Module Name: src
Committed By: reinoud
Date: Sat Jan 14 21:45:29 UTC 2012
Modified Files:
src/sys/arch/usermode/dev: cpu.c
src/sys/arch/usermode/usermode: syscall.c trap.c
Log Message:
Reimplement userret() to also include AST for preemption.
Note it would be nice if we could do the check "are we going to userland?" in
a less intrusive way.
To generate a diff of this commit:
cvs rdiff -u -r1.64 -r1.65 src/sys/arch/usermode/dev/cpu.c
cvs rdiff -u -r1.21 -r1.22 src/sys/arch/usermode/usermode/syscall.c
cvs rdiff -u -r1.56 -r1.57 src/sys/arch/usermode/usermode/trap.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/usermode/dev/cpu.c
diff -u src/sys/arch/usermode/dev/cpu.c:1.64 src/sys/arch/usermode/dev/cpu.c:1.65
--- src/sys/arch/usermode/dev/cpu.c:1.64 Sat Jan 14 17:42:51 2012
+++ src/sys/arch/usermode/dev/cpu.c Sat Jan 14 21:45:28 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: cpu.c,v 1.64 2012/01/14 17:42:51 reinoud Exp $ */
+/* $NetBSD: cpu.c,v 1.65 2012/01/14 21:45:28 reinoud Exp $ */
/*-
* Copyright (c) 2007 Jared D. McNeill <jmcne...@invisible.ca>
@@ -30,7 +30,7 @@
#include "opt_hz.h"
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.64 2012/01/14 17:42:51 reinoud Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.65 2012/01/14 21:45:28 reinoud Exp $");
#include <sys/param.h>
#include <sys/conf.h>
@@ -43,6 +43,7 @@ __KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.64
#include <sys/mbuf.h>
#include <sys/msgbuf.h>
#include <sys/kmem.h>
+#include <sys/kernel.h>
#include <dev/cons.h>
@@ -155,6 +156,7 @@ void
cpu_need_resched(struct cpu_info *ci, int flags)
{
ci->ci_want_resched |= flags;
+ aston(ci);
}
void
Index: src/sys/arch/usermode/usermode/syscall.c
diff -u src/sys/arch/usermode/usermode/syscall.c:1.21 src/sys/arch/usermode/usermode/syscall.c:1.22
--- src/sys/arch/usermode/usermode/syscall.c:1.21 Sat Jan 14 17:42:52 2012
+++ src/sys/arch/usermode/usermode/syscall.c Sat Jan 14 21:45:28 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: syscall.c,v 1.21 2012/01/14 17:42:52 reinoud Exp $ */
+/* $NetBSD: syscall.c,v 1.22 2012/01/14 21:45:28 reinoud Exp $ */
/*-
* Copyright (c) 2007 Jared D. McNeill <jmcne...@invisible.ca>
@@ -27,7 +27,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.21 2012/01/14 17:42:52 reinoud Exp $");
+__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.22 2012/01/14 21:45:28 reinoud Exp $");
#include <sys/types.h>
#include <sys/param.h>
@@ -45,16 +45,6 @@ __KERNEL_RCSID(0, "$NetBSD: syscall.c,v
#include <machine/thunk.h>
#include <machine/machdep.h>
-
-void userret(struct lwp *l);
-
-void
-userret(struct lwp *l)
-{
- /* invoke MI userret code */
- mi_userret(l);
-}
-
void
child_return(void *arg)
{
@@ -161,7 +151,6 @@ syscall(void)
}
//thunk_printf_debug("end of syscall : return to userland\n");
//if (code != 4) thunk_printf("userret() code %d\n", code);
- userret(l);
}
Index: src/sys/arch/usermode/usermode/trap.c
diff -u src/sys/arch/usermode/usermode/trap.c:1.56 src/sys/arch/usermode/usermode/trap.c:1.57
--- src/sys/arch/usermode/usermode/trap.c:1.56 Sat Jan 14 17:42:52 2012
+++ src/sys/arch/usermode/usermode/trap.c Sat Jan 14 21:45:28 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: trap.c,v 1.56 2012/01/14 17:42:52 reinoud Exp $ */
+/* $NetBSD: trap.c,v 1.57 2012/01/14 21:45:28 reinoud Exp $ */
/*-
* Copyright (c) 2011 Reinoud Zandijk <rein...@netbsd.org>
@@ -27,7 +27,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.56 2012/01/14 17:42:52 reinoud Exp $");
+__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.57 2012/01/14 21:45:28 reinoud Exp $");
#include <sys/types.h>
#include <sys/param.h>
@@ -50,6 +50,7 @@ __KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.5
/* forwards and externals */
void setup_signal_handlers(void);
void stop_all_signal_handlers(void);
+void userret(struct lwp *l);
static void mem_access_handler(int sig, siginfo_t *info, void *ctx);
static void illegal_instruction_handler(int sig, siginfo_t *info, void *ctx);
@@ -62,6 +63,7 @@ bool pmap_fault(pmap_t pmap, vaddr_t va,
static stack_t sigstk;
+int astpending;
void
startlwp(void *arg)
@@ -203,6 +205,49 @@ mem_access_handler(int sig, siginfo_t *i
}
+/* ast and userret */
+void
+userret(struct lwp *l)
+{
+ struct pcb *pcb;
+ ucontext_t ucp, *nucp;
+ vaddr_t pc;
+
+ KASSERT(l);
+
+ /* are we going back to userland? */
+ pcb = lwp_getpcb(l);
+ KASSERT(pcb);
+
+ /* where are we going back to ? */
+ thunk_getcontext(&ucp);
+ nucp = (ucontext_t *) ucp.uc_link;
+ pc = md_get_pc(nucp);
+
+ if (pc >= kmem_k_start)
+ return;
+
+ /* ok, going to userland, proceed! */
+ if (astpending) {
+ astpending = 0;
+
+ curcpu()->ci_data.cpu_ntrap++;
+#if 0
+ /* profiling */
+ if (l->l_pflag & LP_OWEUPC) {
+ l->l_pflag &= ~LP_OWEUPC;
+ ADDUPROF(l);
+ }
+#endif
+ /* allow a forced task switch */
+ if (l->l_cpu->ci_want_resched)
+ preempt();
+ }
+
+ /* invoke MI userret code */
+ mi_userret(l);
+}
+
/* signal handler switching to a illegal instruction context */
static void
illegal_instruction_handler(int sig, siginfo_t *info, void *ctx)
@@ -317,10 +362,11 @@ pagefault(vaddr_t pc, vaddr_t va)
(void *) pc, (void *) va);
#endif
- /* can pmap handle it? on its own? (r/m) */
+ /* can pmap handle it? on its own? (r/m) emulation */
if (pmap_fault(vm_map->pmap, va, &atype)) {
// thunk_printf("pagefault leave (pmap)\n");
- goto out;
+ /* no use doing anything else here */
+ goto out_quick;
}
/* ask UVM */
@@ -386,10 +432,11 @@ pagefault(vaddr_t pc, vaddr_t va)
#else
trapsignal(l, &ksi);
#endif
- mi_userret(l);
// thunk_printf("pagefault leave\n");
out:
+ userret(l);
+out_quick:
thunk_seterrno(lwp_errno);
pcb->pcb_errno = lwp_errno;
}
@@ -410,6 +457,7 @@ illegal_instruction(void)
if (md_syscall_check_opcode(ucp)) {
syscall();
// thunk_printf("illegal instruction leave\n");
+ userret(l);
return;
}
@@ -427,6 +475,6 @@ illegal_instruction(void)
#else
trapsignal(l, &ksi);
#endif
- mi_userret(l);
+ userret(l);
}
