Commit Graph

357 Commits

Author SHA1 Message Date
Brian Behlendorf
8d9a23e82c Retire legacy debugging infrastructure
When the SPL was originally written Linux tracepoints were still
in their infancy.  Therefore, an entire debugging subsystem was
added to facilite tracing which served us well for many years.

Now that Linux tracepoints have matured they provide all the
functionality of the previous tracing subsystem.  Rather than
maintain parallel functionality it makes sense to fully adopt
tracepoints.  Therefore, this patch retires the legacy debugging
infrastructure.

See zfsonlinux/zfs@bc9f413 for the tracepoint changes.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #408
2014-11-19 10:35:07 -08:00
Brian Behlendorf
917fef2732 Lower minimum objects/slab threshold
As long as we can fit a minimum of one object/slab there's no reason
to prevent the creation of the cache.  This effectively pushes the
maximum object size up to 32MB.  The splat cache tests were extended
accordingly to verify this functionality.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-11-05 10:08:21 -08:00
Alexander Pyhalov
3f4a13c497 Fix modules installation directory
When building zfs modules with kernel, compiled from deb.src, the
packaging process ends up installing the modules in the wrong place.

Signed-off-by: Alexander Pyhalov <apyhalov@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes zfsonlinux/zfs#2822
2014-10-28 09:49:24 -07:00
Richard Yao
ad9863e80b kmem_cache: Call constructor/destructor on each alloc/free
This has a few benefits. First, it fixes a regression that "Rework
generic memory allocation interfaces" appears to have triggered in
splat's slab_reap and slab_age tests. Second, it makes porting code from
Illumos to ZFSOnLinux easier. Third, it has the side effect of making
reclaim from slab caches that specify reclaim functions an order of
magnitude faster. The splat slab_reap test usually took 30 to 40
seconds. With this change, it takes 3 to 4.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #369
2014-10-28 09:21:08 -07:00
Tim Chase
802a4a2ad5 Linux 3.12 compat: shrinker semantics
The new shrinker API as of Linux 3.12 modifies "struct shrinker" by
replacing the @shrink callback with the pair of @count_objects and
@scan_objects.  It also requires the return value of @count_objects to
return the number of objects actually freed whereas the previous @shrink
callback returned the number of remaining freeable objects.

This patch adds support for the new @scan_objects return value semantics
and updates the splat shrinker test case appropriately.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #403
2014-10-28 09:20:13 -07:00
Brian Behlendorf
599662c538 Remove kern_path() wrapper
The kern_path() function has been available since Linux 2.6.28.
There is no longer a need to maintain this compatibility code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:52 -07:00
Brian Behlendorf
3d5392cefa Remove kvasprintf() wrapper
The kvasprintf() function has been available since Linux 2.6.22.
There is no longer a need to maintain this compatibility code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:52 -07:00
Brian Behlendorf
0fac9c9e6d Remove proc_handler() wrapper
As of Linux 2.6.32 the proc handlers where updated to expect only
five arguments.  Therefore there is no longer a need to maintain
this compatibility code and this infrastructure can be simplified.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:52 -07:00
Brian Behlendorf
68a829b29d Remove credential configure checks.
The groups_search() function was never exported by a mainline kernel
therefore we drop this compatibility code and always provide our own
implementation.

Additionally, the cred_t structure has been available since 2.6.29
so there is no longer a need to maintain compatibility code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
137af025f6 Remove set_fs_pwd() configure check
This function has never been exported by any mainline and was only
briefly available under RHEL5.  Therefore this check is being removed
and the code update to always use the wrapper function.

The next step will be to eliminate all this code.  If ZFS were updated
not to assume that it's pwd was / there would be no need for this.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
3c49a16989 Remove user_path_dir() wrapper
The user_path_dir() function has been available since Linux 2.6.27.
There is no longer a need to maintain this compatibility code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
44778f4110 Remove kallsyms_lookup_name() wrapper
After the removable of get_vmalloc_info(), the unused global memory
variables, and the optional dcache/icache shrinkers there is no
longer a need for the kallsyms compatibility code.  This allows
us to eliminate another brittle area of the code by removing the
kernel upcall this functionality depended on for older kernels.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
89a461e70c Remove shrink_{i,d}node_cache() wrappers
This is optional functionality which may or may not be useful to
ZFS when using older kernels.  It is never a hard requirement.
Therefore this functionality is being removed from the SPL and
a simpler slimmed down version will be added to ZFS.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
8bbbe46f86 Remove global memory variables
Platforms such as Illumos and FreeBSD have historically provided
global variables which summerize the memory state of a system.
Linux on the otherhand doesn't expose any of this information
to kernel modules and uses entirely different mechanisms for
memory management.

In order to simplify the original ZFS port to Linux these global
variables were emulated by the SPL for the benefit of ZFS.  As ZoL
has matured over the years it has moved steadily away from these
interfaces and now no longer depends on them at all.

Therefore, this patch completely removes the global variables
availrmem, minfree, desfree, lotsfree, needfree, swapfs_minfree,
and swapfs_reserve.  This greatly simplifies the memory management
code and eliminates a common area of confusion.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
e1310afae3 Remove get_vmalloc_info() wrapper
The get_vmalloc_info() function was used to back the vmem_size()
function.  This was always problematic and resulted in brittle
code because the kernel never provided a clean interface for
modules.

However, it turns out that the only caller of this function in
ZFS uses it to determine the total virtual address space size.
This can be determined easily without get_vmalloc_info() so
vmem_size() has been updated to take this approach which allows
us to shed the get_vmalloc_info() dependency.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
50e41ab1e1 Remove on_each_cpu() wrapper
The on_each_cpu() function has been available since Linux 2.6.27.
There is no longer a need to maintain this compatibility code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
2bc5666f53 Remove i_mutex() configure check
The inode structure has used i_mutex as its internal locking
primitive since 2.6.16.  The compatibility code to check for
the previous semaphore primitive has been removed.  However,
the wrapper function itself is being kept because it's entirely
possible this primitive will change again to allow finer grained
locking.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:51 -07:00
Brian Behlendorf
82f2f1a3af Simplify the time compatibility wrappers
Many of the time functions had grown overly complex in order to
handle kernel compatibility issues.  However, as of Linux 2.6.26
all the required functionality is available.  This allows us to
retire numerous configure checks and greatly simplify the time
compatibility wrappers.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:50 -07:00
Brian Behlendorf
87f8055a91 Map highbit64() to fls64()
The fls64() function has been available since Linux 2.6.16 and
it should be used to implemented highbit64().  This allows us
to provide an optimized implementation and simplify the code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:50 -07:00
Brian Behlendorf
9c91800d19 Remove CTL_UNNUMBERED sysctl interface
Support for the CTL_UNNUMBERED sysctl interface was removed in
Linux 2.6.19.  There is no longer any reason to maintain this
compatibility code.  There also issue any reason to keep around
the CTL_NAME macro and helpers so they have been retired.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:50 -07:00
Brian Behlendorf
b38bf6a4e3 Remove register_sysctl() compatibility code
The register_sysctl() interface has been stable since Linux 2.6.21.
There is no longer a need to maintain compatibility code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:50 -07:00
Brian Behlendorf
bb4dee3df2 Remove utsname() wrapper
There is no longer a need to wrap this because utsname() is provided
by the kernel and can be called directly.  This will require a small
change in the ZFS code because utsname is expected to be a global
structure and not a function.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:11:41 -07:00
Brian Behlendorf
aa363c5c05 Remove sysctl_vfs_cache_pressure assumption
The generic SPL cache shrinkers make the assumption that the
caches only contain VFS cache data and therefore should be scaled
based on vfs_cache_pressure.  This is not strictly true and it
should not be assumed.

Removing this tuning should not have any impact on the stock
behavior because vfs_cache_pressure=100 by default.  This means
that no scaling will take place.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:07:28 -07:00
Brian Behlendorf
a80d69caf0 Remove adaptive mutex implementation
Since the Linux 2.6.29 kernel all mutexes have been adaptive mutexs.
There is no longer any point in keeping this code so it is being
removed to simplify the code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:07:28 -07:00
Brian Behlendorf
3a92530563 Update code to use misc_register()/misc_deregister()
When the SPL was originally written it was designed to use the
device_create() and device_destroy() functions.  Unfortunately,
these functions changed considerably over the years making them
difficult to rely on.

As it turns out a better choice would have been to use the
misc_register()/misc_deregister() functions.  This interface
for registering character devices has remained stable, is simple,
and provides everything we need.

Therefore the code has been reworked to use this interface.  The
higher level ZFS code has always depended on these same interfaces
so this is also as a step towards minimizing our kernel dependencies.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:07:28 -07:00
Brian Behlendorf
0cb3dafccd Update SPLAT to use kmutex_t for portability
For consistency throughout the code update the SPLAT infrastructure
to use the wrapped mutex interfaces.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:07:28 -07:00
Brian Behlendorf
6203295438 Make license compatibility checks consistent
Apply the license specified in the META file to ensure the
compatibility checks are all performed consistently.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-17 15:07:28 -07:00
Brian Behlendorf
81857a34d1 Fix bug in SPLAT taskq:front
While running SPLAT on a kernel with CONFIG_DEBUG_ATOMIC_SLEEP
enabled the taskq:front was flagged as a test which might sleep
which in an unsafe context.  Specifically, the splat_vprint()
function which internally takes a mutex was being called under
a spin lock.  Moving the log function outside the spin lock
cleanly solves this issue.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-10-03 10:42:20 -07:00
Turbo Fredriksson
e3020723dc Linux 3.16 compat: smp_mb__after_clear_bit()
The smp_mb__{before,after}_clear_bit functions have been renamed
smp_mb__{before,after}_atomic.  Rather than adding a compatibility
function to handle this the code has been updated to use smp_wmb().

This has the advantage of being a stable functionally equivalent
interface.  On many architectures smp_mb__after_clear_bit() expands
to smp_wmb().  Others might be able to do something slightly more
efficient but this will be safe and correct on all of them.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #386
2014-09-22 16:24:55 -07:00
Richard Yao
ec18fe3ce8 Cleanup vn_rename() and vn_remove()
zfsonlinux/spl#bcb15891ab394e11615eee08bba1fd85ac32e158 implemented
Linux 3.6+ support by adding duplicate vn_rename and vn_remove
functions. The new ones were cleaner, but the duplicate functions made
the codebase less maintainable. This adds some compatibility shims that
allow us to retire the older vn_rename and vn_remove in favor of the new
ones on old kernels. The result is a net 143 line reduction in lines of
code and a cleaner codebase.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #370
2014-08-13 16:25:44 -07:00
Ned Bass
2fc44f66ec Linux 3.17 compat: remove wait_on_bit action function
Linux kernel 3.17 removes the action function argument from
wait_on_bit().  Add autoconf test and compatibility macro to support
the new interface.

The former "wait_on_bit" interface required an 'action' function to
be provided which does the actual waiting. There were over 20 such
functions in the kernel, many of them identical, though most cases
can be satisfied by one of just two functions: one which uses
io_schedule() and one which just uses schedule().  This API change
was made to consolidate all of those redundant wait functions.

References: torvalds/linux@7431620

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #378
2014-08-11 14:17:00 -07:00
Brian Behlendorf
f2297b5a89 Set spl_kmem_cache_slab_limit=16384 to default
For small objects the Linux slab allocator should be used to make the most
efficient use of the memory.  However, large objects are not supported by
the Linux slab and therefore the SPL implementation is preferred.  A cutoff
of 16K was determined to be optimal for architectures using 4K pages.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: DHE <git@dehacked.net>
Issue #356
Closes #379
2014-08-08 08:51:45 -07:00
Brian Behlendorf
c1aef26944 Set spl_kmem_cache_reclaim=0 to default
Reinstate the correct default behavior of returning the number of objects
in the cache for reclaim.  This behavior was disabled in recent releases
to do occasional reports of spinning in shrink_slabs().  Those issues have
been resolved and can no longer can be reproduced.  See commit 376dc35.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: DHE <git@dehacked.net>
Issue #358
Closes #379
2014-08-08 08:50:03 -07:00
Tim Chase
7f23e00109 Add functions and macros as used upstream.
Added highbit64() and howmany() which are used in recent upstream
code.  Both highbit() and highbit64() should at some point be
re-factored to use the optimized fls() and fls64() functions.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #363
2014-07-22 09:47:48 -07:00
Brian Behlendorf
377e12f14a Rate limit debugging stack traces
There have been issues in the past where excessive debug logging
to the console has resulted in significant performance impacts.
In the vast majority of these cases only a few stack traces are
required to diagnose the issue.  Therefore, stack traces dumped to
the console will now we limited to 5 every 60s.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Closes #374
2014-07-22 09:47:24 -07:00
Tim Chase
f6a869614e Safer debugging and assertion macros.
Spl's debugging and assertion macros macro used the typical do/while(0)
form for if/else friendliness, however, this limits their use in contexts
where a do loop is not valid; such as within another multi-statement
style macro.

The following macros have been converted to not use do/while(0):
	PANIC, ASSERT, ASSERTF, VERIFY, VERIFY3_IMPL

PANIC has been converted to a wrapper around the new spl_PANIC() function.

The other macros have been converted to use the "&&" operator for the
branch-predicition conditional and also to use spl_PANIC().

The __ASSERT() macro was not touched.  It is only used by the debugging
infrastructure and that code, including this macro, will be retired when
the tracepoint patches are merged.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #367
2014-07-01 15:14:43 -07:00
Brian Behlendorf
376dc35e22 Add spl_kmem_cache_reclaim module option
The correct behavior for all registered shrinkers is to return the
number of objects in their cache.  In theory this allows the Linux
VM to balance memory reclaim across all registered caches.

In commit b9b3715 this behavior was disabled in favor of returning
-1 which notifies the VM that no additional objects are available
for reclaim.  This was done as a workaround to resolve thrashing
in shrink_slabs() which could occur when memory was low and numerous
core where in reclaim.  Unfortunately, this has been observed to
increase the likelihood of OOM events when SPL slab consumers are
responsible for consuming the majority of memory.

Therefore, this patch makes this behavior tunable.  Setting the
spl_kmem_cache_reclaim module option to 0x1 will result in the
shrinker only being called once.  This is the default behavior.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Closes #358
2014-05-22 10:30:12 -07:00
Brian Behlendorf
a073aeb060 Add KMC_SLAB cache type
For small objects the Linux slab allocator has several advantages
over its counterpart in the SPL.  These include:

1) It is more memory-efficient and packs objects more tightly.
2) It is continually tuned to maximize performance.

Therefore it makes sense to layer the SPLs slab allocator on top
of the Linux slab allocator.  This allows us to leverage the
advantages above while preserving the Illumos semantics we depend
on.  However, there are some things we need to be careful of:

1) The Linux slab allocator was never designed to work well with
   large objects.  Because the SPL slab must still handle this use
   case a cut off limit was added to transition from Linux slab
   backed objects to kmem or vmem backed slabs.

   spl_kmem_cache_slab_limit - Objects less than or equal to this
   size in bytes will be backed by the Linux slab.  By default
   this value is zero which disables the Linux slab functionality.
   Reasonable values for this cut off limit are in the range of
   4096-16386 bytes.

   spl_kmem_cache_kmem_limit - Objects less than or equal to this
   size in bytes will be backed by a kmem slab.  Objects over this
   size will be vmem backed instead.  This value defaults to
   1/8 a page, or 512 bytes on an x86_64 architecture.

2) Be aware that using the Linux slab may inadvertently introduce
   new deadlocks.  Care has been taken previously to ensure that
   all allocations which occur in the write path use GFP_NOIO.
   However, there may be internal allocations performed in the
   Linux slab which do not honor these flags.  If this is the case
   a deadlock may occur.

The path forward is definitely to start relying on the Linux slab.
But for that to happen we need to start building confidence that
there aren't any unexpected surprises lurking for us.  And ideally
need to move completely away from using the SPLs slab for large
memory allocations.  This patch is a first step.

NOTES:
1) The KMC_NOMAGAZINE flag was leveraged to support the Linux slab
   backed caches but it is not supported for kmem/vmem backed caches.

2) Regardless of the spl_kmem_cache_*_limit settings a cache may
   be explicitly set to a given type by passed the KMC_KMEM,
   KMC_VMEM, or KMC_SLAB flags during cache creation.

3) The constructors, destructors, and reclaim callbacks are all
   functional and will be called regardless of the cache type.

4) KMC_SLAB caches will not appear in /proc/spl/kmem/slab due to
   the issues involved in presenting correct object accounting.
   Instead they will appear in /proc/slabinfo under the same names.

5) Several kmem SPLAT tests needed to be fixed because they relied
   incorrectly on internal kmem slab accounting.  With the updated
   test cases all the SPLAT tests pass as expected.

6) An autoconf test was added to ensure that the __GFP_COMP flag
   was correctly added to the default flags used when allocating
   a slab.  This is required to ensure all pages in higher order
   slabs are properly refcounted, see ae16ed9.

7) When using the SLUB allocator there is no need to attempt to
   set the __GFP_COMP flag.  This has been the default behavior
   for the SLUB since Linux 2.6.25.

8) When using the SLUB it may be desirable to set the slub_nomerge
   kernel parameter to prevent caches from being merged.

Original-patch-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: DHE <git@dehacked.net>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Closes #356
2014-05-22 10:28:01 -07:00
Chunwei Chen
ad3412efd7 Linux 3.15: vfs_rename() added a flags argument
Detect the updated vfs_rename() interface and call it with an
extra flags argument.

References:
  torvalds/linux@520c8b1

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #355
2014-05-07 13:38:17 -07:00
Andrey Vesnovaty
703371d8c7 Evenly distribute the taskq threads across available CPUs
The problem is described in commit aeeb4e0c0a.
However, instead of disabling the binding to CPU altogether we just keep the
last CPU index across calls to taskq_create() and thus achieve even
distribution of the taskq threads across all available CPUs.

The implementation based on assumption that task queues initialization
performed in serial manner.

Signed-off-by: Andrey Vesnovaty <andrey.vesnovaty@gmail.com>
Signed-off-by: Andrey Vesnovaty <andreyv@infinidat.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #336
2014-04-25 15:29:18 -07:00
Chunwei Chen
ae16ed992b Fix crash when using ZFS on Ceph rbd
When using __get_free_pages to get high order memory, only the first page's
_count will set to 1, other's will be 0. When an internal page get passed into
rbd, it will eventully go into tcp_sendpage. There, it will be called with
get_page and put_page, and get freed erroneously when _count jump back to 0.

The solution to this problem is to use compound page. All pages in a
high order compound page share a single _count. So get_page and put_page in
tcp_sendpage will not cause _count jump to 0.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #251
2014-04-25 15:26:52 -07:00
Richard Yao
89aa97059d Change spl_kmem_cache_expire default setting to 2
This behavior is more consistent with the way memory reclaim
is expected to work under Linux.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #349
2014-04-14 16:29:01 -07:00
Andrey Vesnovaty
bdfbe594a1 Expose max/min objs per slab and max slab size
By default maximal number of objects in slab can't exceed (16*2 - 1) and slab
size can't exceed 32M.
Today's high end servers having couple hundreds of RAM available for ARC may
run into a trouble with virtual memory because of the restriction mentioned
above.

Problem:
Reasons for very high number of virtual memory allocations:
	* Real slab size very small relative to the size of the entire RAM
	* Slabs allocated on virtual memory and fill entire ARC

The result is very high number of allocated virtual memory ranges (hundreds of
ranges). When virtual memory subsystem manages high number of ranges its
performance become so poor that it freezes from time to time.

Solution:
Number of objects per slab should be increased taking into account maximal
slab size which can also be increased if needed.

Signed-off-by: Andrey Vesnovaty <andrey.vesnovaty@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #337
2014-04-14 09:42:04 -07:00
Chunwei Chen
545e9ac00a Add ddi_time_after and friends
When comparing times gotten from ddi_get_lbolt, we have to take account of
wrap around of jiffies. Therefore, we cannot use 't1 < t2'. Instead we should
use 't1 - t2 < 0'.

This patch add ddi_time_after and friends to address this issue. They have
strict type restriction, clock_t for vanilla and int64_t for 64 version, to
prevent type conversion from screwing things.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #335
2014-04-14 09:32:01 -07:00
Richard Yao
acf0ade362 Simplify hostid logic
There is plenty of compatibility code for a hw_hostid
that isn't used by anything. At the same time, there are apparently
issues with the current hostid logic. coredumb in #zfsonlinux on
freenode reported that Fedora 17 changes its hostid on every boot, which
required force importing his pool. A suggestion by wca was to adopt
FreeBSD's behavior, where it treats hostid as zero if /etc/hostid does
not exist

Adopting FreeBSD's behavior permits us to eliminate plenty of code,
including a userland helper that invokes the system's hostid as a
fallback.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #224
2014-04-14 09:04:41 -07:00
Tim Chase
3ceb71e896 Call kthread_create() correctly with fixed arguments.
The kernel's kthread_create() function is defined as "..." and there is
no va_list variant at the moment.  The task name is pre-formatted into
a local buffer and passed to kthread_create() with fixed arguments.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #347
2014-04-11 09:41:40 -07:00
Tim Chase
ed650dee76 De-inline spl_kthread_create().
The function was defined as a static inline with variable arguments
which causes gcc to generate errors on some distros.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #346
2014-04-09 19:17:12 -07:00
Tim Chase
17a527cb0f Support post-3.13 kthread_create() semantics.
Provide spl_kthread_create() as a wrapper to the kernel's kthread_create()
to provide pre-3.13 semantics.  Re-try if the call is interrupted or if it
would have returned -ENOMEM.  Otherwise return NULL.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #339
2014-04-08 12:44:42 -07:00
Brian Behlendorf
e19101e08f splat cred:groupmember: Fix false positives
Due to certain assumptions made in the the cred:groupmember test it
could result in false positives when run on specific distributions.
This was solely a bug in the test case and not in the groupmember()
function which the test case was validating.

To prevent future false positives the test case has been rewritten
to be both more rigerous and to make fewer assumptions about the
system.

Minor style cleanup was done to cr_groups_search() and groupmember()
functions.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-04-08 12:44:41 -07:00
Brian Behlendorf
668d2a0da5 splat kmem:slab_reclaim: Test cleanup
By setting __GFP_NORETRY the kernel memory reclaim logic was allowed to
abort early and dump a falled allocation stack to the console.  Since
this was done in a tight loop to fill memory it could result in a large
number of stacks being dumped to the console.  This in turn slowed down
the test sufficiently so it exceeded the time limit and failed.

To resolve this issue the __GFP_NORETRY flag is being removed.  This is
how it should have been called originally to ensure we're simulating
the behavior of most callers which will use the GFP_KERNEL flag.

In addition, the reclaim granularity of 1000 objects was far to coarse
for this to be a realistic test.  For kmem:slab_reclaim there might
only be a few thousand objects total in the cache.  Therefore, the
SPLAT_KMEM_OBJ_RECLAIM constant for these tests was lowered.  This
will cause the reclaim callback to run more frequently which makes
for a better test case.

The frequency of the cache reaping in kmem:slab_reap was increased
to accommodate the reduced number of objects released during the
reclaim.

These changes only impact the test cases and were done to remove
false positives caused by the test case itself.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-04-08 12:44:41 -07:00