Re: [PATCH net-next v5 2/3] connector/cn_proc: Kunit tests for threads hash table

[Anjali Kulkarni <anjali.k.kulkarni@oracle.com>]

> On Oct 17, 2024, at 5:55 PM, Stanislav Fomichev <stfomichev@gmail.com> wrote:
> 
> On 10/18, Anjali Kulkarni wrote:
>> 
>> 
>>> On Oct 17, 2024, at 5:13 PM, Stanislav Fomichev <stfomichev@gmail.com> wrote:
>>> 
>>> On 10/17, Anjali Kulkarni wrote:
>>>> Kunit tests to test hash table add, delete, duplicate add and delete.
>>>> Add following configs and compile kernel code:
>>>> 
>>>> CONFIG_CONNECTOR=y
>>>> CONFIG_PROC_EVENTS=y
>>>> CONFIG_NET=y
>>>> CONFIG_KUNIT=m
>>>> CONFIG_CN_HASH_KUNIT_TEST=m
>>>> 
>>>> To run kunit tests:
>>>> sudo modprobe cn_hash_test
>>>> 
>>>> Output of kunit tests and hash table contents are displayed in
>>>> /var/log/messages (at KERN_DEBUG level).
>>>> 
>>>> Signed-off-by: Anjali Kulkarni <anjali.k.kulkarni@oracle.com>
>>>> ---
>>>> drivers/connector/cn_hash.c   |  40 ++++++++
>>>> drivers/connector/connector.c |  12 +++
>>>> include/linux/connector.h     |   4 +
>>>> lib/Kconfig.debug             |  17 ++++
>>>> lib/Makefile                  |   1 +
>>>> lib/cn_hash_test.c            | 167 ++++++++++++++++++++++++++++++++++
>>>> lib/cn_hash_test.h            |  10 ++
>>>> 7 files changed, 251 insertions(+)
>>>> create mode 100644 lib/cn_hash_test.c
>>>> create mode 100644 lib/cn_hash_test.h
>>>> 
>>>> diff --git a/drivers/connector/cn_hash.c b/drivers/connector/cn_hash.c
>>>> index a079e9bcea6d..40099b5908ac 100644
>>>> --- a/drivers/connector/cn_hash.c
>>>> +++ b/drivers/connector/cn_hash.c
>>>> @@ -170,6 +170,46 @@ int cn_hash_get_exval(struct cn_hash_dev *hdev, pid_t pid)
>>>> return -EINVAL;
>>>> }
>>>> 
>>>> +int cn_hash_display_hlist(struct cn_hash_dev *hdev, pid_t pid, int max_len,
>>>> + int *hkey, int *key_display)
>>>> +{
>>>> + struct uexit_pid_hnode *hnode;
>>>> + int key, count = 0;
>>>> +
>>>> + mutex_lock(&hdev->uexit_hash_lock);
>>>> + key = hash_min(pid, HASH_BITS(hdev->uexit_pid_htable));
>>>> + pr_debug("Bucket: %d\n", key);
>>>> +
>>>> + hlist_for_each_entry(hnode,
>>>> + &hdev->uexit_pid_htable[key],
>>>> + uexit_pid_hlist) {
>>>> + if (key_display[key] != 1) {
>>>> + if (hnode->uexit_pid_hlist.next == NULL)
>>>> + pr_debug("pid %d ", hnode->pid);
>>>> + else
>>>> + pr_debug("pid %d --> ", hnode->pid);
>>>> + }
>>>> + count++;
>>>> + }
>>>> +
>>>> + mutex_unlock(&hdev->uexit_hash_lock);
>>>> +
>>>> + if ((key_display[key] != 1) && !count)
>>>> + pr_debug("(empty)\n");
>>>> +
>>>> + pr_debug("\n");
>>>> +
>>>> + *hkey = key;
>>>> +
>>>> + if (count > max_len) {
>>>> + pr_err("%d entries in hlist for key %d, expected %d\n",
>>>> + count, key, max_len);
>>>> + return -EINVAL;
>>>> + }
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> bool cn_hash_table_empty(struct cn_hash_dev *hdev)
>>>> {
>>>> bool is_empty;
>>>> diff --git a/drivers/connector/connector.c b/drivers/connector/connector.c
>>>> index c1c0dcec53c0..2be2fe1adc12 100644
>>>> --- a/drivers/connector/connector.c
>>>> +++ b/drivers/connector/connector.c
>>>> @@ -304,6 +304,18 @@ int cn_get_exval(pid_t pid)
>>>> }
>>>> EXPORT_SYMBOL_GPL(cn_get_exval);
>>>> 
>>>> +int cn_display_hlist(pid_t pid, int max_len, int *hkey, int *key_display)
>>>> +{
>>>> + struct cn_dev *dev = &cdev;
>>>> +
>>>> + if (!cn_already_initialized)
>>>> + return 0;
>>>> +
>>>> + return cn_hash_display_hlist(dev->hdev, pid, max_len,
>>>> + hkey, key_display);
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(cn_display_hlist);
>>>> +
>>>> bool cn_table_empty(void)
>>>> {
>>>> struct cn_dev *dev = &cdev;
>>>> diff --git a/include/linux/connector.h b/include/linux/connector.h
>>>> index 5384e4bb98e8..a75c3fcf182a 100644
>>>> --- a/include/linux/connector.h
>>>> +++ b/include/linux/connector.h
>>>> @@ -168,4 +168,8 @@ int cn_get_exval(pid_t pid);
>>>> bool cn_table_empty(void);
>>>> bool cn_hash_table_empty(struct cn_hash_dev *hdev);
>>>> 
>>>> +int cn_display_hlist(pid_t pid, int max_len, int *hkey, int *key_display);
>>>> +int cn_hash_display_hlist(struct cn_hash_dev *hdev, pid_t pid, int max_len,
>>>> + int *hkey, int *key_display);
>>>> +
>>>> #endif /* __CONNECTOR_H */
>>>> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
>>>> index 7315f643817a..290cf0a6befa 100644
>>>> --- a/lib/Kconfig.debug
>>>> +++ b/lib/Kconfig.debug
>>>> @@ -2705,6 +2705,23 @@ config HASHTABLE_KUNIT_TEST
>>>> 
>>>> If unsure, say N.
>>>> 
>>>> +config CN_HASH_KUNIT_TEST
>>>> + tristate "KUnit Test for connector hashtable code" if !KUNIT_ALL_TESTS
>>>> + depends on KUNIT
>>>> + default KUNIT_ALL_TESTS
>>>> + help
>>>> +  This builds the hashtable KUnit test suite.
>>>> +  It tests the basic functionality of the API defined in
>>>> +  drivers/connector/cn_hash.c.
>>>> +  CONFIG_CONNECTOR=y, CONFIG_PROC_EVENTS=y and CONFIG_NET=y needs
>>>> +  to be enabled along with CONFIG_CN_HASH_KUNIT_TEST=m and
>>>> +  CONFIG_KUNIT=m in .config file to compile and then test as a kernel
>>>> +  module with "modprobe cn_hash_test".
>>>> +  For more information on KUnit and unit tests in general please
>>>> +  refer to the KUnit documentation in Documentation/dev-tools/kunit/.
>>>> +
>>>> +  If unsure, say N.
>>>> +
>>> 
>>> Looks like this needs to depend on CONFIG_CONNECTOR? Otherwise, the
>>> existing kunit tester complains about the missing symbols (see below).
>>> Please also hold off reposting for a couple of days to give people some
>>> time to review.
>>> 
>>> ERROR:root:ld: vmlinux.o: in function `cn_hash_test_dup_del':
>>> cn_hash_test.c:(.text+0x3e9dc3): undefined reference to `cn_del_get_exval'
>>> ld: cn_hash_test.c:(.text+0x3e9dee): undefined reference to `cn_del_get_exval'
>>> ld: cn_hash_test.c:(.text+0x3e9e22): undefined reference to `cn_table_empty'
>>> ld: vmlinux.o: in function `cn_display_htable':
>>> cn_hash_test.c:(.text+0x3e9f67): undefined reference to `cn_display_hlist'
>>> ld: vmlinux.o: in function `cn_hash_test_del_get_exval':
>>> cn_hash_test.c:(.text+0x3ea037): undefined reference to `cn_del_get_exval'
>>> ld: cn_hash_test.c:(.text+0x3ea088): undefined reference to `cn_table_empty'
>>> ld: vmlinux.o: in function `cn_hash_test_dup_add':
>>> cn_hash_test.c:(.text+0x3ea176): undefined reference to `cn_add_elem'
>>> ld: cn_hash_test.c:(.text+0x3ea19e): undefined reference to `cn_get_exval'
>>> ld: cn_hash_test.c:(.text+0x3ea1dc): undefined reference to `cn_add_elem'
>>> ld: cn_hash_test.c:(.text+0x3ea205): undefined reference to `cn_get_exval'
>>> ld: vmlinux.o: in function `cn_hash_test_del':
>>> cn_hash_test.c:(.text+0x3ea387): undefined reference to `cn_del_get_exval'
>>> ld: cn_hash_test.c:(.text+0x3ea3ab): undefined reference to `cn_get_exval'
>>> ld: cn_hash_test.c:(.text+0x3ea3fd): undefined reference to `cn_table_empty'
>>> ld: vmlinux.o: in function `cn_hash_test_add':
>>> cn_hash_test.c:(.text+0x3ea571): undefined reference to `cn_add_elem'
>>> ld: cn_hash_test.c:(.text+0x3ea591): undefined reference to `cn_get_exval'
>>> make[3]: *** [../scripts/Makefile.vmlinux:34: vmlinux] Error 1
>>> make[2]: *** [/home/kunit/testing/Makefile:1166: vmlinux] Error 2
>>> make[1]: *** [/home/kunit/testing/Makefile:224: __sub-make] Error 2
>>> make: *** [Makefile:224: __sub-make] Error 2
>> 
>> Yes, I have added in the comments for CN_HASH_KUNIT_TEST, it depends on:
>> CONFIG_CONNECTOR, CONFIG_PROC_EVENTS, CONFIG_NET. I didn’t realize
>> I could add these to the “depends” field.
>> So something like this: (let me know if you see any issues)
>> 
>>        tristate "KUnit Test for connector hashtable code" if !KUNIT_ALL_TESTS
>>        depends on KUNIT
>> +       depends on CONNECTOR && PROC_EVENTS
>> +       depends on NET
>>        default KUNIT_ALL_TESTS
>> 
>> These are the configs I add to my .config file and compile it as a module and then
>> do modprobe to test.
> 
> [..]
> 
>> Are you running the kunit tester with kunit.py?
> 
> Yes, make sure all required options are picked up by
> "./tools/testing/kunit/kunit.py run" instead of manually adding options
> and doing modprobe.

I’m unable to run kunit.py, it runs into various issues like UML, permissions, other 
errors. I talked to the kunit guys about this and we have been debugging it for a
while but unable to fix the environment issue. But the tests work fine.

What kind of VM is this being run on? Like ubuntu etc.? I will try on a different
OS and check if kunit.py works. 

Anjali