path through the NFS clients' getpages functions.
Introduce vm_pager_free_nonreq(). This function can be used to eliminate
code that is duplicated in many getpages functions. Also, in contrast to
the code that currently appears in those getpages functions,
vm_pager_free_nonreq() avoids acquiring an exclusive object lock in one
case.
Reviewed by: kib
MFC after: 6 weeks
Sponsored by: EMC / Isilon Storage Division
option, unbreak the lock tracing release semantic by embedding
calls to LOCKSTAT_PROFILE_RELEASE_LOCK() direclty in the inlined
version of the releasing functions for mutex, rwlock and sxlock.
Failing to do so skips the lockstat_probe_func invokation for
unlocking.
- As part of the LOCKSTAT support is inlined in mutex operation, for
kernel compiled without lock debugging options, potentially every
consumer must be compiled including opt_kdtrace.h.
Fix this by moving KDTRACE_HOOKS into opt_global.h and remove the
dependency by opt_kdtrace.h for all files, as now only KDTRACE_FRAMES
is linked there and it is only used as a compile-time stub [0].
[0] immediately shows some new bug as DTRACE-derived support for debug
in sfxge is broken and it was never really tested. As it was not
including correctly opt_kdtrace.h before it was never enabled so it
was kept broken for a while. Fix this by using a protection stub,
leaving sfxge driver authors the responsibility for fixing it
appropriately [1].
Sponsored by: EMC / Isilon storage division
Discussed with: rstone
[0] Reported by: rstone
[1] Discussed with: philip
option. This can occur when an nfsiod thread that already holds
a buffer lock attempts to acquire a vnode lock on an entry in
the directory (a LOR) when another thread holding the vnode lock
is waiting on an nfsiod thread. This patch avoids the deadlock by disabling
readahead for this case, so the nfsiod threads never do readdirplus.
Since readaheads for directories need the directory offset cookie
from the previous read, they cannot normally happen in parallel.
As such, testing by jhb@ and myself didn't find any performance
degredation when this patch is applied. If there is a case where
this results in a significant performance degradation, mounting
without the "rdirplus" option can be done to re-enable readahead
for directories.
Reported and tested by: jhb
Reviewed by: jhb
MFC after: 2 weeks
In common configurations biosize is a power of two, but is not required to
be so. Thanks to markj@ for spotting an additional case beyond my original
patch.
Reviewed by: rmacklem@
future further optimizations where the vm_object lock will be held
in read mode most of the time the page cache resident pool of pages
are accessed for reading purposes.
The change is mostly mechanical but few notes are reported:
* The KPI changes as follow:
- VM_OBJECT_LOCK() -> VM_OBJECT_WLOCK()
- VM_OBJECT_TRYLOCK() -> VM_OBJECT_TRYWLOCK()
- VM_OBJECT_UNLOCK() -> VM_OBJECT_WUNLOCK()
- VM_OBJECT_LOCK_ASSERT(MA_OWNED) -> VM_OBJECT_ASSERT_WLOCKED()
(in order to avoid visibility of implementation details)
- The read-mode operations are added:
VM_OBJECT_RLOCK(), VM_OBJECT_TRYRLOCK(), VM_OBJECT_RUNLOCK(),
VM_OBJECT_ASSERT_RLOCKED(), VM_OBJECT_ASSERT_LOCKED()
* The vm/vm_pager.h namespace pollution avoidance (forcing requiring
sys/mutex.h in consumers directly to cater its inlining functions
using VM_OBJECT_LOCK()) imposes that all the vm/vm_pager.h
consumers now must include also sys/rwlock.h.
* zfs requires a quite convoluted fix to include FreeBSD rwlocks into
the compat layer because the name clash between FreeBSD and solaris
versions must be avoided.
At this purpose zfs redefines the vm_object locking functions
directly, isolating the FreeBSD components in specific compat stubs.
The KPI results heavilly broken by this commit. Thirdy part ports must
be updated accordingly (I can think off-hand of VirtualBox, for example).
Sponsored by: EMC / Isilon storage division
Reviewed by: jeff
Reviewed by: pjd (ZFS specific review)
Discussed with: alc
Tested by: pho
network file systems (not only NFS proper). Short reads cause pages
other then the requested one, which were not filled by read response,
to stay invalid.
Change the vm_page_readahead_finish() interface to not take the error
code, but instead to make a decision to free or to (de)activate the
page only by its validity. As result, not requested invalid pages are
freed even if the read RPC indicated success.
Noted and reviewed by: alc
MFC after: 1 week
to pull vm_param.h was removed. Other big dependency of vm_page.h on
vm_param.h are PA_LOCK* definitions, which are only needed for
in-kernel code, because modules use KBI-safe functions to lock the
pages.
Stop including vm_param.h into vm_page.h. Include vm_param.h
explicitely for the kernel code which needs it.
Suggested and reviewed by: alc
MFC after: 2 weeks
vm_page oflags by providing helper function
vm_page_readahead_finish(), which handles completed reads for pages
with indexes other then the requested one, for VOP_GETPAGES().
Reviewed by: alc
MFC after: 1 week
memory mapped pages being written back on an NFS mount.
Since any thread can call VOP_PUTPAGES() to write back a
dirty page, the credentials of that thread may not have
write access to the file on an NFS server. (Often the uid
is 0, which may be mapped to "nobody" in the NFS server.)
Although there is no completely correct fix for this
(NFS servers check access on every write RPC instead of at
open/mmap time), this patch avoids the common cases by
holding onto a credential that recently opened the file
for writing and uses that credential for the write RPCs
being done by VOP_PUTPAGES() for both NFS clients.
Tested by: Joel Ray Holveck (joelh at juniper.net)
PR: kern/165923
Reviewed by: kib
MFC after: 2 weeks
Add the sysctl debug.iosize_max_clamp, enabled by default. Setting the
sysctl to zero allows to perform the SSIZE_MAX-sized i/o requests from
the usermode.
Discussed with: bde, das (previous versions)
MFC after: 1 month
NFS clients was reported to freebsd-fs@ under the subject "NFS
corruption in recent HEAD" on Nov. 26, 2011. This problem occurred when
a TCP mounted root fs was changed to using UDP. I believe that this
problem was caused by the change in mnt_stat.f_iosize that occurred
because rsize was decreased to the maximum supported by UDP. This
patch fixes the problem by using v_bufobj.bo_bsize instead of f_iosize,
since the latter is set to f_iosize when the vnode is allocated, but
does not change for a given vnode when f_iosize changes.
Reported by: pjd
Reviewed by: kib
MFC after: 2 weeks
Allow the NFS client to use a max file size larger than 1TB for v3 mounts.
It now allows files up to OFF_MAX subject to whatever limit the server
advertises.
Reviewed by: rmacklem
Approved by: re (kib)
MFC after: 1 week
VM_PAGER_AGAIN to VM_PAGER_ERROR for the uwritten pages. Return
VM_PAGER_AGAIN for the partially written page. Always forward at least
one page in the loop of vm_object_page_clean().
VM_PAGER_ERROR causes the page reactivation and does not clear the
page dirty state, so the write is not lost.
The change fixes an infinite loop in vm_object_page_clean() when the
filesystem returns permanent errors for some page writes.
Reported and tested by: gavin
Reviewed by: alc, rmacklem
MFC after: 1 week
fixed the issues with file descriptor locks, but the same problems are
present for vnode lock/user map lock.
If the nfs_asyncio() cannot find the free nfsiod, schedule task to
create new nfsiod and return error. This causes fall back to the
synchronous i/o for nfs_strategy(), or does not start read at all in
the case of readahead. The caller that holds vnode and potentially
user map lock does not wait for kproc_create() to finish, preventing
the LORs.
The change effectively reverts r203072, because we never hand off the
request to newly created nfsiod thread anymore.
Reviewed by: jhb
Tested by: jhb, pluknet
MFC after: 3 weeks
DIAGNOSTIC and #ifndef DIAGNOSTIC for debug assertions, prefer
KASSERT(). Also change one #ifdef DIAGNOSTIC in the new nfs server.
Submitted by: Mikolaj Golub <to.my.trociny gmail com>
MFC after: 2 weeks
managed pages that didn't already have that lock held. (Freeing an
unmanaged page, such as the various pmaps use, doesn't require the page
lock.)
This allows a change in vm_page_remove()'s locking requirements. It now
expects the page lock to be held instead of the page queues lock.
Consequently, the page queues lock is no longer required at all by callers
to vm_page_rename().
Discussed with: kib
Without this patch it was possible for a different thread that calls
nfs_asyncio() to snitch a newly created nfsiod thread that was
intended for another caller of nfs_asyncio(), because the nfs_iod_mtx
mutex was unlocked while the new nfsiod thread was created. This patch
labels the newly created nfsiod, so that it is not taken by another
caller of nfs_asyncio(). This is believed to fix the problem reported
on the freebsd-stable email list under the subject:
FreeBSD NFS client/Linux NFS server issue.
Tested by: to DOT my DOT trociny AT gmail DOT com
Reviewed by: jhb
MFC after: 2 weeks
kernel resources that block other threads, like vnode locks. The SIGSTOP
sent to such thread (process, rather) shall not stop it until thread
releases the resources.
Tested by: pho
Reviewed by: jhb
Approved by: re (kensmith)
nfs_bioread_check_cons(). This is required since it is possible
for the vnode to be vgonel()'d while in nfs_upgrade_vnlock() when
a forced dismount is in progress. Also, move the check for VI_DOOMED
in nfs_vinvalbuf() down to after nfs_upgrade_vnlock() and replace the
out of date comment for it.
Submitted by: jhb
Tested by: pho
Approved by: kib (mentor)
MFC after: 1 month
events are:
nfsclient:accesscache:flush:done
nfsclient:accesscache:get:hit
nfsclient:accesscache:get:miss
nfsclient:accesscache:load:done
They pass the vnode, uid, and requested or loaded access mode (if any);
the load event may also report a load error if the RPC fails.
The attribute cache events are:
nfsclient:attrcache:flush:done
nfsclient:attrcache:get:hit
nfsclient:attrcache:get:miss
nfsclient:attrcache:load:done
They pass the vnode, optionally the vattr if one is present (hit or load),
and in the case of a load event, also a possible RPC error.
MFC after: 1 month
Sponsored by: Google, Inc.
In particular following functions KPI results modified:
- bufobj_invalbuf()
- bufsync()
and BO_SYNC() "virtual method" of the buffer objects set.
Main consumers of bufobj functions are affected by this change too and,
in particular, functions which changed their KPI are:
- vinvalbuf()
- g_vfs_close()
Due to the KPI breakage, __FreeBSD_version will be bumped in a later
commit.
As a side note, please consider just temporary the 'curthread' argument
passing to VOP_SYNC() (in bufsync()) as it will be axed out ASAP
Reviewed by: kib
Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
owned by a NULL owner. This will lead consequent VOP_ISLOCKED() present
into nfs_upgrade_vnlock() to panic as it only acquire curthread now.
Fix nfs_upgrade_vnlock() and nfs_downgrade_vnlock() in order to not use
more the struct thread pointer passed as argument (as it is really nomore
required there as vn_lock() and VOP_UNLOCK doesn't get the lock more).
Using curthread, in place, doesn't get ambiguity as LK_EXCLOTHER should
be handled as a "not locked" request by both functions.
Reported by: kris
Tested by: kris
Reviewed by: ups
timeout occurring at exactly the same time. If this happens, the nfsiod
exits although there may be a queued async IO request for it.
Found by : Kris Kennaway
Approved by: re
recoverable and unrecoverable. For the former, we redirty the
buffer and hang onto it for future retries. For the latter (eg.
ESTALE), we discard the buffer and return the error back to the
user on the next syscall. This fixes a number of vfs panics and
fixes having a large number of dirty buffers (that cannot be
written out and reclaimed) from hanging around. Thanks to ups@
for discussions on this issue.
Reported by: kris, Kai, others
Approved by: re (kensmith)
Now, we assume no more sched_lock protection for some of them and use the
distribuited loads method for vmmeter (distribuited through CPUs).
Reviewed by: alc, bde
Approved by: jeff (mentor)
Probabilly, a general approach is not the better solution here, so we should
solve the sched_lock protection problems separately.
Requested by: alc
Approved by: jeff (mentor)
vmcnts. This can be used to abstract away pcpu details but also changes
to use atomics for all counters now. This means sched lock is no longer
responsible for protecting counts in the switch routines.
Contributed by: Attilio Rao <attilio@FreeBSD.org>
- Fix for a bug where a close would not wait for all (directio)
dirty buffers to drain. The nfsnode was not marked NMODIFIED
when there were directio dirtied buffers pending, causing this.
- No reason to vhold/vrele the vp when enqueueing DirectIO requests
for the nfsiods. The vnode can't really go way since the close
has to wait for these requests to drain.
MFC after: 1 week
Submitted by: mohans
synchronized by the lock on the object containing the page.
Transition PG_WANTED and PG_SWAPINPROG to use the new field,
eliminating the need for holding the page queues lock when setting
or clearing these flags. Rename PG_WANTED and PG_SWAPINPROG to
VPO_WANTED and VPO_SWAPINPROG, respectively.
Eliminate the assertion that the page queues lock is held in
vm_page_io_finish().
Eliminate the acquisition and release of the page queues lock
around calls to vm_page_io_finish() in kern_sendfile() and
vfs_unbusy_pages().
If B_NOCACHE is set the pages of vm backed buffers will be invalidated.
However clean buffers can be backed by dirty VM pages so invalidating them
can lead to data loss.
Add support for flush dirty page in the data invalidation function
of some network file systems.
This fixes data losses during vnode recycling (and other code paths
using invalbuf(*,V_SAVE,*,*)) for data written using an mmaped file.
Collaborative effort by: jhb@,mohans@,peter@,ps@,ups@
Reviewed by: tegge@
MFC after: 7 days
