You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
36 lines
782 B
C
36 lines
782 B
C
#include "iob_internal.h"
|
|
#include <stdio.h>
|
|
#include <sys/types.h>
|
|
#include <sys/mman.h>
|
|
|
|
void iob_prefetch(io_batch* b,uint64 bytes) {
|
|
volatile char x;
|
|
iob_entry* e,* last;
|
|
if (b->bytesleft==0) return;
|
|
last=(iob_entry*)(((char*)array_start(&b->b))+array_bytes(&b->b));
|
|
e=(iob_entry*)array_start(&b->b);
|
|
if (!e) return;
|
|
for (; e<last; ++e) {
|
|
if (e->type==FROMFILE || e->type==FROMFILE_CLOSE) {
|
|
char* c,* d;
|
|
uint64 before=bytes;
|
|
if (e->n<bytes) bytes=e->n;
|
|
if (e->n>=1000000) {
|
|
long l=e->offset&4095;
|
|
d=c=mmap(0,bytes,PROT_READ,MAP_SHARED,e->fd,(e->offset|4095)+1);
|
|
bytes-=l;
|
|
if (c!=MAP_FAILED) {
|
|
while (bytes>4095) {
|
|
x=*d;
|
|
bytes-=4096;
|
|
d+=4096;
|
|
}
|
|
}
|
|
munmap(c,before);
|
|
}
|
|
return;
|
|
}
|
|
}
|
|
(void)x;
|
|
}
|