Re: [kvm-unit-tests PATCH v5 13/13] arm/arm64: ITS: pending table migration test

[Auger Eric <eric.auger@redhat.com>]

On 3/11/20 1:07 PM, Zenghui Yu wrote:
> Hi Eric,
> 
> On 2020/3/10 22:54, Eric Auger wrote:
>> Add two new migration tests. One testing the migration of
>> a topology where collection were unmapped. The second test
>> checks the migration of the pending table.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>>
>> ---
>>
>> v4 -> v5:
>> - move stub from header to arm/gic.c
>>
>> v3 -> v4:
>> - do not talk about odd/even CPUs, use pe0 and pe1
>> - comment the delay
>>
>> v2 -> v3:
>> - tests belong to both its and migration groups
>> - use LPI(i)
>> - gicv3_lpi_set_pending_table_bit renamed into gicv3_lpi_set_clr_pending
>> ---
>>   arm/gic.c         | 146 ++++++++++++++++++++++++++++++++++++++++++++++
>>   arm/unittests.cfg |  16 +++++
>>   2 files changed, 162 insertions(+)
>>
>> diff --git a/arm/gic.c b/arm/gic.c
>> index b8fbc13..e6ffbc3 100644
>> --- a/arm/gic.c
>> +++ b/arm/gic.c
>> @@ -193,6 +193,7 @@ static void lpi_handler(struct pt_regs *regs
>> __unused)
>>       smp_rmb(); /* pairs with wmb in lpi_stats_expect */
>>       lpi_stats.observed.cpu_id = smp_processor_id();
>>       lpi_stats.observed.lpi_id = irqnr;
>> +    acked[lpi_stats.observed.cpu_id]++;
>>       smp_wmb(); /* pairs with rmb in check_lpi_stats */
>>   }
>>   @@ -236,6 +237,22 @@ static void secondary_lpi_test(void)
>>       while (1)
>>           wfi();
>>   }
>> +
>> +static void check_lpi_hits(int *expected, const char *msg)
>> +{
>> +    bool pass = true;
>> +    int i;
>> +
>> +    for (i = 0; i < nr_cpus; i++) {
>> +        if (acked[i] != expected[i]) {
>> +            report_info("expected %d LPIs on PE #%d, %d observed",
>> +                    expected[i], i, acked[i]);
>> +            pass = false;
>> +            break;
>> +        }
>> +    }
>> +    report(pass, "%s", msg);
>> +}
>>   #endif
>>     static void gicv2_ipi_send_self(void)
>> @@ -591,6 +608,8 @@ static void gic_test_mmio(void)
>>   static void test_its_introspection(void) {}
>>   static void test_its_trigger(void) {}
>>   static void test_its_migration(void) {}
>> +static void test_its_pending_migration(void) {}
>> +static void test_migrate_unmapped_collection(void) {}
>>     #else /* __aarch64__ */
>>   @@ -659,6 +678,17 @@ static int its_prerequisites(int nb_cpus)
>>       return 0;
>>   }
>>   +static void set_lpi(struct its_device *dev, u32 eventid, u32 physid,
>> +            struct its_collection *col)
>> +{
>> +    assert(dev && col);
>> +
>> +    its_send_mapti(dev, physid, eventid, col);
>> +
>> +    gicv3_lpi_set_config(physid, LPI_PROP_DEFAULT);
>> +    its_send_invall(col);
> 
> Again, the col hasn't been mapped currently.
right. Moving it outside of the helper then
> 
>> +}
>> +
>>   /*
>>    * Setup the configuration for those mappings:
>>    * dev_id=2 event=20 -> vcpu 3, intid=8195
>> @@ -799,6 +829,114 @@ static void test_its_migration(void)
>>       its_send_int(dev7, 255);
>>       check_lpi_stats("dev7/eventid=255 triggers LPI 8196 on PE #2
>> after migration");
>>   }
>> +
>> +static void test_migrate_unmapped_collection(void)
>> +{
>> +    struct its_collection *col;
>> +    struct its_device *dev2, *dev7;
>> +    int pe0 = nr_cpus - 1;
>> +    u8 config;
>> +
>> +    if (its_setup1())
>> +        return;
>> +
>> +    col = its_create_collection(pe0, pe0);
>> +    dev2 = its_get_device(2);
>> +    dev7 = its_get_device(7);
>> +
>> +    /* MAPTI with the collection unmapped */
>> +    set_lpi(dev2, 0, 8192, col);
>> +
>> +    puts("Now migrate the VM, then press a key to continue...\n");
>> +    (void)getchar();
>> +    report_info("Migration complete");
>> +
>> +    /* on the destination, map the collection */
>> +    its_send_mapc(col, true);
>> +
>> +    lpi_stats_expect(2, 8196);
>> +    its_send_int(dev7, 255);
>> +    check_lpi_stats("dev7/eventid= 255 triggered LPI 8196 on PE #2");
>> +
>> +    config = gicv3_lpi_get_config(8192);
>> +    report(config == LPI_PROP_DEFAULT,
>> +           "Config of LPI 8192 was properly migrated");
>> +
>> +    lpi_stats_expect(pe0, 8192);
>> +    its_send_int(dev2, 0);
>> +    check_lpi_stats("dev2/eventid = 0 triggered LPI 8192 on PE0");
>> +
>> +    /* unmap the collection */
>> +    its_send_mapc(col, false);
> 
> Again, behavior is unpredictable.
yep removing that test.
> 
>> +
>> +    lpi_stats_expect(-1, -1);
>> +    its_send_int(dev2, 0);
>> +    check_lpi_stats("no LPI triggered after collection unmapping");
>> +}
>> +
>> +static void test_its_pending_migration(void)
>> +{
>> +    struct its_device *dev;
>> +    struct its_collection *collection[2];
>> +    int *expected = malloc(nr_cpus * sizeof(int));
>> +    int pe0 = nr_cpus - 1, pe1 = nr_cpus - 2;
>> +    u64 pendbaser;
>> +    void *ptr;
>> +    int i;
>> +
>> +    if (its_prerequisites(4))
>> +        return;
>> +
>> +    dev = its_create_device(2 /* dev id */, 8 /* nb_ites */);
>> +    its_send_mapd(dev, true);
>> +
>> +    collection[0] = its_create_collection(pe0, pe0);
>> +    collection[1] = its_create_collection(pe1, pe1);
>> +    its_send_mapc(collection[0], true);
>> +    its_send_mapc(collection[1], true);
>> +
>> +    /* disable lpi at redist level */
>> +    gicv3_lpi_rdist_disable(pe0);
>> +    gicv3_lpi_rdist_disable(pe1);
>> +
>> +    /* lpis are interleaved inbetween the 2 PEs */
>> +    for (i = 0; i < 256; i++) {
>> +        struct its_collection *col = i % 2 ? collection[0] :
>> +                             collection[1];
>> +        int vcpu = col->target_address >> 16;
>> +
>> +        its_send_mapti(dev, LPI(i), i, col);
>> +        gicv3_lpi_set_config(LPI(i), LPI_PROP_DEFAULT);
>> +        gicv3_lpi_set_clr_pending(vcpu, LPI(i), true);
>> +    }
>> +    its_send_invall(collection[0]);
>> +    its_send_invall(collection[1]);
>> +
>> +    /* Set the PTZ bit on each pendbaser */
> 
> 'Clear' the PTZ.
yep
> 
> Otherwise looks good!

Thank you for your careful review!

Best Regards

Eric
> 
>> +
>> +    expected[pe0] = 128;
>> +    expected[pe1] = 128;
>> +
>> +    ptr = gicv3_data.redist_base[pe0] + GICR_PENDBASER;
>> +    pendbaser = readq(ptr);
>> +    writeq(pendbaser & ~GICR_PENDBASER_PTZ, ptr);
>> +
>> +    ptr = gicv3_data.redist_base[pe1] + GICR_PENDBASER;
>> +    pendbaser = readq(ptr);
>> +    writeq(pendbaser & ~GICR_PENDBASER_PTZ, ptr);
>> +
>> +    gicv3_lpi_rdist_enable(pe0);
>> +    gicv3_lpi_rdist_enable(pe1);
>> +
>> +    puts("Now migrate the VM, then press a key to continue...\n");
>> +    (void)getchar();
>> +    report_info("Migration complete");
>> +
>> +    /* let's wait for the 256 LPIs to be handled */
>> +    mdelay(1000);
>> +
>> +    check_lpi_hits(expected, "128 LPIs on both PE0 and PE1 after
>> migration");
>> +}
> 
> Thanks,
> Zenghui
>