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| author | Aqua-sama <aqua@iserlohn-fortress.net> | 2021-03-06 17:51:05 +0200 |
|---|---|---|
| committer | Aqua-sama <aqua@iserlohn-fortress.net> | 2021-03-06 17:51:05 +0200 |
| commit | adfb2c00592e08815a546548f3e87809a645696c (patch) | |
| tree | 45b31744909ea1ebc0d75365bd0fdaac404fc145 | |
| parent | GDT: flush segment registers on lgdt (diff) | |
| download | kernel.cpp-adfb2c00592e08815a546548f3e87809a645696c.tar.xz | |
scheduler: fix task switching
| -rw-r--r-- | src/idt/stubs.S | 7 | ||||
| -rw-r--r-- | src/scheduler.cc | 25 | ||||
| -rw-r--r-- | src/scheduler.h | 2 |
3 files changed, 20 insertions, 14 deletions
diff --git a/src/idt/stubs.S b/src/idt/stubs.S index 4f1440d..d4fb56f 100644 --- a/src/idt/stubs.S +++ b/src/idt/stubs.S @@ -82,13 +82,14 @@ exception_common: iret interrupt_common: - pusha + pushal push %esp call handle_interrupt - add $4, %esp + #add $4, %esp + mov %eax, %esp - popa + popal /* remove error code and irq from stack */ add $8, %esp diff --git a/src/scheduler.cc b/src/scheduler.cc index 1557e28..4de9fff 100644 --- a/src/scheduler.cc +++ b/src/scheduler.cc @@ -9,20 +9,24 @@ void task_b(void) { while (true) printk("B"); } +constexpr uint16_t max_tasks = 256; +static cpu_state_t* tasks[max_tasks]; + static uint8_t stack_a[4096] = {0}; static uint8_t stack_b[4096] = {0}; -constexpr uint16_t max_tasks = 2; -static cpu_state_t* tasks[max_tasks]; Scheduler::Scheduler(uint16_t cs) : InterruptHandler(0x00) { - add_task(stack_a, cs, &task_a); - add_task(stack_b, cs, task_b); + printk("add_task: ", add_task(stack_b, cs, task_b), '\n'); + printk("add_task: ", add_task(stack_a, cs, task_a), '\n'); + + printk("task0 eip: ", uhex{tasks[0]->eip}, '\n'); + printk("task1 eip: ", uhex{tasks[1]->eip}, '\n'); } -bool Scheduler::add_task(uint8_t* stack, uint16_t cs, void (*entry)()) { - if (last_task_id == uint16_t_max) return false; +uint16_t Scheduler::add_task(uint8_t* stack, uint16_t cs, void (*entry)()) { + if (last_task_id == (max_tasks - 1)) return 0; - uint16_t id = last_task_id++; + uint16_t id = ++last_task_id; ++num_tasks; cpu_state_t* cpu_state = reinterpret_cast<cpu_state_t*>(stack + 4096 - sizeof(cpu_state_t)); @@ -33,14 +37,15 @@ bool Scheduler::add_task(uint8_t* stack, uint16_t cs, void (*entry)()) { tasks[id] = cpu_state; printk("adding task: cs ", uhex{cpu_state->cs}, " stack ", uhex{reinterpret_cast<uint32_t>(tasks[id])}, " entry ", uhex{cpu_state->eip}, '\n'); - return true; + return id; } cpu_state_t* Scheduler::trigger(cpu_state_t* cpu) { tasks[current_task] = cpu; - if (++current_task >= num_tasks) current_task %= num_tasks; + current_task++; + if (current_task > num_tasks) current_task = 0; - // printk("swapped to task ", current_task, '\n'); + printk("\n\nswapped to task ", current_task, '\n'); return tasks[current_task]; } diff --git a/src/scheduler.h b/src/scheduler.h index 9e5e9f2..a3148bb 100644 --- a/src/scheduler.h +++ b/src/scheduler.h @@ -7,7 +7,7 @@ class Scheduler : public InterruptHandler { public: Scheduler(uint16_t cs); - bool add_task(uint8_t* stack, uint16_t cs, void (*entry)()); + [[nodiscard]] uint16_t add_task(uint8_t* stack, uint16_t cs, void (*entry)()); [[nodiscard]] cpu_state_t* trigger(cpu_state_t*) override; private: |