diff options
Diffstat (limited to 'main.c')
| -rw-r--r-- | main.c | 50 |
1 files changed, 21 insertions, 29 deletions
@@ -6,7 +6,7 @@ #include "proc.h" #include "x86.h" -static void enterothers(void); +static void startothers(void); static void mpmain(void) __attribute__((noreturn)); extern pde_t *kpgdir; @@ -33,7 +33,7 @@ main(void) ideinit(); // disk if(!ismp) timerinit(); // uniprocessor timer - enterothers(); // start other processors (must come before kinit; must use boot_alloc) + startothers(); // start other processors (must come before kinit; must use enter_alloc) kinit(); // initialize memory allocator userinit(); // first user process (must come after kinit) // Finish setting up this processor in mpmain. @@ -42,7 +42,7 @@ main(void) // Other CPUs jump here from entryother.S. static void -mpboot(void) +mpenter(void) { switchkvm(); seginit(); @@ -56,22 +56,22 @@ mpmain(void) { cprintf("cpu%d: starting\n", cpu->id); idtinit(); // load idt register - xchg(&cpu->booted, 1); // tell enterothers() we're up + xchg(&cpu->started, 1); // tell startothers() we're up scheduler(); // start running processes } -pde_t bootpgdir[]; +pde_t enterpgdir[]; -// Start the non-boot processors. +// Start the non-boot (AP) processors. static void -enterothers(void) +startothers(void) { extern uchar _binary_entryother_start[], _binary_entryother_size[]; uchar *code; struct cpu *c; char *stack; - // Write bootstrap code to unused memory at 0x7000. + // Write entry code to unused memory at 0x7000. // The linker has placed the image of entryother.S in // _binary_entryother_start. code = p2v(0x7000); @@ -81,44 +81,36 @@ enterothers(void) if(c == cpus+cpunum()) // We've started already. continue; - // Tell entryother.S what stack to use, the address of mpboot and pgdir; + // Tell entryother.S what stack to use, the address of mpenter and pgdir; // We cannot use kpgdir yet, because the AP processor is running in low - // memory, so we use bootpgdir for the APs too. kalloc can return addresses + // memory, so we use enterpgdir for the APs too. kalloc can return addresses // above 4Mbyte (the machine may have much more physical memory than 4Mbyte), which - // aren't mapped by bootpgdir, so we must allocate a stack using boot_alloc(); + // aren't mapped by enterpgdir, so we must allocate a stack using enter_alloc(); // This introduces the constraint that xv6 cannot use kalloc until after these - // last boot_alloc invocations. - stack = boot_alloc(); + // last enter_alloc invocations. + stack = enter_alloc(); *(void**)(code-4) = stack + KSTACKSIZE; - *(void**)(code-8) = mpboot; - *(int**)(code-12) = (void *) v2p(bootpgdir); + *(void**)(code-8) = mpenter; + *(int**)(code-12) = (void *) v2p(enterpgdir); lapicstartap(c->id, v2p(code)); // wait for cpu to finish mpmain() - while(c->booted == 0) + while(c->started == 0) ; } } -// Boot page table used in multiboot.S and entryother.S. +// Boot page table used in entry.S and entryother.S. // Page directories (and page tables), must start on a page boundary, -// hence the "__aligned__" attribute. Also, because of restrictions -// related to linking and static initializers, we use "x + PTE_P" -// here, rather than the more standard "x | PTE_P". Everywhere else -// you should use "|" to combine flags. +// hence the "__aligned__" attribute. // Use PTE_PS in page directory entry to enable 4Mbyte pages. -pte_t dev_pgtable[NPTENTRIES]; -pte_t entry_pgtable[NPTENTRIES]; - __attribute__((__aligned__(PGSIZE))) -pde_t bootpgdir[NPDENTRIES] = { +pde_t enterpgdir[NPDENTRIES] = { // Map VA's [0, 4MB) to PA's [0, 4MB) - [0] - = (0) + PTE_P + PTE_W + PTE_PS, + [0] = (0) + PTE_P + PTE_W + PTE_PS, // Map VA's [KERNBASE, KERNBASE+4MB) to PA's [0, 4MB) - [KERNBASE>>PDXSHIFT] - = (0) + PTE_P + PTE_W + PTE_PS, + [KERNBASE>>PDXSHIFT] = (0) + PTE_P + PTE_W + PTE_PS, }; //PAGEBREAK! |