2015-02-04 16:14:42

by Rob Herring

[permalink] [raw]
Subject: Re: [PATCH RFC 0/2] of/unittest: Add reference count tests

On Fri, Jan 23, 2015 at 10:10 AM, Geert Uytterhoeven
<[email protected]> wrote:
> Hi Grant, Rob,
>
> This patch series adds tests to detect reference count imbalances.
> The tests use a fixed list of paths to devices nodes (required device
> nodes in a minimal DTS, and device nodes present in unittest-data).
> I considered scanning for all present device node instead, but these
> are more likely to change while running the test.
>
> These tests are executed only if CONFIG_OF_DYNAMIC=y.
>
> Patches are against devicetree/next, with "[PATCH] of: Add missing
> of_node_put() in of_find_node_by_path()" (or the alternative proposed
> by Grant) applied.
>
> Note that it shows 44 failures, which I haven't investigated yet:

Do you plan to?

While this could find problems in the unittests or the core OF code,
the vast majority of the problems are likely in the users and this
doesn't help with those. This whole issue of ref counts has been
discussed some and probably needs to be redesigned or instrumented in
a way that users can validate. But then it is pretty low priority
given that ref counts only matter on pseries.

Rob

>
> ### dt-test ### start of selftest - you will see error messages
> ### dt-test ### FAIL of_selftest_refcnt():1512 /testcase-data/duplicate-name#1: not found
> ### dt-test ### FAIL of_selftest_refcnt():1512 /testcase-data/duplicate-name#1: not found
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data: expected:23 got:25
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/interrupts/intc0: expected:2 got:19
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/interrupts/intc1: expected:2 got:9
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/interrupts/intc2: expected:2 got:8
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/interrupts/intmap0: expected:4 got:7
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/interrupts/intmap1: expected:4 got:5
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/platform-tests: expected:4 got:5
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/phandle-tests/consumer-a: expected:4 got:6
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/phandle-tests/provider0: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/phandle-tests/provider1: expected:2 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/phandle-tests/provider2: expected:2 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/phandle-tests/provider3: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/a/name2: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/b/name2: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/c/name2: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name0: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name1: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name3: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name4: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name5: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name6: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name7: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name8: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/match-node/name9: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay-node/test-bus: expected:12 got:16
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay-node/test-bus/test-selftest100: expected:2 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay-node/test-bus/test-selftest0: expected:2 got:6
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay-node/test-bus/test-selftest1: expected:2 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay-node/test-bus/test-selftest2: expected:2 got:6
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay-node/test-bus/test-selftest3: expected:2 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay0/fragment@0/__overlay__: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay1/fragment@0/__overlay__: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay2/fragment@0/__overlay__: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay3/fragment@0/__overlay__: expected:2 got:3
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay4/fragment@0/__overlay__: expected:3 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay6: expected:3 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay7: expected:3 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay8: expected:3 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/overlay9: expected:3 got:4
> ### dt-test ### FAIL of_selftest_refcnt():1512 /testcase-data/duplicate-name#1: not found
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/testcase-device1: expected:4 got:6
> ### dt-test ### FAIL of_selftest_refcnt():1522 /testcase-data/testcase-device2: expected:4 got:6
> ### dt-test ### end of selftest - 619 passed, 44 failed
>
> Geert Uytterhoeven (2):
> of: Allow selection of OF_DYNAMIC and OF_OVERLAY if OF_UNITTEST
> of/unittest: Add reference count tests
>
> drivers/of/Kconfig | 13 ++++-
> drivers/of/unittest.c | 155 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 166 insertions(+), 2 deletions(-)
>
> --
> 1.9.1
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds


2015-02-04 17:08:41

by Geert Uytterhoeven

[permalink] [raw]
Subject: Re: [PATCH RFC 0/2] of/unittest: Add reference count tests

Hi Rob,

On Wed, Feb 4, 2015 at 5:14 PM, Rob Herring <[email protected]> wrote:
> On Fri, Jan 23, 2015 at 10:10 AM, Geert Uytterhoeven
> <[email protected]> wrote:
>> This patch series adds tests to detect reference count imbalances.
>> The tests use a fixed list of paths to devices nodes (required device
>> nodes in a minimal DTS, and device nodes present in unittest-data).
>> I considered scanning for all present device node instead, but these
>> are more likely to change while running the test.
>>
>> These tests are executed only if CONFIG_OF_DYNAMIC=y.
>>
>> Patches are against devicetree/next, with "[PATCH] of: Add missing
>> of_node_put() in of_find_node_by_path()" (or the alternative proposed
>> by Grant) applied.
>>
>> Note that it shows 44 failures, which I haven't investigated yet:
>
> Do you plan to?

Maybe. It doesn't have such a high priority in my task list...

> While this could find problems in the unittests or the core OF code,
> the vast majority of the problems are likely in the users and this
> doesn't help with those. This whole issue of ref counts has been
> discussed some and probably needs to be redesigned or instrumented in
> a way that users can validate. But then it is pretty low priority
> given that ref counts only matter on pseries.

I agree most issues are in the users.
However, I did find one issue in the core code.

Note that the reference counts may become more important in the future,
as OF_OVERLAY selects OF_DYNAMIC.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds