Commit Graph

348 Commits

Author SHA1 Message Date
Brian Behlendorf
4f34bd9792 Add taskq_wait_outstanding() function
SPL commit behlendorf/spl@9cef1b5 adds the taskq_wait_outstanding()
interface.  See the commit log for the full justification for this
addition.  This patch adds the required user space counterpart.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
2015-06-11 10:27:25 -07:00
Prakash Surya
ca0bf58d65 Illumos 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>

Porting notes and other significant code changes:

The illumos 5368 patch (ARC should cache more metadata), which
was never picked up by ZoL, is mostly reverted by this patch.

Since ZoL relies on the kernel asynchronously calling the shrinker to
actually reap memory, the shrinker wakes up arc_reclaim_waiters_cv every
time it runs.

The arc_adapt_thread() function no longer calls arc_do_user_evicts()
since the newly-added arc_user_evicts_thread() calls it periodically.

Notable conflicting ZoL commits which conflicted with this patch or
whose effects are either duplicated or un-done by this patch:

    302f753 - Integrate ARC more tightly with Linux
    39e055c - Adjust arc_p based on "bytes" in arc_shrink
    f521ce1 - Allow "arc_p" to drop to zero or grow to "arc_c"
    77765b5 - Remove "arc_meta_used" from arc_adjust calculation
    94520ca - Prune metadata from ghost lists in arc_adjust_meta

Trace support for multilist_insert() and multilist_remove() has been
added and produces the following output:

    fio-12498 [077] .... 112936.448324: zfs_multilist__insert: ml { offset 240 numsublists 80 sublistidx 63 }
    fio-12498 [077] .... 112936.448347: zfs_multilist__remove: ml { offset 240 numsublists 80 sublistidx 29 }

The following arcstats have been removed:

    recycle_miss - Used by arcstat.py and arc_summary.py, both of which
    have been updated appropriately.

    l2_writes_hdr_miss

The following arcstats have been added:

    evict_not_enough - Number of times arc_evict_state() was unable to
    evict enough buffers to reach its target amount.

    evict_l2_skip - Number of times arc_evict_hdr() skipped eviction
    because it was being written to the l2arc.

    l2_writes_lock_retry - Replaces l2_writes_hdr_miss.  Number of times
    l2arc_write_done() failed to acquire hash_lock (and re-tries).

    arc_meta_min - Shows the value of the zfs_arc_meta_min module
    parameter (see below).

The "index" column of the "dbuf" kstat has been removed since it doesn't
have a direct analog in the new multilist scheme.  Additional multilist-
related stats could be added in the future but would likely require
extensions to the mulilist API.

The following module parameters have been added:

    zfs_arc_evict_batch_limit - Number of ARC headers to free per sub-list
    before moving on to the next sub-list.

    zfs_arc_meta_min - Enforce a floor on the amount of metadata in
    the ARC.

    zfs_arc_num_sublists_per_state - Number of multilist sub-lists per
    ARC state.

    zfs_arc_overflow_shift - Controls amount by which the ARC must exceed
    the target size to be considered "overflowing".

Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov
2015-06-11 10:27:25 -07:00
Chris Williamson
b9541d6b7d Illumos 5408 - managing ZFS cache devices requires lots of RAM
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>

Porting notes:

Due to the restructuring of the ARC-related structures, this
patch conflicts with at least the following existing ZoL commits:

    6e1d7276c9
    Fix inaccurate arcstat_l2_hdr_size calculations

        The ARC_SPACE_HDRS constant no longer exists and has been
        somewhat equivalently replaced by HDR_L2ONLY_SIZE.

    e0b0ca983d
    Add visibility in to cached dbufs

        The new layering of l{1,2}arc_buf_hdr_t within the arc_buf_hdr
        struct requires additional structure member names to be used
        when referencing the inner items.  Also, the presence of L1 or L2
        inner member is indicated by flags using the new HDR_HAS_L{1,2}HDR
        macros.

Ported by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-06-11 10:27:25 -07:00
George Wilson
2a4324141f Illumos 5369 - arc flags should be an enum
5369 arc flags should be an enum
5370 consistent arc_buf_hdr_t naming scheme
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Alex Reece <alex.reece@delphix.com>
Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Approved by: Richard Lowe <richlowe@richlowe.net>

Porting notes:

ZoL has moved some ARC definitions into arc_impl.h.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Ported by: Tim Chase <tim@chase2k.com>
2015-06-11 10:27:25 -07:00
Matthew Ahrens
c3520e7f1f Illumos 5818 - zfs {ref}compressratio is incorrect with 4k sector size
5818 zfs {ref}compressratio is incorrect with 4k sector size
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Reviewed by: Steven Hartland <killing@multiplay.co.uk>
Approved by: Albert Lee <trisk@omniti.com>

References:
  https://www.illumos.org/issues/5818
  https://github.com/illumos/illumos-gate/commit/81cd5c5

Ported-by: Don Brady <don.brady@intel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3432
2015-06-10 16:24:01 -07:00
Arne Jansen
9c43027b3f Illumos 5269 - zpool import slow
5269 zpool import slow
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>

References:
  https://www.illumos.org/issues/5269
  https://github.com/illumos/illumos-gate/commit/12380e1e

Ported-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3396
2015-06-09 13:48:02 -07:00
Turbo Fredriksson
d050c627b5 Improve on the ZFS events documentation
* Add information about the 'zpool events' command in zpool(8).
* More events and payloads defined in zfs-events(5).
* I/O Stages and I/O Flags sections added.
* Remove unused legacy "zio_deadline" payload define.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3467
2015-06-09 11:19:19 -07:00
Brian Behlendorf
65037d9b25 Add libzfs_error_init() function
All fprintf() error messages are moved out of the libzfs_init()
library function where they never belonged in the first place.  A
libzfs_error_init() function is added to provide useful error
messages for the most common causes of failure.

Additionally, in libzfs_run_process() the 'rc' variable was renamed
to 'error' for consistency with the rest of the code base.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-05-22 13:34:58 -07:00
Tim Chase
f467b05a26 Initialize dbu_tqent in dmu_buf_init_user()
The dbu_evict_taskq added in 0c66c32d is only invoked via
taskq_dispatch_ent(). In these cases, ZoL's implementation of taskqs
requires the entries to be initialized first with taskq_init_ent() in
order that, among other things, the embedded spinlock is initialized
properly.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3419
2015-05-18 11:39:14 -07:00
Max Grossman
5dc8b7365f Illumos 5765 - add support for estimating send stream size with lzc_send_space when source is a bookmark
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>

References:
  https://www.illumos.org/issues/5765
  https://github.com/illumos/illumos-gate/commit/643da460

Porting notes:
* Unused variable 'recordsize' in dmu_send_estimate() dropped

Ported-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3397
2015-05-13 09:03:59 -07:00
Matthew Ahrens
252e1a54ab Illumos 5810 - zdb should print details of bpobj
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>

References:
  https://www.illumos.org/issues/5810
  https://github.com/illumos/illumos-gate/commit/732885fc

Ported-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3387
2015-05-11 15:10:24 -07:00
Tim Chase
e48533383b Linux 2.6.36 compat, use REQ_FAILFAST_MASK and remove pre-2.6.36 support
Commit f4af6bb783 which added support
for REQ_FAILFAST_MASK but the new autoconf test didn't use the same
preprocessor macro name as the code did.

The effect is that FAILFAST mode has not been enabled for ZoL in any
post-2.6.35 kernel.

Retire the HAVE_BIO_RW_FAILFAST interface used in pre-2.6.28 kernels.

Raise an error condition if the FAILFAST interface can't be detected.

Signed-off-by: Tim Chase <tim@onlight.com
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3386
2015-05-11 15:07:00 -07:00
Matthew Ahrens
f1512ee61e Illumos 5027 - zfs large block support
5027 zfs large block support
Reviewed by: Alek Pinchuk <pinchuk.alek@gmail.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Josef 'Jeff' Sipek <josef.sipek@nexenta.com>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Reviewed by: Saso Kiselkov <skiselkov.ml@gmail.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/5027
  https://github.com/illumos/illumos-gate/commit/b515258

Porting Notes:

* Included in this patch is a tiny ISP2() cleanup in zio_init() from
Illumos 5255.

* Unlike the upstream Illumos commit this patch does not impose an
arbitrary 128K block size limit on volumes.  Volumes, like filesystems,
are limited by the zfs_max_recordsize=1M module option.

* By default the maximum record size is limited to 1M by the module
option zfs_max_recordsize.  This value may be safely increased up to
16M which is the largest block size supported by the on-disk format.
At the moment, 1M blocks clearly offer a significant performance
improvement but the benefits of going beyond this for the majority
of workloads are less clear.

* The illumos version of this patch increased DMU_MAX_ACCESS to 32M.
This was determined not to be large enough when using 16M blocks
because the zfs_make_xattrdir() function will fail (EFBIG) when
assigning a TX.  This was immediately observed under Linux because
all newly created files must have a security xattr created and
that was failing.  Therefore, we've set DMU_MAX_ACCESS to 64M.

* On 32-bit platforms a hard limit of 1M is set for blocks due
to the limited virtual address space.  We should be able to relax
this one the ABD patches are merged.

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #354
2015-05-11 12:23:16 -07:00
Matthew Ahrens
63e3a8616b Illumos 5349 - verify that block pointer is plausible before reading
5349 verify that block pointer is plausible before reading
Reviewed by: Alex Reece <alex.reece@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Reviewed by: Xin Li <delphij@FreeBSD.org>
Reviewed by: Josef 'Jeff' Sipek <josef.sipek@nexenta.com>
Approved by: Gordon Ross <gwr@nexenta.com>

References:
  https://www.illumos.org/issues/5349
  https://github.com/illumos/illumos-gate/commit/f63ab3d5

Porting notes:
* Several variable declarations were moved due to C style needs

Ported-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3373
2015-05-08 14:09:15 -07:00
Christopher Siden
0c60cc326b Illumos 4951 - ZFS administrative commands (fix)
4951 ZFS administrative commands should use reserved space, not fail with ENOSPC
Approved by: Christopher Siden <christopher.siden@delphix.com>

References:
  https://www.illumos.org/issues/4951
  https://github.com/illumos/illumos-gate/commit/c39f2c8

Ported by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-05-04 09:41:10 -07:00
Matthew Ahrens
3d45fdd6c0 Illumos 4951 - ZFS administrative commands should use reserved space
4951 ZFS administrative commands should use reserved space, not with ENOSPC
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Garrett D'Amore <garrett@damore.org>

References:
  https://www.illumos.org/issues/4373
  https://github.com/illumos/illumos-gate/commit/7d46dc6

Ported by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-05-04 09:41:10 -07:00
Matthew Ahrens
83017311e4 Illumos 3654,3656
3654 zdb should print number of ganged blocks
3656 remove unused function zap_cursor_move_to_key()
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Dan McDonald <danmcd@nexenta.com>
Approved by: Garrett D'Amore <garrett@damore.org>

References:
  https://www.illumos.org/issues/3654
  https://www.illumos.org/issues/3656
  https://github.com/illumos/illumos-gate/commit/d5ee8a1

Porting Notes:

3655 and 3657 were part of this commit but those hunks were dropped
since they apply to mdb.

Ported by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-05-04 09:41:09 -07:00
George Wilson
98b254188a Illumos #5244 - zio pipeline callers should explicitly invoke next stage
5244 zio pipeline callers should explicitly invoke next stage
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Alex Reece <alex.reece@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Richard Elling <richard.elling@gmail.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: Steven Hartland <killing@multiplay.co.uk>
Approved by: Gordon Ross <gwr@nexenta.com>

References:
  https://www.illumos.org/issues/5244
  https://github.com/illumos/illumos-gate/commit/738f37b

Porting Notes:

1. The unported "2932 support crash dumps to raidz, etc. pools"
   caused a merge conflict due to a copyright difference in
   module/zfs/vdev_raidz.c.
2. The unported "4128 disks in zpools never go away when pulled"
   and additional Linux-specific changes caused merge conflicts in
   module/zfs/vdev_disk.c.

Ported-by: Richard Yao <richard.yao@clusterhq.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2828
2015-04-30 15:07:47 -07:00
Justin T. Gibbs
6ebebaceb1 Illumos 5531 - NULL pointer dereference in dsl_prop_get_ds()
5531 NULL pointer dereference in dsl_prop_get_ds()
Author: Justin T. Gibbs <justing@spectralogic.com>
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>

References:
  https://www.illumos.org/issues/5531
  https://github.com/illumos/illumos-gate/commit/e57a022

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-04-28 16:25:44 -07:00
Justin T. Gibbs
0c66c32d1d Illumos 5056 - ZFS deadlock on db_mtx and dn_holds
5056 ZFS deadlock on db_mtx and dn_holds
Author: Justin Gibbs <justing@spectralogic.com>
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>

References:
  https://www.illumos.org/issues/5056
  https://github.com/illumos/illumos-gate/commit/bc9014e

Porting Notes:

sa_handle_get_from_db():
  - the original patch includes an otherwise unmentioned fix for a
    possible usage of an uninitialised variable

dmu_objset_open_impl():
  - Under Illumos list_link_init() is the same as filling a list_node_t
    with NULLs, so they don't notice if they miss doing list_link_init()
    on a zero'd containing structure (e.g. allocated with kmem_zalloc as
    here). Under Linux, not so much: an uninitialised list_node_t goes
    "Boom!" some time later when it's used or destroyed.

dmu_objset_evict_dbufs():
  - reduce stack usage using kmem_alloc()

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-04-28 16:25:34 -07:00
Justin T. Gibbs
d683ddbb72 Illumos 5314 - Remove "dbuf phys" db->db_data pointer aliases in ZFS
5314 Remove "dbuf phys" db->db_data pointer aliases in ZFS
Author: Justin T. Gibbs <justing@spectralogic.com>
Reviewed by: Andriy Gapon <avg@freebsd.org>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Will Andrews <willa@spectralogic.com>
Approved by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/5314
  https://github.com/illumos/illumos-gate/commit/c137962

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-04-28 16:25:20 -07:00
Alex Reece
9925c28cde Illumos 5095 - panic when adding a duplicate dbuf to dn_dbufs
5095 panic when adding a duplicate dbuf to dn_dbufs
Author: Alex Reece <alex@delphix.com>
Reviewed by: Adam Leventhal <adam.leventhal@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Mattew Ahrens <mahrens@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: Josef Sipek <jeffpc@josefsipek.net>
Approved by: Robert Mustacchi <rm@joyent.com>

References:
  https://www.illumos.org/issues/5095
  https://github.com/illumos/illumos-gate/commit/86bb58a

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-04-28 16:24:49 -07:00
Justin T. Gibbs
5aea3644d6 Illumos 5038 - Remove "old-style" flexible array usage in ZFS.
5038 Remove "old-style" flexible array usage in ZFS.
Author: Justin T. Gibbs <justing@spectralogic.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Approved by: Richard Lowe <richlowe@richlowe.net>

References:
  https://www.illumos.org/issues/5038
  https://github.com/illumos/illumos-gate/commit/7f18da4

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-04-28 16:24:24 -07:00
Alex Reece
8951cb8dfb Illumos 4873 - zvol unmap calls can take a very long time for larger datasets
4873 zvol unmap calls can take a very long time for larger datasets
Author: Alex Reece <alex@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Paul Dagnelie <paul.dagnelie@delphix.com>
Reviewed by: Basil Crow <basil.crow@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Robert Mustacchi <rm@joyent.com>

References:
  https://www.illumos.org/issues/4873
  https://github.com/illumos/illumos-gate/commit/0f6d88a

Porting Notes:

dbuf_free_range():
  - reduce stack usage using kmem_alloc()
  - the sorted AVL tree will handle the spill block case correctly
    without all the special handling in the for() loop

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-04-28 16:24:03 -07:00
Jerry Jelinek
788eb90c4c Illumos 3897 - zfs filesystem and snapshot limits
3897 zfs filesystem and snapshot limits
Author: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>

References:
  https://www.illumos.org/issues/3897
  https://github.com/illumos/illumos-gate/commit/a2afb61

Porting Notes:

dsl_dataset_snapshot_check(): reduce stack usage using kmem_alloc().

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-04-28 16:22:51 -07:00
Isaac Huang
0336f3d001 Remove useless variable spa_active_count
This isn't required for the Linux port because the kernel tracks
if a module is busy.  The prototype for spa_busy() is also removed
since its definition was already removed.

Signed-off-by: Isaac Huang <he.huang@intel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3262
2015-04-27 09:22:05 -07:00
Justin T. Gibbs
ec8501ee12 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>

References:
  https://www.illumos.org/issues/5313
  https://github.com/illumos/illumos-gate/commit/fe319232

Ported-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3280
2015-04-24 15:16:56 -07:00
Ned Bass
4eb30c6864 Serialize access to spa->spa_feat_stats nvlist
The function spa_add_feature_stats() manipulates the shared nvlist
spa->spa_feat_stats in an unsafe concurrent manner. Add a mutex to
protect the list.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3335
2015-04-24 15:04:43 -07:00
Chunwei Chen
07012da668 Fix kernel panic due to tsd_exit in ZFS_EXIT(zsb)
The following panic would occur under certain heavy load:
[ 4692.202686] Kernel panic - not syncing: thread ffff8800c4f5dd60 terminating with rrw lock ffff8800da1b9c40 held
[ 4692.228053] CPU: 1 PID: 6250 Comm: mmap_deadlock Tainted: P           OE  3.18.10 #7

The culprit is that ZFS_EXIT(zsb) would call tsd_exit() every time, which
would purge all tsd data for the thread. However, ZFS_ENTER is designed to be
reentrant, so we cannot allow ZFS_EXIT to blindly purge tsd data.

Instead, we rely on the new behavior of tsd_set. When NULL is passed as the
new value to tsd_set, it will automatically remove the tsd entry specified the
the key for the current thread.

rrw_tsd_key and zfs_allow_log_key already calls tsd_set(key, NULL) when
they're done. The zfs_fsyncer_key relied on ZFS_EXIT(zsb) to call tsd_exit() to
do clean up. Now we explicitly call tsd_set(key, NULL) on them.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3247
2015-04-24 14:57:54 -07:00
Tim Chase
40d06e3c78 Mark all ZPL and ioctl functions as PF_FSTRANS
Prevent deadlocks by disabling direct reclaim during all ZPL and ioctl
calls as well as the l2arc and adapt ARC threads.

This obviates the need for MUTEX_FSTRANS so its previous uses and
definition have been eliminated.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3225
2015-04-03 11:38:59 -07:00
Prakash Surya
a4069eef2e Illumos 5695 - dmu_sync'ed holes do not retain birth time
5695 dmu_sync'ed holes do not retain birth time
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>

References:
  https://www.illumos.org/issues/5695
  https://github.com/illumos/illumos-gate/commit/70163ac

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3229
2015-03-27 14:51:34 -07:00
Ned Bass
95a6990d9a Add NULL guard in zfs_zrlock_class event class
The owner field could be NULL in some cases, so add a guard.  Shorten
__entry field names to fit assignment statements in 80 columns.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Fixes #3220
2015-03-27 14:45:32 -07:00
Brian Behlendorf
7d90f569b3 Check all vdev labels in 'zpool import'
When using 'zpool import' to scan for available pools prefer vdev names
which reference vdevs with more valid labels.  There should be two labels
at the start of the device and two labels at the end of the device.  If
labels are missing then the device has been damaged or is in some other
way incomplete.  Preferring names with fully intact labels helps weed out
bad paths and improves the likelihood of being able to import the pool.

This behavior only applies when scanning /dev/ for valid pools.  If a
cache file exists the pools described by the cache file will be used.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Closes #3145
Closes #2844
Closes #3107
2015-03-25 14:52:52 -07:00
Chris Dunlop
d07b7c7f21 Reduce size of zfs_sb_t: allocate z_hold_mtx separately
zfs_sb_t has grown to the point where using kmem_zalloc() for allocations
is triggering the 32k warning threshold.

We can't safely convert this entire allocation to use vmem_alloc() instead
of kmem_alloc() because the backing_dev_info structure is embedded here.
It depends on the bit_waitqueue() function which won't behave properly
when given a virtual address.

Instead, use vmem_alloc() to allocate the z_hold_mtx array separately.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Closes #3178
2015-03-24 13:17:44 -07:00
Brian Behlendorf
2cbb06b561 Restructure per-filesystem reclaim
Originally when the ARC prune callback was introduced the idea was
to register a single callback for the ZPL.  The ARC could invoke this
call back if it needed the ZPL to drop dentries, inodes, or other
cache objects which might be pinning buffers in the ARC.  The ZPL
would iterate over all ZFS super blocks and perform the reclaim.

For the most part this design has worked well but due to limitations
in 2.6.35 and earlier kernels there were some problems.  This patch
is designed to address those issues.

1) iterate_supers_type() is not provided by all kernels which makes
it impossible to safely iterate over all zpl_fs_type filesystems in
a single callback.  The most straight forward and portable way to
resolve this is to register a callback per-filesystem during mount.
The arc_*_prune_callback() functions have always supported multiple
callbacks so this is functionally a very small change.

2) Commit 050d22b removed the non-portable shrink_dcache_memory()
and shrink_icache_memory() functions and didn't replace them with
equivalent functionality.  This meant that for Linux 3.1 and older
kernels the ARC had no mechanism to drop dentries and inodes from
the caches if needed.  This patch adds that missing functionality
by calling shrink_dcache_parent() to release dentries which may be
pinning inodes.  This will result in all unused cache entries being
dropped which is a bit heavy handed but it's the only interface
available for old kernels.

3) A zpl_drop_inode() callback is registered for kernels older than
2.6.35 which do not support the .evict_inode callback.  This ensures
that when the last reference on an inode is dropped it is immediately
removed from the cache.  If this isn't done than inode can end up on
the global unused LRU with no mechanism available to ZFS to drop them.
Since the ARC buffers are not dropped the hottest inodes can still
be recreated without performing disk IO.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Pavel Snajdr <snajpa@snajpa.net>
Issue #3160
2015-03-20 10:35:20 -07:00
Justin T. Gibbs
4c7b7eedcd Illumos 5630 - stale bonus buffer in recycled dnode_t leads to data corruption
5630 stale bonus buffer in recycled dnode_t leads to data corruption
Author: Justin T. Gibbs <justing@spectralogic.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>

References:
  https://www.illumos.org/issues/5630
  https://github.com/illumos/illumos-gate/commit/cd485b4

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Issue #3172
2015-03-12 15:40:39 -07:00
Ned Bass
417104bdd3 Use cached feature info in spa_add_feature_stats()
Avoid issuing I/O to the pool when retrieving feature flags information.
Trying to read the ZAPs from disk means that zpool clear would hang if
the pool is suspended and recovery would require a reboot. To keep the
feature stats resident in memory, we hang a cached nvlist off of the
spa.  It is built up from disk the first time spa_add_feature_stats() is
called, and refreshed thereafter using the cached feature reference
counts. spa_add_feature_stats() gets called at pool import time so we
can be sure the cached nvlist will be available if the pool is later
suspended.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3082
2015-03-05 14:11:10 -08:00
Brian Behlendorf
8c45def24a Linux 4.0 compat: bdi_setup_and_register()
The 'capabilities' argument which was passed to bdi_setup_and_register()
has been removed.  File systems should no longer pass BDI_CAP_MAP_COPY.
For our purposes this means there are now three different interfaces
which must be handled.  A zpl_bdi_setup_and_register() wrapper function
has been introduced to provide a single interface to the ZPL code.

* 2.6.32 - 2.6.33, bdi_setup_and_register() is not exported.
* 2.6.34 - 3.19, bdi_setup_and_register() takes 3 arguments.
* 4.0 - x.y, bdi_setup_and_register() takes 2 arguments.

I've also taken this opportunity to remove HAVE_BDI because kernels
older then 2.6.32 are no longer supported.  All kernels newer than
this will have one of the above interfaces.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Closes #3128
2015-03-03 10:49:45 -08:00
Brian Behlendorf
4ec15b8dcf Use MUTEX_FSTRANS mutex type
There are regions in the ZFS code where it is desirable to be able
to be set PF_FSTRANS while a specific mutex is held.  The ZFS code
could be updated to set/clear this flag in all the correct places,
but this is undesirable for a few reasons.

1) It would require changes to a significant amount of the ZFS
   code.  This would complicate applying patches from upstream.

2) It would be easy to accidentally miss a critical region in
   the initial patch or to have an future change introduce a
   new one.

Both of these concerns can be addressed by using a new mutex type
which is responsible for managing PF_FSTRANS, support for which was
added to the SPL in commit zfsonlinux/spl@9099312 - Merge branch
'kmem-rework'.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #3050
Closes #3055
Closes #3062
Closes #3132
Closes #3142
Closes #2983
2015-03-03 10:46:40 -08:00
Jörg Thalheim
534759fad3 Linux 3.19 compat: file_inode was added
struct access f->f_dentry->d_inode was replaced by accessor function
file_inode(f)

Signed-off-by: Joerg Thalheim <joerg@higgsboson.tk>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3084
2015-02-10 11:24:51 -08:00
Chunwei Chen
53698a453d Read spl_hostid module parameter before gethostid()
If spl_hostid is set via module parameter, it's likely different from
gethostid(). Therefore, the userspace tool should read it first before
falling back to gethostid().

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3034
2015-02-04 16:44:53 -08:00
Brian Behlendorf
81971b137a Revert "SA spill block cache"
The SA spill_cache was originally introduced to avoid the need to
perform large kmem or vmem allocations.  Instead a small dedicated
cache of preallocated SA buffers was kept.

This solution was viable while the maximum block size was limited
to 128K.  But with the planned increase of the maximum block size
to 16M callers need to migrate to the zio_buf_alloc().  However,
they should be aware this interface is expected to change again
once the zio buffers are fully backed by scatter-gather lists.

Alternately, if the callers know these buffers will never be large
or be infrequently accessed they may kmem_alloc() or vmem_alloc()
the needed temporary space.

This change has the additional benegit of bringing the code back
inline with the upstream Illumos source.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-01-16 14:41:28 -08:00
Brian Behlendorf
285b29d959 Revert "Pre-allocate vdev I/O buffers"
Commit 86dd0fd added preallocated I/O buffers.  This is no longer
required after the recent kmem changes designed to make our memory
allocation interfaces behave more like those found on Illumos.  A
deadlock in this situation is no longer possible.

However, these allocations still have the potential to be expensive.
So a potential future optimization might be to perform then KM_NOSLEEP
so that they either succeed of fail quicky.  Either case is acceptable
here because we can safely abort the aggregation.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-01-16 14:41:28 -08:00
Brian Behlendorf
60e1eda929 Add kmem_cache.h include to default context
As part of the spl kmem/vmem refactoring the kmem_cache_* functions
were split in to their own kmem_cache.h header.  This was done in
part so that kmem_* consumers would not be forced to include the
kmem_cache_* functions which mask several Linux SLAB/SLAB functions.

Because of this we now much explicitly include kmem_cache.h in the
zfs_context.h.  However, consumers such as Lustre which need access
to the KM_FLAGS but not the kmem_cache_* functions can now safely
just include kmem.h.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-01-16 14:41:28 -08:00
Brian Behlendorf
79c76d5b65 Change KM_PUSHPAGE -> KM_SLEEP
By marking DMU transaction processing contexts with PF_FSTRANS
we can revert the KM_PUSHPAGE -> KM_SLEEP changes.  This brings
us back in line with upstream.  In some cases this means simply
swapping the flags back.  For others fnvlist_alloc() was replaced
by nvlist_alloc(..., KM_PUSHPAGE) and must be reverted back to
fnvlist_alloc() which assumes KM_SLEEP.

The one place KM_PUSHPAGE is kept is when allocating ARC buffers
which allows us to dip in to reserved memory.  This is again the
same as upstream.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-01-16 14:41:26 -08:00
Brian Behlendorf
efcd79a883 Retire KM_NODEBUG
Callers of kmem_alloc() which passed the KM_NODEBUG flag to suppress
the large allocation warning have been replaced by vmem_alloc() as
appropriate.  The updated vmem_alloc() call will not print a warning
regardless of the size of the allocation.

A careful reader will notice that not all callers have been changed
to vmem_alloc().  Some have only had the KM_NODEBUG flag removed.
This was possible because the default warning threshold has been
increased to 32k.  This is desirable because it minimizes the need
for Linux specific code changes.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-01-16 14:40:32 -08:00
Brian Behlendorf
92119cc259 Mark IO pipeline with PF_FSTRANS
In order to avoid deadlocking in the IO pipeline it is critical that
pageout be avoided during direct memory reclaim.  This ensures that
the pipeline threads can always make forward progress and never end
up blocking on a DMU transaction.  For this very reason Linux now
provides the PF_FSTRANS flag which may be set in the process context.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-01-16 14:28:05 -08:00
Ned Bass
49ee64e5e6 Remove duplicate typedefs from trace.h
Older versions of GCC (e.g. GCC 4.4.7 on RHEL6) do not allow duplicate
typedef declarations with the same type. The trace.h header contains
some typedefs to avoid 'unknown type' errors for C files that haven't
declared the type in question. But this causes build failures for C
files that have already declared the type. Newer versions of GCC (e.g.
v4.6) allow duplicate typedefs with the same type unless pedantic error
checking is in force. To support the older versions we need to remove
the duplicate typedefs.

Removal of the typedefs means we can't built tracepoints code using
those types unless the required headers have been included. To
facilitate this, all tracepoint event declarations have been moved out
of trace.h into separate headers. Each new header is explicitly included
from the C file that uses the events defined therein. The trace.h header
is still indirectly included form zfs_context.h and provides the
implementation of the dprintf(), dbgmsg(), and SET_ERROR() interfaces.
This makes those interfaces readily available throughout the code base.
The macros that redefine DTRACE_PROBE* to use Linux tracepoints are also
still provided by trace.h, so it is a prerequisite for the other
trace_*.h headers.

These new Linux implementation-specific headers do introduce a small
divergence from upstream ZFS in several core C files, but this should
not present a significant maintenance burden.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2953
2015-01-06 16:53:24 -08:00
Ned Bass
aaed7c408c Explicitly include SPL compat headers
Inclusion of SPL compatibility headers was moved out of the public
header sys/types.h to avoid conflicts with external packages.  Include a
few compatiblity headers explicitly to cope with that change.  Also,
sort some linux-specific inclusions alphabetically.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2898
2014-11-19 12:30:39 -05:00
Prakash Surya
0b39b9f96f Swap DTRACE_PROBE* with Linux tracepoints
This patch leverages Linux tracepoints from within the ZFS on Linux
code base. It also refactors the debug code to bring it back in sync
with Illumos.

The information exported via tracepoints can be used for a variety of
reasons (e.g. debugging, tuning, general exploration/understanding,
etc). It is advantageous to use Linux tracepoints as the mechanism to
export this kind of information (as opposed to something else) for a
number of reasons:

    * A number of external tools can make use of our tracepoints
      "automatically" (e.g. perf, systemtap)
    * Tracepoints are designed to be extremely cheap when disabled
    * It's one of the "accepted" ways to export this kind of
      information; many other kernel subsystems use tracepoints too.

Unfortunately, though, there are a few caveats as well:

    * Linux tracepoints appear to only be available to GPL licensed
      modules due to the way certain kernel functions are exported.
      Thus, to actually make use of the tracepoints introduced by this
      patch, one might have to patch and re-compile the kernel;
      exporting the necessary functions to non-GPL modules.

    * Prior to upstream kernel version v3.14-rc6-30-g66cc69e, Linux
      tracepoints are not available for unsigned kernel modules
      (tracepoints will get disabled due to the module's 'F' taint).
      Thus, one either has to sign the zfs kernel module prior to
      loading it, or use a kernel versioned v3.14-rc6-30-g66cc69e or
      newer.

Assuming the above two requirements are satisfied, lets look at an
example of how this patch can be used and what information it exposes
(all commands run as 'root'):

    # list all zfs tracepoints available

    $ ls /sys/kernel/debug/tracing/events/zfs
    enable              filter              zfs_arc__delete
    zfs_arc__evict      zfs_arc__hit        zfs_arc__miss
    zfs_l2arc__evict    zfs_l2arc__hit      zfs_l2arc__iodone
    zfs_l2arc__miss     zfs_l2arc__read     zfs_l2arc__write
    zfs_new_state__mfu  zfs_new_state__mru

    # enable all zfs tracepoints, clear the tracepoint ring buffer

    $ echo 1 > /sys/kernel/debug/tracing/events/zfs/enable
    $ echo 0 > /sys/kernel/debug/tracing/trace

    # import zpool called 'tank', inspect tracepoint data (each line was
    # truncated, they're too long for a commit message otherwise)

    $ zpool import tank
    $ cat /sys/kernel/debug/tracing/trace | head -n35
    # tracer: nop
    #
    # entries-in-buffer/entries-written: 1219/1219   #P:8
    #
    #                              _-----=> irqs-off
    #                             / _----=> need-resched
    #                            | / _---=> hardirq/softirq
    #                            || / _--=> preempt-depth
    #                            ||| /     delay
    #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
    #              | |       |   ||||       |         |
            lt-zpool-30132 [003] .... 91344.200050: zfs_arc__miss: hdr...
          z_rd_int/0-30156 [003] .... 91344.200611: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.201173: zfs_arc__miss: hdr...
          z_rd_int/1-30157 [003] .... 91344.201756: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.201795: zfs_arc__miss: hdr...
          z_rd_int/2-30158 [003] .... 91344.202099: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.202126: zfs_arc__hit: hdr ...
            lt-zpool-30132 [003] .... 91344.202130: zfs_arc__hit: hdr ...
            lt-zpool-30132 [003] .... 91344.202134: zfs_arc__hit: hdr ...
            lt-zpool-30132 [003] .... 91344.202146: zfs_arc__miss: hdr...
          z_rd_int/3-30159 [003] .... 91344.202457: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.202484: zfs_arc__miss: hdr...
          z_rd_int/4-30160 [003] .... 91344.202866: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.202891: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.203034: zfs_arc__miss: hdr...
          z_rd_iss/1-30149 [001] .... 91344.203749: zfs_new_state__mru...
            lt-zpool-30132 [001] .... 91344.203789: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.203878: zfs_arc__miss: hdr...
          z_rd_iss/3-30151 [001] .... 91344.204315: zfs_new_state__mru...
            lt-zpool-30132 [001] .... 91344.204332: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.204337: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.204352: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.204356: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.204360: zfs_arc__hit: hdr ...

To highlight the kind of detailed information that is being exported
using this infrastructure, I've taken the first tracepoint line from the
output above and reformatted it such that it fits in 80 columns:

    lt-zpool-30132 [003] .... 91344.200050: zfs_arc__miss:
        hdr {
            dva 0x1:0x40082
            birth 15491
            cksum0 0x163edbff3a
            flags 0x640
            datacnt 1
            type 1
            size 2048
            spa 3133524293419867460
            state_type 0
            access 0
            mru_hits 0
            mru_ghost_hits 0
            mfu_hits 0
            mfu_ghost_hits 0
            l2_hits 0
            refcount 1
        } bp {
            dva0 0x1:0x40082
            dva1 0x1:0x3000e5
            dva2 0x1:0x5a006e
            cksum 0x163edbff3a:0x75af30b3dd6:0x1499263ff5f2b:0x288bd118815e00
            lsize 2048
        } zb {
            objset 0
            object 0
            level -1
            blkid 0
        }

For the specific tracepoint shown here, 'zfs_arc__miss', data is
exported detailing the arc_buf_hdr_t (hdr), blkptr_t (bp), and
zbookmark_t (zb) that caused the ARC miss (down to the exact DVA!).
This kind of precise and detailed information can be extremely valuable
when trying to answer certain kinds of questions.

For anybody unfamiliar but looking to build on this, I found the XFS
source code along with the following three web links to be extremely
helpful:

    * http://lwn.net/Articles/379903/
    * http://lwn.net/Articles/381064/
    * http://lwn.net/Articles/383362/

I should also node the more "boring" aspects of this patch:

    * The ZFS_LINUX_COMPILE_IFELSE autoconf macro was modified to
       support a sixth paramter. This parameter is used to populate the
       contents of the new conftest.h file. If no sixth parameter is
       provided, conftest.h will be empty.

    * The ZFS_LINUX_TRY_COMPILE_HEADER autoconf macro was introduced.
      This macro is nearly identical to the ZFS_LINUX_TRY_COMPILE macro,
      except it has support for a fifth option that is then passed as
      the sixth parameter to ZFS_LINUX_COMPILE_IFELSE.

These autoconf changes were needed to test the availability of the Linux
tracepoint macros. Due to the odd nature of the Linux tracepoint macro
API, a separate ".h" must be created (the path and filename is used
internally by the kernel's define_trace.h file).

    * The HAVE_DECLARE_EVENT_CLASS autoconf macro was introduced. This
      is to determine if we can safely enable the Linux tracepoint
      functionality. We need to selectively disable the tracepoint code
      due to the kernel exporting certain functions as GPL only. Without
      this check, the build process will fail at link time.

In addition, the SET_ERROR macro was modified into a tracepoint as well.
To do this, the 'sdt.h' file was moved into the 'include/sys' directory
and now contains a userspace portion and a kernel space portion. The
dprintf and zfs_dbgmsg* interfaces are now implemented as tracepoint as
well.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-11-17 11:13:55 -08:00