I tried to use it, but it would then create a deadlock at a very early
stage of the stress test.
The problem is likely related to the fact that flush_queued_work
happens with the global mutex locked.
As Frederick suggested, we can use the newly introduced
flush_queued_safe_work for this.
Regards,
alvise
On Fri, Jul 10, 2015 at 11:36 AM, Paolo Bonzini <pbonz...@redhat.com> wrote:
>
>
> On 10/07/2015 10:23, Alvise Rigo wrote:
>> In order to perfom "lazy" TLB invalidation requests, introduce a
>> queue of callbacks at every vCPU disposal that will be fired just
>> before entering the next TB.
>>
>> Suggested-by: Jani Kokkonen <jani.kokko...@huawei.com>
>> Suggested-by: Claudio Fontana <claudio.font...@huawei.com>
>> Signed-off-by: Alvise Rigo <a.r...@virtualopensystems.com>
>
> Why is async_run_on_cpu not enough?
>
> Paolo
>
>> ---
>> cpus.c | 34 ++++++++++++++++++++++++++++++++++
>> exec.c | 1 +
>> include/qom/cpu.h | 20 ++++++++++++++++++++
>> 3 files changed, 55 insertions(+)
>>
>> diff --git a/cpus.c b/cpus.c
>> index f4d938e..b9f0329 100644
>> --- a/cpus.c
>> +++ b/cpus.c
>> @@ -1421,6 +1421,7 @@ static int tcg_cpu_exec(CPUArchState *env)
>> cpu->icount_extra = count;
>> }
>> qemu_mutex_unlock_iothread();
>> + cpu_exit_callbacks_call_all(cpu);
>> ret = cpu_exec(env);
>> cpu->tcg_executing = 0;
>>
>> @@ -1469,6 +1470,39 @@ static void tcg_exec_all(CPUState *cpu)
>> cpu->exit_request = 0;
>> }
>>
>> +void cpu_exit_callback_add(CPUState *cpu, CPUExitCallback callback,
>> + void *opaque)
>> +{
>> + CPUExitCB *cb;
>> +
>> + cb = g_malloc(sizeof(*cb));
>> + cb->callback = callback;
>> + cb->opaque = opaque;
>> +
>> + qemu_mutex_lock(&cpu->exit_cbs.mutex);
>> + QTAILQ_INSERT_TAIL(&cpu->exit_cbs.exit_callbacks, cb, entry);
>> + qemu_mutex_unlock(&cpu->exit_cbs.mutex);
>> +}
>> +
>> +void cpu_exit_callbacks_call_all(CPUState *cpu)
>> +{
>> + CPUExitCB *cb, *next;
>> +
>> + if (QTAILQ_EMPTY(&cpu->exit_cbs.exit_callbacks)) {
>> + return;
>> + }
>> +
>> + QTAILQ_FOREACH_SAFE(cb, &cpu->exit_cbs.exit_callbacks, entry, next) {
>> + cb->callback(cpu, cb->opaque);
>> +
>> + /* one-shot callbacks, remove it after using it */
>> + qemu_mutex_lock(&cpu->exit_cbs.mutex);
>> + QTAILQ_REMOVE(&cpu->exit_cbs.exit_callbacks, cb, entry);
>> + g_free(cb);
>> + qemu_mutex_unlock(&cpu->exit_cbs.mutex);
>> + }
>> +}
>> +
>> void list_cpus(FILE *f, fprintf_function cpu_fprintf, const char *optarg)
>> {
>> /* XXX: implement xxx_cpu_list for targets that still miss it */
>> diff --git a/exec.c b/exec.c
>> index 51958ed..322f2c6 100644
>> --- a/exec.c
>> +++ b/exec.c
>> @@ -531,6 +531,7 @@ void cpu_exec_init(CPUArchState *env)
>> cpu->numa_node = 0;
>> QTAILQ_INIT(&cpu->breakpoints);
>> QTAILQ_INIT(&cpu->watchpoints);
>> + QTAILQ_INIT(&cpu->exit_cbs.exit_callbacks);
>> #ifndef CONFIG_USER_ONLY
>> cpu->as = &address_space_memory;
>> cpu->thread_id = qemu_get_thread_id();
>> diff --git a/include/qom/cpu.h b/include/qom/cpu.h
>> index 8d121b3..0ec020b 100644
>> --- a/include/qom/cpu.h
>> +++ b/include/qom/cpu.h
>> @@ -201,6 +201,24 @@ typedef struct CPUWatchpoint {
>> QTAILQ_ENTRY(CPUWatchpoint) entry;
>> } CPUWatchpoint;
>>
>> +/* vCPU exit callbacks */
>> +typedef void (*CPUExitCallback)(CPUState *cpu, void *opaque);
>> +struct CPUExitCBs {
>> + QemuMutex mutex;
>> + QTAILQ_HEAD(exit_callbacks_head, CPUExitCB) exit_callbacks;
>> +};
>> +
>> +typedef struct CPUExitCB {
>> + CPUExitCallback callback;
>> + void *opaque;
>> +
>> + QTAILQ_ENTRY(CPUExitCB) entry;
>> +} CPUExitCB;
>> +
>> +void cpu_exit_callback_add(CPUState *cpu, CPUExitCallback callback,
>> + void *opaque);
>> +void cpu_exit_callbacks_call_all(CPUState *cpu);
>> +
>> /* Rendezvous support */
>> #define TCG_RDV_POLLING_PERIOD 10
>> typedef struct CpuExitRendezvous {
>> @@ -305,6 +323,8 @@ struct CPUState {
>>
>> void *opaque;
>>
>> + /* One-shot callbacks for stopping requests. */
>> + struct CPUExitCBs exit_cbs;
>> volatile int pending_rdv;
>>
>> /* In order to avoid passing too many arguments to the MMIO helpers,
>>
