diff options
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-syscfg.c')
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-syscfg.c | 51 |
1 files changed, 36 insertions, 15 deletions
diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index a70c1454b410..83dad24e0116 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -395,6 +395,8 @@ static void cscfg_remove_owned_csdev_configs(struct coresight_device *csdev, voi if (list_empty(&csdev->config_csdev_list)) return; + guard(raw_spinlock_irqsave)(&csdev->cscfg_csdev_lock); + list_for_each_entry_safe(config_csdev, tmp, &csdev->config_csdev_list, node) { if (config_csdev->config_desc->load_owner == load_owner) list_del(&config_csdev->node); @@ -867,6 +869,25 @@ unlock_exit: } EXPORT_SYMBOL_GPL(cscfg_csdev_reset_feats); +static bool cscfg_config_desc_get(struct cscfg_config_desc *config_desc) +{ + if (!atomic_fetch_inc(&config_desc->active_cnt)) { + /* must ensure that config cannot be unloaded in use */ + if (unlikely(cscfg_owner_get(config_desc->load_owner))) { + atomic_dec(&config_desc->active_cnt); + return false; + } + } + + return true; +} + +static void cscfg_config_desc_put(struct cscfg_config_desc *config_desc) +{ + if (!atomic_dec_return(&config_desc->active_cnt)) + cscfg_owner_put(config_desc->load_owner); +} + /* * This activate configuration for either perf or sysfs. Perf can have multiple * active configs, selected per event, sysfs is limited to one. @@ -890,22 +911,17 @@ static int _cscfg_activate_config(unsigned long cfg_hash) if (config_desc->available == false) return -EBUSY; - /* must ensure that config cannot be unloaded in use */ - err = cscfg_owner_get(config_desc->load_owner); - if (err) + if (!cscfg_config_desc_get(config_desc)) { + err = -EINVAL; break; + } + /* * increment the global active count - control changes to * active configurations */ atomic_inc(&cscfg_mgr->sys_active_cnt); - /* - * mark the descriptor as active so enable config on a - * device instance will use it - */ - atomic_inc(&config_desc->active_cnt); - err = 0; dev_dbg(cscfg_device(), "Activate config %s.\n", config_desc->name); break; @@ -920,9 +936,8 @@ static void _cscfg_deactivate_config(unsigned long cfg_hash) list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) { if ((unsigned long)config_desc->event_ea->var == cfg_hash) { - atomic_dec(&config_desc->active_cnt); atomic_dec(&cscfg_mgr->sys_active_cnt); - cscfg_owner_put(config_desc->load_owner); + cscfg_config_desc_put(config_desc); dev_dbg(cscfg_device(), "Deactivate config %s.\n", config_desc->name); break; } @@ -1047,7 +1062,7 @@ int cscfg_csdev_enable_active_config(struct coresight_device *csdev, unsigned long cfg_hash, int preset) { struct cscfg_config_csdev *config_csdev_active = NULL, *config_csdev_item; - const struct cscfg_config_desc *config_desc; + struct cscfg_config_desc *config_desc; unsigned long flags; int err = 0; @@ -1062,8 +1077,8 @@ int cscfg_csdev_enable_active_config(struct coresight_device *csdev, raw_spin_lock_irqsave(&csdev->cscfg_csdev_lock, flags); list_for_each_entry(config_csdev_item, &csdev->config_csdev_list, node) { config_desc = config_csdev_item->config_desc; - if ((atomic_read(&config_desc->active_cnt)) && - ((unsigned long)config_desc->event_ea->var == cfg_hash)) { + if (((unsigned long)config_desc->event_ea->var == cfg_hash) && + cscfg_config_desc_get(config_desc)) { config_csdev_active = config_csdev_item; csdev->active_cscfg_ctxt = (void *)config_csdev_active; break; @@ -1097,7 +1112,11 @@ int cscfg_csdev_enable_active_config(struct coresight_device *csdev, err = -EBUSY; raw_spin_unlock_irqrestore(&csdev->cscfg_csdev_lock, flags); } + + if (err) + cscfg_config_desc_put(config_desc); } + return err; } EXPORT_SYMBOL_GPL(cscfg_csdev_enable_active_config); @@ -1136,8 +1155,10 @@ void cscfg_csdev_disable_active_config(struct coresight_device *csdev) raw_spin_unlock_irqrestore(&csdev->cscfg_csdev_lock, flags); /* true if there was an enabled active config */ - if (config_csdev) + if (config_csdev) { cscfg_csdev_disable_config(config_csdev); + cscfg_config_desc_put(config_csdev->config_desc); + } } EXPORT_SYMBOL_GPL(cscfg_csdev_disable_active_config); |