- Set a lower priority for AIO-worker thread, because current could cause
interactivity problems (eg. with qemu - thanks <xtraeme> for testing).
Mark it as XXX for now - after priority model change, this should
be reconsidered anyway.
- Do not copyout() with lock held in sys_aio_cancel().
- Fix a leak of the lock in aio_process().
- Check for any error of cv_wait_sig().
- Cache p->p_aio in aio_exit().
Thanks <ad> for catching the issues!
route_in6, struct route_iso), replacing all caches with a struct
route.
The principle benefit of this change is that all of the protocol
families can benefit from route cache-invalidation, which is
necessary for correct routing. Route-cache invalidation fixes an
ancient PR, kern/3508, at long last; it fixes various other PRs,
also.
Discussions with and ideas from Joerg Sonnenberger influenced this
work tremendously. Of course, all design oversights and bugs are
mine.
DETAILS
1 I added to each address family a pool of sockaddrs. I have
introduced routines for allocating, copying, and duplicating,
and freeing sockaddrs:
struct sockaddr *sockaddr_alloc(sa_family_t af, int flags);
struct sockaddr *sockaddr_copy(struct sockaddr *dst,
const struct sockaddr *src);
struct sockaddr *sockaddr_dup(const struct sockaddr *src, int flags);
void sockaddr_free(struct sockaddr *sa);
sockaddr_alloc() returns either a sockaddr from the pool belonging
to the specified family, or NULL if the pool is exhausted. The
returned sockaddr has the right size for that family; sa_family
and sa_len fields are initialized to the family and sockaddr
length---e.g., sa_family = AF_INET and sa_len = sizeof(struct
sockaddr_in). sockaddr_free() puts the given sockaddr back into
its family's pool.
sockaddr_dup() and sockaddr_copy() work analogously to strdup()
and strcpy(), respectively. sockaddr_copy() KASSERTs that the
family of the destination and source sockaddrs are alike.
The 'flags' argumet for sockaddr_alloc() and sockaddr_dup() is
passed directly to pool_get(9).
2 I added routines for initializing sockaddrs in each address
family, sockaddr_in_init(), sockaddr_in6_init(), sockaddr_iso_init(),
etc. They are fairly self-explanatory.
3 structs route_in6 and route_iso are no more. All protocol families
use struct route. I have changed the route cache, 'struct route',
so that it does not contain storage space for a sockaddr. Instead,
struct route points to a sockaddr coming from the pool the sockaddr
belongs to. I added a new method to struct route, rtcache_setdst(),
for setting the cache destination:
int rtcache_setdst(struct route *, const struct sockaddr *);
rtcache_setdst() returns 0 on success, or ENOMEM if no memory is
available to create the sockaddr storage.
It is now possible for rtcache_getdst() to return NULL if, say,
rtcache_setdst() failed. I check the return value for NULL
everywhere in the kernel.
4 Each routing domain (struct domain) has a list of live route
caches, dom_rtcache. rtflushall(sa_family_t af) looks up the
domain indicated by 'af', walks the domain's list of route caches
and invalidates each one.
- Add POSIX defined system variables and constants of AIO_LISTIO_MAX and
AIO_MAX values. Both with _POSIX_ASYNCHRONOUS_IO, provide them in
sysconf(3) and getconf(1) interfaces.
- Clean up sysconf(3) for handling sysctl nodes dynamically.
I think it existed to cache the numbers in kernel memory of a zombie when
proc->p_stats was part of the 'u' area - so got freed earlier and wouldn't
(easily) be accessible from a separate process. However since both the
p_ru and p_stats fields are freed at the same time it is no longer needed.
Ride the recent 4.99.19 version change.
Seems to be quite stable. Some work still left to do.
Please note, that syscalls are not yet MP-safe, because
of the file and vnode subsystems.
Reviewed by: <tech-kern>, <ad>
which can either be copied directly to userspace, or converted then copied.
Saves replicating a lot of code in the compat functions (esp. for
getvfsstat) at a cast of an extra function call in the non-emulated case -
which is unlikely to be measurable given the other costs of the actions
involved (even on vax).
Remove dofhstat() and dofhstatvfs() (and the last caller).
Remove some redundant stackgap_init() calls.
to the real root. Rather that do the check inside lookup() - where it
applies to to every ".." in a pathname, explicitly check the start of
the caller-supplied buffers and any absolute symbolic links.
Note that in the latter case the re-search from the real root is supressed.
Should fix PR kern/36225
emulation lookups.
If doing a lookup relative to the emulation root, prepend the emulation root
to the traced filename.
While here pass the filename length through to the ktrace code since namei()
knows the length and ktr_namei() would have to call strlen().
Note: that if namei() is being called during execve processing, the emulation
root name isn't available and "/emul/???" is used. Also namei() has to use
strlen() to get the lenght on the emulatoon root - even though it is a
compile-time constant string.
Since this is called in fork() it does rather need to give the child
process the parent's emulation root.
This means that (for example) an emulated shell will, by default, run
programs from the emulation root.
avoid having to allocate space in the 'stackgap'
- which is very LWP unfriendly.
The additional code for non-emulation namei() is trivial, the reduction for
the emulations is massive.
The vnode for a processes emulation root is saved in the cwdi structure
during process exec.
If the emulation root the TRYEMULROOT flag are set, namei() will do an initial
search for absolute pathnames in the emulation root, if that fails it will
retry from the normal root.
".." at the emulation root will always go to the real root, even in the middle
of paths and when expanding symlinks.
Absolute symlinks found using absolute paths in the emulation root will be
relative to the emulation root (so /usr/lib/xxx.so -> /lib/xxx.so links
inside the emulation root don't need changing).
If the root of the emulation would be returned (for an emulation lookup), then
the real root is returned instead (matching the behaviour of emul_lookup,
but being a cheap comparison here) so that programs that scan "../.."
looking for the root dircetory don't loop forever.
The target for symbolic links is no longer mangled (it used to get the
CHECK_ALT_xxx() treatment, so could get /emul/xxx prepended).
CHECK_ALT_xxx() are no more. Most of the change is deleting them, and adding
TRYEMULROOT to the flags to NDINIT().
A lot of the emulation system call stubs could now be deleted.
to skip unnecessary flushing when layered file system vnodes are recycled.
this also prevents a deadlock with the dodgy LFS putpages routine.
fixes the non-LFS part of PR 36150.
the "mountpoint" vnode twice due to an error branch.
thanks go to Gert Doering for reporting the problem and testing the fix
and to Juergen Hannken-Illjes for much of the analysis work leading to
the discovery of the problem cause
corresponding flags.
Revert softdep_trackbufs() to its state before vn_start_write() was added.
Remove from struct mount now unneeded flags IMNT_SUSPEND* and
members mnt_writeopcountupper, mnt_writeopcountlower and mnt_leaf.
Welcome to 4.99.17
Make sure that if we pull a buffer off of the read queue that it really
is a read request. Lower in this routine we base which queue we
dequeue the request from on its read/write state. Thus if a write
op ever ended up on the read queue, we'd explode (dereference NULL).
- 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.
yamt