Beispiel #1
0
void fpsimd_flush_thread(void)
{
	preempt_disable();
	memset(&current->thread.fpsimd_state, 0, sizeof(struct fpsimd_state));
	fpsimd_load_state(&current->thread.fpsimd_state);
	preempt_enable();
}
Beispiel #2
0
void kernel_neon_end(void)
{
	if (current->mm)
		fpsimd_load_state(&current->thread.fpsimd_state);

	preempt_enable();
}
Beispiel #3
0
static int restore_fpsimd_context(struct fpsimd_context __user *ctx)
{
	struct fpsimd_state fpsimd;
	__u32 magic, size;
	int err = 0;

	/* check the magic/size information */
	__get_user_error(magic, &ctx->head.magic, err);
	__get_user_error(size, &ctx->head.size, err);
	if (err)
		return -EFAULT;
	if (magic != FPSIMD_MAGIC || size != sizeof(struct fpsimd_context))
		return -EINVAL;

	/* copy the FP and status/control registers */
	err = __copy_from_user(fpsimd.vregs, ctx->vregs,
			       sizeof(fpsimd.vregs));
	__get_user_error(fpsimd.fpsr, &ctx->fpsr, err);
	__get_user_error(fpsimd.fpcr, &ctx->fpcr, err);

	/* load the hardware registers from the fpsimd_state structure */
	if (!err) {
		preempt_disable();
		fpsimd_load_state(&fpsimd);
		preempt_enable();
	}

	return err ? -EFAULT : 0;
}
Beispiel #4
0
void fpsimd_thread_switch(struct task_struct *next)
{
	/* check if not kernel threads */
	if (current->mm)
		fpsimd_save_state(&current->thread.fpsimd_state);
	if (next->mm)
		fpsimd_load_state(&next->thread.fpsimd_state);
}
Beispiel #5
0
/*
 * Update current's FPSIMD/SVE registers from thread_struct.
 *
 * This function should be called only when the FPSIMD/SVE state in
 * thread_struct is known to be up to date, when preparing to enter
 * userspace.
 *
 * Softirqs (and preemption) must be disabled.
 */
static void task_fpsimd_load(void)
{
	WARN_ON(!in_softirq() && !irqs_disabled());

	if (system_supports_sve() && test_thread_flag(TIF_SVE))
		sve_load_state(sve_pffr(&current->thread),
			       &current->thread.uw.fpsimd_state.fpsr,
			       sve_vq_from_vl(current->thread.sve_vl) - 1);
	else
		fpsimd_load_state(&current->thread.uw.fpsimd_state);
}
Beispiel #6
0
/*
 * Load an updated userland FPSIMD state for 'current' from memory and set the
 * flag that indicates that the FPSIMD register contents are the most recent
 * FPSIMD state of 'current'
 */
void fpsimd_update_current_state(struct fpsimd_state *state)
{
	preempt_disable();
	fpsimd_load_state(state);
	if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) {
		struct fpsimd_state *st = &current->thread.fpsimd_state;

		this_cpu_write(fpsimd_last_state, st);
		st->cpu = smp_processor_id();
	}
	preempt_enable();
}
Beispiel #7
0
void kernel_neon_end(void)
{
	if (in_interrupt()) {
		struct fpsimd_partial_state *s = this_cpu_ptr(
			in_irq() ? &hardirq_fpsimdstate : &softirq_fpsimdstate);
		fpsimd_load_partial_state(s);
	} else {
		if (current->mm)
			fpsimd_load_state(&current->thread.fpsimd_state);
		preempt_enable();
	}
}
Beispiel #8
0
/*
 * Load the userland FPSIMD state of 'current' from memory, but only if the
 * FPSIMD state already held in the registers is /not/ the most recent FPSIMD
 * state of 'current'
 */
void fpsimd_restore_current_state(void)
{
	if (!system_supports_fpsimd())
		return;
	preempt_disable();
	if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) {
		struct fpsimd_state *st = &current->thread.fpsimd_state;

		fpsimd_load_state(st);
		this_cpu_write(fpsimd_last_state, st);
		st->cpu = smp_processor_id();
	}
	preempt_enable();
}
Beispiel #9
0
static int fpsimd_cpu_pm_notifier(struct notifier_block *self,
				  unsigned long cmd, void *v)
{
	switch (cmd) {
	case CPU_PM_ENTER:
		if (current->mm)
			fpsimd_save_state(&current->thread.fpsimd_state);
		break;
	case CPU_PM_EXIT:
		if (current->mm)
			fpsimd_load_state(&current->thread.fpsimd_state);
		break;
	case CPU_PM_ENTER_FAILED:
	default:
		return NOTIFY_DONE;
	}
	return NOTIFY_OK;
}