Module Name: src
Committed By: riastradh
Date: Sun Aug 2 18:23:33 UTC 2020
Modified Files:
src/sys/arch/x86/x86: fpu.c
Log Message:
Revert "Add kthread_fpu_enter/exit support to x86." for now.
Need to find all the paths out of interrupts back into _kernel_
context to add HANDLE_DEFERRED_FPU, I think, before this can be
enabled.
To generate a diff of this commit:
cvs rdiff -u -r1.73 -r1.74 src/sys/arch/x86/x86/fpu.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/x86/x86/fpu.c
diff -u src/sys/arch/x86/x86/fpu.c:1.73 src/sys/arch/x86/x86/fpu.c:1.74
--- src/sys/arch/x86/x86/fpu.c:1.73 Sat Aug 1 02:13:34 2020
+++ src/sys/arch/x86/x86/fpu.c Sun Aug 2 18:23:33 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: fpu.c,v 1.73 2020/08/01 02:13:34 riastradh Exp $ */
+/* $NetBSD: fpu.c,v 1.74 2020/08/02 18:23:33 riastradh Exp $ */
/*
* Copyright (c) 2008, 2019 The NetBSD Foundation, Inc. All
@@ -96,7 +96,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: fpu.c,v 1.73 2020/08/01 02:13:34 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: fpu.c,v 1.74 2020/08/02 18:23:33 riastradh Exp $");
#include "opt_multiprocessor.h"
@@ -107,7 +107,6 @@ __KERNEL_RCSID(0, "$NetBSD: fpu.c,v 1.73
#include <sys/file.h>
#include <sys/proc.h>
#include <sys/kernel.h>
-#include <sys/kthread.h>
#include <sys/sysctl.h>
#include <sys/xcall.h>
@@ -132,35 +131,13 @@ void fpu_switch(struct lwp *, struct lwp
uint32_t x86_fpu_mxcsr_mask __read_mostly = 0;
-/*
- * True if this a thread that is allowed to use the FPU -- either a
- * user thread, or a system thread with LW_SYSTEM_FPU enabled.
- */
-static inline bool
-lwp_can_haz_fpu(struct lwp *l)
-{
-
- return (l->l_flag & (LW_SYSTEM|LW_SYSTEM_FPU)) != LW_SYSTEM;
-}
-
-/*
- * True if this is a system thread with its own private FPU state.
- */
-static inline bool
-lwp_system_fpu_p(struct lwp *l)
-{
-
- return (l->l_flag & (LW_SYSTEM|LW_SYSTEM_FPU)) ==
- (LW_SYSTEM|LW_SYSTEM_FPU);
-}
-
static inline union savefpu *
fpu_lwp_area(struct lwp *l)
{
struct pcb *pcb = lwp_getpcb(l);
union savefpu *area = &pcb->pcb_savefpu;
- KASSERT(lwp_can_haz_fpu(l));
+ KASSERT((l->l_flag & LW_SYSTEM) == 0);
if (l == curlwp) {
fpu_save();
}
@@ -178,7 +155,7 @@ fpu_save_lwp(struct lwp *l)
s = splvm();
if (l->l_md.md_flags & MDL_FPU_IN_CPU) {
- KASSERT(lwp_can_haz_fpu(l));
+ KASSERT((l->l_flag & LW_SYSTEM) == 0);
fpu_area_save(area, x86_xsave_features);
l->l_md.md_flags &= ~MDL_FPU_IN_CPU;
}
@@ -330,7 +307,7 @@ fpu_switch(struct lwp *oldlwp, struct lw
cpu_index(ci), ci->ci_ilevel);
if (oldlwp->l_md.md_flags & MDL_FPU_IN_CPU) {
- KASSERT(lwp_can_haz_fpu(oldlwp));
+ KASSERT(!(oldlwp->l_flag & LW_SYSTEM));
pcb = lwp_getpcb(oldlwp);
fpu_area_save(&pcb->pcb_savefpu, x86_xsave_features);
oldlwp->l_md.md_flags &= ~MDL_FPU_IN_CPU;
@@ -345,11 +322,11 @@ fpu_lwp_fork(struct lwp *l1, struct lwp
union savefpu *fpu_save;
/* Kernel threads have no FPU. */
- if (__predict_false(!lwp_can_haz_fpu(l2))) {
+ if (__predict_false(l2->l_flag & LW_SYSTEM)) {
return;
}
/* For init(8). */
- if (__predict_false(!lwp_can_haz_fpu(l1))) {
+ if (__predict_false(l1->l_flag & LW_SYSTEM)) {
memset(&pcb2->pcb_savefpu, 0, x86_fpu_save_size);
return;
}
@@ -373,8 +350,6 @@ fpu_lwp_abandon(struct lwp *l)
/* -------------------------------------------------------------------------- */
-static const union savefpu zero_fpu __aligned(64);
-
/*
* fpu_kern_enter()
*
@@ -394,11 +369,6 @@ fpu_kern_enter(void)
struct cpu_info *ci;
int s;
- if (lwp_system_fpu_p(l) && !cpu_intr_p()) {
- KASSERT(!cpu_softintr_p());
- return;
- }
-
s = splvm();
ci = curcpu();
@@ -431,16 +401,10 @@ fpu_kern_enter(void)
void
fpu_kern_leave(void)
{
- struct cpu_info *ci;
+ static const union savefpu zero_fpu __aligned(64);
+ struct cpu_info *ci = curcpu();
int s;
- if (lwp_system_fpu_p(curlwp) && !cpu_intr_p()) {
- KASSERT(!cpu_softintr_p());
- return;
- }
-
- ci = curcpu();
-
KASSERT(ci->ci_ilevel == IPL_VM);
KASSERT(ci->ci_kfpu_spl != -1);
@@ -462,23 +426,6 @@ fpu_kern_leave(void)
splx(s);
}
-void
-kthread_fpu_enter_md(void)
-{
-
- /* Enable the FPU by clearing CR0_TS. */
- clts();
-}
-
-void
-kthread_fpu_exit_md(void)
-{
-
- /* Zero the FPU state and disable the FPU by setting CR0_TS. */
- fpu_area_restore(&zero_fpu, x86_xsave_features);
- stts();
-}
-
/* -------------------------------------------------------------------------- */
/*
