Re: [PATCH] selftest: rtc: Add to check rtc alarm status for alarm related test

From: Joseph Jang
Date: Fri May 17 2024 - 03:54:24 EST




On 2024/5/17 3:19 PM, Alexandre Belloni wrote:
On 16/05/2024 19:28:47-0700, Joseph Jang wrote:
In alarm_wkalm_set and alarm_wkalm_set_minute test, they use different
ioctl (RTC_ALM_SET/RTC_WKALM_SET) for alarm feature detection. They will
skip testing if RTC_ALM_SET/RTC_WKALM_SET ioctl returns an EINVAL error
code. This design may miss detecting real problems when the
efi.set_wakeup_time() return errors and then RTC_ALM_SET/RTC_WKALM_SET
ioctl returns an EINVAL error code with RTC_FEATURE_ALARM enabled.

In order to make rtctest more explicit and robust, we propose to use
RTC_PARAM_GET ioctl interface to check rtc alarm feature state before
running alarm related tests. If the kernel does not support RTC_PARAM_GET
ioctl interface, we will fallback to check the presence of "alarm" in
/proc/driver/rtc.

The rtctest requires the read permission on /dev/rtc0. The rtctest will
be skipped if the /dev/rtc0 is not readable.


This change as to be separated. Also, I'm not sure what happened with
https://lore.kernel.org/all/20230717175251.54390-1-atulpant.linux@xxxxxxxxx/


I apply above patch and seems like still cannot detect the read
permission on /dev/rtc0. I guess the 'F_OK' just check the `/dev/rtc0`
was there.

I share the error logs by following for your reference.

TAP version 13
1..1
# timeout set to 210
# selftests: rtc: rtctest
# TAP version 13
# 1..8
# # Starting 8 tests from 1 test cases.
# # RUN rtc.date_read ...
# # rtctest.c:53:date_read:Expected -1 (-1) != self->fd (-1)
# # date_read: Test terminated by assertion
# # FAIL rtc.date_read

Not sure if we could skip the testing by following change ?

FIXTURE_SETUP(rtc) {
+ if (access(rtc_file, R_OK) != 0)
+ SKIP(return, "Skipping test since cannot access %s, perhaps miss sudo",
+ rtc_file)
+
self->fd = open(rtc_file, O_RDONLY);
}

And I make sure we need root permission to access `/dev/rtc0`.



Requires commit 101ca8d05913b ("rtc: efi: Enable SET/GET WAKEUP services
as optional")

Reviewed-by: Jeremy Szu <jszu@xxxxxxxxxx>
Reviewed-by: Matthew R. Ochs <mochs@xxxxxxxxxx>
Signed-off-by: Joseph Jang <jjang@xxxxxxxxxx>
---
tools/testing/selftests/rtc/Makefile | 2 +-
tools/testing/selftests/rtc/rtctest.c | 72 +++++++++++++++++++--------
2 files changed, 53 insertions(+), 21 deletions(-)

diff --git a/tools/testing/selftests/rtc/Makefile b/tools/testing/selftests/rtc/Makefile
index 55198ecc04db..6e3a98fb24ba 100644
--- a/tools/testing/selftests/rtc/Makefile
+++ b/tools/testing/selftests/rtc/Makefile
@@ -1,5 +1,5 @@
# SPDX-License-Identifier: GPL-2.0
-CFLAGS += -O3 -Wl,-no-as-needed -Wall
+CFLAGS += -O3 -Wl,-no-as-needed -Wall -I../../../../usr/include/
LDLIBS += -lrt -lpthread -lm
TEST_GEN_PROGS = rtctest
diff --git a/tools/testing/selftests/rtc/rtctest.c b/tools/testing/selftests/rtc/rtctest.c
index 63ce02d1d5cc..aa47b17fbd1a 100644
--- a/tools/testing/selftests/rtc/rtctest.c
+++ b/tools/testing/selftests/rtc/rtctest.c
@@ -8,6 +8,7 @@
#include <errno.h>
#include <fcntl.h>
#include <linux/rtc.h>
+#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>
@@ -24,12 +25,17 @@
#define READ_LOOP_SLEEP_MS 11
static char *rtc_file = "/dev/rtc0";
+static char *rtc_procfs = "/proc/driver/rtc";
FIXTURE(rtc) {
int fd;
};
FIXTURE_SETUP(rtc) {
+ if (access(rtc_file, R_OK) != 0)
+ SKIP(return, "Skipping test since cannot access %s, perhaps miss sudo",
+ rtc_file);

+
self->fd = open(rtc_file, O_RDONLY);
}
@@ -82,6 +88,36 @@ static void nanosleep_with_retries(long ns)
}
}
+static bool is_rtc_alarm_supported(int fd)
+{
+ struct rtc_param param = { 0 };
+ int rc;
+ char buf[1024] = { 0 };
+
+ /* Validate kernel reflects unsupported RTC alarm state */
+ param.param = RTC_PARAM_FEATURES;
+ param.index = 0;
+ rc = ioctl(fd, RTC_PARAM_GET, &param);
+ if (rc < 0) {
+ /* Fallback to read rtc procfs */
+ fd = open(rtc_procfs, O_RDONLY);

I think I was clear on the previous thread, no new users of the procfs
interface. You can carry this n your own tree but that can't be
upstream.


Okay ~ If we use RTC_PARAM_GET ioctl to detect rtc feature only, not
sure if that is okay for upstream ?

Thank you,
Joseph.