Move health into its own common/ static library

[lttng-tools.git] / src / bin / lttng-sessiond / context.c

diff --git a/src/bin/lttng-sessiond/context.c b/src/bin/lttng-sessiond/context.c
index 74afd4e0cad5ff87d307de751672ad1ae86bad61..6aacbad0ea1c96ad3375739ca908f765f1ba4370 100644 (file)
--- a/src/bin/lttng-sessiond/context.c
+++ b/src/bin/lttng-sessiond/context.c
@@ -39,6 +39,9 @@ static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
        int ret;
        struct ltt_kernel_channel *kchan;
 
+       assert(ksession);
+       assert(kctx);
+
        DBG("Adding kernel context to all channels");
 
        /* Go over all channels */
@@ -64,6 +67,9 @@ static int add_kctx_to_channel(struct lttng_kernel_context *kctx,
 {
        int ret;
 
+       assert(kchan);
+       assert(kctx);
+
        DBG("Add kernel context to channel '%s'", kchan->channel->name);
 
        ret = kernel_add_channel_context(kchan, kctx);
@@ -89,6 +95,10 @@ static int add_uctx_to_channel(struct ltt_ust_session *usess, int domain,
        struct lttng_ht_iter iter;
        struct lttng_ht_node_ulong *uctx_node;
 
+       assert(usess);
+       assert(uchan);
+       assert(ctx);
+
        /* Create ltt UST context */
        uctx = trace_ust_create_context(ctx);
        if (uctx == NULL) {
@@ -108,16 +118,21 @@ static int add_uctx_to_channel(struct ltt_ust_session *usess, int domain,
                goto error;
        }
 
+       rcu_read_lock();
+
        /* Lookup context before adding it */
        lttng_ht_lookup(uchan->ctx, (void *)((unsigned long)uctx->ctx.ctx), &iter);
        uctx_node = lttng_ht_iter_get_node_ulong(&iter);
        if (uctx_node != NULL) {
                ret = -EEXIST;
+               rcu_read_unlock();
                goto error;
        }
 
        /* Add ltt UST context node to ltt UST channel */
        lttng_ht_add_unique_ulong(uchan->ctx, &uctx->node);
+       rcu_read_unlock();
+       cds_list_add_tail(&uctx->list, &uchan->ctx_list);
 
        DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
 
@@ -138,6 +153,10 @@ int context_kernel_add(struct ltt_kernel_session *ksession,
        struct ltt_kernel_channel *kchan;
        struct lttng_kernel_context kctx;
 
+       assert(ksession);
+       assert(ctx);
+       assert(channel_name);
+
        /* Setup kernel context structure */
        switch (ctx->ctx) {
        case LTTNG_EVENT_CONTEXT_PID:
@@ -183,7 +202,7 @@ int context_kernel_add(struct ltt_kernel_session *ksession,
                        LTTNG_SYMBOL_NAME_LEN);
        kctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 
-       if (strlen(channel_name) == 0) {
+       if (*channel_name == '\0') {
                ret = add_kctx_all_channels(ksession, &kctx);
                if (ret != LTTNG_OK) {
                        goto error;
@@ -219,6 +238,12 @@ int context_ust_add(struct ltt_ust_session *usess, int domain,
        struct lttng_ht *chan_ht;
        struct ltt_ust_channel *uchan = NULL;
 
+       assert(usess);
+       assert(ctx);
+       assert(channel_name);
+
+       rcu_read_lock();
+
        /*
         * Define which channel's hashtable to use from the domain or quit if
         * unknown domain.
@@ -238,7 +263,7 @@ int context_ust_add(struct ltt_ust_session *usess, int domain,
        }
 
        /* Get UST channel if defined */
-       if (strlen(channel_name) != 0) {
+       if (channel_name[0] != '\0') {
                uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
                if (uchan == NULL) {
                        ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
@@ -250,6 +275,7 @@ int context_ust_add(struct ltt_ust_session *usess, int domain,
                /* Add ctx to channel */
                ret = add_uctx_to_channel(usess, domain, uchan, ctx);
        } else {
+               rcu_read_lock();
                /* Add ctx all events, all channels */
                cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
                        ret = add_uctx_to_channel(usess, domain, uchan, ctx);
@@ -258,6 +284,7 @@ int context_ust_add(struct ltt_ust_session *usess, int domain,
                                continue;
                        }
                }
+               rcu_read_unlock();
        }
 
        switch (ret) {
@@ -279,5 +306,6 @@ int context_ust_add(struct ltt_ust_session *usess, int domain,
        }
 
 error:
+       rcu_read_unlock();
        return ret;
 }