This patch includes all of the powerpc test binaries into the .gitignore
file listing in their respective directories. This will make sure that
git ignores all of these test binaries when displaying status.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Although we expect some small discrepancies for very large counts, we
seem to be able to count up to 64 billion instructions without too much
skew, so do so.
Also switch to using decimals for the instruction counts. This just
makes it easier to visually compare the expected vs actual values, as
well as the raw result from instructions.
Before:
instructions: result 68719476753 running/enabled 13101961654
cycles: result 38077343785 running/enabled 13101725752
Looped for 68719476736 instructions, overhead 17
Expected 68719476753
Actual 68719476753
Delta 0, 0.000000%
success: count_instructions
After:
instructions: result 64000000016 running/enabled 12197599964
cycles: result 35412471674 running/enabled 12197534110
Looped for 64000000000 instructions, overhead 16
Expected 64000000016
Actual 64000000016
Delta 0, 0.000000%
success: count_instructions
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Have a task eat some cpu while we are counting instructions to create
some scheduler pressure. The idea being to try and unearth any bugs we
have in counting that only appear when context switching is happening.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There is at least one bug in core_busy_loop(), we use r0, but it's
not in the clobber list. We were getting away with this it seems but
that was luck.
It's also fishy to be touching the stack, even if we do it below the
stack pointer. It seems we get away with it, but looking at the
generated code that may just be luck.
So move it into assembler, do all the stack handling by hand. We create
a stack frame to save the non-volatiles in, so we can muck around with
them.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently we ignore errors from our sub Makefiles. We inherited that
from the top-level selftests Makefile which aims to build and run as
many tests as possible and damn the torpedoes.
For the powerpc tests we'd instead like any errors to fail the build, so
we can automatically catch build failures.
We can achieve the best of both worlds by using -k, which tells make to
keep building when it hits an error, but still reports the error.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The Power8 Performance Monitor Unit (PMU) has a new feature called Event
Based Branches (EBB). This commit adds tests of the kernel API for using
EBBs.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit adds a test of instruction counting using the PMU on powerpc.
Although the bulk of the code is architecture agnostic, the code needs to
run a precisely sized loop which is implemented in assembler.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
