Existing option noverify disables both random src/dst address offset
setup and data verification. Sometimes, we need to control random
src/dst address setup and verification separately, such as disabling
random to make sure that test covers addresses in all interleaving
banks, but data verification is still performed.
This patch adds option norandom to disable random offset setup. Option
noverify has been changed to disable data verification only.
Cc: Joey Zheng <yu.zheng@hxt-semitech.com>
Signed-off-by: Yang Shunyong <shunyong.yang@hxt-semitech.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The type of arg passed to dmatest_callback is struct dmatest_done.
It refers to test_done in struct dmatest_thread, not done_wait.
Fixes: 6f6a23a213 ("dmaengine: dmatest: move callback wait ...")
Signed-off-by: Yang Shunyong <shunyong.yang@hxt-semitech.com>
Acked-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Commit adfa543e73 ("dmatest: don't use set_freezable_with_signal()")
introduced a bug (that is in fact documented by the patch commit text)
that leaves behind a dangling pointer. Since the done_wait structure is
allocated on the stack, future invocations to the DMATEST can produce
undesirable results (e.g., corrupted spinlocks).
Commit a9df21e34b ("dmaengine: dmatest: warn user when dma test times
out") attempted to WARN the user that the stack was likely corrupted but
did not fix the actual issue.
This patch fixes the issue by pushing the wait queue and callback
structs into the the thread structure. If a failure occurs due to time,
dmaengine_terminate_all will force the callback to safely call
wake_up_all() without possibility of using a freed pointer.
Cc: stable@vger.kernel.org
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=197605
Fixes: adfa543e73 ("dmatest: don't use set_freezable_with_signal()")
Reviewed-by: Sinan Kaya <okaya@codeaurora.org>
Suggested-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Commit adfa543e73 ("dmatest: don't use set_freezable_with_signal()")
introduced a bug (that is in fact documented by the patch commit text)
that leaves behind a dangling pointer. Since the done_wait structure is
allocated on the stack, future invocations to the DMATEST can produce
undesirable results (e.g., corrupted spinlocks). Ideally, this would be
cleaned up in the thread handler, but at the very least, the kernel
is left in a very precarious scenario that can lead to some long debug
sessions when the crash comes later.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=197605
Signed-off-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There are no in kernel consumers for DMA_SG op. Removing operation,
dead code, and test code in dmatest.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Gary Hook <gary.hook@amd.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Kedareswara rao Appana <appana.durga.rao@xilinx.com>
Cc: Li Yang <leoyang.li@nxp.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Introducing memset test into dmatest. This change allows us to test
memset capable HW using the dmatest test procedure. The new dmatest
value for memset is 2 and it is not the default value.
Memset support patch shares the same code path as the other dmatest
code to reuse as much as we can.
The first value inside the source buffer is used as a pattern
to fill in the destination buffer space.
Prior to running the test, source/destination buffers are initialized
in the current code.
"The remaining bits are the inverse of a counter which increments by
one for each byte address."
Memset test will fill in the upper bits of pattern with the inverse of
fixed counter value 1 as opposed to an incrementing value in a loop.
An example run is as follows:
echo dma0chan0 > /sys/module/dmatest/parameters/channel
echo 2 > /sys/module/dmatest/parameters/dmatest
echo 2000 > /sys/module/dmatest/parameters/timeout
echo 10 > /sys/module/dmatest/parameters/iterations
echo 1 > /sys/module/dmatest/parameters/run
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When using dmatest with sg_buffers=128 I stumbled upon the problem, that
the "map_cnt" variable of "struct dmaengine_unmap_data" was set to 0.
"map_cnt" is an "u8" variable, resulting in an overrun when its
value is set to src_cnt + dst_cnt, to twice the sg_buffer value.
This patch adds a small check to dmatest, so that this confusing error
is detected and the test is aborted.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Kedareswara rao Appana <appanad@xilinx.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
But first update usage sites with the new header dependency.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
ktime_set(S,N) was required for the timespec storage type and is still
useful for situations where a Seconds and Nanoseconds part of a time value
needs to be converted. For anything where the Seconds argument is 0, this
is pointless and can be replaced with a simple assignment.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Existing implementation does not honor the alignment restrictions imposed
by the DMA engines. Allocate buffers with built in slack for honoring
alignment restrictions. Creating new arrays to hold the aligned pointers
and use those pointers for operations.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Commit 0d4cb44da6ca0e8 ("dmaengine: dmatest: Add support for
scatter-gather DMA mode") changes default "dmatest" behavior by
changing default mode from "memcpy" to "scatter-gather".
Now "memcpy" gets back as default mode.
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The DMA_SG is still a type of memory copy operation that should
conform the hardware restriction. So this patch just applies the
copy_align to DMA_SG as well.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Dmatest is currently including compare and fill time into the
calculated performance numbers. This does not reflect the HW
capability and the results vary based on the CPU speed instead of
the HW speed.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch updates the dmatest client to
Support scatter-gather dma mode.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Most code already uses consts for the struct kernel_param_ops,
sweep the kernel for the last offending stragglers. Other than
include/linux/moduleparam.h and kernel/params.c all other changes
were generated with the following Coccinelle SmPL patch. Merge
conflicts between trees can be handled with Coccinelle.
In the future git could get Coccinelle merge support to deal with
patch --> fail --> grammar --> Coccinelle --> new patch conflicts
automatically for us on patches where the grammar is available and
the patch is of high confidence. Consider this a feature request.
Test compiled on x86_64 against:
* allnoconfig
* allmodconfig
* allyesconfig
@ const_found @
identifier ops;
@@
const struct kernel_param_ops ops = {
};
@ const_not_found depends on !const_found @
identifier ops;
@@
-struct kernel_param_ops ops = {
+const struct kernel_param_ops ops = {
};
Generated-by: Coccinelle SmPL
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Junio C Hamano <gitster@pobox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: cocci@systeme.lip6.fr
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The scope of those varsiables is in while-loop. This patch moves them there and
removes duplicate code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Simple fixes an indentation in few places across the code.
There is no functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
1/ Step down as dmaengine maintainer see commit 08223d80df "dmaengine
maintainer update"
2/ Removal of net_dma, as it has been marked 'broken' since 3.13 (commit
7787380336 "net_dma: mark broken"), without reports of performance
regression.
3/ Miscellaneous fixes
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Merge tag 'dmaengine-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine
Pull dmaengine updates from Dan Williams:
"Even though this has fixes marked for -stable, given the size and the
needed conflict resolutions this is 3.18-rc1/merge-window material.
These patches have been languishing in my tree for a long while. The
fact that I do not have the time to do proper/prompt maintenance of
this tree is a primary factor in the decision to step down as
dmaengine maintainer. That and the fact that the bulk of drivers/dma/
activity is going through Vinod these days.
The net_dma removal has not been in -next. It has developed simple
conflicts against mainline and net-next (for-3.18).
Continuing thanks to Vinod for staying on top of drivers/dma/.
Summary:
1/ Step down as dmaengine maintainer see commit 08223d80df
"dmaengine maintainer update"
2/ Removal of net_dma, as it has been marked 'broken' since 3.13
(commit 7787380336 "net_dma: mark broken"), without reports of
performance regression.
3/ Miscellaneous fixes"
* tag 'dmaengine-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
net: make tcp_cleanup_rbuf private
net_dma: revert 'copied_early'
net_dma: simple removal
dmaengine maintainer update
dmatest: prevent memory leakage on error path in thread
ioat: Use time_before_jiffies()
dmaengine: fix xor sources continuation
dma: mv_xor: Rename __mv_xor_slot_cleanup() to mv_xor_slot_cleanup()
dma: mv_xor: Remove all callers of mv_xor_slot_cleanup()
dma: mv_xor: Remove unneeded mv_xor_clean_completed_slots() call
ioat: Use pci_enable_msix_exact() instead of pci_enable_msix()
drivers: dma: Include appropriate header file in dca.c
drivers: dma: Mark functions as static in dma_v3.c
dma: mv_xor: Add DMA API error checks
ioat/dca: Use dev_is_pci() to check whether it is pci device
When we fail to allocate memory for thread->srcs or thread->dsts and src_cnt or
dst_cnt great than 1 we leak memory on error path. This patch fixes the issue.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Prevents test result strings from being output on same line. Issue will
happen with verbose and multi-iteration modes enabled.
Signed-off-by: Jerome Blin <jerome.blin@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Pull slave-dma updates from Vinod Koul:
- new driver for BCM2835 used in R-pi
- new driver for MOXA ART
- dma_get_any_slave_channel API for DT based systems
- minor fixes and updates spread acrooss driver
[ The fsl-ssi dual fifo mode support addition clashed badly with the
other changes to fsl-ssi that came in through the sound merge. I did
a very rough cut at fixing up the conflict, but Nicolin Chen (author
of both sides) will need to verify and check things ]
* 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (36 commits)
dmaengine: mmp_pdma: fix mismerge
dma: pl08x: Export pl08x_filter_id
acpi-dma: align documentation with kernel-doc format
dma: fix vchan_cookie_complete() debug print
DMA: dmatest: extend the "device" module parameter to 32 characters
drivers/dma: fix error return code
dma: omap: Set debug level to debugging messages
dmaengine: fix kernel-doc style typos for few comments
dma: tegra: add support for Tegra148/124
dma: dw: use %pad instead of casting dma_addr_t
dma: dw: join split up messages
dma: dw: fix style of multiline comment
dmaengine: k3dma: fix sparse warnings
dma: pl330: Use dma_get_slave_channel() in the of xlate callback
dma: pl330: Differentiate between submitted and issued descriptors
dmaengine: sirf: Add device_slave_caps interface
DMA: Freescale: change BWC from 256 bytes to 1024 bytes
dmaengine: Add MOXA ART DMA engine driver
dmaengine: Add DMA_PRIVATE to BCM2835 driver
dma: imx-sdma: Assign a default script number for ROM firmware cases
...
With Device Tree a typical DMA controller device name can look like
10000000.dma-controller, which extends the current size of the string,
allocated for this parameter. This patch extends its size from 20 to 32
characters.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
drivers/dma/dmatest.c:543:11: warning: passing argument 1 of 'virt_to_phys' makes pointer from integer without a cast [enabled by default]
mips expects virt_to_phys() to take a pointer. Fix up the types accordingly.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull dmaengine changes from Dan
1/ Bartlomiej and Dan finalized a rework of the dma address unmap
implementation.
2/ In the course of testing 1/ a collection of enhancements to dmatest
fell out. Notably basic performance statistics, and fixed / enhanced
test control through new module parameters 'run', 'wait', 'noverify',
and 'verbose'. Thanks to Andriy and Linus for their review.
3/ Testing the raid related corner cases of 1/ triggered bugs in the
recently added 16-source operation support in the ioatdma driver.
4/ Some minor fixes / cleanups to mv_xor and ioatdma.
Conflicts:
drivers/dma/dmatest.c
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Verbose mode turns on test success messages, by default we only output
test summaries and failure results.
Also cleaned up some stray quotes, leftover from putting the result
message format string all on one line.
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Remove the open coded unmap and add coverage for this core functionality
to dmatest.
Also fixes up a couple places where we leaked dma mappings.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Allows for scripting test runs by module load / unload. Prevent module
load from returning until 'iterations' (finite) tests have completed, or
cause reads of the 'wait' parameter in sysfs to pause until the tests
are done.
Also killed the local waitqueue since we can just let the thread exit
naturally as long as we hold a reference.
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Add iops and throughput to the summary output.
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Towards enabling dmatest to checkout performance add a 'noverify' mode.
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
There is no need for dmatest to drain the entropy pool.
It would be nice to one day have repeatable runs, but would need a
larger rework to synchronize and order calls to the rng across test
threads.
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Currently we only test raid channels that happen to also have 'copy'
capability. Search for capable channels that do not have DMA_MEMCPY.
Note the return value from run_threaded_test never really made sense
because it could return errors after successfully starting tests. We
already have the test results per channel so missing channels can be
detected at that time.
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
1/ move 'run' control to a module parameter so we can do:
modprobe dmatest run=1. With this moved the rest of the debugfs
boilerplate can go.
2/ Fix parameter initialization. Previously the test was being started
without taking the parameters into account in the built-in case.
Also killed off the '__' version of some routines. The new rule is just
hold the lock when calling a *threaded_test() routine.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
...now that we have a common pr_fmt.
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
For long running tests the tracking results in a memory leak for the "ok"
results, and for the failures the kernel log should be sufficient. Provide a
uniform format for error messages so they can be easily parsed and remove the
debugfs file.
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This reverts commit d86b2f298e.
The kernel log buffer is sufficient for collecting test results. The
current logging OOMs the machine on long running tests, and usually only
the first error is relevant. It is better to stop on error and parse
the kernel output. If output volume becomes an issue we can always
investigate using trace messages.
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Make the driver DMA unmap also source buffers by itself
(currently it DMA unmaps only destination buffers) as
a preparation for introducing generic 'ummap' data.
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Let's move the behaviour of printing no error message back to the pre v3.10
times. It means we will use debug level in the described case, and a warning
level otherwise.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <djbw@fb.com>
There is a really little chance when we are able to create a directory and are
not able to create nodes under it. So, this patch just removes those checks.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Williams <djbw@fb.com>
The debugfs interface brought a copy of the test case parameters. This makes
different set of values under /sys/module/dmatest/parameters/ and
/sys/kernel/debug/dmatest/. The user might be confused by the divergence of
values.
The proposed solution in this patch is to make module parameters writable and
remove them from the debugfs. Though we're still using debugfs to control test
runner and getting results.
Documentation part is updated accordingly.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Dan Williams <djbw@fb.com>
Signed-off-by: Dan Williams <djbw@fb.com>
When user interrupts ongoing transfers the dmatest may end up with console
lockup, oops, or data mismatch. This patch prevents user to abort any ongoing
test.
Documentation is updated accordingly.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reported-by: Will Deacon <will.deacon@arm.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Comparison between buffers is stored to the dedicated structure.
Note that the verify result is now accessible only via file 'results' in the
debugfs.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The patch provides a storage for the test results in the linked list. The
gathered data could be used after test is done.
The new file 'results' represents gathered data of the in progress test. The
messages collected are printed to the kernel log as well.
Example of output:
% cat /sys/kernel/debug/dmatest/results
dma0chan0-copy0: #1: No errors with src_off=0x7bf dst_off=0x8ad len=0x3fea (0)
The message format is unified across the different types of errors. A number in
the parens represents additional information, e.g. error code, error counter,
or status.
Note that the buffer comparison is done in the old way, i.e. data is not
collected and just printed out.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Its meaning is to limit amount of error messages to be printed out when buffer
mismatch is occured.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The following command should return actual state of the test.
% cat /sys/kernel/debug/dmatest/run
To wait for test done the user may perform a busy loop that checks the state.
% while [ $(cat /sys/kernel/debug/dmatest/run) = "Y" ]
> do
> echo -n "."
> sleep 1
> done
> echo
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Instead of doing
modprobe dmatest ...
modprobe -r dmatest
we allow user to run tests interactively.
The dmatest could be built as module or inside kernel. Let's consider those
cases.
1. When dmatest is built as a module...
After mounting debugfs and loading the module, the /sys/kernel/debug/dmatest
folder with nodes will be created. They are the same as module parameters with
addition of the 'run' node that controls run and stop phases of the test.
Note that in this case test will not run on load automatically.
Example of usage:
% echo dma0chan0 > /sys/kernel/debug/dmatest/channel
% echo 2000 > /sys/kernel/debug/dmatest/timeout
% echo 1 > /sys/kernel/debug/dmatest/iterations
% echo 1 > /sys/kernel/debug/dmatest/run
After a while you will start to get messages about current status or error like
in the original code.
Note that running a new test will stop any in progress test.
2. When built-in in the kernel...
The module parameters that is supplied to the kernel command line will be used
for the first performed test. After user gets a control, the test could be
interrupted or re-run with same or different parameters. For the details see
the above section "1. When dmatest is built as a module..."
In both cases the module parameters are used as initial values for the test case.
You always could check them at run-time by running
% grep -H . /sys/module/dmatest/parameters/*
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Better to keep test parameters separate from internal variables.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>