foo

core/percpu.c

@@ -1,6 +1,22 @@
+#include <zinnia/alloc.h>
+#include <zinnia/cmdline.h>
 #include <zinnia/compiler.h>
 #include <zinnia/percpu.h>
+#include <zinnia/string.h>
+#include <zinnia/utils.h>
 #include <arch/percpu.h>
+#include <stdatomic.h>
+
+extern uint8_t __ld_percpu_start[];
+extern uint8_t __ld_percpu_end[];
+
+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 = {
@@ -10,8 +26,22 @@ struct percpu percpu_bsp = {
 };
 
 struct percpu* percpu_new() {
-    // TODO
-    return nullptr;
+    const size_t size = __ld_percpu_end - __ld_percpu_start;
+    const size_t num_pages = ALIGN_UP(size, arch_mem_page_size()) / arch_mem_page_size();
+
+    phys_t mem;
+    if (mem_phys_alloc(num_pages, 0, &mem))
+        return nullptr;
+
+    struct percpu* cpu = HHDM_PTR(mem);
+    cpu->self = cpu;
+    cpu->id = atomic_fetch_add_explicit(&num_cpus, 1, memory_order_relaxed);
+    cpu->online = false;
+    return cpu;
+}
+
+size_t percpu_max_cpus() {
+    return max_cpus;
 }
 
 struct percpu* percpu_get() {