*/
#include <urcu/list.h>
+#include <urcu/hlist.h>
#include <uuid/uuid.h>
#include <stdint.h>
#include <lttng/ust-abi.h>
long value;
};
+/*
+ * Entry describing an active loglevel, along with the event attribute
+ * and channel information configuring the events that need to be
+ * enabled.
+ */
+struct loglevel_entry {
+ struct cds_hlist_node hlist;
+ struct ltt_channel *chan;
+ struct lttng_ctx *ctx; /* TODO */
+ struct lttng_ust_event event_param;
+ struct cds_list_head events; /* list of events enabled */
+ struct cds_list_head list; /* per-session list of loglevels */
+ unsigned int enabled:1;
+ char name[0];
+};
+
struct lttng_event_desc {
const char *name;
void *probe_callback;
/*
* ltt_event structure is referred to by the tracing fast path. It must be
* kept small.
+ * Note about loglevel_list: this list is only used to enable/disable
+ * events on a per-loglevel basis. The events created internally by the
+ * loglevel are only freed when the session is destroyed.
*/
struct ltt_event {
unsigned int id;
union {
} u;
struct cds_list_head list; /* Event list */
+ struct cds_list_head loglevel_list; /* Event list for loglevel */
struct ust_pending_probe *pending_probe;
unsigned int metadata_dumped:1;
};
struct ltt_channel *metadata; /* Metadata channel */
struct cds_list_head chan; /* Channel list head */
struct cds_list_head events; /* Event list head */
+ struct cds_list_head loglevels; /* Loglevel list head */
struct cds_list_head list; /* Session list */
unsigned int free_chan_id; /* Next chan ID to allocate */
uuid_t uuid; /* Trace session unique ID */
struct lttng_ust_tracepoint_iter *
lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
+struct loglevel_entry *get_loglevel(const char *name);
+struct loglevel_entry *add_loglevel(const char *name,
+ struct ltt_channel *chan,
+ struct lttng_ust_event *event_param);
+void _remove_loglevel(struct loglevel_entry *e);
+int ltt_loglevel_enable(struct loglevel_entry *loglevel);
+int ltt_loglevel_disable(struct loglevel_entry *loglevel);
+int ltt_loglevel_create(struct ltt_channel *chan,
+ struct lttng_ust_event *event_param,
+ struct loglevel_entry **_entry);
+
#endif /* _LTTNG_UST_EVENTS_H */
#include <usterr-signal-safe.h>
#include <helper.h>
+#include "error.h"
#include "ltt-tracer.h"
#include "ltt-tracer-core.h"
};
static void _ltt_event_destroy(struct ltt_event *event);
+static void _ltt_loglevel_destroy(struct loglevel_entry *entry);
static void _ltt_channel_destroy(struct ltt_channel *chan);
static int _ltt_event_unregister(struct ltt_event *event);
static
uint32_t hash = jhash(name, name_len - 1, 0);
int ret = 0;
+ /* TODO:
+ * For this event, we need to lookup the loglevel. If active (in
+ * the active loglevels hash table), we must create the event.
+ */
+
head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)];
cds_hlist_for_each_entry_safe(e, node, p, head, node) {
struct ltt_event *event;
return NULL;
CDS_INIT_LIST_HEAD(&session->chan);
CDS_INIT_LIST_HEAD(&session->events);
+ CDS_INIT_LIST_HEAD(&session->loglevels);
uuid_generate(session->uuid);
cds_list_add(&session->list, &sessions);
return session;
{
struct ltt_channel *chan, *tmpchan;
struct ltt_event *event, *tmpevent;
+ struct loglevel_entry *loglevel, *tmploglevel;
int ret;
CMM_ACCESS_ONCE(session->active) = 0;
WARN_ON(ret);
}
synchronize_trace(); /* Wait for in-flight events to complete */
+ cds_list_for_each_entry_safe(loglevel, tmploglevel, &session->loglevels, list)
+ _ltt_loglevel_destroy(loglevel);
cds_list_for_each_entry_safe(event, tmpevent, &session->events, list)
_ltt_event_destroy(event);
cds_list_for_each_entry_safe(chan, tmpchan, &session->chan, list)
chan->ops->channel_destroy(chan);
}
+int ltt_loglevel_create(struct ltt_channel *chan,
+ struct lttng_ust_event *event_param,
+ struct loglevel_entry **_entry)
+{
+ struct loglevel_entry *entry;
+
+ entry = add_loglevel(event_param->name, chan, event_param);
+ if (!entry || IS_ERR(entry)) {
+ return PTR_ERR(entry);
+ }
+ *_entry = entry;
+ return 0;
+}
+
+static
+void _ltt_loglevel_destroy(struct loglevel_entry *entry)
+{
+ _remove_loglevel(entry);
+}
+
/*
* Supports event creation while tracing session is active.
*/
}
break;
case LTTNG_UST_TRACEPOINT_LOGLEVEL:
- /*
- * TODO: add tracepoint loglevel to hash table, with
- * event info. Enable all events corresponding to
- * loglevel.
- */
+ assert(0);
break;
default:
WARN_ON_ONCE(1);
#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;
+}
static const struct lttng_ust_objd_ops lttng_channel_ops;
static const struct lttng_ust_objd_ops lttng_metadata_ops;
static const struct lttng_ust_objd_ops lttng_event_ops;
+static const struct lttng_ust_objd_ops lttng_loglevel_ops;
static const struct lttng_ust_objd_ops lib_ring_buffer_objd_ops;
static const struct lttng_ust_objd_ops lttng_tracepoint_list_ops;
return ret;
}
+static
+int lttng_abi_create_loglevel(int channel_objd,
+ struct lttng_ust_event *event_param)
+{
+ struct ltt_channel *channel = objd_private(channel_objd);
+ struct loglevel_entry *loglevel;
+ int loglevel_objd, ret;
+
+ event_param->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
+ loglevel_objd = objd_alloc(NULL, <tng_loglevel_ops);
+ if (loglevel_objd < 0) {
+ ret = loglevel_objd;
+ goto objd_error;
+ }
+ /*
+ * We tolerate no failure path after loglevel creation. It will
+ * stay invariant for the rest of the session.
+ */
+ ret = ltt_loglevel_create(channel, event_param, &loglevel);
+ if (ret < 0) {
+ goto loglevel_error;
+ }
+ objd_set_private(loglevel_objd, loglevel);
+ /* The loglevel holds a reference on the channel */
+ objd_ref(channel_objd);
+ return loglevel_objd;
+
+loglevel_error:
+ {
+ int err;
+
+ err = lttng_ust_objd_unref(loglevel_objd);
+ assert(!err);
+ }
+objd_error:
+ return ret;
+}
+
/**
* lttng_channel_cmd - lttng control through object descriptors
*
return lttng_abi_open_stream(objd, stream);
}
case LTTNG_UST_EVENT:
- return lttng_abi_create_event(objd, (struct lttng_ust_event *) arg);
+ {
+ struct lttng_ust_event *event_param =
+ (struct lttng_ust_event *) arg;
+ if (event_param->instrumentation == LTTNG_UST_TRACEPOINT_LOGLEVEL) {
+ return lttng_abi_create_loglevel(objd, event_param);
+ } else {
+ return lttng_abi_create_event(objd, event_param);
+ }
+ }
case LTTNG_UST_CONTEXT:
return lttng_abi_add_context(objd,
(struct lttng_ust_context *) arg,
.cmd = lttng_event_cmd,
};
+/**
+ * lttng_loglevel_cmd - lttng control through object descriptors
+ *
+ * @objd: the object descriptor
+ * @cmd: the command
+ * @arg: command arg
+ *
+ * This object descriptor implements lttng commands:
+ * LTTNG_UST_CONTEXT
+ * Prepend a context field to each record of events of this
+ * loglevel.
+ * LTTNG_UST_ENABLE
+ * Enable recording for these loglevel events (weak enable)
+ * LTTNG_UST_DISABLE
+ * Disable recording for these loglevel events (strong disable)
+ */
+static
+long lttng_loglevel_cmd(int objd, unsigned int cmd, unsigned long arg)
+{
+ struct loglevel_entry *loglevel = objd_private(objd);
+
+ switch (cmd) {
+ case LTTNG_UST_CONTEXT:
+ return -ENOSYS; /* not implemented yet */
+#if 0
+ return lttng_abi_add_context(objd,
+ (struct lttng_ust_context *) arg,
+ &loglevel->ctx, loglevel->chan->session);
+#endif
+ case LTTNG_UST_ENABLE:
+ return ltt_loglevel_enable(loglevel);
+ case LTTNG_UST_DISABLE:
+ return ltt_loglevel_disable(loglevel);
+ default:
+ return -EINVAL;
+ }
+}
+
+static
+int lttng_loglevel_release(int objd)
+{
+ struct loglevel_entry *loglevel = objd_private(objd);
+
+ if (loglevel)
+ return lttng_ust_objd_unref(loglevel->chan->objd);
+ return 0;
+}
+
+/* TODO: filter control ioctl */
+static const struct lttng_ust_objd_ops lttng_loglevel_ops = {
+ .release = lttng_loglevel_release,
+ .cmd = lttng_loglevel_cmd,
+};
+
void lttng_ust_abi_exit(void)
{
lttng_ust_abi_close_in_progress = 1;