diff options
Diffstat (limited to 'src/H5Fmpi.c')
| -rw-r--r-- | src/H5Fmpi.c | 132 |
1 files changed, 127 insertions, 5 deletions
diff --git a/src/H5Fmpi.c b/src/H5Fmpi.c index 53d2d78..78290c6 100644 --- a/src/H5Fmpi.c +++ b/src/H5Fmpi.c @@ -31,11 +31,12 @@ /***********/ /* Headers */ /***********/ -#include "H5private.h" /* Generic Functions */ -#include "H5Eprivate.h" /* Error handling */ -#include "H5Fpkg.h" /* File access */ -#include "H5FDprivate.h" /* File drivers */ -#include "H5Iprivate.h" /* IDs */ +#include "H5private.h" /* Generic Functions */ +#include "H5CXprivate.h" /* API Contexts */ +#include "H5Eprivate.h" /* Error handling */ +#include "H5Fpkg.h" /* File access */ +#include "H5FDprivate.h" /* File drivers */ +#include "H5Iprivate.h" /* IDs */ #include "H5VLnative_private.h" /* Native VOL connector */ @@ -402,4 +403,125 @@ H5F_mpi_retrieve_comm(hid_t loc_id, hid_t acspl_id, MPI_Comm *mpi_comm) done: FUNC_LEAVE_NOAPI(ret_value) } /* end H5F_mpi_retrieve_comm */ + +/*------------------------------------------------------------------------- + * Function: H5F_get_coll_metadata_reads + * + * Purpose: Determines whether collective metadata reads should be + * performed. This routine is meant to be the single source of + * truth for the collective metadata reads status, as it + * coordinates between the file-global flag and the flag set + * for the current operation in the current API context. + * + * Return: TRUE/FALSE (can't fail) + * + *------------------------------------------------------------------------- + */ +hbool_t +H5F_get_coll_metadata_reads(const H5F_t *file) +{ + H5P_coll_md_read_flag_t file_flag = H5P_USER_FALSE; + hbool_t ret_value = FALSE; + + FUNC_ENTER_NOAPI_NOERR + + HDassert(file && file->shared); + + /* Retrieve the file-global flag */ + file_flag = H5F_COLL_MD_READ(file); + + /* If file flag is set to H5P_FORCE_FALSE, exit early + * with FALSE, since collective metadata reads have + * been explicitly disabled somewhere in the library. + */ + if (H5P_FORCE_FALSE == file_flag) + ret_value = FALSE; + else { + /* If file flag is set to H5P_USER_TRUE, ignore + * any settings in the API context. A file-global + * setting of H5P_USER_TRUE for collective metadata + * reads should ignore any settings on an Access + * Property List for an individual operation. + */ + if (H5P_USER_TRUE == file_flag) + ret_value = TRUE; + else { + /* Get the collective metadata reads flag from + * the current API context. + */ + ret_value = H5CX_get_coll_metadata_read(); + } + } + + FUNC_LEAVE_NOAPI(ret_value) +} /* end H5F_get_coll_metadata_reads() */ + +/*------------------------------------------------------------------------- + * Function: H5F_set_coll_metadata_reads + * + * Purpose: Used to temporarily modify the collective metadata reads + * status. This is useful for cases where either: + * + * * Collective metadata reads are enabled, but need to be + * disabled for an operation about to occur that may trigger + * an independent metadata read (such as only rank 0 doing + * something) + * + * * Metadata reads are currently independent, but it is + * guaranteed that the application has maintained + * collectivity at the interface level (e.g., an operation + * that modifies metadata is being performed). In this case, + * it should be safe to enable collective metadata reads, + * barring any internal library issues that may occur + * + * After completion, the `file_flag` parameter will be set to + * the previous value of the file-global collective metadata + * reads flag. The `context_flag` parameter will be set to the + * previous value of the API context's collective metadata + * reads flag. Another call to this routine should be made to + * restore these values (see below warning). + * + * !! WARNING !! + * It is dangerous to modify the collective metadata reads + * status, as this can cause crashes, hangs and corruption in + * the HDF5 file when improperly done. Therefore, the + * `file_flag` and `context_flag` parameters are both + * mandatory, and it is assumed that the caller will guarantee + * these settings are restored with another call to this + * routine once the bracketed operation is complete. + * !! WARNING !! + * + * Return: Nothing + * + *------------------------------------------------------------------------- + */ +void +H5F_set_coll_metadata_reads(H5F_t *file, H5P_coll_md_read_flag_t *file_flag, hbool_t *context_flag) +{ + H5P_coll_md_read_flag_t prev_file_flag = H5P_USER_FALSE; + hbool_t prev_context_flag = FALSE; + + FUNC_ENTER_NOAPI_NOERR + + HDassert(file && file->shared); + HDassert(file_flag); + HDassert(context_flag); + + /* Save old state */ + prev_file_flag = H5F_COLL_MD_READ(file); + prev_context_flag = H5CX_get_coll_metadata_read(); + + /* Set new desired state */ + if (prev_file_flag != *file_flag) { + file->shared->coll_md_read = *file_flag; + *file_flag = prev_file_flag; + } + if (prev_context_flag != *context_flag) { + H5CX_set_coll_metadata_read(*context_flag); + *context_flag = prev_context_flag; + } + + FUNC_LEAVE_NOAPI_VOID +} /* end H5F_set_coll_metadata_reads() */ + #endif /* H5_HAVE_PARALLEL */ |