Commit Graph

2774 Commits

Author SHA1 Message Date
Prakash Surya
99573cc053 Timeout waiting for ZVOL device to be created
We've seen cases where after creating a ZVOL, the ZVOL device node in
"/dev" isn't generated after 20 seconds of waiting, which is the point
at which our applications gives up on waiting and reports an error.

The workload when this occurs is to "refresh" 400+ ZVOLs roughly at the
same time, based on a policy set by the user. This refresh operation
will destroy the ZVOL, and re-create it based on a snapshot.

When this occurs, we see many hundreds of entries on the "z_zvol" taskq
(based on inspection of the /proc/spl/taskq-all file). Many of the
entries on the taskq end up in the "zvol_remove_minors_impl" function,
and I've measured the latency of that function:

Function = zvol_remove_minors_impl
msecs               : count     distribution
  0 -> 1          : 0        |                                        |
  2 -> 3          : 0        |                                        |
  4 -> 7          : 1        |                                        |
  8 -> 15         : 0        |                                        |
 16 -> 31         : 0        |                                        |
 32 -> 63         : 0        |                                        |
 64 -> 127        : 1        |                                        |
128 -> 255        : 45       |****************************************|
256 -> 511        : 5        |****                                    |

That data is from a 10 second sample, using the BCC "funclatency" tool.
As we can see, in this 10 second sample, most calls took 128ms at a
minimum. Thus, some basic math tells us that in any 20 second interval,
we could only process at most about 150 removals, which is much less
than the 400+ that'll occur based on the workload.

As a result of this, and since all ZVOL minor operations will go through
the single threaded "z_zvol" taskq, the latency for creating a single
ZVOL device can be unreasonably large due to other ZVOL activity on the
system. In our case, it's large enough to cause the application to
generate an error and fail the operation.

When profiling the "zvol_remove_minors_impl" function, I saw that most
of the time in the function was spent off-cpu, blocked in the function
"taskq_wait_outstanding". How this works, is "zvol_remove_minors_impl"
will dispatch calls to "zvol_free" using the "system_taskq", and then
the "taskq_wait_outstanding" function is used to wait for all of those
dispatched calls to occur before "zvol_remove_minors_impl" will return.

As far as I can tell, "zvol_remove_minors_impl" doesn't necessarily have
to wait for all calls to "zvol_free" to occur before it returns. Thus,
this change removes the call to "taskq_wait_oustanding", so that calls
to "zvol_free" don't affect the latency of "zvol_remove_minors_impl".

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Gallagher <john.gallagher@delphix.com>
Signed-off-by: Prakash Surya <prakash.surya@delphix.com>
Closes #9380
2019-10-01 12:33:12 -07:00
Matthew Macy
7bb0c29468 OpenZFS restructuring - zfs_ioctl
Refactor the zfs ioctls in to platform dependent and independent bits.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Sean Eric Fagan <sef@ixsystems.com>
Signed-off-by: Matthew Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9301
2019-09-27 10:46:28 -07:00
Brian Behlendorf
f81d5ef686
Add warning for zfs_vdev_elevator option removal
Originally the zfs_vdev_elevator module option was added as a
convenience so the requested elevator would be automatically set
on the underlying block devices.  At the time this was simple
because the kernel provided an API function which did exactly this.

This API was then removed in the Linux 4.12 kernel which prompted
us to add compatibly code to set the elevator via a usermodehelper.
While well intentioned this introduced a bug which could cause a
system hang, that issue was subsequently fixed by commit 2a0d4188.

In order to avoid future bugs in this area, and to simplify the code,
this functionality is being deprecated.  A console warning has been
added to notify any existing consumers and the documentation updated
accordingly.  This option will remain for the lifetime of the 0.8.x
series for compatibility but if planned to be phased out of master.

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #8664
Closes #9317
2019-09-25 09:23:29 -07:00
Matthew Macy
5df7e9d85c OpenZFS restructuring - zvol
Refactor the zvol in to platform dependent and independent bits.

Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9295
2019-09-25 09:20:30 -07:00
loli10K
d359e99c38 diff_cb() does not handle large dnodes
Trying to 'zfs diff' a snapshot with large dnodes will incorrectly try
to access its interior slots when dnodesize > sizeof(dnode_phys_t).
This is normally not an issue because the interior slots are
zero-filled, which report_dnode() handles calling
report_free_dnode_range(). However this is not the case for encrypted
large dnodes or filesystem using many SA based xattrs where the extra
data past the legacy dnode size boundary is interpreted as a
dnode_phys_t.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #7678 
Closes #8931 
Closes #9343
2019-09-24 12:01:37 -07:00
Kody A Kantor
d49d7336dd Disabled resilver_defer feature leads to looping resilvers
When a disk is replaced with another on a pool with the resilver_defer
feature present, but not enabled the resilver activity restarts during
each spa_sync. This patch checks to make sure that the resilver_defer
feature is first enabled before requesting a deferred resilver.

This was originally fixed in illumos-joyent as OS-7982.

Reviewed-by: Chris Dunlop <chris@onthe.net.au>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Signed-off-by: Kody A Kantor <kody@kkantor.com>
External-issue: illumos-joyent OS-7982
Closes #9299 
Closes #9338
2019-09-22 15:25:39 -07:00
Andriy Gapon
dd262c9681 Fix dsl_scan_ds_clone_swapped logic
The was incorrect with respect to swapping dataset IDs both in the
on-disk ZAP object and the in-memory queue.

In both cases, if ds1 was already present, then it would be first
replaced with ds2 and then ds would be replaced back with ds1.
Also, both cases did not properly handle a situation where both ds1 and
ds2 are already queued.  A duplicate insertion would be attempted and
its failure would result in a panic.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Signed-off-by: Andriy Gapon <avg@FreeBSD.org>
Closes #9140 
Closes #9163
2019-09-18 09:04:45 -07:00
loli10K
fcd37b622b Device removal of indirect vdev panics the kernel
This commit fixes a NULL pointer dereference triggered in
spa_vdev_remove_top_check() by trying to "zpool remove" an indirect
vdev.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #9327
2019-09-16 10:46:59 -07:00
loli10K
b24771a8c9 Prevent gcc -Werror=maybe-uninitialized warnings in spa_wait_common()
This commit fixes the following build failure detected on Debian9
(GCC 6.3.0):

     CC [M]  module/zfs/spa.o
   module/zfs/spa.c: In function ‘spa_wait_common.part.31’:
   module/zfs/spa.c:9468:6: error: ‘in_progress’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
      if (!in_progress || spa->spa_waiters_cancel || error)
         ^
   cc1: all warnings being treated as errors

Reviewed-by: Chris Dunlop <chris@onthe.net.au>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Gallagher <john.gallagher@delphix.com>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #9326
2019-09-16 10:46:02 -07:00
Tom Caputi
637f0c6019 Fix clone handling with encryption roots
Currently, spa_keystore_change_key_sync_impl() does not recurse
into clones when updating encryption roots for either a call to
'zfs promote' or 'zfs change-key'. This can cause children of
these clones to end up in a state where they point to the wrong
dataset as the encryption root. It can also trigger ASSERTs in
some cases where the code checks reference counts on wrapping
keys. This patch fixes this issue by ensuring that this function
properly recurses into clones during processing.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alek Pinchuk <apinchuk@datto.com>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #9267 
Closes #9294
2019-09-16 10:07:33 -07:00
loli10K
2a0d41889e Scrubbing root pools may deadlock on kernels without elevator_change() (#9321)
Originally the zfs_vdev_elevator module option was added as a
convenience so the requested elevator would be automatically set
on the underlying block devices. At the time this was simple
because the kernel provided an API function which did exactly this.

This API was then removed in the Linux 4.12 kernel which prompted
us to add compatibly code to set the elevator via a usermodehelper.

Unfortunately changing the evelator via usermodehelper requires reading
some userland binaries, most notably modprobe(8) or sh(1), from a zfs
dataset on systems with root-on-zfs. This can deadlock the system if
used during the following call path because it may need, if the data
is not already cached in the ARC, reading directly from disk while
holding the spa config lock as a writer:

  zfs_ioc_pool_scan()
    -> spa_scan()
      -> spa_scan()
        -> vdev_reopen()
          -> vdev_elevator_switch()
            -> call_usermodehelper()

While the usermodehelper waits sh(1), modprobe(8) is blocked in the
ZIO pipeline trying to read from disk:

  INFO: task modprobe:2650 blocked for more than 10 seconds.
       Tainted: P           OE     5.2.14
  modprobe        D    0  2650    206 0x00000000
  Call Trace:
   ? __schedule+0x244/0x5f0
   schedule+0x2f/0xa0
   cv_wait_common+0x156/0x290 [spl]
   ? do_wait_intr_irq+0xb0/0xb0
   spa_config_enter+0x13b/0x1e0 [zfs]
   zio_vdev_io_start+0x51d/0x590 [zfs]
   ? tsd_get_by_thread+0x3b/0x80 [spl]
   zio_nowait+0x142/0x2f0 [zfs]
   arc_read+0xb2d/0x19d0 [zfs]
   ...
   zpl_iter_read+0xfa/0x170 [zfs]
   new_sync_read+0x124/0x1b0
   vfs_read+0x91/0x140
   ksys_read+0x59/0xd0
   do_syscall_64+0x4f/0x130
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

This commit changes how we use the usermodehelper functionality from
synchronous (UMH_WAIT_PROC) to asynchronous (UMH_NO_WAIT) which prevents
scrubs, and other vdev_elevator_switch() consumers, from triggering the
aforementioned issue.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Issue #8664 
Closes #9321
2019-09-13 18:09:59 -07:00
John Gallagher
e60e158eff Add subcommand to wait for background zfs activity to complete
Currently the best way to wait for the completion of a long-running
operation in a pool, like a scrub or device removal, is to poll 'zpool
status' and parse its output, which is neither efficient nor convenient.

This change adds a 'wait' subcommand to the zpool command. When invoked,
'zpool wait' will block until a specified type of background activity
completes. Currently, this subcommand can wait for any of the following:

 - Scrubs or resilvers to complete
 - Devices to initialized
 - Devices to be replaced
 - Devices to be removed
 - Checkpoints to be discarded
 - Background freeing to complete

For example, a scrub that is in progress could be waited for by running

    zpool wait -t scrub <pool>

This also adds a -w flag to the attach, checkpoint, initialize, replace,
remove, and scrub subcommands. When used, this flag makes the operations
kicked off by these subcommands synchronous instead of asynchronous.

This functionality is implemented using a new ioctl. The type of
activity to wait for is provided as input to the ioctl, and the ioctl
blocks until all activity of that type has completed. An ioctl was used
over other methods of kernel-userspace communiction primarily for the
sake of portability.

Porting Notes:
This is ported from Delphix OS change DLPX-44432. The following changes
were made while porting:

 - Added ZoL-style ioctl input declaration.
 - Reorganized error handling in zpool_initialize in libzfs to integrate
   better with changes made for TRIM support.
 - Fixed check for whether a checkpoint discard is in progress.
   Previously it also waited if the pool had a checkpoint, instead of
   just if a checkpoint was being discarded.
 - Exposed zfs_initialize_chunk_size as a ZoL-style tunable.
 - Updated more existing tests to make use of new 'zpool wait'
   functionality, tests that don't exist in Delphix OS.
 - Used existing ZoL tunable zfs_scan_suspend_progress, together with
   zinject, in place of a new tunable zfs_scan_max_blks_per_txg.
 - Added support for a non-integral interval argument to zpool wait.

Future work:
ZoL has support for trimming devices, which Delphix OS does not. In the
future, 'zpool wait' could be extended to add the ability to wait for
trim operations to complete.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: John Gallagher <john.gallagher@delphix.com>
Closes #9162
2019-09-13 18:09:06 -07:00
Chengfei ZHu
7238cbd4d3 QAT related bug fixes
1. Fix issue:  Kernel BUG with QAT during decompression  #9276.
   Now it is uninterruptible for a specific given QAT request,
   but Ctrl-C interrupt still works in user-space process.

2. Copy the digest result to the buffer only when doing encryption,
   and vise-versa for decryption.

Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chengfei Zhu <chengfeix.zhu@intel.com>
Closes #9276 
Closes #9303
2019-09-12 13:33:44 -07:00
Matthew Macy
b01a6574ae Move objnode handling to common code
objnode is OS agnostic and used only by dmu_redact.c.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9315
2019-09-12 13:31:09 -07:00
Matthew Macy
74756182d2 Enable compiler to typecheck logging
Annotate spa logging declarations with printflike
Workaround gcc bug (non disable-able warning) by
replacing "" with " "

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9316
2019-09-12 13:28:26 -07:00
Matthew Macy
d66620681d OpenZFS restructuring - move linux tracing code to platform directories
Move Linux specific tracing headers and source to platform directories
and update the build system.

Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9290
2019-09-11 14:25:53 -07:00
Tom Caputi
5815f7ac30 Fix stalled txg with repeated noop scans
Currently, the DSL scan code figures out when it should suspend
processing and allow a txg to continue by calling the function
dsl_scan_check_suspend(). Unfortunately, this function only
allows the scan to suspend at a level 0 block. In the event that
the system is scanning a bunch of empty snapshots or a resilver
is running with a high enough scn_cur_min_txg, the scan will
stop processing each dataset at the root level, deciding it
has nothing left to do. This means that the check_suspend
function is never called and the txg remains stuck until a
dataset is found that has data to scan.

This patch fixes the problem by allowing scans to suspend at
the root level of the objset. For backwards compatibility, we
use the bookmark <objsetid, 0, 0, 0> when we suspend here so
that older versions of the code will work as intended.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #9300
2019-09-11 11:16:48 -07:00
Brian Behlendorf
25f06d677a
Fix /etc/hostid on root pool deadlock
Accidentally introduced by dc04a8c which now takes the SCL_VDEV lock
as a reader in zfs_blkptr_verify().  A deadlock can occur if the
/etc/hostid file resides on a dataset in the same pool.  This is
because reading the /etc/hostid file may occur while the caller is
holding the SCL_VDEV lock as a writer.  For example, to perform a
`zpool attach` as shown in the abbreviated stack below.

To resolve the issue we cache the system's hostid when initializing
the spa_t, or when modifying the multihost property.  The cached
value is then relied upon for subsequent accesses.

Call Trace:
    spa_config_enter+0x1e8/0x350 [zfs]
    zfs_blkptr_verify+0x33c/0x4f0 [zfs] <--- trying read lock
    zio_read+0x6c/0x140 [zfs]
    ...
    vfs_read+0xfc/0x1e0
    kernel_read+0x50/0x90
    ...
    spa_get_hostid+0x1c/0x38 [zfs]
    spa_config_generate+0x1a0/0x610 [zfs]
    vdev_label_init+0xa0/0xc80 [zfs]
    vdev_create+0x98/0xe0 [zfs]
    spa_vdev_attach+0x14c/0xb40 [zfs] <--- grabbed write lock

Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9256 
Closes #9285
2019-09-10 13:42:30 -07:00
Brian Behlendorf
b88ca2acf5
Enable SIMD for encryption
When adding the SIMD compatibility code in e5db313 the decryption of a
dataset wrapping key was left in a user thread context.  This was done
intentionally since it's a relatively infrequent operation.  However,
this also meant that the encryption context templates were initialized
using the generic operations.  Therefore, subsequent encryption and
decryption operations would use the generic implementation even when
executed by an I/O pipeline thread.

Resolve the issue by initializing the context templates in an I/O
pipeline thread.  And by updating zio_do_crypt_uio() to dispatch any
encryption operations to a pipeline thread when called from the user
context.  For example, when performing a read from the ARC.

Tested-by: Attila Fülöp <attila@fueloep.org>
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9215
Closes #9296
2019-09-10 10:45:46 -07:00
Matthew Macy
bced7e3aaa OpenZFS restructuring - move platform specific sources
Move platform specific Linux source under module/os/linux/
and update the build system accordingly.  Additional code
restructuring will follow to make the common code fully
portable.
    
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Macy <mmacy@FreeBSD.org>
Closes #9206
2019-09-06 11:26:26 -07:00
Matthew Macy
03fdcb9adc Make module tunables cross platform
Adds ZFS_MODULE_PARAM to abstract module parameter
setting to operating systems other than Linux.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9230
2019-09-05 14:49:49 -07:00
Serapheim Dimitropoulos
65a91b166e metaslab_verify_weight_and_frag() shouldn't cause side-effects
`metaslab_verify_weight_and_frag()` a verification function and
by the end of it there shouldn't be any side-effects.

The function calls `metaslab_weight()` which in turn calls
`metaslab_set_fragmentation()`. The latter can dirty and otherwise
not dirty metaslab fro the next TXGand set `metaslab_condense_wanted`
if the spacemaps were just upgraded (meaning we just enabled the
SPACEMAP_HISTOGRAM feature through upgrade).

This patch adds a new flag as a parameter to `metaslab_weight()` and
`metaslab_set_fragmentation()` making the dirtying of the metaslab
optional.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #9185 
Closes #9282
2019-09-05 09:57:55 -07:00
Matthew Macy
006e9a4088 OpenZFS restructuring - move platform specific headers
Move platform specific Linux headers under include/os/linux/.
Update the build system accordingly to detect the platform.
This lays some of the initial groundwork to supporting building
for other platforms.

As part of this change it was necessary to create both a user
and kernel space sys/simd.h header which can be included in
either context.  No functional change, the source has been
refactored and the relevant #include's updated.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Signed-off-by: Matthew Macy <mmacy@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9198
2019-09-05 09:34:54 -07:00
Igor K
e242b67cee Fix panic on DilOS with kstat per dataset statistics
Account for ZFS_MAX_DATASET_NAME_LEN in kstat data size.  This value
is ignored in the Linux kstat code but resolves the issue for other
platforms.

Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Igor Kozhukhov <igor@dilos.org>
Closes #9254 
Closes #9151
2019-09-03 12:12:31 -07:00
Andriy Gapon
ebeb6f23bf Always refuse receving non-resume stream when resume state exists
This fixes a hole in the situation where the resume state is left from
receiving a new dataset and, so, the state is set on the dataset itself
(as opposed to %recv child).

Additionally, distinguish incremental and resume streams in error
messages.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andriy Gapon <avg@FreeBSD.org>
Closes #9252
2019-09-03 10:56:55 -07:00
loli10K
6988f3ed9a Fix Intel QAT / ZFS compatibility on v4.7.1+ kernels
This change use the compat code introduced in 9cc1844a.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #9268 
Closes #9269
2019-09-03 10:36:33 -07:00
George Wilson
1e52716257 maxinflight can overflow in spa_load_verify_cb()
When running on larger memory systems, we can overflow the value of
maxinflight. This can result in maxinflight having a value of 0 causing
the system to hang.

Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Wilson <george.wilson@delphix.com>
Closes #9272
2019-09-02 19:17:51 -07:00
Andrea Gelmini
e1cfd73f7f Fix typos in module/zfs/
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #9240
2019-09-02 17:56:41 -07:00
Andrea Gelmini
9f5c1bc609 Fix typos in module/
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #9241
2019-08-30 14:32:18 -07:00
Andrea Gelmini
9d40bdf414 Fix typos in modules/icp/
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #9239
2019-08-30 14:26:07 -07:00
Paul Dagnelie
475aa97cab Prevent metaslab_sync panic due to spa_final_dirty_txg
If a pool enables the SPACEMAP_HISTOGRAM feature shortly before being
exported, we can enter a situation that causes a kernel panic. Any metaslabs
that are loaded during the final dirty txg and haven't already been condensed
will cause metaslab_sync to proceed after the final dirty txg so that the
condense can be performed, which there are assertions to prevent. Because of
the nature of this issue, there are a number of ways we can enter this
state. Rather than try to prevent each of them one by one, potentially missing
some edge cases, we instead cut it off at the point of intersection; by
preventing metaslab_sync from proceeding if it would only do so to perform a
condense and we're past the final dirty txg, we preserve the utility of the
existing asserts while preventing this particular issue.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #9185
Closes #9186
Closes #9231
Closes #9253
2019-08-30 09:28:31 -07:00
Paul Dagnelie
eef0f4d84e Keep more metaslabs loaded
With the other metaslab changes loaded onto a system, we can 
significantly reduce the memory usage of each loaded metaslab and 
unload them on demand if there is memory pressure. However, none 
of those changes actually result in us keeping more metaslabs loaded. 
If we don't keep more metaslabs loaded, we will still have to wait 
for demand-loading to finish when no loaded metaslab can satisfy our 
allocation, which can cause ZIL performance issues. In addition,
performance is traditionally measured by IOs per unit time, while 
unloading is currently done on a txg-count basis. Txgs can take a 
widely varying range of times, from tenths of a second to several 
seconds. This can result in confusing, hard to predict behavior.

This change simply adds a time-based component to metaslab unloading. 
A metaslab will remain loaded for one minute and 8 txgs (by default) 
after it was last used, unless it is evicted due to memory pressure.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
External-issue: DLPX-65016
External-issue: DLPX-65047
Closes #9197
2019-08-29 10:20:36 -07:00
Tony Nguyen
8d04284281 Use smaller default slack/delta value for schedule_hrtimeout_range()
For interrupt coalescing, cv_timedwait_hires() uses a 100us slack/delta
for calls to schedule_hrtimeout_range(). This 100us slack can be costly
for small writes.

This change improves small write performance by passing resolution `res`
parameter to schedule_hrtimeout_range() to be used as delta/slack. A new
tunable `spl_schedule_hrtimeout_slack_us` is added to preserve old
behavior when desired.

Performance observations on 8K recordsize filesystem:
- 8K random writes at 1-64 threads, up to 60% improvement for one thread
  and smaller gains as thread count increases. At >64 threads, 2-5%
  decrease in performance was observed.
- 8K sequential writes, similar 60% improvement for one thread and
  leveling out around 64 threads. At >64 threads, 5-10% decrease in
  performance was observed.
- 128K sequential write sees 1-5 for the 128K. No observed regression at
  high thread count.

Testing done on Ubuntu 18.04 with 4.15 kernel, 8vCPUs and SSD storage on
VMware ESX.

Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Signed-off-by: Tony Nguyen <tony.nguyen@delphix.com>
Closes #9217
2019-08-28 14:56:54 -07:00
Don Brady
28c91ab66d Tag ABD pages for exclusion in kernel crash dumps
Tag the ABD data pages so that they can be identified for exclusion 
from kernel crash dumps. Eliminating the zfs file data allows for 
significantly smaller crash dump files. Note that ZFS in illumos has 
always excluded the zfs data pages from a kernel crash dump.

This change tags ARC scatter data pages so they can be identified from 
the makedumpfile(8) command. That command is used to create smaller 
dump files by ignoring some memory regions and using compression. It 
already filters file data from the VFS page cache and will now be able 
to exclude ZFS file data pages from the dump file.

A corresponding change to makeumpfile(8) is required to identify ZFS 
data pages.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes #8899
2019-08-28 10:44:46 -07:00
Chunwei Chen
035e96118b Fix zil replay panic when TX_REMOVE followed by TX_CREATE
If TX_REMOVE is followed by TX_CREATE on the same object id, we need to
make sure the object removal is completely finished before creation. The
current implementation relies on dnode_hold_impl with
DNODE_MUST_BE_ALLOCATED returning ENOENT. While this check seems to work
fine before, in current version it does not guarantee the object removal
is completed.

We fix this by checking if DNODE_MUST_BE_FREE returns successful
instead. Also add test and remove dead code in dnode_hold_impl.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes #7151
Closes #8910
Closes #9123
Closes #9145
2019-08-28 10:42:02 -07:00
Andriy Gapon
e6203d288a zfs_ioc_snapshot: check user-prop permissions on snapshotted datasets
Previously, the permissions were checked on the pool which was obviously
incorrect.

After this change, zfs_check_userprops() only validates the properties
without any permission checks.  The permissions are checked individually
for each snapshotted dataset.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Signed-off-by: Andriy Gapon <avg@FreeBSD.org>
Closes #9179 
Closes #9180
2019-08-27 13:45:53 -07:00
Tom Caputi
e7a2fa70c3 Fix deadlock in 'zfs rollback'
Currently, the 'zfs rollback' code can end up deadlocked due to
the way the kernel handles unreferenced inodes on a suspended fs.
Essentially, the zfs_resume_fs() code path may cause zfs to spawn
new threads as it reinstantiates the suspended fs's zil. When a
new thread is spawned, the kernel may attempt to free memory for
that thread by freeing some unreferenced inodes. If it happens to
select inodes that are a a part of the suspended fs a deadlock
will occur because freeing inodes requires holding the fs's
z_teardown_inactive_lock which is still held from the suspend.

This patch corrects this issue by adding an additional reference
to all inodes that are still present when a suspend is initiated.
This prevents them from being freed by the kernel for any reason.

Reviewed-by: Alek Pinchuk <apinchuk@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #9203
2019-08-27 09:55:51 -07:00
Tony Hutter
a9ebdfdd43 Linux 5.3: Fix switch() fall though compiler errors
Fix some switch() fall-though compiler errors:

    abd.c:1504:9: error: this statement may fall through

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #9170
2019-08-21 09:29:23 -07:00
Matthew Ahrens
325d288c5d Add fast path for zfs_ioc_space_snaps() handling of empty_bpobj
When there are many snapshots, calls to zfs_ioc_space_snaps() (e.g. from
`zfs destroy -nv pool/fs@snap1%snap10000`) can be very slow, resulting
in poor performance because we are holding the dp_config_rwlock the
entire time, blocking spa_sync() from continuing.  With around ten
thousand snapshots, we've seen up to 500 seconds in this ioctl,
iterating over up to 50,000,000 bpobjs, ~99% of which are the empty
bpobj.

By creating a fast path for zfs_ioc_space_snaps() handling of the
empty_bpobj, we can achieve a ~5x performance improvement of this ioctl
(when there are many snapshots, and the deadlist is mostly
empty_bpobj's).

Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
External-issue: DLPX-58348
Closes #8744
2019-08-20 11:34:52 -07:00
jdike
3beb0a7694 Fix lockdep circular locking false positive involving sa_lock
There are two different deadlock scenarios, but they share a common
link, which is
thread 1 holding sa_lock and trying to get zap->zap_rwlock:
    zap_lockdir_impl+0x858/0x16c0 [zfs]
    zap_lockdir+0xd2/0x100 [zfs]
    zap_lookup_norm+0x7f/0x100 [zfs]
    zap_lookup+0x12/0x20 [zfs]
    sa_setup+0x902/0x1380 [zfs]
    zfsvfs_init+0x3d6/0xb20 [zfs]
    zfsvfs_create+0x5dd/0x900 [zfs]
    zfs_domount+0xa3/0xe20 [zfs]

and thread 2 trying to get sa_lock, either in sa_setup:
   sa_setup+0x742/0x1380 [zfs]
   zfsvfs_init+0x3d6/0xb20 [zfs]
   zfsvfs_create+0x5dd/0x900 [zfs]
   zfs_domount+0xa3/0xe20 [zfs]
or in sa_build_index:
   sa_build_index+0x13d/0x790 [zfs]
   sa_handle_get_from_db+0x368/0x500 [zfs]
   zfs_znode_sa_init.isra.0+0x24b/0x330 [zfs]
   zfs_znode_alloc+0x3da/0x1a40 [zfs]
   zfs_zget+0x39a/0x6e0 [zfs]
   zfs_root+0x101/0x160 [zfs]
   zfs_domount+0x91f/0xea0 [zfs]

From there, there are different locking paths back to something
holding zap->zap_rwlock.

The deadlock scenarios involve multiple different ZFS filesystems
being mounted.  sa_lock is common to these scenarios, and the sa
struct involved is private to a mount.  Therefore, these must be
referring to different sa_lock instances and these deadlocks can't
occur in practice.

The fix, from Brian Behlendorf, is to remove sa_lock from lockdep
coverage by initializing it with MUTEX_NOLOCKDEP.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jeff Dike <jdike@akamai.com>
Closes #9110
2019-08-19 16:04:26 -07:00
Dominic Pearson
ff4b68eedc Linux 5.3 compat: Makefile subdir-m no longer supported
Uses obj-m instead, due to kernel changes.

See LKML: Masahiro Yamada, Tue, 6 Aug 2019 19:03:23 +0900

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Dominic Pearson <dsp@technoanimal.net>
Closes #9169
2019-08-19 15:22:52 -07:00
Paul Dagnelie
f09fda5071 Cap metaslab memory usage
On systems with large amounts of storage and high fragmentation, a huge 
amount of space can be used by storing metaslab range trees. Since 
metaslabs are only unloaded during a txg sync, and only if they have 
been inactive for 8 txgs, it is possible to get into a state where all 
of the system's memory is consumed by range trees and metaslabs, and 
txgs cannot sync. While ZFS knows how to evict ARC data when needed, 
it has no such mechanism for range tree data. This can result in boot 
hangs for some system configurations.

First, we add the ability to unload metaslabs outside of syncing 
context. Second, we store a multilist of all loaded metaslabs, sorted 
by their selection txg, so we can quickly identify the oldest 
metaslabs.  We use a multilist to reduce lock contention during heavy 
write workloads. Finally, we add logic that will unload a metaslab 
when we're loading a new metaslab, if we're using more than a certain 
fraction of the available memory on range trees.

Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #9128
2019-08-16 09:08:21 -06:00
Serapheim Dimitropoulos
0f8ff49eb6 dmu_tx_wait() hang likely due to cv_signal() in dsl_pool_dirty_delta()
Even though the bug's writeup (Github issue #9136) is very detailed,
we still don't know exactly how we got to that state, thus I wasn't
able to reproduce the bug. That said, we can make an educated guess
combining the information on filled issue with the code.

From the fact that `dp_dirty_total` was 0 (which is less than
`zfs_dirty_data_max`) we know that there was one thread that set it to
0 and then signaled one of the waiters of `dp_spaceavail_cv` [see
`dsl_pool_dirty_delta()` which is also the only place that
`dp_dirty_total` is changed].  Thus, the only logical explaination
then for the bug being hit is that the waiter that just got awaken
didn't go through `dsl_pool_dirty_data()`. Given that this function
is only called by `dsl_pool_dirty_space()` or `dsl_pool_undirty_space()`
I can only think of two possible ways of the above scenario happening:

[1] The waiter didn't call into any of the two functions - which I
    find highly unlikely (i.e. why wait on `dp_spaceavail_cv` to begin
    with?).
[2] The waiter did call in one of the above function but it passed 0 as
    the space/delta to be dirtied (or undirtied) and then the callee
    returned immediately (e.g both `dsl_pool_dirty_space()` and
    `dsl_pool_undirty_space()` return immediately when space is 0).

In any case and no matter how we got there, the easy fix would be to
just broadcast to all waiters whenever `dp_dirty_total` hits 0. That
said and given that we've never hit this before, it would make sense
to think more on why the above situation occured.

Attempting to mimic what Prakash was doing in the issue filed, I
created a dataset with `sync=always` and started doing contiguous
writes in a file within that dataset. I observed with DTrace that even
though we update the pool's dirty data accounting when we would dirty
stuff, the accounting wouldn't be decremented incrementally as we were
done with the ZIOs of those writes (the reason being that
`dbuf_write_physdone()` isn't be called as we go through the override
code paths, and thus `dsl_pool_undirty_space()` is never called). As a
result we'd have to wait until we get to `dsl_pool_sync()` where we
zero out all dirty data accounting for the pool and the current TXG's
metadata.

In addition, as Matt noted and I later verified, the same issue would
arise when using dedup.

In both cases (sync & dedup) we shouldn't have to wait until
`dsl_pool_sync()` zeros out the accounting data. According to the
comment in that part of the code, the reasons why we do the zeroing,
have nothing to do with what we observe:
````
/*
 * We have written all of the accounted dirty data, so our
 * dp_space_towrite should now be zero.  However, some seldom-used
 * code paths do not adhere to this (e.g. dbuf_undirty(), also
 * rounding error in dbuf_write_physdone).
 * Shore up the accounting of any dirtied space now.
 */
dsl_pool_undirty_space(dp, dp->dp_dirty_pertxg[txg & TXG_MASK], txg);
````

Ideally what we want to do is to undirty in the accounting exactly what
we dirty (I use the word ideally as we can still have rounding errors).
This would make the behavior of the system more clear and predictable.

Another interesting issue that I observed with DTrace was that we
wouldn't update any of the pool's dirty data accounting whenever we
would dirty and/or undirty MOS data. In addition, every time we would
change the size of a dbuf through `dbuf_new_size()` we wouldn't update
the accounted space dirtied in the appropriate dirty record, so when
ZIOs are done we would undirty less that we dirtied from the pool's
accounting point of view.

For the first two issues observed (sync & dedup) this patch ensures
that we still update the pool's accounting when we undirty data,
regardless of the write being physical or not.

For changes in the MOS, we first ensure to zero out the pool's dirty
data accounting in `dsl_pool_sync()` after we synced the MOS. Then we
can go ahead and enable the update of the pool's dirty data accounting
wheneve we change MOS data.

Another fix is that we now update the accounting explicitly for
counting errors in `dbuf_write_done()`.

Finally, `dbuf_new_size()` updates the accounted space of the
appropriate dirty record correctly now.

The problem is that we still don't know how the bug came up in the
issue filled. That said the issues fixed seem to be very relevant, so
instead of going with the broadcasting solution right away,
I decided to leave this patch as is.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
External-issue: DLPX-47285
Closes #9137
2019-08-15 17:53:53 -06:00
Tony Nguyen
c8bbf7c00b Improve write performance by using dmu_read_by_dnode()
In zfs_log_write(), we can use dmu_read_by_dnode() rather than
dmu_read() thus avoiding unnecessary dnode_hold() calls.

We get a 2-5% performance gain for large sequential_writes tests, >=128K
writes to files with recordsize=8K.

Testing done on Ubuntu 18.04 with 4.15 kernel, 8vCPUs and SSD storage on
VMware ESX.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Nguyen <tony.nguyen@delphix.com>
Closes #9156
2019-08-15 17:36:24 -06:00
Serapheim Dimitropoulos
0e37a0f4f3 Assert that a dnode's bonuslen never exceeds its recorded size
This patch introduces an assertion that can catch pitfalls in
development where there is a mismatch between the size of
reads and writes between a *_phys structure and its respective
in-core structure when bonus buffers are used.

This debugging-aid should be complementary to the verification
done by ztest in ztest_verify_dnode_bt().

A side to this patch is that we now clear out any extra bytes
past a bonus buffer's new size when the buffer is shrinking.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #8348
2019-08-15 08:44:57 -06:00
Paul Zuchowski
e2b31b58e8 Make txg_wait_synced conditional in zfsvfs_teardown
The call to txg_wait_synced in zfsvfs_teardown should
be made conditional on the objset having dirty data.
This can prevent unnecessary txg_wait_synced during
some unmount operations.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Zuchowski <pzuchowski@datto.com>
Closes #9115
2019-08-15 08:27:13 -06:00
Paul Dagnelie
dc04a8c757 Prevent race in blkptr_verify against device removal
When we check the vdev of the blkptr in zfs_blkptr_verify, we can run 
into a race condition where that vdev is temporarily unavailable. This 
happens when a device removal operation and the old vdev_t has been 
removed from the array, but the new indirect vdev has not yet been 
inserted.

We hold the spa_config_lock while doing our sensitive verification. 
To ensure that we don't deadlock, we only grab the lock if we don't 
have config_writer held. In addition, I had to const the tags of the 
refcounts and the spa_config_lock arguments.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #9112
2019-08-13 21:24:43 -06:00
Chunwei Chen
8e556c5ebc Fix out-of-order ZIL txtype lost on hardlinked files
We should only call zil_remove_async when an object is removed. However,
in current implementation, it is called whenever TX_REMOVE is called. In
the case of hardlinked file, every unlink will generate TX_REMOVE and
causing operations to be dropped even when the object is not removed.

We fix this by only calling zil_remove_async when the file is fully
unlinked.

Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes #8769
Closes #9061
2019-08-13 21:21:27 -06:00
Allan Jude
d2a32912b9 Mark dsl_livelist_should_disable() static
This function is not used outside of dsl_dataset.c

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed by: Sara Hartse <sara.hartse@delphix.com>
Signed-off-by: Allan Jude <allanjude@freebsd.org>
Closes #9154
2019-08-13 21:16:23 -06:00
George Wilson
c8242a96ba spa_load_verify() may consume too much memory
When a pool is imported it will scan the pool to verify the integrity 
of the data and metadata. The amount it scans will depend on the 
import flags provided. On systems with small amounts of memory or 
when importing a pool from the crash kernel, it's possible for 
spa_load_verify to issue too many I/Os that it consumes all the memory 
of the system resulting in an OOM message or a hang.

To prevent this, we limit the amount of memory that the initial pool
scan can consume. This change will, by default, use 1/16th of the ARC
for scan I/Os to prevent running the system out of memory during import.

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: George Wilson george.wilson@delphix.com
External-issue: DLPX-65237
External-issue: DLPX-65238
Closes #9146
2019-08-13 08:11:57 -06:00
Tomohiro Kusumi
a43570c5f3 Change boolean-like uint8_t fields in znode_t to boolean_t
Given znode_t is an in-core structure, it's more readable to have
them as boolean. Also co-locate existing boolean fields with them
for space efficiency (expecting 8 booleans to be packed/aligned).

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #9092
2019-08-13 07:58:02 -06:00
Richard Yao
fccbd1d6e2 Drop KMC_NOEMERGENCY
This is not implemented. If it were implemented, using it would risk
deadlocks on pre-3.18 kernels. Lets just drop it.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Closes #9119
2019-08-13 07:46:12 -06:00
Serapheim Dimitropoulos
3b9edd7b17 Introduce getting holds and listing bookmarks through ZCP
Consumers of ZFS Channel Programs can now list bookmarks,
and get holds from datasets. A minor-refactoring was also
applied to distinguish between user and system properties
in ZCP.

Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Ported-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: Dan Kimmel <dan.kimmel@delphix.com>

OpenZFS-issue: https://illumos.org/issues/8862
Closes #7902
2019-08-12 10:02:34 -07:00
Serapheim Dimitropoulos
2081db7982 Sort log spacemap tunables in alphabetical order
Beside the whole commit being a nit in reality it should
bring the diffs of the spa_log_spacemap.c source file
between ZoL and delphix/zfs to 0.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Chris Dunlop <chris@onthe.net.au>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #9143
2019-08-12 09:49:07 -07:00
Paul Dagnelie
c81f1790e2 Metaslab max_size should be persisted while unloaded
When we unload metaslabs today in ZFS, the cached max_size value is
discarded. We instead use the histogram to determine whether or not we
think we can satisfy an allocation from the metaslab. This can result in
situations where, if we're doing I/Os of a size not aligned to a
histogram bucket, a metaslab is loaded even though it cannot satisfy the
allocation we think it can. For example, a metaslab with 16 entries in
the 16k-32k bucket may have entirely 16kB entries. If we try to allocate
a 24kB buffer, we will load that metaslab because we think it should be
able to handle the allocation. Doing so is expensive in CPU time, disk
reads, and average IO latency. This is exacerbated if the write being
attempted is a sync write.

This change makes ZFS cache the max_size after the metaslab is
unloaded. If we ever get a free (or a coalesced group of frees) larger
than the max_size, we will update it. Otherwise, we leave it as is. When
attempting to allocate, we use the max_size as a lower bound, and
respect it unless we are in try_hard. However, we do age the max_size
out at some point, since we expect the actual max_size to increase as we
do more frees. A more sophisticated algorithm here might be helpful, but
this works reasonably well.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #9055
2019-08-05 14:34:27 -07:00
DeHackEd
99e755d653 Don't wakeup unnecessarily in 'zpool events -f'
ZED can prevent CPU's from properly sleeping.

Rather than periodically waking up in the zevents code, just go to sleep and wait for a wakeup.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: DHE <git@dehacked.net>
Closes #9091
2019-08-05 11:35:47 -07:00
jdike
48be0dfba1 lockdep false positive - move txg_kick() outside of ->dp_lock
This fixes a lockdep warning by breaking a link between ->tx_sync_lock
and ->dp_lock.

The deadlock envisioned by lockdep is this:
    thread 1 holds db->db_mtx and tries to get dp->dp_lock:
	dsl_pool_dirty_space+0x70/0x2d0 [zfs]
	dbuf_dirty+0x778/0x31d0 [zfs]

    thread 2 holds bpo->bpo_lock and tries to get db->db_mtx:
        dmu_buf_will_dirty_impl
        dmu_buf_will_dirty+0x6b/0x6c0 [zfs]
        bpobj_iterate_impl+0xbe6/0x1410 [zfs]

    thread 3 holds tx->tx_sync_lock and tries to get bpo->bpo_lock:
        bpobj_space+0x63/0x470 [zfs]
        dsl_scan_active+0x340/0x3d0 [zfs]
        txg_sync_thread+0x3f2/0x1370 [zfs]

    thread 4 holds dp->dp_lock and tries to get tx->tx_sync_lock
       txg_kick+0x61/0x420 [zfs]
       dsl_pool_need_dirty_delay+0x1c7/0x3f0 [zfs]

This patch is orginally from Brian Behlendorf and slightly simplified
by me.

It breaks this cycle in thread 4 by moving the call from
dsl_pool_need_dirty_delay to txg_kick outside the section controlled
by dp->dp_lock.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Signed-off-by: Jeff Dike <jdike@akamai.com>
Closes #9094
2019-07-31 14:53:39 -07:00
Serapheim Dimitropoulos
1ba4f3e7b4 9072 handle error of zap_cursor_retrieve() for log spacemap zap
In spa_ld_log_sm_metadata(), it is possible for zap_cursor_retrieve()
to return errors other than the expected ENOENT (e.g. when we are at
the end of the zap). Ensure that these error cases are handled
correctly by the import path.

Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Sara Hartse <sara.hartse@delphix.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #9074
2019-07-30 13:20:01 -07:00
Serapheim Dimitropoulos
2fcf4481a6 mismerged log spacemap comment for metaslab_verify_weight_and_frag
When the log spacemap commit was merged in ZoL, the
metaslab_verify_unflushed_changes() debugging function
was deleted as the feature was pretty much stable by
then. Unfortunately though there was a reference to
it from a comment in metaslab_verify_weight_and_frag().

This patch deletes the reference and pastes that
comment as is.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #9097
2019-07-30 10:13:44 -07:00
Matthew Ahrens
0eb8ba6ab6 Improve performance by using dmu_tx_hold_*_by_dnode()
In zfs_write() and dmu_tx_hold_sa(), we can use dmu_tx_hold_*_by_dnode()
instead of dmu_tx_hold_*(), since we already have a dbuf from the target
dnode in hand.  This eliminates some calls to dnode_hold(), which can be
expensive.  This is especially impactful if several threads are
accessing objects that are in the same block of dnodes, because they
will contend for that dbuf's lock.

We are seeing 10-20% performance wins for the sequential_writes tests in
the performance test suite, when doing >=128K writes to files with
recordsize=8K.

This also removes some unnecessary casts that are in the area.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #9081
2019-07-30 09:18:30 -07:00
Brian Behlendorf
adf495e239
Fix channel programs on s390x
When adapting the original sources for s390x the JMP_BUF_CNT was
mistakenly halved due to an incorrect assumption of the size of
a unsigned long.  They are 8 bytes for the s390x architecture.
Increase JMP_BUF_CNT accordingly.

Authored-by: Don Brady <don.brady@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reported-by: Colin Ian King <canonical.com>
Tested-by: Colin Ian King <canonical.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8992
Closes #9080
2019-07-28 18:15:26 -07:00
Tomohiro Kusumi
9fb6abe5ad Implement secpolicy_vnode_setid_retain()
Don't unconditionally return 0 (i.e. retain SUID/SGID).
Test CAP_FSETID capability.

https://github.com/pjd/pjdfstest/blob/master/tests/chmod/12.t
which expects SUID/SGID to be dropped on write(2) by non-owner fails
without this. Most filesystems make this decision within VFS by using
a generic file write for fops.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #9035 
Closes #9043
2019-07-26 13:52:30 -07:00
Sara Hartse
37f03da8ba Fast Clone Deletion
Deleting a clone requires finding blocks are clone-only, not shared
with the snapshot. This was done by traversing the entire block tree
which results in a large performance penalty for sparsely
written clones.

This is new method keeps track of clone blocks when they are
modified in a "Livelist" so that, when it’s time to delete,
the clone-specific blocks are already at hand.

We see performance improvements because now deletion work is
proportional to the number of clone-modified blocks, not the size
of the original dataset.

Reviewed-by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: Sara Hartse <sara.hartse@delphix.com>
Closes #8416
2019-07-26 10:54:14 -07:00
Tomohiro Kusumi
d274ac5460 Don't directly cast unsigned long to void*
Cast to uintptr_t first for portability on integer to/from pointer
conversion.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #9065
2019-07-25 11:59:20 -07:00
Matthew Ahrens
1ff46825e2 Replace zf_rwlock with a mutex
The rwlock implementation on linux does not perform as well as mutexes.
We can realize a performance benefit by replacing the zf_rwlock with a
mutex.  Local microbenchmarks show ~50% improvement, and over NFS we see
~5% improvement on several of the ZFS Performance Tests cases,
especially randwrite and seq_write.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #9062
2019-07-25 11:57:58 -07:00
Tomohiro Kusumi
09276fde1c Fix module_param() type for zfs_read_chunk_size
zfs_read_chunk_size is unsigned long.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #9051
2019-07-19 11:23:56 -07:00
Serapheim Dimitropoulos
7f31908913 Tricky semantics of ms_max_size in metaslab_should_allocate()
metaslab_should_allocate() is used in two places:
[1] When trying to select a metaslab to allocate from
[2] When trying to allocate from a metaslab

In [2] we always expect the metaslab to be loaded, and after
the refactoring of the log spacemap changes, whenever we load
a metaslab we set ms_max_size to the biggest range in the
ms_allocatable tree. Thus, when it is used in [2], if that
field is 0, it means that the metaslab doesn't have any
segments that can be used for allocations now (though it may
have some free space but that space can be in the freeing,
freed, or deferred trees).

In [1] a metaslab can be loaded or unloaded at which point 0
can either mean the metaslab doesn't have any space or the
metaslab is just not loaded thus we go ahead and try to make
an estimation based on its weight.

The issue here is when we call the above function for [2] and
the metaslab doesn't have any allocatable space, we still go
ahead and check its ms_weight which may be out of date because
we haven't ran metaslab_sync_done() yet. At that point we are
allowing an allocation to be attempted even though we know
there is no range that is allocatable.

This patch fixes this issue by explicitly checking if the
metaslab is loaded and if it is, the ms_max_size is used.

Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #9045
2019-07-19 11:19:50 -07:00
Serapheim Dimitropoulos
43a8536260 Race condition between spa async threads and export
In the past we've seen multiple race conditions that have
to do with open-context threads async threads and concurrent
calls to spa_export()/spa_destroy() (including the one
referenced in issue #9015).

This patch ensures that only one thread can execute the
main body of spa_export_common() at a time, with subsequent
threads returning with a new error code created just for
this situation, eliminating this way any race condition
bugs introduced by concurrent calls to this function.

Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #9015 
Closes #9044
2019-07-18 13:02:33 -07:00
Serapheim Dimitropoulos
1c44a5c97f hdr_recl calls zthr_wakeup() on destroyed zthr
There exists a race condition were hdr_recl() calls
zthr_wakeup() on a destroyed zthr. The timeline is the
following:

[1] hdr_recl() runs first and goes intro zthr_wakeup()
    because arc_initialized is set.
[2] arc_fini() is called by another thread, zeroes
    that flag, destroying the zthr, and goes into
    buf_init().
[3] hdr_recl() tries to enter the destroyed mutex
    and we blow up.

This patch ensures that the ARC's zthrs are not offloaded
any new work once arc_initialized is set and then destroys
them after all of the ARC state has been deleted.

Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #9047
2019-07-18 12:55:29 -07:00
Tomohiro Kusumi
f79121d114 Fix wrong comment on zcr_blksz_{min,max}
These aren't tunable; illumos has this comment fixed in
"3742 zfs comments need cleaner, more consistent style",
so sync with that.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #9052
2019-07-18 12:48:46 -07:00
Brian Behlendorf
d64dd3b62a Retire unused spl_{mutex,rwlock}_{init_fini}
These functions are unused and can be removed along
with the spl-mutex.c and spl-rwlock.c source files.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9029
2019-07-17 15:13:53 -07:00
Brian Behlendorf
e7a99dab2b Linux 5.3 compat: retire rw_tryupgrade()
The Linux kernel's rwsem's have never provided an interface to
allow a reader to be upgraded to a writer.  Historically, this
functionality has been implemented by a SPL wrapper function.
However, this approach depends on internal knowledge of the
rw_semaphore and is therefore rather brittle.

Since the ZFS code must always be able to fallback to rw_exit()
and rw_enter() when an rw_tryupgrade() fails; this functionality
isn't critical.  Furthermore, the only potentially performance
sensitive consumer is dmu_zfetch() and no decrease in performance
was observed with this change applied.  See the PR comments for
additional testing details.

Therefore, it is being retired to make the build more robust and
to simplify the rwlock implementation.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9029
2019-07-17 15:08:56 -07:00
Brian Behlendorf
041205afee Linux 5.3 compat: rw_semaphore owner
Commit https://github.com/torvalds/linux/commit/94a9717b updated the
rwsem's owner field to contain additional flags describing the rwsem's
state.  Rather then update the wrappers to mask out these bits, the
code no longer relies on the owner stored by the kernel.  This does
increase the size of a krwlock_t but it makes the implementation
less sensitive to future kernel changes.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9029
2019-07-17 15:07:46 -07:00
jdike
a649768a17 Fix lockdep recursive locking false positive in dbuf_destroy
lockdep reports a possible recursive lock in dbuf_destroy.

It is true that dbuf_destroy is acquiring the dn_dbufs_mtx
on one dnode while holding it on another dnode.  However,
it is impossible for these to be the same dnode because,
among other things,dbuf_destroy checks MUTEX_HELD before
acquiring the mutex.

This fix defines a class NESTED_SINGLE == 1 and changes
that lock to call mutex_enter_nested with a subclass of
NESTED_SINGLE.

In order to make the userspace code compile,
include/sys/zfs_context.h now defines mutex_enter_nested and
NESTED_SINGLE.

This is the lockdep report:

[  122.950921] ============================================
[  122.950921] WARNING: possible recursive locking detected
[  122.950921] 4.19.29-4.19.0-debug-d69edad5368c1166 #1 Tainted: G           O
[  122.950921] --------------------------------------------
[  122.950921] dbu_evict/1457 is trying to acquire lock:
[  122.950921] 0000000083e9cbcf (&dn->dn_dbufs_mtx){+.+.}, at: dbuf_destroy+0x3c0/0xdb0 [zfs]
[  122.950921]
               but task is already holding lock:
[  122.950921] 0000000055523987 (&dn->dn_dbufs_mtx){+.+.}, at: dnode_evict_dbufs+0x90/0x740 [zfs]
[  122.950921]
               other info that might help us debug this:
[  122.950921]  Possible unsafe locking scenario:

[  122.950921]        CPU0
[  122.950921]        ----
[  122.950921]   lock(&dn->dn_dbufs_mtx);
[  122.950921]   lock(&dn->dn_dbufs_mtx);
[  122.950921]
                *** DEADLOCK ***

[  122.950921]  May be due to missing lock nesting notation

[  122.950921] 1 lock held by dbu_evict/1457:
[  122.950921]  #0: 0000000055523987 (&dn->dn_dbufs_mtx){+.+.}, at: dnode_evict_dbufs+0x90/0x740 [zfs]
[  122.950921]
               stack backtrace:
[  122.950921] CPU: 0 PID: 1457 Comm: dbu_evict Tainted: G           O      4.19.29-4.19.0-debug-d69edad5368c1166 #1
[  122.950921] Hardware name: Supermicro H8SSL-I2/H8SSL-I2, BIOS 080011  03/13/2009
[  122.950921] Call Trace:
[  122.950921]  dump_stack+0x91/0xeb
[  122.950921]  __lock_acquire+0x2ca7/0x4f10
[  122.950921]  lock_acquire+0x153/0x330
[  122.950921]  dbuf_destroy+0x3c0/0xdb0 [zfs]
[  122.950921]  dbuf_evict_one+0x1cc/0x3d0 [zfs]
[  122.950921]  dbuf_rele_and_unlock+0xb84/0xd60 [zfs]
[  122.950921]  dnode_evict_dbufs+0x3a6/0x740 [zfs]
[  122.950921]  dmu_objset_evict+0x7a/0x500 [zfs]
[  122.950921]  dsl_dataset_evict_async+0x70/0x480 [zfs]
[  122.950921]  taskq_thread+0x979/0x1480 [spl]
[  122.950921]  kthread+0x2e7/0x3e0
[  122.950921]  ret_from_fork+0x27/0x50

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jeff Dike <jdike@akamai.com>
Closes #8984
2019-07-17 09:18:24 -07:00
Michael Niewöhner
5784c7c36e Add missing __GFP_HIGHMEM flag to vmalloc
Make use of __GFP_HIGHMEM flag in vmem_alloc, which is required for
some 32-bit systems to make use of full available memory.
While kernel versions >=4.12-rc1 add this flag implicitly, older
kernels do not.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Closes #9031
2019-07-17 09:09:22 -07:00
Tomohiro Kusumi
c8802ba08d Use zfsctl_snapshot_hold() wrapper
zfs_refcount_*() are to be wrapped by zfsctl_snapshot_*() in this file.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #9039
2019-07-17 09:07:53 -07:00
Brian Behlendorf
8062b7686a
Minor style cleanup
Resolve an assortment of style inconsistencies including
use of white space, typos, capitalization, and line wrapping.
There is no functional change.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9030
2019-07-16 17:22:31 -07:00
Brian Behlendorf
3b03ff2276
Fix get_special_prop() build failure
The cast of the size_t returned by strlcpy() to a uint64_t by the
VERIFY3U can result in a build failure when CONFIG_FORTIFY_SOURCE
is set.  This is due to the additional hardening.  Since the token
is expected to always fit in strval the VERIFY3U has been removed.
If somehow it doesn't, it will still be safely truncated.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Don Brady <don.brady@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #8999
Closes #9020
2019-07-16 14:14:12 -07:00
Serapheim Dimitropoulos
93e28d661e Log Spacemap Project
= Motivation

At Delphix we've seen a lot of customer systems where fragmentation
is over 75% and random writes take a performance hit because a lot
of time is spend on I/Os that update on-disk space accounting metadata.
Specifically, we seen cases where 20% to 40% of sync time is spend
after sync pass 1 and ~30% of the I/Os on the system is spent updating
spacemaps.

The problem is that these pools have existed long enough that we've
touched almost every metaslab at least once, and random writes
scatter frees across all metaslabs every TXG, thus appending to
their spacemaps and resulting in many I/Os. To give an example,
assuming that every VDEV has 200 metaslabs and our writes fit within
a single spacemap block (generally 4K) we have 200 I/Os. Then if we
assume 2 levels of indirection, we need 400 additional I/Os and
since we are talking about metadata for which we keep 2 extra copies
for redundancy we need to triple that number, leading to a total of
1800 I/Os per VDEV every TXG.

We could try and decrease the number of metaslabs so we have less
I/Os per TXG but then each metaslab would cover a wider range on
disk and thus would take more time to be loaded in memory from disk.
In addition, after it's loaded, it's range tree would consume more
memory.

Another idea would be to just increase the spacemap block size
which would allow us to fit more entries within an I/O block
resulting in fewer I/Os per metaslab and a speedup in loading time.
The problem is still that we don't deal with the number of I/Os
going up as the number of metaslabs is increasing and the fact
is that we generally write a lot to a few metaslabs and a little
to the rest of them. Thus, just increasing the block size would
actually waste bandwidth because we won't be utilizing our bigger
block size.

= About this patch

This patch introduces the Log Spacemap project which provides the
solution to the above problem while taking into account all the
aforementioned tradeoffs. The details on how it achieves that can
be found in the references sections below and in the code (see
Big Theory Statement in spa_log_spacemap.c).

Even though the change is fairly constraint within the metaslab
and lower-level SPA codepaths, there is a side-change that is
user-facing. The change is that VDEV IDs from VDEV holes will no
longer be reused. To give some background and reasoning for this,
when a log device is removed and its VDEV structure was replaced
with a hole (or was compacted; if at the end of the vdev array),
its vdev_id could be reused by devices added after that. Now
with the pool-wide space maps recording the vdev ID, this behavior
can cause problems (e.g. is this entry referring to a segment in
the new vdev or the removed log?). Thus, to simplify things the
ID reuse behavior is gone and now vdev IDs for top-level vdevs
are truly unique within a pool.

= Testing

The illumos implementation of this feature has been used internally
for a year and has been in production for ~6 months. For this patch
specifically there don't seem to be any regressions introduced to
ZTS and I have been running zloop for a week without any related
problems.

= Performance Analysis (Linux Specific)

All performance results and analysis for illumos can be found in
the links of the references. Redoing the same experiments in Linux
gave similar results. Below are the specifics of the Linux run.

After the pool reached stable state the percentage of the time
spent in pass 1 per TXG was 64% on average for the stock bits
while the log spacemap bits stayed at 95% during the experiment
(graph: sdimitro.github.io/img/linux-lsm/PercOfSyncInPassOne.png).

Sync times per TXG were 37.6 seconds on average for the stock
bits and 22.7 seconds for the log spacemap bits (related graph:
sdimitro.github.io/img/linux-lsm/SyncTimePerTXG.png). As a result
the log spacemap bits were able to push more TXGs, which is also
the reason why all graphs quantified per TXG have more entries for
the log spacemap bits.

Another interesting aspect in terms of txg syncs is that the stock
bits had 22% of their TXGs reach sync pass 7, 55% reach sync pass 8,
and 20% reach 9. The log space map bits reached sync pass 4 in 79%
of their TXGs, sync pass 7 in 19%, and sync pass 8 at 1%. This
emphasizes the fact that not only we spend less time on metadata
but we also iterate less times to convergence in spa_sync() dirtying
objects.
[related graphs:
stock- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGStock.png
lsm- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGLSM.png]

Finally, the improvement in IOPs that the userland gains from the
change is approximately 40%. There is a consistent win in IOPS as
you can see from the graphs below but the absolute amount of
improvement that the log spacemap gives varies within each minute
interval.
sdimitro.github.io/img/linux-lsm/StockVsLog3Days.png
sdimitro.github.io/img/linux-lsm/StockVsLog10Hours.png

= Porting to Other Platforms

For people that want to port this commit to other platforms below
is a list of ZoL commits that this patch depends on:

Make zdb results for checkpoint tests consistent
db587941c5

Update vdev_is_spacemap_addressable() for new spacemap encoding
419ba59145

Simplify spa_sync by breaking it up to smaller functions
8dc2197b7b

Factor metaslab_load_wait() in metaslab_load()
b194fab0fb

Rename range_tree_verify to range_tree_verify_not_present
df72b8bebe

Change target size of metaslabs from 256GB to 16GB
c853f382db

zdb -L should skip leak detection altogether
21e7cf5da8

vs_alloc can underflow in L2ARC vdevs
7558997d2f

Simplify log vdev removal code
6c926f426a

Get rid of space_map_update() for ms_synced_length
425d3237ee

Introduce auxiliary metaslab histograms
928e8ad47d

Error path in metaslab_load_impl() forgets to drop ms_sync_lock
8eef997679

= References

Background, Motivation, and Internals of the Feature
- OpenZFS 2017 Presentation:
youtu.be/jj2IxRkl5bQ
- Slides:
slideshare.net/SerapheimNikolaosDim/zfs-log-spacemaps-project

Flushing Algorithm Internals & Performance Results
(Illumos Specific)
- Blogpost:
sdimitro.github.io/post/zfs-lsm-flushing/
- OpenZFS 2018 Presentation:
youtu.be/x6D2dHRjkxw
- Slides:
slideshare.net/SerapheimNikolaosDim/zfs-log-spacemap-flushing-algorithm

Upstream Delphix Issues:
DLPX-51539, DLPX-59659, DLPX-57783, DLPX-61438, DLPX-41227, DLPX-59320
DLPX-63385

Reviewed-by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #8442
2019-07-16 10:11:49 -07:00
Tomohiro Kusumi
6993e01202 Drop redundant POSIX ACL check in zpl_init_acl()
ZFS_ACLTYPE_POSIXACL has already been tested in zpl_init_acl(),
so no need to test again on POSIX ACL access.

Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #9009
2019-07-15 16:26:52 -07:00
Brian Behlendorf
64f3d39ae4
Export dnode symbols
External consumers such as Lustre require access to the dnode
interfaces in order to correctly manipulate dnodes.

Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #8994
Closes #9027
2019-07-15 16:11:55 -07:00
Tom Caputi
9949b856a0 Ensure dsl_destroy_head() decrypts objsets
This patch corrects a small issue where the dsl_destroy_head()
code that runs when the async_destroy feature is disabled would
not properly decrypt the dataset before beginning processing.
If the dataset is not able to be decrypted, the optimization
code now simply does not run and the dataset is completely
destroyed in the DSL sync task.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #9021
2019-07-15 16:08:42 -07:00
Tomohiro Kusumi
ff9630d1a8 Disable unused pathname::pn_path* (unneeded in Linux)
struct pathname is originally from Solaris VFS, and it has been used
in ZoL to merely call VOP from Linux VFS interface without API change,
therefore pathname::pn_path* are unused and unneeded. Technically,
struct pathname is a wrapper for C string in ZoL.

Saves stack a bit on lookup and unlink.

(#if0'd members instead of removing since comments refer to them.)

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #9025
2019-07-15 13:57:56 -07:00
Brian Behlendorf
e5db313494
Linux 5.0 compat: SIMD compatibility
Restore the SIMD optimization for 4.19.38 LTS, 4.14.120 LTS,
and 5.0 and newer kernels.  This is accomplished by leveraging
the fact that by definition dedicated kernel threads never need
to concern themselves with saving and restoring the user FPU state.
Therefore, they may use the FPU as long as we can guarantee user
tasks always restore their FPU state before context switching back
to user space.

For the 5.0 and 5.1 kernels disabling preemption and local
interrupts is sufficient to allow the FPU to be used.  All non-kernel
threads will restore the preserved user FPU state.

For 5.2 and latter kernels the user FPU state restoration will be
skipped if the kernel determines the registers have not changed.
Therefore, for these kernels we need to perform the additional
step of saving and restoring the FPU registers.  Invalidating the
per-cpu global tracking the FPU state would force a restore but
that functionality is private to the core x86 FPU implementation
and unavailable.

In practice, restricting SIMD to kernel threads is not a major
restriction for ZFS.  The vast majority of SIMD operations are
already performed by the IO pipeline.  The remaining cases are
relatively infrequent and can be handled by the generic code
without significant impact.  The two most noteworthy cases are:

  1) Decrypting the wrapping key for an encrypted dataset,
     i.e. `zfs load-key`.  All other encryption and decryption
     operations will use the SIMD optimized implementations.

  2) Generating the payload checksums for a `zfs send` stream.

In order to avoid making any changes to the higher layers of ZFS
all of the `*_get_ops()` functions were updated to take in to
consideration the calling context.  This allows for the fastest
implementation to be used as appropriate (see kfpu_allowed()).

The only other notable instance of SIMD operations being used
outside a kernel thread was at module load time.  This code
was moved in to a taskq in order to accommodate the new kernel
thread restriction.

Finally, a few other modifications were made in order to further
harden this code and facilitate testing.  They include updating
each implementations operations structure to be declared as a
constant.  And allowing "cycle" to be set when selecting the
preferred ops in the kernel as well as user space.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8754 
Closes #8793 
Closes #8965
2019-07-12 09:31:20 -07:00
Nick Mattis
d230a65c3b Fixes: #8934 Large kmem_alloc
Large allocation over the spl_kmem_alloc_warn value was being performed.
Switched to vmem_alloc interface as specified for large allocations.
Changed the subsequent frees to match.

Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: nmattis <nickm970@gmail.com>
Closes #8934
Closes #9011
2019-07-10 15:54:49 -07:00
Paul Dagnelie
f664f1ee7f Decrease contention on dn_struct_rwlock
Currently, sequential async write workloads spend a lot of time 
contending on the dn_struct_rwlock. This lock is responsible for 
protecting the entire block tree below it; this naturally results 
in some serialization during heavy write workloads. This can be 
resolved by having per-dbuf locking, which will allow multiple 
writers in the same object at the same time.

We introduce a new rwlock, the db_rwlock. This lock is responsible 
for protecting the contents of the dbuf that it is a part of; when 
reading a block pointer from a dbuf, you hold the lock as a reader. 
When writing data to a dbuf, you hold it as a writer. This allows 
multiple threads to write to different parts of a file at the same 
time.

Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Matt Ahrens matt@delphix.com
Reviewed by: George Wilson george.wilson@delphix.com
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
External-issue: DLPX-52564
External-issue: DLPX-53085
External-issue: DLPX-57384
Closes #8946
2019-07-08 13:18:50 -07:00
Brad Lewis
cb70964221 8659 static dtrace probes unavailable on non-GPL modules
ZFS tracing efforts are hampered by the inability to access zfs static
probes(probes using DTRACE_PROBE macros). The probes are available via
tracepoints for GPL modules only.  The build could be modified to
generate a function for each unique DTRACE_PROBE invocation. These could
be then accessed via kprobes.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Signed-off-by: Brad Lewis <brad.lewis@delphix.com>
Closes #8659 
Closes #8663
2019-07-08 11:20:53 -07:00
Brian Behlendorf
1086f54219 Revert "Fail early on bio corruption confirmed on 5.2-rc1"
This reverts commit aa7aab6c45.
The change is not compatible with CentOS 6's 2.6.32 based kernel
due to differnces in the bio layer.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #8961
2019-07-05 20:38:56 -07:00
Tom Caputi
52a83dc694 Remove VERIFY from dsl_dataset_crypt_stats()
This patch fixes an issue where dsl_dataset_crypt_stats() would
VERIFY that it was able to hold the encryption root. This function
should instead silently continue without populating the related
field in the nvlist, as is the convention for this code.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #8976
2019-07-05 16:53:14 -07:00
Paul Dagnelie
fe0ea84812 Don't activate metaslabs with weight 0
We return ENOSPC in metaslab_activate if the metaslab has weight 0, 
to avoid activating a metaslab with no space available.  For sanity 
checking, we also assert that there is no free space in the range 
tree in that case.

Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #8968
2019-07-05 16:45:20 -07:00
Paul Zuchowski
6dbca94f0c Improve "Unable to automount" error message.
Having the mountpoint and dataset name both in the message made it
confusing to read.  Additionally, convert this to a zfs_dbgmsg rather than
sending it to the console.

Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Zuchowski <pzuchowski@datto.com>
Closes #8959
2019-07-03 13:05:02 -07:00
Tomohiro Kusumi
aa7aab6c45 Fail early on bio corruption confirmed on 5.2-rc1
Unable to import zpool with "Large kmem_alloc" warning due to
corrupted bio's with invalid # of page vectors.
See #8867 for details.

Fail early with ENOMEM.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #8867 
Closes #8961
2019-07-03 13:03:22 -07:00
Brian Behlendorf
46db9d6161
Check b_freeze_cksum under ZFS_DEBUG_MODIFY conditional
The b_freeze_cksum field can only have data when ZFS_DEBUG_MODIFY
is set.  Therefore, the EQUIV check must be wrapped accordingly.
For the same reason the ASSERT in arc_buf_fill() in unsafe.
However, since it's largely redundant it has simply been removed.

Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8979
2019-07-03 13:01:54 -07:00
Tomohiro Kusumi
df358db7c3 Don't use d_path() for automount mount point for chroot'd process
Chroot'd process fails to automount snapshots due to realpath(3)
failure in mount.zfs(8).

Construct a mount point path from sb of the ctldir inode and dirent
name, instead of from d_path(), so that chroot'd process doesn't get
affected by its view of fs.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #8903 
Closes #8966
2019-07-02 08:25:23 -07:00
George Wilson
681a85cb01 nopwrites on dmu_sync-ed blocks can result in a panic
After device removal, performing nopwrites on a dmu_sync-ed block
will result in a panic. This panic can show up in two ways:
1. an attempt to issue an IOCTL in vdev_indirect_io_start()
2. a failed comparison of zio->io_bp and zio->io_bp_orig in
   zio_done()
To resolve both of these panics, nopwrites of blocks on indirect
vdevs should be ignored and new allocations should be performed on
concrete vdevs.

Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Don Brady <don.brady@delphix.com>
Signed-off-by: George Wilson <gwilson@delphix.com>
Closes #8957
2019-06-28 12:40:23 -07:00
Paul Dagnelie
679b0f2abf Concurrent small allocation defeats large allocation
With the new parallel allocators scheme, there is a possibility for 
a problem where two threads, allocating from the same allocator at 
the same time, conflict with each other. There are two primary cases 
to worry about. First, another thread working on another allocator
activates the same metaslab that the first thread was trying to
activate. This results in the first thread needing to go back and
reselect a new metaslab, even though it may have waited a long time
for this metaslab to load. Second, another thread working on the same
allocator may have activated a different metaslab while the first
thread was waiting for its metaslab to load. Both of these cases
can cause the first thread to be significantly delayed in issuing 
its IOs. The second case can also cause metaslab load/unload churn; 
because the metaslab is loaded but not fully activated, we never set 
the selected_txg, which results in the metaslab being immediately 
unloaded again. This process can repeat many times, wasting disk and 
cpu resources. This is more likely to happen when the IO of the first 
thread is a larger one (like a ZIL write) and the other thread is 
doing a smaller write, because it is more likely to find an 
acceptable metaslab quickly.

There are two primary changes. The first is to always proceed with 
the allocation when returning from metaslab_activate if we were 
preempted in either of the ways described in the previous section. 
The second change is to set the selected_txg before we do the call 
to activate so that even if the metaslab is not used for an 
allocation, we won't immediately attempt to unload it.

Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
External-issue: DLPX-61314
Closes #8843
2019-06-26 11:00:12 -07:00
Alexander Motin
fc7546777b Avoid extra taskq_dispatch() calls by DMU
DMU sync code calls taskq_dispatch() for each sublist of os_dirty_dnodes
and os_synced_dnodes.  Since the number of sublists by default is equal
to number of CPUs, it will dispatch equal, potentially large, number of
tasks, waking up many CPUs to handle them, even if only one or few of
sublists actually have any work to do.

This change adds check for empty sublists to avoid this.

Reviewed by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:  Alexander Motin <mav@FreeBSD.org>
Closes #8909
2019-06-25 12:03:38 -07:00
loli10K
746d4a451e Fix bp_embedded_type enum definition
With the addition of BP_EMBEDDED_TYPE_REDACTED in 30af21b0 a couple of
codepaths make wrong assumptions and could potentially result in errors.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Chris Dunlop <chris@onthe.net.au>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #8951
2019-06-24 18:02:17 -07:00
Matthew Ahrens
59ec30a329 Remove code for zfs remap
The "zfs remap" command was disabled by
6e91a72fe3, because it has little utility
and introduced some tricky bugs.  This commit removes the code for it,
the associated ZFS_IOC_REMAP ioctl, and tests.

Note that the ioctl and property will remain, but have no functionality.
This allows older software to fail gracefully if it attempts to use
these, and avoids a backwards incompatibility that would be introduced if
we renumbered the later ioctls/props.

Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #8944
2019-06-24 16:44:01 -07:00
Tom Caputi
53864800f6 Fix error message on promoting encrypted dataset
This patch corrects the error message reported when attempting
to promote a dataset outside of its encryption root.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #8905 
Closes #8935
2019-06-24 16:42:52 -07:00