To properly support CONFIG_PREEMPT enabled kernels, we must refrain from
using a CPU index when preemption is enabled. As a result, this change
moves the trace_set_debug_header call (which calls smp_processor_id)
within trace_get_tcd and trace_put_tcd (which disable and enable
preemption respectively).
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#160
Add the /usr/src/spl-<version>-<release>/<kernel> directory to
the spl-modules-devel package. This ensures that this directory
will be removed when the package is removed.
We do not include the higher level /usr/src/spl-<version>-<release>
directory since there may be builds for multiple kernels. Instead,
a %postun rmdir is added which attempts to remove this directory.
It will only succeed when the last spl-modules-devel-* package
for this specific release is removed.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
This commit adds support for building a spl-modules-dkms sub package
built around Dynamic Kernel Module Support. This is to allow building
packages using the DKMS infrastructure which is intended to ease the
burden of kernel version changes, upgrades, etc.
By default spl-modules-dkms-* sub package will be built as part of
the 'make rpm' target. Alternately, you can build only the DKMS
module package using the 'make rpm-dkms' target.
Examples:
# To build packaged binaries as well as a dkms packages
$ ./configure && make rpm
# To build only the packaged binary utilities and dkms packages
$ ./configure && make rpm-utils rpm-dkms
Note: Only the RHEL 5/6, CHAOS 5, and Fedora distributions are
supported for building the dkms sub package.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#535
In the comments of commit 723aa3b0c2,
mmatuska reported that the test for invalidate_inodes_check() is broken
if invalidate_inodes() takes two arguments.
This patch fixes the issue by resorting to another approach for
detecting invalidate_inodes_check(): is simply checks if
invalidate_inodes is defined as a macro. If it is, then it concludes
that invalidate_inodes_check() is available. This will continue to work
even if the prototype of invalidate_inodes_check() changes over time.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#148
A preprocessor definition renders this harmless. However, it is a good
idea to change this to be consistent.
Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Support in-tree builtin module building.
These commits add support for compiling the SPL module as a built-in
kernel module by copying the module code into the kernel source tree.
Here's the procedure:
- Create your kernel configuration (`.config` file) as usual. This
has to be done first so that SPL's configure script is able to
detect kernel features correctly.
- Run `make prepare scripts` inside the kernel source tree.
- Run `./configure --enable-linux-builtin --with-linux=/usr/src/linux-...`
inside the SPL directory.
- Run `./copy-builtin /usr/src/linux-...` inside the SPL directory.
- In the kernel source tree, enable the `CONFIG_SPL` option
(e.g. using `make menuconfig`).
- Build the kernel as usual.
SPL module parameters can be set at boot time using the following syntax
on the kernel command line: `spl.parameter_name=parameter_value`.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#851
Currently, the SPL tries to determine the hostid at module load. The
hostid is usually determined by running the userland program "hostid"
during module initialization.
Unfortunately, when the module initializes, it may be way too soon to be
able to run any userland programs. This is especially true when the
module is compiled directly inside the kernel (built-in); in that case,
the SPL would try to run hostid when the kernel is still initializing,
which of course is doomed to fail.
This patch fixes the issue by deferring hostid generation until
something actually needs the hostid (that is, when zone_get_hostid() is
called), thus switching to a "on-initialization" model to a "on-demand"
(lazy loading) model. ZFS only needs the hostid when some pool
operations are requested, and this always happens way after the kernel
has finished initialization, thus solving the problem.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#851
This commit introduces a "copy-builtin" script designed to prepare a
kernel source tree for building SPL as a builtin module. The script
makes a full copy of all needed files, thus making the kernel source
tree fully independent of the spl source package.
To achieve that, some compilation flags (-include, -I) have been moved
to module/Makefile. This Makefile is only used when compiling external
modules; when compiling builtin modules, a Kbuild file generated by the
configure-builtin script is used instead. This makes sure Makefiles
inside the kernel source tree does not contain references to the spl
source package.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#851
This patch adds a new autoconf function: SPL_LINUX_TRY_COMPILE_SYMBOL.
This new function does the following:
- Call LINUX_TRY_COMPILE with the specified parameters.
- If unsuccessful, return false.
- If successful and we're configuring with --enable-linux-builtin,
return true.
- Else, call CHECK_SYMBOL_EXPORT with the specified parameters and
return the result.
All calls to CHECK_SYMBOL_EXPORT are converted to
LINUX_TRY_COMPILE_SYMBOL so that the tests work even when configuring
for builtin on a kernel which doesn't have loadable module support, or
hasn't been built yet.
The only exception are:
- AC_GET_VMALLOC_INFO, because we don't even have a public header to
include in the test case, but that's okay considering this symbol can
be ignored just fine.
- SPL_AC_DEVICE_CREATE, which is legacy API for 2.6.18 kernels. Since
kernels this old are no longer supported it should arguably just be
removed entirely from the build system.
Note that we're also checking for the correct prototype with an actual
call, which was not the case with CHECK_SYMBOL_EXPORT. However, for
"complicated" test cases like with multiple symbol versions (e.g.
vfs_fsync), we stick with the original behavior and only check for the
function's existence.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#851
Currently, when building a test case, we're compiling an entire Linux
module from beginning to end. This includes the MODPOST stage, which
generates a "conftest.mod.c" file with some boilerplate module
declaration code.
This poses a problem when configuring for built-in on kernels which have
loadable module support disabled. In this case conftest.mod.c is
referencing disabled code, resulting in a compilation failure, thus
breaking the tests.
This patch fixes the issue by faking the modpost stage when the
--enable-linux-builtin option is provided. It does so by forcing the
modpost command to be /bin/true, and using an empty conftest.mod.c file.
The test module still compiles fine, although the result isn't loadable,
but we don't really care at this point.
Note it is important to preserve the modpost stage when building out of
tree. This allows for the posibility of configure checks to leverage
this phase to identify GPL-only symbols.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#851
This patch adds a new option to configure: --enable-linux-builtin. When
this option is used, the following happens:
- Compilation of kernel modules is disabled.
- A failure to find UTS_RELEASE is followed by a suggestion to run
"make prepare" on the kernel source tree.
This patch also adds a new test which tries to compile an empty module
as a basic toolchain sanity test. If it fails and the option was
specified, the error is followed by a suggestion to run "make scripts"
on the kernel source tree.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#851
Commit 3160d4f56b changed the set of
conditions under which spl_mutex_spin_max would be implemented as a
function by changing an #if in sys/mutex.h. The corresponding
implementation file spl-mutex.c, however, has not been updated to
reflect the change. This results in undefined reference errors on
spl_mutex_spin_max under the following condition:
((!CONFIG_SMP || CONFIG_DEBUG_MUTEXES) && HAVE_MUTEX_OWNER && HAVE_TASK_CURR)
This patch fixes the issue by using the same #if in sys/mutex.h and
spl-mutex.c.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#851
Currently, when configure --with-config is used, selective compilation
is only effective for the simple "make" case. Package builders (e.g.
make rpm) still build everything (utils and modules). This patch fixes
that.
This patch also drops the duplicate rpm-modules build target.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Issue zfsonlinux/zfs#851
In zfs, each module Makefile contains a MODULE variable which contains
the name of the module, and the following declarations reference this
variable.
In spl, there is a MODULES variable which is never used. Rename it to
MODULE and use it like in zfs. This improves consistency between the two
build systems.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfsonlinux/zfs#851
Explicitly cast the sizeof in hostid_read() to prevent the
following compiler warning on 32-bit systems.
module/spl/spl-generic.c:490:10: error: format '%lu' expects
argument of type 'long unsigned int', but argument 4 has type
'unsigned int' [-Werror=format]
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
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>
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
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
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
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>
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
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
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
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)>
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>
Closeszfsonlinux/zfs#771
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>
Closeszfsonlinux/zfs#706
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
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#342Closes#105
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
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
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
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
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
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>
As of the removal of the taskq work list made in commit:
commit 2c02b71b14
Author: Prakash Surya <surya1@llnl.gov>
Date: Mon Dec 5 17:32:48 2011 -0800
Replace tq_work_list and tq_threads in taskq_t
To lay the ground work for introducing the taskq_dispatch_prealloc()
interface, the tq_work_list and tq_threads fields had to be replaced
with new alternatives in the taskq_t structure.
the comment above taskq_wait_check has been incorrect. This change is an
attempt at bringing that description more in line with the current
implementation. Essentially, references to the old task work list had to
be updated to reference the new taskq thread active list.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #65
Long ago I added support to the spl for condition variable names
because I thought they might be needed. It turns out they aren't.
In fact the official Solaris cv_init(9F) man page discourages
their use in the kernel.
cv_init(9F)
Parameters
name - Descriptive string. This is obsolete and should be
NULL. (Non-NULL strings are legal, but they're a
waste of kernel memory.)
Therefore, I'm removing them from the spl to reclaim this memory
and adding an ASSERT() to ensure no new consumers are added which
make use of the name.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Include the ZFS_META_RELEASE in the module load/unload messages
to more clearly indicate exactly what version of the SPL has
been loaded.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Improve the distribution detection by moving the tests for
distribution specific files first. The Ubuntu and Debian
checks are left for last because they are the least likely
to be unique. This is particularly true in the case of Debian
since so many distributions are based on Debian.
Since this is currently only used to identify the correct
packaging method for this system the result in many instances
is simply cosmetic.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Allow a source rpm to be rebuilt with debugging enabled. This
avoids the need to have to manually modify the spec file. By
default debugging is still largely disabled. To enable specific
debugging features use the following options with rpmbuild.
'--with debug' - Enables ASSERTs
'--with debug-log' - Enables the internal debug log
'--with debug-kmem' - Enables basic memory accounting
'--with debug-kmem-tracking' - Enables detailed memory tracking
# For example:
$ rpmbuild --rebuild --with debug spl-modules-0.6.0-rc6.src.rpm
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
When building the spl with --disable-debug-log the __SDEBUG()
macro and spl_debug_* helper functions were undefined. This
change adds the missing functions so the upper layers compiling
against the spl don't need to be aware of how the spl was built.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Add the bare minimum functionality to support dynamic kstats. A
complete kstat implementation should be done as part of issue #84.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #84
Until now the notion of an internal debug logging infrastructure
was conflated with enabling ASSERT()s. This patch clarifies things
by cleanly breaking the two subsystem apart. The result of this
is the following behavior.
--enable-debug - Enable/disable code wrapped in ASSERT()s.
--disable-debug ASSERT()s are used to check invariants and
are never required for correct operation.
They are disabled by default because they
may impact performance.
--enable-debug-log - Enable/disable the debug log infrastructure.
--disable-debug-log This infrastructure allows the spl code and
its consumer to log messages to an in-kernel
log. The granularity of the logging can be
controlled by a debug mask. By default the
mask disables most debug messages resulting
in a negligible performance impact. Because
of this the debug log is enabled by default.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Testing has shown that tq->tq_lock can be highly contended when a
large number of small work items are dispatched. The lock hold time
is reduced by the following changes:
1) Use exclusive threads in the work_waitq
When a single work item is dispatched we only need to wake a single
thread to service it. The current implementation uses non-exclusive
threads so all threads are woken when the dispatcher calls wake_up().
If a large number of threads are in the queue this overhead can become
non-negligible.
2) Conditionally add/remove threads from work waitq
Taskq threads need only add themselves to the work wait queue if
there are no pending work items.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #32
This reverts commit ec2b41049f.
A race condition was introduced by which a wake_up() call can be lost
after the taskq thread determines there is no pending work items,
leading to deadlock:
1. taksq thread enables interrupts
2. dispatcher thread runs, queues work item, call wake_up()
3. taskq thread runs, adds self to waitq, sleeps
This could easily happen if an interrupt for an IO completion was
outstanding at the point where the taskq thread reenables interrupts,
just before the call to add_wait_queue_exclusive(). The handler would
run immediately within the race window.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #32
Prakash Surya
Brian Behlendorf
Etienne Dechamps
Richard Yao
Etienne Dechamps
Richard Yao
Brian Behlendorf
Jorgen Lundman
Ned Bass