Commit Graph

1328 Commits

Author SHA1 Message Date
Mariusz Zaborski
347a39b4a6 Add support for the arrays in nvlist library.
- Add
  nvlist_{add,get,take,move,exists,free}_{number,bool,string,nvlist,
  descriptor} functions.
- Add support for (un)packing arrays.
- Add the nvl_array_next field to the nvlist structure.
  If an array is added by the nvlist_{move,add}_nvlist_array function
  this field will contains next element in the array.
- Add the nitems field to the nvpair and nvpair_header structure.
  This field contains number of elements in the array.
- Add special flag (NV_FLAG_IN_ARRAY) which is set if nvlist is a part of
  an array.
- Add special type (NV_TYPE_NVLIST_ARRAY_NEXT).This type is used only
  on packing/unpacking.
- Add new API for traversing arrays (nvlist_get_array_next).
- Add the nvlist_get_pararr function which combines the
  nvlist_get_array_next and nvlist_get_parent functions. If nvlist is in
  the array it will return next element from array. If nvlist is last
  element in array or it isn't in array it will return his
  container (parent). This function should simplify traveling over nvlist.
- Add tests for new features.
- Add documentation for new functions.
- Add my copyright.
- Regenerate the sys/cddl/compat/opensolaris/sys/nvpair.h file.

PR:		191083
Reviewed by:	allanjude (doc)
Approved by:	pjd (mentor)
2015-08-15 06:34:49 +00:00
Alexander Motin
d8928f479b Remove some random accumulated diff from Illumos.
Submitted by:	avg (partially)
2015-08-14 13:43:12 +00:00
Alexander Motin
6cb8dbf791 2618 arc.c mistypes in the comments
Reviewed by: Jason King <jason.brian.king@gmail.com>
Reviewed by: Josef Sipek <jeffpc@josefsipek.net>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Bart Coddens <bart.coddens@gmail.com>

illumos/illumos-gate@fc98fea58e
2015-08-14 13:10:30 +00:00
Alexander Motin
997d864ce0 Fix r286766 build with debug. 2015-08-14 11:47:53 +00:00
Alexander Motin
ab4d08c3d3 Fix minor mismerge sometimes earlier. 2015-08-14 09:48:23 +00:00
Alexander Motin
5ba12a280a MFV r286765: 5817 change type of arcs_size from uint64_t to refcount_t
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Paul Dagnelie <paul.dagnelie@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: Prakash Surya <prakash.surya@delphix.com>

illumos/illumos-gate@2fd872a734

As a way to make it more difficult to introduce bugs into the ARC, and to
make it easier to diagnose issues when bugs do creep in, it would be
beneficial to change the type of the arc_state_t's arcs_size field to be
a refcount_t instead of a uint64_t. This would allow us to make stricter
checks when incrementing and decrementing the value with debugging enabled,
but still fallback to simple, fast atomic operations when debugging is
disabled.
2015-08-14 09:39:23 +00:00
Alexander Motin
ab4930d98c MFV r285025: 6033 arc_adjust() should search MFU lists for oldest buffer
when adjusting MFU size.

illumos/illumos-gate@31c46cf23c

https://www.illumos.org/issues/6033
  When we're looking for the list containing oldest buffer we never
  actually look at the MFU lists even when we try to evict from MFU.
  looks like a copy paste error, the fix is here:

Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Reviewed by: Xin Li <delphij@delphij.net>
Reviewed by: Prakash Surya <me@prakashsurya.com>
Approved by: Matthew Ahrens <mahrens@delphix.com>
Author: Alek Pinchuk <alek@nexenta.com>
Obtained from:  illumos
2015-08-14 09:33:46 +00:00
Alexander Motin
e0360e14d2 MFV r277431: 5497 lock contention on arcs_mtx
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Prakash Surya <prakash.surya@delphix.com>

illumos/illumos-gate@244781f10d

This patch attempts to reduce lock contention on the current arc_state_t
mutexes. These mutexes are used liberally to protect the number of LRU
lists within the ARC (e.g. ARC_mru, ARC_mfu, etc). The granularity at
which these locks are acquired has been shown to greatly affect the
performance of highly concurrent, cached workloads.
2015-08-14 09:31:07 +00:00
Alexander Motin
267b62ec43 Revert part of r205231, introducing multiple ARC state locks.
This local implementation will be replaced by one from Illumos to reduce
code divergence and make further merges easier.
2015-08-14 09:25:54 +00:00
Alexander Motin
49114ce463 MFV 286711: 6096 ZFS_SMB_ACL_RENAME needs to cleanup better
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Gordon Ross <gordon.w.ross@gmail.com>
Reviewed by: George Wilson <gwilson@zfsmail.com>
Approved by: Robert Mustacchi <rm@joyent.com>

illumos/illumos-gate@8f5190a540
2015-08-13 00:13:55 +00:00
Alexander Motin
3b1f51e911 MFV 286709:
6093 zfsctl_shares_lookup should only VN_RELE() on zfs_zget() success

Reviewed by: Gordon Ross <gwr@nexenta.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Dan McDonald <danmcd@omniti.com>

illumos/illumos-gate@0f92170f1e
2015-08-13 00:10:36 +00:00
Alexander Motin
0d0def87fe MFV 286707: 5959 clean up per-dataset feature count code
Reviewed by: Toomas Soome <tsoome@me.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Alex Reece <alex@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Matthew Ahrens <mahrens@delphix.com>

illumos/illumos-gate@ca0cc3918a

A ZFS feature flags (large blocks) tracks its refcounts as the number of
datasets that have ever used the feature. Several features of this type
are planned to be added (new checksum functions). This code should be made
common infrastructure rather than duplicating the code for each feature.
2015-08-12 23:59:17 +00:00
Alexander Motin
b696497df0 MFV r286704: 5960 zfs recv should prefetch indirect blocks
5925 zfs receive -o origin=

Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Author: Paul Dagnelie <pcd@delphix.com>

While running 'zfs recv' we noticed that every 128th 8K block required a
read. We were seeing that restore_write() was calling dmu_tx_hold_write()
and the indirect block was not cached. We should prefetch upcoming indirect
blocks to avoid having to go to disk and blocking the restore_write().

Allow an incremental send stream to be received as a clone, even if the
stream does not mark it as a clone.
2015-08-12 22:41:06 +00:00
Alexander Motin
d0687a01d7 MFV r284763: 5981 Deadlock in dmu_objset_find_dp
illumos/illumos-gate@1d3f896f54

https://www.illumos.org/issues/5981
  When dmu_objset_find_dp gets called with a read lock held, it fans out
  the work to the task queue. Each task in turn acquires its own read
  lock before calling the callback. If during this process anyone tries
  to a acquire a write lock, it will stall all read lock requests.Thus
  the tasks will never finish, the read lock of the caller will never
  get freed and the write lock never acquired.  deadlock.

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Arne Jansen <jansen@webgods.de>
2015-08-12 19:10:29 +00:00
Alexander Motin
101a6d4eac MFV r284762: 5269 zpool import slow
illumos/illumos-gate@12380e1e70

https://www.illumos.org/issues/5269
  When importing a pool (at boot or with zpool import) with many
  filesystem, the process can take minutes. It doesn't matter whether
  the pool has been exported cleanly or uncleanly.  The problem is that
  each dataset has its own log chain. On import, all datasets have to be
  checked if there are logs to replay.  The idea is to speed up this
  process by paralellizing it.

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Arne Jansen <jansen@webgods.de>
2015-08-12 18:47:30 +00:00
Alexander Motin
ebf527de10 MFV r286682: 5765 add support for estimating send stream size with
lzc_send_space when source is a bookmark

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Steven Hartland <killing@multiplay.co.uk>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Albert Lee <trisk@nexenta.com>
Author: Max Grossman <max.grossman@delphix.com>

illumos/illumos-gate@643da460c8
2015-08-12 18:23:08 +00:00
Alexander Motin
2d41b1006f MFV r286224: 5695 dmu_sync'ed holes do not retain birth time
illumos/illumos-gate@70163ac57e

https://www.illumos.org/issues/5695
  In dmu_sync_ready(), a hole block pointer will have it's logical size
  explicitly set as it's necessary for replay purposes. To "undo" this,
  dmu_sync_done() will zero out any hole that it finds. This becomes a
  problem when using the "hole_birth" feature, as this will also wipe out
  any birth time that might have happened to be set on the hole.
  ...
  As a fix, the logic to zero out a hole is only applied to old style
  holes with a birth time of zero. Holes created with the "hole_birth"
  feature enabled will have a non-zero birth time, and will be skipped
  (thus preserving the ltime, type, and level information as well).
  In addition, zdb was updated to also print the ltime, type, and level
  information for these new style holes. Previously, only the logical
  birth time would be printed.

Author: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Dan McDonald <danmcd@omniti.com>
2015-08-12 17:21:41 +00:00
Alexander Motin
ef00c83db1 Fix set of sign extension bugs in r286625. 2015-08-12 08:36:58 +00:00
Alexander Motin
b3fc966389 Fix assertion panic caused by combination of r286598 and TRIM. 2015-08-11 19:15:55 +00:00
Alexander Motin
3caed89878 Fix r286625 build on i386. 2015-08-11 12:38:01 +00:00
Alexander Motin
a3b3a9752c Fix minor mismerge in r286574. 2015-08-11 12:22:16 +00:00
Alexander Motin
c350858a50 MFV r277425:
5376 arc_kmem_reap_now() should not result in clearing arc_no_grow
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Steven Hartland <killing@multiplay.co.uk>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Matthew Ahrens <mahrens@delphix.com>

illumos/illumos-gate@2ec99e3e98
2015-08-11 10:39:19 +00:00
Alexander Motin
6be7d38913 Remove extra lock, that IMO only creates potential problems now. 2015-08-11 09:18:51 +00:00
Alexander Motin
1af86496cb MFV 286604: 5812 assertion failed in zrl_tryenter(): zr_owner==NULL
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: Will Andrews <will@freebsd.org>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Matthew Ahrens <mahrens@delphix.com>

illumos/illumos-gate@8df173054c
2015-08-10 21:36:51 +00:00
Alexander Motin
799f47828d MFV 286602: 5810 zdb should print details of bpobj
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Will Andrews <will@freebsd.org>
Reviewed by: Simon Klinkert <simon.klinkert@gmail.com>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Matthew Ahrens <mahrens@delphix.com>

illumos/illumos-gate@732885fca0
2015-08-10 21:32:40 +00:00
Alexander Motin
c70c15ffa9 MFV 286599: 5808 spa_check_logs is not necessary on readonly pools
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Paul Dagnelie <paul.dagnelie@delphix.com>
Reviewed by: Simon Klinkert <simon.klinkert@gmail.com>
Reviewed by: Will Andrews <will@freebsd.org>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Matthew Ahrens <mahrens@delphix.com>

illumos/illumos-gate@23367a2f2c
2015-08-10 21:19:42 +00:00
Alexander Motin
f7bf11ab59 MFV 286597: 5701 zpool list reports incorrect "alloc" value for cache devices
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Alek Pinchuk <alek.pinchuk@nexenta.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Prakash Surya <prakash.surya@delphix.com>

illumos/illumos-gate@a52fc310ba
2015-08-10 21:13:59 +00:00
Alexander Motin
2e92f38b63 Local addition and mismerge fix for r286579. 2015-08-10 20:34:46 +00:00
Alexander Motin
de8b7ceff1 MFV 286588: 5820 verify failed in zio_done(): BP_EQUAL(bp, io_bp_orig)
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Steven Hartland <killing@multiplay.co.uk>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: Matthew Ahrens <mahrens@delphix.com>

illumod/illumos-gate@34e8acef00
2015-08-10 19:38:07 +00:00
Alexander Motin
57f7c5acf5 MFV 286586: 5746 more checksumming in zfs send
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Albert Lee <trisk@omniti.com>
Author: Matthew Ahrens <mahrens@delphix.com>

illumos/illumos-gate@98110f08fa
2015-08-10 19:32:58 +00:00
Alexander Motin
9b4b955150 MFV r277430: 5313 Allow I/Os to be aggregated across ZIO priority classes
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Reviewed by: Will Andrews <willa@SpectraLogic.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Justin T. Gibbs <justing@spectralogic.com>

illumos/illumos-gate@fe319232d2
2015-08-10 12:39:10 +00:00
Alexander Motin
498b9d6c63 Fix r286574 build in user-space. 2015-08-10 12:25:26 +00:00
Alexander Motin
0702ce1a52 Fix r286570 build with debug. 2015-08-10 11:52:54 +00:00
Alexander Motin
83a6947e11 MFV r277428: 5056 ZFS deadlock on db_mtx and dn_holds
Reviewed by: Will Andrews <willa@spectralogic.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Justin Gibbs <justing@spectralogic.com>

illumos/illumos-gate@bc9014e6a8
2015-08-10 11:30:07 +00:00
Alexander Motin
f13e9e1470 MFV r277427: 5445 Add more visibility via arcstats; specifically
arc_state_t stats and differentiate between "data" and "metadata"

Reviewed by: Basil Crow <basil.crow@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Bayard Bell <bayard.bell@nexenta.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Prakash Surya <prakash.surya@delphix.com>

illumos/illumos-gate@4076b1bf41
2015-08-10 10:59:58 +00:00
Alexander Motin
c908dc6f4b MFV r277426: 5408 managing ZFS cache devices requires lots of RAM
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Don Brady <dev.fs.zfs@gmail.com>
Reviewed by: Josef 'Jeff' Sipek <josef.sipek@nexenta.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: Chris Williamson <Chris.Williamson@delphix.com>

illumos/illumos-gate@89c86e3229

Currently, every buffer cached in the L2ARC is accompanied by a 240-byte
header in memory, leading to very high memory consumption when using very
large cache devices. These changes significantly reduce this overhead.

Currently:

L1-only header = 176 bytes
L1 + L2 or L2-only header = 176 bytes + 32 byte checksum + 32 byte l2hdr
    = 240 bytes

Memory-optimized:

L1-only header = 176 bytes
L1 + L2 header = 176 bytes + 32 byte checksum = 208 bytes
L2-only header = 96 bytes + 32 byte checksum = 128 bytes

So overall:

          Trunk  Optimized
        +-----------------+
L1-only | 176 B  | 176 B  | (same)
        +-----------------+
L1 & L2 | 240 B  | 208 B  | (saved 32 bytes)
        +-----------------+
L2-only | 240 B  | 128 B  | (saved 116 bytes)
        +-----------------+

For an average blocksize of 8KB, this means that for the L2ARC, the ratio
of metadata to data has gone down from about 2.92% to 1.56%.  For a
'storage optimized' EC2 instance with 1600GB of SSD and 60GB of RAM, this
means that we expect a completely full L2ARC to use (1600 GB * 0.0156) /
60GB = 41% of the available memory, down from 78%.
2015-08-10 10:34:23 +00:00
Alexander Motin
1838fc920f MFV 286555: Avoid 128K kmem allocations in mzap_upgrade()
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Steven Hartland <killing@multiplay.co.uk>
Approved by: Rich Lowe <richlowe@richlowe.net>

illumos/illumos-gate@be3e2ab906
2015-08-09 20:41:44 +00:00
Alexander Motin
475e2caa3d MFV 286553: 5769 Cast 'zfs bad bloc' to ULL for x86
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Paul Dagnelie <paul.dagnelie@delphix.com>
Reviewed by: Richard PALO <richard@NetBSD.org>
Approved by: Dan McDonald <danmcd@omniti.com>

illumos/illumos-gate@8c76e0763b
2015-08-09 20:32:30 +00:00
Alexander Motin
a5a2e782be MFV 286550: 5694 traverse_prefetcher does not prefetch enough
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Josef 'Jeff' Sipek <josef.sipek@nexenta.com>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: George Wilson <george.wilson@delphix.com>

illumos/illumos-gate@34d7ce052c
2015-08-09 20:23:35 +00:00
Alexander Motin
927211755b MFV 286548:
5693 ztest fails in dbuf_verify: buf[i] == 0, due to dedup and bp_override

Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Matthew Ahrens <mahrens@delphix.com>

illumos/illumos-gate@7f7ace3700
2015-08-09 20:08:38 +00:00
Alexander Motin
4ff9527edc MFV 286546:
5661 ZFS: "compression = on" should use lz4 if feature is enabled

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Reviewed by: Xin LI <delphij@freebsd.org>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Justin T. Gibbs <justing@spectralogic.com>

illumos/illumos-gate@db1741f555
2015-08-09 20:02:16 +00:00
Alexander Motin
9834135947 MFV 286544:
5630 stale bonus buffer in recycled dnode_t leads to data corruption

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Will Andrews <will@freebsd.org>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Justin T. Gibbs <justing@spectralogic.com>
2015-08-09 19:35:39 +00:00
Alexander Motin
07470009be MFV 286542: 5592 NULL pointer dereference in dsl_prop_notify_all_cb()
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Will Andrews <will@freebsd.org>
Approved by: Robert Mustacchi <rm@joyent.com>

illumos/illumos-gate@9d47dec048
2015-08-09 19:29:10 +00:00
Alexander Motin
1d367fea94 MFV 286540: 5531 NULL pointer dereference in dsl_prop_get_ds()
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Justin T. Gibbs <justing@spectralogic.com>

illumos/illumos-gate@e57a022b8f
2015-08-09 19:26:21 +00:00
Alexander Motin
c44a37d0b7 MFV 286538:
5562 ZFS sa_handle's violate kmem invariants, debug kernels panic on boot

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Robert Mustacchi <rm@fingolfin.org>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Rich Lowe <richlowe@richlowe.net>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Justin T. Gibbs <justing@spectralogic.com>

illumos/illumos-gate@0fda3cc5c1
2015-08-09 19:17:59 +00:00
Mark Johnston
1c9a705223 Remove a couple of unused fields from the FBT probe struct. 2015-08-03 17:39:36 +00:00
Steven Hartland
ebbc56ecd6 Fix KSTACK_PAGES check in ZFS module
The check introduced by r285946 failed to add the dependency on
opt_kstack_pages.h which meant the default value for the platform instead
of the customised options KSTACK_PAGES=X was being tested.

Also wrap in #ifdef __FreeBSD__ for portability.

MFC after:	3 days
Sponsored by:	Multiplay
2015-08-03 09:34:09 +00:00
Mark Johnston
48fcd357c4 Avoid dereferencing curthread->td_proc->p_cred in DTrace probe context.
When a process is exiting, there is a narrow window where p_cred may be
NULL while its threads are still executing. Specifically, the last thread
to exit a process sets the process state to PRS_ZOMBIE with the proc
spinlock held and then calls thread_exit(). thread_exit() drops the spin
lock, permitting the process to be reaped and thus causing its cred struct
to be released. However, the exiting thread may still cause DTrace probes
to fire by calling sched_throw(), resulting in a double fault if such a
probe enabling attempts to access the GID or UID DIF variables.

The thread's cred reference is not susceptible to this race since it is not
released until after the thread has exited.

MFC after:	1 week
2015-08-02 00:11:56 +00:00
Steven Hartland
1635369e99 Add warning about low KSTACK_PAGES for ZFS use
As ZFS requires a more kernel stack pages than is the default on some
architectures e.g. i386, warn if KSTACK_PAGES is less than
ZFS_MIN_KSTACK_PAGES (which is 4 at the time of writing).

MFC after:	3 days
Sponsored by:	Multiplay
2015-07-28 11:19:38 +00:00
Mark Johnston
d258fd1d98 Remove checks for a NULL return value from M_WAITOK allocations. 2015-07-21 23:44:36 +00:00