#include <string.h>
#include <errno.h>
#include <urcu/list.h>
+#include <urcu/hlist.h>
#include <lttng/ust-events.h>
#include <assert.h>
#include <helper.h>
#include "ltt-tracer-core.h"
+#include "jhash.h"
+#include "error.h"
/*
* probe list is protected by ust_lock()/ust_unlock().
*/
static CDS_LIST_HEAD(probe_list);
+/*
+ * Loglevel hash table, containing the active loglevels.
+ * Protected by ust lock.
+ */
+#define LOGLEVEL_HASH_BITS 6
+#define LOGLEVEL_TABLE_SIZE (1 << LOGLEVEL_HASH_BITS)
+static struct cds_hlist_head loglevel_table[LOGLEVEL_TABLE_SIZE];
+
static
const struct lttng_probe_desc *find_provider(const char *provider)
{
struct tp_list_entry, head);
return &entry->tp;
}
+
+/*
+ * Get loglevel if the loglevel is present in the loglevel hash table.
+ * Must be called with ust lock held.
+ * Returns NULL if not present.
+ */
+struct loglevel_entry *get_loglevel(const char *name)
+{
+ struct cds_hlist_head *head;
+ struct cds_hlist_node *node;
+ struct loglevel_entry *e;
+ uint32_t hash = jhash(name, strlen(name), 0);
+
+ head = &loglevel_table[hash & (LOGLEVEL_TABLE_SIZE - 1)];
+ cds_hlist_for_each_entry(e, node, head, hlist) {
+ if (!strcmp(name, e->name))
+ return e;
+ }
+ return NULL;
+}
+
+/*
+ * marshall all probes/all events and create those that fit the
+ * loglevel. Add them to the events list as created.
+ */
+static
+void _probes_create_loglevel_events(struct loglevel_entry *loglevel)
+{
+ struct lttng_probe_desc *probe_desc;
+ int i;
+
+ cds_list_for_each_entry(probe_desc, &probe_list, head) {
+ for (i = 0; i < probe_desc->nr_events; i++) {
+ const struct tracepoint_loglevel_entry *ev_ll;
+
+ if (!(probe_desc->event_desc[i]->loglevel))
+ continue;
+ ev_ll = *probe_desc->event_desc[i]->loglevel;
+ if (!strcmp(ev_ll->identifier, loglevel->name)) {
+ struct ltt_event *ev;
+ int ret;
+
+ /* create event */
+ ret = ltt_event_create(loglevel->chan,
+ &loglevel->event_param, NULL,
+ &ev);
+ /*
+ * TODO: report error.
+ */
+ if (ret)
+ continue;
+ cds_list_add(&ev->loglevel_list,
+ &loglevel->events);
+ }
+
+ }
+ }
+}
+
+/*
+ * Add the loglevel to the loglevel hash table. Must be called with
+ * ust lock held.
+ */
+struct loglevel_entry *add_loglevel(const char *name,
+ struct ltt_channel *chan,
+ struct lttng_ust_event *event_param)
+{
+ struct cds_hlist_head *head;
+ struct cds_hlist_node *node;
+ struct loglevel_entry *e;
+ size_t name_len = strlen(name) + 1;
+ uint32_t hash = jhash(name, name_len-1, 0);
+
+ head = &loglevel_table[hash & (LOGLEVEL_TABLE_SIZE - 1)];
+ cds_hlist_for_each_entry(e, node, head, hlist) {
+ if (!strcmp(name, e->name)) {
+ DBG("loglevel %s busy", name);
+ return ERR_PTR(-EEXIST); /* Already there */
+ }
+ }
+ /*
+ * Using zmalloc here to allocate a variable length element. Could
+ * cause some memory fragmentation if overused.
+ */
+ e = zmalloc(sizeof(struct loglevel_entry) + name_len);
+ if (!e)
+ return ERR_PTR(-ENOMEM);
+ memcpy(&e->name[0], name, name_len);
+ e->chan = chan;
+ e->enabled = 1;
+ memcpy(&e->event_param, event_param, sizeof(e->event_param));
+ cds_hlist_add_head(&e->hlist, head);
+ CDS_INIT_LIST_HEAD(&e->events);
+ _probes_create_loglevel_events(e);
+ cds_list_add(&e->list, &chan->session->loglevels);
+ return e;
+}
+
+/*
+ * Remove the loglevel from the loglevel hash table. Must be called with
+ * ust_lock held. Only called at session teardown.
+ */
+void _remove_loglevel(struct loglevel_entry *loglevel)
+{
+ struct ltt_event *ev, *tmp;
+
+ /*
+ * Just remove the events owned (for enable/disable) by this
+ * loglevel from the list. The session teardown will take care
+ * of freeing the event memory.
+ */
+ cds_list_for_each_entry_safe(ev, tmp, &loglevel->events, list) {
+ cds_list_del(&ev->list);
+ }
+ cds_hlist_del(&loglevel->hlist);
+ cds_list_del(&loglevel->list);
+ free(loglevel);
+}
+
+int ltt_loglevel_enable(struct loglevel_entry *loglevel)
+{
+ struct ltt_event *ev;
+ int ret;
+
+ if (loglevel->enabled)
+ return -EEXIST;
+ cds_list_for_each_entry(ev, &loglevel->events, list) {
+ ret = ltt_event_enable(ev);
+ if (ret) {
+ DBG("Error: enable error.\n");
+ return ret;
+ }
+ }
+ loglevel->enabled = 1;
+ return 0;
+}
+
+int ltt_loglevel_disable(struct loglevel_entry *loglevel)
+{
+ struct ltt_event *ev;
+ int ret;
+
+ if (!loglevel->enabled)
+ return -EEXIST;
+ cds_list_for_each_entry(ev, &loglevel->events, list) {
+ ret = ltt_event_disable(ev);
+ if (ret) {
+ DBG("Error: disable error.\n");
+ return ret;
+ }
+ }
+ loglevel->enabled = 0;
+ return 0;
+}
projects / lttng-ust.git / blobdiff