Add a helper function to get the rv_monitor pointer for a registered monitor given its name and add its first user in rv_register_monitor().
Signed-off-by: Gabriele Monaco <[email protected]> --- kernel/trace/rv/rv.c | 28 +++++++++++++++++++--------- kernel/trace/rv/rv.h | 1 + 2 files changed, 20 insertions(+), 9 deletions(-) diff --git a/kernel/trace/rv/rv.c b/kernel/trace/rv/rv.c index f77c5865f41a..33919c5fbd6a 100644 --- a/kernel/trace/rv/rv.c +++ b/kernel/trace/rv/rv.c @@ -142,6 +142,7 @@ #include <linux/module.h> #include <linux/init.h> #include <linux/slab.h> +#include <linux/rculist.h> #ifdef CONFIG_RV_MON_EVENTS #define CREATE_TRACE_POINTS @@ -229,6 +230,18 @@ bool rv_is_container_monitor(struct rv_monitor *mon) return next->parent == mon || !mon->enable; } +struct rv_monitor *rv_get_monitor_by_name(const char *name) +{ + struct rv_monitor *m; + + list_for_each_entry_rcu(m, &rv_monitors_list, list, + lockdep_is_held(&rv_interface_lock)) { + if (strcmp(name, m->name) == 0) + return m; + } + return NULL; +} + /* * This section collects the monitor/ files and folders. */ @@ -753,7 +766,6 @@ static void destroy_monitor_dir(struct rv_monitor *mon) */ int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent) { - struct rv_monitor *r; int retval = 0; if (strnlen(monitor->name, MAX_RV_MONITOR_NAME_SIZE) == MAX_RV_MONITOR_NAME_SIZE) { @@ -764,11 +776,9 @@ int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent) guard(mutex)(&rv_interface_lock); - list_for_each_entry(r, &rv_monitors_list, list) { - if (strcmp(monitor->name, r->name) == 0) { - pr_info("Monitor %s is already registered\n", monitor->name); - return -EEXIST; - } + if (rv_get_monitor_by_name(monitor->name)) { + pr_info("Monitor %s is already registered\n", monitor->name); + return -EEXIST; } if (parent && rv_is_nested_monitor(parent)) { @@ -785,9 +795,9 @@ int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent) /* keep children close to the parent for easier visualisation */ if (parent) - list_add(&monitor->list, &parent->list); + list_add_rcu(&monitor->list, &parent->list); else - list_add_tail(&monitor->list, &rv_monitors_list); + list_add_tail_rcu(&monitor->list, &rv_monitors_list); return 0; } @@ -803,7 +813,7 @@ int rv_unregister_monitor(struct rv_monitor *monitor) guard(mutex)(&rv_interface_lock); rv_disable_monitor(monitor); - list_del(&monitor->list); + list_del_rcu(&monitor->list); destroy_monitor_dir(monitor); return 0; diff --git a/kernel/trace/rv/rv.h b/kernel/trace/rv/rv.h index 07512046e5cc..4d2c9cb284c9 100644 --- a/kernel/trace/rv/rv.h +++ b/kernel/trace/rv/rv.h @@ -27,6 +27,7 @@ int rv_disable_monitor(struct rv_monitor *mon); int rv_enable_monitor(struct rv_monitor *mon); bool rv_is_container_monitor(struct rv_monitor *mon); bool rv_is_nested_monitor(struct rv_monitor *mon); +struct rv_monitor *rv_get_monitor_by_name(const char *name); #ifdef CONFIG_RV_REACTORS int reactor_populate_monitor(struct rv_monitor *mon, struct dentry *root); -- 2.55.0
