diff options
Diffstat (limited to 'src/H5Distore.c')
| -rw-r--r-- | src/H5Distore.c | 82 |
1 files changed, 80 insertions, 2 deletions
diff --git a/src/H5Distore.c b/src/H5Distore.c index cbd7a0f..5182d29 100644 --- a/src/H5Distore.c +++ b/src/H5Distore.c @@ -1821,9 +1821,7 @@ H5D_istore_readvv(H5F_t *f, const struct H5D_dxpl_cache_t *dxpl_cache, hid_t dxp { H5D_istore_ud1_t udata; /*B-tree pass-through */ haddr_t chunk_addr; /* Chunk address on disk */ -#ifndef NDEBUG size_t u; /* Local index variables */ -#endif ssize_t ret_value; /* Return value */ FUNC_ENTER_NOAPI(H5D_istore_readvv, FAIL); @@ -1886,6 +1884,86 @@ HDfprintf(stderr,"%s: mem_offset_arr[%Zu]=%Hu\n",FUNC,*mem_curr_seq,mem_offset_a unsigned idx_hint=0; /* Cache index hint */ ssize_t naccessed; /* Number of bytes accessed in chunk */ + /* If the chunk address is not defined, check if the fill value is + * undefined also. If both situations hold, don't bother copying + * values to the destination buffer, since they will just be + * garbage. + * + * Ideally, this will eventually be checked at a higher level and + * the entire I/O operation on the chunk will be skipped. -QAK + */ + if(!H5F_addr_defined(chunk_addr)) { + const H5O_fill_t *fill=&(dset->dcpl_cache.fill); /* Fill value info */ + H5D_fill_time_t fill_time=dset->dcpl_cache.fill_time; /* Fill time */ + H5D_fill_value_t fill_status; + H5D_rdcc_t *rdcc = &(dset->cache.chunk);/*raw data chunk cache*/ + hbool_t found = FALSE; /*already in cache? */ + + /* Check if the chunk is in the cache (but hasn't been written to disk yet) */ + if (rdcc->nslots>0) { + unsigned idx=H5D_HASH(dset,store->chunk.index); /* Cache entry index */ + H5D_rdcc_ent_t *ent = rdcc->slot[idx]; /* Cache entry */ + + /* Potential match... */ + if (ent) { + for (u=0, found=TRUE; u<dset->layout.u.chunk.ndims; u++) { + if (store->chunk.offset[u]!=ent->offset[u]) { + found = FALSE; + break; + } /* end if */ + } /* end for */ + } /* end if */ + } /* end if */ + + /* If the chunk is in the cache, then it must have valid data */ + if(!found) { + /* Check if the fill value is defined */ + if (H5P_is_fill_value_defined(fill, &fill_status) < 0) + HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't tell if fill value defined"); + + /* If we are never to return fill values, or if we would return them + * but they aren't set, process the entire set of I/O vectors and + * get out now. + */ + if(fill_time==H5D_FILL_TIME_NEVER || + (fill_time==H5D_FILL_TIME_IFSET && fill_status!=H5D_FILL_VALUE_USER_DEFINED)) { + size_t size; /* Size of sequence in bytes */ + size_t v; /* Local index variable */ + ssize_t bytes_processed=0; /* Eventual return value */ + + /* Work through all the sequences */ + for(u=*mem_curr_seq, v=*chunk_curr_seq; u<mem_max_nseq && v<chunk_max_nseq; ) { + /* Choose smallest buffer to write */ + if(chunk_len_arr[v]<mem_len_arr[u]) + size=chunk_len_arr[v]; + else + size=mem_len_arr[u]; + + /* Update source information */ + chunk_len_arr[v]-=size; + chunk_offset_arr[v]+=size; + if(chunk_len_arr[v]==0) + v++; + + /* Update destination information */ + mem_len_arr[u]-=size; + mem_offset_arr[u]+=size; + if(mem_len_arr[u]==0) + u++; + + /* Increment number of bytes copied */ + bytes_processed+=(ssize_t)size; + } /* end for */ + + /* Update current sequence vectors */ + *mem_curr_seq=u; + *chunk_curr_seq=v; + + HGOTO_DONE(bytes_processed); + } /* end if */ + } /* end if */ + } /* end if */ + /* * Lock the chunk, copy from application to chunk, then unlock the * chunk. |