diff options
Diffstat (limited to 'kernel/trace/rv/rv.c')
| -rw-r--r-- | kernel/trace/rv/rv.c | 154 |
1 files changed, 131 insertions, 23 deletions
diff --git a/kernel/trace/rv/rv.c b/kernel/trace/rv/rv.c index 8657fc8806e7..50344aa9f7f9 100644 --- a/kernel/trace/rv/rv.c +++ b/kernel/trace/rv/rv.c @@ -162,7 +162,7 @@ struct dentry *get_monitors_root(void) /* * Interface for the monitor register. */ -static LIST_HEAD(rv_monitors_list); +LIST_HEAD(rv_monitors_list); static int task_monitor_count; static bool task_monitor_slots[RV_PER_TASK_MONITORS]; @@ -207,6 +207,30 @@ void rv_put_task_monitor_slot(int slot) } /* + * Monitors with a parent are nested, + * Monitors without a parent could be standalone or containers. + */ +bool rv_is_nested_monitor(struct rv_monitor_def *mdef) +{ + return mdef->parent != NULL; +} + +/* + * We set our list to have nested monitors listed after their parent + * if a monitor has a child element its a container. + * Containers can be also identified based on their function pointers: + * as they are not real monitors they do not need function definitions + * for enable()/disable(). Use this condition to find empty containers. + * Keep both conditions in case we have some non-compliant containers. + */ +bool rv_is_container_monitor(struct rv_monitor_def *mdef) +{ + struct rv_monitor_def *next = list_next_entry(mdef, list); + + return next->parent == mdef->monitor || !mdef->monitor->enable; +} + +/* * This section collects the monitor/ files and folders. */ static ssize_t monitor_enable_read_data(struct file *filp, char __user *user_buf, size_t count, @@ -229,7 +253,8 @@ static int __rv_disable_monitor(struct rv_monitor_def *mdef, bool sync) if (mdef->monitor->enabled) { mdef->monitor->enabled = 0; - mdef->monitor->disable(); + if (mdef->monitor->disable) + mdef->monitor->disable(); /* * Wait for the execution of all events to finish. @@ -243,6 +268,60 @@ static int __rv_disable_monitor(struct rv_monitor_def *mdef, bool sync) return 0; } +static void rv_disable_single(struct rv_monitor_def *mdef) +{ + __rv_disable_monitor(mdef, true); +} + +static int rv_enable_single(struct rv_monitor_def *mdef) +{ + int retval; + + lockdep_assert_held(&rv_interface_lock); + + if (mdef->monitor->enabled) + return 0; + + retval = mdef->monitor->enable(); + + if (!retval) + mdef->monitor->enabled = 1; + + return retval; +} + +static void rv_disable_container(struct rv_monitor_def *mdef) +{ + struct rv_monitor_def *p = mdef; + int enabled = 0; + + list_for_each_entry_continue(p, &rv_monitors_list, list) { + if (p->parent != mdef->monitor) + break; + enabled += __rv_disable_monitor(p, false); + } + if (enabled) + tracepoint_synchronize_unregister(); + mdef->monitor->enabled = 0; +} + +static int rv_enable_container(struct rv_monitor_def *mdef) +{ + struct rv_monitor_def *p = mdef; + int retval = 0; + + list_for_each_entry_continue(p, &rv_monitors_list, list) { + if (retval || p->parent != mdef->monitor) + break; + retval = rv_enable_single(p); + } + if (retval) + rv_disable_container(mdef); + else + mdef->monitor->enabled = 1; + return retval; +} + /** * rv_disable_monitor - disable a given runtime monitor * @mdef: Pointer to the monitor definition structure. @@ -251,7 +330,11 @@ static int __rv_disable_monitor(struct rv_monitor_def *mdef, bool sync) */ int rv_disable_monitor(struct rv_monitor_def *mdef) { - __rv_disable_monitor(mdef, true); + if (rv_is_container_monitor(mdef)) + rv_disable_container(mdef); + else + rv_disable_single(mdef); + return 0; } @@ -265,15 +348,10 @@ int rv_enable_monitor(struct rv_monitor_def *mdef) { int retval; - lockdep_assert_held(&rv_interface_lock); - - if (mdef->monitor->enabled) - return 0; - - retval = mdef->monitor->enable(); - - if (!retval) - mdef->monitor->enabled = 1; + if (rv_is_container_monitor(mdef)) + retval = rv_enable_container(mdef); + else + retval = rv_enable_single(mdef); return retval; } @@ -336,9 +414,9 @@ static const struct file_operations interface_desc_fops = { * the monitor dir, where the specific options of the monitor * are exposed. */ -static int create_monitor_dir(struct rv_monitor_def *mdef) +static int create_monitor_dir(struct rv_monitor_def *mdef, struct rv_monitor_def *parent) { - struct dentry *root = get_monitors_root(); + struct dentry *root = parent ? parent->root_d : get_monitors_root(); const char *name = mdef->monitor->name; struct dentry *tmp; int retval; @@ -377,7 +455,11 @@ static int monitors_show(struct seq_file *m, void *p) { struct rv_monitor_def *mon_def = p; - seq_printf(m, "%s\n", mon_def->monitor->name); + if (mon_def->parent) + seq_printf(m, "%s:%s\n", mon_def->parent->name, + mon_def->monitor->name); + else + seq_printf(m, "%s\n", mon_def->monitor->name); return 0; } @@ -514,7 +596,7 @@ static ssize_t enabled_monitors_write(struct file *filp, const char __user *user struct rv_monitor_def *mdef; int retval = -EINVAL; bool enable = true; - char *ptr; + char *ptr, *tmp; int len; if (count < 1 || count > MAX_RV_MONITOR_NAME_SIZE + 1) @@ -541,6 +623,11 @@ static ssize_t enabled_monitors_write(struct file *filp, const char __user *user retval = -EINVAL; + /* we support 1 nesting level, trim the parent */ + tmp = strstr(ptr, ":"); + if (tmp) + ptr = tmp+1; + list_for_each_entry(mdef, &rv_monitors_list, list) { if (strcmp(ptr, mdef->monitor->name) != 0) continue; @@ -613,7 +700,7 @@ static void reset_all_monitors(void) struct rv_monitor_def *mdef; list_for_each_entry(mdef, &rv_monitors_list, list) { - if (mdef->monitor->enabled) + if (mdef->monitor->enabled && mdef->monitor->reset) mdef->monitor->reset(); } } @@ -685,18 +772,19 @@ static void destroy_monitor_dir(struct rv_monitor_def *mdef) /** * rv_register_monitor - register a rv monitor. * @monitor: The rv_monitor to be registered. + * @parent: The parent of the monitor to be registered, NULL if not nested. * * Returns 0 if successful, error otherwise. */ -int rv_register_monitor(struct rv_monitor *monitor) +int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent) { - struct rv_monitor_def *r; + struct rv_monitor_def *r, *p = NULL; int retval = 0; if (strlen(monitor->name) >= MAX_RV_MONITOR_NAME_SIZE) { pr_info("Monitor %s has a name longer than %d\n", monitor->name, MAX_RV_MONITOR_NAME_SIZE); - return -1; + return -EINVAL; } mutex_lock(&rv_interface_lock); @@ -704,11 +792,26 @@ int rv_register_monitor(struct rv_monitor *monitor) list_for_each_entry(r, &rv_monitors_list, list) { if (strcmp(monitor->name, r->monitor->name) == 0) { pr_info("Monitor %s is already registered\n", monitor->name); - retval = -1; + retval = -EEXIST; goto out_unlock; } } + if (parent) { + list_for_each_entry(r, &rv_monitors_list, list) { + if (strcmp(parent->name, r->monitor->name) == 0) { + p = r; + break; + } + } + } + + if (p && rv_is_nested_monitor(p)) { + pr_info("Parent monitor %s is already nested, cannot nest further\n", + parent->name); + return -EINVAL; + } + r = kzalloc(sizeof(struct rv_monitor_def), GFP_KERNEL); if (!r) { retval = -ENOMEM; @@ -716,14 +819,19 @@ int rv_register_monitor(struct rv_monitor *monitor) } r->monitor = monitor; + r->parent = parent; - retval = create_monitor_dir(r); + retval = create_monitor_dir(r, p); if (retval) { kfree(r); goto out_unlock; } - list_add_tail(&r->list, &rv_monitors_list); + /* keep children close to the parent for easier visualisation */ + if (p) + list_add(&r->list, &p->list); + else + list_add_tail(&r->list, &rv_monitors_list); out_unlock: mutex_unlock(&rv_interface_lock); |