Fix: send per-pid session id in channel creation

The registry indexing for per-pid sessions is done with a per-pid
session id. So for per-pid buffers, we need to send the per-pid session
id as well as the global session id to the consumer in order to give it
enough information if it needs to request metadata later.

This patch adds the session_id_per_pid to the channel creation message
and to the consumer. When the sessiond receives a metadata_request,
depending on the buffer type (per-pid or per-uid), it selects the right
id to do the registry lookup.

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>

diff --git a/src/bin/lttng-sessiond/consumer.c b/src/bin/lttng-sessiond/consumer.c
index 2e20878856fd1ee1ab1637b6ff297044bda58d77..345a5a1d9982342f417f8ffdde0decfb5deaccd8 100644 (file)
--- a/src/bin/lttng-sessiond/consumer.c
+++ b/src/bin/lttng-sessiond/consumer.c
@@ -684,7 +684,8 @@ void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
                unsigned char *uuid,
                uint32_t chan_id,
                uint64_t tracefile_size,
-               uint64_t tracefile_count)
+               uint64_t tracefile_count,
+               uint64_t session_id_per_pid)
 {
        assert(msg);
 
@@ -700,6 +701,7 @@ void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
        msg->u.ask_channel.output = output;
        msg->u.ask_channel.type = type;
        msg->u.ask_channel.session_id = session_id;
+       msg->u.ask_channel.session_id_per_pid = session_id_per_pid;
        msg->u.ask_channel.uid = uid;
        msg->u.ask_channel.gid = gid;
        msg->u.ask_channel.relayd_id = relayd_id;

diff --git a/src/bin/lttng-sessiond/consumer.h b/src/bin/lttng-sessiond/consumer.h
index 09f4545a03fdc1e40fb777aaff1c4f9cdf278b2d..ae28ca88583c6b4e246732055aebdbb9f34c0bbd 100644 (file)
--- a/src/bin/lttng-sessiond/consumer.h
+++ b/src/bin/lttng-sessiond/consumer.h
@@ -202,7 +202,8 @@ void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
                unsigned char *uuid,
                uint32_t chan_id,
                uint64_t tracefile_size,
-               uint64_t tracefile_count);
+               uint64_t tracefile_count,
+               uint64_t session_id_per_pid);
 void consumer_init_stream_comm_msg(struct lttcomm_consumer_msg *msg,
                enum lttng_consumer_command cmd,
                uint64_t channel_key,

diff --git a/src/bin/lttng-sessiond/ust-consumer.c b/src/bin/lttng-sessiond/ust-consumer.c
index 367e92cd32368b2b4b522834bad22010c1668cf7..e287faea996284e575b5b0c70ebbb27bf879c53f 100644 (file)
--- a/src/bin/lttng-sessiond/ust-consumer.c
+++ b/src/bin/lttng-sessiond/ust-consumer.c
@@ -157,7 +157,8 @@ static int ask_channel_creation(struct ust_app_session *ua_sess,
                        registry->uuid,
                        chan_id,
                        ua_chan->tracefile_size,
-                       ua_chan->tracefile_count);
+                       ua_chan->tracefile_count,
+                       ua_sess->id);
 
        health_code_update();
 
@@ -445,7 +446,7 @@ int ust_consumer_metadata_request(struct consumer_socket *socket)
                goto end;
        }
 
-       DBG("Metadata request received for session %u, key %" PRIu64,
+       DBG("Metadata request received for session %" PRIu64 ", key %" PRIu64,
                        request.session_id, request.key);
 
        reg_uid = buffer_reg_uid_find(request.session_id,
@@ -454,10 +455,10 @@ int ust_consumer_metadata_request(struct consumer_socket *socket)
                ust_reg = reg_uid->registry->reg.ust;
        } else {
                struct buffer_reg_pid *reg_pid =
-                       buffer_reg_pid_find(request.session_id);
+                       buffer_reg_pid_find(request.session_id_per_pid);
                if (!reg_pid) {
-                       DBG("PID registry not found for session id %u",
-                                       request.session_id);
+                       DBG("PID registry not found for session id %" PRIu64,
+                                       request.session_id_per_pid);
 
                        msg.cmd_type = LTTNG_ERR_UND;
                        (void) consumer_send_msg(socket, &msg);

diff --git a/src/common/consumer.c b/src/common/consumer.c
index 1dcc52c6a648f2d15f8f48b53b27e3fbcf67769a..76003b2a2b1222606ccc8520ec8bbacd054125ee 100644 (file)
--- a/src/common/consumer.c
+++ b/src/common/consumer.c
@@ -858,7 +858,8 @@ struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
                uint64_t relayd_id,
                enum lttng_event_output output,
                uint64_t tracefile_size,
-               uint64_t tracefile_count)
+               uint64_t tracefile_count,
+               uint64_t session_id_per_pid)
 {
        struct lttng_consumer_channel *channel;
 
@@ -871,6 +872,7 @@ struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
        channel->key = key;
        channel->refcount = 0;
        channel->session_id = session_id;
+       channel->session_id_per_pid = session_id_per_pid;
        channel->uid = uid;
        channel->gid = gid;
        channel->relayd_id = relayd_id;

diff --git a/src/common/consumer.h b/src/common/consumer.h
index 650397adaf6a6f815b14a9c50da5690565ef6c0e..b3810e007bff678801b990061bea28deb482feae 100644 (file)
--- a/src/common/consumer.h
+++ b/src/common/consumer.h
@@ -102,6 +102,11 @@ struct lttng_consumer_channel {
        int refcount;
        /* Tracing session id on the session daemon side. */
        uint64_t session_id;
+       /*
+        * Session id when requesting metadata to the session daemon for
+        * a session with per-PID buffers.
+        */
+       uint64_t session_id_per_pid;
        /* Channel trace file path name. */
        char pathname[PATH_MAX];
        /* Channel name. */
@@ -472,7 +477,8 @@ struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
                uint64_t relayd_id,
                enum lttng_event_output output,
                uint64_t tracefile_size,
-               uint64_t tracefile_count);
+               uint64_t tracefile_count,
+               uint64_t session_id_per_pid);
 void consumer_del_stream(struct lttng_consumer_stream *stream,
                struct lttng_ht *ht);
 void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,

diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
index 11830fc05a087f4f601a3156560ac5b7a6735365..fc869653da844c2238e89096e40a3750a52a4a9b 100644 (file)
--- a/src/common/kernel-consumer/kernel-consumer.c
+++ b/src/common/kernel-consumer/kernel-consumer.c
@@ -144,7 +144,7 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                                msg.u.channel.name, msg.u.channel.uid, msg.u.channel.gid,
                                msg.u.channel.relayd_id, msg.u.channel.output,
                                msg.u.channel.tracefile_size,
-                               msg.u.channel.tracefile_count);
+                               msg.u.channel.tracefile_count, 0);
                if (new_channel == NULL) {
                        lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
                        goto end_nosignal;

diff --git a/src/common/sessiond-comm/sessiond-comm.h b/src/common/sessiond-comm/sessiond-comm.h
index c0b89a1232dfebd5e5f6b09da3c82ee186bfca6d..64c8d1879063921cffb8285dee13151b474b0a51 100644 (file)
--- a/src/common/sessiond-comm/sessiond-comm.h
+++ b/src/common/sessiond-comm/sessiond-comm.h
@@ -150,7 +150,8 @@ enum lttcomm_metadata_command {
  * per PID registry indexed by session id ignoring the other values.
  */
 struct lttcomm_metadata_request_msg {
-       unsigned int session_id; /* Tracing session id */
+       uint64_t session_id; /* Tracing session id */
+       uint64_t session_id_per_pid; /* Tracing session id for per-pid */
        uint32_t bits_per_long; /* Consumer ABI */
        uint32_t uid;
        uint64_t key; /* Metadata channel key. */
@@ -342,6 +343,7 @@ struct lttcomm_consumer_msg {
                        uint32_t chan_id;                       /* Channel ID on the tracer side. */
                        uint64_t tracefile_size;        /* bytes */
                        uint32_t tracefile_count;       /* number of tracefiles */
+                       uint64_t session_id_per_pid;    /* Per-pid session ID. */
                } LTTNG_PACKED ask_channel;
                struct {
                        uint64_t key;

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index f783d4058c550033983045c93cbeddcc363028d3..e8e36d71c520602fa2c74ccd3c3c956beb9ce47d 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -114,13 +114,15 @@ error:
 static struct lttng_consumer_channel *allocate_channel(uint64_t session_id,
                const char *pathname, const char *name, uid_t uid, gid_t gid,
                int relayd_id, uint64_t key, enum lttng_event_output output,
-               uint64_t tracefile_size, uint64_t tracefile_count)
+               uint64_t tracefile_size, uint64_t tracefile_count,
+               uint64_t session_id_per_pid)
 {
        assert(pathname);
        assert(name);
 
-       return consumer_allocate_channel(key, session_id, pathname, name, uid, gid,
-                       relayd_id, output, tracefile_size, tracefile_count);
+       return consumer_allocate_channel(key, session_id, pathname, name, uid,
+                       gid, relayd_id, output, tracefile_size,
+                       tracefile_count, session_id_per_pid);
 }
 
 /*
@@ -924,7 +926,8 @@ int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                                msg.u.ask_channel.relayd_id, msg.u.ask_channel.key,
                                (enum lttng_event_output) msg.u.ask_channel.output,
                                msg.u.ask_channel.tracefile_size,
-                               msg.u.ask_channel.tracefile_count);
+                               msg.u.ask_channel.tracefile_count,
+                               msg.u.ask_channel.session_id_per_pid);
                if (!channel) {
                        goto end_channel_error;
                }
@@ -1500,10 +1503,13 @@ int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data *ctx,
        }
 
        request.session_id = channel->session_id;
+       request.session_id_per_pid = channel->session_id_per_pid;
        request.uid = channel->uid;
        request.key = channel->key;
-       DBG("Sending metadata request to sessiond, session %" PRIu64,
-                       channel->session_id);
+       DBG("Sending metadata request to sessiond, session id %" PRIu64
+                       ", per-pid %" PRIu64,
+                       channel->session_id,
+                       channel->session_id_per_pid);
 
        ret = lttcomm_send_unix_sock(ctx->consumer_metadata_socket, &request,
                        sizeof(request));