| Message ID | 1453960195-15181-3-git-send-email-bharata@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Jan 28, 2016 at 11:19:44AM +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. > > Now -1 value for cpu->cpu_index indicates that we have already dequeued > the cpu for CONFIG_USER_ONLY case also. > > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> > Reviewed-by: David Gibson <david@gibson.dropbear.id.au> > --- > exec.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/exec.c b/exec.c > index 7115403..c8da9d4 100644 > --- a/exec.c > +++ b/exec.c > @@ -596,6 +596,7 @@ void cpu_exec_exit(CPUState *cpu) > return; > } > > + QTAILQ_REMOVE(&cpus, cpu, node); > bitmap_clear(cpu_index_map, cpu->cpu_index, 1); > cpu->cpu_index = -1; > } > @@ -614,6 +615,15 @@ static int cpu_get_free_index(Error **errp) > > void cpu_exec_exit(CPUState *cpu) > { > + cpu_list_lock(); > + if (cpu->cpu_index == -1) { > + cpu_list_unlock(); > + return; > + } > + > + QTAILQ_REMOVE(&cpus, cpu, node); > + cpu->cpu_index = -1; > + cpu_list_unlock(); With this, the only differences between the two cpu_exec_exit() implementations are: * cpu_list_lock()/cpu_list_unlock() functions. * We can add !CONFIG_USER_ONLY stubs for them. * The bitmap_clear() call. * It can be abstracted away in a cpu_release_index() function, just like we already have a CONFIG_USER_ONLY version of cpu_get_free_index(). * I was going to suggest using cpu_index_map on CONFIG_USER_ONLY too, but I assume we don't want to limit the number of threads in *-user to MAX_CPUMASK_BITS. This way we won't need to duplicate cpu_exec_exit() code.
On Thu, Jan 28, 2016 at 05:19:33PM -0200, Eduardo Habkost wrote: > On Thu, Jan 28, 2016 at 11:19:44AM +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. > > > > Now -1 value for cpu->cpu_index indicates that we have already dequeued > > the cpu for CONFIG_USER_ONLY case also. > > > > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> > > Reviewed-by: David Gibson <david@gibson.dropbear.id.au> > > --- > > exec.c | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > diff --git a/exec.c b/exec.c > > index 7115403..c8da9d4 100644 > > --- a/exec.c > > +++ b/exec.c > > @@ -596,6 +596,7 @@ void cpu_exec_exit(CPUState *cpu) > > return; > > } > > > > + QTAILQ_REMOVE(&cpus, cpu, node); > > bitmap_clear(cpu_index_map, cpu->cpu_index, 1); > > cpu->cpu_index = -1; > > } > > @@ -614,6 +615,15 @@ static int cpu_get_free_index(Error **errp) > > > > void cpu_exec_exit(CPUState *cpu) > > { > > + cpu_list_lock(); > > + if (cpu->cpu_index == -1) { > > + cpu_list_unlock(); > > + return; > > + } > > + > > + QTAILQ_REMOVE(&cpus, cpu, node); > > + cpu->cpu_index = -1; > > + cpu_list_unlock(); > > With this, the only differences between the two cpu_exec_exit() > implementations are: > > * cpu_list_lock()/cpu_list_unlock() functions. > * We can add !CONFIG_USER_ONLY stubs for them. > * The bitmap_clear() call. > * It can be abstracted away in a cpu_release_index() function, > just like we already have a CONFIG_USER_ONLY version of > cpu_get_free_index(). Ok, made those changes so that cpu_exec_exit() will be a common routine with some CONFIG_USER_ONLY ifdefs in between. Regards, Bharata.
diff --git a/exec.c b/exec.c index 7115403..c8da9d4 100644 --- a/exec.c +++ b/exec.c @@ -596,6 +596,7 @@ void cpu_exec_exit(CPUState *cpu) return; } + QTAILQ_REMOVE(&cpus, cpu, node); bitmap_clear(cpu_index_map, cpu->cpu_index, 1); cpu->cpu_index = -1; } @@ -614,6 +615,15 @@ static int cpu_get_free_index(Error **errp) void cpu_exec_exit(CPUState *cpu) { + cpu_list_lock(); + if (cpu->cpu_index == -1) { + cpu_list_unlock(); + return; + } + + QTAILQ_REMOVE(&cpus, cpu, node); + cpu->cpu_index = -1; + cpu_list_unlock(); } #endif