Commit Graph

148 Commits

Author SHA1 Message Date
Mike Makonnen
8689793bfb kse_thr_interrupt should target the thread, specifically.
Requested by:	davidxu
2003-07-04 01:41:32 +00:00
Mike Makonnen
c197abc49a Signals sent specifically to a particular thread must
be delivered to that thread, regardless of whether it
has it masked or not.

Previously, if the targeted thread had the signal masked,
it would be put on the processes' siglist. If
another thread has the signal umasked or unmasks it before
the target, then the thread it was intended for would never
receive it.

This patch attempts to solve the problem by requiring callers
of tdsignal() to say whether the signal is for the thread or
for the process. If it is for the process, then normal processing
occurs and any thread that has it unmasked can receive it.
But if it is destined for a specific thread, it is put on
that thread's pending list regardless of whether it is currently
masked or not.

The new behaviour still needs more work, though.  If the signal
is reposted for some reason it is always posted back to the
thread that handled it because the information regarding the
target of the signal has been lost by then.

Reviewed by:	jdp, jeff, bde (style)
2003-07-03 19:09:59 +00:00
David Xu
df9c6cda37 Fix typo. 2003-06-30 10:04:04 +00:00
Marcel Moolenaar
4e4422d4d4 Don't use fuword() and suword() on struct members of type int. This
happens to work on 32-bit platforms as sizeof(long)=sizeof(int), but
wrecks all kinds of havoc (garbage reads, corrupting writes and
misaligned loads/stores) on 64-bit architectures.
The fix for now is to use fuword32() and suword32() and change the
type of the applicable int fields to int32. This is to make it
explicit that we depend on these fields being 32-bit. We may want
to revisit this later.

Reviewed by: deischen
2003-06-28 19:45:15 +00:00
David Xu
9dde3bc999 o Change kse_thr_interrupt to allow send a signal to a specified thread,
or unblock a thread in kernel, and allow UTS to specify whether syscall
  should be restarted.
o Add ability for UTS to monitor signal comes in and removed from process,
  the flag PS_SIGEVENT is used to indicate the events.
o Add a KMF_WAITSIGEVENT for KSE mailbox flag, UTS call kse_release with
  this flag set to wait for above signal event.
o For SA based thread, kernel masks all signal in its signal mask, let
  UTS to use kse_thr_interrupt interrupt a thread, and install a signal
  frame in userland for the thread.
o Add a tm_syncsig in thread mailbox, when a hardware trap occurs,
  it is used to deliver synchronous signal to userland, and upcall
  is schedule, so UTS can process the synchronous signal for the thread.

Reviewed by: julian (mentor)
2003-06-28 08:29:05 +00:00
David Xu
ab78d4d641 cpu_set_upcall_kse needs to access userspace, release schedule lock
before calling it for bound thread. To avoid this problem, change
thread_schedule_upcall to not put new thread on run queue, let caller
do it, so we can tweak the new thread before setting it to run.

Reported by: pho
2003-06-20 09:12:12 +00:00
David Xu
4184d79115 Forgot to commit code to disable creating a bound thread in same
group again except first kse_create syscall.

Noticed by: julian
2003-06-16 23:46:41 +00:00
David Xu
075102cc4e Reset ncpus to 1 for bound thread group since there is only one
thread in such group.
Change message text from kse_rel to kserel, it is better displayed
in top.
2003-06-16 13:14:52 +00:00
David Xu
cd4f6ebb13 1. Add code to support bound thread. when blocked, a bound thread never
schedules an upcall. Signal delivering to a bound thread is same as
   non-threaded process. This is intended to be used by libpthread to
   implement PTHREAD_SCOPE_SYSTEM thread.
2. Simplify kse_release() a bit, remove sleep loop.
2003-06-15 12:51:26 +00:00
David Xu
1d5a24bec6 1. Migrate TDF_UPCALLING from td_flags to td_pflags.
2. Add a flag TDF_SA, it will be used to distinguish SA
   based thread from bound thread.
2003-06-15 03:18:58 +00:00
David Xu
0e2a4d3aeb Rename P_THREADED to P_SA. P_SA means a process is using scheduler
activations.
2003-06-15 00:31:24 +00:00
Alan Cox
49a2507bd1 Migrate the thread stack management functions from the machine-dependent
to the machine-independent parts of the VM.  At the same time, this
introduces vm object locking for the non-i386 platforms.

Two details:

1. KSTACK_GUARD has been removed in favor of KSTACK_GUARD_PAGES.  The
different machine-dependent implementations used various combinations
of KSTACK_GUARD and KSTACK_GUARD_PAGES.  To disable guard page, set
KSTACK_GUARD_PAGES to 0.

2. Remove the (unnecessary) clearing of PG_ZERO in vm_thread_new.  In
5.x, (but not 4.x,) PG_ZERO can only be set if VM_ALLOC_ZERO is passed
to vm_page_alloc() or vm_page_grab().
2003-06-14 23:23:55 +00:00
David Xu
7677ce18b8 Fix error in my last commit. Correctly maintain p_maxthrwaits and unlock
sched_lock.
2003-06-11 01:08:33 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
David Xu
36407bec4f If there are signals delivered to current thread, breaks out of loop,
userret() will be called again by ast() and thread_userret() will be
called again by userret().

Reported by: tegge
2003-06-10 02:21:32 +00:00
David Xu
b0bd5f38a6 thread_signal_add now is called with ps_mtx held, unlock it before
calling copyin.
2003-06-06 02:17:38 +00:00
Marcel Moolenaar
11e0f8e16d Change the second (and last) argument of cpu_set_upcall(). Previously
we were passing in a void* representing the PCB of the parent thread.
Now we pass a pointer to the parent thread itself.
The prime reason for this change is to allow cpu_set_upcall() to copy
(parts of) the trapframe instead of having it done in MI code in each
caller of cpu_set_upcall(). Copying the trapframe cannot always be
done with a simply bcopy() or may not always be optimal that way. On
ia64 specifically the trapframe contains information that is specific
to an entry into the kernel and can only be used by the corresponding
exit from the kernel. A trapframe copied verbatim from another frame
is in most cases useless without some additional normalization.

Note that this change removes the assignment to td->td_frame in some
implementations of cpu_set_upcall(). The assignment is redundant.
A previous call to cpu_thread_setup() already did the exact same
assignment. An added benefit of removing the redundant assignment is
that we can now change td_pcb without nasty side-effects.

This change officially marks the ability on ia64 for 1:1 threading.

Not tested on: amd64, powerpc
Compile & boot tested on: alpha, sparc64
Functionally tested on: i386, ia64
2003-06-04 21:13:21 +00:00
Julian Elischer
2b035cbe5a Remove un-needed code.
Don't copyin() data we are about to overwrite.
Add a flag to tell userland that KSE is officially "DONE" with the
mailbox and has gone away.

Obtained from:	davidxu@
2003-06-04 00:12:57 +00:00
Marcel Moolenaar
bf822712f7 Remove the ia64 hackery in threadinit() that was needed to work around
the lameness of the kstack code. The EPC overhaul de-lame-ified the
kstack code by removing the need for contigmalloc(). We can now
allocate stacks using malloc(). We probably want to make the stacks
swappable as well so that we can make it MI. But that's another story.
2003-06-01 05:57:58 +00:00
Poul-Henning Kamp
670966596b Remove unused variable(s).
Found by:       FlexeLint
2003-05-31 20:29:34 +00:00
Marcel Moolenaar
f2c49dd248 Revamp of the syscall path, exception and context handling. The
prime objectives are:
o  Implement a syscall path based on the epc inststruction (see
   sys/ia64/ia64/syscall.s).
o  Revisit the places were we need to save and restore registers
   and define those contexts in terms of the register sets (see
   sys/ia64/include/_regset.h).

Secundairy objectives:
o  Remove the requirement to use contigmalloc for kernel stacks.
o  Better handling of the high FP registers for SMP systems.
o  Switch to the new cpu_switch() and cpu_throw() semantics.
o  Add a good unwinder to reconstruct contexts for the rare
   cases we need to (see sys/contrib/ia64/libuwx)

Many files are affected by this change. Functionally it boils
down to:
o  The EPC syscall doesn't preserve registers it does not need
   to preserve and places the arguments differently on the stack.
   This affects libc and truss.
o  The address of the kernel page directory (kptdir) had to
   be unstaticized for use by the nested TLB fault handler.
   The name has been changed to ia64_kptdir to avoid conflicts.
   The renaming affects libkvm.
o  The trapframe only contains the special registers and the
   scratch registers. For syscalls using the EPC syscall path
   no scratch registers are saved. This affects all places where
   the trapframe is accessed. Most notably the unaligned access
   handler, the signal delivery code and the debugger.
o  Context switching only partly saves the special registers
   and the preserved registers. This affects cpu_switch() and
   triggered the move to the new semantics, which additionally
   affects cpu_throw().
o  The high FP registers are either in the PCB or on some
   CPU. context switching for them is done lazily. This affects
   trap().
o  The mcontext has room for all registers, but not all of them
   have to be defined in all cases. This mostly affects signal
   delivery code now. The *context syscalls are as of yet still
   unimplemented.

Many details went into the removal of the requirement to use
contigmalloc for kernel stacks. The details are mostly CPU
specific and limited to exception_save() and exception_restore().
The few places where we create, destroy or switch stacks were
mostly simplified by not having to construct physical addresses
and additionally saving the virtual addresses for later use.

Besides more efficient context saving and restoring, which of
course yields a noticable speedup, this also fixes the dreaded
SMP bootup problem as a side-effect. The details of which are
still not fully understood.

This change includes all the necessary backward compatibility
code to have it handle older userland binaries that use the
break instruction for syscalls. Support for break-based syscalls
has been pessimized in favor of a clean implementation. Due to
the overall better performance of the kernel, this will still
be notived as an improvement if it's noticed at all.

Approved by: re@ (jhb)
2003-05-16 21:26:42 +00:00
David Xu
c6523b663f Fix compiling problem, p_tracee is in my local repository for
threaded process debugging, not ready for this time.
2003-05-01 12:16:06 +00:00
David Xu
1ecc645634 Drop Giant lock before suspended, pick up it after resumed.
thread_suspend_check() is used in exit1() which still needs
Giant lock.
2003-05-01 07:29:25 +00:00
Peter Wemm
cb1f265c60 AMD64 uses the new-style cpu_switch()/cpu_throw() calling conventions. 2003-04-30 21:45:03 +00:00
David Xu
5c29a450ae Increase some default values. 2003-04-30 01:18:29 +00:00
David Xu
5073e68fa3 unlock sched_lock at right time. 2003-04-27 04:32:40 +00:00
Daniel Eischen
1328e1c4be Add an argument to get_mcontext() which specified whether the
syscall return values should be cleared.  The system calls
getcontext() and swapcontext() want to return 0 on success
but these contexts can be switched to at a later time so
the return values need to be cleared in the saved register
sets.  Other callers of get_mcontext() would normally want
the context without clearing the return values.

Remove the i386-specific context saving from the KSE code.
get_mcontext() is not i386-specific any more.

Fix a bad pointer in the alpha get_mcontext() code.  The
context was being bcopy()'d from &td->tf_frame, but tf_frame
is itself a pointer, so the thread was being copied instead.
Spotted by jake.

Glanced at by:  jake
Reviewed by:    bde (months ago)
2003-04-25 01:50:30 +00:00
John Baldwin
112afcb232 - Protect p_numthreads with the sched_lock.
- Protect p_singlethread with both the sched_lock and the proc lock.
- Protect p_suspcount with the proc lock.
2003-04-23 18:46:51 +00:00
John Baldwin
a6f37ac9d6 - Mark the kse_purge_group() and kse_purge() definitions static to match
their prototypes.
- Remove sched_lock locking from kse_purge() as all callers already lock
  the sched_lock before calling it.
- Hold the proc lock slightly longer to protect P_SHOULDSTOP().
2003-04-22 19:47:55 +00:00
David Xu
11b20c685b Fix lock order reversal problem. 2003-04-21 14:42:04 +00:00
David Xu
1ecb38a365 Introduce two flags to control upcall behaviour:
o KMF_NOUPCALL
	Ask kse_release to not return to userland upcall entry, but instead
	direct returns to userland by using current thread's stack and return
	address on stack. This flags is intended to be used by UTS in critical
	region to wait another UTS thread to leave critical region, by using
	kse_release with this flag to avoid spinnng and burning CPU. Also this
	flags can be used by UTS to poll completed context when there is nothing
	to do in userland and needn't restart from its entry like normal upcall.

o KMF_NOCOMPLETED
	Ask kernel to not bring completed thread contexts back to userland when
	doing upcall, this flags is intend to be used with above flag when an
	upcall thread is in critical region and can not process completed contexts
	at that time.

Tested by: deischen
2003-04-21 07:27:59 +00:00
David Xu
95bee4c365 Test next upcall time correctly. 2003-04-19 06:16:04 +00:00
David Xu
588257e810 Use correct thread pointer. 2003-04-19 04:39:10 +00:00
John Baldwin
889a6b5845 Use the proc lock to protect p_singlethread and a P_WEXIT test. This
fixes a couple of potential KSE panics on non-i386 arch's that weren't
holding the proc lock when calling thread_exit().
2003-04-18 20:20:00 +00:00
Julian Elischer
d3a0bd78a8 Add a thread_unlink() and use it.
It could also be used twice in kern_thr.c but that's owned by jeff
so I'l let him change it when he's next there.
2003-04-18 00:16:13 +00:00
John Baldwin
94df4b8584 Protect td_sigmask with the proc lock. 2003-04-17 22:21:57 +00:00
Julian Elischer
060563ec50 Move the _oncpu entry from the KSE to the thread.
The entry in the KSE still exists but it's purpose will change a bit
when we add the ability to lock a KSE to a cpu.
2003-04-10 17:35:44 +00:00
David Xu
36f7b36f8a Inherit blocked thread's context for upcall thread. 2003-04-08 07:45:56 +00:00
Peter Wemm
cc66ebe2a9 Commit a partial lazy thread switch mechanism for i386. it isn't as lazy
as it could be and can do with some more cleanup.  Currently its under
options LAZY_SWITCH.  What this does is avoid %cr3 reloads for short
context switches that do not involve another user process.  ie: we can
take an interrupt, switch to a kthread and return to the user without
explicitly flushing the tlb.  However, this isn't as exciting as it could
be, the interrupt overhead is still high and too much blocks on Giant
still.  There are some debug sysctls, for stats and for an on/off switch.

The main problem with doing this has been "what if the process that you're
running on exits while we're borrowing its address space?" - in this case
we use an IPI to give it a kick when we're about to reclaim the pmap.

Its not compiled in unless you add the LAZY_SWITCH option.  I want to fix a
few more things and get some more feedback before turning it on by default.

This is NOT a replacement for Bosko's lazy interrupt stuff.  This was more
meant for the kthread case, while his was for interrupts.  Mine helps a
little for interrupts, but his helps a lot more.

The stats are enabled with options SWTCH_OPTIM_STATS - this has been a
pseudo-option for years, I just added a bunch of stuff to it.

One non-trivial change was to select a new thread before calling
cpu_switch() in the first place.  This allows us to catch the silly
case of doing a cpu_switch() to the current process.  This happens
uncomfortably often.  This simplifies a bit of the asm code in cpu_switch
(no longer have to call choosethread() in the middle).  This has been
implemented on i386 and (thanks to jake) sparc64.  The others will come
soon.  This is actually seperate to the lazy switch stuff.

Glanced at by:  jake, jhb
2003-04-02 23:53:30 +00:00
Jeff Roberson
2c10d16a4b - Borrow the KSE single threading code for exec and exit. We use the check
if (p->p_numthreads > 1) and not a flag because action is only necessary
   if there are other threads.  The rest of the system has no need to
   identify thr threaded processes.
 - In kern_thread.c use thr_exit1() instead of thread_exit() if P_THREADED
   is not set.
2003-04-01 01:26:20 +00:00
Jeff Roberson
4093529dee - Move p->p_sigmask to td->td_sigmask. Signal masks will be per thread with
a follow on commit to kern_sig.c
 - signotify() now operates on a thread since unmasked pending signals are
   stored in the thread.
 - PS_NEEDSIGCHK moves to TDF_NEEDSIGCHK.
2003-03-31 22:49:17 +00:00
John Baldwin
16088e4a88 Check for the PS_NEEDSIGCHK flag in the right flags field. 2003-03-28 18:08:57 +00:00
David Xu
6ce75196ce Adjust code for userland preemptive. Userland can set a quantum in
kse_mailbox to schedule an upcall, this is useful for userland timeout
routine, for example pthread_cond_timedwait().

Also extract upcall scheduling code from kse_reassign and create
a new function called thread_switchout to include these code.

Reviewed by: julain
2003-03-19 05:49:38 +00:00
David Xu
9a4b78c9da Export current time when returning from never blocked syscall. 2003-03-14 03:52:16 +00:00
David Xu
661db6da35 Lock proc lock before changing p_flag. 2003-03-11 03:16:02 +00:00
David Xu
21e0492ab1 Fix signal delivering bug for threaded process. 2003-03-11 02:59:50 +00:00
David Xu
e574e444e0 Fix threaded process job control bug. SMP tested.
Reviewed by: julian
2003-03-11 00:07:53 +00:00
David Xu
b4508d7d3f Lock sched_lock before modifying td_flags. 2003-03-08 04:09:04 +00:00
David Xu
9948c47f0e Check kse group limit before linking new ksegrp. 2003-02-28 15:57:33 +00:00
David Xu
3b3df40fc4 Release sched_lock before calling upcall_free. 2003-02-27 05:42:01 +00:00