Turn consumer "normal" error into debug statement (with comment)

[lttng-tools.git] / ltt-kconsumerd / ltt-kconsumerd.c

diff --git a/ltt-kconsumerd/ltt-kconsumerd.c b/ltt-kconsumerd/ltt-kconsumerd.c
index 64c5ccfae908499c20eeb59a5cdb305eae342a2c..ca939656b7c888d84173d460aa4582d6bbad2e22 100644 (file)
--- a/ltt-kconsumerd/ltt-kconsumerd.c
+++ b/ltt-kconsumerd/ltt-kconsumerd.c
@@ -37,12 +37,15 @@
 #include <unistd.h>
 #include <sys/mman.h>
 
+#include <lttng/lttng-kconsumerd.h>
+
 #include "lttngerr.h"
 #include "kernelctl.h"
-#include "lttkconsumerd.h"
+#include "ltt-kconsumerd.h"
+#include "lttng-sessiond-comm.h"
 
 /* the two threads (receive fd and poll) */
-pthread_t threads[2];
+static pthread_t threads[2];
 
 /* to count the number of time the user pressed ctrl+c */
 static int sigintcount = 0;
@@ -52,16 +55,14 @@ int opt_quiet;
 int opt_verbose;
 static int opt_daemon;
 static const char *progname;
-char command_sock_path[PATH_MAX]; /* Global command socket path */
-char error_sock_path[PATH_MAX]; /* Global error path */
+static char command_sock_path[PATH_MAX]; /* Global command socket path */
+static char error_sock_path[PATH_MAX]; /* Global error path */
 
-/* the liblttkconsumerd context */
-struct kconsumerd_local_data *ctx;
+/* the liblttngkconsumerd context */
+static struct lttng_kconsumerd_local_data *ctx;
 
 /*
- *  sighandler
- *
- *  Signal handler for the daemon
+ * Signal handler for the daemon
  */
 static void sighandler(int sig)
 {
@@ -70,13 +71,11 @@ static void sighandler(int sig)
                return;
        }
 
-       kconsumerd_should_exit(ctx);
+       lttng_kconsumerd_should_exit(ctx);
 }
 
 /*
- *  set_signal_handler
- *
- *  Setup signal handler for :
+ * Setup signal handler for :
  *      SIGINT, SIGTERM, SIGPIPE
  */
 static int set_signal_handler(void)
@@ -194,11 +193,9 @@ static void parse_args(int argc, char **argv)
 }
 
 /*
- * read_subbuffer
- *
- * Consume data on a file descriptor and write it on a trace file
+ * Consume data on a file descriptor and write it on a trace file.
  */
-static int read_subbuffer(struct kconsumerd_fd *kconsumerd_fd)
+static int read_subbuffer(struct lttng_kconsumerd_fd *kconsumerd_fd)
 {
        unsigned long len;
        int err;
@@ -210,12 +207,18 @@ static int read_subbuffer(struct kconsumerd_fd *kconsumerd_fd)
        err = kernctl_get_next_subbuf(infd);
        if (err != 0) {
                ret = errno;
-               perror("Reserving sub buffer failed (everything is normal, "
+               /*
+                * This is a debug message even for single-threaded consumer,
+                * because poll() have more relaxed criterions than get subbuf,
+                * so get_subbuf may fail for short race windows where poll()
+                * would issue wakeups.
+                */
+               DBG("Reserving sub buffer failed (everything is normal, "
                                "it is due to concurrency)");
                goto end;
        }
 
-       switch (DEFAULT_KERNEL_CHANNEL_OUTPUT) {
+       switch (kconsumerd_fd->output) {
                case LTTNG_EVENT_SPLICE:
                        /* read the whole subbuffer */
                        err = kernctl_get_padded_subbuf_size(infd, &len);
@@ -226,7 +229,7 @@ static int read_subbuffer(struct kconsumerd_fd *kconsumerd_fd)
                        }
 
                        /* splice the subbuffer to the tracefile */
-                       ret = kconsumerd_on_read_subbuffer_splice(ctx, kconsumerd_fd, len);
+                       ret = lttng_kconsumerd_on_read_subbuffer_splice(ctx, kconsumerd_fd, len);
                        if (ret < 0) {
                                /*
                                 * display the error but continue processing to try
@@ -237,14 +240,14 @@ static int read_subbuffer(struct kconsumerd_fd *kconsumerd_fd)
                        break;
                case LTTNG_EVENT_MMAP:
                        /* read the used subbuffer size */
-                       err = kernctl_get_subbuf_size(infd, &len);
+                       err = kernctl_get_padded_subbuf_size(infd, &len);
                        if (err != 0) {
                                ret = errno;
                                perror("Getting sub-buffer len failed.");
                                goto end;
                        }
                        /* write the subbuffer to the tracefile */
-                       ret = kconsumerd_on_read_subbuffer_mmap(ctx, kconsumerd_fd, len);
+                       ret = lttng_kconsumerd_on_read_subbuffer_mmap(ctx, kconsumerd_fd, len);
                        if (ret < 0) {
                                /*
                                 * display the error but continue processing to try
@@ -301,12 +304,12 @@ int main(int argc, char **argv)
                                KCONSUMERD_CMD_SOCK_PATH);
        }
        /* create the pipe to wake to receiving thread when needed */
-       ctx = kconsumerd_create(read_subbuffer);
+       ctx = lttng_kconsumerd_create(read_subbuffer);
        if (ctx == NULL) {
                goto error;
        }
 
-       kconsumerd_set_command_socket_path(ctx, command_sock_path);
+       lttng_kconsumerd_set_command_sock_path(ctx, command_sock_path);
        if (strlen(error_sock_path) == 0) {
                snprintf(error_sock_path, PATH_MAX,
                                KCONSUMERD_ERR_SOCK_PATH);
@@ -323,10 +326,10 @@ int main(int argc, char **argv)
        if (ret < 0) {
                WARN("Cannot connect to error socket, is ltt-sessiond started ?");
        }
-       kconsumerd_set_error_socket(ctx, ret);
+       lttng_kconsumerd_set_error_sock(ctx, ret);
 
        /* Create the thread to manage the receive of fd */
-       ret = pthread_create(&threads[0], NULL, kconsumerd_thread_receive_fds,
+       ret = pthread_create(&threads[0], NULL, lttng_kconsumerd_thread_receive_fds,
                        (void *) ctx);
        if (ret != 0) {
                perror("pthread_create");
@@ -334,7 +337,7 @@ int main(int argc, char **argv)
        }
 
        /* Create thread to manage the polling/writing of traces */
-       ret = pthread_create(&threads[1], NULL, kconsumerd_thread_poll_fds,
+       ret = pthread_create(&threads[1], NULL, lttng_kconsumerd_thread_poll_fds,
                        (void *) ctx);
        if (ret != 0) {
                perror("pthread_create");
@@ -349,16 +352,16 @@ int main(int argc, char **argv)
                }
        }
        ret = EXIT_SUCCESS;
-       kconsumerd_send_error(ctx, KCONSUMERD_EXIT_SUCCESS);
+       lttng_kconsumerd_send_error(ctx, KCONSUMERD_EXIT_SUCCESS);
        goto end;
 
 error:
        ret = EXIT_FAILURE;
-       kconsumerd_send_error(ctx, KCONSUMERD_EXIT_FAILURE);
+       lttng_kconsumerd_send_error(ctx, KCONSUMERD_EXIT_FAILURE);
 
 end:
-       kconsumerd_destroy(ctx);
-       kconsumerd_cleanup();
+       lttng_kconsumerd_destroy(ctx);
+       lttng_kconsumerd_cleanup();
 
        return ret;
 }