Cleanup mmap consuming

[lttng-tools.git] / liblttkconsumerd / lttkconsumerd.c

diff --git a/liblttkconsumerd/lttkconsumerd.c b/liblttkconsumerd/lttkconsumerd.c
index d4908d16c9c43bd01023698d91e76efab34ebb88..29f1f95d566e7befe7bcc06e5dde1fbcd9f01117 100644 (file)
--- a/liblttkconsumerd/lttkconsumerd.c
+++ b/liblttkconsumerd/lttkconsumerd.c
@@ -127,11 +127,18 @@ static int kconsumerd_find_session_fd(int fd)
  */
 static void kconsumerd_del_fd(struct kconsumerd_fd *lcf)
 {
+       int ret;
        pthread_mutex_lock(&kconsumerd_data.lock);
        cds_list_del(&lcf->list);
        if (kconsumerd_data.fds_count > 0) {
                kconsumerd_data.fds_count--;
                if (lcf != NULL) {
+                       if (lcf->mmap_base != NULL) {
+                               ret = munmap(lcf->mmap_base, lcf->mmap_len);
+                               if (ret != 0) {
+                                       perror("munmap");
+                               }
+                       }
                        if (lcf->out_fd != 0) {
                                close(lcf->out_fd);
                        }
@@ -168,6 +175,9 @@ static int kconsumerd_add_fd(struct lttcomm_kconsumerd_msg *buf, int consumerd_f
        tmp_fd->max_sb_size = buf->max_sb_size;
        tmp_fd->out_fd = 0;
        tmp_fd->out_fd_offset = 0;
+       tmp_fd->mmap_len = 0;
+       tmp_fd->mmap_base = NULL;
+       tmp_fd->output = buf->output;
        strncpy(tmp_fd->path_name, buf->path_name, PATH_MAX);
        tmp_fd->path_name[PATH_MAX - 1] = '\0';
 
@@ -185,6 +195,24 @@ static int kconsumerd_add_fd(struct lttcomm_kconsumerd_msg *buf, int consumerd_f
                                tmp_fd->sessiond_fd, tmp_fd->consumerd_fd, tmp_fd->out_fd);
        }
 
+       if (tmp_fd->output == LTTNG_EVENT_MMAP) {
+               /* get the len of the mmap region */
+               ret = kernctl_get_mmap_len(tmp_fd->consumerd_fd, &tmp_fd->mmap_len);
+               if (ret != 0) {
+                       ret = errno;
+                       perror("kernctl_get_mmap_len");
+                       goto end;
+               }
+
+               tmp_fd->mmap_base = mmap(NULL, tmp_fd->mmap_len,
+                               PROT_READ, MAP_PRIVATE, tmp_fd->consumerd_fd, 0);
+               if (tmp_fd->mmap_base == MAP_FAILED) {
+                       perror("Error mmaping");
+                       ret = -1;
+                       goto end;
+               }
+       }
+
        cds_list_add(&tmp_fd->list, &kconsumerd_data.fd_list.head);
        kconsumerd_data.fds_count++;
        kconsumerd_data.need_update = 1;
@@ -259,33 +287,13 @@ static int kconsumerd_update_poll_array(struct kconsumerd_local_data *ctx,
 int kconsumerd_on_read_subbuffer_mmap(struct kconsumerd_local_data *ctx,
                struct kconsumerd_fd *kconsumerd_fd, unsigned long len)
 {
-       unsigned long mmap_len, mmap_offset, padded_len, padding_len;
-       char *mmap_base;
+       unsigned long mmap_offset;
        char *padding = NULL;
        long ret = 0;
        off_t orig_offset = kconsumerd_fd->out_fd_offset;
        int fd = kconsumerd_fd->consumerd_fd;
        int outfd = kconsumerd_fd->out_fd;
 
-       /* get the padded subbuffer size to know the padding required */
-       ret = kernctl_get_padded_subbuf_size(fd, &padded_len);
-       if (ret != 0) {
-               ret = errno;
-               perror("kernctl_get_padded_subbuf_size");
-               goto end;
-       }
-       padding_len = padded_len - len;
-       padding = malloc(padding_len * sizeof(char));
-       memset(padding, '\0', padding_len);
-
-       /* get the len of the mmap region */
-       ret = kernctl_get_mmap_len(fd, &mmap_len);
-       if (ret != 0) {
-               ret = errno;
-               perror("kernctl_get_mmap_len");
-               goto end;
-       }
-
        /* get the offset inside the fd to mmap */
        ret = kernctl_get_mmap_read_offset(fd, &mmap_offset);
        if (ret != 0) {
@@ -294,15 +302,8 @@ int kconsumerd_on_read_subbuffer_mmap(struct kconsumerd_local_data *ctx,
                goto end;
        }
 
-       mmap_base = mmap(NULL, mmap_len, PROT_READ, MAP_PRIVATE, fd, mmap_offset);
-       if (mmap_base == MAP_FAILED) {
-               perror("Error mmaping");
-               ret = -1;
-               goto end;
-       }
-
        while (len > 0) {
-               ret = write(outfd, mmap_base, len);
+               ret = write(outfd, kconsumerd_fd->mmap_base + mmap_offset, len);
                if (ret >= len) {
                        len = 0;
                } else if (ret < 0) {
@@ -316,14 +317,6 @@ int kconsumerd_on_read_subbuffer_mmap(struct kconsumerd_local_data *ctx,
                kconsumerd_fd->out_fd_offset += ret;
        }
 
-       /* once all the data is written, write the padding to disk */
-       ret = write(outfd, padding, padding_len);
-       if (ret < 0) {
-               ret = errno;
-               perror("Error writing padding to file");
-               goto end;
-       }
-
        /*
         * This does a blocking write-and-wait on any page that belongs to the
         * subbuffer prior to the one we just wrote.
@@ -914,7 +907,7 @@ void *kconsumerd_thread_receive_fds(void *data)
                /* we received a command to add or update fds */
                ret = kconsumerd_consumerd_recv_fd(ctx, sock, kconsumerd_sockpoll,
                                tmp.payload_size, tmp.cmd_type);
-               if (ret <= 0) {
+               if (ret < 0) {
                        ERR("Receiving the FD, exiting");
                        goto end;
                }