diff options
Diffstat (limited to 'src/H5Oalloc.c')
| -rw-r--r-- | src/H5Oalloc.c | 186 |
1 files changed, 182 insertions, 4 deletions
diff --git a/src/H5Oalloc.c b/src/H5Oalloc.c index 3234d82..7c6cf9d 100644 --- a/src/H5Oalloc.c +++ b/src/H5Oalloc.c @@ -69,8 +69,9 @@ static htri_t H5O_alloc_extend_chunk(H5F_t *f, hid_t dxpl_id, H5O_t *oh, static unsigned H5O_alloc_new_chunk(H5F_t *f, hid_t dxpl_id, H5O_t *oh, size_t size); static htri_t H5O_move_msgs_forward(H5O_t *oh); -static htri_t H5O_merge_null(H5O_t *oh); +static htri_t H5O_merge_null(H5F_t *f, H5O_t *oh, hid_t dxpl_id); static htri_t H5O_remove_empty_chunks(H5F_t *f, H5O_t *oh, hid_t dxpl_id); +static herr_t H5O_alloc_shrink_chunk(H5F_t *f, H5O_t *oh, hid_t dxpl_id, unsigned chunkno); /*********************/ @@ -1331,13 +1332,13 @@ done: *------------------------------------------------------------------------- */ static htri_t -H5O_merge_null(H5O_t *oh) +H5O_merge_null(H5F_t *f, H5O_t *oh, hid_t dxpl_id) { hbool_t merged_msg; /* Flag to indicate that messages were merged */ hbool_t did_merging = FALSE; /* Whether any messages were merged */ htri_t ret_value; /* Return value */ - FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5O_merge_null) + FUNC_ENTER_NOAPI_NOINIT(H5O_merge_null) /* check args */ HDassert(oh != NULL); @@ -1400,6 +1401,11 @@ H5O_merge_null(H5O_t *oh) /* (Don't bother reducing size of message array for now -QAK) */ oh->nmesgs--; + /* If the merged message is too large, shrink the chunk */ + if(curr_msg->raw_size >= H5O_MESG_MAX_SIZE) + if(H5O_alloc_shrink_chunk(f, oh, dxpl_id, curr_msg->chunkno) < 0) + HGOTO_ERROR(H5E_OHDR, H5E_CANTPACK, FAIL, "unable to shrink chunk") + /* Get out of loop */ break; } /* end if */ @@ -1420,6 +1426,7 @@ H5O_merge_null(H5O_t *oh) /* Set return value */ ret_value = did_merging; +done: FUNC_LEAVE_NOAPI(ret_value) } /* H5O_merge_null() */ @@ -1603,7 +1610,7 @@ H5O_condense_header(H5F_t *f, H5O_t *oh, hid_t dxpl_id) rescan_header = TRUE; /* Scan for adjacent null messages & merge them */ - result = H5O_merge_null(oh); + result = H5O_merge_null(f, oh, dxpl_id); if(result < 0) HGOTO_ERROR(H5E_OHDR, H5E_CANTPACK, FAIL, "can't pack null header messages") if(result > 0) @@ -1624,3 +1631,174 @@ done: FUNC_LEAVE_NOAPI(ret_value) } /* H5O_condense_header() */ + +/*------------------------------------------------------------------------- + * + * Function: H5O_alloc_shrink_chunk + * + * Purpose: Shrinks a chunk, removing all null messages and any gap. + * + * Return: Non-negative on success/Negative on failure + * + * Programmer: Neil Fortner + * nfortne2@hdfgroup.org + * Oct 20 2008 + * + *------------------------------------------------------------------------- + */ +static herr_t +H5O_alloc_shrink_chunk(H5F_t *f, + H5O_t *oh, + hid_t dxpl_id, + unsigned chunkno) +{ + H5O_chunk_t *chunk = &oh->chunk[chunkno]; /* Chunk to shrink */ + H5O_mesg_t *curr_msg; + uint8_t *old_image = chunk->image; /* Old address of chunk's image in memory */ + size_t old_size = chunk->size; /* Old size of chunk */ + size_t new_size = chunk->size - chunk->gap; /* Size of shrunk chunk */ + size_t sizeof_chksum = H5O_SIZEOF_CHKSUM_OH(oh); /* Size of chunk checksum */ + size_t sizeof_msghdr = H5O_SIZEOF_MSGHDR_OH(oh); /* Size of message header */ + size_t sizeof_chkhdr = H5O_SIZEOF_CHKHDR_OH(oh); /* Size of chunk header */ + uint8_t new_size_flags = 0; /* New chunk #0 size flags */ + hbool_t adjust_size_flags = FALSE; /* Whether to adjust the chunk #0 size flags */ + size_t less_prfx_size = 0; /* Bytes removed from object header prefix */ + herr_t ret_value = SUCCEED; /* Return value */ + unsigned u; /* Index */ + + FUNC_ENTER_NOAPI_NOINIT(H5O_alloc_shrink_chunk) + + /* check args */ + HDassert(f != NULL); + + /* Loop backwards to increase the chance of seeing more null messages at the + * end of the chunk. Note that we rely on unsigned u wrapping around at the + * end. + */ + for (u = oh->nmesgs - 1, curr_msg = &oh->mesg[u]; u < oh->nmesgs; u--, curr_msg--) { + if ((H5O_NULL_ID == curr_msg->type->id) && (chunkno == curr_msg->chunkno)) { + /* Check if the message is the only one in the chunk */ + if (chunkno > 0 && (sizeof_msghdr + curr_msg->raw_size) == (new_size - sizeof_chkhdr)) { + /* Shrink the message to the minimum size */ + new_size -= curr_msg->raw_size; + curr_msg->raw_size = 0; + curr_msg->dirty = TRUE; + HDassert(new_size == sizeof_msghdr + sizeof_chkhdr); + + /* There are no more messages in this chunk, so we can exit the loop */ + break; + } /* end if */ + else { + /* Remove the message entirely */ + size_t shrink_size = curr_msg->raw_size + sizeof_msghdr; /* Amount to shrink the chunk by */ + /* If the current message is not at the end of the chunk, copy the + * data after it (except the checksum). + */ + if (curr_msg->raw + curr_msg->raw_size + < old_image + new_size - sizeof_chksum) { + unsigned v; /* Index */ + H5O_mesg_t *curr_msg2; + uint8_t *src = curr_msg->raw + curr_msg->raw_size; /* Source location */ + + /* Slide down the raw data */ + HDmemmove(curr_msg->raw - sizeof_msghdr, src, + (size_t)(old_image + new_size - sizeof_chksum - src)); + + /* Update the raw data pointers for messages after this one */ + for (v = 0, curr_msg2 = &oh->mesg[0]; v < oh->nmesgs; v++, curr_msg2++) + if ((chunkno == curr_msg2->chunkno) && (curr_msg2->raw > curr_msg->raw)) + curr_msg2->raw -= shrink_size; + } /* end if */ + + /* Adjust the new chunk size */ + new_size -= shrink_size; + + /* Release any information/memory for the message */ + H5O_msg_free_mesg(curr_msg); + + /* Remove the deleted null message from list of messages */ + if (u < (oh->nmesgs - 1)) + HDmemmove(&oh->mesg[u], &oh->mesg[u+1], ((oh->nmesgs - 1) - u) * sizeof(H5O_mesg_t)); + + /* Decrement # of messages */ + /* (Don't bother reducing size of message array for now) */ + oh->nmesgs--; + } /* end else */ + } /* end if */ + } /* end for */ + + /* Check for changing the chunk #0 data size enough to need adjusting the flags */ + if(oh->version > H5O_VERSION_1 && chunkno == 0) { + uint64_t chunk0_newsize = new_size - H5O_SIZEOF_HDR(oh); /* New size of chunk 0's data */ + size_t orig_prfx_size = 1 << (oh->flags & H5O_HDR_CHUNK0_SIZE); /* Original prefix size */ + + /* Check for moving to a 1-byte size encoding */ + if (orig_prfx_size > 1 && chunk0_newsize <= 255) { + less_prfx_size = orig_prfx_size - 1; + new_size_flags = H5O_HDR_CHUNK0_1; + adjust_size_flags = TRUE; + } /* end if */ + /* Check for moving to a 2-byte size encoding */ + else if (orig_prfx_size > 2 && chunk0_newsize <= 65535) { + less_prfx_size = orig_prfx_size - 2; + new_size_flags = H5O_HDR_CHUNK0_2; + adjust_size_flags = TRUE; + } /* end if */ + /* Check for moving to a 4-byte size encoding */ + else if (orig_prfx_size > 4 && chunk0_newsize <= 4294967295) { + less_prfx_size = orig_prfx_size - 4; + new_size_flags = H5O_HDR_CHUNK0_4; + adjust_size_flags = TRUE; + } /* end if */ + } /* end if */ + + if(adjust_size_flags) { + /* Adjust object header prefix flags */ + oh->flags &= ~H5O_HDR_CHUNK0_SIZE; + oh->flags |= new_size_flags; + + /* Slide chunk 0 data down */ + HDmemmove(chunk->image + H5O_SIZEOF_HDR(oh) - sizeof_chksum, + chunk->image + H5O_SIZEOF_HDR(oh) - sizeof_chksum + less_prfx_size, + new_size - H5O_SIZEOF_HDR(oh)); + + /* Adjust chunk size */ + new_size -= less_prfx_size; + } /* end if */ + + /* Allocate less memory space for chunk's image */ + chunk->size = new_size; + chunk->image = H5FL_BLK_REALLOC(chunk_image, old_image, chunk->size); + chunk->gap = 0; + chunk->dirty = TRUE; + if (NULL == oh->chunk[chunkno].image) + HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed") + + /* Spin through existing messages, adjusting them */ + for (u = 0, curr_msg = &oh->mesg[0]; u < oh->nmesgs; u++, curr_msg++) { + if (adjust_size_flags || (chunk->image != old_image)) + /* Adjust raw addresses for messages in this chunk to reflect new 'image' address */ + if (curr_msg->chunkno == chunkno) + curr_msg->raw = chunk->image - less_prfx_size + (curr_msg->raw - old_image); + + /* Find continuation message which points to this chunk and adjust chunk's size */ + /* (Chunk 0 doesn't have a continuation message that points to it and + * its size is directly encoded in the object header) */ + if (chunkno > 0 && (H5O_CONT_ID == curr_msg->type->id) && + (((H5O_cont_t *)(curr_msg->native))->chunkno == chunkno)) { + /* Adjust size of continuation message */ + HDassert(((H5O_cont_t *)(curr_msg->native))->size == old_size); + ((H5O_cont_t *)(curr_msg->native))->size = chunk->size; + + /* Flag continuation message as dirty */ + curr_msg->dirty = TRUE; + } /* end if */ + } /* end for */ + + /* Free the unused space in the file */ + if (H5MF_xfree(f, H5FD_MEM_OHDR, dxpl_id, chunk->addr + new_size, (hsize_t)(old_size - new_size)) < 0) + HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to shrink object header chunk") + +done: + FUNC_LEAVE_NOAPI(ret_value) +} /* H5O_alloc_shrink_chunk() */ |