vm_fault_prefault9
Cluster page faults into a process's address space
Usage
#include <sys/param.h>
#include <vm/vm.h>
#include <vm/pmap.h>
void
vm_fault_prefault(pmap_t pmap, vm_offset_t addra, vm_map_entry_t entry);
Overview
The vm_fault_prefault() function provides a means of clustering pagefaults into a process's address space. It operates upon the physical map pmap. The entry argument specifies the entry to be prefaulted; the addra argument specifies the beginning of the mapping in the process's virtual address space.
It is typically called by vm_fault() after the first page fault. It benefits the execve(2) system call by eliminating repetitive calls to vm_fault(), which would otherwise be made to bring the process's executable pages into physical memory.
Implementation notes
This is a machine-independent function which calls the machine-dependent pmap_is_prefaultable(9) helper function to determine if a page may be prefaulted into physical memory.
Releases
54 releases since FreeBSD 5.2-RELEASE; the text changed 33 times.