From baa73d9e478ff32d62f3f9422822b59dd9a95a21 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Fri, 11 Nov 2016 00:10:10 -0500 Subject: posix-timers: Make them configurable Some embedded systems have no use for them. This removes about 25KB from the kernel binary size when configured out. Corresponding syscalls are routed to a stub logging the attempt to use those syscalls which should be enough of a clue if they were disabled without proper consideration. They are: timer_create, timer_gettime: timer_getoverrun, timer_settime, timer_delete, clock_adjtime, setitimer, getitimer, alarm. The clock_settime, clock_gettime, clock_getres and clock_nanosleep syscalls are replaced by simple wrappers compatible with CLOCK_REALTIME, CLOCK_MONOTONIC and CLOCK_BOOTTIME only which should cover the vast majority of use cases with very little code. Signed-off-by: Nicolas Pitre Acked-by: Richard Cochran Acked-by: Thomas Gleixner Acked-by: John Stultz Reviewed-by: Josh Triplett Cc: Paul Bolle Cc: linux-kbuild@vger.kernel.org Cc: netdev@vger.kernel.org Cc: Michal Marek Cc: Edward Cree Link: http://lkml.kernel.org/r/1478841010-28605-7-git-send-email-nicolas.pitre@linaro.org Signed-off-by: Thomas Gleixner --- arch/alpha/kernel/osf_sys.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch/alpha') diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index ffb93f499c83..56e427c7aa3c 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -1029,11 +1029,16 @@ SYSCALL_DEFINE2(osf_settimeofday, struct timeval32 __user *, tv, return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL); } +asmlinkage long sys_ni_posix_timers(void); + SYSCALL_DEFINE2(osf_getitimer, int, which, struct itimerval32 __user *, it) { struct itimerval kit; int error; + if (!IS_ENABLED(CONFIG_POSIX_TIMERS)) + return sys_ni_posix_timers(); + error = do_getitimer(which, &kit); if (!error && put_it32(it, &kit)) error = -EFAULT; @@ -1047,6 +1052,9 @@ SYSCALL_DEFINE3(osf_setitimer, int, which, struct itimerval32 __user *, in, struct itimerval kin, kout; int error; + if (!IS_ENABLED(CONFIG_POSIX_TIMERS)) + return sys_ni_posix_timers(); + if (in) { if (get_it32(&kin, in)) return -EFAULT; -- cgit v1.2.3-70-g09d2