This commit partially reverts r273641 which introduced the leak.
It did so to accomodate for some consumers of traverse() that expected
the starting vnode to stay as-is. But that introduced the leak in the
case when a mounted filesystem was found and its root vnode was
returned.
r299914 removed the troublesome consumers and now there is no reason to
keep the starting vnode. So, now the new rules are:
- if there is no mounted filesystem, then nothing is changed
- otherwise the starting vnode is always released
- the root vnode of the mounted filesystem is returned locked and
referenced in the case of success
MFC after: 5 weeks
X-MFC after: r299914
* Remove excessive references on a snapshot mountpoint vnode.
zfsctl_snapdir_lookup() called VN_HOLD() on a vnode returned from
zfsctl_snapshot_mknode() and the latter also had a call to VN_HOLD()
on the same vnode.
On top of that gfs_dir_create() already returns the vnode with the
use count of 1 (set in getnewvnode).
So there was 3 references on the vnode.
* mount_snapshot() should keep a reference to a covered vnode.
That reference is owned by the mountpoint (mounted snapshot filesystem).
* Remove cryptic manipulations of a covered vnode in zfs_umount().
FreeBSD dounmount() already does the right thing and releases the covered
vnode.
PR: 207464
Reported by: dustinwenz@ebureau.com
Tested by: Howard Powell <hpowell@lighthouseinstruments.com>
MFC after: 3 weeks
Previously several places were doing it on its own, partially
incorrectly (e.g. without the filedesc locked) or even actively harmful
by populating jdir or assigning rootvnode without vrefing it.
Reviewed by: kib
crash.sh script attached to FreeNAS bug 4109:
https://bugs.freenas.org/issues/4109
Three are in the snapshot layer:
a) AVG explains in his notes: https://wiki.freebsd.org/AvgVfsSolarisVsFreeBSD
"VOP_INACTIVE must not do any destructive actions to a vnode
and its filesystem node, nor invalidate them in any way."
gfs_vop_inactive and zfsctl_snapshot_inactive did just that. In
OpenSolaris VOP_INACTIVE is much closer to FreeBSD's VOP_RECLAIM.
Rename & move them to gfs_vop_reclaim and zfsctl_snapshot_reclaim
and merge in the requisite vnode_destroy from zfsctl_common_reclaim.
b) gfs_lookup_dot and various zfsctl functions do not honor the
FreeBSD VFS convention of only locking from the root downward. When
looking up ".." the convention is to drop the current leaf vnode lock before
acquiring the directory vnode and then subsequently re-acquiring the lock on the
leaf vnode. This fixes that in all the places that our exercised by crash.sh.
c) The snapshot may already be unmounted when the directory vnode is reclaimed.
Check for this case and return.
One in the common layer:
d) Callers of traverse expect the reference to the vnode passed in to be
maintained. Don't release it.
This last one may be an unclear contract. There may in fact be some callers that
do expect the reference to be dropped on success in addition to callers that
expect it to be released. In this case a further audit of the callers is needed
and a consensus on the correct behavior.
PR: 184677
Submitted by: kmacy
Reviewed by: delphij, will, avg
MFC after: 2 weeks
Sponsored by: iXsystems
Remove previously added kmem methods in favour of defines which
allow diff minimisation between upstream code base.
Rebalance ARC free target to be vm_pageout_wakeup_thresh by default
which eliminates issue where ARC gets minimised instead of balancing
with VM pageout. The restores the target point prior to r270759.
Bring in missing upstream only changes which move unused code to
further eliminate code differences.
Add additional DTRACE probe to aid monitoring of ARC behaviour.
Enable upstream i386 code paths on platforms which don't define
UMA_MD_SMALL_ALLOC.
Fix mixture of byte an page values in arc_memory_throttle i386 code
path value assignment of available_memory.
PR: 187594
Review: D702
Reviewed by: avg
MFC after: 1 week
X-MFC-With: r270759 & r270861
Sponsored by: Multiplay
Also restore kmem_used() check for i386 as it has KVA limits that the raw
page counts above don't consider
PR: 187594
Reviewed by: peter
X-MFC-With: r270759
Review: D700
Sponsored by: Multiplay
Prior to this change we triggered ARC reclaim when kmem usage passed 3/4
of the total available, as indicated by vmem_size(kmem_arena, VMEM_ALLOC).
This could lead large amounts of unused RAM e.g. on a 192GB machine with
ARC the only major RAM consumer, 40GB of RAM would remain unused.
The old method has also been seen to result in extreme RAM usage under
certain loads, causing poor performance and stalls.
We now trigger ARC reclaim when the number of free pages drops below the
value defined by the new sysctl vfs.zfs.arc_free_target, which defaults
to the value of vm.v_free_target.
Credit to Karl Denninger for the original patch on which this update was
based.
PR: 191510 and 187594
Tested by: dteske
MFC after: 1 week
Relnotes: yes
Sponsored by: Multiplay
These changes prevent sysctl(8) from returning proper output,
such as:
1) no output from sysctl(8)
2) erroneously returning ENOMEM with tools like truss(1)
or uname(1)
truss: can not get etype: Cannot allocate memory
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.
Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.
MFC after: 2 weeks
Sponsored by: Mellanox Technologies
To reduce the diff struct pcu.cnt field was not renamed, so
PCPU_OP(cnt.field) is still used. pc_cnt and pcpu are also used in
kvm(3) and vmstat(8). The goal was to not affect externally used KPI.
Bump __FreeBSD_version_ in case some out-of-tree module/code relies on the
the global cnt variable.
Exp-run revealed no ports using it directly.
No objection from: arch@
Sponsored by: EMC / Isilon Storage Division
943 zio_interrupt ends up calling taskq_dispatch with TQ_SLEEP
illumos/illumos-gate@5aeb94743e
Essentially FreeBSD taskqueues already operate in a mode that
was added to Illumos with taskq_dispatch_ent change.
We even exposed the superior FreeBSD interface as taskq_dispatch_safe.
Now we just rename taskq_dispatch_safe to taskq_dispatch_ent and
struct struct ostask to taskq_ent_t, so that code differences will be
minimal.
After this change sys/cddl/compat/opensolaris/sys/taskq.h header is no
longer needed.
Note that this commit is not an MFV because the upstream change was not
individually committed to the vendor area.
MFC after: 8 days
transparent layering and better fragmentation.
- Normalize functions that allocate memory to use kmem_*
- Those that allocate address space are named kva_*
- Those that operate on maps are named kmap_*
- Implement recursive allocation handling for kmem_arena in vmem.
Reviewed by: alc
Tested by: pho
Sponsored by: EMC / Isilon Storage Division
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
In particular, do not lock Giant conditionally when calling into the
filesystem module, remove the VFS_LOCK_GIANT() and related
macros. Stop handling buffers belonging to non-mpsafe filesystems.
The VFS_VERSION is bumped to indicate the interface change which does
not result in the interface signatures changes.
Conducted and reviewed by: attilio
Tested by: pho
User upgrades his system to fix the problem, but if he has any ZFS snapshots
for the file system which contains problematic binary, any user can mount the
snapshot and execute vulnerable binary.
Prevent this from happening by always mounting snapshots with setuid turned off.
MFC after: 2 weeks
The task structure might be no longer available.
This also allows to eliminates the need for two tasks in the zio structure.
Submitted by: anonymous
MFC after: 2 weeks
Few new things available from now on:
- Data deduplication.
- Triple parity RAIDZ (RAIDZ3).
- zfs diff.
- zpool split.
- Snapshot holds.
- zpool import -F. Allows to rewind corrupted pool to earlier
transaction group.
- Possibility to import pool in read-only mode.
MFC after: 1 month
with filesystems created under MacOS X ZFS port. This is kind of filesystem
corruption (we don't allow for setting empty ACLs), so make acl_get_file(3)
and related syscalls fail with EINVAL in that case. In theory, we could
return empty ACL to userland, but I'm afraid this would break some code.
MFC after: 3 days
physical memory
This is needed to correctly autotune ZFS ARC size when vm_kmem_size is
set to value larger than available physical memory.
MFC after: 2 weeks
- better ACL caching and speedup of ACL permission checks
- faster handling of stat()
- lowered mutex contention in the read/writer lock (rrwlock)
- several related bugfixes
Detailed information (OpenSolaris onnv changesets and Bug IDs):
9749:105f407a2680
6802734 Support for Access Based Enumeration (not used on FreeBSD)
6844861 inconsistent xattr readdir behavior with too-small buffer
9866:ddc5f1d8eb4e
6848431 zfs with rstchown=0 or file_chown_self privilege allows user to "take" ownership
9981:b4907297e740
6775100 stat() performance on files on zfs should be improved
6827779 rrwlock is overly protective of its counters
10143:d2d432dfe597
6857433 memory leaks found at: zfs_acl_alloc/zfs_acl_node_alloc
6860318 truncate() on zfsroot succeeds when file has a component of its path set without access permission
10232:f37b85f7e03e
6865875 zfs sometimes incorrectly giving search access to a dir
10250:b179ceb34b62
6867395 zpool_upgrade_007_pos testcase panic'd with BAD TRAP: type=e (#pf Page fault)
10269:2788675568fd
6868276 zfs_rezget() can be hazardous when znode has a cached ACL
10295:f7a18a1e9610
6870564 panic in zfs_getsecattr
Approved by: delphij (mentor)
Obtained from: OpenSolaris (multiple Bug IDs)
MFC after: 2 weeks
in Solaris 10 updates 141445-09 and 142901-14.
Detailed information:
(OpenSolaris revisions and Bug IDs, Solaris 10 patch numbers)
7844:effed23820ae
6755435 zfs_open() and zfs_close() needs to use ZFS_ENTER/ZFS_VERIFY_ZP (141445-01)
7897:e520d8258820
6748436 inconsistent zpool.cache in boot_archive could panic a zfs root filesystem upon boot-up (141445-01)
7965:b795da521357
6740164 zpool attach can create an illegal root pool (141909-02)
8084:b811cc60d650
6769612 zpool_import() will continue to write to cachefile even if altroot is set (N/A)
8121:7fd09d4ebd9c
6757430 want an option for zdb to disable space map loading and leak tracking (141445-01)
8129:e4f45a0bfbb0
6542860 ASSERT: reason != VDEV_LABEL_REMOVE||vdev_inuse(vd, crtxg, reason, 0) (141445-01)
8188:fd00c0a81e80
6761100 want zdb option to select older uberblocks (141445-01)
8190:6eeea43ced42
6774886 zfs_setattr() won't allow ndmp to restore SUNWattr_rw (141445-01)
8225:59a9961c2aeb
6737463 panic while trying to write out config file if root pool import fails (141445-01)
8227:f7d7be9b1f56
6765294 Refactor replay (141445-01)
8228:51e9ca9ee3a5
6572357 libzfs should do more to avoid mnttab lookups (141909-01)
6572376 zfs_iter_filesystems and zfs_iter_snapshots get objset stats twice (141909-01)
8241:5a60f16123ba
6328632 zpool offline is a bit too conservative (141445-01)
6739487 ASSERT: txg <= spa_final_txg due to scrub/export race (141445-01)
6767129 ASSERT: cvd->vdev_isspare, in spa_vdev_detach() (141445-01)
6747698 checksum failures after offline -t / export / import / scrub (141445-01)
6745863 ZFS writes to disk after it has been offlined (141445-01)
6722540 50% slowdown on scrub/resilver with certain vdev configurations (141445-01)
6759999 resilver logic rewrites ditto blocks on both source and destination (141445-01)
6758107 I/O should never suspend during spa_load() (141445-01)
6776548 codereview(1) runs off the page when faced with multi-line comments (N/A)
6761406 AMD errata 91 workaround doesn't work on 64-bit systems (141445-01)
8242:e46e4b2f0a03
6770866 GRUB/ZFS should require physical path or devid, but not both (141445-01)
8269:03a7e9050cfd
6674216 "zfs share" doesn't work, but "zfs set sharenfs=on" does (141445-01)
6621164 $SRC/cmd/zfs/zfs_main.c seems to have a syntax error in the translation note (141445-01)
6635482 i18n problems in libzfs_dataset.c and zfs_main.c (141445-01)
6595194 "zfs get" VALUE column is as wide as NAME (141445-01)
6722991 vdev_disk.c: error checking for ddi_pathname_to_dev_t() must test for NODEV (141445-01)
6396518 ASSERT strings shouldn't be pre-processed (141445-01)
8274:846b39508aff
6713916 scrub/resilver needlessly decompress data (141445-01)
8343:655db2375fed
6739553 libzfs_status msgid table is out of sync (141445-01)
6784104 libzfs unfairly rejects numerical values greater than 2^63 (141445-01)
6784108 zfs_realloc() should not free original memory on failure (141445-01)
8525:e0e0e525d0f8
6788830 set large value to reservation cause core dump (141445-01)
6791064 want sysevents for ZFS scrub (141445-01)
6791066 need to be able to set cachefile on faulted pools (141445-01)
6791071 zpool_do_import() should not enable datasets on faulted pools (141445-01)
6792134 getting multiple properties on a faulted pool leads to confusion (141445-01)
8547:bcc7b46e5ff7
6792884 Vista clients cannot access .zfs (141445-01)
8632:36ef517870a3
6798384 It can take a village to raise a zio (141445-01)
8636:7e4ce9158df3
6551866 deadlock between zfs_write(), zfs_freesp(), and zfs_putapage() (141909-01)
6504953 zfs_getpage() misunderstands VOP_GETPAGE() interface (141909-01)
6702206 ZFS read/writer lock contention throttles sendfile() benchmark (141445-01)
6780491 Zone on a ZFS filesystem has poor fork/exec performance (141445-01)
6747596 assertion failed: DVA_EQUAL(BP_IDENTITY(&zio->io_bp_orig), BP_IDENTITY(zio->io_bp))); (141445-01)
8692:692d4668b40d
6801507 ZFS read aggregation should not mind the gap (141445-01)
8697:e62d2612c14d
6633095 creating a filesystem with many properties set is slow (141445-01)
8768:dfecfdbb27ed
6775697 oracle crashes when overwriting after hitting quota on zfs (141909-01)
8811:f8deccf701cf
6790687 libzfs mnttab caching ignores external changes (141445-01)
6791101 memory leak from libzfs_mnttab_init (141445-01)
8845:91af0d9c0790
6800942 smb_session_create() incorrectly stores IP addresses (N/A)
6582163 Access Control List (ACL) for shares (141445-01)
6804954 smb_search - shortname field should be space padded following the NULL terminator (N/A)
6800184 Panic at smb_oplock_conflict+0x35() (N/A)
8876:59d2e67b4b65
6803822 Reboot after replacement of system disk in a ZFS mirror drops to grub> prompt (141445-01)
8924:5af812f84759
6789318 coredump when issue zdb -uuuu poolname/ (141445-01)
6790345 zdb -dddd -e poolname coredump (141445-01)
6797109 zdb: 'zdb -dddddd pool_name/fs_name inode' coredump if the file with inode was deleted (141445-01)
6797118 zdb: 'zdb -dddddd poolname inum' coredump if I miss the fs name (141445-01)
6803343 shareiscsi=on failed, iscsitgtd failed request to share (141445-01)
9030:243fd360d81f
6815893 hang mounting a dataset after booting into a new boot environment (141445-01)
9056:826e1858a846
6809691 'zpool create -f' no longer overwrites ufs infomation (141445-01)
9179:d8fbd96b79b3
6790064 zfs needs to determine uid and gid earlier in create process (141445-01)
9214:8d350e5d04aa
6604992 forced unmount + being in .zfs/snapshot/<snap1> = not happy (141909-01)
6810367 assertion failed: dvp->v_flag & VROOT, file: ../../common/fs/gfs.c, line: 426 (141909-01)
9229:e3f8b41e5db4
6807765 ztest_dsl_dataset_promote_busy needs to clean up after ENOSPC (141445-01)
9230:e4561e3eb1ef
6821169 offlining a device results in checksum errors (141445-01)
6821170 ZFS should not increment error stats for unavailable devices (141445-01)
6824006 need to increase issue and interrupt taskqs threads in zfs (141445-01)
9234:bffdc4fc05c4
6792139 recovering from a suspended pool needs some work (141445-01)
6794830 reboot command hangs on a failed zfs pool (141445-01)
9246:67c03c93c071
6824062 System panicked in zfs_mount due to NULL pointer dereference when running btts and svvs tests (141909-01)
9276:a8a7fc849933
6816124 System crash running zpool destroy on broken zpool (141445-03)
9355:09928982c591
6818183 zfs snapshot -r is slow due to set_snap_props() doing txg_wait_synced() for each new snapshot (141445-03)
9391:413d0661ef33
6710376 log device can show incorrect status when other parts of pool are degraded (141445-03)
9396:f41cf682d0d3 (part already merged)
6501037 want user/group quotas on ZFS (141445-03)
6827260 assertion failed in arc_read(): hdr == pbuf->b_hdr (141445-03)
6815592 panic: No such hold X on refcount Y from zfs_znode_move (141445-03)
6759986 zfs list shows temporary %clone when doing online zfs recv (141445-03)
9404:319573cd93f8
6774713 zfs ignores canmount=noauto when sharenfs property != off (141445-03)
9412:4aefd8704ce0
6717022 ZFS DMU needs zero-copy support (141445-03)
9425:e7ffacaec3a8
6799895 spa_add_spares() needs to be protected by config lock (141445-03)
6826466 want to post sysevents on hot spare activation (141445-03)
6826468 spa 'allowfaulted' needs some work (141445-03)
6826469 kernel support for storing vdev FRU information (141445-03)
6826470 skip posting checksum errors from DTL regions of leaf vdevs (141445-03)
6826471 I/O errors after device remove probe can confuse FMA (141445-03)
6826472 spares should enjoy some of the benefits of cache devices (141445-03)
9443:2a96d8478e95
6833711 gang leaders shouldn't have to be logical (141445-03)
9463:d0bd231c7518
6764124 want zdb to be able to checksum metadata blocks only (141445-03)
9465:8372081b8019
6830237 zfs panic in zfs_groupmember() (141445-03)
9466:1fdfd1fed9c4
6833162 phantom log device in zpool status (141445-03)
9469:4f68f041ddcd
6824968 add ZFS userquota support to rquotad (141445-03)
9470:6d827468d7b5
6834217 godfather I/O should reexecute (141445-03)
9480:fcff33da767f
6596237 Stop looking and start ganging (141909-02)
9493:9933d599bc93
6623978 lwb->lwb_buf != NULL, file ../../../uts/common/fs/zfs/zil.c, line 787, function zil_lwb_commit (141445-06)
9512:64cafcbcc337
6801810 Commit of aligned streaming rewrites to ZIL device causes unwanted disk reads (N/A)
9515:d3b739d9d043
6586537 async zio taskqs can block out userland commands (142901-09)
9554:787363635b6a
6836768 zfs_userspace() callback has no way to indicate failure (N/A)
9574:1eb6a6ab2c57
6838062 zfs panics when an error is encountered in space_map_load() (141909-02)
9583:b0696cd037cc
6794136 Panic BAD TRAP: type=e when importing degraded zraid pool. (141909-03)
9630:e25a03f552e0
6776104 "zfs import" deadlock between spa_unload() and spa_async_thread() (141445-06)
9653:a70048a304d1
6664765 Unable to remove files when using fat-zap and quota exceeded on ZFS filesystem (141445-06)
9688:127be1845343
6841321 zfs userspace / zfs get userused@ doesn't work on mounted snapshot (N/A)
6843069 zfs get userused@S-1-... doesn't work (N/A)
9873:8ddc892eca6e
6847229 assertion failed: refcount_count(&tx->tx_space_written) + delta <= tx->tx_space_towrite in dmu_tx.c (141445-06)
9904:d260bd3fd47c
6838344 kernel heap corruption detected on zil while stress testing (141445-06)
9951:a4895b3dd543
6844900 zfs_ioc_userspace_upgrade leaks (N/A)
10040:38b25aeeaf7a
6857012 zfs panics on zpool import (141445-06)
10000:241a51d8720c
6848242 zdb -e no longer works as expected (N/A)
10100:4a6965f6bef8
6856634 snv_117 not booting: zfs_parse_bootfs: error2 (141445-07)
10160:a45b03783d44
6861983 zfs should use new name <-> SID interfaces (N/A)
6862984 userquota commands can hang (141445-06)
10299:80845694147f
6696858 zfs receive of incremental replication stream can dereference NULL pointer and crash (N/A)
10302:a9e3d1987706
6696858 zfs receive of incremental replication stream can dereference NULL pointer and crash (fix lint) (N/A)
10575:2a8816c5173b (partial merge)
6882227 spa_async_remove() shouldn't do a full clear (142901-14)
10800:469478b180d9
6880764 fsync on zfs is broken if writes are greater than 32kb on a hard crash and no log attached (142901-09)
6793430 zdb -ivvvv assertion failure: bp->blk_cksum.zc_word[2] == dmu_objset_id(zilog->zl_os) (N/A)
10801:e0bf032e8673 (partial merge)
6822816 assertion failed: zap_remove_int(ds_next_clones_obj) returns ENOENT (142901-09)
10810:b6b161a6ae4a
6892298 buf->b_hdr->b_state != arc_anon, file: ../../common/fs/zfs/arc.c, line: 2849 (142901-09)
10890:499786962772
6807339 spurious checksum errors when replacing a vdev (142901-13)
11249:6c30f7dfc97b
6906110 bad trap panic in zil_replay_log_record (142901-13)
6906946 zfs replay isn't handling uid/gid correctly (142901-13)
11454:6e69bacc1a5a
6898245 suspended zpool should not cause rest of the zfs/zpool commands to hang (142901-10)
11546:42ea6be8961b (partial merge)
6833999 3-way deadlock in dsl_dataset_hold_ref() and dsl_sync_task_group_sync() (142901-09)
Discussed with: pjd
Approved by: delphij (mentor)
Obtained from: OpenSolaris (multiple Bug IDs)
MFC after: 2 months
This eliminates the only place where we can sleep when calling zio_interrupt().
As a side-effect this can actually improve performance a little as we
allocate one less thing for every I/O.
Prodded by: kib
MFC after: 1 week
- Properly initialize and destroy system_taskq.
- Add a dummy implementation of taskq_create_proc().
Note: We do not currently use system_taskq in ZFS so this is mostly a
no-op at this time. Proper system_taskq initialization is required
by newer ZFS code.
Ok'ed by: pjd
MFC after: 2 weeks
