From: KONRAD Frederic <fred.kon...@greensocs.com> This protects queued_work_* used by async_run_on_cpu, run_on_cpu and flush_queued_work with a new lock (work_mutex) to prevent multiple (concurrent) access.
Signed-off-by: KONRAD Frederic <fred.kon...@greensocs.com> Reviewed-by: Alex Bennée <alex.ben...@linaro.org> Changes V1 -> V2: * Unlock the mutex while running the callback. --- cpus.c | 11 +++++++++++ include/qom/cpu.h | 3 +++ qom/cpu.c | 1 + 3 files changed, 15 insertions(+) diff --git a/cpus.c b/cpus.c index b00a423..eabd4b1 100644 --- a/cpus.c +++ b/cpus.c @@ -845,6 +845,8 @@ void run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data) wi.func = func; wi.data = data; wi.free = false; + + qemu_mutex_lock(&cpu->work_mutex); if (cpu->queued_work_first == NULL) { cpu->queued_work_first = &wi; } else { @@ -853,6 +855,7 @@ void run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data) cpu->queued_work_last = &wi; wi.next = NULL; wi.done = false; + qemu_mutex_unlock(&cpu->work_mutex); qemu_cpu_kick(cpu); while (!wi.done) { @@ -876,6 +879,8 @@ void async_run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data) wi->func = func; wi->data = data; wi->free = true; + + qemu_mutex_lock(&cpu->work_mutex); if (cpu->queued_work_first == NULL) { cpu->queued_work_first = wi; } else { @@ -884,6 +889,7 @@ void async_run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data) cpu->queued_work_last = wi; wi->next = NULL; wi->done = false; + qemu_mutex_unlock(&cpu->work_mutex); qemu_cpu_kick(cpu); } @@ -896,15 +902,20 @@ static void flush_queued_work(CPUState *cpu) return; } + qemu_mutex_lock(&cpu->work_mutex); while ((wi = cpu->queued_work_first)) { cpu->queued_work_first = wi->next; + qemu_mutex_unlock(&cpu->work_mutex); wi->func(wi->data); + qemu_mutex_lock(&cpu->work_mutex); wi->done = true; if (wi->free) { g_free(wi); } } cpu->queued_work_last = NULL; + qemu_mutex_unlock(&cpu->work_mutex); + qemu_cond_broadcast(&qemu_work_cond); } diff --git a/include/qom/cpu.h b/include/qom/cpu.h index 20aabc9..efa9624 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -242,6 +242,8 @@ struct kvm_run; * @mem_io_pc: Host Program Counter at which the memory was accessed. * @mem_io_vaddr: Target virtual address at which the memory was accessed. * @kvm_fd: vCPU file descriptor for KVM. + * @work_mutex: Lock to prevent multiple access to queued_work_*. + * @queued_work_first: First asynchronous work pending. * * State of one CPU core or thread. */ @@ -262,6 +264,7 @@ struct CPUState { uint32_t host_tid; bool running; struct QemuCond *halt_cond; + QemuMutex work_mutex; struct qemu_work_item *queued_work_first, *queued_work_last; bool thread_kicked; bool created; diff --git a/qom/cpu.c b/qom/cpu.c index eb9cfec..4e12598 100644 --- a/qom/cpu.c +++ b/qom/cpu.c @@ -316,6 +316,7 @@ static void cpu_common_initfn(Object *obj) cpu->gdb_num_regs = cpu->gdb_num_g_regs = cc->gdb_num_core_regs; QTAILQ_INIT(&cpu->breakpoints); QTAILQ_INIT(&cpu->watchpoints); + qemu_mutex_init(&cpu->work_mutex); } static void cpu_common_finalize(Object *obj) -- 1.9.0