Currently we log the creation of the child process as a test but it's not
really relevant to what we're trying to test and can make the output a
little confusing so don't do that.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210913125505.52619-3-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Partly in preparation for future refactoring move from hard coding the
number of tests in main() to putting #define at the top of the source
instead.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210913125505.52619-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Write down some ideas for additional coverage for floating point in case
someone feels inspired to look into them.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/20210803140450.46624-5-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
We provide interfaces for configuring the SVE vector length seen by
processes using prctl and also via /proc for configuring the default
values. Provide tests that exercise all these interfaces and verify that
they take effect as expected, though at present no test fully enumerates
all the possible vector lengths.
A subset of this is already tested via sve-probe-vls but the /proc
interfaces are not currently covered at all.
In preparation for the forthcoming support for SME, the Scalable Matrix
Extension, which has separately but similarly configured vector lengths
which we expect to offer similar userspace interfaces for, all the actual
files and prctls used are parameterised and we don't validate that the
architectural minimum vector length is the minimum we see.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/20210803140450.46624-4-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Currently sve-probe-vls does not verify that the vector lengths reported
by the prctl() interface are actually what is reported by the architecture,
use the rdvl_sve() helper to validate this.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/20210803140450.46624-3-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
SVE provides an instruction RDVL which reports the currently configured
vector length. In order to validate that our vector length configuration
interfaces are working correctly without having to build the C code for
our test programs with SVE enabled provide a trivial assembly library
with a C callable function that executes RDVL. Since these interfaces
also control behaviour on exec*() provide a trivial wrapper program which
reports the currently configured vector length on stdout, tests can use
this to verify that behaviour on exec*() is as expected.
In preparation for providing similar helper functionality for SME, the
Scalable Matrix Extension, which allows separately configured vector
lengths to be read back both the assembler function and wrapper binary
have SVE included in their name.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/20210803140450.46624-2-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The "First Fault Register" (FFR) is an SVE register that mimics a
predicate register, but clears bits when a load or store fails to handle
an element of a vector. The supposed usage scenario is to initialise
this register (using SETFFR), then *read* it later on to learn about
elements that failed to load or store. Explicit writes to this register
using the WRFFR instruction are only supposed to *restore* values
previously read from the register (for context-switching only).
As the manual describes, this register holds only certain values, it:
"... contains a monotonic predicate value, in which starting from bit 0
there are zero or more 1 bits, followed only by 0 bits in any remaining
bit positions."
Any other value is UNPREDICTABLE and is not supposed to be "restored"
into the register.
The SVE test currently tries to write a signature pattern into the
register, which is *not* a canonical FFR value. Apparently the existing
setups treat UNPREDICTABLE as "read-as-written", but a new
implementation actually only stores canonical values. As a consequence,
the sve-test fails immediately when comparing the FFR value:
-----------
# ./sve-test
Vector length: 128 bits
PID: 207
Mismatch: PID=207, iteration=0, reg=48
Expected [cf00]
Got [0f00]
Aborted
-----------
Fix this by only populating the FFR with proper canonical values.
Effectively the requirement described above limits us to 17 unique
values over 16 bits worth of FFR, so we condense our signature down to 4
bits (2 bits from the PID, 2 bits from the generation) and generate the
canonical pattern from it. Any bits describing elements above the
minimum 128 bit are set to 0.
This aligns the FFR usage to the architecture and fixes the test on
microarchitectures implementing FFR in a more restricted way.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviwed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210319120128.29452-1-andre.przywara@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
We track if sve-ptrace encountered a failure in a variable but don't
actually use that value when we exit the program, do so.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210309190304.39169-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Integrate the FP tests with the build system and add some documentation
for the ones run outside the kselftest infrastructure. The content in
the README was largely written by Dave Martin with edits by me.
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200819114837.51466-7-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Add wrapper scripts which invoke fpsimd-test and sve-test with several
copies per CPU such that the context switch code will be appropriately
exercised.
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200819114837.51466-6-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
vlset is a small utility for use in conjunction with tests like the sve-test
stress test which allows another executable to be invoked with a configured
SVE vector length.
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200819114837.51466-5-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Add programs sve-test and fpsimd-test which spin reading and writing to
the SVE and FPSIMD registers, verifying the operations they perform. The
intended use is to leave them running to stress the context switch code's
handling of these registers which isn't compatible with what kselftest
does so they're not integrated into the framework but there's no other
obvious testsuite where they fit so let's store them here.
These tests were written by Dave Martin and lightly adapted by me.
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200819114837.51466-4-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Add a test case that does some basic verification of the SVE ptrace
interface, forking off a child with known values in the registers and
then using ptrace to inspect and manipulate the SVE registers of the
child, including in FPSIMD mode to account for sharing between the SVE
and FPSIMD registers.
This program was written by Dave Martin and modified for kselftest by
me.
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200819114837.51466-3-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Add a test case that verifies that we can enumerate the SVE vector lengths
on systems where we detect SVE, and that those SVE vector lengths are
valid. This program was written by Dave Martin and adapted to kselftest by
me.
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200819114837.51466-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
