Instead of:
foo = malloc(sizeof(foo), M_WAIT);
bzero(foo, sizeof(foo));
You can now (and please do) use:
foo = malloc(sizeof(foo), M_WAIT | M_ZERO);
In the future this will enable us to do idle-time pre-zeroing of
malloc-space.
reducues the maintenance load for the mutex code. The only MD portions
of the mutex code are in machine/mutex.h now, which include the assembly
macros for handling mutexes as well as optionally overriding the mutex
micro-operations. For example, we use optimized micro-ops on the x86
platform #ifndef I386_CPU.
- Change the behavior of the SMP_DEBUG kernel option. In the new code,
mtx_assert() only depends on INVARIANTS, allowing other kernel developers
to have working mutex assertiions without having to include all of the
mutex debugging code. The SMP_DEBUG kernel option has been renamed to
MUTEX_DEBUG and now just controls extra mutex debugging code.
- Abolish the ugly mtx_f hack. Instead, we dynamically allocate
seperate mtx_debug structures on the fly in mtx_init, except for mutexes
that are initiated very early in the boot process. These mutexes
are declared using a special MUTEX_DECLARE() macro, and use a new
flag MTX_COLD when calling mtx_init. This is still somewhat hackish,
but it is less evil than the mtx_f filler struct, and the mtx struct is
now the same size with and without mutex debugging code.
- Add some micro-micro-operation macros for doing the actual atomic
operations on the mutex mtx_lock field to make it easier for other archs
to override/optimize mutex ops if needed. These new tiny ops also clean
up the code in some places by replacing long atomic operation function
calls that spanned 2-3 lines with a short 1-line macro call.
- Don't call mi_switch() from mtx_enter_hard() when we block while trying
to obtain a sleep mutex. Calling mi_switch() would bogusly release
Giant before switching to the next process. Instead, inline most of the
code from mi_switch() in the mtx_enter_hard() function. Note that when
we finally kill Giant we can back this out and go back to calling
mi_switch().
"administrative" authorization checks. In most cases, the VADMIN test
checks to make sure the credential effective uid is the same as the file
owner.
o Modify vaccess() to set VADMIN as an available right if the uid is
appropriate.
o Modify references to uid-based access control operations such that they
now always invoke VOP_ACCESS() instead of using hard-coded policy checks.
o This allows alternative UFS policies to be implemented by replacing only
ufs_access() (such as mandatory system policies).
o VOP_ACCESS() requires the caller to hold an exclusive vnode lock on the
vnode: I believe that new invocations of VOP_ACCESS() are always called
with the lock held.
o Some direct checks of the uid remain, largely associated with the QUOTA
and SUIDDIR code.
Reviewed by: eivind
Obtained from: TrustedBSD Project
implementation.
Add bus_generic_rl_{get,set,delete,release,alloc}_resource() functions
which provide generic operations for devices using resource list style
resource management.
This should simplify a number of bus drivers. Further commits to follow.
This was implemented by Shigeru YAMAMOTO-san and Jonathan Chen. I've
cleaned them up somewhat and they seem to work well enough to boot
current (but given current's state it can be hard to tell). Doug
Rabson also reviewed the design and signed off on it.
number of ext_buf counters that are possibly allocatable.
Do this because:
(i) It will make it easier to influence EXT_COUNTERS for if_sk,
if_ti (or similar) users where the driver allocates its own
ext_bufs and where it is important for the mbuf system to take
it into account when reserving necessary space for counters.
(ii) Facilitate some percentile calculation for netstat(1)
u_int64_t flag field, bounding the number of capabilities at 64,
but substantially cleaning up capability logic (there are currently
43 defined capabilities).
o Heads up to anyone actually using capabilities: the constant
assignments for various capabilities have been redone, so any
persistent binary capability stores (i.e., '$posix1e.cap' EA
backing files) must be recreated. If you have one of these,
you'll know about it, so if you have no idea what this means,
don't worry.
o Update libposix1e to reflect this new definition, fixing the
exposed functions that directly manipulate the flags fields.
Obtained from: TrustedBSD Project
and initialized during boot. This avoids bloating sizeof(struct lock).
As a side effect, it is no longer necessary to enforce the assumtion that
lockinit()/lockdestroy() calls are paired, so the LK_VALID flag has been
removed.
Idea taken from: BSD/OS.
a breakpoint in the kernel didn't use the proper argument list. To avoid
having to include the userland link.h header everyhwere that sys/linker.h
is used, make r_debug_state() a static function in link_elf.c as well.
return through doreti to handle ast's. This is necessary for the
clock interrupts to work properly.
- Change the clock interrupts on the x86 to be fast instead of threaded.
This is needed because both hardclock() and statclock() need to run in
the context of the current process, not in a separate thread context.
- Kill the prevproc hack as it is no longer needed.
- We really need Giant when we call psignal(), but we don't want to block
during the clock interrupt. Instead, use two p_flag's in the proc struct
to mark the current process as having a pending SIGVTALRM or a SIGPROF
and let them be delivered during ast() when hardclock() has finished
running.
- Remove CLKF_BASEPRI, which was #ifdef'd out on the x86 anyways. It was
broken on the x86 if it was turned on since cpl is gone. It's only use
was to bogusly run softclock() directly during hardclock() rather than
scheduling an SWI.
- Remove the COM_LOCK simplelock and replace it with a clock_lock spin
mutex. Since the spin mutex already handles disabling/restoring
interrupts appropriately, this also lets us axe all the *_intr() fu.
- Back out the hacks in the APIC_IO x86 cpu_initclocks() code to use
temporary fast interrupts for the APIC trial.
- Add two new process flags P_ALRMPEND and P_PROFPEND to mark the pending
signals in hardclock() that are to be delivered in ast().
Submitted by: jakeb (making statclock safe in a fast interrupt)
Submitted by: cp (concept of delaying signals until ast())
- Make softinterrupts (SWI's) almost completely MI, and divorce them
completely from the x86 hardware interrupt code.
- The ihandlers array is now gone. Instead, there is a MI shandlers array
that just contains SWI handlers.
- Most of the former machine/ipl.h files have moved to a new sys/ipl.h.
- Stub out all the spl*() functions on all architectures.
Submitted by: dfr
Add lockdestroy() and appropriate invocations, which corresponds to
lockinit() and must be called to clean up after a lockmgr lock is no
longer needed.
to accomodate the changes.
Here's a list of things that have changed (I may have left out a few); for a
relatively complete list, see http://people.freebsd.org/~bmilekic/mtx_journal
* Remove old (once useful) mcluster code for MCLBYTES > PAGE_SIZE which
nobody uses anymore. It was great while it lasted, but now we're moving
onto bigger and better things (Approved by: wollman).
* Practically re-wrote the allocation macros in sys/sys/mbuf.h to accomodate
new allocations which grab the necessary lock.
* Make sure that necessary mbstat variables are manipulated with
corresponding atomic() routines.
* Changed the "wait" routines, cleaned it up, made one routine that does
the job.
* Generalized MWAKEUP() macro. Got rid of m_retry and m_retryhdr, as they
are now included in the generalized "wait" routines.
* Sleep routines now use msleep().
* Free lists have locks.
* etc... probably other stuff I'm missing...
Things to look out for and work on later:
* find a better way to (dynamically) adjust EXT_COUNTERS
* move necessity to recurse on a lock from drain routines by providing
lock-free lower-level version of MFREE() (and possibly m_free()?).
* checkout include of mutex.h in sys/sys/mbuf.h - probably violating
general philosophy here.
The code has been reviewed quite a bit, but problems may arise... please,
don't panic! Send me Emails: bmilekic@freebsd.org
Reviewed by: jlemon, cp, alfred, others?
performed twice. Eliminate initialization that is already performed
by _aio_aqueue.
aio_physwakeup: Eliminate redundant synchronization that is already
performed by bufdone.
separately (nfs, cd9660 etc) or keept as a first element of structure
referenced by v_data pointer(ffs). Such organization leads to known problems
with stacked filesystems.
From this point vop_no*lock*() functions maintain only interlock lock.
vop_std*lock*() functions maintain built-in v_lock structure using lockmgr().
vop_sharedlock() is compatible with vop_stdunlock(), but maintains a shared
lock on vnode.
If filesystem wishes to export lockmgr compatible lock, it can put an address
of this lock to v_vnlock field. This indicates that the upper filesystem
can take advantage of it and use single lock structure for entire (or part)
of stack of vnodes. This field shouldn't be examined or modified by VFS code
except for initialization purposes.
Reviewed in general by: mckusick
