Hi Alexandru,
On 12/10/20 3:45 PM, Alexandru Elisei wrote:
> Hi Eric,
>
> On 12/3/20 1:39 PM, Auger Eric wrote:
>>
>> On 11/25/20 4:51 PM, Alexandru Elisei wrote:
>>> check_acked() has several peculiarities: is the only function among the
>>> check_* functions which calls report() directly, it does two things
>>> (waits for interrupts and checks for misfired interrupts) and it also
>>> mixes printf, report_info and report calls.
>>>
>>> check_acked() also reports a pass and returns as soon all the target CPUs
>>> have received interrupts, However, a CPU not having received an interrupt
>>> *now* does not guarantee not receiving an eroneous interrupt if we wait
>> erroneous
>>> long enough.
>>>
>>> Rework the function by splitting it into two separate functions, each with
>>> a single responsability: wait_for_interrupts(), which waits for the
>>> expected interrupts to fire, and check_acked() which checks that interrupts
>>> have been received as expected.
>>>
>>> wait_for_interrupts() also waits an extra 100 milliseconds after the
>>> expected interrupts have been received in an effort to make sure we don't
>>> miss misfiring interrupts.
>>>
>>> Splitting check_acked() into two functions will also allow us to
>>> customize the behavior of each function in the future more easily
>>> without using an unnecessarily long list of arguments for check_acked().
>>>
>>> CC: Andre Przywara <andre.przywara@xxxxxxx>
>>> Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
>>> ---
>>> arm/gic.c | 73 +++++++++++++++++++++++++++++++++++--------------------
>>> 1 file changed, 47 insertions(+), 26 deletions(-)
>>>
>>> diff --git a/arm/gic.c b/arm/gic.c
>>> index 544c283f5f47..dcdab7d5f39a 100644
>>> --- a/arm/gic.c
>>> +++ b/arm/gic.c
>>> @@ -62,41 +62,42 @@ static void stats_reset(void)
>>> }
>>> }
>>>
>>> -static void check_acked(const char *testname, cpumask_t *mask)
>>> +static void wait_for_interrupts(cpumask_t *mask)
>>> {
>>> - int missing = 0, extra = 0, unexpected = 0;
>>> int nr_pass, cpu, i;
>>> - bool bad = false;
>>>
>>> /* Wait up to 5s for all interrupts to be delivered */
>>> - for (i = 0; i < 50; ++i) {
>>> + for (i = 0; i < 50; i++) {
>>> mdelay(100);
>>> nr_pass = 0;
>>> for_each_present_cpu(cpu) {
>>> + /*
>>> + * A CPU having receied more than one interrupts will
>> received
>>> + * show up in check_acked(), and no matter how long we
>>> + * wait it cannot un-receive it. Consier at least one
>> consider
>
> Will fix all three typos, thanks.
>
>>> + * interrupt as a pass.
>>> + */
>>> nr_pass += cpumask_test_cpu(cpu, mask) ?
>>> - acked[cpu] == 1 : acked[cpu] == 0;
>>> - smp_rmb(); /* pairs with smp_wmb in ipi_handler */
>>> -
>>> - if (bad_sender[cpu] != -1) {
>>> - printf("cpu%d received IPI from wrong sender %d\n",
>>> - cpu, bad_sender[cpu]);
>>> - bad = true;
>>> - }
>>> -
>>> - if (bad_irq[cpu] != -1) {
>>> - printf("cpu%d received wrong irq %d\n",
>>> - cpu, bad_irq[cpu]);
>>> - bad = true;
>>> - }
>>> + acked[cpu] >= 1 : acked[cpu] == 0;
>>> }
>>> +
>>> if (nr_pass == nr_cpus) {
>>> - report(!bad, "%s", testname);
>>> if (i)
>>> - report_info("took more than %d ms", i * 100);
>>> + report_info("interrupts took more than %d ms", i * 100);
>>> + mdelay(100);
>>> return;
>>> }
>>> }
>>>
>>> + report_info("interrupts timed-out (5s)");
>>> +}
>>> +
>>> +static bool check_acked(cpumask_t *mask)
>>> +{
>>> + int missing = 0, extra = 0, unexpected = 0;
>>> + bool pass = true;
>>> + int cpu;
>>> +
>>> for_each_present_cpu(cpu) {
>>> if (cpumask_test_cpu(cpu, mask)) {
>>> if (!acked[cpu])
>>> @@ -107,11 +108,28 @@ static void check_acked(const char *testname, cpumask_t *mask)
>>> if (acked[cpu])
>>> ++unexpected;
>>> }
>>> + smp_rmb(); /* pairs with smp_wmb in ipi_handler */
>>> +
>>> + if (bad_sender[cpu] != -1) {
>>> + report_info("cpu%d received IPI from wrong sender %d",
>>> + cpu, bad_sender[cpu]);
>>> + pass = false;
>>> + }
>>> +
>>> + if (bad_irq[cpu] != -1) {
>>> + report_info("cpu%d received wrong irq %d",
>>> + cpu, bad_irq[cpu]);
>>> + pass = false;
>>> + }
>>> + }
>>> +
>>> + if (missing || extra || unexpected) {
>>> + report_info("ACKS: missing=%d extra=%d unexpected=%d",
>>> + missing, extra, unexpected);
>>> + pass = false;
>>> }
>>>
>>> - report(false, "%s", testname);
>>> - report_info("Timed-out (5s). ACKS: missing=%d extra=%d unexpected=%d",
>>> - missing, extra, unexpected);
>>> + return pass;
>>> }
>>>
>>> static void check_spurious(void)
>>> @@ -300,7 +318,8 @@ static void ipi_test_self(void)
>>> cpumask_clear(&mask);
>>> cpumask_set_cpu(smp_processor_id(), &mask);
>>> gic->ipi.send_self();
>>> - check_acked("IPI: self", &mask);
>>> + wait_for_interrupts(&mask);
>>> + report(check_acked(&mask), "Interrupts received");
>>> report_prefix_pop();
>>> }
>>>
>>> @@ -315,7 +334,8 @@ static void ipi_test_smp(void)
>>> for (i = smp_processor_id() & 1; i < nr_cpus; i += 2)
>>> cpumask_clear_cpu(i, &mask);
>>> gic_ipi_send_mask(IPI_IRQ, &mask);
>>> - check_acked("IPI: directed", &mask);
>>> + wait_for_interrupts(&mask);
>>> + report(check_acked(&mask), "Interrupts received");
>> both ipi_test_smp and ipi_test_self are called from the same test so
>> better to use different error messages like it was done originally.
>
> I used the same error message because the tests have a different prefix
> ("target-list" versus "broadcast"). Do you think there are cases where that's not
> enough?
I think in "ipi" test,
ipi_test -> ipi_send -> ipi_test_self, ipi_test_smp
Thanks
Eric
>
> Thanks,
> Alex
>
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