Commit Graph

35 Commits

Author SHA1 Message Date
Serapheim Dimitropoulos c19a6512fd Name anonymous enum of KMC_BIT constants
Giving a name to this enum makes it discoverable from
debugging tools like DRGN and SDB. For example, with
the name proposed on this patch we can iterate over
these values in DRGN:
```
>>> prog.type('enum kmc_bit').enumerators
(('KMC_BIT_NOTOUCH', 0), ('KMC_BIT_NODEBUG', 1),
('KMC_BIT_NOMAGAZINE', 2), ('KMC_BIT_NOHASH', 3),
('KMC_BIT_QCACHE', 4), ('KMC_BIT_KMEM', 5),
('KMC_BIT_VMEM', 6), ('KMC_BIT_SLAB', 7),
...
```
This enables SDB to easily pretty-print the flags of
the spl_kmem_caches in the system like this:
```
> spl_kmem_caches -o "name,flags,total_memory"
name                                       flags total_memory
------------------------ ----------------------- ------------
abd_t                    KMC_NOMAGAZINE|KMC_SLAB        4.5MB
arc_buf_hdr_t_full       KMC_NOMAGAZINE|KMC_SLAB       12.3MB
... <cropped> ...
ddt_cache                               KMC_VMEM      583.7KB
ddt_entry_cache          KMC_NOMAGAZINE|KMC_SLAB         0.0B
... <cropped> ...
zio_buf_1048576             KMC_NODEBUG|KMC_VMEM         0.0B
... <cropped> ...
```

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #9478
2020-01-22 13:49:03 -08:00
Andrea Gelmini bcfa65802c Fix typos in include/
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 #9238
2020-01-22 13:48:59 -08:00
Richard Yao 0b96952eef 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
2020-01-22 13:48:57 -08:00
Don Brady e625030c11 OpenZFS 9425 - channel programs can be interrupted
Problem Statement
=================
ZFS Channel program scripts currently require a timeout, so that hung or
long-running scripts return a timeout error instead of causing ZFS to get
wedged. This limit can currently be set up to 100 million Lua instructions.
Even with a limit in place, it would be desirable to have a sys admin
(support engineer) be able to cancel a script that is taking a long time.

Proposed Solution
=================
Make it possible to abort a channel program by sending an interrupt signal.In
the underlying txg_wait_sync function, switch the cv_wait to a cv_wait_sig to
catch the signal. Once a signal is encountered, the dsl_sync_task function can
install a Lua hook that will get called before the Lua interpreter executes a
new line of code. The dsl_sync_task can resume with a standard txg_wait_sync
call and wait for the txg to complete.  Meanwhile, the hook will abort the
script and indicate that the channel program was canceled. The kernel returns
a EINTR to indicate that the channel program run was canceled.

Porting notes: Added missing return value from cv_wait_sig()

Authored by: Don Brady <don.brady@delphix.com>
Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Sara Hartse <sara.hartse@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Robert Mustacchi <rm@joyent.com>
Ported-by: Don Brady <don.brady@delphix.com>
Signed-off-by: Don Brady <don.brady@delphix.com>

OpenZFS-issue: https://www.illumos.org/issues/9425
OpenZFS-commit: https://github.com/illumos/illumos-gate/commit/d0cb1fb926
Closes #8904
2020-01-22 13:48:56 -08:00
Brian Behlendorf 428a63cc62 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
2019-09-25 11:27:49 -07:00
Brian Behlendorf 3982d959c5 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
2019-09-25 11:27:49 -07:00
Brian Behlendorf 54561073e7 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
2019-09-25 11:27:49 -07:00
jdike 4c98586daf 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
2019-09-25 11:27:49 -07:00
Tomohiro Kusumi 328c95e391 Remove vn_set_fs_pwd()/vn_set_pwd() (no need to be at / during insmod)
Per suggestion from @behlendorf in #8777, remove vn_set_fs_pwd() and
vn_set_pwd() which are only used in zfs_ioctl.c:_init() while loading
zfs.ko.

The rest of initialization functions being called here after cwd set
to / don't depend on cwd of the process except for spa_config_load().
spa_config_load() uses a relative path ".//etc/zfs/zpool.cache" when
`rootdir` is non-NULL, which is "/etc/zfs/zpool.cache" given cwd is /,
so just unconditionally use the absolute path without "./", so that
`vn_set_pwd("/")` as well as the entire functions can be removed.
This is also what FreeBSD does.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@osnexus.com>
Closes #8826
2019-09-25 11:27:46 -07:00
Rafael Kitover e0cd6c28a3 kernel timer API rework
In `config/kernel-timer.m4` refactor slightly to check more generally
for the new `timer_setup()` APIs, but also check the callback signature
because some kernels (notably 4.14) have the new `timer_setup()` API but
use the old callback signature. Also add a check for a `flags` member in
`struct timer_list`, which was added in 4.1-rc8.

Add compatibility shims to `include/spl/sys/timer.h` to allow using the
new timer APIs with the only two caveats being that the callback
argument type must be declared as `spl_timer_list_t` and an explicit
assignment is required to get the timer variable for the `timer_of()`
macro. So the callback would look like this:

```c
__cv_wakeup(spl_timer_list_t t)
{
        struct timer_list *tmr = (struct timer_list *)t;
	struct thing *parent = from_timer(parent, tmr,
		parent_timer_field);
	... /* do stuff with parent */
```

Make some minor changes to `spl-condvar.c` and `spl-taskq.c` to use the
new timer APIs instead of conditional code.

Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rafael Kitover <rkitover@gmail.com>
Closes #8647
2019-09-25 11:27:46 -07:00
loli10K 438275c9a0 VERIFY3P() message is missing a space character
This commit just reintroduces a [space] character inadvertently removed
in a887d653.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #8786
2019-06-07 12:39:13 -07:00
Tomohiro Kusumi 4d7cb872e8 Linux 2.6.39 compat: Test if kstrtoul() exists
kstrtoul() exists only after torvalds/linux@33ee3b2e2e in 2.6.39.
Use strict_strtoul() if kstrtoul() doesn't exist.
Note that strict_strtoul() has existed as an alias for kstrtoul()
for a while, but removed in torvalds/linux@3db2e9cdc0.

It looks like RHEL6 (2.6.32 based) has backported kstrtoul(),
and this caused build CI to pass compilation test.
It should fail on vanilla < 2.6.39 kernels or distro kernels without
backport as reported in #8760.

--
 # grep "kstrtoul(" /lib/modules/2.6.32-754.12.1.el6.x86_64/build/ \
 include/linux/kernel.h >/dev/null
 # echo $?
 0

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #8760 
Closes #8761
2019-06-07 12:39:13 -07:00
Brian Behlendorf bff2361aeb
Linux 5.2 compat: rw_tryupgrade()
Commit torvalds/linux@46ad0840b has removed the architecture specific
rwsem source and headers leaving only the generic version.  As part
of this change the RWSEM_ACTIVE_READ_BIAS and RWSEM_ACTIVE_WRITE_BIAS
macros were moved to the private kernel/locking/rwsem.h header.
This results in a build failure because these macros were required
to implement the rw_tryupgrade() compatibility function.

In practice, this isn't a major problem because there are only a
few consumers of rw_tryupgrade() and because consumers of rw_tryupgrade
should be written to retry using rw_enter(RW_WRITER).

After auditing all of the callers only dmu_zfetch() was determined
not to perform a retry.  It has been updated in this commit to
resolve this issue.

That said, the rw_tryupgrade() functionality should be considered
for possible removal in a future release due to the difficultly
in supporting the interface.

Reviewed-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8730
2019-05-23 13:46:33 -07:00
Tomohiro Kusumi 75346937de Linux 5.1 compat: Drop ULLONG_MAX and LLONG_MAX definitions
Linux kernel commit 54d50897d544c874562253e2a8f70dfcad22afe8
"linux/kernel.h: split *_MAX and *_MIN macros into <linux/limits.h>"

which first appeared in 5.1 has moved several macros from
<linux/kernel.h> to <linux/limits.h>. This broke compilation due to
header inclusion order against the local header include/spl/sys/types.h
which also defines ULLONG_MAX and LLONG_MAX if undefined.

It looks like local ULLONG_MAX and LLONG_MAX were never needed
(or after spl integration ?) as <linux/kernel.h> has had the same
definitions since an upstream commit
111ebb6e6f7bd7de6d722c5848e95621f43700d9 in 2.6.18, so drop them.

--
linux/include/linux/limits.h:17: error: "LLONG_MAX" redefined [-Werror]
 #define LLONG_MAX ((long long)(~0ULL >> 1))
zfs/include/spl/sys/types.h:35: note: this is the location of the previous definition
 #define LLONG_MAX  ((long long)(~0ULL>>1))

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #8714
2019-05-07 09:55:40 -07:00
Tomohiro Kusumi de3e0b914b Linux 5.0 compat: Use totalhigh_pages()
Linux kernel commit ca79b0c211af63fa3276f0e3fd7dd9ada2439839
"mm: convert totalram_pages and totalhigh_pages variables to atomic"

replaced `totalhigh_pages` with an inline function `totalhigh_pages()`.
This broke compilation on IA32, etc, as ZoL uses `totalhigh_pages`
on archs with highmem. Confirmed on Fedora 30 (5.0.9-301.fc30.i686).

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #8677
Closes #8701
2019-05-04 16:40:48 -07:00
Tomohiro Kusumi 9a65234c8b Unbreak build on Linux kernel < 3.10
d12614521a("Fixes for procfs files backed by linked lists")
uses PDE_DATA(), but since PDE_DATA() (public interface which
replaced old public interface PDE()) first appeared in upstream
kernel 3.10, it lacks visible local definition for kernel < 3.10.

Move the local PDE_DATA() definition to a ZoL header, to unbreak
build on kernel < 3.10.

--
module/spl/spl-procfs-list.c: In function 'procfs_list_open':
module/spl/spl-procfs-list.c:166: error: implicit declaration of function 'PDE_DATA'
module/spl/spl-procfs-list.c:166: warning: assignment makes pointer from integer without a cast

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Gallagher <john.gallagher@delphix.com>
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Closes #8599
2019-04-08 14:59:24 -07:00
Sara Hartse a887d653b3 Restrict kstats and print real pointers
There are several places where we use zfs_dbgmsg and %p to
print pointers. In the Linux kernel, these values obfuscated
to prevent information leaks which means the pointers aren't
very useful for debugging crash dumps. We decided to restrict
the permissions of dbgmsg (and some other kstats while we were
at it) and print pointers with %px in zfs_dbgmsg as well as
spl_dumpstack

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Gallagher <john.gallagher@delphix.com>
Signed-off-by: sara hartse <sara.hartse@delphix.com>
Closes #8467 
Closes #8476
2019-04-04 18:57:06 -07:00
Brian Behlendorf 1b939560be
Add TRIM support
UNMAP/TRIM support is a frequently-requested feature to help
prevent performance from degrading on SSDs and on various other
SAN-like storage back-ends.  By issuing UNMAP/TRIM commands for
sectors which are no longer allocated the underlying device can
often more efficiently manage itself.

This TRIM implementation is modeled on the `zpool initialize`
feature which writes a pattern to all unallocated space in the
pool.  The new `zpool trim` command uses the same vdev_xlate()
code to calculate what sectors are unallocated, the same per-
vdev TRIM thread model and locking, and the same basic CLI for
a consistent user experience.  The core difference is that
instead of writing a pattern it will issue UNMAP/TRIM commands
for those extents.

The zio pipeline was updated to accommodate this by adding a new
ZIO_TYPE_TRIM type and associated spa taskq.  This new type makes
is straight forward to add the platform specific TRIM/UNMAP calls
to vdev_disk.c and vdev_file.c.  These new ZIO_TYPE_TRIM zios are
handled largely the same way as ZIO_TYPE_READs or ZIO_TYPE_WRITEs.
This makes it possible to largely avoid changing the pipieline,
one exception is that TRIM zio's may exceed the 16M block size
limit since they contain no data.

In addition to the manual `zpool trim` command, a background
automatic TRIM was added and is controlled by the 'autotrim'
property.  It relies on the exact same infrastructure as the
manual TRIM.  However, instead of relying on the extents in a
metaslab's ms_allocatable range tree, a ms_trim tree is kept
per metaslab.  When 'autotrim=on', ranges added back to the
ms_allocatable tree are also added to the ms_free tree.  The
ms_free tree is then periodically consumed by an autotrim
thread which systematically walks a top level vdev's metaslabs.

Since the automatic TRIM will skip ranges it considers too small
there is value in occasionally running a full `zpool trim`.  This
may occur when the freed blocks are small and not enough time
was allowed to aggregate them.  An automatic TRIM and a manual
`zpool trim` may be run concurrently, in which case the automatic
TRIM will yield to the manual TRIM.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Tim Chase <tim@chase2k.com>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Contributions-by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Contributions-by: Tim Chase <tim@chase2k.com>
Contributions-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8419 
Closes #598
2019-03-29 09:13:20 -07:00
George Wilson 2efea7c82c ZFS Reads may result in unneccesary calls to zil_commit
ZFS supports O_RSYNC for read operations and when specified will ensure
the same level of data integrity that O_DSYNC and O_SYNC provides for
writes. O_RSYNC by itself has no effect so it must be combined with
either O_DSYNC or O_SYNC. However, many platforms don't support O_RSYNC
and have mapped O_SYNC to mean O_RSYNC within ZFS. This is incorrect
and causes unnecessary calls to zil_commit. Only platforms which
support O_RSYNC should implement the zil_commit functionality in the
read code path.

Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Wilson <george.wilson@delphix.com>
Closes #8523
2019-03-22 13:09:11 -07:00
Tony Hutter e73ab1b38c Linux 4.20 compat: Fix VERIFY(RW_READ_HELD(&hash->mh_contents))
The 4.20 kernel changed the meaning of the rw_semaphore.owner bits,
causing an assertion when loading the module under the 4.20 kernel.
This patch fixes the issue.

Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #8360 
Closes #8389
2019-02-15 12:37:20 -08:00
Tony Hutter 031cea17a3 Linux 5.0 compat: Use totalram_pages()
totalram_pages() was converted to an atomic variable in 5.0:

https://patchwork.kernel.org/patch/10652795/

Its value should now be read though the totalram_pages() helper
function.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #8263
2019-01-28 10:11:14 -08:00
Tony Hutter 5cb46f6a66 Linux 4.18 compat: Use ktime_get_coarse_real_ts64()
Newer kernels remove current_kernel_time64().  Use
ktime_get_coarse_real_ts64() in its place.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #8258
2019-01-28 10:11:03 -08:00
Brad Lewis 3ec34e5527 OpenZFS 9284 - arc_reclaim_thread has 2 jobs
Following the fix for 9018 (Replace kmem_cache_reap_now() with
kmem_cache_reap_soon), the arc_reclaim_thread() no longer blocks
while reaping.  However, the code is still confusing and error-prone,
because this thread has two responsibilities.  We should instead
separate this into two threads each with their own responsibility:

 1. keep `arc_size` under `arc_c`, by calling `arc_adjust()`, which
    improves `arc_is_overflowing()`

 2. keep enough free memory in the system, by calling
    `arc_kmem_reap_now()` plus `arc_shrink()`, which improves
    `arc_available_memory()`.

Furthermore, we can use the zthr infrastructure to separate the
"should we do something" from "do it" parts of the logic, and
normalize the start up / shut down of the threads.

Authored by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Dan McDonald <danmcd@joyent.com>
Reviewed by: Tim Kordas <tim.kordas@joyent.com>
Reviewed by: Tim Chase <tim@chase2k.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Ported-by:  Brad Lewis <brad.lewis@delphix.com>
Signed-off-by: Brad Lewis <brad.lewis@delphix.com>

OpenZFS-issue: https://www.illumos.org/issues/9284
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/de753e34f9
Closes #8165
2018-12-26 13:22:28 -08:00
Brian Behlendorf 82c0a050fc
Linux 4.20 compat: current_kernel_time()
Commit torvalds/linux@976516404 removed the current_kernel_time()
function (and several others).  All callers are expected to use
current_kernel_time64().  Update the gethrestime_sec() wrapper
accordingly.

Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8074
2018-10-31 11:50:42 -05:00
ilbsmart 779a6c0bf6 deadlock between mm_sem and tx assign in zfs_write() and page fault
The bug time sequence:
1. thread #1, `zfs_write` assign a txg "n".
2. In a same process, thread #2, mmap page fault (which means the
   `mm_sem` is hold) occurred, `zfs_dirty_inode` open a txg failed,
   and wait previous txg "n" completed.
3. thread #1 call `uiomove` to write, however page fault is occurred
   in `uiomove`, which means it need `mm_sem`, but `mm_sem` is hold by
   thread #2, so it stuck and can't complete,  then txg "n" will
   not complete.

So thread #1 and thread #2 are deadlocked.

Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Grady Wong <grady.w@xtaotech.com>
Closes #7939
2018-10-16 11:11:24 -07:00
Tony Hutter 3c94dd7b7b Define timestruc_t for Lustre compatibility
Lustre 2.8 (and possibly other versions) are still using timestruc_t,
which was removed in spl-0.7.10 in favor of inode_timespec_t.  Add
in a backwards compatibility #define for timestruc_t so that Lustre
builds.

Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #8014
2018-10-12 11:13:34 -07:00
Matthew Ahrens 4cbde2ecbf Create /proc/sys/kernel/spl/gitrev with git hash
The existing mechanisms for determining what code is running in the
kernel do not always correctly report the git hash.  The versions
reported there do not reflect changes made since `configure` was run
(i.e. incremental builds do not update the version) and they are
misleading if git tags are not set up properly.  This applies to
`modinfo zfs`, `dmesg`, and `/sys/module/zfs/version`.

There are complicated requirements on how the existing version is
generated.  Therefore we are leaving that alone, and adding a new
mechanism to record and retrieve the git hash:
`cat /proc/sys/kernel/spl/gitrev`

The gitrev is re-generated at compile time, when running `make`
(including for incremental builds).  The value is the output of `git
describe` (or "unknown" if not in a git repo or there are uncommitted
changes).

We're also removing /proc/sys/kernel/spl/version, which was never very
useful.

Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Tim Chase <tim@chase2k.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #7931 
Closes #7965
2018-10-08 21:57:02 -07:00
Paul Dagnelie 6e8b268875 Fix ASSERT macros to not over-expand
The code reuse in the definitions of the ASSERT and VERIFY macros result
in expansion of their arguments before they are stringified, which
produces ugly and undesirable output.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #7884
2018-10-03 20:16:45 -07:00
John Gallagher d12614521a Fixes for procfs files backed by linked lists
There are some issues with the way the seq_file interface is implemented
for kstats backed by linked lists (zfs_dbgmsgs and certain per-pool
debugging info):

* We don't account for the fact that seq_file sometimes visits a node
  multiple times, which results in missing messages when read through
  procfs.
* We don't keep separate state for each reader of a file, so concurrent
  readers will receive incorrect results.
* We don't account for the fact that entries may have been removed from
  the list between read syscalls, so reading from these files in procfs
  can cause the system to crash.

This change fixes these issues and adds procfs_list, a wrapper around a
linked list which abstracts away the details of implementing the
seq_file interface for a list and exposing the contents of the list
through procfs.

Reviewed by: Don Brady <don.brady@delphix.com>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: John Gallagher <john.gallagher@delphix.com>
External-issue: LX-1211
Closes #7819
2018-09-26 11:08:12 -07:00
Brian Behlendorf 11d0525cbb
Add rwsem_tryupgrade for 4.9.20-rt16 kernel
The RT rwsem implementation was changed to allow multiple readers
as of the 4.9.20-rt16 patch set.  This results in a build failure
because the existing implementation was forced to directly access
the rwsem structure which has changed.

While this could be accommodated by adding additional compatibility
code.  This patch resolves the build issue by simply assuming the
rwsem can never be upgraded.  This functionality is a performance
optimization and all callers must already handle this case.

Converting the last remaining use of __SPIN_LOCK_UNLOCKED to
spin_lock_init() was additionally required to get a clean build.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #7589
2018-07-30 09:22:30 -07:00
Brian Behlendorf 33a19e0fd9
Fix kernel unaligned access on sparc64
Update the SA_COPY_DATA macro to check if architecture supports
efficient unaligned memory accesses at compile time.  Otherwise
fallback to using the sa_copy_data() function.

The kernel provided CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is
used to determine availability in kernel space.  In user space
the x86_64, x86, powerpc, and sometimes arm architectures will
define the HAVE_EFFICIENT_UNALIGNED_ACCESS macro.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #7642 
Closes #7684
2018-07-11 13:10:40 -07:00
Brian Behlendorf 6413c95fbd
Linux 4.18 compat: inode timespec -> timespec64
Commit torvalds/linux@95582b0 changes the inode i_atime, i_mtime,
and i_ctime members form timespec's to timespec64's to make them
2038 safe.  As part of this change the current_time() function was
also updated to return the timespec64 type.

Resolve this issue by introducing a new inode_timespec_t type which
is defined to match the timespec type used by the inode.  It should
be used when working with inode timestamps to ensure matching types.

The timestruc_t type under Illumos was used in a similar fashion but
was specified to always be a timespec_t.  Rather than incorrectly
define this type all timespec_t types have been replaced by the new
inode_timespec_t type.

Finally, the kernel and user space 'sys/time.h' headers were aligned
with each other.  They define as appropriate for the context several
constants as macros and include static inline implementation of
gethrestime(), gethrestime_sec(), and gethrtime().

Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #7643
2018-06-19 21:51:18 -07:00
Tony Hutter f0ed6c7448 Add pool state /proc entry, "SUSPENDED" pools
1. Add a proc entry to display the pool's state:

$ cat /proc/spl/kstat/zfs/tank/state
ONLINE

This is done without using the spa config locks, so it will
never hang.

2. Fix 'zpool status' and 'zpool list -o health' output to print
"SUSPENDED" instead of "ONLINE" for suspended pools.

Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Richard Elling <Richard.Elling@RichardElling.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #7331 
Closes #7563
2018-06-06 09:33:54 -07:00
Brian Behlendorf 93ce2b4ca5 Update build system and packaging
Minimal changes required to integrate the SPL sources in to the
ZFS repository build infrastructure and packaging.

Build system and packaging:
  * Renamed SPL_* autoconf m4 macros to ZFS_*.
  * Removed redundant SPL_* autoconf m4 macros.
  * Updated the RPM spec files to remove SPL package dependency.
  * The zfs package obsoletes the spl package, and the zfs-kmod
    package obsoletes the spl-kmod package.
  * The zfs-kmod-devel* packages were updated to add compatibility
    symlinks under /usr/src/spl-x.y.z until all dependent packages
    can be updated.  They will be removed in a future release.
  * Updated copy-builtin script for in-kernel builds.
  * Updated DKMS package to include the spl.ko.
  * Updated stale AUTHORS file to include all contributors.
  * Updated stale COPYRIGHT and included the SPL as an exception.
  * Renamed README.markdown to README.md
  * Renamed OPENSOLARIS.LICENSE to LICENSE.
  * Renamed DISCLAIMER to NOTICE.

Required code changes:
  * Removed redundant HAVE_SPL macro.
  * Removed _BOOT from nvpairs since it doesn't apply for Linux.
  * Initial header cleanup (removal of empty headers, refactoring).
  * Remove SPL repository clone/build from zimport.sh.
  * Use of DEFINE_RATELIMIT_STATE and DEFINE_SPINLOCK removed due
    to build issues when forcing C99 compilation.
  * Replaced legacy ACCESS_ONCE with READ_ONCE.
  * Include needed headers for `current` and `EXPORT_SYMBOL`.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
TEST_ZIMPORT_SKIP="yes"
Closes #7556
2018-05-29 16:00:33 -07:00
Brian Behlendorf a91258913f Prepare SPL repo to merge with ZFS repo
This commit removes everything from the repository except the core
SPL implementation for Linux.  Those files which remain have been
moved to non-conflicting locations to facilitate the merge.
The README.md and associated files have been updated accordingly.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2018-05-29 14:51:39 -07:00