The `pgprot` argument has been removed from `__vmalloc` in Linux 5.8,
being `PAGE_KERNEL` always now [1].
Detect this during configure and define a wrapper for older kernels.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/mm/vmalloc.c?h=next-20200605&id=88dca4ca5a93d2c09e5bbc6a62fbfc3af83c4fca
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Co-authored-by: Michael Niewöhner <foss@mniewoehner.de>
Signed-off-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Closes#10422
When growing the size of a (VMEM or KVMEM) kmem cache, spl_cache_grow()
always does taskq_dispatch(spl_cache_grow_work), and then waits for the
KMC_BIT_GROWING to be cleared by the taskq thread.
The taskq thread (spl_cache_grow_work()) does:
1. allocate new slab and add to list
2. wake_up_all(skc_waitq)
3. clear_bit(KMC_BIT_GROWING)
Therefore, the waiting thread can wake up before GROWING has been
cleared. It will see that the growing has not yet completed, and go
back to sleep until it hits the 100ms timeout.
This can have an extreme performance impact on workloads that alloc/free
more than fits in the (statically-sized) magazines. These workloads
allocate and free slabs with high frequency.
The problem can be observed with `funclatency spl_cache_grow`, which on
some workloads shows that 99.5% of the time it takes <64us to allocate
slabs, but we spend ~70% of our time in outliers, waiting for the 100ms
timeout.
The fix is to do `clear_bit(KMC_BIT_GROWING)` before
`wake_up_all(skc_waitq)`.
A future investigation should evaluate if we still actually need to
taskq_dispatch() at all, and if so on which kernel versions.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Wilson <gwilson@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#9989
On kernels with KASAN enabled the following failure can be observed as
soon as the zfs module is loaded:
VERIFY(IS_P2ALIGNED(ptr, PAGE_SIZE)) failed
PANIC at spl-kmem-cache.c:228:kv_alloc()
The problem is kmalloc() has never guaranteed aligned allocations; this
requirement resulted in zfsonlinux/spl@8b45dda which removed all
kmalloc() usage in kv_alloc().
Until a GFP_ALIGNED flag (or equivalent functionality) is provided by
the kernel this commit partially reverts 66955885 and 6d948c35 to
prevent k(v)malloc() allocations in kv_alloc().
Reviewed-by: Kjeld Schouten <kjeld@schouten-lebbing.nl>
Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes#9813
As of cppcheck 1.82 warnings are issued when using the list_for_each_*
functions with an uninitialized variable. Functionally, this is fine
but to resolve the warning initialize these variables.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#9732
This adds a new KMC_KVMEM flag was added to enforce use of the
kvmalloc allocator in kmem_cache_create even for large blocks, which
may also increase performance in some specific cases (e.g. zstd), too.
Default to KVMEM instead of VMEM in spl_kmem_cache_create.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Signed-off-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Closes#9034
This patch implements use of kvmalloc for GFP_KERNEL allocations, which
may increase performance if the allocator is able to allocate physical
memory, if kvmalloc is available as a public kernel interface (since
v4.12). Otherwise it will simply fall back to virtual memory (vmalloc).
Also fix vmem_alloc implementation which can lead to slow allocations
since the first attempt with kmalloc does not make use of the noretry
flag but tells the linux kernel to retry several times before it fails.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Signed-off-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Closes#9034
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Signed-off-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Closes#9034
Increase the minimum supported kernel version from 2.6.32 to 3.10.
This removes support for the following Linux enterprise distributions.
Distribution | Kernel | End of Life
---------------- | ------ | -------------
Ubuntu 12.04 LTS | 3.2 | Apr 28, 2017
SLES 11 | 3.0 | Mar 32, 2019
RHEL / CentOS 6 | 2.6.32 | Nov 30, 2020
The following changes were made as part of removing support.
* Updated `configure` to enforce a minimum kernel version as
specified in the META file (Linux-Minimum: 3.10).
configure: error:
*** Cannot build against kernel version 2.6.32.
*** The minimum supported kernel version is 3.10.
* Removed all `configure` kABI checks and matching C code for
interfaces which solely predate the Linux 3.10 kernel.
* Updated all `configure` kABI checks to fail when an interface is
missing which was in the 3.10 kernel up to the latest 5.1 kernel.
Removed the HAVE_* preprocessor defines for these checks and
updated the code to unconditionally use the verified interface.
* Inverted the detection logic in several kABI checks to match
the new interface as it appears in 3.10 and newer and not the
legacy interface.
* Consolidated the following checks in to individual files. Due
the large number of changes in the checks it made sense to handle
this now. It would be desirable to group other related checks in
the same fashion, but this as left as future work.
- config/kernel-blkdev.m4 - Block device kABI checks
- config/kernel-blk-queue.m4 - Block queue kABI checks
- config/kernel-bio.m4 - Bio interface kABI checks
* Removed the kABI checks for sops->nr_cached_objects() and
sops->free_cached_objects(). These interfaces are currently unused.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#9566
Currently, for certain sizes and classes of allocations we use
SPL caches that are backed by caches in the Linux Slab allocator
to reduce fragmentation and increase utilization of memory. The
way things are implemented for these caches as of now though is
that we don't keep any statistics of the allocations that we
make from these caches.
This patch enables the tracking of allocated objects in those
SPL caches by making the trade-off of grabbing the cache lock
at every object allocation and free to update the respective
counter.
Additionally, this patch makes those caches visible in the
/proc/spl/kmem/slab special file.
As a side note, enabling the specific counter for those caches
enables SDB to create a more user-friendly interface than
/proc/spl/kmem/slab that can also cross-reference data from
slabinfo. Here is for example the output of one of those
caches in SDB that outputs the name of the underlying Linux
cache, the memory of SPL objects allocated in that cache,
and the percentage of those objects compared to all the
objects in it:
```
> spl_kmem_caches | filter obj.skc_name == "zio_buf_512" | pp
name ... source total_memory util
----------- ... ----------------- ------------ ----
zio_buf_512 ... kmalloc-512[SLUB] 16.9MB 8
```
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes#9474
Make the metaslab platform agnostic again by adding
accessor functions which can be implemented by each
platform.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes#9404
Move platform specific Linux source under module/os/linux/
and update the build system accordingly. Additional code
restructuring will follow to make the common code fully
portable.
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Macy <mmacy@FreeBSD.org>
Closes#9206
Michael Niewöhner
Matthew Ahrens
loli10K
Ubuntu
Michael Niewöhner
Michael Niewöhner
Brian Behlendorf
Serapheim Dimitropoulos
Matthew Macy
Matthew Macy