- In simple_lock_switchcheck(), allow/enforce exactly one lock to be
held: sched_lock.
- Per e-mail to tech-smp from Bill Sommerfeld, r/w spin locks have
an interlock at splsched(), rather than splhigh().
in the non-MULTIPROCESSOR case (LOCKDEBUG requires it). Scheduler
lock is held upon entry to mi_switch() and cpu_switch(), and
cpu_switch() releases the lock before returning.
Largely from Bill Sommerfeld, with some minor bug fixes and
machine-dependent code hacking from me.
- LOCK_ASSERT(), which expands to KASSERT() if LOCKDEBUG.
- new simple_lock_held(), which tests if the calling CPU holds
the specified simple lock.
From Bill Sommerfeld, modified slightly by me.
instead test for (p->p_flag & I_INMEM), and don't access the U-area
(via p->p_stats) if that bit is clear. Fixes the hangs people have
seen when the system is paging and the user runs top/ps/w.
simple locks are held by CPUs. Remove p_simple_locks (which was
unused anyway, really), and add a LOCKDEBUG check for held simple
locks in mi_switch(). Grow p_locks to an int to take up the space
previously used by p_simple_locks so that the proc structure doens't
change size.
NTP is not defined.
Also removes sysctl_ntptime, since that's unreferenced without NTP.
ntp_gettime(2) is left alone, since it doesn't raise SIGSYS, which sys_nosys()
does.
sig = (int)(long)*(caddr_t *)data;
to *properly* dereference the passed data. this makes signals on
ptys actually *work* on the sparc64 port. from mycroft.
XXX: the release branch version needs this ASAP as it is probably
unstable on ILP32BE.
int lf_advlock __P((struct lockf **,
off_t, caddr_t, int, struct flock *, int));
to
int lf_advlock __P((struct vop_advlock_args *, struct lockf **, off_t));
This matches common usage and is also compatible with similar change
in FreeBSD (though they use u_quad_t as last arg).
Move platform db_trap callback from arch/mips into ddb as suggested by
jhawk. This callback is used by platform code to manage things like
watchdogs that should be disabled while in ddb. Done as a callback
for processors such as mips that support lots of different systems.
vslock the user pages for the data being copied out to userspace,
so that we won't sleep while holding a lock in case we need to
fault the pages in.
- Sprinkle some const and ANSI'ify some things while here.
Stops sleeps from returning early (by up to a clock tick), and return 0
ticks for timeouts that should happen now or in the past.
Returning 0 is different from the legacy hzto() interface, and callers
need to check for it.
check that newstart + size - 1 doesn't overflow the end of the extent, rather
than the "dontcross" value, which can easily overflow the end of an extent
when being asked for an object with a large boundary requirement. this test
is more valid, in any case, and fixes extent_alloc() failure when the start of
the extent is not "aligned".
to machine memory size upon boot if the number has not been specified
explicitly in kernel config - at this moment, 0.5% of system
memory is used for vnodes (but minimum NVNODE vnodes)
use that to inform about way to raise current limit when we reach maximum
number of processes, descriptors or vnodes
XXX hopefully I catched all users of tablefull()
<vm/pglist.h> -> <uvm/uvm_pglist.h>
<vm/vm_inherit.h> -> <uvm/uvm_inherit.h>
<vm/vm_kern.h> -> into <uvm/uvm_extern.h>
<vm/vm_object.h> -> nothing
<vm/vm_pager.h> -> into <uvm/uvm_pager.h>
also includes a bunch of <vm/vm_page.h> include removals (due to redudancy
with <vm/vm.h>), and a scattering of other similar headers.
developed by Christopher G. Demetriou for the NetBSD Project.") with
a generic NetBSD one ("This product includes software developed for the
NetBSD Project. See http://www.netbsd.org/ for information about NetBSD.")
so that this same set of terms can be used by others if they so desire.
(Eventually i'll be converting more/all of my code.)
* Handle KERN_PROC_SESSION that has been defined in <sys/sysctl.h> from
day one.
* Add handlers for KERN_PROC_GID and KERN_PROC_RGID.
* If "op" doesn't valid, return EINVAL.
- document a data structure invariant in lockf.h
- add KASSERT() to check the invariant.
- be more consistent about dequeuing ourselves from the blocked list
after a tsleep().
- Fix two places where the invariant is violated.
- correct a few comments here and there
- If we're still following a lock dependancy chain after maxlockdepth
processes and haven't gotten back to the start, assume that we're in a
cycle anyway and return EDEADLK.
Fix is a superset of an existing fix in FreeBSD, but independantly
derived.
Fixes kern/3860.
- add a new global variable, doing_shutdown, which is nonzero if
vfs_shutdown() or panic() have been called.
- in panic, set RB_NOSYNC if doing_shutdown is already set on entry
so we don't reenter vfs_shutdown if we panic'ed there.
- in vfs_shutdown, don't use proc0's process for sys_sync unless
curproc is NULL.
- in lockmgr, attribute successful locks to proc0 if doing_shutdown
&& curproc==NULL, and panic if we can't get the lock right away; avoids the
spurious lockmgr DIAGNOSTIC panic from the ddb reboot command.
- in subr_pool, deal with curproc==NULL in the doing_shutdown case.
- in mfs_strategy, bitbucket writes if doing_shutdown, so we don't
wedge waiting for the mfs process.
- in ltsleep, treat ((curproc == NULL) && doing_shutdown) like the
panicstr case.
Appears to fix: kern/9239, kern/10187, kern/9367.
May also fix kern/10122.
interlock is released once the scheduler is locked, so that a race
between a sleeper and an awakener is prevented in a multiprocessor
environment. Provide a tsleep() macro that provides the old API.
on LP64 systems (and probably the SPARC) since the __cmsg_alignbytes()
changes went in.
- Change file descriptor passing to use CMSG_DATA(), not (cm + 1). This
pretty much has to be done in order to make it work properly on LP64,
and considering that it's been broken this long...
- Use CMSG_SPACE() to determine the mbuf length needed for a given
control message, and CMSG_LEN() to stash in the cmsg_len member.
"KERN_SYSVIPC_SEM_INFO" and "KERN_SYSVIPC_SHM_INFO" to return the
info and data structures for the relevent SysV IPC types. The return
structures use fixed-size types and should be compat32 safe. All
user-visible changes are protected with
#if !defined(_POSIX_C_SOURCE) && !defined(_XOPEN_SOURCE)
Make all variable declarations extern in msg.h, sem.h and shm.h and
add relevent variable declarations to sysv_*.c and remove unneeded
header files from those .c files.
Make compat14 SysV IPC conversion functions and sysctl_file() static.
Change the data pointer to "void *" in sysctl_clockrate(),
sysctl_ntptime(), sysctl_file() and sysctl_doeproc().
p_cpu member to struct proc. Use this in certain places when
accessing scheduler state, etc. For the single-processor case,
just initialize p_cpu in fork1() to avoid having to set it in the
low-level context switch code on platforms which will never have
multiprocessing.
While I'm here, comment a few places where there are known issues
for the SMP implementation.
- need deep compare of open files, not a shallow pointer compare.
- reorder fdrelease()/FILE_UNUSE() invocations so fdrelease doesn't
block waiting for something which can't happen until after it returns.
doing a cpu_set_kpc(), just pass the entry point and argument all
the way down the fork path starting with fork1(). In order to
avoid special-casing the normal fork in every cpu_fork(), MI code
passes down child_return() and the child process pointer explicitly.
This fixes a race condition on multiprocessor systems; a CPU could
grab the newly created processes (which has been placed on a run queue)
before cpu_set_kpc() would be performed.
sys_semconfig into a placebo system call, to avoid giving folks an
easy way to wedge processes which use semaphores.
NOTE: unlike 386bsd and freebsd, processes which did not have
semaphore undo records would not be affected by this problem (reducing
it from a serious local denial-of-service problem to a largely
cosmetic problem, since virtually nobody uses semaphores). But the
code is just Wrong so we're ripping it out anyway.
by Anders Magnusson.
Honor elem_count in the KERN_PROC2 case, as well as overall buffer
space. The only user-land code to use this set the elem_count to
"buffer_space / elem_size", so we've had no incorrect behaviour to date.
- Change ktrace interface to pass in the current process, rather than
p->p_tracep, since the various ktr* function need curproc anyway.
- Add curproc as a parameter to mi_switch() since all callers had it
handy anyway.
- Add a second proc argument for inferior() since callers all had
curproc handy.
Also, miscellaneous cleanups in ktrace:
- ktrace now always uses file-based, rather than vnode-based I/O
(simplifies, increases type safety); eliminate KTRFLAG_FD & KTRFAC_FD.
Do non-blocking I/O, and yield a finite number of times when receiving
EWOULDBLOCK before giving up.
- move code duplicated between sys_fktrace and sys_ktrace into ktrace_common.
- simplify interface to ktrwrite()
state into global and per-CPU scheduler state:
- Global state: sched_qs (run queues), sched_whichqs (bitmap
of non-empty run queues), sched_slpque (sleep queues).
NOTE: These may collectively move into a struct schedstate
at some point in the future.
- Per-CPU state, struct schedstate_percpu: spc_runtime
(time process on this CPU started running), spc_flags
(replaces struct proc's p_schedflags), and
spc_curpriority (usrpri of processes on this CPU).
- Every platform must now supply a struct cpu_info and
a curcpu() macro. Simplify existing cpu_info declarations
where appropriate.
- All references to per-CPU scheduler state now made through
curcpu(). NOTE: this will likely be adjusted in the future
after further changes to struct proc are made.
Tested on i386 and Alpha. Changes are mostly mechanical, but apologies
in advance if it doesn't compile on a particular platform.
sommerfeld