Commit Graph

14 Commits

Author SHA1 Message Date
Peter Maydell
aafd758410 util: Clean up includes
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
2016-02-04 17:01:04 +00:00
Peter Maydell
a2aa09e181 * Support for jemalloc
* qemu_mutex_lock_iothread "No such process" fix
 * cutils: qemu_strto* wrappers
 * iohandler.c simplification
 * Many other fixes and misc patches.
 
 And some MTTCG work (with Emilio's fixes squashed):
 * Signal-free TCG kick
 * Removing spinlock in favor of QemuMutex
 * User-mode emulation multi-threading fixes/docs
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* Support for jemalloc
* qemu_mutex_lock_iothread "No such process" fix
* cutils: qemu_strto* wrappers
* iohandler.c simplification
* Many other fixes and misc patches.

And some MTTCG work (with Emilio's fixes squashed):
* Signal-free TCG kick
* Removing spinlock in favor of QemuMutex
* User-mode emulation multi-threading fixes/docs

# gpg: Signature made Thu 10 Sep 2015 09:03:07 BST using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"

* remotes/bonzini/tags/for-upstream: (44 commits)
  cutils: work around platform differences in strto{l,ul,ll,ull}
  cpu-exec: fix lock hierarchy for user-mode emulation
  exec: make mmap_lock/mmap_unlock globally available
  tcg: comment on which functions have to be called with mmap_lock held
  tcg: add memory barriers in page_find_alloc accesses
  remove unused spinlock.
  replace spinlock by QemuMutex.
  cpus: remove tcg_halt_cond and tcg_cpu_thread globals
  cpus: protect work list with work_mutex
  scripts/dump-guest-memory.py: fix after RAMBlock change
  configure: Add support for jemalloc
  add macro file for coccinelle
  configure: factor out adding disas configure
  vhost-scsi: fix wrong vhost-scsi firmware path
  checkpatch: remove tests that are not relevant outside the kernel
  checkpatch: adapt some tests to QEMU
  CODING_STYLE: update mixed declaration rules
  qmp: Add example usage of strto*l() qemu wrapper
  cutils: Add qemu_strtoull() wrapper
  cutils: Add qemu_strtoll() wrapper
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-09-14 16:13:16 +01:00
Veres Lajos
67cc32ebfd typofixes - v4
Signed-off-by: Veres Lajos <vlajos@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:45:43 +03:00
Emilio G. Cota
16ef9d0252 qemu-thread: handle spurious futex_wait wakeups
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1440375847-17603-12-git-send-email-cota@braap.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-02 23:03:03 +02:00
Paolo Bonzini
24fa90499f qemu-thread: do not use PTHREAD_MUTEX_ERRORCHECK
PTHREAD_MUTEX_ERRORCHECK is completely broken with respect to fork.
The way to safely do fork is to bring all threads to a quiescent
state by acquiring locks (either in callers---as we do for the
iothread mutex---or using pthread_atfork's prepare callbacks)
and then release them in the child.

The problem is that releasing error-checking locks in the child
fails under glibc with EPERM, because the mutex stores a different
owner tid than the duplicated thread in the child process.  We
could make it work for locks acquired via pthread_atfork, by
recreating the mutex in the child instead of unlocking it
(we know that there are no other threads that could have taken
the mutex; but when the lock is acquired in fork's caller
that would not be possible.

The simplest solution is just to forgo error checking.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-10 10:49:25 +01:00
Paolo Bonzini
158ef8cbb7 qemu-thread: fix qemu_event without futexes
This had a possible deadlock that was visible with rcutorture.

    qemu_event_set                    qemu_event_wait
    ----------------------------------------------------------------
                                      cmpxchg reads FREE, writes BUSY
                                      futex_wait: pthread_mutex_lock
                                      futex_wait: value == BUSY
    xchg reads BUSY, writes SET
    futex_wake: pthread_cond_broadcast
                                      futex_wait: pthread_cond_wait
                                      <deadlock>

The fix is simply to avoid condvar tricks and do the obvious locking
around pthread_cond_broadcast:

    qemu_event_set        qemu_event_wait
    ----------------------------------------------------------------
                                      cmpxchg reads FREE, writes BUSY
                                      futex_wait: pthread_mutex_lock
                                      futex_wait: value == BUSY
    xchg reads BUSY, writes SET
    futex_wake: pthread_mutex_lock
    (blocks)
                                      futex_wait: pthread_cond_wait
    (mutex unlocked)
    futex_wake: pthread_cond_broadcast
    futex_wake: pthread_mutex_unlock
                                      futex_wait: pthread_mutex_unlock

Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-02 16:55:09 +01:00
Paolo Bonzini
ef57137f1b qemu-thread: add per-thread atexit functions
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>
2015-01-13 13:43:29 +00:00
Dr. David Alan Gilbert
5c31207941 Detect pthread_setname_np at configure time
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>
2014-03-27 17:48:11 +02:00
Jan Kiszka
01207d0b78 qemu-thread-posix: Fix build against older glibc version
pthread_setname_np was introduced with 2.12.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-03-11 18:19:21 +00:00
Dr. David Alan Gilbert
4900116e6f Add a 'name' parameter to qemu_thread_create
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>
2014-03-09 21:09:38 +02:00
Dr. David Alan Gilbert
8f480de0c9 Add 'debug-threads' suboption to --name
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>
2014-03-09 21:09:37 +02:00
Paolo Bonzini
c7c4d063f5 qemu-thread: add QemuEvent
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>
2013-10-17 17:30:55 +02:00
Izumi Tsutsui
79761c6681 semaphore: fix a hangup problem under load on NetBSD hosts.
Fix following bugs in "fallback implementation of counting semaphores
with mutex+condvar" added in c166cb72f1:
 - waiting threads are not restarted properly if more than one threads
   are waiting unblock signals in qemu_sem_timedwait()
 - possible missing pthread_cond_signal(3) calls when waiting threads
   are returned by ETIMEDOUT
 - fix an uninitialized variable
The problem is analyzed by and fix is provided by Noriyuki Soda.

Also put additional cleanup suggested by Laszlo Ersek:
 - make QemuSemaphore.count unsigned (it won't be negative)
 - check a return value of in pthread_cond_wait() in qemu_sem_wait()

Signed-off-by: Izumi Tsutsui <tsutsui@ceres.dti.ne.jp>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1372841894-10634-1-git-send-email-tsutsui@ceres.dti.ne.jp
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-08-05 11:48:00 -05:00
Paolo Bonzini
baacf04799 build: move libqemuutil.a components to util/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-01-12 18:42:50 +01:00