Add cleanup function for UST app

Also, those functions uses the new ustctl_release_object function from
the UST API.

Signed-off-by: David Goulet <david.goulet@polymtl.ca>

diff --git a/lttng-sessiond/ust-app.c b/lttng-sessiond/ust-app.c
index 99fd84f3e07ca5982875ab257dd7f2146d9c225f..8520efb440e71cb84499609c1beb83bcccca8e36 100644 (file)
--- a/lttng-sessiond/ust-app.c
+++ b/lttng-sessiond/ust-app.c
@@ -31,9 +31,107 @@
 
 #include "hashtable.h"
 #include "ust-app.h"
 
 #include "hashtable.h"
 #include "ust-app.h"

-#include "../hashtable/hash.h"
-#include "ust-ctl.h"

 #include "ust-consumer.h"
 #include "ust-consumer.h"

+#include "ust-ctl.h"
+
+/*
+ * Delete ust app event safely. RCU read lock must be held before calling
+ * this function.
+ */
+static void delete_ust_app_event(int sock, struct ust_app_event *ua_event)
+{
+       /* TODO : remove context */
+       //struct ust_app_ctx *ltctx;
+       //cds_lfht_for_each_entry(lte->ctx, &iter, ltctx, node) {
+       //      delete_ust_app_ctx(sock, ltctx);
+       //}
+
+       ustctl_release_object(sock, ua_event->obj);
+       free(ua_event);
+}
+
+/*
+ * Delete ust app stream safely. RCU read lock must be held before calling
+ * this function.
+ */
+static void delete_ust_app_stream(int sock, struct ltt_ust_stream *stream)
+{
+       //TODO
+       //stream is used for passing to consumer.
+       //send_channel_streams is responsible for freeing the streams.
+       //note that this will not play well with flight recorder mode:
+       //we might need a criterion to discard the streams.
+}
+
+/*
+ * Delete ust app channel safely. RCU read lock must be held before calling
+ * this function.
+ */
+static void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan)
+{
+       int ret;
+       struct cds_lfht_iter iter;
+       struct ust_app_event *ua_event;
+       struct ltt_ust_stream *stream, *stmp;
+
+       cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
+               delete_ust_app_stream(sock, stream);
+       }
+
+       /* TODO : remove channel context */
+       //cds_lfht_for_each_entry(ltc->ctx, &iter, ltctx, node) {
+       //      hashtable_del(ltc->ctx, &iter);
+       //      delete_ust_app_ctx(sock, ltctx);
+       //}
+       //ret = hashtable_destroy(ltc->ctx);
+
+       cds_lfht_for_each_entry(ua_chan->events, &iter, ua_event, node) {
+               hashtable_del(ua_chan->events, &iter);
+               delete_ust_app_event(sock, ua_event);
+       }
+
+       ret = hashtable_destroy(ua_chan->events);
+       if (ret < 0) {
+               ERR("UST app destroy session hashtable failed");
+               goto error;
+       }
+
+error:
+       return;
+}
+
+/*
+ * Delete ust app session safely. RCU read lock must be held before calling
+ * this function.
+ */
+static void delete_ust_app_session(int sock,
+               struct ust_app_session *ua_sess)
+{
+       int ret;
+       struct cds_lfht_iter iter;
+       struct ust_app_channel *ua_chan;
+
+       if (ua_sess->metadata) {
+               /*
+                * We do NOT release the stream object and metadata object since they
+                * are release when fds are sent to the consumer.
+                */
+       }
+
+       cds_lfht_for_each_entry(ua_sess->channels, &iter, ua_chan, node) {
+               hashtable_del(ua_sess->channels, &iter);
+               delete_ust_app_channel(sock, ua_chan);
+       }
+
+       ret = hashtable_destroy(ua_sess->channels);
+       if (ret < 0) {
+               ERR("UST app destroy session hashtable failed");
+               goto error;
+       }
+
+error:
+       return;
+}

 
 /*
  * Delete a traceable application structure from the global list.
 
 /*
  * Delete a traceable application structure from the global list.


@@ -43,18 +141,16 @@ static void delete_ust_app(struct ust_app *lta)
        int ret;
        struct cds_lfht_node *node;
        struct cds_lfht_iter iter;
        int ret;
        struct cds_lfht_node *node;
        struct cds_lfht_iter iter;

+       struct ust_app_session *lts;

 
        rcu_read_lock();
 
 
        rcu_read_lock();
 

-       /* TODO: clean session hashtable */
-       free(lta->sessions);
-       close(lta->key.sock);
-

        /* Remove from apps hash table */
        node = hashtable_lookup(ust_app_ht,
                        (void *) ((unsigned long) lta->key.pid), sizeof(void *), &iter);
        if (node == NULL) {
                ERR("UST app pid %d not found in hash table", lta->key.pid);
        /* Remove from apps hash table */
        node = hashtable_lookup(ust_app_ht,
                        (void *) ((unsigned long) lta->key.pid), sizeof(void *), &iter);
        if (node == NULL) {
                ERR("UST app pid %d not found in hash table", lta->key.pid);

+               goto end;

        } else {
                ret = hashtable_del(ust_app_ht, &iter);
                if (ret) {
        } else {
                ret = hashtable_del(ust_app_ht, &iter);
                if (ret) {


@@ -70,6 +166,7 @@ static void delete_ust_app(struct ust_app *lta)
                        (void *) ((unsigned long) lta->key.sock), sizeof(void *), &iter);
        if (node == NULL) {
                ERR("UST app key %d not found in key hash table", lta->key.sock);
                        (void *) ((unsigned long) lta->key.sock), sizeof(void *), &iter);
        if (node == NULL) {
                ERR("UST app key %d not found in key hash table", lta->key.sock);

+               goto end;

        } else {
                ret = hashtable_del(ust_app_sock_key_map, &iter);
                if (ret) {
        } else {
                ret = hashtable_del(ust_app_sock_key_map, &iter);
                if (ret) {


@@ -81,8 +178,30 @@ static void delete_ust_app(struct ust_app *lta)
                }
        }
 
                }
        }
 

-       free(lta);
+       /* Socket is already closed at this point */
+
+       /* Delete ust app sessions info */
+       if (lta->sock_closed) {
+               lta->key.sock = -1;
+       }
+
+       cds_lfht_for_each_entry(lta->sessions, &iter, lts, node) {
+               hashtable_del(lta->sessions, &iter);
+               delete_ust_app_session(lta->key.sock, lts);
+       }

 
 

+       ret = hashtable_destroy(lta->sessions);
+       if (ret < 0) {
+               ERR("UST app destroy session hashtable failed");
+               goto end;
+       }
+
+       if (lta->key.sock >= 0) {
+               close(lta->key.sock);
+       }
+
+       free(lta);
+end:

        rcu_read_unlock();
 }
 
        rcu_read_unlock();
 }
 


@@ -124,7 +243,6 @@ static struct ust_app *find_app_by_sock(int sock)
                DBG2("UST app find by sock %d not found", sock);
                goto error;
        }
                DBG2("UST app find by sock %d not found", sock);
                goto error;
        }

-

        return caa_container_of(node, struct ust_app, node);
 
 error:
        return caa_container_of(node, struct ust_app, node);
 
 error:


@@ -175,7 +293,7 @@ int ust_app_register(struct ust_register_msg *msg, int sock)
 {
        struct ust_app *lta;
 
 {
        struct ust_app *lta;
 

-       lta = malloc(sizeof(struct ust_app));
+       lta = zmalloc(sizeof(struct ust_app));

        if (lta == NULL) {
                PERROR("malloc");
                return -ENOMEM;
        if (lta == NULL) {
                PERROR("malloc");
                return -ENOMEM;


@@ -241,8 +359,11 @@ void ust_app_unregister(int sock)
                goto error;
        }
 
                goto error;
        }
 

+       /* We got called because the socket was closed on the remote end. */
+       close(sock);
+       /* Using a flag because we still need "sock" as a key. */
+       lta->sock_closed = 1;

        call_rcu(&node->head, delete_ust_app_rcu);
        call_rcu(&node->head, delete_ust_app_rcu);

-

 error:
        rcu_read_unlock();
        return;
 error:
        rcu_read_unlock();
        return;

diff --git a/lttng-sessiond/ust-app.h b/lttng-sessiond/ust-app.h
index bcde8bc9cd326e4b5de5a025c58dd130ccff43b8..a69ed845162ac71adb7ca88f1aee70e9a9b1f35b 100644 (file)
--- a/lttng-sessiond/ust-app.h
+++ b/lttng-sessiond/ust-app.h
@@ -97,6 +97,7 @@ struct ust_app {
        struct cds_lfht *sessions;
        struct cds_lfht_node node;
        struct ust_app_key key;
        struct cds_lfht *sessions;
        struct cds_lfht_node node;
        struct ust_app_key key;

+       int sock_closed;

 };
 
 #ifdef HAVE_LIBLTTNG_UST_CTL
 };
 
 #ifdef HAVE_LIBLTTNG_UST_CTL

diff --git a/lttng-sessiond/ust-consumer.c b/lttng-sessiond/ust-consumer.c
index ca008d4adf65d0165d3eaca6f06f149361081594..df569368ae04f2e8faafb1b9ebbfde069fc618aa 100644 (file)
--- a/lttng-sessiond/ust-consumer.c
+++ b/lttng-sessiond/ust-consumer.c
@@ -38,7 +38,7 @@ static int send_channel_streams(int sock,
 {
        int ret, fd;
        struct lttcomm_consumer_msg lum;
 {
        int ret, fd;
        struct lttcomm_consumer_msg lum;

-       struct ltt_ust_stream *stream;
+       struct ltt_ust_stream *stream, *tmp;

 
        DBG("Sending streams of channel %s to UST consumer", uchan->name);
 
 
        DBG("Sending streams of channel %s to UST consumer", uchan->name);
 


@@ -65,7 +65,7 @@ static int send_channel_streams(int sock,
                goto error;
        }
 
                goto error;
        }
 

-       cds_list_for_each_entry(stream, &uchan->streams.head, list) {
+       cds_list_for_each_entry_safe(stream, tmp, &uchan->streams.head, list) {

                int fds[2];
 
                if (!stream->obj->shm_fd) {
                int fds[2];
 
                if (!stream->obj->shm_fd) {


@@ -97,7 +97,18 @@ static int send_channel_streams(int sock,
                        perror("send consumer stream ancillary data");
                        goto error;
                }
                        perror("send consumer stream ancillary data");
                        goto error;
                }

+
+               /*
+                * We release the stream object here, as we have passed
+                * it to the consumer.
+                */
+               /* Ensure we don't let the app know (sock = -1). */
+               ustctl_release_object(-1, stream->obj);
+               cds_list_del(&stream->list);
+               free(stream);

        }
        }

+       /* Ensure we don't let the app know (sock = -1). */
+       ustctl_release_object(-1, uchan->obj);

 
        DBG("consumer channel streams sent");
 
 
        DBG("consumer channel streams sent");
 


@@ -165,6 +176,10 @@ int ust_consumer_send_session(int consumer_fd, struct ust_app_session *usess)
                        perror("send consumer stream");
                        goto error;
                }
                        perror("send consumer stream");
                        goto error;
                }

+               /* Metadata fds passed to consumer, release them. */
+               /* Ensure we don't let the app know (sock = -1). */
+               ustctl_release_object(-1, usess->metadata->stream_obj);
+               ustctl_release_object(-1, usess->metadata->obj);

        }
 
        /* Send each channel fd streams of session */
        }
 
        /* Send each channel fd streams of session */