Split AST handling from trap() into ast() and get rid of T_ASTFLT

testing by krw@, and then many via snapshots

8 files changed, 51 insertions, 46 deletions

diff --git a/sys/arch/i386/i386/apicvec.s b/sys/arch/i386/i386/apicvec.s
index 6de0c7eebcf..237def059bf 100644
--- a/sys/arch/i386/i386/apicvec.s
+++ b/sys/arch/i386/i386/apicvec.s
@@ -1,4 +1,4 @@
-/* $OpenBSD: apicvec.s,v 1.29 2015/02/07 00:26:37 deraadt Exp $ */
+/* $OpenBSD: apicvec.s,v 1.30 2015/06/28 01:11:27 guenther Exp $ */
 /* $NetBSD: apicvec.s,v 1.1.2.2 2000/02/21 21:54:01 sommerfeld Exp $ */
 
 /*-
@@ -42,8 +42,7 @@
 #ifdef MULTIPROCESSOR
 	.globl	XINTR(ipi)
 XINTR(ipi):
-	pushl	$0
-	pushl	$T_ASTFLT
+	subl	$8,%esp			/* space for tf_{err,trapno} */
 	INTRENTRY
 	MAKE_FRAME
 	pushl	CPL
@@ -156,8 +155,7 @@ XINTR(ipi_reloadcr3):
 	 */
 	.globl	XINTR(ltimer)
 XINTR(ltimer):
-	pushl	$0
-	pushl	$T_ASTFLT
+	subl	$8,%esp			/* space for tf_{err,trapno} */
 	INTRENTRY
 	MAKE_FRAME
 	pushl	CPL
@@ -175,8 +173,7 @@ XINTR(ltimer):
 
 	.globl	XINTR(softclock), XINTR(softnet), XINTR(softtty)
 XINTR(softclock):
-	pushl	$0
-	pushl	$T_ASTFLT
+	subl	$8,%esp			/* space for tf_{err,trapno} */
 	INTRENTRY
 	MAKE_FRAME
 	pushl	CPL
@@ -198,8 +195,7 @@ XINTR(softclock):
 	jmp	_C_LABEL(Xdoreti)
 
 XINTR(softnet):
-	pushl	$0
-	pushl	$T_ASTFLT
+	subl	$8,%esp			/* space for tf_{err,trapno} */
 	INTRENTRY
 	MAKE_FRAME
 	pushl	CPL
@@ -222,8 +218,7 @@ XINTR(softnet):
 #undef DONETISR
 
 XINTR(softtty):
-	pushl	$0
-	pushl	$T_ASTFLT
+	subl	$8,%esp			/* space for tf_{err,trapno} */
 	INTRENTRY
 	MAKE_FRAME
 	pushl	CPL
@@ -258,8 +253,7 @@ XINTR(softtty):
 
 #define APICINTR(name, num, early_ack, late_ack, mask, unmask, level_mask) \
 _C_LABEL(Xintr_##name##num):						\
-	pushl	$0							;\
-	pushl	$T_ASTFLT						;\
+	subl	$8,%esp			/* space for tf_{err,trapno} */	;\
 	INTRENTRY							;\
 	MAKE_FRAME							;\
 	pushl	CPL							;\
diff --git a/sys/arch/i386/i386/db_trace.c b/sys/arch/i386/i386/db_trace.c
index 291b9e9cb0f..a8cf498e4cd 100644
--- a/sys/arch/i386/i386/db_trace.c
+++ b/sys/arch/i386/i386/db_trace.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: db_trace.c,v 1.14 2014/07/13 12:11:01 jasper Exp $	*/
+/*	$OpenBSD: db_trace.c,v 1.15 2015/06/28 01:11:27 guenther Exp $	*/
 /*	$NetBSD: db_trace.c,v 1.18 1996/05/03 19:42:01 christos Exp $	*/
 
 /*
@@ -78,6 +78,7 @@ struct i386_frame {
 #define	TRAP		1
 #define	SYSCALL		2
 #define	INTERRUPT	3
+#define	AST		4
 
 db_addr_t	db_trap_symbol_value = 0;
 db_addr_t	db_syscall_symbol_value = 0;
@@ -161,6 +162,9 @@ db_nextframe(struct i386_frame **fp, db_addr_t	*ip, int *argp, int is_trap,
 		case TRAP:
 			(*pr)("--- trap (number %d) ---\n", tf->tf_trapno);
 			break;
+		case AST:
+			(*pr)("--- ast ---\n");
+			break;
 		case SYSCALL:
 			(*pr)("--- syscall (number %d) ---\n", tf->tf_eax);
 			break;
@@ -256,6 +260,8 @@ db_stack_trace_print(db_expr_t addr, boolean_t have_addr, db_expr_t count,
 		if (INKERNEL((int)frame) && name) {
 			if (!strcmp(name, "trap")) {
 				is_trap = TRAP;
+			} else if (!strcmp(name, "ast")) {
+				is_trap = AST;
 			} else if (!strcmp(name, "syscall")) {
 				is_trap = SYSCALL;
 			} else if (!strncmp(name, "Xintr", 5) ||
diff --git a/sys/arch/i386/i386/kgdb_machdep.c b/sys/arch/i386/i386/kgdb_machdep.c
index 245f9bba3da..1a46515fd7c 100644
--- a/sys/arch/i386/i386/kgdb_machdep.c
+++ b/sys/arch/i386/i386/kgdb_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kgdb_machdep.c,v 1.12 2015/04/12 18:37:53 mlarkin Exp $	*/
+/*	$OpenBSD: kgdb_machdep.c,v 1.13 2015/06/28 01:11:27 guenther Exp $	*/
 /*	$NetBSD: kgdb_machdep.c,v 1.6 1998/08/13 21:36:03 thorpej Exp $	*/
 
 /*-
@@ -115,7 +115,6 @@ kgdb_signal(int type)
 	case T_TRCTRAP:
 		return (SIGTRAP);
 
-	case T_ASTFLT:
 	case T_DOUBLEFLT:
 		return (SIGEMT);
 
diff --git a/sys/arch/i386/i386/locore.s b/sys/arch/i386/i386/locore.s
index cea9a8437ba..9bd21dc7f53 100644
--- a/sys/arch/i386/i386/locore.s
+++ b/sys/arch/i386/i386/locore.s
@@ -1,4 +1,4 @@
-/*	$OpenBSD: locore.s,v 1.157 2015/04/26 09:48:29 kettenis Exp $	*/
+/*	$OpenBSD: locore.s,v 1.158 2015/06/28 01:11:27 guenther Exp $	*/
 /*	$NetBSD: locore.s,v 1.145 1996/05/03 19:41:19 christos Exp $	*/
 
 /*-
@@ -1408,8 +1408,7 @@ IDTVEC(fpu)
 	 * error.  It would be better to handle npx interrupts as traps but
 	 * this is difficult for nested interrupts.
 	 */
-	pushl	$0			# dummy error code
-	pushl	$T_ASTFLT
+	subl	$8,%esp			/* space for tf_{err,trapno} */
 	INTRENTRY
 	pushl	CPL			# if_ppl in intrframe
 	pushl	%esp			# push address of intrframe
@@ -1471,9 +1470,8 @@ calltrap:
 	jz	1f
 5:	CLEAR_ASTPENDING(%ecx)
 	sti
-	movl	$T_ASTFLT,TF_TRAPNO(%esp)
 	pushl	%esp
-	call	_C_LABEL(trap)
+	call	_C_LABEL(ast)
 	addl	$4,%esp
 	jmp	2b
 #ifndef DIAGNOSTIC
@@ -1498,8 +1496,7 @@ calltrap:
  * Trap gate entry for syscall
  */
 IDTVEC(syscall)
-	pushl	$2		# ignored
-	pushl	$T_ASTFLT	# trap # for doing ASTs
+	subl	$8,%esp			/* space for tf_{err,trapno} */
 	INTRENTRY
 	pushl	%esp
 	call	_C_LABEL(syscall)
@@ -1511,9 +1508,8 @@ IDTVEC(syscall)
 	/* Always returning to user mode here. */
 	CLEAR_ASTPENDING(%ecx)
 	sti
-	/* Pushed T_ASTFLT into tf_trapno on entry. */
 	pushl	%esp
-	call	_C_LABEL(trap)
+	call	_C_LABEL(ast)
 	addl	$4,%esp
 	jmp	2b
 1:	INTRFASTEXIT
diff --git a/sys/arch/i386/i386/trap.c b/sys/arch/i386/i386/trap.c
index 9843a2bac92..55f45f87a59 100644
--- a/sys/arch/i386/i386/trap.c
+++ b/sys/arch/i386/i386/trap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: trap.c,v 1.122 2015/04/24 12:52:38 kettenis Exp $	*/
+/*	$OpenBSD: trap.c,v 1.123 2015/06/28 01:11:27 guenther Exp $	*/
 /*	$NetBSD: trap.c,v 1.95 1996/05/05 06:50:02 mycroft Exp $	*/
 
 /*-
@@ -80,13 +80,14 @@ extern struct emul emul_linux_elf;
 #include "npx.h"
 
 void trap(struct trapframe *);
+void ast(struct trapframe *);
 void syscall(struct trapframe *);
 
 char	*trap_type[] = {
 	"privileged instruction fault",		/*  0 T_PRIVINFLT */
 	"breakpoint trap",			/*  1 T_BPTFLT */
 	"arithmetic trap",			/*  2 T_ARITHTRAP */
-	"asynchronous system trap",		/*  3 T_ASTFLT */
+	"reserved trap",			/*  3 T_RESERVED */
 	"protection fault",			/*  4 T_PROTFLT */
 	"trace trap",				/*  5 T_TRCTRAP */
 	"page fault",				/*  6 T_PAGEFLT */
@@ -103,7 +104,6 @@ char	*trap_type[] = {
 	"stack fault",				/* 17 T_STKFLT */
 	"machine check",			/* 18 T_MACHK ([P]Pro) */
 	"SIMD FP fault",			/* 19 T_XFTRAP */
-	"reserved trap",			/* 20 T_RESERVED */
 };
 int	trap_types = sizeof trap_type / sizeof trap_type[0];
 
@@ -118,7 +118,6 @@ int	trapdebug = 0;
  * routines that prepare a suitable stack frame, and restore this
  * frame after the exception has been processed.
  */
-/*ARGSUSED*/
 void
 trap(struct trapframe *frame)
 {
@@ -335,11 +334,6 @@ trap(struct trapframe *frame)
 		KERNEL_UNLOCK();
 		goto out;
 
-	case T_ASTFLT|T_USER:		/* Allow process switch */
-		uvmexp.softs++;
-		mi_ast(p, want_resched);
-		goto out;
-
 	case T_DNA|T_USER: {
 		printf("pid %d killed due to lack of floating point\n",
 		    p->p_pid);
@@ -522,6 +516,27 @@ out:
 	userret(p);
 }
 
+
+/*
+ * ast(frame):
+ *	AST handler.  This is called from assembly language stubs when
+ *	returning to userspace after a syscall, trap, or interrupt.
+ */
+void
+ast(struct trapframe *frame)
+{
+	struct proc *p = curproc;
+
+	uvmexp.traps++;
+	KASSERT(!KERNELMODE(frame->tf_cs, frame->tf_eflags));
+	p->p_md.md_regs = frame;
+	refreshcreds(p);
+	uvmexp.softs++;
+	mi_ast(p, want_resched);
+	userret(p);
+}
+
+
 /*
  * syscall(frame):
  *	System call request from POSIX system call gate interface to kernel.
diff --git a/sys/arch/i386/i386/vector.s b/sys/arch/i386/i386/vector.s
index 8f3aadff113..7ed63cf7fbe 100644
--- a/sys/arch/i386/i386/vector.s
+++ b/sys/arch/i386/i386/vector.s
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vector.s,v 1.19 2015/04/25 21:31:24 guenther Exp $	*/
+/*	$OpenBSD: vector.s,v 1.20 2015/06/28 01:11:27 guenther Exp $	*/
 /*	$NetBSD: vector.s,v 1.32 1996/01/07 21:29:47 mycroft Exp $	*/
 
 /*
@@ -80,8 +80,7 @@ IDTVEC(recurse_##name##num)						;\
 	pushfl								;\
 	pushl	%cs							;\
 	pushl	%esi							;\
-	pushl	$0			/* dummy error code */		;\
-	pushl	$T_ASTFLT		/* trap # for doing ASTs */	;\
+	subl	$8,%esp			/* space for tf_{err,trapno} */ ;\
 	movl	%ebx,%esi						;\
 	INTRENTRY							;\
 	MAKE_FRAME							;\
@@ -89,8 +88,7 @@ IDTVEC(recurse_##name##num)						;\
 	cli								;\
 	jmp	1f							;\
 _C_LABEL(Xintr_##name##num):						;\
-	pushl	$0			/* dummy error code */		;\
-	pushl	$T_ASTFLT		/* trap # for doing ASTs */	;\
+	subl	$8,%esp			/* space for tf_{err,trapno} */ ;\
 	INTRENTRY							;\
 	MAKE_FRAME							;\
 	mask(num)			/* mask it in hardware */	;\
diff --git a/sys/arch/i386/include/trap.h b/sys/arch/i386/include/trap.h
index 652bfbf9f1b..a93fee7c3ba 100644
--- a/sys/arch/i386/include/trap.h
+++ b/sys/arch/i386/include/trap.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: trap.h,v 1.5 2005/10/26 20:32:59 marco Exp $	*/
+/*	$OpenBSD: trap.h,v 1.6 2015/06/28 01:11:27 guenther Exp $	*/
 /*	$NetBSD: trap.h,v 1.4 1994/10/27 04:16:30 cgd Exp $	*/
 
 /*-
@@ -43,7 +43,7 @@
 #define	T_PRIVINFLT	 0	/* privileged instruction */
 #define	T_BPTFLT	 1	/* breakpoint trap */
 #define	T_ARITHTRAP	 2	/* arithmetic trap */
-#define	T_ASTFLT	 3	/* asynchronous system trap */
+#define	T_RESERVED	 3	/* reserved fault base */
 #define	T_PROTFLT	 4	/* protection fault */
 #define	T_TRCTRAP	 5	/* trace trap */
 #define	T_PAGEFLT	 6	/* page fault */
@@ -60,7 +60,6 @@
 #define	T_STKFLT	17	/* stack fault */
 #define	T_MACHK		18	/* machine check ([P]Pro) */
 #define	T_XFTRAP	19	/* SIMD FP exception */
-#define	T_RESERVED	20	/* reserved fault base */
 
 /* Trap's coming from user mode */
 #define	T_USER	0x100
diff --git a/sys/arch/i386/isa/icu.s b/sys/arch/i386/isa/icu.s
index 2d83f61843a..8b77101f110 100644
--- a/sys/arch/i386/isa/icu.s
+++ b/sys/arch/i386/isa/icu.s
@@ -1,4 +1,4 @@
-/*	$OpenBSD: icu.s,v 1.31 2010/12/21 14:56:23 claudio Exp $	*/
+/*	$OpenBSD: icu.s,v 1.32 2015/06/28 01:11:27 guenther Exp $	*/
 /*	$NetBSD: icu.s,v 1.45 1996/01/07 03:59:34 mycroft Exp $	*/
 
 /*-
@@ -103,10 +103,8 @@ IDTVEC(doreti)
 	jz	3f
 4:	CLEAR_ASTPENDING(%ecx)
 	sti
-	movl	$T_ASTFLT,TF_TRAPNO(%esp)	/* XXX undo later. */
-	/* Pushed T_ASTFLT into tf_trapno on entry. */
 	pushl	%esp
-	call	_C_LABEL(trap)
+	call	_C_LABEL(ast)
 	addl	$4,%esp
 	cli
 	jmp	2b