rt_benchs/communication_techniques/include/batch_queue_common_comm.h

79 lines
2.0 KiB
C

#ifndef _BATCH_QUEUE_COMMON_COMM_H_
#define _BATCH_QUEUE_COMMON_COMM_H_ 1
#include <stdint.h>
#include <unistd.h>
/* Non standard include */
#include <commtech.h>
#ifndef BUF_SIZE
#define BUF_SIZE (32 * CACHE_LINE_SIZE)
#endif
struct channel
{
/* buf must be the first field to allow the buf_mask test */
void * volatile buf[2][BUF_SIZE / sizeof(void *)] __attribute__ ((aligned (CACHE_LINE_SIZE)));
struct channel *mapping1; /* accesses to buf[0] and state */
struct channel *mapping2; /* accesses to buf[1] */
uintptr_t buf_mask;
int unused[20] __attribute__ ((aligned (CACHE_LINE_SIZE)));
volatile unsigned int state:1 __attribute__ ((aligned (CACHE_LINE_SIZE)));
void * volatile *sender_ptr __attribute__ ((aligned (CACHE_LINE_SIZE)));
void * volatile *receiver_ptr __attribute__ ((aligned (CACHE_LINE_SIZE)));
};
#ifndef _BATCH_QUEUE_C_
#ifndef PAGE_SIZE_HELPER
#define PAGE_SIZE_HELPER 1
uintptr_t _bq_page_mask;
void *create_comm_channel_internal(void);
static void *create_comm_channel_helper(void) __attribute__ ((unused));
static void *create_comm_channel_helper(void)
{
int ret;
struct channel *channel;
ret = sysconf(_SC_PAGESIZE);
if (ret == -1)
return NULL;
_bq_page_mask = ~(ret - 1);
channel = create_comm_channel_internal();
channel->buf_mask = sizeof channel->buf[0] - 1;
return channel;
}
#else
extern unsigned int _bq_page_mask;
#endif /* PAGE_SIZE_HELPER */
#define create_comm_channel() create_comm_channel_helper()
__BEGIN_DECLS
static inline void send(struct channel *channel, void **addr)
{
uintptr_t sender_ptr_high;
*channel->sender_ptr++ = addr;
if (unlikely(!((uintptr_t) channel->sender_ptr & channel->buf_mask)))
{
while (channel->state);
channel->state = 1;
sender_ptr_high =
(uintptr_t) channel->sender_ptr & _bq_page_mask;
if ((void *) sender_ptr_high == channel->mapping1)
channel->sender_ptr = channel->mapping2->buf[1];
else
channel->sender_ptr = channel->mapping1->buf[0];
}
}
__END_DECLS
#endif /* _BATCH_QUEUE_C_ */
#endif