Re: [PATCH 1/1] coresight: prevent deactivate active config while enable the config

[Yeoreum Yun]

Hi James.
> > diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c
> > index a70c1454b410..dfa7dcbaf25d 100644
> > --- a/drivers/hwtracing/coresight/coresight-syscfg.c
> > +++ b/drivers/hwtracing/coresight/coresight-syscfg.c
> > @@ -953,7 +953,8 @@ int cscfg_config_sysfs_activate(struct cscfg_config_desc *config_desc, bool acti
> >   			cscfg_mgr->sysfs_active_config = cfg_hash;
> >   	} else {
> >   		/* disable if matching current value */
> > -		if (cscfg_mgr->sysfs_active_config == cfg_hash) {
> > +		if (cscfg_mgr->sysfs_active_config == cfg_hash &&
> > +		    !atomic_read(&cscfg_mgr->sys_enable_cnt)) {
> >   			_cscfg_deactivate_config(cfg_hash);
>
> So is sys_enable_cnt a global value? If a fix is needed doesn't it need to
> be a per-config refcount?
>
> Say you have two active configs, sys_enable_cnt is now 2, how do you disable
> one without it always skipping here when the other config is enabled?

Sorry to miss this one!.
Because when one configuration is enabled,
cscfg_mgr->sysfs_active_config becomes !NULL, so it wouldn't happen
there is no two activate configurations. so sys_enable_cnt wouldn't be
2.