combined. Also prepare for adding VP repossession later.
- kern_sa.c: sa_yield/sa_switch: detect if there are pending unblocked
upcalls.
- kern_sa.c: sa_unblock_userret/sa_setwoken: queue LWPs about to invoke
an unblocked upcall on the sa_wokenq. put queued LWPs in a state where
they can be put in the cache. notify LWP on the VP about pending
upcalls.
- kern_sa.c: sa_upcall_userret: check sa_wokenq for pending upcalls,
generate unblocked upcalls with multiple event sas
- kern_sa.c: sa_vp_repossess/sa_vp_donate: g/c, restore original
sa_vp_repossess
General idea: only consider the LWP on the VP for signal delivery, all
other LWPs are either asleep or running from waking up until repossessing
the VP.
- in kern_sig.c:kpsignal2: handle all states the LWP on the VP can be in
- in kern_sig.c:proc_stop: only try to stop the LWP on the VP. All other
LWPs will suspend in sa_vp_repossess() until the VP-LWP donates the VP.
Restore original behaviour (before SA-specific hacks were added) for
non-SA processes.
- in kern_sig.c:proc_unstop: only return the LWP on the VP
- handle sa_yield as case 0 in sa_switch instead of clearing L_SA, add an
L_SA_YIELD flag
- replace sa_idle by L_SA_IDLE flag since it was either NULL or == sa_vp
Also don't output itimerfire overrun warning if the process is already
exiting.
Also g/c sa_woken because it's not used.
Also g/c some #if 0 code.
we pass via sigctx, so that it guaranteed that the memory wouldn't be
paged out at the time the signal arrives
potential problem pointed out by YAMAMOTO Takashi
set using a pointer, to save couple bytes in struct sigctx
also fix fallout from recent lwp_wakeup() change, where we failed to properly
detect if tsleep() returned as result of lwp_wakeup() or signal outside
our wait set; could have caused problems for threaded apps using sigwait(2)
et.al.
file system.
The function vfs_write_suspend stops all new write operations to a file
system, allows any file system modifying system calls already in progress
to complete, then sync's the file system to disk and returns. The
function vfs_write_resume allows the suspended write operations to
complete.
From FreeBSD with slight modifications.
Approved by: Frank van der Linden <fvdl@netbsd.org>
Right now the only flag is used to indicate if a ksiginfo_t is a
result of a trap. Add a predicate macro to test for this flag.
* Add initialization macros for ksiginfo_t's.
* Add accssor macro for ksi_trap. Expands to 0 if the ksiginfo_t was
not the result of a trap. This matches the sigcontext trapcode semantics.
* In kpsendsig(), use KSI_TRAP_P() to select the lwp that gets the signal.
Inspired by Matthias Drochner's fix to kpsendsig(), but correctly handles
the case of non-trap-generated signals that have a > 0 si_code.
This patch fixes a signal delivery problem with threaded programs noted by
Matthias Drochner on tech-kern.
As discussed on tech-kern. Reviewed and OK's by Christos.
- add simple lock for the list
- make get function remove the item from the list
- eliminate superfluous functions
thanks to enami and matt for the feedback.
the information there.
TODO:
1. since timer stuff gets called from an interrupt context, we could
preallocate ksiginfo_t's from the pool, so we don't need a kmem
pool.
2. probably the sa signal delivery syscall can be changed to take
a ksiginfo_t so we can use only one pool.
3. maybe when we add realtime signal support, add a resource limit
on the number of ksiginfo_t's a process can allocate.
The patch below (hopefully) improves some signaling problems
found by Nathan.
It also contains some cleanup of the sa_upcall_userret() function
removing any sleep calls using PCATCH.
Unblocked threads now only use an upcall stack after they
acquire the virtual CPU.
This prevents unblocked threads from stealing all available
upcall stacks.
Tested by Nick Hudson.
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.
Bump the kernel rev up to 1.6V
be returning because the code path that calls is will very likely call
setrunnable() again on the returned thread, leading to a panic because
the thread returned is already at LSRUN. This fixes a problem where netbsd
would panic when using gdb (5.3) on a process with multiple lwp's like this:
% gdb program
(gdb) run
^C
(gdb) quit
sa_switch() invocations while exiting. Test P_SA instead of L_SA, out
of paranoia. Avoids a possible remrunqueue panic reported by Havard
Eidnes.
Release the kernel lock before calling the userret function to exit in
sigexit(). Problem noted by Paul Kranenburg.
timeout
the semantics of 'timeout' parameter differ to POSIX for the syscall
(not const, may be modified by kernel if interrupted from the wait) -
libc will provide appropriate wrapper
since sigwaitinfo(2) will be implemented as wrapper around sigtimedwait()
too, remove it's reserved slot and move sigqueue slot 'up', freeing
slot #246
* Change the semantics of proc_unstop() slightly, so that it is
responsible for making all stopped LWPs runnable, instead of
all-but-one. Return value is a LWP that can be interrupted if doing
so is necessary to take a signal. Adjust callers of proc_stop() to
the new, simpler semantics.
* When a non-continue signal is delivered to a stopped process and
there is a LWP sleeping interruptably, call setrunnable() (by way
of the 'out:' target in psignal1) instead of calling unsleep() so
that it becomes LSSTOP in issignal() and continuable by
proc_unstop(). Addresses PR kern/19990 by Martin Husemann, with
suggestions from enami tsugutomo.
