The thread pool regulates itself: when idle, it kills threads until
empty, when in demand, it creates new threads until full. This behaviour
doesn't play well with latency sensitive workloads where the price of
creating a new thread is too high. For example, when paired with qemu's
'-mlock', or using safety features like SafeStack, creating a new thread
has been measured take multiple milliseconds.
In order to mitigate this let's introduce a new 'EventLoopBase'
property to set the thread pool size. The threads will be created during
the pool's initialization or upon updating the property's value, remain
available during its lifetime regardless of demand, and destroyed upon
freeing it. A properly characterized workload will then be able to
configure the pool to avoid any latency spikes.
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20220425075723.20019-4-nsaenzju@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
'event-loop-base' provides basic property handling for all 'AioContext'
based event loops. So let's define a new 'MainLoopClass' that inherits
from it. This will permit tweaking the main loop's properties through
qapi as well as through the command line using the '-object' keyword[1].
Only one instance of 'MainLoopClass' might be created at any time.
'EventLoopBaseClass' learns a new callback, 'can_be_deleted()' so as to
mark 'MainLoop' as non-deletable.
[1] For example:
-object main-loop,id=main-loop,aio-max-batch=<value>
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20220425075723.20019-3-nsaenzju@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Thread-Local Storage variables cannot be used directly from coroutine
code because the compiler may optimize TLS variable accesses across
qemu_coroutine_yield() calls. When the coroutine is re-entered from
another thread the TLS variables from the old thread must no longer be
used.
Use QEMU_DEFINE_STATIC_CO_TLS() for the current and leader variables.
I think coroutine-win32.c could get away with __thread because the
variables are only used in situations where either the stale value is
correct (current) or outside coroutine context (loading leader when
current is NULL). Due to the difficulty of being sure that this is
really safe in all scenarios it seems worth converting it anyway.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20220307153853.602859-4-stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Thread-Local Storage variables cannot be used directly from coroutine
code because the compiler may optimize TLS variable accesses across
qemu_coroutine_yield() calls. When the coroutine is re-entered from
another thread the TLS variables from the old thread must no longer be
used.
Use QEMU_DEFINE_STATIC_CO_TLS() for the current and leader variables.
The alloc_pool QSLIST needs a typedef so the return value of
get_ptr_alloc_pool() can be stored in a local variable.
One example of why this code is necessary: a coroutine that yields
before calling qemu_coroutine_create() to create another coroutine is
affected by the TLS issue.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20220307153853.602859-3-stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Thread-Local Storage variables cannot be used directly from coroutine
code because the compiler may optimize TLS variable accesses across
qemu_coroutine_yield() calls. When the coroutine is re-entered from
another thread the TLS variables from the old thread must no longer be
used.
Use QEMU_DEFINE_STATIC_CO_TLS() for the current and leader variables.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20220307153853.602859-2-stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The qemu_*block() functions are meant to be be used with sockets (the
win32 implementation expects SOCKET)
Over time, those functions where used with Win32 SOCKET or
file-descriptors interchangeably. But for portability, they must only be
used with socket-like file-descriptors. FDs can use
g_unix_set_fd_nonblocking() instead.
Rename the functions with "socket" in the name to prevent bad usages.
This is effectively reverting commit f9e8cacc55 ("oslib-posix:
rename socket_set_nonblock() to qemu_set_nonblock()").
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
GLib g_unix_open_pipe() is essentially like qemu_pipe(), available since
2.30.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
It is only used by block/file-posix.c, move it there.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
API available since glib 2.30. It also preserves errno.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Like -set and -readconfig, it would not really be too hard to
extend -writeconfig to parsing mechanisms other than QemuOpts.
However, the uses of -writeconfig are substantially more
limited, as it is generally easier to write the configuration
by hand in the first place. In addition, -writeconfig does
not even try to detect cases where it prints incorrect
syntax (for example if values have a quote in them, since
qemu_config_parse does not support any kind of escaping.
Just remove it.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414145721.326866-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The 'g_get_real_time' returns the number of microseconds since January
1, 1970 UTC, but 'g_date_time_new_from_unix_utc' needs the number of
seconds, so it will cause the invalid time input:
(process:279642): GLib-CRITICAL (recursed) **: g_date_time_format: assertion 'datetime != NULL' failed
Call function 'g_date_time_new_now_utc' instead, it has the same result
as 'g_date_time_new_from_unix_utc(g_get_real_time() / G_USEC_PER_SEC)';
Fixes: 73dab893b5 ("error-report: replace deprecated g_get_current_time() with glib >= 2.62")
Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220424105036.291370-1-haiyue.wang@intel.com>
Users requiring FIPS support must build QEMU with either the libgcrypt
or gnutls libraries as the crytography backend.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Simplify the function to only return the directory path. Callers are
adjusted to use the GLib function to build paths, g_build_filename().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-39-marcandre.lureau@redhat.com>
qemu_open_old(O_CREATE) should be replaced with qemu_create() which
handles Error reporting.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-38-marcandre.lureau@redhat.com>
Mostly for correctness.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-37-marcandre.lureau@redhat.com>
Use qemu_write_full() instead of open-coding a write loop.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-36-marcandre.lureau@redhat.com>
The function is specific to qemu-ga, no need to share it in QEMU.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Message-Id: <20220420132624.2439741-32-marcandre.lureau@redhat.com>
Since it depends on monitor code, and error_vprintf_unless_qmp() is
already there.
This will help to move error-report in a common subproject.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-31-marcandre.lureau@redhat.com>
Do not require the whole option machinery to handle keyval, as it is
used by QAPI alone, without the option API. And match the associated
unit name.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-24-marcandre.lureau@redhat.com>
Move QEMU-specific code to util/osdep.c, so cutils can become a common
subproject.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-22-marcandre.lureau@redhat.com>
The implementation depends on the OS. (and longer-term goal is to move
cutils to a common subproject)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-21-marcandre.lureau@redhat.com>
Add a new log flag, tid, to turn this feature on.
Require the log filename to be set, and to contain %d.
Do not allow tid to be turned off once it is on, nor let
the filename be change thereafter. This avoids the need
for signalling each thread to re-open on a name change.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-40-richard.henderson@linaro.org>
Use FILE* for global_file. We can perform an rcu_read on that
just as easily as RCUCloseFILE*. This simplifies a couple of
places, where previously we required taking the rcu_read_lock
simply to avoid racing to dereference RCUCloseFile->fd.
Only allocate the RCUCloseFile prior to call_rcu.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-39-richard.henderson@linaro.org>
s/QemuLogFile/RCUCloseFILE/
s/qemu_logfile_free/rcu_close_file/
Emphasize that this is only a carrier for passing a pointer
to call_rcu for closing, and not the real logfile.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-38-richard.henderson@linaro.org>
Merge the close from the changed_name block with the close
from the !need_to_open_file block.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-37-richard.henderson@linaro.org>
Only call is_daemonized once.
We require the result on all paths after this point.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-36-richard.henderson@linaro.org>
Rename to emphasize this covers the file-scope global variables.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-35-richard.henderson@linaro.org>
Rename to emphasize this is the file-scope global variable.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-34-richard.henderson@linaro.org>
Rename to emphasize this is the file-scope global variable.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-33-richard.henderson@linaro.org>
The only real use is in cpu_abort, where we have just
flushed the file via qemu_log_unlock, and are just about
to force-crash the application via abort. We do not
really need to close the FILE before the abort.
The two uses in test-logging.c can be handled with
qemu_set_log_filename_flags.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-32-richard.henderson@linaro.org>
Provide a function to set both filename and flags at
the same time. This is the common case at startup.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-28-richard.henderson@linaro.org>
Move QemuLogFile, qemu_logfile, and all inline functions into qemu/log.c.
No need to expose these implementation details in the api.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-26-richard.henderson@linaro.org>
Now that the log buffer is flushed after every qemu_log_unlock,
which includes every call to qemu_log, we do not need to force
line buffering (or unbuffering for windows). Block buffer the
entire loggable unit.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-21-richard.henderson@linaro.org>
All uses flush output immediately before or after qemu_log_unlock.
Instead of a separate call, move the flush into qemu_log_unlock.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-20-richard.henderson@linaro.org>
The only user of this feature, tcg_dump_ops, has been
converted to use fprintf directly.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-18-richard.henderson@linaro.org>
Avoid using QemuLogFile and RCU directly.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-17-richard.henderson@linaro.org>
This function can fail, which makes it more like ftrylockfile
or pthread_mutex_trylock than flockfile or pthread_mutex_lock,
so rename it.
To closer match the other trylock functions, release rcu_read_lock
along the failure path, so that qemu_log_unlock need not be called
on failure.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-8-richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-7-richard.henderson@linaro.org>
Do not force exit within qemu_set_log; return bool and pass
an Error value back up the stack as per usual.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-5-richard.henderson@linaro.org>
Per the recommendations in qapi/error.h, return false on failure.
Use the return value in the monitor, the only place we aren't
already passing error_fatal or error_abort.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-4-richard.henderson@linaro.org>
This buffering was introduced during the Paleozoic: 9fa3e85353.
There has never been an explanation as to why we may not allow
glibc to allocate the file buffer itself. We certainly have
many other uses of mmap and malloc during user-only startup,
so presumably whatever the issue was, it has been fixed during
the preceeding 18 years.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-2-richard.henderson@linaro.org>
In this case there is no need to call pthread_cond_timedwait; the
function is just a trywait and waiting on the condition variable would
always time out.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now that QemuSemaphore is implemented through pthread_cond_t only, we can use
QemuCond and QemuMutex to make the code smaller. Features such as mutex
tracing and CLOCK_MONOTONIC timedwait are supported in qemu-sem naturally.
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Message-Id: <20220222090507.2028-4-longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use CLOCK_MONOTONIC, so the timeout isn't affected by changes to
the system time. It depends on the pthread_condattr_setclock(),
while some systems(e.g. mac os) does not support it, so the behavior
won't change in these systems.
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Message-Id: <20220222090507.2028-3-longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
POSIX specifies an absolute time for sem_timedwait(), it would be
affected if the system time is changing, but there is not a relative
time or monotonic clock version of sem_timedwait, so we cannot gain
from POSIX semaphore any more.
An alternative way is to use sem_trywait + usleep, maybe we can
remove CONFIG_SEM_TIMEDWAIT in this way? No, because some systems
(e.g. mac os) mark the sem_xxx API as deprecated.
So maybe remove the usage of POSIX semaphore and turn to use the
pthread variant for all systems looks better.
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Message-Id: <20220222090507.2028-2-longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Nicolas Saenz Julienne
Stefan Hajnoczi
Marc-André Lureau
Paolo Bonzini
Haiyue Wang
Daniel P. Berrangé
Richard Henderson
Longpeng(Mike)