Re: [kvm-unit-tests PATCH v3 11/14] arm/arm64: ITS: INT functional tests

[Auger Eric]

Hi Drew,

On 2/7/20 2:15 PM, Andrew Jones wrote:
> On Tue, Jan 28, 2020 at 11:34:56AM +0100, Eric Auger wrote:
>> Triggers LPIs through the INT command.
>>
>> the test checks the LPI hits the right CPU and triggers
>> the right LPI intid, ie. the translation is correct.
>>
>> Updates to the config table also are tested, along with inv
>> and invall commands.
>>
>> Signed-off-by: Eric Auger <address@hidden>
>>
>> ---
>>
>> v2 -> v3:
>> - add comments
>> - keep the report_skip in case there aren't 4 vcpus to be able to
>>   run other tests in the its category.
>> - fix the prefix pop
>> - move its_event and its_stats to arm/gic.c
>> ---
>>  arm/gic.c         | 228 +++++++++++++++++++++++++++++++++++++++++++---
>>  arm/unittests.cfg |   7 ++
>>  2 files changed, 224 insertions(+), 11 deletions(-)
>>
>> diff --git a/arm/gic.c b/arm/gic.c
>> index 4d7dd03..50104b1 100644
>> --- a/arm/gic.c
>> +++ b/arm/gic.c
>> @@ -160,6 +160,87 @@ static void ipi_handler(struct pt_regs *regs __unused)
>>      }
>>  }
>>  
>> +static void setup_irq(handler_t handler)
>> +{
>> +    gic_enable_defaults();
>> +#ifdef __arm__
>> +    install_exception_handler(EXCPTN_IRQ, handler);
>> +#else
>> +    install_irq_handler(EL1H_IRQ, handler);
>> +#endif
>> +    local_irq_enable();
>> +}
>> +
>> +#if defined(__aarch64__)
>> +struct its_event {
>> +    int cpu_id;
>> +    int lpi_id;
>> +};
>> +
>> +struct its_stats {
>> +    struct its_event expected;
>> +    struct its_event observed;
>> +};
>> +
>> +static struct its_stats lpi_stats;
>> +
>> +static void lpi_handler(struct pt_regs *regs __unused)
>> +{
>> +    u32 irqstat = gic_read_iar();
>> +    int irqnr = gic_iar_irqnr(irqstat);
>> +
>> +    gic_write_eoir(irqstat);
>> +    if (irqnr < 8192)
>> +            report(false, "Unexpected non LPI interrupt received");
> 
> report_info
why? This is an error case. We do not expect other interrupts than LPIs
> 
>> +    smp_rmb(); /* pairs with wmb in lpi_stats_expect */
>> +    lpi_stats.observed.cpu_id = smp_processor_id();
>> +    lpi_stats.observed.lpi_id = irqnr;
>> +    smp_wmb(); /* pairs with rmb in check_lpi_stats */
>> +}
>> +
>> +static void lpi_stats_expect(int exp_cpu_id, int exp_lpi_id)
>> +{
>> +    lpi_stats.expected.cpu_id = exp_cpu_id;
>> +    lpi_stats.expected.lpi_id = exp_lpi_id;
>> +    lpi_stats.observed.cpu_id = -1;
>> +    lpi_stats.observed.lpi_id = -1;
>> +    smp_wmb(); /* pairs with rmb in handler */
>> +}
>> +
>> +static void check_lpi_stats(void)
> 
> static void check_lpi_stats(const char *testname)
> {
>    bool pass = false;
> 
>> +{
>> +    mdelay(100);
>> +    smp_rmb(); /* pairs with wmb in lpi_handler */
>> +    if ((lpi_stats.observed.cpu_id != lpi_stats.expected.cpu_id) ||
>> +        (lpi_stats.observed.lpi_id != lpi_stats.expected.lpi_id)) {
> 
> nit: extra ()
> 
>> +            if (lpi_stats.observed.cpu_id == -1 &&
>> +                lpi_stats.observed.lpi_id == -1) {
>> +                    report(false,
>> +                           "No LPI received whereas (cpuid=%d, intid=%d) "
>> +                           "was expected", lpi_stats.expected.cpu_id,
>> +                           lpi_stats.expected.lpi_id);
> 
> report_info
What's the problem keeping those. Those are error reports. The message
is something like that:
FAIL: gicv3: its-trigger: mapc valid=false: No LPI received whereas
(cpuid=1, intid=8192) was expected.

So the testname is already part of the message.
> 
>> +            } else {
>> +                    report(false, "Unexpected LPI (cpuid=%d, intid=%d)",
>> +                           lpi_stats.observed.cpu_id,
>> +                           lpi_stats.observed.lpi_id);
> 
> report_info
> 
>> +            }
> 
> pass = false;
> 
>> +    } else if (lpi_stats.expected.lpi_id != -1) {
>> +            report(true, "LPI %d on CPU %d", lpi_stats.observed.lpi_id,
>> +                   lpi_stats.observed.cpu_id);
> 
> report_info
> 
>> +    } else {
>> +            report(true, "no LPI received, as expected");
> 
> report_info
> 
> 
>> +    }
> 
> report(pass, "%s", testname);
> 
>> +}
>> +
>> +static void secondary_lpi_test(void)
>> +{
>> +    setup_irq(lpi_handler);
>> +    cpumask_set_cpu(smp_processor_id(), &ready);
>> +    while (1)
>> +            wfi();
>> +}
>> +#endif
>> +
>>  static void gicv2_ipi_send_self(void)
>>  {
>>      writel(2 << 24 | IPI_IRQ, gicv2_dist_base() + GICD_SGIR);
>> @@ -217,17 +298,6 @@ static void ipi_test_smp(void)
>>      report_prefix_pop();
>>  }
>>  
>> -static void setup_irq(handler_t handler)
>> -{
>> -    gic_enable_defaults();
>> -#ifdef __arm__
>> -    install_exception_handler(EXCPTN_IRQ, handler);
>> -#else
>> -    install_irq_handler(EL1H_IRQ, handler);
>> -#endif
>> -    local_irq_enable();
>> -}
>> -
>>  static void ipi_send(void)
>>  {
>>      setup_irq(ipi_handler);
>> @@ -522,6 +592,7 @@ static void gic_test_mmio(void)
>>  #if defined(__arm__)
>>  
>>  static void test_its_introspection(void) {}
>> +static void test_its_trigger(void) {}
>>  
>>  #else /* __arch64__ */
>>  
>> @@ -561,6 +632,137 @@ static void test_its_introspection(void)
>>      report_info("collection baser entry_size = 0x%x", coll_baser->esz);
>>  }
>>  
>> +static bool its_prerequisites(int nb_cpus)
>> +{
>> +    int cpu;
>> +
>> +    if (!gicv3_its_base()) {
>> +            report_skip("No ITS, skip ...");
>> +            return true;
>> +    }
>> +
>> +    if (nr_cpus < 4) {
> 
> nr_cpus < nb_cpus, or just drop the nb_cpus parameter and hard code 4
> here.
sure
> 
>> +            report_skip("Test requires at least %d vcpus", nb_cpus);
>> +            return true;
>> +    }
>> +
>> +    stats_reset();
>> +
>> +    setup_irq(lpi_handler);
>> +
>> +    for_each_present_cpu(cpu) {
>> +            if (cpu == 0)
>> +                    continue;
>> +            smp_boot_secondary(cpu, secondary_lpi_test);
>> +    }
>> +    wait_on_ready();
>> +
>> +    its_enable_defaults();
>> +
>> +    lpi_stats_expect(-1, -1);
>> +    check_lpi_stats();
>> +
>> +    return false;
> 
> Reverse logic. I'd expect 'return true' for success.
I am going to return an int. In case of error a std negative error will
be returned.
> 
>> +}
>> +
>> +static void test_its_trigger(void)
>> +{
>> +    struct its_collection *col3, *col2;
>> +    struct its_device *dev2, *dev7;
>> +
>> +    if (its_prerequisites(4))
> 
> if (!its_prerequisites(...))
> 
>> +            return;
>> +
>> +    dev2 = its_create_device(2 /* dev id */, 8 /* nb_ites */);
>> +    dev7 = its_create_device(7 /* dev id */, 8 /* nb_ites */);
>> +
>> +    col3 = its_create_collection(3 /* col id */, 3/* target PE */);
>> +    col2 = its_create_collection(2 /* col id */, 2/* target PE */);
>> +
>> +    gicv3_lpi_set_config(8195, LPI_PROP_DEFAULT);
>> +    gicv3_lpi_set_config(8196, LPI_PROP_DEFAULT);
>> +
>> +    its_send_invall(col2);
>> +    its_send_invall(col3);
>> +
>> +    report_prefix_push("int");
>> +    /*
>> +     * dev=2, eventid=20  -> lpi= 8195, col=3
>> +     * dev=7, eventid=255 -> lpi= 8196, col=2
>> +     * Trigger dev2, eventid=20 and dev7, eventid=255
>> +     * Check both LPIs hit
>> +     */
>> +
>> +    its_send_mapd(dev2, true);
>> +    its_send_mapd(dev7, true);
>> +
>> +    its_send_mapc(col3, true);
>> +    its_send_mapc(col2, true);
>> +
>> +    its_send_mapti(dev2, 8195 /* lpi id */,
>> +                   20 /* event id */, col3);
>> +    its_send_mapti(dev7, 8196 /* lpi id */,
>> +                   255 /* event id */, col2);
> 
> No need for line breaks, with the embedded comments it's hard to read
OK
> 
>> +
>> +    lpi_stats_expect(3, 8195);
>> +    its_send_int(dev2, 20);
>> +    check_lpi_stats();
>> +
>> +    lpi_stats_expect(2, 8196);
>> +    its_send_int(dev7, 255);
>> +    check_lpi_stats();
>> +
>> +    report_prefix_pop();
> 
> I think a table of parameters and loop would be nicer than all the
> repeated function calls.
Frankly speaking I am not sure this would really help. We are just
enabling 2 translation paths. I think I prefer to manipulate the low
level objects and helpers rather than playing with a loop and potential
new structs of params.
> 
>> +
>> +    report_prefix_push("inv/invall");
>> +
>> +    /*
>> +     * disable 8195, check dev2/eventid=20 does not trigger the
>> +     * corresponding LPI
>> +     */
>> +    gicv3_lpi_set_config(8195, LPI_PROP_DEFAULT & ~0x1);
> 
> LPI_PROP_DEFAULT & ~LPI_PROP_ENABLED
ok
> 
>> +    its_send_inv(dev2, 20);
>> +
>> +    lpi_stats_expect(-1, -1);
>> +    its_send_int(dev2, 20);
>> +    check_lpi_stats();
>> +
>> +    /*
>> +     * re-enable the LPI but willingly do not call invall
>> +     * so the change in config is not taken into account.
>> +     * The LPI should not hit
>> +     */
>> +    gicv3_lpi_set_config(8195, LPI_PROP_DEFAULT);
>> +    lpi_stats_expect(-1, -1);
>> +    its_send_int(dev2, 20);
>> +    check_lpi_stats();
>> +
>> +    /* Now call the invall and check the LPI hits */
>> +    its_send_invall(col3);
>> +    lpi_stats_expect(3, 8195);
>> +    its_send_int(dev2, 20);
>> +    check_lpi_stats();
>> +
>> +    report_prefix_pop();
> 
> Need blank line here.
OK
> 
>> +    /*
>> +     * Unmap device 2 and check the eventid 20 formerly
>> +     * attached to it does not hit anymore
>> +     */
>> +    report_prefix_push("mapd valid=false");
> 
> Above you have the prefix-push before the comment explaining the test.
> After is probably better, but whatever, as long as it's consistent.
moved after
> 
>> +    its_send_mapd(dev2, false);
>> +    lpi_stats_expect(-1, -1);
>> +    its_send_int(dev2, 20);
>> +    check_lpi_stats();
>> +    report_prefix_pop();
>> +
>> +    /* Unmap the collection this time and check no LPI does hit */
>> +    report_prefix_push("mapc valid=false");
>> +    its_send_mapc(col2, false);
>> +    lpi_stats_expect(-1, -1);
>> +    its_send_int(dev7, 255);
>> +    check_lpi_stats();
>> +    report_prefix_pop();
>> +}
>>  #endif
>>  
>>  int main(int argc, char **argv)
>> @@ -594,6 +796,10 @@ int main(int argc, char **argv)
>>              report_prefix_push(argv[1]);
>>              gic_test_mmio();
>>              report_prefix_pop();
>> +    } else if (!strcmp(argv[1], "its-trigger")) {
>> +            report_prefix_push(argv[1]);
>> +            test_its_trigger();
>> +            report_prefix_pop();
>>      } else if (strcmp(argv[1], "its-introspection") == 0) {
>>              report_prefix_push(argv[1]);
>>              test_its_introspection();
>> diff --git a/arm/unittests.cfg b/arm/unittests.cfg
>> index ba2b31b..bfafec5 100644
>> --- a/arm/unittests.cfg
>> +++ b/arm/unittests.cfg
>> @@ -129,6 +129,13 @@ extra_params = -machine gic-version=3 -append 
>> 'its-introspection'
>>  groups = its
>>  arch = arm64
>>  
>> +[its-trigger]
>> +file = gic.flat
>> +smp = $MAX_SMP
>> +extra_params = -machine gic-version=3 -append 'its-trigger'
>> +groups = its
>> +arch = arm64
>> +
>>  # Test PSCI emulation
>>  [psci]
>>  file = psci.flat
>> -- 
>> 2.20.1
>>
> 
> Thanks,
> drew 
> 
Thanks

Eric