemu/uuid.h
also drops from 1100 to 850, and qapi/qapi-types-run-state.h from 4400
to 4200. Touching new sysemu/runstate.h recompiles some 500 objects.
Since I'm touching MAINTAINERS to add sysemu/runstate.h anyway, also
add qemu/main-loop.h.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-30-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
[Unbreak OS-X build]
Most callers know which monitor type they want to have. Instead of
calling monitor_init() with flags that can describe both types of
monitors, make monitor_init_{hmp,qmp}() public interfaces that take
specific bools instead of flags and call these functions directly.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20190613153405.24769-15-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Monitor.flags contains three different flags: One to distinguish HMP
from QMP; one specific to HMP (MONITOR_USE_READLINE) that is ignored
with QMP; and another one specific to QMP (MONITOR_USE_PRETTY) that is
ignored with HMP.
Split the flags field into three bools and move them to the right
subclass. Flags are still in use for the monitor_init() interface.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20190613153405.24769-14-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Move HMP infrastructure from monitor/misc.c to monitor/hmp.c. This is
code that can be shared for all targets, so compile it only once.
The amount of function and particularly extern variables in
monitor_int.h is probably a bit larger than it needs to be, but this way
no non-trivial code modifications are needed. The interfaces between HMP
and the monitor core can be cleaned up later.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20190613153405.24769-12-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Comment reformatted to make checkpatch.pl happy, #include <dirent.h>
moved to fix Windows build, superfluous #include dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
