[PATCH v4 2/2] powerpc/selftests/copyloops: extend selftest to exercise __copy_tofrom_user_power7_vmx

[Venkat Rao Bagalkote]

On 04/03/26 5:52 pm, Sayali Patil wrote:
> The new PowerPC VMX fast path (__copy_tofrom_user_power7_vmx) is not
> exercised by existing copyloops selftests. This patch updates
> the selftest to exercise the VMX variant, ensuring the VMX copy path
> is validated.
>
> Changes include:
>    - COPY_LOOP=test___copy_tofrom_user_power7_vmx with -D VMX_TEST is used
>      in existing selftest build targets.
>    - Inclusion of ../utils.c to provide get_auxv_entry() for hardware
>      feature detection.
>    - At runtime, the test skips execution if Altivec is not available.
>    - Copy sizes above VMX_COPY_THRESHOLD are used to ensure the VMX
>      path is taken.
>
> This enables validation of the VMX fast path without affecting systems
> that do not support Altivec.
>
> Signed-off-by: Sayali Patil <sayalip at linux.ibm.com>
> ---


Tested-by: Venkat Rao Bagalkote <venkat88 at linux.ibm.com>


# timeout set to 130
# selftests: powerpc/copyloops: copyuser_p7
# test: test___copy_tofrom_user_power7
# tags: git_version:v7.0-rc2-92-gb7b2ed2d96ea
# success: test___copy_tofrom_user_power7
ok 4 selftests: powerpc/copyloops: copyuser_p7
# timeout set to 130
# selftests: powerpc/copyloops: copyuser_p7_vmx
# test: test___copy_tofrom_user_power7_vmx
# tags: git_version:v7.0-rc2-92-gb7b2ed2d96ea
# success: test___copy_tofrom_user_power7_vmx


Regards,

Venkat.

>
> v3->v4
> No changes in the patch.
>
> v3: https://lore.kernel.org/all/20260304053506.118632-2-sayalip@linux.ibm.com/
>
> ---
>   .../selftests/powerpc/copyloops/.gitignore        |  4 ++--
>   .../testing/selftests/powerpc/copyloops/Makefile  | 11 ++++++++---
>   tools/testing/selftests/powerpc/copyloops/stubs.S |  8 --------
>   .../selftests/powerpc/copyloops/validate.c        | 15 ++++++++++++++-
>   4 files changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/tools/testing/selftests/powerpc/copyloops/.gitignore b/tools/testing/selftests/powerpc/copyloops/.gitignore
> index 7283e8b07b75..80d4270a71ac 100644
> --- a/tools/testing/selftests/powerpc/copyloops/.gitignore
> +++ b/tools/testing/selftests/powerpc/copyloops/.gitignore
> @@ -2,8 +2,8 @@
>   copyuser_64_t0
>   copyuser_64_t1
>   copyuser_64_t2
> -copyuser_p7_t0
> -copyuser_p7_t1
> +copyuser_p7
> +copyuser_p7_vmx
>   memcpy_64_t0
>   memcpy_64_t1
>   memcpy_64_t2
> diff --git a/tools/testing/selftests/powerpc/copyloops/Makefile b/tools/testing/selftests/powerpc/copyloops/Makefile
> index 42940f92d832..0c8efb0bddeb 100644
> --- a/tools/testing/selftests/powerpc/copyloops/Makefile
> +++ b/tools/testing/selftests/powerpc/copyloops/Makefile
> @@ -1,6 +1,6 @@
>   # SPDX-License-Identifier: GPL-2.0
>   TEST_GEN_PROGS := copyuser_64_t0 copyuser_64_t1 copyuser_64_t2 \
> -		copyuser_p7_t0 copyuser_p7_t1 \
> +		copyuser_p7 copyuser_p7_vmx \
>   		memcpy_64_t0 memcpy_64_t1 memcpy_64_t2 \
>   		memcpy_p7_t0 memcpy_p7_t1 copy_mc_64 \
>   		copyuser_64_exc_t0 copyuser_64_exc_t1 copyuser_64_exc_t2 \
> @@ -28,10 +28,15 @@ $(OUTPUT)/copyuser_64_t%:	copyuser_64.S $(EXTRA_SOURCES)
>   		-D SELFTEST_CASE=$(subst copyuser_64_t,,$(notdir $@)) \
>   		-o $@ $^
>   
> -$(OUTPUT)/copyuser_p7_t%:	copyuser_power7.S $(EXTRA_SOURCES)
> +$(OUTPUT)/copyuser_p7:	copyuser_power7.S $(EXTRA_SOURCES)
>   	$(CC) $(CPPFLAGS) $(CFLAGS) \
>   		-D COPY_LOOP=test___copy_tofrom_user_power7 \
> -		-D SELFTEST_CASE=$(subst copyuser_p7_t,,$(notdir $@)) \
> +		-o $@ $^
> +
> +$(OUTPUT)/copyuser_p7_vmx:       copyuser_power7.S $(EXTRA_SOURCES) ../utils.c
> +	$(CC) $(CPPFLAGS) $(CFLAGS) \
> +		-D COPY_LOOP=test___copy_tofrom_user_power7_vmx \
> +		-D VMX_TEST \
>   		-o $@ $^
>   
>   # Strictly speaking, we only need the memcpy_64 test cases for big-endian
> diff --git a/tools/testing/selftests/powerpc/copyloops/stubs.S b/tools/testing/selftests/powerpc/copyloops/stubs.S
> index ec8bcf2bf1c2..3a9cb8c9a3ee 100644
> --- a/tools/testing/selftests/powerpc/copyloops/stubs.S
> +++ b/tools/testing/selftests/powerpc/copyloops/stubs.S
> @@ -1,13 +1,5 @@
>   #include <asm/ppc_asm.h>
>   
> -FUNC_START(enter_vmx_usercopy)
> -	li	r3,1
> -	blr
> -
> -FUNC_START(exit_vmx_usercopy)
> -	li	r3,0
> -	blr
> -
>   FUNC_START(enter_vmx_ops)
>   	li	r3,1
>   	blr
> diff --git a/tools/testing/selftests/powerpc/copyloops/validate.c b/tools/testing/selftests/powerpc/copyloops/validate.c
> index 0f6873618552..fb822534fbe9 100644
> --- a/tools/testing/selftests/powerpc/copyloops/validate.c
> +++ b/tools/testing/selftests/powerpc/copyloops/validate.c
> @@ -12,6 +12,10 @@
>   #define BUFLEN (MAX_LEN+MAX_OFFSET+2*MIN_REDZONE)
>   #define POISON 0xa5
>   
> +#ifdef VMX_TEST
> +#define VMX_COPY_THRESHOLD 3328
> +#endif
> +
>   unsigned long COPY_LOOP(void *to, const void *from, unsigned long size);
>   
>   static void do_one(char *src, char *dst, unsigned long src_off,
> @@ -81,8 +85,12 @@ int test_copy_loop(void)
>   	/* Fill with sequential bytes */
>   	for (i = 0; i < BUFLEN; i++)
>   		fill[i] = i & 0xff;
> -
> +#ifdef VMX_TEST
> +	/* Force sizes above kernel VMX threshold (3328) */
> +	for (len = VMX_COPY_THRESHOLD + 1; len < MAX_LEN; len++) {
> +#else
>   	for (len = 1; len < MAX_LEN; len++) {
> +#endif
>   		for (src_off = 0; src_off < MAX_OFFSET; src_off++) {
>   			for (dst_off = 0; dst_off < MAX_OFFSET; dst_off++) {
>   				do_one(src, dst, src_off, dst_off, len,
> @@ -96,5 +104,10 @@ int test_copy_loop(void)
>   
>   int main(void)
>   {
> +#ifdef VMX_TEST
> +	/* Skip if Altivec not present */
> +	SKIP_IF_MSG(!have_hwcap(PPC_FEATURE_HAS_ALTIVEC), "ALTIVEC not supported");
> +#endif
> +
>   	return test_harness(test_copy_loop, str(COPY_LOOP));
>   }