- 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.
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.
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.
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.
Add _lwp_getspecific_by_lwp() to get lwp specific data from other lwp's.
Protected by #ifdef _LWP_API_PRIVATE.
Approved by: Jason Thorpe <thorpej@netbsd.org>
Instead, free an LWP's specificdata from lwp_exit() (if it is not the
last LWP) or exit1() (if it is the last LWP). For consistency, free the
proc's specificdata from exit1() as well. Add lwp_finispecific() and
proc_finispecific() functions to make this more convenient.
wrappers around the speicificdata subroutines. Also:
- Call the new lwpinit() function from main() after calling procinit().
- Move some pool initialization out of kern_proc.c and into files that
are directly related to the pools in question (kern_lwp.c and kern_ras.c).
- Convert uipc_sem.c to proc_{get,set}specific(), and eliminate the p_ksems
member from struct proc.
re-used by another cpu immediately. in that case, lwp_exit2() will
access freed memory. to fix this:
- remove curlwp from p_lwps in exit1() rather than letting lwp_exit2() do so.
- add assertions to ensure freed proc has no lwps.
kern/24329 from me and kern/24574 from Havard Eidnes.
the latter is not a appropriate place to do so and it broke vfork.
- deactivate pmap before calling cpu_exit() to keep a balance of
pmap_activate/deactivate.
process context ('reaper').
From within the exiting process context:
* deactivate pmap and free vmspace while we can still block
* introduce MD cpu_lwp_free() - this cleans all MD-specific context (such
as FPU state), and is the last potentially blocking operation;
all of cpu_wait(), and most of cpu_exit(), is now folded into cpu_lwp_free()
* process is now immediatelly marked as zombie and made available for pickup
by parent; the remaining last lwp continues the exit as fully detached
* MI (rather than MD) code bumps uvmexp.swtch, cpu_exit() is now same
for both 'process' and 'lwp' exit
uvm_lwp_exit() is modified to never block; the u-area memory is now
always just linked to the list of available u-areas. Introduce (blocking)
uvm_uarea_drain(), which is called to release the excessive u-area memory;
this is called by parent within wait4(), or by pagedaemon on memory shortage.
uvm_uarea_free() is now private function within uvm_glue.c.
MD process/lwp exit code now always calls lwp_exit2() immediatelly after
switching away from the exiting lwp.
g/c now unneeded routines and variables, including the reaper kernel thread
exec case, as the emulation already has the ability to intercept that
with the e_proc_exec hook. It is the responsability of the emulation to
take appropriaye action about lwp_emuldata in e_proc_exec.
Patch reviewed by Christos.
Remove p_raslock and rename p_lwplock p_lock (one lock is enough).
Simplify window test when adding a ras and correct test on VM_MAXUSER_ADDRESS.
Avoid unpredictable branch in i386 locore.S
(pad fields left in struct proc to avoid kernel bump)
