Compare commits

..

3 Commits

Author SHA1 Message Date
Bananymous b0ff2392a1 Kernel: Add some helpful debug prints
Log RIP when stack pointer is out of bounds.

Log all syscalls that return ENOTSUP
2024-01-03 02:08:01 +02:00
Bananymous 001e95f973 Kernel: Optimize sse saving/loading
Only save and load sse when new thread is trying to execute sse
instruction. There is no need to do that every time we enter kernel.
2024-01-03 02:06:49 +02:00
Bananymous db0650cf10 LibC: Implement basic atexit. This allows clean exit from doom (soon) 2024-01-03 00:30:37 +02:00
6 changed files with 78 additions and 29 deletions

View File

@ -189,6 +189,7 @@ namespace Kernel::IDT
else
{
derrorln("Stack pointer out of bounds!");
derrorln("rip {H}", interrupt_stack.rip);
derrorln("rsp {H}, stack {H}->{H}, istack {H}->{H}",
interrupt_stack.rsp,
stack.vaddr(), stack.vaddr() + stack.size(),
@ -218,6 +219,23 @@ namespace Kernel::IDT
}
}
}
#if __enable_sse
else if (isr == ISR::DeviceNotAvailable)
{
asm volatile(
"movq %cr0, %rax;"
"andq $~(1 << 3), %rax;"
"movq %rax, %cr0;"
);
if (auto* current = &Thread::current(); current != Thread::sse_thread())
{
if (auto* sse = Thread::sse_thread())
sse->save_sse();
current->load_sse();
}
goto done;
}
#endif
}
if (PageTable::current().get_page_flags(interrupt_stack.rip & PAGE_ADDR_MASK) & PageTable::Flags::Present)
@ -259,7 +277,6 @@ namespace Kernel::IDT
int signal = 0;
switch (isr)
{
case ISR::DeviceNotAvailable:
case ISR::DivisionError:
case ISR::SIMDFloatingPointException:
case ISR::x87FloatingPointException:
@ -290,22 +307,11 @@ namespace Kernel::IDT
ASSERT(Thread::current().state() != Thread::State::Terminated);
done:
#if __enable_sse
if (from_userspace)
{
ASSERT(Thread::current().state() == Thread::State::Executing);
Thread::current().load_sse();
}
#endif
return;
}
extern "C" void cpp_irq_handler(uint64_t irq, InterruptStack& interrupt_stack)
{
#if __enable_sse
Thread::current().save_sse();
#endif
if (Scheduler::current_tid())
{
Thread::current().set_return_rsp(interrupt_stack.rsp);
@ -326,10 +332,6 @@ done:
Scheduler::get().reschedule_if_idling();
ASSERT(Thread::current().state() != Thread::State::Terminated);
#if __enable_sse
Thread::current().load_sse();
#endif
}
static void flush_idt()

View File

@ -75,7 +75,7 @@ namespace Kernel
vaddr_t interrupt_stack_base() const { return m_interrupt_stack ? m_interrupt_stack->vaddr() : 0; }
size_t interrupt_stack_size() const { return m_interrupt_stack ? m_interrupt_stack->size() : 0; }
static Thread& current() ;
static Thread& current();
static pid_t current_tid();
Process& process();
@ -87,8 +87,9 @@ namespace Kernel
size_t physical_page_count() const { return virtual_page_count(); }
#if __enable_sse
void save_sse() { asm volatile("fxsave %0" :: "m"(m_sse_storage)); }
void load_sse() { asm volatile("fxrstor %0" :: "m"(m_sse_storage)); }
void save_sse();
void load_sse();
static Thread* sse_thread();
#endif
private:

View File

@ -231,6 +231,17 @@ namespace Kernel
Thread* current = &current_thread();
#if __enable_sse
if (current != Thread::sse_thread())
{
asm volatile(
"movq %cr0, %rax;"
"orq $(1 << 3), %rax;"
"movq %rax, %cr0"
);
}
#endif
while (current->state() == Thread::State::Terminated)
{
Thread* thread = m_current_thread->thread;

View File

@ -26,10 +26,6 @@ namespace Kernel
Thread::current().set_return_rsp(interrupt_stack.rsp);
Thread::current().set_return_rip(interrupt_stack.rip);
#if __enable_sse
Thread::current().save_sse();
#endif
asm volatile("sti");
(void)arg1;
@ -221,6 +217,9 @@ namespace Kernel
asm volatile("cli");
if (ret.is_error() && ret.error().get_error_code() == ENOTSUP)
dprintln("ENOTSUP {}", syscall);
if (ret.is_error() && ret.error().is_kernel_error())
Kernel::panic("Kernel error while returning to userspace {}", ret.error());
@ -230,10 +229,6 @@ namespace Kernel
ASSERT(Kernel::Thread::current().state() == Kernel::Thread::State::Executing);
#if __enable_sse
current_thread.load_sse();
#endif
if (ret.is_error())
return -ret.error().get_error_code();
return ret.value();

View File

@ -101,7 +101,16 @@ namespace Kernel
: m_tid(tid), m_process(process)
{
#if __enable_sse
uintptr_t cr0;
asm volatile(
"movq %%cr0, %%rax;"
"movq %%rax, %%rbx;"
"andq $~(1 << 3), %%rax;"
"movq %%rax, %%cr0;"
: "=b"(cr0)
);
save_sse();
asm volatile("movq %0, %%cr0" :: "r"(cr0));
#endif
}
@ -361,4 +370,24 @@ namespace Kernel
ASSERT_NOT_REACHED();
}
#if __enable_sse
static Thread* s_sse_thread = nullptr;
void Thread::save_sse()
{
asm volatile("fxsave %0" :: "m"(m_sse_storage));
}
void Thread::load_sse()
{
asm volatile("fxrstor %0" :: "m"(m_sse_storage));
s_sse_thread = this;
}
Thread* Thread::sse_thread()
{
return s_sse_thread;
}
#endif
}

View File

@ -13,6 +13,9 @@ extern "C" char** environ;
extern "C" void _fini();
static void (*at_exit_funcs[64])();
static uint32_t at_exit_funcs_count = 0;
void abort(void)
{
fflush(nullptr);
@ -22,6 +25,8 @@ void abort(void)
void exit(int status)
{
for (uint32_t i = at_exit_funcs_count; i > 0; i--)
at_exit_funcs[i - 1]();
fflush(nullptr);
__cxa_finalize(nullptr);
_fini();
@ -34,9 +39,15 @@ int abs(int val)
return val < 0 ? -val : val;
}
int atexit(void(*)(void))
int atexit(void (*func)(void))
{
return -1;
if (at_exit_funcs_count > sizeof(at_exit_funcs) / sizeof(*at_exit_funcs))
{
errno = ENOBUFS;
return -1;
}
at_exit_funcs[at_exit_funcs_count++] = func;
return 0;
}
int atoi(const char* str)