From 1cc22e78e28b20f078a1179a93a8d7aea4ebcd0e Mon Sep 17 00:00:00 2001
From: "Justin C. Miller" <justin@devjustinian.com>
Date: Sun, 13 Mar 2022 17:40:19 -0700
Subject: [PATCH] [kernel] Save all cpu_data pointers in global array

For the sake of introspection and debugging, I created a new g_cpu_data
pointer, which points to an array of cpu_data pointers.
---
 src/kernel/cpu.cpp | 2 ++
 src/kernel/smp.cpp | 6 +++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/kernel/cpu.cpp b/src/kernel/cpu.cpp
index 1433f12..9e9a158 100644
--- a/src/kernel/cpu.cpp
+++ b/src/kernel/cpu.cpp
@@ -22,6 +22,7 @@ panic_data g_panic_data;
 panic_data *g_panic_data_p = &g_panic_data;
 
 cpu_data g_bsp_cpu_data;
+cpu_data **g_cpu_data = nullptr;
 
 
 // Validate the required CPU features are present. Really, the bootloader already
@@ -115,6 +116,7 @@ cpu_create(uint16_t id, uint16_t index)
     GDT *gdt = new GDT {tss};
     cpu_data *cpu = new cpu_data;
     memset(cpu, 0, sizeof(cpu_data));
+    g_cpu_data[index] = cpu;
 
     cpu->self = cpu;
     cpu->id = id;
diff --git a/src/kernel/smp.cpp b/src/kernel/smp.cpp
index 7a54159..b086203 100644
--- a/src/kernel/smp.cpp
+++ b/src/kernel/smp.cpp
@@ -22,6 +22,8 @@ extern size_t ap_startup_code_size;
 extern obj::process &g_kernel_process;
 extern obj::vm_area_guarded &g_kernel_stacks;
 
+extern cpu_data **g_cpu_data;
+
 namespace smp {
 
 volatile size_t ap_startup_count;
@@ -35,13 +37,15 @@ start(cpu_data &bsp, void *kpml4)
     using mem::kernel_stack_pages;
     using obj::vm_flags;
 
-
     ap_startup_count = 1; // Count the BSP
 
     clock &clk = clock::get();
 
     const auto &ids = device_manager::get().get_apic_ids();
 
+    g_cpu_data = new cpu_data* [ids.count()];
+    g_cpu_data[bsp.index] = &bsp;
+
     log::info(logs::boot, "Starting %d other CPUs", ids.count() - 1);
 
     // Since we're using address space outside kernel space, make sure