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openmpi/src/mca/mpi/ptl/base/ptl_base_match.c
2004-01-14 03:23:45 +00:00

493 строки
16 KiB
C

/** @file */
/*
* $HEADER$
*/
#include <stdio.h>
#include "mca/mpi/pml/pml.h"
#include "mca/mpi/pml/base/pml_base_recvfrag.h"
#include "lam/threads/mutex.h"
#include "lam/constants.h"
#include "mpi/communicator/communicator.h"
#include "mca/mpi/pml/base/pml_base_header.h"
#include "mca/mpi/pml/base/pml_base_comm.h"
#include "lam/lfc/list.h"
#include "mca/mpi/ptl/base/ptl_base_match.h"
#include "mca/mpi/pml/pml.h"
/**
* RCS/CTS receive side matching
*
* @param frag_header list of parameters needed for matching
* This list is also embeded in frag_desc,
* but this allows to save a memory copy when
* a match is made in this routine. (IN)
* @param frag_desc pointer to receive fragment which we want
* to match (IN/OUT). If a match is not made,
* frag_header is copied to frag_desc.
* @param match_made parameter indicating if we matched frag_desc/
* frag_header (OUT)
* @param additional_matches if a match is made with frag_desc, we
* may be able to match fragments that previously
* have arrived out-of-order. If this is the
* case, the associted fratment descriptors are
* put on this list for further processing. (OUT)
*
* @return LAM error code
*
* This routine is used to try and match a newly arrived message fragment
* to pre-posted receives. The following assumptions are made
* - fragments are received out of order
* - for long messages, e.g. more than one fragment, a RTS/CTS algorithm
* is used.
* - 2nd and greater fragments include a receive descriptor pointer
* - fragments may be dropped
* - fragments may be corrupt
* - this routine may be called simoultaneously by more than one thread
*/
int mca_ptl_base_match(mca_pml_base_reliable_hdr_t *frag_header,
mca_pml_base_recv_frag_t *frag_desc, int *match_made,
lam_list_t *additional_matches)
{
/* local variables */
mca_pml_base_sequence_t frag_msg_seq_num,next_msg_seq_num_expected;
lam_communicator_t *comm_ptr;
mca_pml_base_recv_request_t *matched_receive;
mca_pml_comm_t *pml_comm;
int frag_src;
/* initialization */
*match_made=0;
/* communicator pointer */
comm_ptr=lam_comm_lookup(frag_header->hdr_base.hdr_contextid);
pml_comm=(mca_pml_comm_t *)comm_ptr->c_pml_comm;
/* source sequence number */
frag_msg_seq_num = frag_header->hdr_msg_seq_num;
/* get fragment communicator source rank */
frag_src = frag_header->hdr_frag_seq_num;
/* get next expected message sequence number - if threaded
* run, lock to make sure that if another thread is processing
* a frag from the same message a match is made only once.
* Also, this prevents other posted receives (for a pair of
* end points) from being processed, and potentially "loosing"
* the fragment.
*/
THREAD_LOCK((pml_comm->c_matching_lock)+frag_src);
/* get sequence number of next message that can be processed */
next_msg_seq_num_expected = *((pml_comm->c_next_msg_seq_num)+frag_src);
if (frag_msg_seq_num == next_msg_seq_num_expected) {
/*
* This is the sequence number we were expecting,
* so we can try matching it to already posted
* receives.
*/
/* We're now expecting the next sequence number. */
(pml_comm->c_next_msg_seq_num[frag_src])++;
/* see if receive has already been posted */
matched_receive = mca_ptl_base_check_recieves_for_match(frag_header,
pml_comm);
/* if match found, process data */
if (matched_receive) {
/*
* if threaded, ok to release lock, since the posted
* receive is not on any queue, so it won't be
* matched again, and the fragment can be processed
* w/o any conflict from other threads - locks will
* be used where concurent access needs to be managed.
*/
/* set flag indicating the input fragment was matched */
*match_made=1;
/* associate the receive descriptor with the fragment
* descriptor */
frag_desc->matched_recv=matched_receive;
/*
* update deliverd sequence number information,
* if need be.
*/
} else {
/* if no match found, place on unexpected queue - need to
* lock to prevent probe from interfering with updating
* the list */
THREAD_LOCK((pml_comm->unexpected_frags_lock)+frag_src);
lam_list_append( ((pml_comm->unexpected_frags)+frag_src),
(lam_list_item_t *)frag_desc);
THREAD_UNLOCK((pml_comm->unexpected_frags_lock)+frag_src);
/* now that the fragment is on the list, ok to
* release match - other matches may be attempted */
THREAD_UNLOCK((pml_comm->c_matching_lock)+frag_src);
}
/*
* Now that new message has arrived, check to see if
* any fragments on the c_frags_cant_match list
* may now be used to form new matchs
*/
if (lam_list_get_size((pml_comm->frags_cant_match)+frag_src)) {
/* initialize list to empty */
lam_list_set_size(additional_matches,0);
/* need to handle this -- lam_check_cantmatch_for_match();
* */
}
/*
* mark message as done, if it has completed - need to mark
* it this late to avoid a race condition with another thread
* waiting to complete a recv, completing, and try to free the
* communicator before the current thread is done referencing
* this communicator - is this true ?
*/
} else {
/*
* This message comes after the next expected, so it
* is ahead of sequence. Save it for later.
*/
lam_list_append( ((pml_comm->frags_cant_match)+frag_src),
(lam_list_item_t *)frag_desc);
/* now that the fragment is on the list, ok to
* release match - other matches may be attempted */
THREAD_UNLOCK((pml_comm->c_matching_lock)+frag_src);
}
return LAM_SUCCESS;
}
/**
* Upper level routine for matching a recieved message header to posted
* receives.
*
* @param frag_header Matching data from recived fragment (IN)
*
* @param pml_comm Pointer to the communicator structure used for
* matching purposes. (IN)
*
* @return Matched receive
*
* try and match frag to posted receives The calling routine
* garantees that no other thread will access the posted receive
* queues while this routine is being executed.
* This routine assumes that the appropriate matching locks are
* set by the upper level routine.
*/
mca_pml_base_recv_request_t *mca_ptl_base_check_recieves_for_match
(mca_pml_base_reliable_hdr_t *frag_header, mca_pml_comm_t *pml_comm)
{
/* local parameters */
mca_pml_base_recv_request_t *return_match;
int frag_src;
/* initialization */
return_match=(mca_pml_base_recv_request_t *)NULL;
/*
* figure out what sort of matching logic to use, if need to
* look only at "specific" recieves, or "wild" receives,
* or if we need to traverse both sets at the same time.
*/
frag_src = frag_header->hdr_frag_seq_num;
if (lam_list_get_size((pml_comm->specific_receives)+frag_src) == 0 ){
/*
* There are only wild irecvs, so specialize the algorithm.
*/
return_match = check_wild_receives_for_match(frag_header, pml_comm);
} else if (lam_list_get_size(&(pml_comm->wild_receives)) == 0 ) {
/*
* There are only specific irecvs, so specialize the algorithm.
*/
return_match = check_specific_receives_for_match(frag_header,
pml_comm);
} else {
/*
* There are some of each.
*/
return_match = check_specific_and_wild_receives_for_match(frag_header,
pml_comm);
}
return return_match;
}
/**
* Try and match the incoming message fragment to the list of
* "wild" receives
*
* @param frag_header Matching data from recived fragment (IN)
*
* @param pml_comm Pointer to the communicator structure used for
* matching purposes. (IN)
*
* @return Matched receive
*
* This routine assumes that the appropriate matching locks are
* set by the upper level routine.
*/
mca_pml_base_recv_request_t *check_wild_receives_for_match(
mca_pml_base_reliable_hdr_t *frag_header,
mca_pml_comm_t *pml_comm)
{
/* local parameters */
mca_pml_base_recv_request_t *return_match, *wild_recv;
int frag_user_tag,recv_user_tag;
/* initialization */
return_match=(mca_pml_base_recv_request_t *)NULL;
frag_user_tag=frag_header->hdr_base.hdr_user_tag;
/*
* Loop over the wild irecvs - no need to lock, the upper level
* locking is protecting from having other threads trying to
* change this list.
*/
for(wild_recv = (mca_pml_base_recv_request_t *)
lam_list_get_first(&(pml_comm->wild_receives));
wild_recv != (mca_pml_base_recv_request_t *)
lam_list_get_end(&(pml_comm->wild_receives));
wild_recv = (mca_pml_base_recv_request_t *)
((lam_list_item_t *)wild_recv)->lam_list_next) {
recv_user_tag = wild_recv->super.req_tag;
if (
/* exact tag match */
(frag_user_tag == recv_user_tag) ||
/* wild tag match - negative tags (except for
* LAM_ANY_TAG) are reserved for internal use, and will
* not be matched with LAM_ANY_TAG */
( (recv_user_tag == LAM_ANY_TAG) && (0 <= frag_user_tag) ) )
{
/*
* Mark that this is the matching irecv, and go to process it.
*/
return_match = wild_recv;
/* remove this irecv from the postd wild ireceive list */
lam_list_remove_item(&(pml_comm->wild_receives),
(lam_list_item_t *)wild_recv);
/* found match - no need to continue */
break;
}
}
//
return return_match;
}
/**
* Try and match the incoming message fragment to the list of
* "specific" receives
*
* @param frag_header Matching data from recived fragment (IN)
*
* @param pml_comm Pointer to the communicator structure used for
* matching purposes. (IN)
*
* @return Matched receive
*
* This routine assumes that the appropriate matching locks are
* set by the upper level routine.
*/
mca_pml_base_recv_request_t *check_specific_receives_for_match(
mca_pml_base_reliable_hdr_t *frag_header,
mca_pml_comm_t *pml_comm)
{
/* local variables */
mca_pml_base_recv_request_t *specific_recv, *return_match;
int frag_src,recv_user_tag,frag_user_tag;
/* initialization */
return_match=(mca_pml_base_recv_request_t *)NULL;
frag_src = frag_header->hdr_frag_seq_num;
frag_user_tag=frag_header->hdr_base.hdr_user_tag;
/*
* Loop over the specific irecvs.
*/
for(specific_recv = (mca_pml_base_recv_request_t *)
lam_list_get_first((pml_comm->specific_receives)+frag_src);
specific_recv != (mca_pml_base_recv_request_t *)
lam_list_get_end((pml_comm->specific_receives)+frag_src);
specific_recv = (mca_pml_base_recv_request_t *)
((lam_list_item_t *)specific_recv)->lam_list_next) {
/*
* Check for a match
*/
recv_user_tag = specific_recv->super.req_tag;
if ( (frag_user_tag == recv_user_tag) ||
( (recv_user_tag == LAM_ANY_TAG) && (0 <= frag_user_tag) ) ) {
/*
* Match made
*/
return_match = specific_recv;
/* remove descriptor from posted specific ireceive list */
lam_list_remove_item((pml_comm->specific_receives)+frag_src,
(lam_list_item_t *)specific_recv);
break;
}
}
return return_match;
}
/**
* Try and match the incoming message fragment to the list of
* "wild" receives and "specific" receives. Used when both types
* of receives have been posted, i.e. when we need to coordinate
* between multiple lists to make sure ordered delivery occurs.
*
* @param frag_header Matching data from recived fragment (IN)
*
* @param pml_comm Pointer to the communicator structure used for
* matching purposes. (IN)
*
* @return Matched receive
*
* This routine assumes that the appropriate matching locks are
* set by the upper level routine.
*/
mca_pml_base_recv_request_t *check_specific_and_wild_receives_for_match(
mca_pml_base_reliable_hdr_t *frag_header,
mca_pml_comm_t *pml_comm)
{
/* local variables */
mca_pml_base_recv_request_t *specific_recv, *wild_recv, *return_match;
mca_pml_base_sequence_t wild_recv_seq_num, specific_recv_seq_num;
int frag_src,frag_user_tag, wild_recv_tag, specific_recv_tag;
/* initialization */
return_match=(mca_pml_base_recv_request_t *)NULL;
frag_src = frag_header->hdr_frag_seq_num;
frag_user_tag=frag_header->hdr_base.hdr_user_tag;
/*
* We know that when this is called, both specific and wild irecvs
* have been posted.
*/
specific_recv = (mca_pml_base_recv_request_t *)
lam_list_get_first((pml_comm->specific_receives)+frag_src);
wild_recv = (mca_pml_base_recv_request_t *)
lam_list_get_first(&(pml_comm->wild_receives));
specific_recv_seq_num = specific_recv->sequence_number;
wild_recv_seq_num = wild_recv->sequence_number;
while (true) {
if (wild_recv_seq_num < specific_recv_seq_num) {
/*
* wild recv is earlier than the specific one.
*/
/*
* try and match
*/
wild_recv_tag = wild_recv->super.req_tag;
if ( (frag_user_tag == wild_recv_tag) ||
( (wild_recv_tag == LAM_ANY_TAG) && (0 <= frag_user_tag) ) ) {
/*
* Match made
*/
return_match=wild_recv;
/* remove this recv from the wild receive queue */
lam_list_remove_item(&(pml_comm->wild_receives),
(lam_list_item_t *)wild_recv);
return return_match;
}
/*
* No match, go to the next.
*/
wild_recv=(mca_pml_base_recv_request_t *)
((lam_list_item_t *)wild_recv)->lam_list_next;
/*
* If that was the last wild one, just look at the
* rest of the specific ones.
*/
if (wild_recv == (mca_pml_base_recv_request_t *)
lam_list_get_end(&(pml_comm->wild_receives)) )
{
return_match = check_specific_receives_for_match(frag_header,
pml_comm);
return return_match;
}
/*
* Get the sequence number for this recv, and go
* back to the top of the loop.
*/
wild_recv_seq_num = wild_recv->sequence_number;
} else {
/*
* specific recv is earlier than the wild one.
*/
specific_recv_tag=specific_recv->super.req_tag;
if ( (frag_user_tag == specific_recv_tag) ||
( (specific_recv_tag == LAM_ANY_TAG) && (0<=frag_user_tag)) )
{
/*
* Match made
*/
return_match = specific_recv;
/* remove descriptor from specific receive list */
lam_list_remove_item((pml_comm->specific_receives)+frag_src,
(lam_list_item_t *)specific_recv);
return return_match;
}
/*
* No match, go on to the next specific irecv.
*/
specific_recv = (mca_pml_base_recv_request_t *)
((lam_list_item_t *)specific_recv)->lam_list_next;
/*
* If that was the last specific irecv, process the
* rest of the wild ones.
*/
if (specific_recv == (mca_pml_base_recv_request_t *)
lam_list_get_end((pml_comm->specific_receives)+frag_src) )
{
return_match = check_wild_receives_for_match(frag_header,
pml_comm);
return return_match;
}
/*
* Get the sequence number for this recv, and go
* back to the top of the loop.
*/
specific_recv_seq_num = specific_recv->sequence_number;
}
}
}