Add calibrate command

[lttng-tools.git] / ltt-sessiond / main.c

diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c
index cb8b98c7b7141ec4b9492738ee3d87abf846d4b5..5636700d8fad1cd3127c9c6571b03a648782261d 100644 (file)
--- a/ltt-sessiond/main.c
+++ b/ltt-sessiond/main.c
@@ -99,6 +99,8 @@ static sem_t kconsumerd_sem;
 
 static pthread_mutex_t kconsumerd_pid_mutex;   /* Mutex to control kconsumerd pid assignation */
 
+static int modprobe_remove_kernel_modules(void);
+
 /*
  * Pointer initialized before thread creation.
  *
@@ -195,6 +197,9 @@ static void cleanup()
 
        DBG("Closing kernel fd");
        close(kernel_tracer_fd);
+
+       DBG("Unloading kernel modules");
+       modprobe_remove_kernel_modules();
 }
 
 /*
@@ -944,22 +949,67 @@ error:
  */
 static int modprobe_kernel_modules(void)
 {
-       int ret = 0, i = 0;
+       int ret = 0, i;
        char modprobe[256];
 
-       while (kernel_modules_list[i] != NULL) {
-               ret = snprintf(modprobe, sizeof(modprobe), "/sbin/modprobe %s",
-                               kernel_modules_list[i]);
+       for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
+               ret = snprintf(modprobe, sizeof(modprobe),
+                       "/sbin/modprobe %s%s",
+                       kernel_modules_list[i].required ? "" : "--quiet ",
+                       kernel_modules_list[i].name);
                if (ret < 0) {
                        perror("snprintf modprobe");
                        goto error;
                }
+               modprobe[sizeof(modprobe) - 1] = '\0';
                ret = system(modprobe);
+               if (ret == -1) {
+                       ERR("Unable to launch modprobe for module %s",
+                               kernel_modules_list[i].name);
+               } else if (kernel_modules_list[i].required
+                          && WEXITSTATUS(ret) != 0) {
+                       ERR("Unable to load module %s",
+                               kernel_modules_list[i].name);
+               } else {
+                       DBG("Modprobe successfully %s",
+                               kernel_modules_list[i].name);
+               }
+       }
+
+error:
+       return ret;
+}
+
+/*
+ * modprobe_remove_kernel_modules
+ * Remove modules in reverse load order.
+ */
+static int modprobe_remove_kernel_modules(void)
+{
+       int ret = 0, i;
+       char modprobe[256];
+
+       for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
+               ret = snprintf(modprobe, sizeof(modprobe),
+                       "/sbin/modprobe --remove --quiet %s",
+                       kernel_modules_list[i].name);
                if (ret < 0) {
-                       ERR("Unable to load module %s", kernel_modules_list[i]);
+                       perror("snprintf modprobe --remove");
+                       goto error;
+               }
+               modprobe[sizeof(modprobe) - 1] = '\0';
+               ret = system(modprobe);
+               if (ret == -1) {
+                       ERR("Unable to launch modprobe --remove for module %s",
+                               kernel_modules_list[i].name);
+               } else if (kernel_modules_list[i].required
+                          && WEXITSTATUS(ret) != 0) {
+                       ERR("Unable to remove module %s",
+                               kernel_modules_list[i].name);
+               } else {
+                       DBG("Modprobe removal successful %s",
+                               kernel_modules_list[i].name);
                }
-               DBG("Modprobe successfully %s", kernel_modules_list[i]);
-               i++;
        }
 
 error:
@@ -1271,6 +1321,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
        case LTTNG_CREATE_SESSION:
        case LTTNG_LIST_SESSIONS:
        case LTTNG_LIST_TRACEPOINTS:
+       case LTTNG_CALIBRATE:
                break;
        default:
                DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
@@ -1291,7 +1342,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
        }
 
        /*
-        * Check domain type for specifif "pre-action".
+        * Check domain type for specific "pre-action".
         */
        switch (cmd_ctx->lsm->domain.type) {
        case LTTNG_DOMAIN_KERNEL:
@@ -1305,21 +1356,27 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
                }
 
                /* Need a session for kernel command */
-               if (cmd_ctx->lsm->cmd_type != LTTNG_LIST_TRACEPOINTS &&
-                               cmd_ctx->session->kernel_session == NULL) {
-
-                       ret = create_kernel_session(cmd_ctx->session);
-                       if (ret < 0) {
-                               ret = LTTCOMM_KERN_SESS_FAIL;
-                               goto error;
-                       }
-
-                       /* Start the kernel consumer daemon */
-                       if (kconsumerd_pid == 0) {
-                               ret = start_kconsumerd();
+               switch (cmd_ctx->lsm->cmd_type) {
+               case LTTNG_CREATE_SESSION:
+               case LTTNG_LIST_SESSIONS:
+               case LTTNG_LIST_TRACEPOINTS:
+               case LTTNG_CALIBRATE:
+                       break;
+               default:
+                       if (cmd_ctx->session->kernel_session == NULL) {
+                               ret = create_kernel_session(cmd_ctx->session);
                                if (ret < 0) {
+                                       ret = LTTCOMM_KERN_SESS_FAIL;
                                        goto error;
                                }
+
+                               /* Start the kernel consumer daemon */
+                               if (kconsumerd_pid == 0) {
+                                       ret = start_kconsumerd();
+                                       if (ret < 0) {
+                                               goto error;
+                                       }
+                               }
                        }
                }
                break;
@@ -1999,6 +2056,37 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
                ret = LTTCOMM_OK;
                break;
        }
+
+       case LTTNG_CALIBRATE:
+       {
+               /* Setup lttng message with no payload */
+               ret = setup_lttng_msg(cmd_ctx, 0);
+               if (ret < 0) {
+                       goto setup_error;
+               }
+
+               switch (cmd_ctx->lsm->domain.type) {
+               case LTTNG_DOMAIN_KERNEL:
+               {
+                       struct lttng_kernel_calibrate kcalibrate;
+
+                       kcalibrate.type = cmd_ctx->lsm->u.calibrate.type;
+                       ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
+                       if (ret < 0) {
+                               ret = LTTCOMM_KERN_ENABLE_FAIL;
+                               goto error;
+                       }
+                       break;
+               }
+               default:
+                       /* TODO: Userspace tracing */
+                       ret = LTTCOMM_NOT_IMPLEMENTED;
+                       goto error;
+               }
+               ret = LTTCOMM_OK;
+               break;
+       }
+
        default:
                /* Undefined command */
                ret = setup_lttng_msg(cmd_ctx, 0);