On Thu, Aug 06, 2015 at 10:57:07AM +0530, Bharata B Rao wrote: > CPUState *cpu gets added to the cpus list during cpu_exec_init(). It > should be removed from cpu_exec_exit(). > > cpu_exec_init() is called from generic CPU::instance_finalize and some > archs like PowerPC call it from CPU unrealizefn. So ensure that we > dequeue the cpu only once. > > Instead of introducing a new field CPUState.queued, I could have used > CPUState.cpu_index to check if the cpu is already dequeued from the list. > Since that doesn't work for CONFIG_USER_ONLY, I had to add a new field. > > Signed-off-by: Bharata B Rao <bhar...@linux.vnet.ibm.com>
This seems reasonable to me, but I'm wondering how x86 cpu hotplug /
unplug is working without it.
> ---
> exec.c | 11 +++++++++++
> include/qom/cpu.h | 1 +
> 2 files changed, 12 insertions(+)
>
> diff --git a/exec.c b/exec.c
> index 0a4a0c5..b196d68 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -550,6 +550,10 @@ void cpu_exec_exit(CPUState *cpu)
> return;
> }
>
> + if (cpu->queued) {
> + QTAILQ_REMOVE(&cpus, cpu, node);
> + cpu->queued = false;
> + }
> bitmap_clear(cpu_index_map, cpu->cpu_index, 1);
> cpu->cpu_index = -1;
> }
> @@ -568,6 +572,12 @@ static int cpu_get_free_index(Error **errp)
>
> void cpu_exec_exit(CPUState *cpu)
> {
> + cpu_list_lock();
> + if (cpu->queued) {
> + QTAILQ_REMOVE(&cpus, cpu, node);
> + cpu->queued = false;
> + }
> + cpu_list_unlock();
> }
> #endif
>
> @@ -595,6 +605,7 @@ void cpu_exec_init(CPUState *cpu, Error **errp)
> return;
> }
> QTAILQ_INSERT_TAIL(&cpus, cpu, node);
> + cpu->queued = true;
> #if defined(CONFIG_USER_ONLY)
> cpu_list_unlock();
> #endif
> diff --git a/include/qom/cpu.h b/include/qom/cpu.h
> index 20aabc9..a00e3a8 100644
> --- a/include/qom/cpu.h
> +++ b/include/qom/cpu.h
> @@ -284,6 +284,7 @@ struct CPUState {
> int gdb_num_regs;
> int gdb_num_g_regs;
> QTAILQ_ENTRY(CPUState) node;
> + bool queued;
>
> /* ice debug support */
> QTAILQ_HEAD(breakpoints_head, CPUBreakpoint) breakpoints;
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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