/*
* When this function is called with the following 'cmd's, the following
* is true while this function is being run:
* THREAD_NOFTIFY_SWTICH:
* - the previously running thread will not be scheduled onto another CPU.
* - the next thread to be run (v) will not be running on another CPU.
* - thread->cpu is the local CPU number
* - not preemptible as we're called in the middle of a thread switch
* THREAD_NOTIFY_FLUSH:
* - the thread (v) will be running on the local CPU, so
* v === current_thread_info()
* - thread->cpu is the local CPU number at the time it is accessed,
* but may change at any time.
* - we could be preempted if tree preempt rcu is enabled, so
* it is unsafe to use thread->cpu.
* THREAD_NOTIFY_EXIT
* - the thread (v) will be running on the local CPU, so
* v === current_thread_info()
* - thread->cpu is the local CPU number at the time it is accessed,
* but may change at any time.
* - we could be preempted if tree preempt rcu is enabled, so
* it is unsafe to use thread->cpu.
*/
static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v)
{
struct thread_info *thread = v;
u32 fpexc;
#ifdef CONFIG_SMP
unsigned int cpu;
#endif
switch (cmd) {
case THREAD_NOTIFY_SWITCH:
fpexc = fmrx(FPEXC);
#ifdef CONFIG_SMP
cpu = thread->cpu;
/*
* On SMP, if VFP is enabled, save the old state in
* case the thread migrates to a different CPU. The
* restoring is done lazily.
*/
if ((fpexc & FPEXC_EN) && vfp_current_hw_state[cpu]) {
vfp_save_state(vfp_current_hw_state[cpu], fpexc);
vfp_current_hw_state[cpu]->hard.cpu = cpu;
}
/*
* Thread migration, just force the reloading of the
* state on the new CPU in case the VFP registers
* contain stale data.
*/
if (thread->vfpstate.hard.cpu != cpu)
vfp_current_hw_state[cpu] = NULL;
#endif
/*
* Always disable VFP so we can lazily save/restore the
* old state.
*/
fmxr(FPEXC, fpexc & ~FPEXC_EN);
break;
case THREAD_NOTIFY_FLUSH:
vfp_thread_flush(thread);
break;
case THREAD_NOTIFY_EXIT:
vfp_thread_exit(thread);
break;
case THREAD_NOTIFY_COPY:
vfp_thread_copy(thread);
break;
}
return NOTIFY_DONE;
}
/*
* When this function is called with the following 'cmd's, the following
* is true while this function is being run:
* THREAD_NOFTIFY_SWTICH:
* - the previously running thread will not be scheduled onto another CPU.
* - the next thread to be run (v) will not be running on another CPU.
* - thread->cpu is the local CPU number
* - not preemptible as we're called in the middle of a thread switch
* THREAD_NOTIFY_FLUSH:
* - the thread (v) will be running on the local CPU, so
* v === current_thread_info()
* - thread->cpu is the local CPU number at the time it is accessed,
* but may change at any time.
* - we could be preempted if tree preempt rcu is enabled, so
* it is unsafe to use thread->cpu.
* THREAD_NOTIFY_EXIT
* - the thread (v) will be running on the local CPU, so
* v === current_thread_info()
* - thread->cpu is the local CPU number at the time it is accessed,
* but may change at any time.
* - we could be preempted if tree preempt rcu is enabled, so
* it is unsafe to use thread->cpu.
*/
static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v)
{
struct thread_info *thread = v;
u32 fpexc;
#ifdef CONFIG_SMP
unsigned int cpu;
#endif
switch (cmd) {
case THREAD_NOTIFY_SWITCH:
fpexc = fmrx(FPEXC);
#ifdef CONFIG_SMP
cpu = thread->cpu;
/*
* On SMP, if VFP is enabled, save the old state in
* case the thread migrates to a different CPU. The
* restoring is done lazily.
*/
if ((fpexc & FPEXC_EN) && vfp_current_hw_state[cpu])
vfp_save_state(vfp_current_hw_state[cpu], fpexc);
#endif
/*
* Always disable VFP so we can lazily save/restore the
* old state.
*/
fmxr(FPEXC, fpexc & ~FPEXC_EN);
break;
case THREAD_NOTIFY_FLUSH:
vfp_thread_flush(thread);
break;
case THREAD_NOTIFY_EXIT:
vfp_thread_exit(thread);
break;
// 2017-09-09
case THREAD_NOTIFY_COPY:
vfp_thread_copy(thread);
break;
}
return NOTIFY_DONE;
}
static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v)
{
struct thread_info *thread = v;
u32 fpexc;
#ifdef CONFIG_SMP
unsigned int cpu;
#endif
switch (cmd) {
case THREAD_NOTIFY_SWITCH:
fpexc = fmrx(FPEXC);
#ifdef CONFIG_SMP
cpu = thread->cpu;
if ((fpexc & FPEXC_EN) && vfp_current_hw_state[cpu])
vfp_save_state(vfp_current_hw_state[cpu], fpexc);
#endif
fmxr(FPEXC, fpexc & ~FPEXC_EN);
break;
case THREAD_NOTIFY_FLUSH:
vfp_thread_flush(thread);
break;
case THREAD_NOTIFY_EXIT:
vfp_thread_exit(thread);
break;
case THREAD_NOTIFY_COPY:
vfp_thread_copy(thread);
break;
}
return NOTIFY_DONE;
}