do_sendfile(). This allows us to rearrange an if statement in order to
avoid doing an unnecesary call to vm_page_lock_queues(), and an attempt
at re-wiring the pages (which were wired in the vm_page_alloc() call).
Reviewed by: alc, jhb
open() of fhopen(). Currently this has no actual affect due to the
treatment of VAPPEND in vaccess() and vaccess_acl() as a subset of
VWRITE, but when MAC comes in, MAC will distinguish the two. Note:
if any file systems are cutting their own permission models, they
may wish to now take this into account.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
handler in the kernel at the same time. Also, allow for the
exec_new_vmspace() code to build a different sized vmspace depending on
the executable environment. This is a big help for execing i386 binaries
on ia64. The ELF exec code grows the ability to map partial pages when
there is a page size difference, eg: emulating 4K pages on 8K or 16K
hardware pages.
Flesh out the i386 emulation support for ia64. At this point, the only
binary that I know of that fails is cvsup, because the cvsup runtime
tries to execute code in pages not marked executable.
Obtained from: dfr (mostly, many tweaks from me).
- Sanity check the mount options list (remove duplicates) with
vfs_sanitizeopts().
- Fix some malloc(0)/free(NULL) bugs.
Reviewed by: rwatson (some time ago)
As this code is not actually used by any of the existing
interfaces, it seems unlikely to break anything (famous
last words).
The internal kernel interface to manipulate these attributes
is invoked using two new IO_ flags: IO_NORMAL and IO_EXT.
These flags may be specified in the ioflags word of VOP_READ,
VOP_WRITE, and VOP_TRUNCATE. Specifying IO_NORMAL means that
you want to do I/O to the normal data part of the file and
IO_EXT means that you want to do I/O to the extended attributes
part of the file. IO_NORMAL and IO_EXT are mutually exclusive
for VOP_READ and VOP_WRITE, but may be specified individually
or together in the case of VOP_TRUNCATE. For example, when
removing a file, VOP_TRUNCATE is called with both IO_NORMAL
and IO_EXT set. For backward compatibility, if neither IO_NORMAL
nor IO_EXT is set, then IO_NORMAL is assumed.
Note that the BA_ and IO_ flags have been `merged' so that they
may both be used in the same flags word. This merger is possible
by assigning the IO_ flags to the low sixteen bits and the BA_
flags the high sixteen bits. This works because the high sixteen
bits of the IO_ word is reserved for read-ahead and help with
write clustering so will never be used for flags. This merge
lets us get away from code of the form:
if (ioflags & IO_SYNC)
flags |= BA_SYNC;
For the future, I have considered adding a new field to the
vattr structure, va_extsize. This addition could then be
exported through the stat structure to allow applications to
find out the size of the extended attribute storage and also
would provide a more standard interface for truncating them
(via VOP_SETATTR rather than VOP_TRUNCATE).
I am also contemplating adding a pathconf parameter (for
concreteness, lets call it _PC_MAX_EXTSIZE) which would
let an application determine the maximum size of the extended
atribute storage.
Sponsored by: DARPA & NAI Labs.
so it needs an explicit #include <machine/frame.h> to get 'struct
trapframe'. The fact that it needs this at this level is rather bogus
but it will not compile without it.
the filelist_lock and check nfiles. This closes a race where we had to
unlock the filedesc to re-lock the filelist_lock.
Reported by: David Xu
Reviewed by: bde (mostly)
after a panic which is not an interrupt thread, or the thread which
caused the panic. Also, remove panicstr checks from msleep() and from
cv_wait() in order to allow threads to go to sleep and yeild the cpu
to the panicing thread, or to an interrupt thread which might
be doing the crashdump.
Reviewed by: jhb (and it was mostly his idea too)
support creation times such as UFS2) to the value of the
modification time if the value of the modification time is older
than the current creation time. See utimes(2) for further details.
Sponsored by: DARPA & NAI Labs.
semicolons from the end of macros:
#define FOO() bar(a,b,c);
becomes
#define FOO() bar(a,b,c)
Thus requiring the semicolon in the invocation of FOO. This is much
cleaner syntax and more consistent with expectations when writing
function-like things in source.
With both peril-sensitive sunglasses and flame-proof undies on, tighten
up some types, and work around some warnings generated by this. There
are some _horrible_ const/non-const issues in this code.
and a cluster in one shot.
o Introduce MBP_PERSIST and MBP_PERSISTENT control bits to mb_alloc();
MBP_PERSIST means "if you can allocate, then keep the cache lock
held on exit," and MBP_PERSISTENT means "a cache lock is alredy held
on entry, so allocate from the specified (already locked) cache."
They may be used in combination.
o m_getcl() uses the MBP_PERSIST/MBP_PERSISTENT interface so that it
doesn't drop the cache lock in between the mbuf and cluster allocations.
o m_getm(), which takes a size and allocates an mbuf + cluster "best fit"
chain, has been moved from uipc_mbuf.c to subr_mbuf.c and shown how to
use MBP_PERSIST/MBP_PERSISTENT to attempt to do a grouped allocation
without dropping the cache lock in between.
Why this is good: much less bus-locked lock acquires/drops when they're
not needed. Also, prototype for m_getcl():
struct mbuf * m_getcl(int how, short type, int flags);
"how" and "type" are self-explanatory. "flags" may be M_PKTHDR, in
which case m_getcl() will make the mbuf a pkthdr-mbuf.
While I'm in subr_mbuf.c:
o Every exported routine now has a nice comment with a description of
the expected arguments. Eventually, mbuf(9) needs to be re-vamped
but there's still more code to write/finalize before I get to that.
o internal macros have been changed a bit.
o consistently use 'short' for "type." This somehow slipped through
before (that 'type' was sometimes declared as int).
Alfred has been pushing for the MBP_PERSIST{,ENT} thing for almost a
year now. Luigi asked for m_getcl(), and will probably MFC that
part of this commit.
TODO [Related]: teach mb_free() about MBP_PERSIST{, ENT}.
1/ don't need to set td_state to TDS_RUNNING in fork_return.
it's already set in choosethread().
2/ Set a child process state to "normal" as opposed to "new"
when we allow it to be put on the run queue.
Allows child to receive signals from the parent if the parent
runs first and tries to immediatly signal he child.
Submitted by: (part 2) Thomas Moestl <tmoestl@gmx.net>
formulated. The correct states should be:
IDLE: On the idle KSE list for that KSEG
RUNQ: Linked onto the system run queue.
THREAD: Attached to a thread and slaved to whatever state the thread is in.
This means that most places where we were adjusting kse state can go away
as it is just moving around because the thread is..
The only places we need to adjust the KSE state is in transition to and from
the idle and run queues.
Reviewed by: jhb@freebsd.org
filedesc is already locked rather than having chroot() unlock the
filedesc so chroot_refuse_vdir_fds() can immediately relock it.
- Reorder chroot() a bitso that we do the namei lookup before checking
the process's struct filedesc. This closes at least one potential race
and allows us to only acquire the filedsec lock once in chroot().
- Push down Giant slightly into chroot().
page-zeroing code as well as from the general page-zeroing code and use a
lazy tlb page invalidation scheme based on a callback made at the end
of mi_switch.
A number of people came up with this idea at the same time so credit
belongs to Peter, John, and Jake as well.
Two-way SMP buildworld -j 5 tests (second run, after stabilization)
2282.76 real 2515.17 user 704.22 sys before peter's IPI commit
2266.69 real 2467.50 user 633.77 sys after peter's commit
2232.80 real 2468.99 user 615.89 sys after this commit
Reviewed by: peter, jhb
Approved by: peter
choosethread() in MI C code instead of doing it in in assembly in all the
various cpu_switch() functions. This fixes problems on ia64 and sparc64.
Reviewed by: julian, peter, benno
Tested on: i386, alpha, sparc64
- It actually works this time, honest!
- Fine grained TLB shootdowns for SMP on i386. IPI's are very expensive,
so try and optimize things where possible.
- Introduce ranged shootdowns that can be done as a single IPI.
- PG_G support for i386
- Specific-cpu targeted shootdowns. For example, there is no sense in
globally purging the TLB cache for where we are stealing a page from
the local unshared process on the local cpu. Use pm_active to track
this.
- Add some instrumentation for the tlb shootdown code.
- Rip out SMP code from <machine/cpufunc.h>
- Try and fix some very bogus PG_G and PG_PS interactions that were bad
enough to cause vm86 bios calls to break. vm86 depended on our existing
bugs and this was the cause of the VESA panics last time.
- Fix the silly one-line error that caused the 'panic: bad pte' last time.
- Fix a couple of other silly one-line errors that should have caused more
pain than they did.
Some more work is needed:
- pmap_{zero,copy}_page[_idle]. These can be done without IPI's if we
have a hook in cpu_switch.
- The IPI handlers need some cleanup. I have a bogus %ds load that can
be avoided.
- APTD handling is rather bogus and appears to be a large source of
global TLB IPI shootdowns for no really good reason.
I see speedups of between 1.5% and ~4% on buildworlds in a while 1 loop.
I expect to see a bigger difference when there is significant pageout
activity or the system otherwise has memory shortages.
I have backed out a few optimizations that I had been using over the last
few days in order to be a little more conservative. I'll revisit these
again over the next few days as the dust settles.
New option: DISABLE_PG_G - In case I missed something.
This allows accton(1) to be used with an append-only file.
PR: 7169
Reported by: Joao Carlos Mendes Luis <jonny@jonny.eng.br>
Reviewed by: bde
Approved by: sheldonh (mentor)
MFC after: 2 weeks
methodology similar to the vm_map_entry splay and the VM splay that Alan
Cox is working on. Extensive testing has appeared to have shown no
increase in overhead.
Disadvantages
Dirties more cache lines during lookups.
Not as fast as a hash table lookup (but still N log N and optimal
when there is locality of reference).
Advantages
vnode->v_dirtyblkhd is now perfectly sorted, making fsync/sync/filesystem
syncer operate more efficiently.
I get to rip out all the old hacks (some of which were mine) that tried
to keep the v_dirtyblkhd tailq sorted.
The per-vnode splay tree should be easier to lock / SMPng pushdown on
vnodes will be easier.
This commit along with another that Alan is working on for the VM page
global hash table will allow me to implement ranged fsync(), optimize
server-side nfs commit rpcs, and implement partial syncs by the
filesystem syncer (aka filesystem syncer would detect that someone is
trying to get the vnode lock, remembers its place, and skip to the
next vnode).
Note that the buffer cache splay is somewhat more complex then other splays
due to special handling of background bitmap writes (multiple buffers with
the same lblkno in the same vnode), and B_INVAL discontinuities between the
old hash table and the existence of the buffer on the v_cleanblkhd list.
Suggested by: alc
of being correct. None of the root mountable filesystems
do something at VFS_START().
Shorten a comment to fix a style bug while I'm here.
PR: kern/18505
pmap_swapin_proc/pmap_swapout_proc functions from the MD pmap code
and use a single equivalent MI version. There are other cleanups
needed still.
While here, use the UMA zone hooks to keep a cache of preinitialized
proc structures handy, just like the thread system does. This eliminates
one dependency on 'struct proc' being persistent even after being freed.
There are some comments about things that can be factored out into
ctor/dtor functions if it is worth it. For now they are mostly just
doing statistics to get a feel of how it is working.
Tell vop_strategy_pre() to use this instead.
- Ignore B_CLUSTER bufs. Their components are locked but they don't really
exist so they don't have to be. This isn't ideal but it is safe.
- Cache a pointer to the vnode's object in the buf.
- Hold a reference to that object in addition to the vnode's reference just
to be consistent.
- Cleanup code that got the object indirectly through the vp and VOP calls.
This fixes at least one case where we were calling GETVOBJECT without a lock.
It also avoids an expensive layered call at the cost of another pointer in
struct buf.
- Grab the vnode object early in exec when we still have the vnode lock.
- Cache the object in the image_params.
- Make use of the cached object in imgact_*.c
- Switch to the new vop_strategy_pre for lock validation.
VOP_STRATEGY requires only that the buf is locked UNLESS the block numbers need
to be translated. There may be other reasons, but as long as the underlying
layer uses a VOP to perform the operations they will be caught later.
- Disable original vop_strategy lock specification.
- Switch to the new vop_strategy_pre for lock validation.
VOP_STRATEGY requires only that the buf is locked UNLESS the block numbers need
to be translated. There may be other reasons, but as long as the underlying
layer uses a VOP to perform the operations they will be caught later.
queue lock (revision 1.33 of vm/vm_page.c removed them).
o Make the free queue lock a spin lock because it's sometimes acquired
inside of a critical section.
The file vfs_conf.c which was dealing with root mounting has
been repo-copied into vfs_mount.c to preserve history.
This makes nmount related development easier, and help reducing
the size of vfs_syscalls.c, which is still an enormous file.
Reviewed by: rwatson
Repo-copy by: peter
direct calls for the two places where the kernel calls into soft
updates code. Set up the hooks in softdep_initialize() and NULL
them out in softdep_uninitialize(). This change allows soft updates
to function correctly when ufs is loaded as a module.
Reviewed by: mckusick
close up the continued line after removing the cast made the line.
space before parentheses in indirect function call.
Add an addtional error handler case for the results of callback.
Submitted by: bde
The ability to schedule multiple threads per process
(one one cpu) by making ALL system calls optionally asynchronous.
to come: ia64 and power-pc patches, patches for gdb, test program (in tools)
Reviewed by: Almost everyone who counts
(at various times, peter, jhb, matt, alfred, mini, bernd,
and a cast of thousands)
NOTE: this is still Beta code, and contains lots of debugging stuff.
expect slight instability in signals..
- Add vfs_badlock_print to control whether or not we print lock violations
- Add vfs_badlock_panic to control whether we panic on lock violations
Both default to on to mimic the original behavior if DEBUG_VFS_LOCKS is on.
vnode in the case that the target exists and is the same vnode as
the parent (i.e. "mkdir ."). The namei() call does not leave the
vnode locked in this case even though you might expect it to.
This bug was mostly harmless in practice because unlocking an already
unlocked vnode currently does not trigger any panics or warnings.
Reviewed by: jeff
passed down the VFS stack. While I'm here, replace a '0' with a 'NULL'
to make the code more readable.
Sponsored by: DARPA, NAI Labs
Obtained from: TrustedBSD Project
MAKEDEV: Add MAKEDEV glue for the ti(4) device nodes.
ti.4: Update the ti(4) man page to include information on the
TI_JUMBO_HDRSPLIT and TI_PRIVATE_JUMBOS kernel options,
and also include information about the new character
device interface and the associated ioctls.
man9/Makefile: Add jumbo.9 and zero_copy.9 man pages and associated
links.
jumbo.9: New man page describing the jumbo buffer allocator
interface and operation.
zero_copy.9: New man page describing the general characteristics of
the zero copy send and receive code, and what an
application author should do to take advantage of the
zero copy functionality.
NOTES: Add entries for ZERO_COPY_SOCKETS, TI_PRIVATE_JUMBOS,
TI_JUMBO_HDRSPLIT, MSIZE, and MCLSHIFT.
conf/files: Add uipc_jumbo.c and uipc_cow.c.
conf/options: Add the 5 options mentioned above.
kern_subr.c: Receive side zero copy implementation. This takes
"disposable" pages attached to an mbuf, gives them to
a user process, and then recycles the user's page.
This is only active when ZERO_COPY_SOCKETS is turned on
and the kern.ipc.zero_copy.receive sysctl variable is
set to 1.
uipc_cow.c: Send side zero copy functions. Takes a page written
by the user and maps it copy on write and assigns it
kernel virtual address space. Removes copy on write
mapping once the buffer has been freed by the network
stack.
uipc_jumbo.c: Jumbo disposable page allocator code. This allocates
(optionally) disposable pages for network drivers that
want to give the user the option of doing zero copy
receive.
uipc_socket.c: Add kern.ipc.zero_copy.{send,receive} sysctls that are
enabled if ZERO_COPY_SOCKETS is turned on.
Add zero copy send support to sosend() -- pages get
mapped into the kernel instead of getting copied if
they meet size and alignment restrictions.
uipc_syscalls.c:Un-staticize some of the sf* functions so that they
can be used elsewhere. (uipc_cow.c)
if_media.c: In the SIOCGIFMEDIA ioctl in ifmedia_ioctl(), avoid
calling malloc() with M_WAITOK. Return an error if
the M_NOWAIT malloc fails.
The ti(4) driver and the wi(4) driver, at least, call
this with a mutex held. This causes witness warnings
for 'ifconfig -a' with a wi(4) or ti(4) board in the
system. (I've only verified for ti(4)).
ip_output.c: Fragment large datagrams so that each segment contains
a multiple of PAGE_SIZE amount of data plus headers.
This allows the receiver to potentially do page
flipping on receives.
if_ti.c: Add zero copy receive support to the ti(4) driver. If
TI_PRIVATE_JUMBOS is not defined, it now uses the
jumbo(9) buffer allocator for jumbo receive buffers.
Add a new character device interface for the ti(4)
driver for the new debugging interface. This allows
(a patched version of) gdb to talk to the Tigon board
and debug the firmware. There are also a few additional
debugging ioctls available through this interface.
Add header splitting support to the ti(4) driver.
Tweak some of the default interrupt coalescing
parameters to more useful defaults.
Add hooks for supporting transmit flow control, but
leave it turned off with a comment describing why it
is turned off.
if_tireg.h: Change the firmware rev to 12.4.11, since we're really
at 12.4.11 plus fixes from 12.4.13.
Add defines needed for debugging.
Remove the ti_stats structure, it is now defined in
sys/tiio.h.
ti_fw.h: 12.4.11 firmware.
ti_fw2.h: 12.4.11 firmware, plus selected fixes from 12.4.13,
and my header splitting patches. Revision 12.4.13
doesn't handle 10/100 negotiation properly. (This
firmware is the same as what was in the tree previously,
with the addition of header splitting support.)
sys/jumbo.h: Jumbo buffer allocator interface.
sys/mbuf.h: Add a new external mbuf type, EXT_DISPOSABLE, to
indicate that the payload buffer can be thrown away /
flipped to a userland process.
socketvar.h: Add prototype for socow_setup.
tiio.h: ioctl interface to the character portion of the ti(4)
driver, plus associated structure/type definitions.
uio.h: Change prototype for uiomoveco() so that we'll know
whether the source page is disposable.
ufs_readwrite.c:Update for new prototype of uiomoveco().
vm_fault.c: In vm_fault(), check to see whether we need to do a page
based copy on write fault.
vm_object.c: Add a new function, vm_object_allocate_wait(). This
does the same thing that vm_object allocate does, except
that it gives the caller the opportunity to specify whether
it should wait on the uma_zalloc() of the object structre.
This allows vm objects to be allocated while holding a
mutex. (Without generating WITNESS warnings.)
vm_object_allocate() is implemented as a call to
vm_object_allocate_wait() with the malloc flag set to
M_WAITOK.
vm_object.h: Add prototype for vm_object_allocate_wait().
vm_page.c: Add page-based copy on write setup, clear and fault
routines.
vm_page.h: Add page based COW function prototypes and variable in
the vm_page structure.
Many thanks to Drew Gallatin, who wrote the zero copy send and receive
code, and to all the other folks who have tested and reviewed this code
over the years.
obtained, when all other scheduling activity is suspended. This is needed
on sparc64 to deactivate the vmspace of the exiting process on all cpus.
Otherwise if another unrelated process gets the exact same vmspace structure
allocated to it (same address), its address space will not be activated
properly. This seems to fix some spontaneous signal 11 problems with smp
on sparc64.
Add a comment so that people don't forget to keep the
version in src/lib/libmd/md5c.c in sync with this one.
This fixes a warning on sparc64.
Reviewed by: phk
64-bit architectures that was introduced in the UFS2 code
merge two days ago. The stat structure change that caused
the problem was the addition of the file create time.
Submitted by: Bruce Evans <bde@zeta.org.au>
Sponsored by: DARPA & NAI Labs.
improperly clearing more then just the invalid portions of the page. (This
bug is not known to have been triggered by anything).
Submitted by: tegge
MFC after: 7 days
uio now that we don't use uiomove() anymore.
o Enforce stricter checks on the length of the iov's in
nmount(2) since we now malloc() them individually and
corrupted iov's could make the kernel crash in malloc()
with "kmem_map too small".
Reviewed by: phk
filesystem expands the inode to 256 bytes to make space for 64-bit
block pointers. It also adds a file-creation time field, an ability
to use jumbo blocks per inode to allow extent like pointer density,
and space for extended attributes (up to twice the filesystem block
size worth of attributes, e.g., on a 16K filesystem, there is space
for 32K of attributes). UFS2 fully supports and runs existing UFS1
filesystems. New filesystems built using newfs can be built in either
UFS1 or UFS2 format using the -O option. In this commit UFS1 is
the default format, so if you want to build UFS2 format filesystems,
you must specify -O 2. This default will be changed to UFS2 when
UFS2 proves itself to be stable. In this commit the boot code for
reading UFS2 filesystems is not compiled (see /sys/boot/common/ufsread.c)
as there is insufficient space in the boot block. Once the size of the
boot block is increased, this code can be defined.
Things to note: the definition of SBSIZE has changed to SBLOCKSIZE.
The header file <ufs/ufs/dinode.h> must be included before
<ufs/ffs/fs.h> so as to get the definitions of ufs2_daddr_t and
ufs_lbn_t.
Still TODO:
Verify that the first level bootstraps work for all the architectures.
Convert the utility ffsinfo to understand UFS2 and test growfs.
Add support for the extended attribute storage. Update soft updates
to ensure integrity of extended attribute storage. Switch the
current extended attribute interfaces to use the extended attribute
storage. Add the extent like functionality (framework is there,
but is currently never used).
Sponsored by: DARPA & NAI Labs.
Reviewed by: Poul-Henning Kamp <phk@freebsd.org>
a linked list. This is to allow the merging of the mount
options in the MNT_UPDATE case, as the current data structure
is unsuitable for this.
There are no functional differences in this commit.
Reviewed by: phk
implementations can provide a base zero ffs function if they wish.
This changes
#define RQB_FFS(mask) (ffs64(mask))
foo = RQB_FFS(mask) - 1;
to
#define RQB_FFS(mask) (ffs64(mask) - 1)
foo = RQB_FFS(mask);
On some platforms we can get the "- 1" for free, eg: those that use the
C code for ffs64().
Reviewed by: jake (in principle)
- Added a mutex, kld_mtx, to protect the kernel_linker system. Note that
while ``classes'' is global (to that file), it is only read only after
SI_SUB_KLD, SI_ORDER_ANY.
- Add a SYSINIT to flip a flag that disallows class registration after
SI_SUB_KLD, SI_ORDER_ANY.
Idea for ``classes'' read only by: jake
Reviewed by: jake
uifind() with a proc lock held.
change_ruid() and change_euid() have been modified to take a uidinfo
structure which will be pre-allocated by callers, they will then
call uihold() on the uidinfo structure so that the caller's logic
is simplified.
This allows one to call uifind() before locking the proc struct and
thereby avoid a potential blocking allocation with the proc lock
held.
This may need revisiting, perhaps keeping a spare uidinfo allocated
per process to handle this situation or re-examining if the proc
lock needs to be held over the entire operation of changing real
or effective user id.
Submitted by: Don Lewis <dl-freebsd@catspoiler.org>
operations to dump a ktrace event out to an output file are now handled
asychronously by a ktrace worker thread. This enables most ktrace events
to not need Giant once p_tracep and p_traceflag are suitably protected by
the new ktrace_lock.
There is a single todo list of pending ktrace requests. The various
ktrace tracepoints allocate a ktrace request object and tack it onto the
end of the queue. The ktrace kernel thread grabs requests off the head of
the queue and processes them using the trace vnode and credentials of the
thread triggering the event.
Since we cannot assume that the user memory referenced when doing a
ktrgenio() will be valid and since we can't access it from the ktrace
worker thread without a bit of hassle anyways, ktrgenio() requests are
still handled synchronously. However, in order to ensure that the requests
from a given thread still maintain relative order to one another, when a
synchronous ktrace event (such as a genio event) is triggered, we still put
the request object on the todo list to synchronize with the worker thread.
The original thread blocks atomically with putting the item on the queue.
When the worker thread comes across an asynchronous request, it wakes up
the original thread and then blocks to ensure it doesn't manage to write a
later event before the original thread has a chance to write out the
synchronous event. When the original thread wakes up, it writes out the
synchronous using its own context and then finally wakes the worker thread
back up. Yuck. The sychronous events aren't pretty but they do work.
Since ktrace events can be triggered in fairly low-level areas (msleep()
and cv_wait() for example) the ktrace code is designed to use very few
locks when posting an event (currently just the ktrace_mtx lock and the
vnode interlock to bump the refcoun on the trace vnode). This also means
that we can't allocate a ktrace request object when an event is triggered.
Instead, ktrace request objects are allocated from a pre-allocated pool
and returned to the pool after a request is serviced.
The size of this pool defaults to 100 objects, which is about 13k on an
i386 kernel. The size of the pool can be adjusted at compile time via the
KTRACE_REQUEST_POOL kernel option, at boot time via the
kern.ktrace_request_pool loader tunable, or at runtime via the
kern.ktrace_request_pool sysctl.
If the pool of request objects is exhausted, then a warning message is
printed to the console. The message is rate-limited in that it is only
printed once until the size of the pool is adjusted via the sysctl.
I have tested all kernel traces but have not tested user traces submitted
by utrace(2), though they should work fine in theory.
Since a ktrace request has several properties (content of event, trace
vnode, details of originating process, credentials for I/O, etc.), I chose
to drop the first argument to the various ktrfoo() functions. Currently
the functions just assume the event is posted from curthread. If there is
a great desire to do so, I suppose I could instead put back the first
argument but this time make it a thread pointer instead of a vnode pointer.
Also, KTRPOINT() now takes a thread as its first argument instead of a
process. This is because the check for a recursive ktrace event is now
per-thread instead of process-wide.
Tested on: i386
Compiles on: sparc64, alpha
lock_object by another pointer (though all of lock_object should be
conditional on LOCK_DEBUG anyways) in exchange for an O(1) TAILQ_REMOVE()
in witness_destroy() (called for every mtx_destroy() and sx_destroy())
instead of an O(n) STAILQ_REMOVE. Since WITNESS is so dog slow as it is,
the speed-up is worth the space cost.
Suggested by: iedowse
being created and destroyed without a single long-term one around to ensure
the witness associated with that group of locks stays alive. The pipe
mutexes are an example of this group. For a dead witness we no longer
clear the witness name. Instead, when looking up the witness for a lock,
if a dead witness' (a witness with a refcount of 0) w_name pointer is
identical to the witness name of the lock then we revive that witness
instead of using a new witness for the lock. This results in far fewer
dead witness objects and also better preserves locking orders over the long
term resulting in more correct lock order checking. Note that we can't
ever derefence w_name of a dead witness since we don't know if the string
it is pointing to has been free()'d or kldunload()'d out from under us.
daadr_t is no larger than a long, and some other relatively harmless
things (*blush*). Overflow for subtracting a daddr_t from a u_long
caused "truncation" of the i/o for attempts to access blocks beyond
the end of the actually cause expansion of the i/o to a preposterous
size.
simple reads (and on IA32, a "pause" instruction for each interation of the
loop) to spin until either the mutex owner field changes, or the lock owner
stops executing.
Suggested by: tanimura
Tested on: i386
(P_CONTINUED) is set when a stopped process receives a SIGCONT and
cleared after it has notified a parent process that has requested
notification via waitpid(2) with WCONTINUED specified in its options
operand. The status value can be checked with the new WIFCONTINUED()
macro.
Reviewed by: jake
set to zero. This field indicates the total space in the external buffer
and therefore should not be modified after the external buffer is added.
Add a comment warning that the mbufs returned by m_split() might be read-only.
Fix M_TRAILINGSPACE() to return zero if !M_WRITABLE(m).
Reviewed by: freebsd-net
Obtained from: Vernier Networks, Inc.
MFC after: 1 week
The uuidgen command, by means of the uuidgen syscall, generates one
or more Universally Unique Identifiers compatible with OSF/DCE 1.1
version 1 UUIDs.
From the Perforce logs (change 11995):
Round of cleanups:
o Give uuidgen() the correct prototype in syscalls.master
o Define struct uuid according to DCE 1.1 in sys/uuid.h
o Use struct uuid instead of uuid_t. The latter is defined
in sys/uuid.h but should not be used in kernel land.
o Add snprintf_uuid(), printf_uuid() and sbuf_printf_uuid()
to kern_uuid.c for use in the kernel (currently geom_gpt.c).
o Rename the non-standard struct uuid in kern/kern_uuid.c
to struct uuid_private and give it a slightly better definition
for better byte-order handling. See below.
o In sys/gpt.h, fix the broken uuid definitions to match the now
compliant struct uuid definition. See below.
o In usr.bin/uuidgen/uuidgen.c catch up with struct uuid change.
A note about byte-order:
The standard failed to provide a non-conflicting and
unambiguous definition for the binary representation. My initial
implementation always wrote the timestamp as a 64-bit little-endian
(2s-complement) integral. The clock sequence was always written
as a 16-bit big-endian (2s-complement) integral. After a good
nights sleep and couple of Pan Galactic Gargle Blasters (not
necessarily in that order :-) I reread the spec and came to the
conclusion that the time fields are always written in the native
by order, provided the the low, mid and hi chopping still occurs.
The spec mentions that you "might need to swap bytes if you talk
to a machine that has a different byte-order". The clock sequence
is always written in big-endian order (as is the IEEE 802 address)
because its division is resulting in bytes, making the ordering
unambiguous.
(UUIDs). On ia64 UUIDs, aka GUIDs, are used by EFI and the firmware
among others. To create GUID Partition Tables (GPTs), we need to
be able to generate UUIDs.
Make kern.ttys export a struct xtty rather than struct tty. Since struct
tty is no longer exposed to userland, remove the dev_t / udev_t hack.
Sponsored by: DARPA, NAI Labs
MI API with empty cpu_pause() functions on other arch's, but this
functionality is definitely unique to IA-32, so I decided to leave it
as i386-only and wrap it in #ifdef's. I should have dropped the cpu_
prefix when I made that decision.
Requested by: bde
Pentium 4's and newer IA32 processors. The "pause" instruction has been
verified by Intel to be a NOP on all currently existing IA32 processors
prior to the Pentium 4.
option is used (not on by default).
- In the case of trying to lock a mutex, if the MTX_CONTESTED flag is set,
then we can safely read the thread pointer from the mtx_lock member while
holding sched_lock. We then examine the thread to see if it is currently
executing on another CPU. If it is, then we keep looping instead of
blocking.
- In the case of trying to unlock a mutex, it is now possible for a mutex
to have MTX_CONTESTED set in mtx_lock but to not have any threads
actually blocked on it, so we need to handle that case. In that case,
we just release the lock as if MTX_CONTESTED was not set and return.
- We do not adaptively spin on Giant as Giant is held for long times and
it slows SMP systems down to a crawl (it was taking several minutes,
like 5-10 or so for my test alpha and sparc64 SMP boxes to boot up when
they adaptively spinned on Giant).
- We only compile in the code to do this for SMP kernels, it doesn't make
sense for UP kernels.
Tested on: i386, alpha, sparc64
yet. We just return without performing any checks.
- Don't explicitly enter and exit critical sections when walking lock
lists. We don't need a critical section to walk the list of sleep
locks for a thread. We check to see if a spin lock list is empty
before we walk it. If the list is empty we don't need to walk it. If
it isn't then we already hold at least one spin lock and are already in
a critical section and thus don't need our own explicit critical
section.
initialized socket with no qlimit was being passed in. In order
to handle this case properly, we must not use >= when comparing
queue sizes to qlimit. As a result of this improper handling,
a panic could result in certain cases.
PR: 38325
MFC after: 3 days
o Add a mutex (sb_mtx) to struct sockbuf. This protects the data in a
socket buffer. The mutex in the receive buffer also protects the data
in struct socket.
o Determine the lock strategy for each members in struct socket.
o Lock down the following members:
- so_count
- so_options
- so_linger
- so_state
o Remove *_locked() socket APIs. Make the following socket APIs
touching the members above now require a locked socket:
- sodisconnect()
- soisconnected()
- soisconnecting()
- soisdisconnected()
- soisdisconnecting()
- sofree()
- soref()
- sorele()
- sorwakeup()
- sotryfree()
- sowakeup()
- sowwakeup()
Reviewed by: alfred
pointer instead of a proc pointer and require the process pointed to
by the second argument to be locked. We now use the thread ucred reference
for the credential checks in p_can*() as a result. p_canfoo() should now
no longer need Giant.
inter-process signalling ceased to preserve and return that value,
instead always returning EPERM. This meant that it was possible
to "probe" the pid space for processes that were not otherwise
visible. This change reverts that reversion.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
out-of-range, drop the file reference before returning. (This error
also exists in the RELENG_4 branch.)
o Eliminate the acquisition and release of Giant in readv()
now that malloc() and free() are callable without Giant.
.) don't use MAXPATHLEN + 1, fix logic to compensate.
.) style(9) function parameters.
.) fix line wrapping.
.) remove duplicated error and string handling code.
.) don't NUL terminate already NUL terminated string.
.) all string length variables changed from int to size_t.
.) constify variables.
.) catch when corename would be truncated.
.) cast pid_t and uid_t args for format string.
.) add parens around return arguments.
Help and suggestions from: bde
on committing to these while they were in the Attic after they had been
removed. I think this was because he had the file checked out and already
'modified' while markm cvs rm'ed them, and cvs screws up when trying to
"merge" the modifications with the "rm". And after that the client
state was sufficiently hosed to keep it messed up. Yay CVS! (CVS is
very fragile for adding and removing files remotely)
The existence of these files was pointed out by: ru
be done internally.
Ensure that no one can fsetown() to a dying process/pgrp. We need
to check the process for P_WEXIT to see if it's exiting. Process
groups are already safe because there is no such thing as a pgrp
zombie, therefore the proctree lock completely protects the pgrp
from having sigio structures associated with it after it runs
funsetownlst.
Add sigio lock to witness list under proctree and allproc, but over
proc and pgrp.
Seigo Tanimura helped with this.
Don't try to create a vm object before the file system has a chance to finish
initializing it. This is incorrect for a number of reasons. Firstly, that
VOP requires a lock which the file system may not have initialized yet. Also,
open and others will create a vm object if it is necessary later.
killed by SIGSYS for unimlemented syscalls is bad enough.
Obtained from: Lite2 branch
The Lite2 branch has some other interesting unmerged (?) bits in this
file. They are well hidden among cosmetic regressions.
sys/time.h rev.1.53, etc. Zero out the entire struct clkinfo and not
just the new spare part of it so that there is no possibility of leaking
kernel stack context to userland.
- Reorder fork1() to do malloc() and other blocking operations prior to
acquiring the needed process locks.
- The new process inherit's the credentials of curthread, not the
credentials of the old process.
- Document a really weird race that will come up with KSE allows multiple
kernel threads per process.
exit1() we don't have to release it until we acquire schd_lock to
call cpu_throw().
- Since we can switch at any time due to preemption or a lock release
prior to acquiring sched_lock, don't update switchtime and switchticks
until the very end of exit1() after we have acquired sched_lock.
- Interlock the proctree_lock and proc lock in wait1() and exit1() to
avoid lost wakeups when a parent blocks waiting for a child to exit at
the bottom of wait1(). In exit1() the proc lock interlocked with
proctree_lock (and released after acquiring sched_lock) is that of
the parent process.
- In wait1() use an exclusive lock of proctree lock while we are
looking for a process to harvest. This allows us to completely
remove all references to the process once we've found one (i.e.,
disconnect it from pgrp's, session's, zombproc list, and it's parent's
children list) "atomically" without needing to worry about a lock
upgrade.
- We don't need sched_lock to test if p_stat is SZOMB or SSTOP when holding
the proc lock since the proc lock is always held with p_stat is set to
SZOMB or SSTOP.
- Protect nprocs with an xlock of the allproc_lock.
locks the process.
- Defer other blocking operations such as vrele()'s until after we
release locks.
- execsigs() now requires the proc lock to be held when it is called
rather than locking the process internally.
mallochash. Mallochash is going to go away as soon as I introduce the
kfree/kmalloc api and partially overhaul the malloc wrapper. This can't happen
until all users of the malloc api that expect memory to be aligned on the size
of the allocation are fixed.
Implement the following checks on freed memory in the bucket path:
- Slab membership
- Alignment
- Duplicate free
This previously was only done if we skipped the buckets. This code will slow
down INVARIANTS a bit, but it is smp safe. The checks were moved out of the
normal path and into hooks supplied in uma_dbg.
Turn the sigio sx into a mutex.
Sigio lock is really only needed to protect interrupts from dereferencing
the sigio pointer in an object when the sigio itself is being destroyed.
In order to do this in the most unintrusive manner change pgsigio's
sigio * argument into a **, that way we can lock internally to the
function.
loading breakage'). The patch fixes serious issues with the VFS
operations vector array which results in a crash when a filesystem module
adding a new VOP is loaded into the kernel. Basically what was happening
before was that the old operations vector was being freed and a new one
allocated. The original MALLOC code tended to reuse the same address
for the case and so the bug did not rear its ugly head until the new memory
subsystem was emplaced.
This patch replaces the temporary workaround Dave O'Brien comitted in 1.58.
The patch is clean enough that I intend to MFC it to stable at some point.
Submitted by: Alexander Kabaev <ak03@gte.com>
MFC after: 1 week
0xdeadc0de and then check for it just before memory is handed off as part
of a new request. This will catch any post free/pre alloc modification of
memory, as well as introduce errors for anything that tries to dereference
it as a pointer.
This code takes the form of special init, fini, ctor and dtor routines that
are specificly used by malloc. It is in a seperate file because additional
debugging aids will want to live here as well.
Requested by: bde
Since locking sigio_lock is usually followed by calling pgsigio(),
move the declaration of sigio_lock and the definitions of SIGIO_*() to
sys/signalvar.h.
While I am here, sort include files alphabetically, where possible.
malloc profiling) also modified the set of pre-defined buckets for the
memory allocator. For reasons unknown to me, this resulted in extensive
memory corruption in the kernel, in particular on SMP boxes, so I'm
committing this work-around until Jeff gets a chance to debug it
properly. David Wolfskill pointed me at this commit as the one that
might be a problem; I've been running this code on two dual-processor
burn-in boxes for about 12 hours now, and the rate of panics due to
memory corruption has dropped to zero (from one every five minutes).
Hopefully not treading on the toes of: jeff
SIGCHLD handler is SIG_IGN. This is a reimplementation of the
problematic revision 1.131 of kern_exit.c. To avoid accessing process
UPAGES, we set a new procsig flag when the SIGCHLD handler is SIG_IGN
and use that instead.
Otherwise we fall back to using the static hints the next time around.
We still have the leftover fallback code there which meant that we skipped
the use_hints checking on the second and subsequent calls. Also, be a bit
more careful about walking off the end of the envp array.
I've extracted this from a larger diff. I hope I didn't miss anything...
of a socket. This avoids lock order reversal caused by locking a
process in pgsigio().
sowakeup() and the callers of it (sowwakeup, soisconnected, etc.) now
require sigio_lock to be locked. Provide sowwakeup_locked(),
soisconnected_locked(), and so on in case where we have to modify a
socket and wake up a process atomically.
by other bits of code, split struct timecounter into two.
struct timecounter contains just the bits which pertains to the hardware
counter and the reading of it.
struct timehands (as in "the hands on a clock") contains all the ugly bit
fidling stuff. Statically compile ten timehands.
This commit is the functional part. A later cosmetic patch will rename
various variables and fieldnames.
timeout loop.
Limit the rate at which we wind the timecounters to approx 1000 Hz.
This limits the precision of the get{bin,nano,micro}[up]time(9)
functions to roughly a millisecond.
timecounter will be used starting at the next second, which is
good enough for sysctl purposes. If better adjustment is needed
the NTP PLL should be used.
LRU fashion when the listen queue fills up. Previously, there was
no mechanism to kick out old sockets, leading to an easy DoS of
daemons using accept filtering.
Reviewed by: alfred
MFC after: 3 days
- malformed environment strings (ones without an '=') were not rejected.
There shouldn't be any of these, but when the static environment is
empty it always begins with one of these; this one should be considered
as the terminator after the end of the environment, but it isn't.
- the comparison of the name being looked up with the name in the
environment was fuzzy -- only the characters up to the length of the
latter were compared, so _getenv_static("foobar") matched "foo=..."
in the environment and everything matched "" in the empty environment.
MFC after: 3 days
#!bin/sh
# Original version of this by Michael Reifenberger
# <root@nihil.plaut.de>.
mdconfig -d -u 11 >/dev/null 2>&1
dd if=/dev/zero of=zz bs=1m count=1
while :
do
mdconfig -a -t vnode -f zz -u 11
fdisk -f - -iv /dev/md11 <<EOF1
g c1 h64 s32
p 1 165 0 2048
a 1
EOF1
mdconfig -d -u 11
done
Garbage pointers in __si_u were not cleared by destroy_dev(). Not
clearing si_disk made the above fatal because the disk layer uses
si_disk as a flag to indicate that the dev_t has been completely
initialized. disk_destroy() clears si_disk for the parent dev_t
but doesn't get called for children.
Not fixed:
- setting the undocumented sysctl debug.free_devt should cause more
complete destruction of the dev_t including clearing of __si_u, but
actually causes the above to panic a little earlier.
- the loop leaks 10 memory allocations per iteration (4 DEVFS, 2 devbuf
and 4 dev_t).
Reviewed by: timeout by MAINTAINER after 3 months
the symbol index defined by the relocation. The elf_lookup() support
function is to be used by elf_reloc() when symbol lookups need to be
done. The elf_lookup() function operates on the symbol index and
will do a symbol name based lookup when such is required, otherwise
it uses the symbol index directly. This solves the problem seen on
ia64 where the symbol hash table does not contain local symbols and
a symbol name based lookup would fail for those symbols.
Don't pass the symbol name to elf_reloc(), as it isn't used any more.
civilized way which doesn't cause grief.
The problem is that it is not generally safe to cast a "struct bio
*" to a "struct buf *". Things like ccd, vinum, ata-raid and GEOM
constructs bio's which are not entrails of a struct buf.
Also, curthread may or may not have anything to do with the I/O request
at hand.
The correct solution can either be to tag struct bio's with a
priority derived from the requesting threads nice and have disksort
act on this field, this wouldn't address the "silly-seek syndrome"
where two equal processes bang the diskheads from one edge to the
other of the disk repeatedly.
Alternatively, and probably better: a sleep should be introduced
either at the time the I/O is requested or at the time it is completed
where we can be sure to sleep in the right thread.
The sleep also needs to be in constant timeunits, 1/hz can be practicaly
any sub-second size, at high HZ the current code practically doesn't
do anything.
the DT_PLTGOT value. On ia64 this is the value of GP. We need this
to construct function descriptors, but the elf file structure is
not exported to MD code.
Note that the name of the function is based on the meaning that
DT_PLTGOT has on ia64. This may differ on other architectures. As
such, link_elf_get_gp() has a high level of MD to it. Renaming the
function to describe what DT_* value is returned makes it generic,
but also makes the MD code less clear and if we only need this on
ia64, then a general name for a specific function doesn't help.
In short: I don't know what is "right" at this time, so I'll go
with what I have.
in various extattr_*() calls to match the rest of the file. Originally,
these bits at the end looked more like style(9). This patch was submitted
by green by way of the TrustedBSD MAC tree, and I fixed a few problems
with it on the way through. Someone with more time on their hands should
convert the entire file to style(9); this commit is for diff reduction
purposes.
Submitted by: green
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
constructing a struct aio and invoking VOP_READ() directly. This cleans
up the code a little, but also has the advantage of making sure almost
all vnode read/write access in the kernel goes through the helper
function, meaning that instrumentation of that helper function can impact
almost all relevant read/write operations. In this case, it permits us
to put MAC hooks into vn_rdwr() and not modify uipc_syscalls.c (yet).
In general, if helper vn_*() functions exist, they should be used in
preference to direct VOP's in system call service code.
Submitted by: green
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
needed in the current code, in the MAC tree, create_init() relies on the
ability to modify the credentials present for initproc, and should not
perform that modification on a shared credential. Pro-active diff
reduction against MAC changes that are in the queue; also facilitates
other work, including the capabilities implementation.
Submitted by: green
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
environment needed at boot time to a dynamic subsystem when VM is
up. The dynamic kernel environment is protected by an sx lock.
This adds some new functions to manipulate the kernel environment :
freeenv(), setenv(), unsetenv() and testenv(). freeenv() has to be
called after every getenv() when you have finished using the string.
testenv() only tests if an environment variable is present, and
doesn't require a freeenv() call. setenv() and unsetenv() are self
explanatory.
The kenv(2) syscall exports these new functionalities to userland,
mainly for kenv(1).
Reviewed by: peter
where some client operations might be unexpectedly cancelled during
an unsuccessful non-forced unmount attempt. This causes problems
for amd(8), because it periodically attempts a non-forced unmount
to check if the filesystem is still in use.
Fix this by adding a new mountpoint flag MNTK_UNMOUNTF that is set
only during the operation of a forced unmount. Use this instead of
MNTK_UNMOUNT to trigger the cancellation of hung NFS operations.
Also correct a problem where dounmount() might inadvertently clear
the MNTK_UNMOUNT flag.
Reported by: simokawa
MFC after: 1 week
- Use temporary variables to hold a pointer to a pgrp while we dink with it
while not holding either the associated proc lock or proctree_lock. It
is in theory possible that p->p_pgrp could change out from under us.
