Module Name: src
Committed By: reinoud
Date: Tue May 29 07:09:22 UTC 2018
Modified Files:
src/sys/arch/usermode/dev: cpu.c
Log Message:
Only set requested parts of the mcontext in cpu_setmcontext()
Make the atomic switcher `atomic' by using splhigh()
To generate a diff of this commit:
cvs rdiff -u -r1.76 -r1.77 src/sys/arch/usermode/dev/cpu.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:1.76 src/sys/arch/usermode/dev/cpu.c:1.77
--- src/sys/arch/usermode/dev/cpu.c:1.76 Thu May 24 19:39:04 2018
+++ src/sys/arch/usermode/dev/cpu.c Tue May 29 07:09:21 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: cpu.c,v 1.76 2018/05/24 19:39:04 reinoud Exp $ */
+/* $NetBSD: cpu.c,v 1.77 2018/05/29 07:09:21 reinoud Exp $ */
/*-
* Copyright (c) 2007 Jared D. McNeill <[email protected]>
@@ -30,7 +30,7 @@
#include "opt_hz.h"
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.76 2018/05/24 19:39:04 reinoud Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.77 2018/05/29 07:09:21 reinoud Exp $");
#include <sys/param.h>
#include <sys/conf.h>
@@ -194,7 +194,6 @@ cpu_need_proftick(struct lwp *l)
}
-/* XXX make sure this is atomic? */
static
void
cpu_switchto_atomic(lwp_t *oldlwp, lwp_t *newlwp)
@@ -202,19 +201,22 @@ cpu_switchto_atomic(lwp_t *oldlwp, lwp_t
struct pcb *oldpcb;
struct pcb *newpcb;
struct cpu_info *ci;
+ int s;
oldpcb = oldlwp ? lwp_getpcb(oldlwp) : NULL;
newpcb = lwp_getpcb(newlwp);
ci = curcpu();
- ci->ci_stash = oldlwp;
+ s = splhigh();
+ ci->ci_stash = oldlwp;
if (oldpcb)
oldpcb->pcb_errno = thunk_geterrno();
thunk_seterrno(newpcb->pcb_errno);
/* set both ucontexts up for TLS just in case */
+
newpcb->pcb_ucp.uc_mcontext._mc_tlsbase =
(uintptr_t) newlwp->l_private;
newpcb->pcb_ucp.uc_flags |= _UC_TLSBASE;
@@ -224,8 +226,11 @@ cpu_switchto_atomic(lwp_t *oldlwp, lwp_t
newpcb->pcb_userret_ucp.uc_flags |= _UC_TLSBASE;
curlwp = newlwp;
+ splx(s);
+
if (thunk_setcontext(&newpcb->pcb_ucp))
panic("setcontext failed");
+
/* not reached */
}
@@ -341,11 +346,28 @@ cpu_setmcontext(struct lwp *l, const mco
#ifdef CPU_DEBUG
thunk_printf_debug("cpu_setmcontext\n");
#endif
- ucp->uc_flags = flags;
- memcpy(&ucp->uc_mcontext, mcp, sizeof(mcontext_t));
+ if ((flags & _UC_CPU) != 0)
+ memcpy(&ucp->uc_mcontext.__gregs, mcp->__gregs, sizeof(__gregset_t));
+ if ((flags & _UC_FPU) != 0)
+ memcpy(&ucp->uc_mcontext.__fpregs, mcp->__fpregs, sizeof(__fpregset_t));
+ if ((flags & _UC_TLSBASE) != 0)
+ lwp_setprivate(l, (void *) (uintptr_t) mcp->_mc_tlsbase);
- /* update our private, it might be altered in userland */
- l->l_private = (void *) ucp->uc_mcontext._mc_tlsbase;
+#if 0
+ /*
+ * XXX we ignore the set and clear stack since signals are done
+ * slightly differently.
+ */
+thunk_printf("%s: flags %x\n", __func__, flags);
+ mutex_enter(l->l_proc->p_lock);
+ if (flags & _UC_SETSTACK)
+ l->l_sigstk.ss_flags |= SS_ONSTACK;
+ if (flags & _UC_CLRSTACK)
+ l->l_sigstk.ss_flags &= ~SS_ONSTACK;
+ mutex_exit(l->l_proc->p_lock);
+#endif
+
+ ucp->uc_flags |= (flags & (_UC_CPU | _UC_FPU | _UC_TLSBASE));
return 0;
}
@@ -410,7 +432,6 @@ cpu_lwp_fork(struct lwp *l1, struct lwp
l2 ? l2->l_name : "none", l2,
stack, (int)stacksize);
#endif
-
if (stack)
panic("%s: stack passed, can't handle\n", __func__);
