- cv_wait and friends: after resuming execution, check to see if we have
been restarted as a result of cv_signal. If we have, but cannot take
the wakeup (because of eg a pending Unix signal or timeout) then try to
ensure that another LWP sees it. This is necessary because there may
be multiple waiters, and at least one should take the wakeup if possible.
Prompted by a discussion with pooka@.
- typedef struct lwp lwp_t;
- int -> bool, struct lwp -> lwp_t in a few places.
- Better detect simple cycles of threads calling _lwp_wait and return
EDEADLK. Does not handle deeper cycles like t1 -> t2 -> t3 -> t1.
- If there are multiple threads in _lwp_wait, then make sure that
targeted waits take precedence over waits for any LWP to exit.
- When checking for deadlock, also count the number of zombies currently
in the process as potentially reapable. Whenever a zombie is murdered,
kick all waiters to make them check again for deadlock.
- Add more comments.
Also, while here:
- LOCK_ASSERT -> KASSERT in some places
- lwp_free: change boolean arguments to type 'bool'.
- proc_free: let lwp_free spin waiting for the last LWP to exit, there's
no reason to do it here.
- Don't bother sorting the sleep queues, since user space controls the
order of removal.
- Change setrunnable(t) to lwp_unsleep(t). No functional change from the
perspective of user applications.
- Minor cosmetic changes.
so it's not worth counting.
- lwp_wakeup: set LW_UNPARKED on the target. Ensures that _lwp_park will
always be awoken even if another system call eats the wakeup, e.g. as a
result of an intervening signal. To deal with this correctly for other
system calls will require a different approach.
- _lwp_unpark, _lwp_unpark_all: use setrunnable if the LWP is not parked
on the same sync queue: (1) simplifies the code a bit as there no point
doing anything special for this case (2) makes it possible for p_smutex
to be replaced by p_mutex and (3) restores the guarantee that the 'hint'
argument really is just a hint.
separate functions that don't do the copyout.
This allows all the compat_xxx versions to convert the 'struct stat' to
the correct format without using the 'stackgap'.
The stackgap isn't at all LWP friendly, and needs to be removed from
any compat functions that might involve threads (inc. clone()).
The code is still binary compatible with existing LKMs.
as possible. For that, split out a function which does the allocation
of a softc (without linking it into global structures) and a function
which inserts the device into the global alldevs lists and the per-driver
cd_devs.
There is a little semantic change involved: the pseudo-device code didn't
interpret FSTATE_STAR as such, for no good reason. This looks harmless;
I'll modify driver frontends as I find ways to test.
Get config_makeroom() out of the public namespace - that's clearly an
internal of autoconf which drivers can't be allowed to deal with.
length separately.
Use this for foreign-endianess labels in wedge autodiscovery, and
calculate the checksum of those before we swap various fields in the
label.
with newlock2 merge:
Replace the Mach-derived boolean_t type with the C99 bool type. A
future commit will replace use of TRUE and FALSE with true and false.
On i386 (at least) gcc manages two generate two forwards branches which are not
usually taken for the old code, and one forwards branch that is usually taken
for my 'improved version'. Since (IIRC) both athlon and P4 will predict
forwards branches 'not taken' the old code is likely to be faster :-(
Faster variants exist, especially ones using the cmov instruction.
option SYSCALL_STATS counts the number of times each system call is made
option SYSCALL_TIMES counts the amount of time spent in each system call
Currently the counting hooks have only been added to the i386 system call
handler, and the time spent in interrupts is not subtracted.
It ought also be possible to add the times to the processes profiling
counters in order to get a more accurate user/system/interrupt split.
The counts themselves are readable via the sysctl interface.
(depracted some time ago) 'struct kinfo_proc' returned by sysctl.
Move the definitions to sys/syctl.h and rename in order to ensure all the
users are located.
parentheses in return statements.
Cosmetic: don't open-code TAILQ_FOREACH().
Cosmetic: change types of variables to avoid oodles of casts: in
in6_src.c, avoid casts by changing several route_in6 pointers
to struct route pointers. Remove unnecessary casts to caddr_t
elsewhere.
Pave the way for eliminating address family-specific route caches:
soon, struct route will not embed a sockaddr, but it will hold
a reference to an external sockaddr, instead. We will set the
destination sockaddr using rtcache_setdst(). (I created a stub
for it, but it isn't used anywhere, yet.) rtcache_free() will
free the sockaddr. I have extracted from rtcache_free() a helper
subroutine, rtcache_clear(). rtcache_clear() will "forget" a
cached route, but it will not forget the destination by releasing
the sockaddr. I use rtcache_clear() instead of rtcache_free()
in rtcache_update(), because rtcache_update() is not supposed
to forget the destination.
Constify:
1 Introduce const accessor for route->ro_dst, rtcache_getdst().
2 Constify the 'dst' argument to ifnet->if_output(). This
led me to constify a lot of code called by output routines.
3 Constify the sockaddr argument to protosw->pr_ctlinput. This
led me to constify a lot of code called by ctlinput routines.
4 Introduce const macros for converting from a generic sockaddr
to family-specific sockaddrs, e.g., sockaddr_in: satocsin6,
satocsin, et cetera.
P_*/L_* naming convention, and rename the in-kernel flags to avoid
conflict. (P_ -> PK_, L_ -> LW_ ). Add back the (now unused) LSDEAD
constant.
Restores source compatibility with pre-newlock2 tools like ps or top.
Reviewed by Andrew Doran.
process was reparented. Change proc_free() to copy the rusage to a buffer
on the stack if required, so it can be passed both to the debugger and
to the real parent process.
Fixes kern/35582 (kernel panics with gdb).
