This allows blind increment of relevant counters which under contention
is cheaper than inc-not-zero loops at least on amd64.
Use it in some of the places which are guaranteed to see already active
vnodes.
Reviewed by: kib (previous version)
As of r234483, vnode deactivation causes non-VPO_NOSYNC pages to be
laundered. This behaviour has two problems:
1. Dirty VPO_NOSYNC pages must be laundered before the vnode can be
reclaimed, and this work may be unfairly deferred to the vnlru process
or an unrelated application when the system is under vnode pressure.
2. Deactivation of a vnode with dirty VPO_NOSYNC pages requires a scan of
the corresponding VM object's memq for non-VPO_NOSYNC dirty pages; if
the laundry thread needs to launder pages from an unreferenced such
vnode, it will reactivate and deactivate the vnode with each laundering,
potentially resulting in a large number of expensive scans.
Therefore, ensure that all dirty pages are laundered upon deactivation,
i.e., when all maps of the vnode are removed and all references are
released.
Reviewed by: alc, kib
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D8641
Previously free vnodes would always by directly returned to the global
LRU list. With this change up to mnt_free_list_batch vnodes are collected
first.
syncer runs always return the batch regardless of its size.
While vnodes on per-mnt lists are not counted as free, they can be
returned in case of vnode shortage.
Reviewed by: kib
Tested by: pho
if vnode is VMIO. For VMIO vnodes, set BO_DEAD in vm_object_terminate().
The vnode_destroy_object(), when calling into vm_object_terminate(),
must be able to flush buffers. BO_DEAD purpose is to quickly destroy
buffers on write when the underlying vnode is not operable any more
(one example is the devfs node after geom is gone). Setting BO_DEAD
for reclaiming vnode before object is terminated is premature, and
results in unability to flush buffers with live SU dependencies from
vinvalbuf() in vm_object_terminate().
Reported by: David Cross <dcrosstech@gmail.com>
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
does it under the vnode interlock, but the interlock is not owned by the
asserting thread. As result, we might read increased use counter but also
still see VI_OWEINACT.
In collaboration with: nwhitehorn
Hardware donated by: IBM LTC
Sponsored by: The FreeBSD Foundation (kib)
Approved by: re (gjb)
to mount points with the given filesystem type, specified by mount
vfs_ops pointer.
Based on patch by: mckusick
Reviewed by: avg, mckusick
Tested by: allanjude, madpilot
Sponsored by: The FreeBSD Foundation
Approved by: re (gjb)
It seems that at present vfs_read_dirent() is used only with filesystems
that do not support cookies, so the bug never manifested itself.
MFC after: 1 week
While there, order EVFILT_VNODE notes descriptions alphabetically.
Based on submission, and tested by: Vladimir Kondratyev <wulf@cicgroup.ru>
MFC after: 2 weeks
the monitored directory as the result of rename(2) operation. The
renames staying in the directory are not reported.
Submitted by: Vladimir Kondratyev <wulf@cicgroup.ru>
MFC after: 2 weeks
rename removing or adding subdirectory entry.
Discussed with and tested by: Vladimir Kondratyev <wulf@cicgroup.ru>
NetBSD PR: 48958 (http://gnats.netbsd.org/48958)
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
the virtvnodes calculation. Include the size of fs-specific v_data as
the nfs nclnode inline, the NFS nclnode is bigger than either ZFS
znode or UFS inode. Include the size of namecache_ts and short cache
path element, multiplied by the name cache population factor, again
inline.
Inline defines are used to avoid pollution of the vnode.h with the
subsystem-private objects. Non-significant unsynchronized changes of
the definitions are fine, we do not care about that precision, and
e.g. ZFS consumes much malloced memory per vnode for reasons
unaccounted in the formula.
Lower the partition of kmem dedicated to vnodes, from 1/7 to 1/10.
The measures reduce vnode cache pressure on kmem and bring the vnode
cache memory use below some apparent thresholds that were exceeded by
r291244 due to more robust vnode reuse.
Reported and tested by: marius (i386, previous version)
Reviewed by: bde
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
numbers range.
This effectively skips indirect and extdata blocks on the buffer
queue. Since their logical block numbers are negative, bnoreuselist()
could loop infinitely.
Reported and tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
This API has no in-tree consumers at the moment but is useful to at least
one out-of-tree consumer, and naturally complements existing vnode refcount
functions (vholdl(9), vdropl(9)).
Obtained from: kib (sys/ portion)
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D4947
Differential Revision: https://reviews.freebsd.org/D4953
Advance the logical block number to the lblkno of the found block plus
one, instead of incrementing the block number which was used for
lookup. This change skips sparcely populated buffer ranges, similar
to r292325, instead of doing useless lookups.
Do not restart the bnoreuselist() from the start of the range if
buffer lock cannot be obtained without sleep. Only retry lookup and
lock for the same queue and same logical block number.
Reported by: benno
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
buffer for each block number in the range with gbincore(), look up the
next instantiated buffer with the logical block number which is
greater or equal to the next lblkno. This significantly speeds up the
iteration for sparce-populated range.
Move the iteration into new helper bnoreuselist(), which is structured
similarly to flushbuflist().
Reported and tested by: pho
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
the type stability of the buffers memory. Instead of memoizing
pointer to the next buffer and validating it, remember the next
logical block number in the bo list and re-lookup.
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
For completeness add a VNASSERT that there are no threads waiting on a
range lock (this was previously checked on every vnode free).
Reported by; Rick Macklem
Fix from: Mateusz Guzik
PR: 204949
on every allocation and fully releases them on every free. These
are not trivial costs: it starts by zeroing a large structure then
initializes a mutex, a lock manager lock, an rw lock, four lists,
and six pointers. And looking at vfs.vnodes_created, these operations
are being done millions of times an hour on a busy machine.
As a performance optimization, this code update uses the uma_init
and uma_fini routines to do these initializations and cleanups only
as the vnodes enter and leave the vnode_zone. With this change the
initializations are only done kern.maxvnodes times at system startup
and then only rarely again. The frees are done only if the vnode_zone
shrinks which never happens in practice. For those curious about the
avoided work, look at the vnode_init() and vnode_fini() functions in
kern/vfs_subr.c to see the code that has been removed from the main
vnode allocation/free path.
Reviewed by: kib
Tested by: Peter Holm
active list, into the header comment for vdrop(), which is the
function that decides whether to leave the vnode on the list. Note
that dirty page write-out in vinactive() is asynchronous.
Discussed with: alc
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
targets. See the comment above wantfreevnodes variable for the
description of the algorithm.
The vfs.vlru_alloc_cache_src sysctl is removed. New code frees
namecache sources as the last chance to satisfy the highest watermark,
instead of selecting the source vnodes randomly. This provides good
enough behaviour to keep vn_fullpath() working in most situations.
The filesystem layout with deep trees, where the removed knob was
required, is thus handled automatically.
Submitted by: bde
Discussed with: mckusick
Tested by: pho
MFC after: 1 month
In poll mode, check for and wake VBAD vnodes. (Vnodes that are VBAD at
registration will never be woken by the RECLAIM trigger.)
Add post-VOP_RECLAIM hook to trigger notes on vnode reclamation. (Vnodes that
were fine at registration but are vgoned while being monitored should signal
waiters.)
Reviewed by: kib
Approved by: markj (mentor)
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D3675
the size of the name cache hash table (mapping file names to vnodes)
and the vnode hash table (mapping mount point and inode number to vnode).
An appropriate locking strategy is the key to changing hash table sizes
while they are in active use.
Reviewed by: kib
Tested by: Peter Holm
Differential Revision: https://reviews.freebsd.org/D2265
MFC after: 2 weeks
reason this didn't result in an unclean shutdown is that devfs ignores
MNT_FORCE flag.
Reviewed by: kib@
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3467
It looks like EVFILT_READ and EVFILT_WRITE trigger under the same
conditions as poll()'s POLLRDNORM and POLLWRNORM as described by POSIX.
The only difference is that POLLRDNORM has to be triggered on regular
files unconditionally, whereas EVFILT_READ only triggers when not EOF.
Introduce a new flag, NOTE_FILE_POLL, that can be used to make
EVFILT_READ and EVFILT_WRITE behave identically to poll(). This flag
will be used by cloudlibc's poll() function.
Reviewed by: jmg
Differential Revision: https://reviews.freebsd.org/D3303
Transitions 0->1 and 1->0 (which decide e.g. on putting the vnode on the free
list) of either counter are still guarded with vnode interlock.
Reviewed by: kib (earlier version)
Tested by: pho
Previously vputx would detect the condition and clear the flag.
With this change it is invalid to have both v_usecount > 0 and the flag
set. Assert the condition is met in all revlevant places.
Reviewed by: kib
