sparc64: Implement HAVE_CONTEXT_TRACKING

Mark the places when the system are in user or are in kernel.
This is used to make full dynticks system (tickless) --
CONFIG_NO_HZ_FULL dependence.
Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
CC: David Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/Kconfig

@@ -64,6 +64,7 @@ config SPARC64
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_SYSCALL_TRACEPOINTS
+	select HAVE_CONTEXT_TRACKING
 	select HAVE_DEBUG_KMEMLEAK
 	select RTC_DRV_CMOS
 	select RTC_DRV_BQ4802

arch/sparc/include/asm/thread_info_64.h

@@ -192,7 +192,7 @@ register struct thread_info *current_thread_info_reg asm("g6");
 #define TIF_UNALIGNED		5	/* allowed to do unaligned accesses */
 /* flag bit 6 is available */
 #define TIF_32BIT		7	/* 32-bit binary */
-/* flag bit 8 is available */
+#define TIF_NOHZ		8	/* in adaptive nohz mode */
 #define TIF_SECCOMP		9	/* secure computing */
 #define TIF_SYSCALL_AUDIT	10	/* syscall auditing active */
 #define TIF_SYSCALL_TRACEPOINT	11	/* syscall tracepoint instrumentation */
@@ -210,6 +210,7 @@ register struct thread_info *current_thread_info_reg asm("g6");
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_UNALIGNED		(1<<TIF_UNALIGNED)
 #define _TIF_32BIT		(1<<TIF_32BIT)
+#define _TIF_NOHZ		(1<<TIF_NOHZ)
 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
 #define _TIF_SYSCALL_TRACEPOINT	(1<<TIF_SYSCALL_TRACEPOINT)

arch/sparc/kernel/entry.h

@@ -88,7 +88,6 @@ extern asmlinkage void syscall_trace_leave(struct pt_regs *regs);
 
 extern void bad_trap_tl1(struct pt_regs *regs, long lvl);
 
-extern void do_fpe_common(struct pt_regs *regs);
 extern void do_fpieee(struct pt_regs *regs);
 extern void do_fpother(struct pt_regs *regs);
 extern void do_tof(struct pt_regs *regs);

arch/sparc/kernel/kgdb_64.c

@@ -159,11 +159,12 @@ int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
 
 asmlinkage void kgdb_trap(unsigned long trap_level, struct pt_regs *regs)
 {
+	enum ctx_state prev_state = exception_enter();
 	unsigned long flags;
 
 	if (user_mode(regs)) {
 		bad_trap(regs, trap_level);
-		return;
+		goto out;
 	}
 
 	flushw_all();
@@ -171,6 +172,8 @@ asmlinkage void kgdb_trap(unsigned long trap_level, struct pt_regs *regs)
 	local_irq_save(flags);
 	kgdb_handle_exception(0x172, SIGTRAP, 0, regs);
 	local_irq_restore(flags);
+out:
+	exception_exit(prev_state);
 }
 
 int kgdb_arch_init(void)

arch/sparc/kernel/kprobes.c

@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/kdebug.h>
 #include <linux/slab.h>
+#include <linux/context_tracking.h>
 #include <asm/signal.h>
 #include <asm/cacheflush.h>
 #include <asm/uaccess.h>
@@ -418,12 +419,14 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
 asmlinkage void __kprobes kprobe_trap(unsigned long trap_level,
 				      struct pt_regs *regs)
 {
+	enum ctx_state prev_state = exception_enter();
+
 	BUG_ON(trap_level != 0x170 && trap_level != 0x171);
 
 	if (user_mode(regs)) {
 		local_irq_enable();
 		bad_trap(regs, trap_level);
-		return;
+		goto out;
 	}
 
 	/* trap_level == 0x170 --> ta 0x70
@@ -433,6 +436,8 @@ asmlinkage void __kprobes kprobe_trap(unsigned long trap_level,
 		       (trap_level == 0x170) ? "debug" : "debug_2",
 		       regs, 0, trap_level, SIGTRAP) != NOTIFY_STOP)
 		bad_trap(regs, trap_level);
+out:
+	exception_exit(prev_state);
 }
 
 /* Jprobes support.  */

arch/sparc/kernel/process_64.c

@@ -31,6 +31,7 @@
 #include <linux/elfcore.h>
 #include <linux/sysrq.h>
 #include <linux/nmi.h>
+#include <linux/context_tracking.h>
 
 #include <asm/uaccess.h>
 #include <asm/page.h>
@@ -557,6 +558,7 @@ void fault_in_user_windows(void)
 
 barf:
 	set_thread_wsaved(window + 1);
+	user_exit();
 	do_exit(SIGILL);
 }
 

arch/sparc/kernel/ptrace_64.c

@@ -27,6 +27,7 @@
 #include <trace/syscall.h>
 #include <linux/compat.h>
 #include <linux/elf.h>
+#include <linux/context_tracking.h>
 
 #include <asm/asi.h>
 #include <asm/pgtable.h>
@@ -1066,6 +1067,9 @@ asmlinkage int syscall_trace_enter(struct pt_regs *regs)
 	/* do the secure computing check first */
 	secure_computing_strict(regs->u_regs[UREG_G1]);
 
+	if (test_thread_flag(TIF_NOHZ))
+		user_exit();
+
 	if (test_thread_flag(TIF_SYSCALL_TRACE))
 		ret = tracehook_report_syscall_entry(regs);
 
@@ -1086,6 +1090,9 @@ asmlinkage int syscall_trace_enter(struct pt_regs *regs)
 
 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 {
+	if (test_thread_flag(TIF_NOHZ))
+		user_exit();
+
 	audit_syscall_exit(regs);
 
 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
@@ -1093,4 +1100,7 @@ asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 
 	if (test_thread_flag(TIF_SYSCALL_TRACE))
 		tracehook_report_syscall_exit(regs, 0);
+
+	if (test_thread_flag(TIF_NOHZ))
+		user_enter();
 }

arch/sparc/kernel/rtrap_64.S

@@ -18,10 +18,16 @@
 #define		RTRAP_PSTATE_IRQOFF	(PSTATE_TSO|PSTATE_PEF|PSTATE_PRIV)
 #define		RTRAP_PSTATE_AG_IRQOFF	(PSTATE_TSO|PSTATE_PEF|PSTATE_PRIV|PSTATE_AG)
 
+#ifdef CONFIG_CONTEXT_TRACKING
+# define SCHEDULE_USER schedule_user
+#else
+# define SCHEDULE_USER schedule
+#endif
+
 		.text
 		.align			32
 __handle_preemption:
-		call			schedule
+		call			SCHEDULE_USER
 		 wrpr			%g0, RTRAP_PSTATE, %pstate
 		ba,pt			%xcc, __handle_preemption_continue
 		 wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate

arch/sparc/kernel/signal_64.c

@@ -23,6 +23,7 @@
 #include <linux/tty.h>
 #include <linux/binfmts.h>
 #include <linux/bitops.h>
+#include <linux/context_tracking.h>
 
 #include <asm/uaccess.h>
 #include <asm/ptrace.h>
@@ -43,6 +44,7 @@ asmlinkage void sparc64_set_context(struct pt_regs *regs)
 {
 	struct ucontext __user *ucp = (struct ucontext __user *)
 		regs->u_regs[UREG_I0];
+	enum ctx_state prev_state = exception_enter();
 	mc_gregset_t __user *grp;
 	unsigned long pc, npc, tstate;
 	unsigned long fp, i7;
@@ -129,16 +131,19 @@ asmlinkage void sparc64_set_context(struct pt_regs *regs)
 	}
 	if (err)
 		goto do_sigsegv;
-
+out:
+	exception_exit(prev_state);
 	return;
 do_sigsegv:
 	force_sig(SIGSEGV, current);
+	goto out;
 }
 
 asmlinkage void sparc64_get_context(struct pt_regs *regs)
 {
 	struct ucontext __user *ucp = (struct ucontext __user *)
 		regs->u_regs[UREG_I0];
+	enum ctx_state prev_state = exception_enter();
 	mc_gregset_t __user *grp;
 	mcontext_t __user *mcp;
 	unsigned long fp, i7;
@@ -220,10 +225,12 @@ asmlinkage void sparc64_get_context(struct pt_regs *regs)
 	}
 	if (err)
 		goto do_sigsegv;
-
+out:
+	exception_exit(prev_state);
 	return;
 do_sigsegv:
 	force_sig(SIGSEGV, current);
+	goto out;
 }
 
 struct rt_signal_frame {
@@ -528,11 +535,13 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
 
 void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
 {
+	user_exit();
 	if (thread_info_flags & _TIF_SIGPENDING)
 		do_signal(regs, orig_i0);
 	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
 		clear_thread_flag(TIF_NOTIFY_RESUME);
 		tracehook_notify_resume(regs);
 	}
+	user_enter();
 }
 

arch/sparc/kernel/sys_sparc_64.c

@@ -24,6 +24,7 @@
 #include <linux/personality.h>
 #include <linux/random.h>
 #include <linux/export.h>
+#include <linux/context_tracking.h>
 
 #include <asm/uaccess.h>
 #include <asm/utrap.h>
@@ -496,6 +497,7 @@ asmlinkage unsigned long c_sys_nis_syscall(struct pt_regs *regs)
 
 asmlinkage void sparc_breakpoint(struct pt_regs *regs)
 {
+	enum ctx_state prev_state = exception_enter();
 	siginfo_t info;
 
 	if (test_thread_flag(TIF_32BIT)) {
@@ -514,6 +516,7 @@ asmlinkage void sparc_breakpoint(struct pt_regs *regs)
 #ifdef DEBUG_SPARC_BREAKPOINT
 	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
 #endif
+	exception_exit(prev_state);
 }
 
 extern void check_pending(int signum);

arch/sparc/kernel/syscalls.S

@@ -52,7 +52,7 @@ sys32_rt_sigreturn:
 #endif
 	.align	32
 1:	ldx	[%g6 + TI_FLAGS], %l5
-	andcc	%l5, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
+	andcc	%l5, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
 	be,pt	%icc, rtrap
 	 nop
 	call	syscall_trace_leave
@@ -184,7 +184,7 @@ linux_sparc_syscall32:
 
 	srl	%i3, 0, %o3				! IEU0
 	srl	%i2, 0, %o2				! IEU0	Group
-	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
+	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
 	bne,pn	%icc, linux_syscall_trace32		! CTI
 	 mov	%i0, %l5				! IEU1
 5:	call	%l7					! CTI	Group brk forced
@@ -207,7 +207,7 @@ linux_sparc_syscall:
 
 	mov	%i3, %o3				! IEU1
 	mov	%i4, %o4				! IEU0	Group
-	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
+	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
 	bne,pn	%icc, linux_syscall_trace		! CTI	Group
 	 mov	%i0, %l5				! IEU0
 2:	call	%l7					! CTI	Group brk forced
@@ -223,7 +223,7 @@ ret_sys_call:
 
 	cmp	%o0, -ERESTART_RESTARTBLOCK
 	bgeu,pn	%xcc, 1f
-	 andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
+	 andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
 	ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
 
 2:

arch/sparc/kernel/unaligned_64.c

@@ -21,9 +21,12 @@
 #include <linux/bitops.h>
 #include <linux/perf_event.h>
 #include <linux/ratelimit.h>
+#include <linux/context_tracking.h>
 #include <asm/fpumacro.h>
 #include <asm/cacheflush.h>
 
+#include "entry.h"
+
 enum direction {
 	load,    /* ld, ldd, ldh, ldsh */
 	store,   /* st, std, sth, stsh */
@@ -418,9 +421,6 @@ int handle_popc(u32 insn, struct pt_regs *regs)
 
 extern void do_fpother(struct pt_regs *regs);
 extern void do_privact(struct pt_regs *regs);
-extern void spitfire_data_access_exception(struct pt_regs *regs,
-					   unsigned long sfsr,
-					   unsigned long sfar);
 extern void sun4v_data_access_exception(struct pt_regs *regs,
 					unsigned long addr,
 					unsigned long type_ctx);
@@ -578,6 +578,7 @@ void handle_ld_nf(u32 insn, struct pt_regs *regs)
 
 void handle_lddfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
 {
+	enum ctx_state prev_state = exception_enter();
 	unsigned long pc = regs->tpc;
 	unsigned long tstate = regs->tstate;
 	u32 insn;
@@ -632,13 +633,16 @@ void handle_lddfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr
 			sun4v_data_access_exception(regs, sfar, sfsr);
 		else
 			spitfire_data_access_exception(regs, sfsr, sfar);
-		return;
+		goto out;
 	}
 	advance(regs);
+out:
+	exception_exit(prev_state);
 }
 
 void handle_stdfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
 {
+	enum ctx_state prev_state = exception_enter();
 	unsigned long pc = regs->tpc;
 	unsigned long tstate = regs->tstate;
 	u32 insn;
@@ -680,7 +684,9 @@ void handle_stdfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr
 			sun4v_data_access_exception(regs, sfar, sfsr);
 		else
 			spitfire_data_access_exception(regs, sfsr, sfar);
-		return;
+		goto out;
 	}
 	advance(regs);
+out:
+	exception_exit(prev_state);
 }

arch/sparc/mm/fault_64.c

@@ -21,6 +21,7 @@
 #include <linux/kprobes.h>
 #include <linux/kdebug.h>
 #include <linux/percpu.h>
+#include <linux/context_tracking.h>
 
 #include <asm/page.h>
 #include <asm/pgtable.h>
@@ -272,6 +273,7 @@ static void noinline __kprobes bogus_32bit_fault_address(struct pt_regs *regs,
 
 asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 {
+	enum ctx_state prev_state = exception_enter();
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
 	unsigned int insn = 0;
@@ -282,7 +284,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 	fault_code = get_thread_fault_code();
 
 	if (notify_page_fault(regs))
-		return;
+		goto exit_exception;
 
 	si_code = SEGV_MAPERR;
 	address = current_thread_info()->fault_address;
@@ -313,7 +315,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 			/* Valid, no problems... */
 		} else {
 			bad_kernel_pc(regs, address);
-			return;
+			goto exit_exception;
 		}
 	} else
 		flags |= FAULT_FLAG_USER;
@@ -430,7 +432,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 	fault = handle_mm_fault(mm, vma, address, flags);
 
 	if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
-		return;
+		goto exit_exception;
 
 	if (unlikely(fault & VM_FAULT_ERROR)) {
 		if (fault & VM_FAULT_OOM)
@@ -482,6 +484,8 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 
 	}
 #endif
+exit_exception:
+	exception_exit(prev_state);
 	return;
 
 	/*
@@ -494,7 +498,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 
 handle_kernel_fault:
 	do_kernel_fault(regs, si_code, fault_code, insn, address);
-	return;
+	goto exit_exception;
 
 /*
  * We ran out of memory, or some other thing happened to us that made
@@ -505,7 +509,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 	up_read(&mm->mmap_sem);
 	if (!(regs->tstate & TSTATE_PRIV)) {
 		pagefault_out_of_memory();
-		return;
+		goto exit_exception;
 	}
 	goto handle_kernel_fault;