Files
2026-10-19 19:57:05 +02:00

78 lines
1.9 KiB
C

#include <zinnia/alloc.h>
#include <zinnia/atomic.h>
#include <zinnia/cmdline.h>
#include <zinnia/compiler.h>
#include <zinnia/percpu.h>
#include <zinnia/pmap.h>
#include <zinnia/utils.h>
#include <zinnia/vma.h>
#include <arch/percpu.h>
static _Atomic(size_t) num_cpus = 1;
static size_t max_cpus = SIZE_MAX;
static void smp_option(uintptr_t value) {
max_cpus = value;
}
CMDLINE_OPTION("smp", "Maximum number of CPUs to use", smp_option);
[[__used, __section(".percpu.init")]]
struct percpu percpu_bsp = {
.self = &percpu_bsp,
.id = 0,
.online = false,
};
struct percpu* percpu_new() {
const size_t pgsz = arch_mem_page_size();
const size_t stride = percpu_stride();
const size_t id = atomic_load(&num_cpus, ATOMIC_RELAXED);
if (id >= (UINTPTR_MAX - (uintptr_t)__ld_percpu_start) / stride)
return nullptr;
phys_t mem;
if (mem_phys_alloc(stride / pgsz, 0, &mem))
return nullptr;
const uintptr_t base = (uintptr_t)percpu_cpu(id);
for (size_t offset = 0; offset < stride; offset += pgsz) {
if (pmap_map(&kernel_vma.pmap, base + offset, mem + offset, PTE_READ | PTE_WRITE, CACHE_ANY)) {
while (offset) {
offset -= pgsz;
pmap_unmap(&kernel_vma.pmap, base + offset);
}
mem_phys_free(mem, stride / pgsz);
return nullptr;
}
}
struct percpu* cpu = (struct percpu*)base;
cpu->self = cpu;
cpu->id = id;
cpu->online = false;
atomic_store(&num_cpus, id + 1, ATOMIC_RELEASE);
return cpu;
}
size_t percpu_max_cpus() {
return max_cpus;
}
size_t percpu_count() {
return atomic_load(&num_cpus, ATOMIC_RELAXED);
}
struct percpu* percpu_get() {
return arch_percpu_get();
}
void percpu_bsp_init() {
arch_percpu_bsp_init();
}
void percpu_init(struct boot_info*) {
arch_percpu_init();
}
INIT_TASK(percpu_stage, "core.percpu", percpu_init);
INIT_DEPENDS(percpu_stage, mem_stage);