Use the "tail queue" from queue(3) for the delayed free list of shadow images.

Delete the little-used free-list length, dl_len, and just count up the list
entries when diagnostic code needs the length.

Extract the code for deferring shadow-image free into a new subroutine,
`vfd_swmr_idx_entry_defer_free()`.

Rename type `deferred_free_head_t` as `deferred_free_queue_t`.

Remove the disused H5F__LL_{REMOVE,PREPEND} macros.

Add some diagnostic code and #if 0'd assertions.

Change `qsort(ptr, n, sizeof(type), cmp)` to
`qsort(ptr, n, sizeof(*ptr), cmp)`.

Use a `continue` statement to lower a staircase in
H5F_update_vfd_swmr_metadata_file().

Add vfd_swmr_mdf_idx_entry_remove() to delete a shadow index entry and add the
image at that entry to a deferred-free list.  Call it whenever a page is
evicted.

Update the comment in H5PB_remove_entry() that asks if we need to remove shadow
index entries: now we *do* remove them.  Remove shadow index entries in
H5PB__evict_entry().  Also mention in the comment that the index-entry removal
performed by H5PB__evict_entry() ought to be sufficient.

1 files changed, 15 insertions, 4 deletions

diff --git a/src/H5Ftest.c b/src/H5Ftest.c
index cebbbe9..90657ef 100644
--- a/src/H5Ftest.c
+++ b/src/H5Ftest.c
@@ -526,6 +526,17 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* H5F__vfd_swmr_verify_md_hdr_and_idx() */
 
+static unsigned
+count_old_images(old_image_queue_t *old_images)
+{
+    old_image_t *old_image;
+    unsigned count = 0;
+
+    TAILQ_FOREACH(old_image, old_images, link)
+        count++;
+
+    return count;
+}
 
 
 /*-------------------------------------------------------------------------
@@ -536,15 +547,15 @@ done:
  *          --info read from the metadata file is as indicated by
  *          the input: num_entries, index
  *          --# of entries on the delayed list is as indicated by 
- *          the input: num_dl_entries
+ *          the input: nold_images
  *
  * Return:  SUCCEED/FAIL
  *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5F__vfd_swmr_writer_md_test(hid_t file_id, unsigned num_entries, H5FD_vfd_swmr_idx_entry_t *index,
-    unsigned num_dl_entries)
+H5F__vfd_swmr_writer_md_test(hid_t file_id, unsigned num_entries,
+    H5FD_vfd_swmr_idx_entry_t *index, unsigned nold_images)
 {
     H5F_t *f;                       /* File pointer */
     int md_fd = -1;                 /* The metadata file descriptor */
@@ -566,7 +577,7 @@ H5F__vfd_swmr_writer_md_test(hid_t file_id, unsigned num_entries, H5FD_vfd_swmr_
         HGOTO_ERROR(H5E_FILE, H5E_CANTALLOC, FAIL, "error updating the md file with the index")
 
     /* Verify the number of entries in the delayed list is as expected */
-    if(f->shared->dl_len < num_dl_entries)
+    if(count_old_images(&f->shared->old_images) < nold_images)
         HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "incorrect # of entries in the delayed list")
 
     /* Open the metadata file */