comments below
On 01/30/14 11:20, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
>
> 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 <dgilb...@redhat.com>
> ---
> cpus.c | 25 ++++++++++++++++++++-----
> hw/block/dataplane/virtio-blk.c | 2 +-
> hw/usb/ccid-card-emulated.c | 8 ++++----
> include/qemu/thread.h | 2 +-
> libcacard/vscclient.c | 2 +-
> migration.c | 2 +-
> thread-pool.c | 2 +-
> ui/vnc-jobs.c | 3 ++-
> util/compatfd.c | 3 ++-
> util/qemu-thread-posix.c | 9 +++++++--
> util/qemu-thread-win32.c | 2 +-
> 11 files changed, 41 insertions(+), 19 deletions(-)
>
> diff --git a/cpus.c b/cpus.c
> index ca4c59f..e5bb271 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -1117,16 +1117,23 @@ void resume_all_vcpus(void)
> }
> }
>
> +/* For temporary buffers for forming a name */
> +#define TMP_THREAD_NAME_LEN 16
This should be called _SIZE in my opinion, because it seems to include
the trailing NUL character.
Alternatively, as much as I hate glib's presence in qemu, you could
replace each (fixed size buffer, snprintf()) pair with a (pointer,
g_strdup_printf(), g_free()) triplet.
> +
> static void qemu_tcg_init_vcpu(CPUState *cpu)
> {
> + char thread_name[TMP_THREAD_NAME_LEN];
> +
> /* share a single thread for all cpus with TCG */
> if (!tcg_cpu_thread) {
> cpu->thread = g_malloc0(sizeof(QemuThread));
> cpu->halt_cond = g_malloc0(sizeof(QemuCond));
> qemu_cond_init(cpu->halt_cond);
> tcg_halt_cond = cpu->halt_cond;
> - qemu_thread_create(cpu->thread, qemu_tcg_cpu_thread_fn, cpu,
> - QEMU_THREAD_JOINABLE);
> + snprintf(thread_name, TMP_THREAD_NAME_LEN, "CPU %d/TCG",
> + cpu->cpu_index);
> + qemu_thread_create(cpu->thread, thread_name, qemu_tcg_cpu_thread_fn,
> + cpu, QEMU_THREAD_JOINABLE);
> #ifdef _WIN32
> cpu->hThread = qemu_thread_get_handle(cpu->thread);
> #endif
> @@ -1142,11 +1149,15 @@ static void qemu_tcg_init_vcpu(CPUState *cpu)
>
> static void qemu_kvm_start_vcpu(CPUState *cpu)
> {
> + char thread_name[TMP_THREAD_NAME_LEN];
> +
> cpu->thread = g_malloc0(sizeof(QemuThread));
> cpu->halt_cond = g_malloc0(sizeof(QemuCond));
> qemu_cond_init(cpu->halt_cond);
> - qemu_thread_create(cpu->thread, qemu_kvm_cpu_thread_fn, cpu,
> - QEMU_THREAD_JOINABLE);
> + snprintf(thread_name, TMP_THREAD_NAME_LEN, "CPU %d/KVM",
> + cpu->cpu_index);
> + qemu_thread_create(cpu->thread, thread_name, qemu_kvm_cpu_thread_fn,
> + cpu, QEMU_THREAD_JOINABLE);
> while (!cpu->created) {
> qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex);
> }
> @@ -1154,10 +1165,14 @@ static void qemu_kvm_start_vcpu(CPUState *cpu)
>
> static void qemu_dummy_start_vcpu(CPUState *cpu)
> {
> + char thread_name[TMP_THREAD_NAME_LEN];
> +
> cpu->thread = g_malloc0(sizeof(QemuThread));
> cpu->halt_cond = g_malloc0(sizeof(QemuCond));
> qemu_cond_init(cpu->halt_cond);
> - qemu_thread_create(cpu->thread, qemu_dummy_cpu_thread_fn, cpu,
> + snprintf(thread_name, TMP_THREAD_NAME_LEN, "CPU %d/DUMMY",
> + cpu->cpu_index);
> + qemu_thread_create(cpu->thread, thread_name, qemu_dummy_cpu_thread_fn,
> cpu,
> QEMU_THREAD_JOINABLE);
> while (!cpu->created) {
> qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex);
> diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
> index 456d437..980a684 100644
> --- a/hw/block/dataplane/virtio-blk.c
> +++ b/hw/block/dataplane/virtio-blk.c
> @@ -358,7 +358,7 @@ static void start_data_plane_bh(void *opaque)
>
> qemu_bh_delete(s->start_bh);
> s->start_bh = NULL;
> - qemu_thread_create(&s->thread, data_plane_thread,
> + qemu_thread_create(&s->thread, "data_plane", data_plane_thread,
> s, QEMU_THREAD_JOINABLE);
> }
Don't really want to suggest feature creep, but since we can have
several dataplane threads as well, I suggest appending the serial number
of the virtio-blk device, s->blk->serial (can be NULL). Example for
access is in do_get_id_cmd(). Of course with this free-form string,
g_strdup_printf() becomes more attractive.
>
> diff --git a/hw/usb/ccid-card-emulated.c b/hw/usb/ccid-card-emulated.c
> index aa913df..7213c89 100644
> --- a/hw/usb/ccid-card-emulated.c
> +++ b/hw/usb/ccid-card-emulated.c
> @@ -546,10 +546,10 @@ static int emulated_initfn(CCIDCardState *base)
> printf("%s: failed to initialize vcard\n", EMULATED_DEV_NAME);
> return -1;
> }
> - qemu_thread_create(&card->event_thread_id, event_thread, card,
> - QEMU_THREAD_JOINABLE);
> - qemu_thread_create(&card->apdu_thread_id, handle_apdu_thread, card,
> - QEMU_THREAD_JOINABLE);
> + qemu_thread_create(&card->event_thread_id, "ccid/event", event_thread,
> + card, QEMU_THREAD_JOINABLE);
> + qemu_thread_create(&card->apdu_thread_id, "ccid/apdu",
> handle_apdu_thread,
> + card, QEMU_THREAD_JOINABLE);
> return 0;
> }
No clue how many there can be of these.
>
> diff --git a/include/qemu/thread.h b/include/qemu/thread.h
> index bf1e110..f7e3b9b 100644
> --- a/include/qemu/thread.h
> +++ b/include/qemu/thread.h
> @@ -52,7 +52,7 @@ void qemu_event_reset(QemuEvent *ev);
> void qemu_event_wait(QemuEvent *ev);
> void qemu_event_destroy(QemuEvent *ev);
>
> -void qemu_thread_create(QemuThread *thread,
> +void qemu_thread_create(QemuThread *thread, const char *name,
> void *(*start_routine)(void *),
> void *arg, int mode);
> void *qemu_thread_join(QemuThread *thread);
> diff --git a/libcacard/vscclient.c b/libcacard/vscclient.c
> index 24f7088..3477ab3 100644
> --- a/libcacard/vscclient.c
> +++ b/libcacard/vscclient.c
> @@ -269,7 +269,7 @@ on_host_init(VSCMsgHeader *mhHeader, VSCMsgInit *incoming)
> send_msg(VSC_ReaderRemove, VSCARD_MINIMAL_READER_ID, NULL, 0);
> /* launch the event_thread. This will trigger reader adds for all the
> * existing readers */
> - qemu_thread_create(&thread_id, event_thread, NULL, 0);
> + qemu_thread_create(&thread_id, "vsc/event", event_thread, NULL, 0);
> return 0;
> }
Ditto.
>
> diff --git a/migration.c b/migration.c
> index 7235c23..bddec7e 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -679,6 +679,6 @@ void migrate_fd_connect(MigrationState *s)
> /* Notify before starting migration thread */
> notifier_list_notify(&migration_state_notifiers, s);
>
> - qemu_thread_create(&s->thread, migration_thread, s,
> + qemu_thread_create(&s->thread, "migration", migration_thread, s,
> QEMU_THREAD_JOINABLE);
> }
At most one such thread at a time, right?
> diff --git a/thread-pool.c b/thread-pool.c
> index 3735fd3..fbdd3ff 100644
> --- a/thread-pool.c
> +++ b/thread-pool.c
> @@ -140,7 +140,7 @@ static void do_spawn_thread(ThreadPool *pool)
> pool->new_threads--;
> pool->pending_threads++;
>
> - qemu_thread_create(&t, worker_thread, pool, QEMU_THREAD_DETACHED);
> + qemu_thread_create(&t, "worker", worker_thread, pool,
> QEMU_THREAD_DETACHED);
> }
I do think these guys should be numbered somehow. "pending_threads"
looks like an obvious choice, but it might be incorrect.
>
> static void spawn_thread_bh_fn(void *opaque)
> diff --git a/ui/vnc-jobs.c b/ui/vnc-jobs.c
> index 2d3fce8..3f3c47b 100644
> --- a/ui/vnc-jobs.c
> +++ b/ui/vnc-jobs.c
> @@ -333,7 +333,8 @@ void vnc_start_worker_thread(void)
> return ;
>
> q = vnc_queue_init();
> - qemu_thread_create(&q->thread, vnc_worker_thread, q,
> QEMU_THREAD_DETACHED);
> + qemu_thread_create(&q->thread, "vnc_worker", vnc_worker_thread, q,
> + QEMU_THREAD_DETACHED);
> queue = q; /* Set global queue */
> }
Probably one thread only.
>
> diff --git a/util/compatfd.c b/util/compatfd.c
> index 430a41c..341ada6 100644
> --- a/util/compatfd.c
> +++ b/util/compatfd.c
> @@ -88,7 +88,8 @@ static int qemu_signalfd_compat(const sigset_t *mask)
> memcpy(&info->mask, mask, sizeof(*mask));
> info->fd = fds[1];
>
> - qemu_thread_create(&thread, sigwait_compat, info, QEMU_THREAD_DETACHED);
> + qemu_thread_create(&thread, "signalfd_compat", sigwait_compat, info,
> + QEMU_THREAD_DETACHED);
>
> return fds[0];
> }
Ditto.
> diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
> index 0fa6c81..45113b4 100644
> --- a/util/qemu-thread-posix.c
> +++ b/util/qemu-thread-posix.c
> @@ -394,8 +394,7 @@ void qemu_event_wait(QemuEvent *ev)
> }
> }
>
> -
> -void qemu_thread_create(QemuThread *thread,
> +void qemu_thread_create(QemuThread *thread, const char *name,
> void *(*start_routine)(void*),
> void *arg, int mode)
> {
> @@ -421,6 +420,12 @@ void qemu_thread_create(QemuThread *thread,
> if (err)
> error_exit(err, __func__);
>
> +#ifdef _GNU_SOURCE
> + if (name_threads) {
> + pthread_setname_np(thread->thread, name);
> + }
> +#endif
> +
Maybe a retval check? Or do we ignore ERANGE on purpose?
> pthread_sigmask(SIG_SETMASK, &oldset, NULL);
>
> pthread_attr_destroy(&attr);
> diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c
> index e42cb77..b9c957b 100644
> --- a/util/qemu-thread-win32.c
> +++ b/util/qemu-thread-win32.c
> @@ -333,7 +333,7 @@ void *qemu_thread_join(QemuThread *thread)
> return ret;
> }
>
> -void qemu_thread_create(QemuThread *thread,
> +void qemu_thread_create(QemuThread *thread, const char *name,
> void *(*start_routine)(void *),
> void *arg, int mode)
> {
>
Anyway this is for helping debugging, and there's nothing in here that
I'd call a bug, so I won't waste your time with asking for a new version. :)
Reviewed-by: Laszlo Ersek <ler...@redhat.com>
Thanks!
Laszlo
