Commit Graph

5820 Commits

Author SHA1 Message Date
Brian Behlendorf d503b971f4 Optimize spl_rwsem_is_locked()
The spl_rwsem_is_locked() compatibility function has been observed
to be a hot spot.  The root cause of this is that we must check the
rwsem activity under the rwsem->wait_lock to avoid a race.  When
the lock is busy significant contention can occur.

The upstream kernel fix for this race had the insight that by using
spin_trylock_irqsave() this contention could be avoided.  When the
lock is contended it's reasonable to return that it is locked.

This change updates the SPLs implemention to be like the upstream
kernel.  Since the kernel code has been in use for years now this
a low risk change.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-07-13 13:07:39 -07:00
Brian Behlendorf fb7eb3e3e9 Move zfs.release generation to configure step
Previously, the zfs.release file was created at 'make install' time.
This is slightly problematic when the file is needed without running
'make install'. Because of this, the step creating the file was removed
from 'make install' and replaced with a more appropriate zfs.release.in
file.

As a result, the zfs.release file will now be created earlier as part
of the 'configure' step as opposed to the 'make install' step.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-07-12 12:22:51 -07:00
Prakash Surya d801db1487 Move spl.release generation to configure step
Previously, the spl.release file was created at 'make install' time.
This is slightly problematic when the file is needed without running
'make install'. Because of this, the step creating the file was removed
from 'make install' and replaced with a more appropriate spl.release.in
file.

As a result, the spl.release file will now be created earlier as part
of the 'configure' step as opposed to the 'make install' step.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #135
2012-07-12 12:13:47 -07:00
Brian Behlendorf 7535251dcf Add PowerPC to supported VTOCs
This code was was inherited from Solaris which was careful to define
the expected VTOC for various supported architectures.  While this
check may have made sense there it's something we should be able to
safely drop under Linux.

However, I'm not quite ready to do that yet.  So for the moment I'm
just doing the very safe thing of adding PowerPC as a supported type.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-07-12 11:52:34 -07:00
Etienne Dechamps cee43a7477 Fix efi_use_whole_disk() when efi_nparts == 128.
Commit e5dc681a changed EFI_NUMPAR from 9 to 128. This means that the
on-disk EFI label has efi_nparts = 128 instead of 9. The index of the
reserved partition, however, is still 8. This breaks
efi_use_whole_disk(), which uses efi_nparts-1 as the index of the
reserved partition.

This commit fixes efi_use_whole_disk() when the index of the reserved
partition is not efi_nparts-1. It rewrites the algorithm and makes it
more robust by using the order of the partitions instead of their
numbering. It assumes that the last non-empty partition is the reserved
partition, and that the non-empty partition before that is the data
partition.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #808
2012-07-12 08:59:22 -07:00
Etienne Dechamps 7608bd0dd0 Use the right device path when relabeling.
Currently, zpool_vdev_online() calls zpool_relabel_disk() with a short
partition device name, which is obviously wrong because (1)
zpool_relabel_disk() expects a full, absolute path to use with open()
and (2) efi_write() must be called on an opened disk device, not a
partition device.

With this patch, zpool_relabel_disk() gets called with a full disk
device path. The path is determined using the same algorithm as
zpool_find_vdev().

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #808
2012-07-12 08:59:16 -07:00
Etienne Dechamps 8adf486422 Fix error handling for "zpool online -e".
The error handling code around zpool_relabel_disk() is either inexistent
or wrong. The function call itself is not checked, and
zpool_relabel_disk() is generating error messages from an unitialized
buffer.

Before:

    # zpool online -e homez sdb; echo $?
    `: cannot relabel 'sdb1': unable to open device: 2
    0

After:

    # zpool online -e homez sdb; echo $?
    cannot expand sdb: cannot relabel 'sdb1': unable to open device: 2
    1

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #808
2012-07-12 08:58:19 -07:00
George Wilson c7f2d69de3 Illumos #1949, #1953
1949 crash during reguid causes stale config
1953 allow and unallow missing from zpool history since removal of pyzfs

Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Bill Pijewski <wdp@joyent.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Reviewed by: Garrett D'Amore <garrett.damore@gmail.com>
Reviewed by: Dan McDonald <danmcd@nexenta.com>
Reviewed by: Steve Gonczi <gonczi@comcast.net>
Approved by: Eric Schrock <eric.schrock@delphix.com>

References:
  https://www.illumos.org/issues/1949
  https://www.illumos.org/issues/1953

Ported by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #665
2012-07-11 13:33:31 -07:00
Garrett D'Amore 3541dc6d02 Illumos #1748: desire support for reguid in zfs
Reviewed by: George Wilson <gwilson@zfsmail.com>
Reviewed by: Igor Kozhukhov <ikozhukhov@gmail.com>
Reviewed by: Alexander Eremin <alexander.eremin@nexenta.com>
Reviewed by: Alexander Stetsenko <ams@nexenta.com>
Approved by: Richard Lowe <richlowe@richlowe.net>

References:
  https://www.illumos.org/issues/1748

This commit modifies the user to kernel space ioctl ABI.  Extra
care should be taken when updating to ensure both the kernel
modules and utilities are updated.  If only the user space
component is updated both the 'zpool events' command and the
'zpool reguid' command will not work until the kernel modules
are updated.

Ported by:     Martin Matuska <martin@matuska.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #665
2012-07-11 13:08:56 -07:00
Richard Yao 36811b4430 Detect kernels that honor gfp flags passed to vmalloc()
zfsonlinux/spl@2092cf68d8 used
PF_MEMALLOC to workaround a bug in the Linux kernel where
allocations did not honor the gfp flags passed to vmalloc().
Unfortunately, PF_MEMALLOC has the side effect of permitting
allocations to allocate pages outside of ZONE_NORMAL. This
has been observed to result in the depletion of ZONE_DMA32.

A kernel patch is available in the Gentoo bug tracker for
this issue.

  https://bugs.gentoo.org/show_bug.cgi?id=416685

This negates any benefit PF_MEMALLOC provides, so we introduce
an autotools check to disable the use of PF_MEMALLOC on
systems with patched kernels.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #126
2012-07-11 11:44:27 -07:00
Richard Yao ba9b5428fd Relicense zfs.gentoo.in from GPLv2 to 2-clause BSD
As the Gentoo sys-fs/zfs maintainer, I receive license compatibility
questions and at times, those questions can be harassing. I feel that
the presence of the GPL in Gentoo's package metadata promotes such
questions.  zfs.gentoo.in is the only GPLv2 licensed file in ZFS, so I
have taken the liberty of contacting all contributors to this file to
request permission to relicense it.

All of the contributors to this file have agreed to relicense it under
the 2-clause BSD license. I have added their Signed-offs to this commit,
in order of first contribution. Thank you everyone for being so
understanding.

Signed-off-by: devsk <devsku@gmail.com>
Signed-off-by: Alexey Shvetsov <alexxy@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrew Tselischev <andrewtselischev@gmail.com>
Signed-off-by: Zachary Bedell <zac@thebedells.org>
Signed-off-by: Gunnar Beutner <gunnar@beutner.name>
Signed-off-by: Kyle Fuller <inbox@kylefuller.co.uk>
Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Closes #819
2012-07-10 15:00:16 -07:00
Richard Yao a3873583c2 Use ULL suffix in constants
The lack of the ULL suffix causes warnings such as the following on
32-bit systems:

  In function 'zfsctl_is_snapdir':
  zfs-0.6.0//module/zfs/zfs_ctldir.c:151: warning: integer constant
  is too large for 'long' type

We add the ULL suffix to fix that.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #813
2012-07-10 11:31:55 -07:00
Richard Yao 973e8269bd Constify memory management functions
This prevents warnings in ZFS that were caused by changes necessary to
support PaX patched kernels. When debugging is enabled, these warnings
become build failures.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #131
2012-07-03 16:07:27 -07:00
Brian Behlendorf 42d3b990cf Update incorrect ddt_zap_lookup() assertion
When the ddt_zap_lookup() function was updated to dynamically
allocate memory for the cbuf variable, to save stack space, the
'csize <= sizeof (cbuf)' assertion was not updated.  The result
of this was that the size of the pointer was being used in the
comparison rather than the buffer size.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
2012-07-03 15:14:34 -07:00
Brian Behlendorf 33f507c0f3 Remove Chaos 4.x RPM support
The Chaos 4.x distribution is based on RHEL 5.x which is no longer
supported by ZoL since it uses a 2.6.18 kernel.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-07-02 15:17:08 -07:00
Brian Behlendorf fa881d4add Remove Chaos 4.x RPM support
The Chaos 4.x distribution is based on RHEL 5.x which is no longer
supported by ZoL since it uses a 2.6.18 kernel.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-07-02 15:16:05 -07:00
Prakash Surya 1a3a73d5d3 Support debug and debug-devel sub packages
This commit adds support for building debug and debug-devel sub packages
of the zfs-modules main package. This is to allow building packages
which are built against a debug kernel. By default, only packages are
built against a regular non-debug kernel. This can be toggled by passing
the '--with kernel-debug' parameter to rpmbuild.

Examples:

    # To build packages against only the non-debug kernel
    $ rpmbuild --rebuild --with kernel --without kernel-debug $SRPM

    # To build packages against only the debug kernel
    $ rpmbuild --rebuild --without kernel --with kernel-debug $SRPM

    # To build packages against debug and non-debug kernel
    $ rpmbuild --rebuild --with kernel --with kernel-debug $SRPM

Note: Only the RHEL 5/6, CHAOS 5, and Fedora distributions are supported
      for building the debug and debug-devel packages.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-07-02 11:32:19 -07:00
Prakash Surya 92c2f755ee Support debug and debug-devel sub packages
This commit adds support for building debug and debug-devel sub packages
of the spl-modules main package. This is to allow building packages
which are built against a debug kernel. By default, only packages are
built against a regular non-debug kernel. This can be toggled by passing
the '--with kernel-debug' parameter to rpmbuild.

Examples:

    # To build packages against only the non-debug kernel
    $ rpmbuild --rebuild --with kernel --without kernel-debug $SRPM

    # To build packages against only the debug kernel
    $ rpmbuild --rebuild --without kernel --with kernel-debug $SRPM

    # To build packages against debug and non-debug kernel
    $ rpmbuild --rebuild --with kernel --with kernel-debug $SRPM

Note: Only the RHEL 5/6, CHAOS 5, and Fedora distributions are supported
      for building the debug and debug-devel packages.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #115
2012-07-02 11:18:26 -07:00
Brian Behlendorf 44e406d712 PowerPC Compatibility
Usage of get_current() is not supported across all architectures.
The correct interface to use is the '#define current' which will
map to the appropriate function, usually current_thread_info().

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #119
2012-07-02 09:33:09 -07:00
Etienne Dechamps b6ad9671ac Add ZIL statistics.
The performance of the ZIL is usually the main bottleneck when dealing with
synchronous, write-heavy workloads (e.g. databases). Understanding the
behavior of the ZIL is required to diagnose performance issues for these
workloads, and to tune ZIL parameters (like zil_slog_limit) accordingly.

This commit adds a new kstat page dedicated to the ZIL with some counters
which, hopefully, scheds some light into what the ZIL is doing, and how it is
doing it.

Currently, these statistics are available in /proc/spl/kstat/zfs/zil.
A description of the fields can be found in zil.h.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #786
2012-06-29 09:56:51 -07:00
Brian Behlendorf 7164d09221 ZFS 0.6.0-rc9 2012-06-14 11:46:40 -07:00
Brian Behlendorf 50fe7a010c SPL 0.6.0-rc9 2012-06-14 11:45:59 -07:00
Pawel Jakub Dawidek 0cee24064a Speed up 'zfs list -t snapshot -o name -s name'
FreeBSD #xxx:  Dramatically optimize listing snapshots when user
requests only snapshot names and wants to sort them by name, ie.
when executes:

  # zfs list -t snapshot -o name -s name

Because only name is needed we don't have to read all snapshot
properties.

Below you can find how long does it take to list 34509 snapshots
from a single disk pool before and after this change with cold and
warm cache:

    before:

        # time zfs list -t snapshot -o name -s name > /dev/null
        cold cache: 525s
        warm cache: 218s

    after:

        # time zfs list -t snapshot -o name -s name > /dev/null
        cold cache: 1.7s
        warm cache: 1.1s

NOTE: This patch only appears in FreeBSD.  If/when Illumos picks up
the change we may want to drop this patch and adopt their version.
However, for now this addresses a real issue.

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #450
2012-06-14 09:49:04 -07:00
Darik Horn 74497b7ab6 Add zvol_inhibit_dev module option.
ZoL can create more zvols at runtime than can be configured during
system start, which hangs the init stack at reboot.

When a slow system has more than a few hundred zvols, udev will
fork bomb during system start and spend too much time in device
detection routines, so upstart kills it.

The zfs_inhibit_dev option allows an affected system to be rescued
by skipping /dev/zd* creation and thereby avoiding the udev
overload. All zvols are made inaccessible if this option is set, but
the `zfs destroy` and `zfs send` commands still work, and ZFS
filesystems can be mounted.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-06-13 17:05:16 -07:00
Richard Yao bc98d6c809 Make zvol_remove_link() print a more useful error message
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-06-13 16:27:19 -07:00
Richard Yao e0093fea58 Linux 3.4 compat, __clear_close_on_exec replaces FD_CLR
torvalds/linux@1dce27c5aa introduced
__clear_close_on_exec() as a replacement for FD_CLR. Further commits
appear to have removed FD_CLR from the Linux source tree.  This
causes the following failure:

  error: implicit declaration of function '__FD_CLR'
  [-Werror=implicit-function-declaration]

To correct this we update the code to use the current
__clear_close_on_exec() interface for readability.  Then we introduce
an autotools check to determine if __clear_close_on_exec() is available.
If it isn't then we define some compatibility logic which used the older
FD_CLR() interface.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #124
2012-06-13 16:18:51 -07:00
Brian Behlendorf eaac9ba510 Fix uninit variable in slab reclaim test
Gcc version 4.7.0 reports the delta.tv_sec in the slab reclaim test
as potentially unitialized.  In practice this will never occur but
to keep gcc happy we initialize the variable to zero.

Signed-off-by: Brian Behlendorf <behlendo@fedora-17-amd64.(none)>
2012-06-13 16:17:22 -07:00
Brian Behlendorf d53574e568 Mark zdev.conf as a config file
Prevent 'rpm -Uvh *.rpm" from automatically replacing your vdev.conf
file by flagging it as a non replacable config file.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #486
2012-06-13 13:02:43 -07:00
Brian Behlendorf fe2fc8f6d3 Workaround for failing zvol_id
This is not a proper fix.  It is just a workaround for the stack
smashing detected by gcc in zvol_id.  We simply disable the gcc
stack protector for now when building the zvol_id udev helper.
Once the root cause is resolved this patch should be reverted.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issues #569
2012-06-13 11:25:17 -07:00
Etienne Dechamps ee191e802c Make zil_slog_limit a tunable module parameter.
zil_slog_limit specifies the maximum commit size to be written to the separate
log device. Larger commits bypass the separate log device and go directly to
the data devices.

The optimal value for zil_slog_limit directly depends on the latency and
throughput characteristics of both the separate log device and the data disks.
Small synchronous writes are faster on low-latency separate log devices (e.g.
SSDs) whereas large synchronous writes are faster on high-latency data disks
(e.g. spindles) because of higher throughput, especially with a large array.
The point is, the line between "small" and "large" synchronous writes in this
scenario is heavily dependent on the hardware used. That's why it should be
made configurable.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #783
2012-06-12 08:45:53 -07:00
Daniel Verite c6327b63e6 Retry removal of busy minors
When failing to remove a zvol device link because it's busy, wait
a bit and retry in a loop instead of giving up immediately.  This
technique is similar to the loop in zpool_label_disk_wait(), with
the same goal: waiting for the asynchronous udev processes to finish
their work.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #692
2012-06-11 10:50:20 -07:00
Daniel Verite 92e91da208 Include <locale.h> to avoid error: 'LC_ALL' undeclared.
When compiling ZFS with CFLAGS=-O0 it will trigger the following error.
Resolve the issue by properly including locale.h.

  ../../cmd/mount_zfs/mount_zfs.c: In function 'main':
  ../../cmd/mount_zfs/mount_zfs.c:318:2: warning: implicit declaration
      of function 'setlocale' [-Wimplicit-function-declaration]
  ../../cmd/mount_zfs/mount_zfs.c:318:19: error: 'LC_ALL' undeclared
      (first use in this function)

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #724
2012-06-11 10:21:40 -07:00
Richard Yao 6a0936babc Linux 3.4 compat, d_make_root() replaces d_alloc_root()
torvalds/linux@adc0e91ab1 introduced
introduced d_make_root() as a replacement for d_alloc_root(). Further
commits appear to have removed d_alloc_root() from the Linux source
tree. This causes the following failure:

  error: implicit declaration of function 'd_alloc_root'
  [-Werror=implicit-function-declaration]

To correct this we update the code to use the current d_make_root()
interface for readability.  Then we introduce an autotools check
to determine if d_make_root() is available.  If it isn't then we
define some compatibility logic which used the older d_alloc_root()
interface.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #776
2012-06-11 10:04:49 -07:00
Etienne Dechamps ab85f8455b Honor logbias when writing to ZVOLs.
The logbias option is not taken into account when writing to ZVOLs. We fix
that by using the same logic as in the zfs filesystem write code
(see zfs_log.c).

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #774
2012-06-11 09:43:48 -07:00
Ned Bass cac1f230e0 Improve CONFIG_DEBUG_LOCK_ALLOC error message
The configure script error message for kernels built with
CONFIG_DEBUG_LOCK_ALLOC may give the impression that the issue is
strictly with license compliance.  To avoid confusion add some words
indicating that the linking stage will fail if the build continues.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #773
2012-06-11 09:28:04 -07:00
Brian Behlendorf 2371321e8a Fix invalid context bug
In the module unload path the vm_file_cache was being destroyed
under a spin lock.  Because this operation might sleep it was
possible, although very very unlikely, that this could result
in a deadlock.

This issue was indentified by using a Linux debug kernel and
has been fixed by moving the kmem_cache_destroy() out from under
the spin lock.  There is no need to lock this operation here.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes zfsonlinux/zfs#771
2012-06-11 09:17:45 -07:00
Brian Behlendorf abe5b8fb66 Improve 'zpool import' EBUSY error message
When a device is already open O_EXCL by another process the
`zpool import` will correctly fail.  However, the default failure
message isn't very helpful.  It may in fact be harmful if you
take its advise and destroy your pool.

    cannot import 'tank': pool is busy
            Destroy and re-create the pool from
            a backup source.

Improve the error message in the EBUSY case to simply print a
message indicating that the devices are current in use.  The user
will need to manually identify which process has the device open
exclusively and why.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-06-01 08:55:24 -07:00
Brian Behlendorf b04c9fc009 Add /dev/mapper/ to search path
When creating pools short device names may be used when those
devices appear in certain well known locations under /dev/.
This change adds /dev/mapper/ to that list.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-06-01 08:55:24 -07:00
Ned A. Bass 821b683436 Add vdev_id for JBOD-friendly udev aliases
vdev_id parses the file /etc/zfs/vdev_id.conf to map a physical path
in a storage topology to a channel name.  The channel name is combined
with a disk enclosure slot number to create an alias that reflects the
physical location of the drive.  This is particularly helpful when it
comes to tasks like replacing failed drives.  Slot numbers may also be
re-mapped in case the default numbering is unsatisfactory.  The drive
aliases will be created as symbolic links in /dev/disk/by-vdev.

The only currently supported topologies are sas_direct and sas_switch:

o  sas_direct - a channel is uniquely identified by a PCI slot and a
   HBA port

o  sas_switch - a channel is uniquely identified by a SAS switch port

A multipath mode is supported in which dm-mpath devices are handled by
examining the first running component disk, as reported by 'multipath
-l'.  In multipath mode the configuration file should contain a
channel definition with the same name for each path to a given
enclosure.

vdev_id can replace the existing zpool_id script on systems where the
storage topology conforms to sas_direct or sas_switch.  The script
could be extended to support other topologies as well.  The advantage
of vdev_id is that it is driven by a single static input file that can
be shared across multiple nodes having a common storage toplogy.
zpool_id, on the other hand, requires a unique /etc/zfs/zdev.conf per
node and a separate slot-mapping file.  However, zpool_id provides the
flexibility of using any device names that show up in
/dev/disk/by-path, so it may still be needed on some systems.

vdev_id's functionality subsumes that of the sas_switch_id script, and
it is unlikely that anyone is using it, so sas_switch_id is removed.

Finally, /dev/disk/by-vdev is added to the list of directories that
'zpool import' will scan.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #713
2012-06-01 08:55:14 -07:00
Brian Behlendorf e5b8562277 Extend CONFIG_DEBUG_LOCK_ALLOC check
The CONFIG_DEBUG_LOCK_ALLOC check at configure time was added to
detect when mutex_lock() is defined as a GPL-only symbol.  However,
the check as written only inferred this from this configuration
setting, it never actually checked.  This change introduces that
missing check to prevent false positives.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-06-01 08:51:56 -07:00
Jorgen Lundman 93b0dc92ea Fix ARM 64-bit division
Correctly implementating 64-bit division for ARM requires more than
just providing the __aeabi_uldivmod() and __aeabi_ldivmod() symbols.
They are need to be implemented is such a way that the quotient and
remainder and left in specific registers after the division operation
completes.  This change updates the wrapper functions to accomplish
this according to the official ARM Run-time ABI.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes zfsonlinux/zfs#706
2012-05-22 09:27:11 -07:00
Brian Behlendorf 38d31a1e57 Remove Solaris module emulation
Originally I believed that these interfaces would be needed.
However, in practice it turned out that it was more straight
forward and maintainable to use the native Linux interfaces.
As such, this is all dead code and can be safely removed.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #109
2012-05-18 13:57:44 -07:00
Richard Yao f90096c905 Modify KM_PUSHPAGE to use GFP_NOIO instead of GFP_NOFS
The resolution of issue #31 made KM_PUSHPAGE imply GFP_NOFS.  This
was done to prevent situations where filesystem operations which are
holding locks enter direct reclaim and attempt to reaquire those
same locks.  This clearly will result in a deadlock.

This works for datasets which are implemented in terms for filesystem
operations.  But unfortunately, swapping to a zvol will encounter
many of the same deadlocks and GFP_NOFS will not prevent this.  As
such, it is appropriate to extend KM_PUSHPAGE to use the broader
GFP_NOIO mask to handle these non-filesystem cases.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#342
Closes #105
2012-05-07 12:05:27 -07:00
Prakash Surya a9a7a01cf5 Add SPLAT test to exercise slab direct reclaim
This test is designed to verify that direct reclaim is functioning as
expected.  We allocate a large number of objects thus creating a large
number of slabs.  We then apply memory pressure and expect that the
direct reclaim path can easily recover those slabs.  The registered
reclaim function will free the objects and the slab shrinker will call
it repeatedly until at least a single slab can be freed.

Note it may not be possible to reclaim every last slab via direct reclaim
without a failure because the shrinker_rwsem may be contended.  For this
reason, quickly reclaiming 3/4 of the slabs is considered a success.

This should all be possible within 10 seconds.  For reference, on a
system with 2G of memory this test takes roughly 0.2 seconds to run.
It may take longer on larger memory systems but should still easily
complete in the alloted 10 seconds.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #107
2012-05-07 11:55:59 -07:00
Brian Behlendorf b78d4b9d98 Ensure a minimum of one slab is reclaimed
To minimize the chance of triggering an OOM during direct reclaim.
The kmem caches have been improved to make a best effort to reclaim
at least one slab when a reclaim function is registered.  This helps
avoid the case where objects are released but they are spread over
multiple slabs so no memory gets reclaimed.

Care has been taken to avoid deadlocking if the reclaim function
is unable to make forward progress.  Additionally, the reclaim
function may be skipped entirely if there are already free slabs
which can be safely reaped.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #107
2012-05-07 11:54:28 -07:00
Brian Behlendorf 06089b9e19 Ensure direct reclaim forward progress
The Linux direct reclaim path uses this out of band value to
determine if forward progress is being made.  Normally this is
incremented by kmem_freepages() which is part of the various
Linux slab implementations.  However, since we are using none
of that infrastructure we're responsible for incrementing this
count.

If no forward progress is detected and a subsequent allocation
fails the OOM killer will be invoked.  If there was forward
progress additional reclaim will be attempted via the page
cache and registerd shrinker until the allocation succeeds.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #107
2012-05-07 11:54:19 -07:00
Prakash Surya c0e0fc14e3 Ignore slab cache age and delay in direct reclaim
When memory pressure triggers direct memory reclaim, a slabs age
and delay should not prevent it from being freed. This patch ensures
these values are ignored, allowing an empty slab to be freed in this
code path no matter the value of its age and delay.

This prevents needless scanning of the partial slabs and has been
observed to significantly reduce the total cpu usage.  In addition,
it should allow for snappier reclaim under memory pressure.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #102
2012-05-07 11:50:04 -07:00
Prakash Surya cef7605c34 Throttle number of freed slabs based on nr_to_scan
Previously, the SPL tried to maintain Solaris semantics by freeing
all available (empty) slabs from its slab caches when the shrinker
was called. This is not desirable when running on Linux. To make
the SPL shrinker more Linux friendly, the actual number of freed
slabs from each of the slab caches is now derived from nr_to_scan
and skc_slab_objs.

Additionally, an accounting bug was fixed in spl_slab_reclaim()
which could cause us to reclaim one more slab than requested.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #101
2012-05-07 11:46:15 -07:00
Jorgen Lundman c421831192 Define the needed ISA types for ARM
Add the minimum required ISA types to support the ARM architecture.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-05-03 11:18:54 -07:00
Jorgen Lundman ef6f91ce0c Add missing 64-bit divide for 32-bit ARM
Leverage the existing generic 64-bit division operations which
were originally implemented for x86 to support ARM.  All that is
required is to make the symbols available to the linker with the
expected names.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-05-03 10:07:54 -07:00