patch from a year ago: give file flags their own type. This does not
(yet) change the type used by system calls or library functions.
The underlying type was chosen to match what is returned by stat().
slower, and may be impeding adoption of -CURRENT by developers. We
recommend turning on WITNESS by default on crash boxes, and when doing
locking development. It will probably get turned on by default for a week
or two following any major locking commits, also.
Approved by: all and sundry (jhb, phk, ...)
this is a low-functionality change that changes the kernel to access the main
thread of a process via the linked list of threads rather than
assuming that it is embedded in the process. It IS still embeded there
but remove all teh code that assumes that in preparation for the next commit
which will actually move it out.
Reviewed by: peter@freebsd.org, gallatin@cs.duke.edu, benno rice,
- Create a private list of active pmaps rather than abusing the list of all
processes when we need to look up pmaps. The process list needs a sx lock
and we can't be getting sx locks in the middle of cpu_switch()
(pmap_activate() can call pmap_get_asn() from cpu_switch()). Instead, we
protect the list with a spinlock. This also means the list is shorter
since a pmap can be used by more than one process and we could (at least
in thoery) dink with pmap's more than once, but now we only touch each
pmap once when we have to update all of them.
- Wrap pmap_activate()'s code to get a new ASN in an explicit critical section
so that when it is called while doing an exec() we can't get preempted.
- Replace splhigh() in pmap_growkernel() with a critical section to prevent
preemption while we are adjusting the kernel page tables.
- Fixes abuse of PCPU_GET(), which doesn't return an L-value.
- Also adds some slight cleanups to the ASN handling by adding some macros
instead of magic numbers in relation to the ASN and ASN generations.
Reviewed by: dfr
some arches and the syscall table is machine-independent. It was
(bogusly) conditional on COMPAT_43, so this usually makes no difference.
ia64: in addition:
- replace the bogus cloned comment before osigreturn() by a correct one.
osigreturn() is just a stub fo ia64's.
- fix the formatting of cloned comment before sigreturn().
- fix the return code. use nosys() instead of returning ENOSYS to get
the same semantics as if the syscall is not in the syscall table.
Generating SIGSYS is actually correct here.
- fix style bugs.
powerpc: copy the cleaned up ia64 stub. This mainly fixes a bogus comment.
sparc64: copy the cleaned up the ia64 stub, since there was no stub before.
getpid, getuid, getgid and pipe, since they bootstrapped from
OSF/1 and never cleaned up. Switch to the native syscalls
on alpha so that the above functions work
MFC after: 7 days
and the reference to db_regs is *extern* from alpha/include/db_machdep.h
(put it in alpha/alpha/machdep.c)- this avoids the problems we've had
about different 'common' sizes prohibiting the kernel from linking.
NULL rather than curproc. Without this, if we trap early before
curthread is set, we recursively panic.
- In an SMP kernel, if we trap before curthread is set, then trap is going
to recursively panic trying to bump td->td_md.md_kernnest. The trap is
fatal anyways, so to make debugging easier just call printtrap() to
dump the trap info to the console and then halt.
Seigo Tanimura (tanimura) posted the initial delta.
I've polished it quite a bit reducing the need for locking and
adapting it for KSE.
Locks:
1 mutex in each filedesc
protects all the fields.
protects "struct file" initialization, while a struct file
is being changed from &badfileops -> &pipeops or something
the filedesc should be locked.
1 mutex in each struct file
protects the refcount fields.
doesn't protect anything else.
the flags used for garbage collection have been moved to
f_gcflag which was the FILLER short, this doesn't need
locking because the garbage collection is a single threaded
container.
could likely be made to use a pool mutex.
1 sx lock for the global filelist.
struct file * fhold(struct file *fp);
/* increments reference count on a file */
struct file * fhold_locked(struct file *fp);
/* like fhold but expects file to locked */
struct file * ffind_hold(struct thread *, int fd);
/* finds the struct file in thread, adds one reference and
returns it unlocked */
struct file * ffind_lock(struct thread *, int fd);
/* ffind_hold, but returns file locked */
I still have to smp-safe the fget cruft, I'll get to that asap.
and to inherently verify its validity. Alpha signal frames and trap
frames are different; this field identifies which format the context
is
Set the machine context format (signal frame) before copying it out
when sending a signal.
Approved by: -arch
mutex releases to not require flags for the cases when preemption is
not allowed:
The purpose of the MTX_NOSWITCH and SWI_NOSWITCH flags is to prevent
switching to a higher priority thread on mutex releease and swi schedule,
respectively when that switch is not safe. Now that the critical section
API maintains a per-thread nesting count, the kernel can easily check
whether or not it should switch without relying on flags from the
programmer. This fixes a few bugs in that all current callers of
swi_sched() used SWI_NOSWITCH, when in fact, only the ones called from
fast interrupt handlers and the swi_sched of softclock needed this flag.
Note that to ensure that swi_sched()'s in clock and fast interrupt
handlers do not switch, these handlers have to be explicitly wrapped
in critical_enter/exit pairs. Presently, just wrapping the handlers is
sufficient, but in the future with the fully preemptive kernel, the
interrupt must be EOI'd before critical_exit() is called. (critical_exit()
can switch due to a deferred preemption in a fully preemptive kernel.)
I've tested the changes to the interrupt code on i386 and alpha. I have
not tested ia64, but the interrupt code is almost identical to the alpha
code, so I expect it will work fine. PowerPC and ARM do not yet have
interrupt code in the tree so they shouldn't be broken. Sparc64 is
broken, but that's been ok'd by jake and tmm who will be fixing the
interrupt code for sparc64 shortly.
Reviewed by: peter
Tested on: i386, alpha
and it's associated state variables: icu_lock with the name "icu". This
renames the imen_mtx for x86 SMP, but also uses the lock to protect
access to the 8259 PIC on x86 UP. This also adds an appropriate lock to
the various Alpha chipsets which fixes problems with Alpha SMP machines
dropping interrupts with an SMP kernel.
- The MD functions critical_enter/exit are renamed to start with a cpu_
prefix.
- MI wrapper functions critical_enter/exit maintain a per-thread nesting
count and a per-thread critical section saved state set when entering
a critical section while at nesting level 0 and restored when exiting
to nesting level 0. This moves the saved state out of spin mutexes so
that interlocking spin mutexes works properly.
- Most low-level MD code that used critical_enter/exit now use
cpu_critical_enter/exit. MI code such as device drivers and spin
mutexes use the MI wrappers. Note that since the MI wrappers store
the state in the current thread, they do not have any return values or
arguments.
- mtx_intr_enable() is replaced with a constant CRITICAL_FORK which is
assigned to curthread->td_savecrit during fork_exit().
Tested on: i386, alpha
- Axe inlvtlb_ok as it was completely redundant with smp_active.
- Remove references to non-existent variable and non-existent file
in i386/include/smp.h.
- Don't perform initializations local to each CPU while holding the
ap boot lock on i386 while an AP bootstraps itself.
- Reorganize the AP startup code some to unify the latter half of the
functions to bring an AP up. Eventually this might be broken out into
a MI function in subr_smp.c.
- The MI portions of struct globaldata have been consolidated into a MI
struct pcpu. The MD per-CPU data are specified via a macro defined in
machine/pcpu.h. A macro was chosen over a struct mdpcpu so that the
interface would be cleaner (PCPU_GET(my_md_field) vs.
PCPU_GET(md.md_my_md_field)).
- All references to globaldata are changed to pcpu instead. In a UP kernel,
this data was stored as global variables which is where the original name
came from. In an SMP world this data is per-CPU and ideally private to each
CPU outside of the context of debuggers. This also included combining
machine/globaldata.h and machine/globals.h into machine/pcpu.h.
- The pointer to the thread using the FPU on i386 was renamed from
npxthread to fpcurthread to be identical with other architectures.
- Make the show pcpu ddb command MI with a MD callout to display MD
fields.
- The globaldata_register() function was renamed to pcpu_init() and now
init's MI fields of a struct pcpu in addition to registering it with
the internal array and list.
- A pcpu_destroy() function was added to remove a struct pcpu from the
internal array and list.
Tested on: alpha, i386
Reviewed by: peter, jake
o Hide nonstandard functions and types in <netinet/in.h> when
_POSIX_SOURCE is defined.
o Add some missing types (required by POSIX.1-200x) to <netinet/in.h>.
o Restore vendor ID from Rev 1.1 in <netinet/in.h> and make use of new
__FBSDID() macro.
o Fix some miscellaneous issues in <arpa/inet.h>.
o Correct final argument for the inet_ntop() function (POSIX.1-200x).
o Get rid of the namespace pollution from <sys/types.h> in
<arpa/inet.h>.
Reviewed by: fenner
Partially submitted by: bde
