Commit Graph

251 Commits

Author SHA1 Message Date
Julian Elischer
297800599a In a threaded process, don't kill off all the other threads until we have a
reasonable chance that the eceve() is going to succeeed. I.e.
wait until we've done the permission checks etc.

MFC after:	1 week
2004-09-21 21:05:13 +00:00
Julian Elischer
ed062c8d66 Refactor a bunch of scheduler code to give basically the same behaviour
but with slightly cleaned up interfaces.

The KSE structure has become the same as the "per thread scheduler
private data" structure. In order to not make the diffs too great
one is #defined as the other at this time.

The KSE (or td_sched) structure is  now allocated per thread and has no
allocation code of its own.

Concurrency for a KSEGRP is now kept track of via a simple pair of counters
rather than using KSE structures as tokens.

Since the KSE structure is different in each scheduler, kern_switch.c
is now included at the end of each scheduler. Nothing outside the
scheduler knows the contents of the KSE (aka td_sched) structure.

The fields in the ksegrp structure that are to do with the scheduler's
queueing mechanisms are now moved to the kg_sched structure.
(per ksegrp scheduler private data structure). In other words how the
scheduler queues and keeps track of threads is no-one's business except
the scheduler's. This should allow people to write experimental
schedulers with completely different internal structuring.

A scheduler call sched_set_concurrency(kg, N) has been added that
notifies teh scheduler that no more than N threads from that ksegrp
should be allowed to be on concurrently scheduled. This is also
used to enforce 'fainess' at this time so that a ksegrp with
10000 threads can not swamp a the run queue and force out a process
with 1 thread, since the current code will not set the concurrency above
NCPU, and both schedulers will not allow more than that many
onto the system run queue at a time. Each scheduler should eventualy develop
their own methods to do this now that they are effectively separated.

Rejig libthr's kernel interface to follow the same code paths as
linkse for scope system threads. This has slightly hurt libthr's performance
but I will work to recover as much of it as I can.

Thread exit code has been cleaned up greatly.
exit and exec code now transitions a process back to
'standard non-threaded mode' before taking the next step.
Reviewed by:	scottl, peter
MFC after:	1 week
2004-09-05 02:09:54 +00:00
John-Mark Gurney
ad3b9257c2 Add locking to the kqueue subsystem. This also makes the kqueue subsystem
a more complete subsystem, and removes the knowlege of how things are
implemented from the drivers.  Include locking around filter ops, so a
module like aio will know when not to be unloaded if there are outstanding
knotes using it's filter ops.

Currently, it uses the MTX_DUPOK even though it is not always safe to
aquire duplicate locks.  Witness currently doesn't support the ability
to discover if a dup lock is ok (in some cases).

Reviewed by:	green, rwatson (both earlier versions)
2004-08-15 06:24:42 +00:00
Colin Percival
56f21b9d74 Rename suser_cred()'s PRISON_ROOT flag to SUSER_ALLOWJAIL. This is
somewhat clearer, but more importantly allows for a consistent naming
scheme for suser_cred flags.

The old name is still defined, but will be removed in a few days (unless I
hear any complaints...)

Discussed with:	rwatson, scottl
Requested by:	jhb
2004-07-26 07:24:04 +00:00
Julian Elischer
aa3c8c02ae White space fix..
diff reduction for upcoming commit.
2004-07-24 04:57:41 +00:00
Alan Cox
ce8da3091f Push down the acquisition and release of the page queues lock into
pmap_remove_pages().  (The implementation of pmap_remove_pages() is
optional.  If pmap_remove_pages() is unimplemented, the acquisition and
release of the page queues lock is unnecessary.)

Remove spl calls from the alpha, arm, and ia64 pmap_remove_pages().
2004-07-13 02:49:22 +00:00
Tim J. Robbins
aa0aa7a113 Move TDF_SA from td_flags to td_pflags (and rename it accordingly)
so that it is no longer necessary to hold sched_lock while
manipulating it.

Reviewed by:	davidxu
2004-06-02 07:52:36 +00:00
David Xu
702ac0f112 Clear KSE thread flags after KSE thread mode is ended. The side effect
of not clearing the flags for execv() syscall will result that a new
program runs in KSE thread mode without enabling it.

Submitted by: tjr
Modified by: davidxu
2004-05-21 14:50:23 +00:00
Alan Cox
59c8bc40ce Utilize sf_buf_alloc() rather than pmap_qenter() (and sometimes
kmem_alloc_wait()) for mapping the image header.  On all machines with a
direct virtual-to-physical mapping and SMP/HTT i386s, this is a clear win.
2004-04-23 03:01:40 +00:00
Alan Cox
148b3f62a9 Use vm_page_hold() rather than vm_page_wire() for short-duration page
wiring.  The reason being that vm_page_hold() is cheaper.
2004-04-11 19:57:11 +00:00
Pawel Jakub Dawidek
2fc0588da2 Remove sysctl kern.ps_argsopen, it is not very useful, one should use
security.bsd.see_other_uids instead.

Discussed with:	phk, rwatson
2004-04-01 00:10:45 +00:00
Peter Wemm
a5bdcb2a2f Make the process_exit eventhandler run without Giant. Add Giant hooks
in the two consumers that need it.. processes using AIO and netncp.
Update docs.  Say that process_exec is called with Giant, but not to
depend on it.  All our consumers can handle it without Giant.
2004-03-14 02:06:28 +00:00
Peter Wemm
37814395c1 Push Giant down a little further:
- no longer serialize on Giant for thread_single*() and family in fork,
  exit and exec
- thread_wait() is mpsafe, assert no Giant
- reduce scope of Giant in exit to not cover thread_wait and just do
  vm_waitproc().
- assert that thread_single() family are not called with Giant
- remove the DROP/PICKUP_GIANT macros from thread_single() family
- assert that thread_suspend_check() s not called with Giant
- remove manual drop_giant hack in thread_suspend_check since we know it
  isn't held.
- remove the DROP/PICKUP_GIANT macros from thread_suspend_check() family
- mark kse_create() mpsafe
2004-03-13 22:31:39 +00:00
Ruslan Ermilov
7700eb86e7 Do what the execve(2) manpage says and enforce what a Strictly
Conforming POSIX application should do by disallowing the argv
argument to be NULL.

PR:		kern/33738
Submitted by:	Marc Olzheim, Serge van den Boom
OK'ed by:	nectar
2004-03-12 21:06:20 +00:00
John Baldwin
8144e3b884 Lock Giant around the single threading code in exec() to satisfy an
assertion in the single threading code.
2004-03-05 22:38:26 +00:00
Peter Wemm
df7c361e64 Checkpoint a hack to enable running i386 libc_r binaries on a 64 bit
kernel.  I'm not happy with it yet - refinements are to come.
This hack allows the kern.ps_strings and kern.usrstack sysctls to respond
to a 32 bit request, such as those coming from emulated i386 binaries.
2004-02-18 00:54:17 +00:00
Bruce Evans
d6c847f378 Fixed some style bugs (mainly, try to always use explicit comparisons with
NULL when checking for null pointers).
2003-12-28 04:37:59 +00:00
Bruce Evans
ca46e90ef4 Fixed some disordering in revs.1.194 and 1,196. Moved the exceve() syscall
function back to near the beginning of the file.  Rev.1.194 moved it into
the middle of auxiliary functions following kern_execve().  Moved the
__mac_execve() syscall function up together with execve().  It was new in
rev1.1.196 and perfectly misplaced after execve().
2003-12-28 04:18:13 +00:00
Alan Cox
34d2675761 Remove GIANT_REQUIRED from exec_unmap_first_page(). 2003-12-27 19:40:03 +00:00
Robert Watson
eca8a663d4 Modify the MAC Framework so that instead of embedding a (struct label)
in various kernel objects to represent security data, we embed a
(struct label *) pointer, which now references labels allocated using
a UMA zone (mac_label.c).  This allows the size and shape of struct
label to be varied without changing the size and shape of these kernel
objects, which become part of the frozen ABI with 5-STABLE.  This opens
the door for boot-time selection of the number of label slots, and hence
changes to the bound on the number of simultaneous labeled policies
at boot-time instead of compile-time.  This also makes it easier to
embed label references in new objects as required for locking/caching
with fine-grained network stack locking, such as inpcb structures.

This change also moves us further in the direction of hiding the
structure of kernel objects from MAC policy modules, not to mention
dramatically reducing the number of '&' symbols appearing in both the
MAC Framework and MAC policy modules, and improving readability.

While this results in minimal performance change with MAC enabled, it
will observably shrink the size of a number of critical kernel data
structures for the !MAC case, and should have a small (but measurable)
performance benefit (i.e., struct vnode, struct socket) do to memory
conservation and reduced cost of zeroing memory.

NOTE: Users of MAC must recompile their kernel and all MAC modules as a
result of this change.  Because this is an API change, third party
MAC modules will also need to be updated to make less use of the '&'
symbol.

Suggestions from:	bmilekic
Obtained from:		TrustedBSD Project
Sponsored by:		DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
Marcel Moolenaar
9ee99eb496 Remove md_bspstore from the MD fields of struct thread. Now that
the backing store is at a fixed address, there's no need for a
per-thread variable.
2003-10-21 01:13:49 +00:00
Marcel Moolenaar
bab1f05277 Put the RSE backing store at a fixed address. This change is triggered
by libguile that needs to know the base of the RSE backing store. We
currently do not export the fixed address to userland by means of a
sysctl so user code needs to hardcode it for now. This will be revisited
later.

The RSE backing store is now at the bottom of region 4. The memory stack
is at the top of region 4. This means that the whole region is usable
for the stacks, giving a 61-bit stack space.

Port: lang/guile (depended of x11/gnome2)
2003-10-20 05:34:10 +00:00
Alan Cox
6ec2fca505 Eliminate some unnecessary uses of the vm page queues lock around the
vm page's valid field.  This field is being synchronized using the
containing vm object's lock.
2003-10-04 22:47:20 +00:00
Marcel Moolenaar
c31f2280ed Remove the regstkpages sysctl variable. We have a growable register
stack now.
2003-09-27 23:07:47 +00:00
Marcel Moolenaar
fd75d71049 Part 2 of implementing rstacks: add the ability to create rstacks and
use the ability on ia64 to map the register stack. The orientation of
the stack (i.e. its grow direction) is passed to vm_map_stack() in the
overloaded cow argument. Since the grow direction is represented by
bits, it is possible and allowed to create bi-directional stacks.
This is not an advertised feature, more of a side-effect.

Fix a bug in vm_map_growstack() that's specific to rstacks and which
we could only find by having the ability to create rstacks: when
the mapped stack ends at the faulting address, we have not actually
mapped the faulting address. we need to include or cover the faulting
address.

Note that at this time mmap(2) has not been extended to allow the
creation of rstacks by processes. If such a need arises, this can
be done.

Tested on: alpha, i386, ia64, sparc64
2003-09-27 22:28:14 +00:00
Peter Wemm
c460ac3a00 Add sysentvec->sv_fixlimits() hook so that we can catch cases on 64 bit
systems where the data/stack/etc limits are too big for a 32 bit process.

Move the 5 or so identical instances of ELF_RTLD_ADDR() into imgact_elf.c.

Supply an ia32_fixlimits function.  Export the clip/default values to
sysctl under the compat.ia32 heirarchy.

Have mmap(0, ...) respect the current p->p_limits[RLIMIT_DATA].rlim_max
value rather than the sysctl tweakable variable.  This allows mmap to
place mappings at sensible locations when limits have been reduced.

Have the imgact_elf.c ld-elf.so.1 placement algorithm use the same
method as mmap(0, ...) now does.

Note that we cannot remove all references to the sysctl tweakable
maxdsiz etc variables because /etc/login.conf specifies a datasize
of 'unlimited'.  And that causes exec etc to fail since it can no
longer find space to mmap things.
2003-09-25 01:10:26 +00:00
Poul-Henning Kamp
a8d43c90af Add a "int fd" argument to VOP_OPEN() which in the future will
contain the filedescriptor number on opens from userland.

The index is used rather than a "struct file *" since it conveys a bit
more information, which may be useful to in particular fdescfs and /dev/fd/*

For now pass -1 all over the place.
2003-07-26 07:32:23 +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
8630c1173e Add vm object locking to various pagers' "get pages" methods, i386 stack
management functions, and a u area management function.
2003-06-13 03:02:28 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Alan Cox
06fa71cdcc Update the vm object and page locking in exec_map_first_page(). Mark the
one still anticipated change with XXX.  Otherwise, this function is done.
2003-06-09 19:37:14 +00:00
Alan Cox
fd0cc9a862 Lock the vm object when performing vm_page_grab(). 2003-06-08 07:14:30 +00:00
John Baldwin
90af4afacb - Merge struct procsig with struct sigacts.
- Move struct sigacts out of the u-area and malloc() it using the
  M_SUBPROC malloc bucket.
- Add a small sigacts_*() API for managing sigacts structures: sigacts_alloc(),
  sigacts_free(), sigacts_copy(), sigacts_share(), and sigacts_shared().
- Remove the p_sigignore, p_sigacts, and p_sigcatch macros.
- Add a mutex to struct sigacts that protects all the members of the struct.
- Add sigacts locking.
- Remove Giant from nosys(), kill(), killpg(), and kern_sigaction() now
  that sigacts is locked.
- Several in-kernel functions such as psignal(), tdsignal(), trapsignal(),
  and thread_stopped() are now MP safe.

Reviewed by:	arch@
Approved by:	re (rwatson)
2003-05-13 20:36:02 +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
John Baldwin
75b8b3b25c Replace the at_fork, at_exec, and at_exit functions with the slightly more
flexible process_fork, process_exec, and process_exit eventhandlers.  This
reduces code duplication and also means that I don't have to go duplicate
the eventhandler locking three more times for each of at_fork, at_exec, and
at_exit.

Reviewed by:	phk, jake, almost complete silence on arch@
2003-03-24 21:15:35 +00:00
John Baldwin
a5881ea55a - Cache a reference to the credential of the thread that starts a ktrace in
struct proc as p_tracecred alongside the current cache of the vnode in
  p_tracep.  This credential is then used for all later ktrace operations on
  this file rather than using the credential of the current thread at the
  time of each ktrace event.
- Now that we have multiple ktrace-related items in struct proc that are
  pointers, rename p_tracep to p_tracevp to make it less ambiguous.

Requested by:	rwatson (1)
2003-03-13 18:24:22 +00:00
Julian Elischer
ac2e415327 Change the process flags P_KSES to be P_THREADED.
This is just a cosmetic change but I've been meaning to do it for about a year.
2003-02-27 02:05:19 +00:00
Warner Losh
a163d034fa Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
Jeff Roberson
5215b1872f - Split the struct kse into struct upcall and struct kse. struct kse will
soon be visible only to schedulers.  This greatly simplifies much the
   KSE code.

Submitted by:	davidxu
2003-02-17 05:14:26 +00:00
Julian Elischer
6f8132a867 Reversion of commit by Davidxu plus fixes since applied.
I'm not convinced there is anything major wrong with the patch but
them's the rules..

I am using my "David's mentor" hat to revert this as he's
offline for a while.
2003-02-01 12:17:09 +00:00
David Xu
0dbb100b9b Move UPCALL related data structure out of kse, introduce a new
data structure called kse_upcall to manage UPCALL. All KSE binding
and loaning code are gone.

A thread owns an upcall can collect all completed syscall contexts in
its ksegrp, turn itself into UPCALL mode, and takes those contexts back
to userland. Any thread without upcall structure has to export their
contexts and exit at user boundary.

Any thread running in user mode owns an upcall structure, when it enters
kernel, if the kse mailbox's current thread pointer is not NULL, then
when the thread is blocked in kernel, a new UPCALL thread is created and
the upcall structure is transfered to the new UPCALL thread. if the kse
mailbox's current thread pointer is NULL, then when a thread is blocked
in kernel, no UPCALL thread will be created.

Each upcall always has an owner thread. Userland can remove an upcall by
calling kse_exit, when all upcalls in ksegrp are removed, the group is
atomatically shutdown. An upcall owner thread also exits when process is
in exiting state. when an owner thread exits, the upcall it owns is also
removed.

KSE is a pure scheduler entity. it represents a virtual cpu. when a thread
is running, it always has a KSE associated with it. scheduler is free to
assign a KSE to thread according thread priority, if thread priority is changed,
KSE can be moved from one thread to another.

When a ksegrp is created, there is always N KSEs created in the group. the
N is the number of physical cpu in the current system. This makes it is
possible that even an userland UTS is single CPU safe, threads in kernel still
can execute on different cpu in parallel. Userland calls kse_create to add more
upcall structures into ksegrp to increase concurrent in userland itself, kernel
is not restricted by number of upcalls userland provides.

The code hasn't been tested under SMP by author due to lack of hardware.

Reviewed by: julian
2003-01-26 11:41:35 +00:00
Alfred Perlstein
44956c9863 Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
Robert Watson
ec35c2af68 Perform VOP_GETATTR() before mac_check_vnode_exec() so that
the cached attributes are available to MAC modules.

Submitted by:   mike halderman <mrh@nosc.mil>
Obtained from:	TrustedBSD Project
2003-01-21 03:26:28 +00:00
Matthew Dillon
3db161e079 It is possible for an active aio to prevent shared memory from being
dereferenced when a process exits due to the vmspace ref-count being
bumped.  Change shmexit() and shmexit_myhook() to take a vmspace instead
of a process and call it in vmspace_dofree().  This way if it is missed
in exit1()'s early-resource-free it will still be caught when the zombie is
reaped.

Also fix a potential race in shmexit_myhook() by NULLing out
vmspace->vm_shm prior to calling shm_delete_mapping() and free().

MFC after:	7 days
2003-01-13 23:04:32 +00:00
David Xu
45f603e21c Clear some KSE fields after kse mode was turned off. 2003-01-07 06:56:43 +00:00
Jake Burkholder
5dadd17b08 Add a sysctl to get the vm protections for the stack of the current process.
On architectures with a non-executable stack, eg sparc64, this is used by
libgcc to determine at runtime if its necessary to enable execute permissions
on a region of the stack which will be used to execute code, allowing the
call to mprotect to be avoided if the kernel is configured to map the stack
executable.
2003-01-04 07:54:23 +00:00
Alfred Perlstein
c522c1bf4b fdcopy() only needs a filedesc pointer. 2003-01-01 01:19:31 +00:00
Alan Cox
ee113343eb Hold the page queues lock when performing vm_page_busy(). 2002-12-18 20:16:22 +00:00
Alfred Perlstein
b80521fee5 remove syscallarg().
Suggested by: peter
2002-12-14 02:07:32 +00:00
Robert Drehmel
d1989db545 To avoid sleeping with all sorts of resources acquired (the reported
problem was a locked directory vnode), do not give the process a chance
to sleep in state "stopevent" (depends on the S_EXEC bit being set in
p_stops) until most resources have been released again.

Approved by:	re
2002-11-26 17:30:55 +00:00