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freebsd-skq/sys/kern/subr_trap.c

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Initial import, 0.1 + pk 0.2.4-B1
1993-06-12 14:58:17 +00:00
/*-
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
* Copyright (C) 1994, David Greenman
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
Initial import, 0.1 + pk 0.2.4-B1
1993-06-12 14:58:17 +00:00
*
* This code is derived from software contributed to Berkeley by
* the University of Utah, and William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
genassym.c: Remove NKMEMCLUSTERS, it is no longer define or used. locores.s: Fix comment on PTDpde and APTDpde to be pde instead of pte Add new equation for calculating location of Sysmap Remove Bill's old #ifdef garbage for counting up memory, that stuff will never be made to work and was just cluttering up the file. Add code that places the PTD, page table pages, and kernel stack below the 640k ISA hole if there is room for it, otherwise put this stuff all at 1MB. This fixes the 28K bogusity in the boot blocks, that can now go away! Fix the caclulation of where first is to be dependent on NKPDE so that we can skip over the above mentioned areas. The 28K thing is now 44K in size due to the increase in kernel virtual memory space, but since we no longer have to worry about that this is no big deal. Use if NNPX > 0 instead of ifdef NPX for floating point code. machdep.c Change the calculation of for the buffer cache to be 20% of all memory above 2MB and add back the upper limit of 2/5's of the VM_KMEM_SIZE so that we do not eat ALL of the kernel memory space on large memory machines, note that this will not even come into effect unless you have more than 32MB. The current buffer cache limit is 6.7MB due to this caclulation. It seems that we where erroniously allocating bufpages pages for buffer_map. buffer_map is UNUSED in this implementation of the buffer cache, but since the map is referenced in several if statements a quick fix was to simply allocate 1 vm page (but no real memory) to it. pmap.h Remove rcsid, don't want them in the kernel files! Removed some cruft inside an #ifdef DEBUGx that caused compiler errors if you where compiling this for debug. Use the #defines for PD_SHIFT and PG_SHIFT in place of constants. trap.c: Remove patch kit header and rcsid, fix $Id$. Now include "npx.h" and use NNPX for controlling the floating point code. Remove a now completly invalid check for a maximum virtual address, the virtual address now ends at 0xFFFFFFFF so there is no more MAX!! (Thanks David, I completly missed that one!) vm_machdep.c Remove patch kit header and rcsid, fix $Id$. Now include "npx.h" and use NNPX for controlling the floating point code. Replace several 0xFE00000 constants with KERNBASE
1993-10-15 10:34:29 +00:00
* from: @(#)trap.c 7.4 (Berkeley) 5/13/91
$Id$ -> $FreeBSD$
1999-08-28 01:08:13 +00:00
* $FreeBSD$
Initial import, 0.1 + pk 0.2.4-B1
1993-06-12 14:58:17 +00:00
*/
Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.
2001-06-29 19:51:37 +00:00
#ifdef __i386__
Use #ifdef DEV_NPX from opt_npx.h instead of #if NNPX > 0 from npx.h
2001-01-19 13:19:02 +00:00
#include "opt_npx.h"
Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.
2001-06-29 19:51:37 +00:00
#endif
Converted two options over to the new scheme: USER_LDT and KTRACE.
1996-01-03 21:42:35 +00:00
The big 4.4BSD Lite to FreeBSD 2.0.0 (Development) patch. Reviewed by: Rodney W. Grimes Submitted by: John Dyson and David Greenman
1994-05-25 09:21:21 +00:00
#include <sys/param.h>
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
#include <sys/bus.h>
The big 4.4BSD Lite to FreeBSD 2.0.0 (Development) patch. Reviewed by: Rodney W. Grimes Submitted by: John Dyson and David Greenman
1994-05-25 09:21:21 +00:00
#include <sys/kernel.h>
Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.
2001-06-29 19:51:37 +00:00
#include <sys/lock.h>
Catch up to moving headers: - machine/ipl.h -> sys/ipl.h - machine/mutex.h -> sys/mutex.h
2000-10-20 07:58:15 +00:00
#include <sys/mutex.h>
Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.
2001-06-29 19:51:37 +00:00
#include <sys/proc.h>
Fixed some #include messes. Hid the check of the user %cs in syscall() under `#ifdef DIAGNOSTIC'.
1997-11-24 13:25:37 +00:00
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.
2001-06-29 19:51:37 +00:00
#include <sys/systm.h>
Untangled the vm.h include file spaghetti.
1995-12-07 12:48:31 +00:00
#include <sys/vmmeter.h>
The big 4.4BSD Lite to FreeBSD 2.0.0 (Development) patch. Reviewed by: Rodney W. Grimes Submitted by: John Dyson and David Greenman
1994-05-25 09:21:21 +00:00
#include <machine/cpu.h>
Fixed some #include messes. Hid the check of the user %cs in syscall() under `#ifdef DIAGNOSTIC'.
1997-11-24 13:25:37 +00:00
#include <machine/pcb.h>
- Add code to detect if a system call returns with locks other than Giant held and panic if so (conditional on witness). - Change witness_list to return the number of locks held so this is easier. - Add kern/syscalls.c to the kernel build if witness is defined so that the panic message can contain the name of the offending system call. - Add assertions that Giant and sched_lock are not held when returning from a system call, which were missing for alpha and ia64.
2000-12-12 01:14:32 +00:00
Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.
2001-06-29 19:51:37 +00:00
/*
* Define the code needed before returning to user mode, for
* trap and syscall.
*/
- Kill the have_giant parameter to userret() along with all instances of that name as a variable. Use mtx_owned(&Giant) where appropriate instead. - Proc locking. - P_FOO -> PS_FOO. - Update comments about enable interrupts during trap and why this may be bad if we trap while holding a spin mutex. - Don't bother resetting p to curproc in syscall() in case we are the child returning from fork. The child hasn't returned from fork through syscall in a while. - Remove fork_return() as it has been superseded by the MI version.
2001-01-24 09:53:49 +00:00
void
userret(p, frame, oticks)
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
struct proc *p;
struct trapframe *frame;
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
u_int oticks;
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
{
- Kill the have_giant parameter to userret() along with all instances of that name as a variable. Use mtx_owned(&Giant) where appropriate instead. - Proc locking. - P_FOO -> PS_FOO. - Update comments about enable interrupts during trap and why this may be bad if we trap while holding a spin mutex. - Don't bother resetting p to curproc in syscall() in case we are the child returning from fork. The child hasn't returned from fork through syscall in a while. - Remove fork_return() as it has been superseded by the MI version.
2001-01-24 09:53:49 +00:00
int sig;
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
Grab Giant around postsig() since sendsig() can call into the vm to grow the stack and we already needed Giant for KTRACE.
2001-07-03 05:27:53 +00:00
mtx_lock(&Giant);
- Grab the proc lock around CURSIG and postsig(). Don't release the proc lock until after grabbing the sched_lock to avoid CURSIG racing with psignal. - Don't grab Giant for addupc_task() as it isn't needed. Reported by: tegge (signal race), bde (addupc_task a while back)
2001-06-22 23:05:11 +00:00
PROC_LOCK(p);
- Release Giant a bit earlier on syscall exit. - Don't try to grab Giant before postsig() in userret() as it is no longer needed. - Don't grab Giant before psignal() in ast() but get the proc lock instead.
2001-03-07 03:53:39 +00:00
while ((sig = CURSIG(p)) != 0)
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
postsig(sig);
Grab Giant around postsig() since sendsig() can call into the vm to grow the stack and we already needed Giant for KTRACE.
2001-07-03 05:27:53 +00:00
mtx_unlock(&Giant);
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
PROC_UNLOCK(p);
Commit major SMP cleanups and move the BGL (big giant lock) in the syscall path inward. A system call may select whether it needs the MP lock or not (the default being that it does need it). A great deal of conditional SMP code for various deadended experiments has been removed. 'cil' and 'cml' have been removed entirely, and the locking around the cpl has been removed. The conditional separately-locked fast-interrupt code has been removed, meaning that interrupts must hold the CPL now (but they pretty much had to anyway). Another reason for doing this is that the original separate-lock for interrupts just doesn't apply to the interrupt thread mechanism being contemplated. Modifications to the cpl may now ONLY occur while holding the MP lock. For example, if an otherwise MP safe syscall needs to mess with the cpl, it must hold the MP lock for the duration and must (as usual) save/restore the cpl in a nested fashion. This is precursor work for the real meat coming later: avoiding having to hold the MP lock for common syscalls and I/O's and interrupt threads. It is expected that the spl mechanisms and new interrupt threading mechanisms will be able to run in tandem, allowing a slow piecemeal transition to occur. This patch should result in a moderate performance improvement due to the considerable amount of code that has been removed from the critical path, especially the simplification of the spl*() calls. The real performance gains will come later. Approved by: jkh Reviewed by: current, bde (exception.s) Some work taken from: luoqi's patch
2000-03-28 07:16:37 +00:00
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&sched_lock);
Implement a unified run queue and adjust priority levels accordingly. - All processes go into the same array of queues, with different scheduling classes using different portions of the array. This allows user processes to have their priorities propogated up into interrupt thread range if need be. - I chose 64 run queues as an arbitrary number that is greater than 32. We used to have 4 separate arrays of 32 queues each, so this may not be optimal. The new run queue code was written with this in mind; changing the number of run queues only requires changing constants in runq.h and adjusting the priority levels. - The new run queue code takes the run queue as a parameter. This is intended to be used to create per-cpu run queues. Implement wrappers for compatibility with the old interface which pass in the global run queue structure. - Group the priority level, user priority, native priority (before propogation) and the scheduling class into a struct priority. - Change any hard coded priority levels that I found to use symbolic constants (TTIPRI and TTOPRI). - Remove the curpriority global variable and use that of curproc. This was used to detect when a process' priority had lowered and it should yield. We now effectively yield on every interrupt. - Activate propogate_priority(). It should now have the desired effect without needing to also propogate the scheduling class. - Temporarily comment out the call to vm_page_zero_idle() in the idle loop. It interfered with propogate_priority() because the idle process needed to do a non-blocking acquire of Giant and then other processes would try to propogate their priority onto it. The idle process should not do anything except idle. vm_page_zero_idle() will return in the form of an idle priority kernel thread which is woken up at apprioriate times by the vm system. - Update struct kinfo_proc to the new priority interface. Deliberately change its size by adjusting the spare fields. It remained the same size, but the layout has changed, so userland processes that use it would parse the data incorrectly. The size constraint should really be changed to an arbitrary version number. Also add a debug.sizeof sysctl node for struct kinfo_proc.
2001-02-12 00:20:08 +00:00
p->p_pri.pri_level = p->p_pri.pri_user;
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
if (p->p_sflag & PS_NEEDRESCHED) {
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
/*
Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.
2001-06-29 19:51:37 +00:00
* Since we are curproc, a clock interrupt could
* change our priority without changing run queues
* (the running process is not kept on a run queue).
* If this happened after we setrunqueue ourselves but
* before we switch()'ed, we might not be on the queue
* indicated by our priority.
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
*/
- Split the run queue and sleep queue linkage, so that a process may block on a mutex while on the sleep queue without corrupting it. - Move dropping of Giant to after the acquire of sched_lock. Tested by: John Hay <jhay@icomtek.csir.co.za> jhb
2000-11-17 18:09:18 +00:00
DROP_GIANT_NOSWITCH();
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
setrunqueue(p);
p->p_stats->p_ru.ru_nivcsw++;
mi_switch();
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&sched_lock);
Don't release and acquire Giant in mi_switch(). Instead, release and acquire Giant as needed in functions that call mi_switch(). The releases need to be done outside of the sched_lock to avoid potential deadlocks from trying to acquire Giant while interrupts are disabled. Submitted by: witness
2000-11-16 02:16:44 +00:00
PICKUP_GIANT();
postsig() currently requires Giant to be held. Giant is held properly at the first postsig() call, but not always held at the second place, resulting in an occassional panic.
2001-07-04 15:36:30 +00:00
mtx_lock(&Giant);
- Grab the proc lock around CURSIG and postsig(). Don't release the proc lock until after grabbing the sched_lock to avoid CURSIG racing with psignal. - Don't grab Giant for addupc_task() as it isn't needed. Reported by: tegge (signal race), bde (addupc_task a while back)
2001-06-22 23:05:11 +00:00
PROC_LOCK(p);
- Release Giant a bit earlier on syscall exit. - Don't try to grab Giant before postsig() in userret() as it is no longer needed. - Don't grab Giant before psignal() in ast() but get the proc lock instead.
2001-03-07 03:53:39 +00:00
while ((sig = CURSIG(p)) != 0)
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
postsig(sig);
postsig() currently requires Giant to be held. Giant is held properly at the first postsig() call, but not always held at the second place, resulting in an occassional panic.
2001-07-04 15:36:30 +00:00
mtx_unlock(&Giant);
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
PROC_UNLOCK(p);
} else
mtx_unlock_spin(&sched_lock);
- Kill the have_giant parameter to userret() along with all instances of that name as a variable. Use mtx_owned(&Giant) where appropriate instead. - Proc locking. - P_FOO -> PS_FOO. - Update comments about enable interrupts during trap and why this may be bad if we trap while holding a spin mutex. - Don't bother resetting p to curproc in syscall() in case we are the child returning from fork. The child hasn't returned from fork through syscall in a while. - Remove fork_return() as it has been superseded by the MI version.
2001-01-24 09:53:49 +00:00
Check P_PROFIL flag for profiling rather than pr_scale as it makes more sense.
1995-02-10 06:25:14 +00:00
/*
* Charge system time if profiling.
*/
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
if (p->p_sflag & PS_PROFIL)
- Make astpending and need_resched process attributes rather than CPU attributes. This is needed for AST's to be properly posted in a preemptive kernel. They are backed by two new flags in p_sflag: PS_ASTPENDING and PS_NEEDRESCHED. They are still accesssed by their old macros: aston(), astoff(), etc. For completeness, an astpending() macro has been added to check for a pending AST, and clear_resched() has been added to clear need_resched(). - Rename syscall2() on the x86 back to syscall() to be consistent with other architectures.
2001-02-10 02:20:34 +00:00
addupc_task(p, TRAPF_PC(frame),
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
((u_int)p->p_sticks - oticks) * psratio);
trap.c: Vastly improved trap.c from me. This rewritten version has a variety of features, amoung them: higher performance and much higher code quality. support.s, cpufunc.h: No longer use gs override to enforce range limits - compare directly against VM_MAXUSER_ADDRESS instead. The old way caused problems in preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
}
Initial import, 0.1 + pk 0.2.4-B1
1993-06-12 14:58:17 +00:00
/*
Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.
2001-06-29 19:51:37 +00:00
* Process an asynchronous software trap.
* This is relatively easy.
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
* This function will return with preemption disabled.
Initial import, 0.1 + pk 0.2.4-B1
1993-06-12 14:58:17 +00:00
*/
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
void
- Change ast() to take a pointer to a trapframe like other architectures. - Don't use an atomic operation to update cnt.v_soft in ast(). This is the only place the variable is written to, and sched_lock is always held when it is written, so it is already protected and the mutex release of sched_lock asserts a memory barrier that ensures the value will be updated in a timely fashion.
2001-02-22 18:05:15 +00:00
ast(framep)
struct trapframe *framep;
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
{
struct proc *p = CURPROC;
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
u_int prticks, sticks;
critical_t s;
int sflag;
Convert npx interrupts into traps instead of vice versa. This is much simpler for npx exceptions that start as traps (no assembly required...) and works better for npx exceptions that start as interrupts (there is no longer a problem for nested interrupts). Submitted by: original (pre-SMPng) version by luoqi
2001-05-22 21:20:49 +00:00
#if defined(DEV_NPX) && !defined(SMP)
int ucode;
#endif
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
- Change ast() to take a pointer to a trapframe like other architectures. - Don't use an atomic operation to update cnt.v_soft in ast(). This is the only place the variable is written to, and sched_lock is always held when it is written, so it is already protected and the mutex release of sched_lock asserts a memory barrier that ensures the value will be updated in a timely fashion.
2001-02-22 18:05:15 +00:00
KASSERT(TRAPF_USERMODE(framep), ("ast in kernel mode"));
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
#ifdef WITNESS
if (witness_list(p))
panic("Returning to user mode with mutex(s) held");
#endif
mtx_assert(&Giant, MA_NOTOWNED);
s = critical_enter();
while ((p->p_sflag & (PS_ASTPENDING | PS_NEEDRESCHED)) != 0) {
critical_exit(s);
p->p_frame = framep;
/*
* This updates the p_sflag's for the checks below in one
* "atomic" operation with turning off the astpending flag.
* If another AST is triggered while we are handling the
* AST's saved in sflag, the astpending flag will be set and
* we will loop again.
*/
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&sched_lock);
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
sticks = p->p_sticks;
sflag = p->p_sflag;
p->p_sflag &= ~(PS_OWEUPC | PS_ALRMPEND | PS_PROFPEND |
PS_ASTPENDING);
cnt.v_soft++;
if (sflag & PS_OWEUPC) {
prticks = p->p_stats->p_prof.pr_ticks;
p->p_stats->p_prof.pr_ticks = 0;
mtx_unlock_spin(&sched_lock);
addupc_task(p, p->p_stats->p_prof.pr_addr, prticks);
} else
mtx_unlock_spin(&sched_lock);
if (sflag & PS_ALRMPEND) {
PROC_LOCK(p);
psignal(p, SIGVTALRM);
PROC_UNLOCK(p);
}
Convert npx interrupts into traps instead of vice versa. This is much simpler for npx exceptions that start as traps (no assembly required...) and works better for npx exceptions that start as interrupts (there is no longer a problem for nested interrupts). Submitted by: original (pre-SMPng) version by luoqi
2001-05-22 21:20:49 +00:00
#if defined(DEV_NPX) && !defined(SMP)
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
if (PCPU_GET(curpcb)->pcb_flags & PCB_NPXTRAP) {
atomic_clear_char(&PCPU_GET(curpcb)->pcb_flags,
PCB_NPXTRAP);
ucode = npxtrap();
if (ucode != -1) {
Convert npx interrupts into traps instead of vice versa. This is much simpler for npx exceptions that start as traps (no assembly required...) and works better for npx exceptions that start as interrupts (there is no longer a problem for nested interrupts). Submitted by: original (pre-SMPng) version by luoqi
2001-05-22 21:20:49 +00:00
mtx_lock(&Giant);
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
trapsignal(p, SIGFPE, ucode);
}
Convert npx interrupts into traps instead of vice versa. This is much simpler for npx exceptions that start as traps (no assembly required...) and works better for npx exceptions that start as interrupts (there is no longer a problem for nested interrupts). Submitted by: original (pre-SMPng) version by luoqi
2001-05-22 21:20:49 +00:00
}
#endif
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
if (sflag & PS_PROFPEND) {
PROC_LOCK(p);
psignal(p, SIGPROF);
PROC_UNLOCK(p);
}
The biggie: Get rid of the UPAGES from the top of the per-process address space. (!) Have each process use the kernel stack and pcb in the kvm space. Since the stacks are at a different address, we cannot copy the stack at fork() and allow the child to return up through the function call tree to return to user mode - create a new execution context and have the new process begin executing from cpu_switch() and go to user mode directly. In theory this should speed up fork a bit. Context switch the tss_esp0 pointer in the common tss. This is a lot simpler since than swithching the gdt[GPROC0_SEL].sd.sd_base pointer to each process's tss since the esp0 pointer is a 32 bit pointer, and the sd_base setting is split into three different bit sections at non-aligned boundaries and requires a lot of twiddling to reset. The 8K of memory at the top of the process space is now empty, and unmapped (and unmappable, it's higher than VM_MAXUSER_ADDRESS). Simplity the pmap code to manage process contexts, we no longer have to double map the UPAGES, this simplifies and should measuably speed up fork(). The following parts came from John Dyson: Set PG_G on the UPAGES that are now in kernel context, and invalidate them when swapping them out. Move the upages object (upobj) from the vmspace to the proc structure. Now that the UPAGES (pcb and kernel stack) are out of user space, make rfork(..RFMEM..) do what was intended by sharing the vmspace entirely via reference counting rather than simply inheriting the mappings.
1997-04-07 07:16:06 +00:00
- Close races with signals and other AST's being triggered while we are in the process of exiting the kernel. The ast() function now loops as long as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with preemption disabled so that any further AST's that arrive via an interrupt will be delayed until the low-level MD code returns to user mode. - Use u_int's to store the tick counts for profiling purposes so that we do not need sched_lock just to read p_sticks. This also closes a problem where the call to addupc_task() could screw up the arithmetic due to non-atomic reads of p_sticks. - Axe need_proftick(), aston(), astoff(), astpending(), need_resched(), clear_resched(), and resched_wanted() in favor of direct bit operations on p_sflag. - Fix up locking with sched_lock some. In addupc_intr(), use sched_lock to ensure pr_addr and pr_ticks are updated atomically with setting PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing PS_OWEUPC. We also do not grab the lock just to test a flag. - Simplify the handling of Giant in ast() slightly. Reviewed by: bde (mostly)
2001-08-10 22:53:32 +00:00
userret(p, framep, sticks);
if (mtx_owned(&Giant))
mtx_unlock(&Giant);
s = critical_enter();
}
mtx_assert(&Giant, MA_NOTOWNED);
/*
* We need to keep interrupts disabled so that if any further AST's
* come in, the interrupt they come in on will be delayed until we
* finish returning to userland. We assume that the return to userland
* will perform the equivalent of critical_exit().
*/
The biggie: Get rid of the UPAGES from the top of the per-process address space. (!) Have each process use the kernel stack and pcb in the kvm space. Since the stacks are at a different address, we cannot copy the stack at fork() and allow the child to return up through the function call tree to return to user mode - create a new execution context and have the new process begin executing from cpu_switch() and go to user mode directly. In theory this should speed up fork a bit. Context switch the tss_esp0 pointer in the common tss. This is a lot simpler since than swithching the gdt[GPROC0_SEL].sd.sd_base pointer to each process's tss since the esp0 pointer is a 32 bit pointer, and the sd_base setting is split into three different bit sections at non-aligned boundaries and requires a lot of twiddling to reset. The 8K of memory at the top of the process space is now empty, and unmapped (and unmappable, it's higher than VM_MAXUSER_ADDRESS). Simplity the pmap code to manage process contexts, we no longer have to double map the UPAGES, this simplifies and should measuably speed up fork(). The following parts came from John Dyson: Set PG_G on the UPAGES that are now in kernel context, and invalidate them when swapping them out. Move the upages object (upobj) from the vmspace to the proc structure. Now that the UPAGES (pcb and kernel stack) are out of user space, make rfork(..RFMEM..) do what was intended by sharing the vmspace entirely via reference counting rather than simply inheriting the mappings.
1997-04-07 07:16:06 +00:00
}
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