Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/nds32/kernel/process.c b/arch/nds32/kernel/process.c
index 65fda98..9712fd4 100644
--- a/arch/nds32/kernel/process.c
+++ b/arch/nds32/kernel/process.c
@@ -9,15 +9,16 @@
#include <linux/uaccess.h>
#include <asm/elf.h>
#include <asm/proc-fns.h>
+#include <asm/fpu.h>
#include <linux/ptrace.h>
#include <linux/reboot.h>
-extern void setup_mm_for_reboot(char mode);
-#ifdef CONFIG_PROC_FS
-struct proc_dir_entry *proc_dir_cpu;
-EXPORT_SYMBOL(proc_dir_cpu);
+#if IS_ENABLED(CONFIG_LAZY_FPU)
+struct task_struct *last_task_used_math;
#endif
+extern void setup_mm_for_reboot(char mode);
+
extern inline void arch_reset(char mode)
{
if (mode == 's') {
@@ -120,20 +121,36 @@
regs->uregs[3], regs->uregs[2], regs->uregs[1], regs->uregs[0]);
pr_info(" IRQs o%s Segment %s\n",
interrupts_enabled(regs) ? "n" : "ff",
- segment_eq(get_fs(), get_ds())? "kernel" : "user");
+ segment_eq(get_fs(), KERNEL_DS)? "kernel" : "user");
}
EXPORT_SYMBOL(show_regs);
+void exit_thread(struct task_struct *tsk)
+{
+#if defined(CONFIG_FPU) && defined(CONFIG_LAZY_FPU)
+ if (last_task_used_math == tsk)
+ last_task_used_math = NULL;
+#endif
+}
+
void flush_thread(void)
{
+#if defined(CONFIG_FPU)
+ clear_fpu(task_pt_regs(current));
+ clear_used_math();
+# ifdef CONFIG_LAZY_FPU
+ if (last_task_used_math == current)
+ last_task_used_math = NULL;
+# endif
+#endif
}
DEFINE_PER_CPU(struct task_struct *, __entry_task);
asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
int copy_thread(unsigned long clone_flags, unsigned long stack_start,
- unsigned long stk_sz, struct task_struct *p)
+ unsigned long stk_sz, struct task_struct *p)
{
struct pt_regs *childregs = task_pt_regs(p);
@@ -159,6 +176,22 @@
p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
p->thread.cpu_context.sp = (unsigned long)childregs;
+#if IS_ENABLED(CONFIG_FPU)
+ if (used_math()) {
+# if !IS_ENABLED(CONFIG_LAZY_FPU)
+ unlazy_fpu(current);
+# else
+ preempt_disable();
+ if (last_task_used_math == current)
+ save_fpu(current);
+ preempt_enable();
+# endif
+ p->thread.fpu = current->thread.fpu;
+ clear_fpu(task_pt_regs(p));
+ set_stopped_child_used_math(p);
+ }
+#endif
+
#ifdef CONFIG_HWZOL
childregs->lb = 0;
childregs->le = 0;
@@ -168,12 +201,33 @@
return 0;
}
+#if IS_ENABLED(CONFIG_FPU)
+struct task_struct *_switch_fpu(struct task_struct *prev, struct task_struct *next)
+{
+#if !IS_ENABLED(CONFIG_LAZY_FPU)
+ unlazy_fpu(prev);
+#endif
+ if (!(next->flags & PF_KTHREAD))
+ clear_fpu(task_pt_regs(next));
+ return prev;
+}
+#endif
+
/*
* fill in the fpe structure for a core dump...
*/
int dump_fpu(struct pt_regs *regs, elf_fpregset_t * fpu)
{
int fpvalid = 0;
+#if IS_ENABLED(CONFIG_FPU)
+ struct task_struct *tsk = current;
+
+ fpvalid = tsk_used_math(tsk);
+ if (fpvalid) {
+ lose_fpu();
+ memcpy(fpu, &tsk->thread.fpu, sizeof(*fpu));
+ }
+#endif
return fpvalid;
}