Sergei Trofimovich aa06a9bd85 ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency ... clock_gettime(CLOCK_MONOTONIC, &tp) is very precise on ia64 as it uses ITC (similar to rdtsc on x86). It's not quite a hrtimer as it is a few times slower than 1ns. Usually 2-3ns. clock_getres(CLOCK_MONOTONIC, &res) never reflected that fact and reported 0.04s precision (1/HZ value). In https://bugs.gentoo.org/596382 gstreamer's test suite failed loudly when it noticed precision discrepancy. Before the change: clock_getres(CLOCK_MONOTONIC, &res) reported 250Hz precision. After the change: clock_getres(CLOCK_MONOTONIC, &res) reports ITC (400Mhz) precision. The patch is based on matoro's fix. I added a bit of explanation why we need to special-case arch-specific clock_getres(). [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/20220820181813.2275195-1-slyich@gmail.com Signed-off-by: Sergei Trofimovich <slyich@gmail.com> Cc: matoro <matoro_mailinglist_kernel@matoro.tk> Cc: Émeric Maschino <emeric.maschino@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>		2022-09-11 21:55:07 -07:00
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Makefile	arch: syscalls: simplify uapi/kapi directory creation	2022-03-31 12:03:46 +09:00
syscall.tbl	ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency	2022-09-11 21:55:07 -07:00