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

From: Stanislav Fomichev <[email-masked]>
Date: Tue, 22 Oct 2024 16:50:02 -0700

On 10/22, Anjali Kulkarni wrote:
> 
> 
> > On Oct 17, 2024, at 5:55 PM, Stanislav Fomichev <[email-masked]> wrote:
> > 
> > On 10/18, Anjali Kulkarni wrote:
> >> 
> >> 
> >>> On Oct 17, 2024, at 5:13 PM, Stanislav Fomichev <[email-masked]> 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 <[email-masked]>
> >>>> ---
> >>>> 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.
> 
> The environment issues are resolved and I am able to run kunit.py, but my tests
> are not invoked without giving options via —kconfig-add. Other tests are also not
> invoked. Running with the manual options runs 413 tests, and with just kunit.py
> runs 389 tests. (I have added 6). Any idea how I can make it run my tests?

The runner does: ./tools/testing/kunit/kunit.py run --alltests
Is it not enough in your case? What options do you pass via
--kconfig-add? Is it because CONNECTOR stuff is disabled by default?