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)
lock held (_thr_sched_switch_unlocked()) and use this to avoid
dropping the scheduler lock and having the scheduler retake the
same lock again.
Add a better way of detecting if a low-level lock is in use.
When switching out a thread due to blocking in the UTS, don't
switch to the KSE's scheduler stack only to switch back to
another thread. If possible switch to the new thread directly
from the old thread and avoid the overhead of the extra
context switch.
Check for pending signals on a thread when entering the scheduler
and add them to the threads signal frame. This includes some
other minor signal fixes.
Most of this was a joint effor between davidxu and myself.
Reviewed by: davidxu
Approved by: re@ (blanket for libpthread)
Fixes a problem where directory entries could show up twice: once
on the top layer of the union stack, and once on the bottom layer.
Approved by: re (rwatson)
of pthread_cond_timedwait() is moved into cond_wait_common().
Pthread_cond_wait() and pthread_cond_timedwait() are now wrappers around
this function. Previously, the former called the latter with the abstime
pointing to 0 time. This violated Posix semantics should an application
have reason to call it with that argument because instead or returning
immediately it would have waited indefinitely for the cv to be signaled.
Approved by: markm/mentor, re/blanket libthr
Reviewed by: jeff
respect to other threads and signal handlers by moving to
the _thread_critical_enter/exit functions.
o Introduce an static function, testcancel(), that is used by
the other functions in this module. This allows it to make
locking assumptions that the top-level functions can't.
o Rework the code flow a bit to reduce indentation levels.
Approved by: markm/mentor, re/blanket libthr
Reviewed by: jeff
Those who really need this information can find it in the include file.
* Include a succinct description of the st_birthtime field.
Approved by: re (bmah)
- hosts_ctl(3), hosts_access(3), request_init(3),
request_set(3).
PR: docs/52000
Submitted by: Simon L. Nielsen <simon@nitro.dk>
Approved and Reviewed by: des (mentor), re (scottl)
- strip out the nasty PIC_PROLOGUE/EPILOGUE stuff, since we dont have
to lose a register in PIC mode anymore (we use %rip-relative addressing).
- update for C register argument passing conventions.
- convert 32 bit to 64 bit register sizes etc.
Note that the syscall instruction clobbers %rcx, which is inconvenient
because it is the fourth syscall argument, so we use %r10 (another scratch
register) for the 4th syscall arg instead (I picked %r10 to be the same as
NetBSD). int 0x80 is still possible though, and it uses %rcx as usual.
Note that the syscall style syscall does *NOT* preserve all the registers,
unlike int 0x80. We do not preserve the scratch registers except for
%rdi and %rsi. int 0x80 does preserve everything but the return values.
technique) so that we don't wind up calling into an application's
version if the application defines them.
Inspired by: qpopper's interfering and buggy version of strlcpy
a thread lock).
Better protect access to thread state while searching for
threads to handle a signal.
Better protect access to process pending signals while processing
a thread in sigwait().
Submitted by: davidxu
KSEs when it's thread exits; allow the GC handler to do that.
o Make spinlock/spinlock critical regions.
The following were submitted by davidxu
o Alow thr_switch() to take a null mailbox argument.
o Better protect cancellation checks.
o Don't set KSE specific data when creating new KSEs; rely on the
first upcall of the KSE to set it.
o Add the ability to set the maximum concurrency level and do this
automatically. We should have a way to enable/disable this with
some sort of tunable because some applications may not want this
to be the default.
o Hold the scheduling lock across thread switch calls.
o If scheduling of a thread fails, make sure to remove it from the list
of active threads.
o Better protect accesses to a joining threads when the target thread is
exited and detached.
o Remove some macro definitions that are now provided by <sys/kse.h>.
o Don't leave the library in threaded mode if creation of the initial
KSE fails.
o Wakeup idle KSEs when there are threads ready to run.
o Maintain the number of threads active in the priority queue.
While I'm here, use the TAILQ_FOREACH macro instead of a more
manual method which was inherited from libc_r (so we could
remove elements from the list which isn't needed for libpthread).
Submitted by: Kazuaki Oda <kaakun@highway.ne.jp>
setgrent, and endgrent also. (The previous NSS implementation used to
simply twiddle the internal data of the various modules directly.)
A symptom (group list set incorrectly in sshd) was
Reported by: Glenn Johnson <gjohnson@srrc.ars.usda.gov>
Sponsored by: DARPA, Network Associates Laboratories
idea to re-initialize `struct passwd', because e.g. pw_class might
get set by one module, but not by another. Add another call to the
internal pwd_init function to accomplish this.
Sponsored by: DARPA, Network Associates Laboratories
password must necessarily have an empty pwd->pw_passwd. Also add a check
that prevents users from setting a blank password unless the nullok option
was specified. Root is still allowed to give anyone a blank password.
Correct a bug that should have wreaked havoc everywhere, but for
some reason only bit unlucky people who use `-march' optimizations.
The compiler cannot assist one in distinguishing between the two
function calls below.
int nsdispatch(void *, ...);
void *discard;
nsdispatch(&discard, ...); /* correct .. no, really! */
nsdispatch(discard, ...); /* Boom */
Robin provided me with a debugging environment in which I could see
what was going on.
Badness when using CPUTYPE was
Reported by: "Robin P. Blanchard" <Robin.Blanchard@gactr.uga.edu>
Reported by: nork
Sponsored by: DARPA, Network Associates Laboratories
provided by Sergey A. Osokin <osa@freebsd.org.ru>.
In order to test this on a single CPU machine, you need to:
sysctl kern.threads.debug=1
sysctl kern.threads.virtual_cpu=2
lock level is 0. Thus far, the threads implementation doesn't use
mutexes or condition variables so the lock level should be 0.
Save the return value when trying to schedule a new thread and
use this to return an error from pthread_create().
Change the max sleep time for an idle KSE to 1 minute from 2 minutes.
Maintain a count of the number of KSEs within a KSEG.
With these changes scope system threads seem to work, but heavy
use of them crash the kernel (supposedly VM bugs).
An incorrectly-sized allocation was being made due to an incorrect
argument to the `sizeof' operator. Obvious, because it violated the
`foo = malloc(sizeof(*foo))' idiom. Hard-to-see, because it was a
missing `*' (`*p' versus `**p').
Resulting failure was
Reported by: ache
Sponsored by: DARPA, Network Associates Laboratories
privileges. To do so may cause the NIS server to log spurious and
annoying `access denied' messages.
Reported by: Philip Paeps <philip@paeps.cx>
Sponsored by: DARPA, Network Associates Laboratories
to be instances where the kernel doesn't properly save and/or
restore it.
Use noupcall and nocompleted flags in the KSE mailbox. These
require kernel changes to work which will be committed sometime
later. Things still work without the changes.
Remove the general kse entry function and use two different
functions -- one for scope system threads and one for scope
process threads. The scope system function is not yet enabled
and we use the same function for all threads at the moment.
Keep a copy of the KSE stack for the case that a KSE runs
a scope system thread and uses the same stack as the thread
(no upcalls are generated, so a separate stack isn't needed).
This isn't enabled yet.
Use a separate field for the KSE waiting flag. It isn't
correct to use the mailbox flags field.
The following fixes were provided by David Xu:
o Initialize condition variable locks with thread versions
of the low-level locking functions instead of the kse versions.
o Enable threading before creating the first thread instead
of after.
o Don't enter critical regions when trying to malloc/free
or call functions that malloc/free.
o Take the scheduling lock when inheriting thread attributes.
o Check the attribute's stack pointer instead of the
attributes stack size for null when allocating a
thread's stack.
o Add a kseg reinit function so we don't have to destroy and
then recreate the same lock.
o Check the return value of kse_create() and return an
appropriate error if it fails.
o Don't forget to destroy a thread's locks when freeing it.
o Examine the correct flags word for checking to see if
a thread is in a synchronization queue.
Things should now work on an SMP kernel.
Note that the tp register (r13) is reserved as the TLS pointer in
the same way that that gp register (r1) is reserved as the global
pointer. This implementation uses the tp register to point to the
thread structure used by the threads implementation. This is not
in violation with the runtime specification provided the TLS is
a fixed distance from the thread structure. This is only an issue
when code used the __thread keyword to create TLS. This is not
supported at the moment.
in the mac.3 library man page. They were already cross-referenced
at the end of the man page, just not explicitly listed here.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
libthr. No changes were made to libpthread by request of deischen,
who will soon commit a real implementation for that library.
PR: standards/50848
Submitted by: Sergey A. Osokin <osa@freebsd.org.ru>
MFC after: 1 week
would result in an incorrectly terminated grouplist.
login(1) crashes
Reported by: Morten Rodal <morten@rodal.no>,
Matthias Schuendehuette <msch@snafu.de>
string was an incredibly dumb idea (of course it will be changed by an
NSS module on success!). Use a static empty string instead.
Sponsored by: DARPA, Network Associates Laboratories
may not fill in all fields, and in the case of string fields, this could
cause trouble for applications. (The only likely example is `pw_class',
because this field is not used by all modules in all cases.)
Move initialization of struct passwd from module-specific code to the
dispatch code.
The problem of a NULL pw_class was
Noticed by: Philip Paeps <philip@paeps.cx>
and the c^Htrusty ssh(1) command.
Déjà vu by: getpwent.c revision 1.56
Sponsored by: DARPA, Network Associates Laboratories
at least one consumer outside of libc and pwd_mkdb.
Adjust the versioning in libc and pwd_mkdb accordingly.
named was the application affected, and that fact was first
Reported by: Zherdev Anatoly <tolyar@mx.ru>
Sponsored by: DARPA, Network Associates Laboratories
environment. This includes support for multiple KSEs and KSEGs.
The ability to create more than 1 KSE via pthread_setconcurrency()
is in the works as well as support for PTHREAD_SCOPE_SYSTEM threads.
Those should come shortly.
There are still some known issues which davidxu and I are working
on, but it'll make it easier for us by committing what we have.
This library now passes all of the ACE tests that libc_r passes
with the exception of one. It also seems to work OK with KDE
including konqueror, kwrite, etc. I haven't been able to get
mozilla to run due to lack of java plugin, so I'd be interested
to see how it works with that.
Reviewed by: davidxu
family of functions using the new nsdispatch(3) core. Remove
arbitrary size limits when using the thread-safe versions.
= Re-implement the traditional getpwent(3)/getgrent(3) functions on
top of the thread-safe versions.
= Update the on-disk format of the hashed version of the passwd(5)
databases to allow for versioned entries. The legacy version is
`3'. (Don't ask.)
= Add support for version `4' entries in the passwd(5) database.
Entries in this format are identical to version 3 entries except
that all integers are stored as 32-bit integers in network byte
order (big endian).
= pwd_mkdb is updated to generate both version 3 and version 4
entries.
Sponsored by: DARPA, Network Associates Laboratories
may be built into libc (`static NSS modules') or dynamically loaded
via dlopen (`dynamic NSS modules'). Modules are loaded/initialized
at configuration time (i.e. when nsdispatch is called and nsswitch.conf
is read or re-read).
= Make the nsdispatch(3) core thread-safe.
= New status code for nsdispatch(3) `NS_RETURN', currently used to
signal ERANGE-type issues.
= syslog(3) problems, don't warn/err/abort.
= Try harder to avoid namespace pollution.
= Implement some shims to assist in porting NSS modules written for
the GNU C Library nsswitch interface.
Sponsored by: DARPA, Network Associates Laboratories
they resemble one another, but POSIX.1e interfaces were not sufficiently
expressive to do what we needed.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
%f and sufficiently short %g specifiers where the precision was
explicitly zero, no '#' flag was specified, and the floating point
argument was > 0 and <= 0.5. While at it, add some comments to better
explain the relevant bits of code.
Noticed by: Christoph Kukulies <kuku@physik.rwth-aachen.de>
