aboutsummaryrefslogtreecommitdiff
path: root/util/qemu-thread-win32.c
AgeCommit message (Collapse)Author
2019-01-11build-sys: build with Vista API by defaultMarc-André Lureau
Both qemu & qga build with Vista API by default already, by defining _WIN32_WINNT 0x0600. Set it globally in osdep.h instead. This replaces WINVER by _WIN32_WINNT in osdep.h. WINVER doesn't seem to be really useful these days. (see also https://blogs.msdn.microsoft.com/oldnewthing/20070411-00/?p=27283) Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20181122110039.15972-4-marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23qsp: QEMU's Synchronization ProfilerEmilio G. Cota
The goal of this module is to profile synchronization primitives (i.e. mutexes, recursive mutexes and condition variables) so that scalability issues can be quickly diagnosed. Sync primitives are profiled by QSP based on the vaddr of the object accessed as well as the call site (file:line_nr). That means the same object called from two different call sites will be tracked in separate entries, which might be reported together or separately (see subsequent commit on call site coalescing). Some perf numbers: Host: Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz Command: taskset -c 0 tests/atomic_add-bench -d 5 -m - Before: 54.80 Mops/s - After: 54.75 Mops/s That is, a negligible slowdown due to the now indirect call to qemu_mutex_lock. Note that using a branch instead of an indirect call introduces a more severe slowdown (53.65 Mops/s, i.e. 2% slowdown). Enabling the profiler (with -p, added in this series) is more interesting: - No profiling: 54.75 Mops/s - W/ profiling: 12.53 Mops/s That is, a 4.36X slowdown. We can break down this slowdown by removing the get_clock calls or the entry lookup: - No profiling: 54.75 Mops/s - W/o get_clock: 25.37 Mops/s - W/o entry lookup: 19.30 Mops/s - W/ profiling: 12.53 Mops/s Signed-off-by: Emilio G. Cota <cota@braap.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-28qemu-thread: introduce qemu-thread-common.hPeter Xu
Introduce some hooks for the shared part of qemu thread between POSIX and Windows implementations. Note that in qemu_mutex_unlock_impl() we moved the call before unlock operation which should make more sense. And we don't need qemu_mutex_post_unlock() hook. Put all these shared hooks into the header files. It should be internal to qemu-thread but not for qemu-thread users, hence put into util/ directory. Reviewed-by: Emilio G. Cota <cota@braap.org> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20180425025459.5258-3-peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-16util/qemu-thread-*: add qemu_lock, locked and unlock trace eventsAlex Bennée
Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-04qemu-thread: Assert locks are initialized before usingFam Zheng
Not all platforms check whether a lock is initialized before used. In particular Linux seems to be more permissive than OSX. Check initialization state explicitly in our code to catch such bugs earlier. Signed-off-by: Fam Zheng <famz@redhat.com> Message-Id: <20170704122325.25634-1-famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-05trace: add qemu mutex lock and unlock trace eventsJose Ricardo Ziviani
These trace events were very useful to help me to understand and find a reordering issue in vfio, for example: qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc0, 0x2020c, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc4, 0xa0000, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 that also helped me to see the desired result after the fix: qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc0, 0x2000c, 4) vfio_region_write (0001:03:00.0:region1+0xc4, 0xb0000, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 So it could be a good idea to have these traces implemented. It's worth mentioning that they should be surgically enabled during the debugging, otherwise it can flood the trace logs with lock/unlock messages. How to use it: trace-event qemu_mutex_lock on|off trace-event qemu_mutex_unlock on|off or trace-event qemu_mutex* on|off Signed-off-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com> Message-Id: <1493054398-26013-1-git-send-email-joserz@linux.vnet.ibm.com> Reviewed-by: Fam Zheng <famz@redhat.com> [Also handle trylock, cond_wait and win32; trace "unlocked" while still in the critical section, so that "unlocked" always comes before the next "locked" tracepoint. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-27win32: replace custom mutex and condition variable with native primitivesAndrey Shedel
The multithreaded TCG implementation exposed deadlocks in the win32 condition variables: as implemented, qemu_cond_broadcast waited on receivers, whereas the pthreads API it was intended to emulate does not. This was causing a deadlock because broadcast was called while holding the IO lock, as well as all possible waiters blocked on the same lock. This patch replaces all the custom synchronisation code for mutexes and condition variables with native Windows primitives (SRWlocks and condition variables) with the same semantics as their POSIX equivalents. To enable that, it requires a Windows Vista or newer host OS. Signed-off-by: Andrey Shedel <ashedel@microsoft.com> [AB: edited commit message] Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com> Message-Id: <20170324220141.10104-1-Andrew.Baumann@microsoft.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-20Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell
* QOM interface fix (Eduardo) * RTC fixes (Gaohuai, Igor) * Memory leak fixes (Li Qiang, me) * Ctrl-a b regression (Marc-André) * Stubs cleanups and fixes (Leif, me) * hxtool tweak (me) * HAX support (Vincent) * QemuThread, exec.c and SCSI fixes (Roman, Xinhua, me) * PC_COMPAT_2_8 fix (Marcelo) * stronger bitmap assertions (Peter) # gpg: Signature made Fri 20 Jan 2017 12:49:01 GMT # gpg: using RSA key 0xBFFBD25F78C7AE83 # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * remotes/bonzini/tags/for-upstream: (35 commits) pc.h: move x-mach-use-reliable-get-clock compat entry to PC_COMPAT_2_8 bitmap: assert that start and nr are non negative Revert "win32: don't run subprocess tests on Mingw32 platform" hax: add Darwin support Plumb the HAXM-based hardware acceleration support target/i386: Add Intel HAX files kvm: move cpu synchronization code KVM: PPC: eliminate unnecessary duplicate constants ramblock-notifier: new char: fix ctrl-a b not working exec: Add missing rcu_read_unlock x86: ioapic: fix fail migration when irqchip=split x86: ioapic: dump version for "info ioapic" x86: ioapic: add traces for ioapic hxtool: emit Texinfo headings as @subsection qemu-thread: fix qemu_thread_set_name() race in qemu_thread_create() serial: fix memory leak in serial exit scsi-block: fix direction of BYTCHK test for VERIFY commands pc: fix crash in rtc_set_memory() if initial cpu is marked as hotplugged acpi: filter based on CONFIG_ACPI_X86 rather than TARGET ... # Conflicts: # include/hw/i386/pc.h
2017-01-19Plumb the HAXM-based hardware acceleration supportVincent Palatin
Use the Intel HAX is kernel-based hardware acceleration module for Windows (similar to KVM on Linux). Based on the "target/i386: Add Intel HAX to android emulator" patch from David Chou <david.j.chou@intel.com> Signed-off-by: Vincent Palatin <vpalatin@chromium.org> Message-Id: <7b9cae28a0c379ab459c7a8545c9a39762bd394f.1484045952.git.vpalatin@chromium.org> [Drop hax_populate_ram stub. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-16qemu-thread: optimize QemuLockCnt with futexes on LinuxPaolo Bonzini
This is complex, but I think it is reasonably documented in the source. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170112180800.21085-5-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-28qemu-thread: introduce QemuRecMutexPaolo Bonzini
GRecMutex is new in glib 2.32, so we cannot use it. Introduce a recursive mutex in qemu-thread instead, which will be used instead of RFifoLock. Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1477565348-5458-20-git-send-email-pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com>
2016-10-24qemu-thread: use acquire/release to clarify semantics of QemuEventPaolo Bonzini
Do not use the somewhat mysterious atomic_mb_read/atomic_mb_set, instead make sure that the operations on QemuEvent are annotated with the desired acquire and release semantics. In particular, qemu_event_set wakes up the waiting thread, so it must be a release from the POV of the waker (compare with qemu_mutex_unlock). And it actually needs a full barrier, because that's the only thing that provides something like a "load-release". Use smp_mb_acquire until we have atomic_load_acquire and atomic_store_release in atomic.h. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-04util: Clean up includesPeter Maydell
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1454089805-5470-6-git-send-email-peter.maydell@linaro.org
2015-09-24qemu-thread: add a fast path to the Win32 QemuEventPaolo Bonzini
QemuEvents are used heavily by call_rcu. We do not want them to be slow, but the current implementation does a kernel call on every invocation of qemu_event_* and won't cut it. So, wrap a Win32 manual-reset event with a fast userspace path. The states and transitions are the same as for the futex and mutex/condvar implementations, but the slow path is different of course. The idea is to reset the Win32 event lazily, as part of a test-reset-test-wait sequence. Such a sequence is, indeed, how QemuEvents are used by RCU and other subsystems! The patch includes a formal model of the algorithm. Tested-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Weil <sw@weilnetz.de>
2015-01-13qemu-thread: add per-thread atexit functionsPaolo Bonzini
Destructors are the main additional feature of pthread TLS compared to __thread. If we were using C++ (hint, hint!) we could have used thread-local objects with a destructor. Since we are not, instead, we add a simple Notifier-based API. Note that the notifier must be per-thread as well. We can add a global list as well later, perhaps. The Win32 implementation has some complications because a) detached threads used not to have a QemuThreadData; b) the main thread does not go through win32_start_routine, so we have to use atexit too. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1417518350-6167-3-git-send-email-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-27Detect pthread_setname_np at configure timeDr. David Alan Gilbert
Warn if no way of setting thread name is available. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-03-09Add a 'name' parameter to qemu_thread_createDr. David Alan Gilbert
If enabled, set the thread name at creation (on GNU systems with pthread_set_np) Fix up all the callers with a thread name Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2014-03-09Add 'debug-threads' suboption to --nameDr. David Alan Gilbert
Add flag storage to qemu-thread-* to store the namethreads flag Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2013-10-17qemu-thread: add QemuEventPaolo Bonzini
This emulates Win32 manual-reset events using futexes or conditional variables. Typical ways to use them are with multi-producer, single-consumer data structures, to test for a complex condition whose elements come from different threads: for (;;) { qemu_event_reset(ev); ... test complex condition ... if (condition is true) { break; } qemu_event_wait(ev); } Or more efficiently (but with some duplication): ... evaluate condition ... while (!condition) { qemu_event_reset(ev); ... evaluate condition ... if (!condition) { qemu_event_wait(ev); ... evaluate condition ... } } QemuEvent provides a very fast userspace path in the common case when no other thread is waiting, or the event is not changing state. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-01-12build: move libqemuutil.a components to util/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>