On Mon, 20 Mar 2023 09:56:41 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
> We check that the PTF instruction is working correctly when
> the cpu topology facility is available.
>
> For KVM only, we test changing of the polarity between horizontal
> and vertical and that a reset set the horizontal polarity.
>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> ---
> s390x/Makefile | 1 +
> s390x/topology.c | 180 ++++++++++++++++++++++++++++++++++++++++++++
> s390x/unittests.cfg | 3 +
> 3 files changed, 184 insertions(+)
> create mode 100644 s390x/topology.c
>
> diff --git a/s390x/Makefile b/s390x/Makefile
> index e94b720..05dac04 100644
> --- a/s390x/Makefile
> +++ b/s390x/Makefile
> @@ -40,6 +40,7 @@ tests += $(TEST_DIR)/panic-loop-pgm.elf
> tests += $(TEST_DIR)/migration-sck.elf
> tests += $(TEST_DIR)/exittime.elf
> tests += $(TEST_DIR)/ex.elf
> +tests += $(TEST_DIR)/topology.elf
>
> pv-tests += $(TEST_DIR)/pv-diags.elf
>
> diff --git a/s390x/topology.c b/s390x/topology.c
> new file mode 100644
> index 0000000..ce248f1
> --- /dev/null
> +++ b/s390x/topology.c
> @@ -0,0 +1,180 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * CPU Topology
> + *
> + * Copyright IBM Corp. 2022
> + *
> + * Authors:
> + * Pierre Morel <pmorel@xxxxxxxxxxxxx>
> + */
> +
> +#include <libcflat.h>
> +#include <asm/page.h>
> +#include <asm/asm-offsets.h>
> +#include <asm/interrupt.h>
> +#include <asm/facility.h>
> +#include <smp.h>
> +#include <sclp.h>
> +#include <s390x/hardware.h>
> +
> +#define PTF_REQ_HORIZONTAL 0
> +#define PTF_REQ_VERTICAL 1
> +#define PTF_REQ_CHECK 2
> +
> +#define PTF_ERR_NO_REASON 0
> +#define PTF_ERR_ALRDY_POLARIZED 1
> +#define PTF_ERR_IN_PROGRESS 2
> +
> +extern int diag308_load_reset(u64);
> +
> +static int ptf(unsigned long fc, unsigned long *rc)
> +{
> + int cc;
> +
> + asm volatile(
> + " ptf %1 \n"
> + " ipm %0 \n"
> + " srl %0,28 \n"
> + : "=d" (cc), "+d" (fc)
> + :
> + : "cc");
> +
> + *rc = fc >> 8;
> + return cc;
> +}
> +
> +static void check_privilege(int fc)
> +{
> + unsigned long rc;
> +
> + report_prefix_push("Privilege");
> + report_info("function code %d", fc);
> + enter_pstate();
> + expect_pgm_int();
> + ptf(fc, &rc);
> + check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
> + report_prefix_pop();
> +}
> +
> +static void check_function_code(void)
> +{
> + unsigned long rc;
> +
> + report_prefix_push("Undefined fc");
> + expect_pgm_int();
> + ptf(0xff, &rc);
please don't use magic numbers, add a new macro PTF_INVALID_FUNCTION
(or something like that)
> + check_pgm_int_code(PGM_INT_CODE_SPECIFICATION);
> + report_prefix_pop();
> +}
> +
> +static void check_reserved_bits(void)
> +{
> + unsigned long rc;
> +
> + report_prefix_push("Reserved bits");
> + expect_pgm_int();
> + ptf(0xffffffffffffff00UL, &rc);
I would like every single bit to be tested, since all of them are
required to be zero.
make a loop and test each, but please report success of failure only
once at the end.
use a report_info in case of failure to indicate which bit failed
> + check_pgm_int_code(PGM_INT_CODE_SPECIFICATION);
> + report_prefix_pop();
> +}
> +
> +static void check_mtcr_pending(void)
> +{
> + unsigned long rc;
> + int cc;
> +
> + report_prefix_push("Topology Report pending");
> + /*
> + * At this moment the topology may already have changed
> + * since the VM has been started.
> + * However, we can test if a second PTF instruction
> + * reports that the topology did not change since the
> + * preceding PFT instruction.
> + */
> + ptf(PTF_REQ_CHECK, &rc);
> + cc = ptf(PTF_REQ_CHECK, &rc);
> + report(cc == 0, "PTF check should clear topology report");
> + report_prefix_pop();
> +}
> +
> +static void check_polarization_change(void)
> +{
> + unsigned long rc;
> + int cc;
> +
> + report_prefix_push("Topology polarization check");
> +
> + /* We expect a clean state through reset */
> + report(diag308_load_reset(1), "load normal reset done");
> +
> + /*
> + * Set vertical polarization to verify that RESET sets
> + * horizontal polarization back.
> + */
> + cc = ptf(PTF_REQ_VERTICAL, &rc);
> + report(cc == 0, "Set vertical polarization.");
> +
> + report(diag308_load_reset(1), "load normal reset done");
> +
> + cc = ptf(PTF_REQ_CHECK, &rc);
> + report(cc == 0, "Reset should clear topology report");
> +
> + cc = ptf(PTF_REQ_HORIZONTAL, &rc);
> + report(cc == 2 && rc == PTF_ERR_ALRDY_POLARIZED,
> + "After RESET polarization is horizontal");
> +
> + /* Flip between vertical and horizontal polarization */
> + cc = ptf(PTF_REQ_VERTICAL, &rc);
> + report(cc == 0, "Change to vertical polarization.");
either here or in a new block, test that setting vertical twice in
a row will also result in a cc == 2 && rc == PTF_ERR_ALRDY_POLARIZED
> +
> + cc = ptf(PTF_REQ_CHECK, &rc);
> + report(cc == 1, "Polarization change should set topology report");
> +
> + cc = ptf(PTF_REQ_HORIZONTAL, &rc);
> + report(cc == 0, "Change to horizontal polarization.");
it cannot hurt to add here another check for pending reports
> +
> + report_prefix_pop();
> +}
> +
> +static void test_ptf(void)
> +{
> + check_privilege(PTF_REQ_HORIZONTAL);
> + check_privilege(PTF_REQ_VERTICAL);
> + check_privilege(PTF_REQ_CHECK);
> + check_function_code();
> + check_reserved_bits();
> + check_mtcr_pending();
> + check_polarization_change();
> +}
> +
> +static struct {
> + const char *name;
> + void (*func)(void);
> +} tests[] = {
> + { "PTF", test_ptf},
> + { NULL, NULL }
> +};
> +
> +int main(int argc, char *argv[])
> +{
> + int i;
> +
> + report_prefix_push("CPU Topology");
> +
> + if (!test_facility(11)) {
> + report_skip("Topology facility not present");
> + goto end;
> + }
> +
> + report_info("Virtual machine level %ld", stsi_get_fc());
> +
> + for (i = 0; tests[i].name; i++) {
> + report_prefix_push(tests[i].name);
> + tests[i].func();
> + report_prefix_pop();
> + }
> +
> +end:
> + report_prefix_pop();
> + return report_summary();
> +}
> diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
> index 453ee9c..d0ac683 100644
> --- a/s390x/unittests.cfg
> +++ b/s390x/unittests.cfg
> @@ -233,3 +233,6 @@ extra_params = -append '--parallel'
>
> [execute]
> file = ex.elf
> +
> +[topology]
> +file = topology.elf
