2 Commits

Author	SHA1	Message	Date
Alexandre Belloni	5546e3dfb6	rtc: lib_test: add MODULE_LICENSE ... As the documentation states, "The exact license information can only be determined via the license information in the corresponding source files." and the SPDX identifier has the proper information. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20210810212008.631359-1-alexandre.belloni@bootlin.com	2021-08-10 23:21:46 +02:00
Cassio Neri	1d1bb12a8b	rtc: Improve performance of rtc_time64_to_tm(). Add tests. ... The current implementation of rtc_time64_to_tm() contains unnecessary loops, branches and look-up tables. The new one uses an arithmetic-based algorithm appeared in [1] and is approximately 4.3 times faster (YMMV). The drawback is that the new code isn't intuitive and contains many 'magic numbers' (not unusual for this type of algorithm). However, [1] justifies all those numbers and, given this function's history, the code is unlikely to need much maintenance, if any at all. Add a KUnit test case that checks every day in a 160,000 years interval starting on 1970-01-01 against the expected result. Add a new config RTC_LIB_KUNIT_TEST symbol to give the option to run this test suite. [1] Neri, Schneider, "Euclidean Affine Functions and Applications to Calendar Algorithms". https://arxiv.org/abs/2102.06959 Signed-off-by: Cassio Neri <cassio.neri@gmail.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20210624201343.85441-1-cassio.neri@gmail.com	2021-08-10 00:09:21 +02:00