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openmpi/opal/mca/btl/sm/btl_sm.h
Ralph Castain 552c9ca5a0 George did the work and deserves all the credit for it. Ralph did the merge, and deserves whatever blame results from errors in it :-)
WHAT:    Open our low-level communication infrastructure by moving all necessary components (btl/rcache/allocator/mpool) down in OPAL

All the components required for inter-process communications are currently deeply integrated in the OMPI layer. Several groups/institutions have express interest in having a more generic communication infrastructure, without all the OMPI layer dependencies.  This communication layer should be made available at a different software level, available to all layers in the Open MPI software stack. As an example, our ORTE layer could replace the current OOB and instead use the BTL directly, gaining access to more reactive network interfaces than TCP.  Similarly, external software libraries could take advantage of our highly optimized AM (active message) communication layer for their own purpose.  UTK with support from Sandia, developped a version of Open MPI where the entire communication infrastucture has been moved down to OPAL (btl/rcache/allocator/mpool). Most of the moved components have been updated to match the new schema, with few exceptions (mainly BTLs where I have no way of compiling/testing them). Thus, the completion of this RFC is tied to being able to completing this move for all BTLs. For this we need help from the rest of the Open MPI community, especially those supporting some of the BTLs.  A non-exhaustive list of BTLs that qualify here is: mx, portals4, scif, udapl, ugni, usnic.

This commit was SVN r32317.
2014-07-26 00:47:28 +00:00

565 строки
18 KiB
C

/*
* Copyright (c) 2004-2007 The Trustees of Indiana University and Indiana
* University Research and Technology
* Corporation. All rights reserved.
* Copyright (c) 2004-2012 The University of Tennessee and The University
* of Tennessee Research Foundation. All rights
* reserved.
* Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
* University of Stuttgart. All rights reserved.
* Copyright (c) 2004-2005 The Regents of the University of California.
* All rights reserved.
* Copyright (c) 2006-2007 Voltaire. All rights reserved.
* Copyright (c) 2009-2010 Cisco Systems, Inc. All rights reserved.
* Copyright (c) 2010-2013 Los Alamos National Security, LLC.
* All rights reserved.
* Copyright (c) 2010-2012 IBM Corporation. All rights reserved.
* $COPYRIGHT$
*
* Additional copyrights may follow
*
* $HEADER$
*/
/**
* @file
*/
#ifndef MCA_BTL_SM_H
#define MCA_BTL_SM_H
#include "opal_config.h"
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif /* HAVE_STDINT_H */
#ifdef HAVE_SCHED_H
#include <sched.h>
#endif /* HAVE_SCHED_H */
#if OPAL_BTL_SM_HAVE_KNEM
#include "knem_io.h"
#endif /* OPAL_BTL_SM_HAVE_KNEM */
#include "opal/util/bit_ops.h"
#include "opal/class/opal_free_list.h"
#include "opal/mca/btl/btl.h"
#include "opal/util/proc.h"
#include "opal/mca/common/sm/common_sm.h"
BEGIN_C_DECLS
/*
* Shared Memory FIFOs
*
* The FIFO is implemented as a circular queue with head and tail pointers
* (integer indices). For efficient wraparound indexing, the size of the
* queue is constrained to be a power of two and we "&" indices with a "mask".
*
* More than one process can write to the FIFO head. Therefore, there is a head
* lock. One cannot write until the head slot is empty, indicated by the special
* queue entry SM_FIFO_FREE.
*
* Only the receiver can read the FIFO tail. Therefore, the tail lock is
* required only in multithreaded applications. If a tail read returns the
* SM_FIFO_FREE value, that means the FIFO is empty. Once a non-FREE value
* has been read, the queue slot is *not* automatically reset to SM_FIFO_FREE.
* Rather, read tail slots are reset "lazily" (see "lazy_free" and "num_to_clear")
* to reduce the number of memory barriers and improve performance.
*
* Since the FIFO lives in shared memory that is mapped differently into
* each address space, the "queue" pointer is relative (each process must
* add its own offset) and the queue_recv pointer is meaningful only in the
* receiver's address space.
*
* Since multiple processes access different parts of the FIFO structure in
* different ways, we introduce padding to keep different parts on different
* cachelines.
*/
#define SM_FIFO_FREE (void *) (-2)
/* We can't use opal_cache_line_size here because we need a
compile-time constant for padding the struct. We can't really have
a compile-time constant that is portable, either (e.g., compile on
one machine and run on another). So just use a big enough cache
line that should hopefully be good in most places. */
#define SM_CACHE_LINE_PAD 128
struct sm_fifo_t {
/* This queue pointer is used only by the heads. */
volatile void **queue;
char pad0[SM_CACHE_LINE_PAD - sizeof(void **)];
/* This lock is used by the heads. */
opal_atomic_lock_t head_lock;
char pad1[SM_CACHE_LINE_PAD - sizeof(opal_atomic_lock_t)];
/* This index is used by the head holding the head lock. */
volatile int head;
char pad2[SM_CACHE_LINE_PAD - sizeof(int)];
/* This mask is used "read only" by all processes. */
unsigned int mask;
char pad3[SM_CACHE_LINE_PAD - sizeof(int)];
/* The following are used only by the tail. */
volatile void **queue_recv;
opal_atomic_lock_t tail_lock;
volatile int tail;
int num_to_clear;
int lazy_free;
char pad4[SM_CACHE_LINE_PAD - sizeof(void **) -
sizeof(opal_atomic_lock_t) -
sizeof(int) * 3];
};
typedef struct sm_fifo_t sm_fifo_t;
/*
* Shared Memory resource managment
*/
#if OPAL_ENABLE_PROGRESS_THREADS == 1
#define DATA (char)0
#define DONE (char)1
#endif
typedef struct mca_btl_sm_mem_node_t {
mca_mpool_base_module_t* sm_mpool; /**< shared memory pool */
} mca_btl_sm_mem_node_t;
/**
* Shared Memory (SM) BTL module.
*/
struct mca_btl_sm_component_t {
mca_btl_base_component_2_0_0_t super; /**< base BTL component */
int sm_free_list_num; /**< initial size of free lists */
int sm_free_list_max; /**< maximum size of free lists */
int sm_free_list_inc; /**< number of elements to alloc when growing free lists */
int sm_max_procs; /**< upper limit on the number of processes using the shared memory pool */
int sm_extra_procs; /**< number of extra procs to allow */
char* sm_mpool_name; /**< name of shared memory pool module */
mca_mpool_base_module_t **sm_mpools; /**< shared memory pools (one for each memory node) */
mca_mpool_base_module_t *sm_mpool; /**< mpool on local node */
void* sm_mpool_base; /**< base address of shared memory pool */
size_t eager_limit; /**< first fragment size */
size_t max_frag_size; /**< maximum (second and beyone) fragment size */
opal_mutex_t sm_lock;
mca_common_sm_module_t *sm_seg; /**< description of shared memory segment */
volatile sm_fifo_t **shm_fifo; /**< pointer to fifo 2D array in shared memory */
char **shm_bases; /**< pointer to base pointers in shared memory */
uint16_t *shm_mem_nodes; /**< pointer to mem noded in shared memory */
sm_fifo_t **fifo; /**< cached copy of the pointer to the 2D
fifo array. The address in the shared
memory segment sm_ctl_header is a relative,
but this one, in process private memory, is
a real virtual address */
uint16_t *mem_nodes; /**< cached copy of mem nodes of each local rank */
unsigned int fifo_size; /**< number of FIFO queue entries */
unsigned int fifo_lazy_free; /**< number of reads before lazy fifo free is triggered */
int nfifos; /**< number of FIFOs per receiver */
int32_t num_smp_procs; /**< current number of smp procs on this host */
int32_t my_smp_rank; /**< My SMP process rank. Used for accessing
* SMP specfic data structures. */
ompi_free_list_t sm_frags_eager; /**< free list of sm first */
ompi_free_list_t sm_frags_max; /**< free list of sm second */
ompi_free_list_t sm_frags_user;
ompi_free_list_t sm_first_frags_to_progress; /**< list of first
fragments that are
awaiting resources */
struct mca_btl_base_endpoint_t **sm_peers;
opal_free_list_t pending_send_fl;
int num_outstanding_frags; /**< number of fragments sent but not yet returned to free list */
int num_pending_sends; /**< total number on all of my pending-send queues */
int mem_node;
int num_mem_nodes;
#if OPAL_ENABLE_PROGRESS_THREADS == 1
char sm_fifo_path[PATH_MAX]; /**< path to fifo used to signal this process */
int sm_fifo_fd; /**< file descriptor corresponding to opened fifo */
opal_thread_t sm_fifo_thread;
#endif
struct mca_btl_sm_t **sm_btls;
struct mca_btl_sm_frag_t **table;
size_t sm_num_btls;
size_t sm_max_btls;
#if OPAL_BTL_SM_HAVE_KNEM
/* Knem capabilities info */
struct knem_cmd_info knem_info;
#endif /* OPAL_BTL_SM_HAVE_KNEM */
/** MCA: should we be using knem or not? neg=try but continue if
not available, 0=don't try, 1=try and fail if not available */
int use_knem;
/** MCA: minimal message size (bytes) to offload on DMA engine
when using knem */
unsigned int knem_dma_min;
/** MCA: how many simultaneous ongoing knem operations to
support */
int knem_max_simultaneous;
/** If we want DMA and DMA is supported, this will be loaded with
KNEM_FLAG_DMA. Otherwise, it'll be 0. */
int knem_dma_flag;
/** MCA: should we be using CMA or not?
0 = no, 1 = yes */
int use_cma;
/* /// well-known file names for sm and sm mpool init /// */
char *sm_mpool_ctl_file_name;
char *sm_mpool_rndv_file_name;
char *sm_ctl_file_name;
char *sm_rndv_file_name;
};
typedef struct mca_btl_sm_component_t mca_btl_sm_component_t;
OPAL_MODULE_DECLSPEC extern mca_btl_sm_component_t mca_btl_sm_component;
/**
* SM BTL Interface
*/
struct mca_btl_sm_t {
mca_btl_base_module_t super; /**< base BTL interface */
bool btl_inited; /**< flag indicating if btl has been inited */
mca_btl_base_module_error_cb_fn_t error_cb;
#if OPAL_BTL_SM_HAVE_KNEM
/* File descriptor for knem */
int knem_fd;
/* Array of knem status items for non-blocking knem requests */
knem_status_t *knem_status_array;
/* Array of fragments currently being moved by knem non-blocking
operations */
struct mca_btl_sm_frag_t **knem_frag_array;
/* First free/available location in knem_status_array */
int knem_status_first_avail;
/* First currently-being used location in the knem_status_array */
int knem_status_first_used;
/* Number of status items currently in use */
int knem_status_num_used;
#endif /* OPAL_BTL_SM_HAVE_KNEM */
};
typedef struct mca_btl_sm_t mca_btl_sm_t;
OPAL_MODULE_DECLSPEC extern mca_btl_sm_t mca_btl_sm;
struct btl_sm_pending_send_item_t
{
opal_free_list_item_t super;
void *data;
};
typedef struct btl_sm_pending_send_item_t btl_sm_pending_send_item_t;
/***
* FIFO support for sm BTL.
*/
/***
* One or more FIFO components may be a pointer that must be
* accessed by multiple processes. Since the shared region may
* be mmapped differently into each process's address space,
* these pointers will be relative to some base address. Here,
* we define macros to translate between relative addresses and
* virtual addresses.
*/
#define VIRTUAL2RELATIVE(VADDR ) ((long)(VADDR) - (long)mca_btl_sm_component.shm_bases[mca_btl_sm_component.my_smp_rank])
#define RELATIVE2VIRTUAL(OFFSET) ((long)(OFFSET) + (long)mca_btl_sm_component.shm_bases[mca_btl_sm_component.my_smp_rank])
static inline int sm_fifo_init(int fifo_size, mca_mpool_base_module_t *mpool,
sm_fifo_t *fifo, int lazy_free)
{
int i, qsize;
/* figure out the queue size (a power of two that is at least 1) */
qsize = opal_next_poweroftwo_inclusive (fifo_size);
/* allocate the queue in the receiver's address space */
fifo->queue_recv = (volatile void **)mpool->mpool_alloc(
mpool, sizeof(void *) * qsize, opal_cache_line_size, 0, NULL);
if(NULL == fifo->queue_recv) {
return OPAL_ERR_OUT_OF_RESOURCE;
}
/* initialize the queue */
for ( i = 0; i < qsize; i++ )
fifo->queue_recv[i] = SM_FIFO_FREE;
/* shift queue address to be relative */
fifo->queue = (volatile void **) VIRTUAL2RELATIVE(fifo->queue_recv);
/* initialize the locks */
opal_atomic_init(&(fifo->head_lock), OPAL_ATOMIC_UNLOCKED);
opal_atomic_init(&(fifo->tail_lock), OPAL_ATOMIC_UNLOCKED);
opal_atomic_unlock(&(fifo->head_lock)); /* should be unnecessary */
opal_atomic_unlock(&(fifo->tail_lock)); /* should be unnecessary */
/* other initializations */
fifo->head = 0;
fifo->mask = qsize - 1;
fifo->tail = 0;
fifo->num_to_clear = 0;
fifo->lazy_free = lazy_free;
return OPAL_SUCCESS;
}
static inline int sm_fifo_write(void *value, sm_fifo_t *fifo)
{
volatile void **q = (volatile void **) RELATIVE2VIRTUAL(fifo->queue);
/* if there is no free slot to write, report exhausted resource */
opal_atomic_rmb();
if ( SM_FIFO_FREE != q[fifo->head] )
return OPAL_ERR_OUT_OF_RESOURCE;
/* otherwise, write to the slot and advance the head index */
q[fifo->head] = value;
opal_atomic_wmb();
fifo->head = (fifo->head + 1) & fifo->mask;
return OPAL_SUCCESS;
}
static inline void *sm_fifo_read(sm_fifo_t *fifo)
{
void *value;
/* read the next queue entry */
value = (void *) fifo->queue_recv[fifo->tail];
opal_atomic_rmb();
/* if you read a non-empty slot, advance the tail pointer */
if ( SM_FIFO_FREE != value ) {
fifo->tail = ( fifo->tail + 1 ) & fifo->mask;
fifo->num_to_clear += 1;
/* check if it's time to free slots, which we do lazily */
if ( fifo->num_to_clear >= fifo->lazy_free ) {
int i = (fifo->tail - fifo->num_to_clear ) & fifo->mask;
while ( fifo->num_to_clear > 0 ) {
fifo->queue_recv[i] = SM_FIFO_FREE;
i = (i+1) & fifo->mask;
fifo->num_to_clear -= 1;
}
opal_atomic_wmb();
}
}
return value;
}
/**
* shared memory component progress.
*/
extern int mca_btl_sm_component_progress(void);
/**
* Register a callback function that is called on error..
*
* @param btl (IN) BTL module
* @return Status indicating if cleanup was successful
*/
int mca_btl_sm_register_error_cb(
struct mca_btl_base_module_t* btl,
mca_btl_base_module_error_cb_fn_t cbfunc
);
/**
* Cleanup any resources held by the BTL.
*
* @param btl BTL instance.
* @return OPAL_SUCCESS or error status on failure.
*/
extern int mca_btl_sm_finalize(
struct mca_btl_base_module_t* btl
);
/**
* PML->BTL notification of change in the process list.
* PML->BTL Notification that a receive fragment has been matched.
* Called for message that is send from process with the virtual
* address of the shared memory segment being different than that of
* the receiver.
*
* @param btl (IN)
* @param proc (IN)
* @param peer (OUT)
* @return OPAL_SUCCESS or error status on failure.
*
*/
extern int mca_btl_sm_add_procs(
struct mca_btl_base_module_t* btl,
size_t nprocs,
struct opal_proc_t **procs,
struct mca_btl_base_endpoint_t** peers,
struct opal_bitmap_t* reachability
);
/**
* PML->BTL notification of change in the process list.
*
* @param btl (IN) BTL instance
* @param proc (IN) Peer process
* @param peer (IN) Peer addressing information.
* @return Status indicating if cleanup was successful
*
*/
extern int mca_btl_sm_del_procs(
struct mca_btl_base_module_t* btl,
size_t nprocs,
struct opal_proc_t **procs,
struct mca_btl_base_endpoint_t **peers
);
/**
* Allocate a segment.
*
* @param btl (IN) BTL module
* @param size (IN) Request segment size.
*/
extern mca_btl_base_descriptor_t* mca_btl_sm_alloc(
struct mca_btl_base_module_t* btl,
struct mca_btl_base_endpoint_t* endpoint,
uint8_t order,
size_t size,
uint32_t flags
);
/**
* Return a segment allocated by this BTL.
*
* @param btl (IN) BTL module
* @param segment (IN) Allocated segment.
*/
extern int mca_btl_sm_free(
struct mca_btl_base_module_t* btl,
mca_btl_base_descriptor_t* segment
);
/**
* Pack data
*
* @param btl (IN) BTL module
* @param peer (IN) BTL peer addressing
*/
struct mca_btl_base_descriptor_t* mca_btl_sm_prepare_src(
struct mca_btl_base_module_t* btl,
struct mca_btl_base_endpoint_t* endpoint,
mca_mpool_base_registration_t* registration,
struct opal_convertor_t* convertor,
uint8_t order,
size_t reserve,
size_t* size,
uint32_t flags
);
/**
* Initiate an inlined send to the peer or return a descriptor.
*
* @param btl (IN) BTL module
* @param peer (IN) BTL peer addressing
*/
extern int mca_btl_sm_sendi( struct mca_btl_base_module_t* btl,
struct mca_btl_base_endpoint_t* endpoint,
struct opal_convertor_t* convertor,
void* header,
size_t header_size,
size_t payload_size,
uint8_t order,
uint32_t flags,
mca_btl_base_tag_t tag,
mca_btl_base_descriptor_t** descriptor );
/**
* Initiate a send to the peer.
*
* @param btl (IN) BTL module
* @param peer (IN) BTL peer addressing
*/
extern int mca_btl_sm_send(
struct mca_btl_base_module_t* btl,
struct mca_btl_base_endpoint_t* endpoint,
struct mca_btl_base_descriptor_t* descriptor,
mca_btl_base_tag_t tag
);
#if OPAL_BTL_SM_HAVE_KNEM || OPAL_BTL_SM_HAVE_CMA
/*
* Synchronous knem/cma get
*/
extern int mca_btl_sm_get_sync(
struct mca_btl_base_module_t* btl,
struct mca_btl_base_endpoint_t* endpoint,
struct mca_btl_base_descriptor_t* des );
extern struct mca_btl_base_descriptor_t* mca_btl_sm_prepare_dst(
struct mca_btl_base_module_t* btl,
struct mca_btl_base_endpoint_t* endpoint,
struct mca_mpool_base_registration_t* registration,
struct opal_convertor_t* convertor,
uint8_t order,
size_t reserve,
size_t* size,
uint32_t flags);
#endif /* OPAL_BTL_SM_HAVE_KNEM || OPAL_BTL_SM_HAVE_CMA */
#if OPAL_BTL_SM_HAVE_KNEM
/*
* Asynchronous knem get
*/
extern int mca_btl_sm_get_async(
struct mca_btl_base_module_t* btl,
struct mca_btl_base_endpoint_t* endpoint,
struct mca_btl_base_descriptor_t* des );
#endif /* OPAL_BTL_SM_HAVE_KNEM */
extern void mca_btl_sm_dump(struct mca_btl_base_module_t* btl,
struct mca_btl_base_endpoint_t* endpoint,
int verbose);
/**
* Fault Tolerance Event Notification Function
* @param state Checkpoint Stae
* @return OPAL_SUCCESS or failure status
*/
int mca_btl_sm_ft_event(int state);
#if OPAL_ENABLE_PROGRESS_THREADS == 1
void mca_btl_sm_component_event_thread(opal_object_t*);
#endif
#if OPAL_ENABLE_PROGRESS_THREADS == 1
#define MCA_BTL_SM_SIGNAL_PEER(peer) \
{ \
unsigned char cmd = DATA; \
if(write(peer->fifo_fd, &cmd, sizeof(cmd)) != sizeof(cmd)) { \
opal_output(0, "mca_btl_sm_send: write fifo failed: errno=%d\n", errno); \
} \
}
#else
#define MCA_BTL_SM_SIGNAL_PEER(peer)
#endif
END_C_DECLS
#endif