Since it's likely to be useful for performance work with SVE let's have a
pidbench that gives us some numbers for consideration. In order to ensure
that we test exactly the scenario we want this is written in assembly - if
system libraries use SVE this would stop us exercising the case where the
process has never used SVE.
We exercise three cases:
- Never having used SVE.
- Having used SVE once.
- Using SVE after each syscall.
by spinning running getpid() for a fixed number of iterations with the
time measured using CNTVCT_EL0 reported on the console. This is obviously
a totally unrealistic benchmark which will show the extremes of any
performance variation but equally given the potential gotchas with use of
FP instructions by system libraries it's good to have some concrete code
shared to make it easier to compare notes on results.
Testing over multiple SVE vector lengths will need to be done with vlset
currently, the test could be extended to iterate over all of them if
desired.
Signed-off-by: Mark Brown <broonie(a)kernel.org>
---
tools/testing/selftests/arm64/fp/.gitignore | 1 +
tools/testing/selftests/arm64/fp/Makefile | 4 +-
.../testing/selftests/arm64/fp/fp-pidbench.S | 71 +++++++++++++++++++
3 files changed, 75 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/arm64/fp/fp-pidbench.S
diff --git a/tools/testing/selftests/arm64/fp/.gitignore b/tools/testing/selftests/arm64/fp/.gitignore
index b67395903b9b..c50d86331ed2 100644
--- a/tools/testing/selftests/arm64/fp/.gitignore
+++ b/tools/testing/selftests/arm64/fp/.gitignore
@@ -1,3 +1,4 @@
+fp-pidbench
fpsimd-test
rdvl-sve
sve-probe-vls
diff --git a/tools/testing/selftests/arm64/fp/Makefile b/tools/testing/selftests/arm64/fp/Makefile
index ba1488c7c315..95f0b877a060 100644
--- a/tools/testing/selftests/arm64/fp/Makefile
+++ b/tools/testing/selftests/arm64/fp/Makefile
@@ -2,13 +2,15 @@
CFLAGS += -I../../../../../usr/include/
TEST_GEN_PROGS := sve-ptrace sve-probe-vls vec-syscfg
-TEST_PROGS_EXTENDED := fpsimd-test fpsimd-stress \
+TEST_PROGS_EXTENDED := fp-pidbench fpsimd-test fpsimd-stress \
rdvl-sve \
sve-test sve-stress \
vlset
all: $(TEST_GEN_PROGS) $(TEST_PROGS_EXTENDED)
+fp-pidbench: fp-pidbench.S asm-utils.o
+ $(CC) -nostdlib $^ -o $@
fpsimd-test: fpsimd-test.o asm-utils.o
$(CC) -nostdlib $^ -o $@
rdvl-sve: rdvl-sve.o rdvl.o
diff --git a/tools/testing/selftests/arm64/fp/fp-pidbench.S b/tools/testing/selftests/arm64/fp/fp-pidbench.S
new file mode 100644
index 000000000000..16a436389bfc
--- /dev/null
+++ b/tools/testing/selftests/arm64/fp/fp-pidbench.S
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2021 ARM Limited.
+// Original author: Mark Brown <broonie(a)kernel.org>
+//
+// Trivial syscall overhead benchmark.
+//
+// This is implemented in asm to ensure that we don't have any issues with
+// system libraries using instructions that disrupt the test.
+
+#include <asm/unistd.h>
+#include "assembler.h"
+
+.arch_extension sve
+
+.macro test_loop per_loop
+ mov x10, x20
+ mov x8, #__NR_getpid
+ mrs x11, CNTVCT_EL0
+1:
+ \per_loop
+ svc #0
+ sub x10, x10, #1
+ cbnz x10, 1b
+
+ mrs x12, CNTVCT_EL0
+ sub x0, x12, x11
+ bl putdec
+ puts "\n"
+.endm
+
+// Main program entry point
+.globl _start
+function _start
+_start:
+ puts "Iterations per test: "
+ mov x20, #10000
+ lsl x20, x20, #8
+ mov x0, x20
+ bl putdec
+ puts "\n"
+
+ // Test having never used SVE
+ puts "No SVE: "
+ test_loop
+
+ // Check for SVE support - should use hwcap but that's hard in asm
+ mrs x0, ID_AA64PFR0_EL1
+ ubfx x0, x0, #32, #4
+ cbnz x0, 1f
+ puts "System does not support SVE\n"
+ b out
+1:
+
+ // Execute a SVE instruction
+ puts "SVE VL: "
+ rdvl x0, #8
+ bl putdec
+ puts "\n"
+
+ puts "SVE used once: "
+ test_loop
+
+ // Use SVE per syscall
+ puts "SVE used per syscall: "
+ test_loop "rdvl x0, #8"
+
+ // And we're done
+out:
+ mov x0, #0
+ mov x8, #__NR_exit
+ svc #0
--
2.30.2
Hi all,
Today's linux-next merge of the xarray tree got a conflict in:
tools/include/linux/kernel.h
between commits:
d6e6a27d960f9 ("tools: Fix math.h breakage")
066b34aa5461f ("tools: fix ARRAY_SIZE defines in tools and selftests hdrs")
from the kselftest and origin trees and commit:
f2aa11fd51440 ("tools: Fix math.h breakage")
from the xarray tree.
I fixed it up (see below) and can carry the fix as necessary. This
is now fixed as far as linux-next is concerned, but any non trivial
conflicts should be mentioned to your upstream maintainer when your tree
is submitted for merging. You may also want to consider cooperating
with the maintainer of the conflicting tree to minimise any particularly
complex conflicts.
diff --cc tools/include/linux/kernel.h
index 9701e8307db02,3e8df500cfbd4..0000000000000
--- a/tools/include/linux/kernel.h
+++ b/tools/include/linux/kernel.h
Dzień dobry,
dostrzegam możliwość współpracy z Państwa firmą.
Świadczymy kompleksową obsługę inwestycji w fotowoltaikę, która obniża koszty energii elektrycznej nawet o 90%.
Czy są Państwo zainteresowani weryfikacją wstępnych propozycji?
Pozdrawiam,
Mateusz Adamczyk
Commit f0ff2447b861 ("selftests/sgx: Add a new kselftest:
Unclobbered_vdso_oversubscribed") depends on __cpuid() without
providing the dependency and thus introduces a build error:
$ make
gcc -Wall -Werror -g -I../../../../tools/include -fPIC -z noexecstack -c main.c -o /path/linux/tools/testing/selftests/sgx/main.o
main.c: In function ‘get_total_epc_mem’:
main.c:296:3: error: implicit declaration of function ‘__cpuid’ [-Werror=implicit-function-declaration]
296 | __cpuid(&eax, &ebx, &ecx, &edx);
| ^~~~~~~
cc1: all warnings being treated as errors
make: *** [Makefile:33: /path/linux/tools/testing/selftests/sgx/main.o] Error 1
$
Make the kernel's __cpuid() available locally in support of the
test's usage.
Fixes: f0ff2447b861 ("selftests/sgx: Add a new kselftest: Unclobbered_vdso_oversubscribed")
Reported-by: Jarkko Sakkinen <jarkko(a)kernel.org>
Signed-off-by: Reinette Chatre <reinette.chatre(a)intel.com>
---
The commit introducing the issue can be found on
the x86/sgx branch of tip.git.
tools/testing/selftests/sgx/main.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/tools/testing/selftests/sgx/main.c b/tools/testing/selftests/sgx/main.c
index 7e912db4c6c5..6dead57a3121 100644
--- a/tools/testing/selftests/sgx/main.c
+++ b/tools/testing/selftests/sgx/main.c
@@ -73,6 +73,18 @@ static bool vdso_get_symtab(void *addr, struct vdso_symtab *symtab)
return true;
}
+static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
+ unsigned int *ecx, unsigned int *edx)
+{
+ asm volatile("cpuid"
+ : "=a" (*eax),
+ "=b" (*ebx),
+ "=c" (*ecx),
+ "=d" (*edx)
+ : "0" (*eax), "2" (*ecx)
+ : "memory");
+}
+
static unsigned long elf_sym_hash(const char *name)
{
unsigned long h = 0, high;
--
2.25.1
'==' is a bashisms and not understood by POSIX shell. Drop it from
gpio-sim selftests.
Signed-off-by: Bartosz Golaszewski <brgl(a)bgdev.pl>
---
I ran the newly applied patches on a different system and noticed the
tests now fail. I missed '==' operators for string comparison I used in
some places.
tools/testing/selftests/gpio/gpio-sim.sh | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/gpio/gpio-sim.sh b/tools/testing/selftests/gpio/gpio-sim.sh
index d335a975890c..c913d5aec768 100755
--- a/tools/testing/selftests/gpio/gpio-sim.sh
+++ b/tools/testing/selftests/gpio/gpio-sim.sh
@@ -23,12 +23,12 @@ remove_chip() {
for FILE in $CONFIGFS_DIR/$CHIP/*; do
BANK=`basename $FILE`
- if [ "$BANK" == "live" ] || [ "$BANK" == "dev_name" ]; then
+ if [ "$BANK" = "live" ] || [ "$BANK" = "dev_name" ]; then
continue
fi
LINES=`ls $CONFIGFS_DIR/$CHIP/$BANK/ | egrep ^line`
- if [ "$?" == 0 ]; then
+ if [ "$?" = 0 ]; then
for LINE in $LINES; do
if [ -e $CONFIGFS_DIR/$CHIP/$BANK/$LINE/hog ]; then
rmdir $CONFIGFS_DIR/$CHIP/$BANK/$LINE/hog || \
--
2.30.1