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#include "types.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "proc.h"
#include "x86.h"
extern pde_t *kpgdir;
extern char end[]; // first address after kernel loaded from ELF file
static void mpmain(void) __attribute__((noreturn));
static void startothers(void);
// Bootstrap processor starts running C code here.
// Allocate a real stack and switch to it, first
// doing some setup required for memory allocator to work.
int
main(uint64 mbmagic, uint64 mbaddr)
{
if(mbmagic != 0x2badb002)
panic("multiboot header not found");
kinit1(end, P2V(4*1024*1024)); // phys page allocator
kvmalloc(); // kernel page table
mpinit(); // detect other processors
lapicinit(); // interrupt controller
seginit(); // segment descriptors
picinit(); // disable pic
ioapicinit(); // another interrupt controller
consoleinit(); // console hardware
uartinit(); // serial port
pinit(); // process table
tvinit(); // trap vectors
binit(); // buffer cache
fileinit(); // file table
ideinit(); // disk
startothers(); // start other processors
kinit2(P2V(4*1024*1024), P2V(PHYSTOP)); // must come after startothers()
userinit(); // first user process
mpmain();
return 0;
}
extern struct cpu* getmycpu();
// Common CPU setup code.
static void
mpmain(void)
{
cprintf("cpu%d: starting %d\n", cpuid(), cpuid());
idtinit(); // load idt register
xchg(&(mycpu()->started), 1); // tell startothers() we're up
scheduler(); // start running processes
}
// AP processors jump here from entryother.S.
void
apmain(void)
{
switchkvm();
seginit();
lapicinit();
mpmain();
}
void apstart(void);
// Start the non-boot (AP) processors.
static void
startothers(void)
{
extern uchar _binary_entryother_start[], _binary_entryother_size[];
uchar *code;
struct cpu *c;
char *stack;
// Write entry code to unused memory at 0x7000.
// The linker has placed the image of entryother.S in
// _binary_entryother_start.
code = P2V(0x7000);
memmove(code, _binary_entryother_start, (uint64)_binary_entryother_size);
for(c = cpus; c < cpus+ncpu; c++){
if(c == mycpu()) // We've started already.
continue;
// Tell entryother.S what stack to use, where to enter, and what
// pgdir to use. We cannot use kpgdir yet, because the AP processor
// is running in low memory, so we use entrypgdir for the APs too.
stack = kalloc();
*(uint32*)(code-4) = V2P(apstart);
*(uint64*)(code-12) = (uint64) (stack+KSTACKSIZE);
lapicstartap(c->apicid, V2P(code));
// wait for cpu to finish mpmain()
while(c->started == 0)
;
}
}
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