diff options
Diffstat (limited to 'sys/kern/kern_ffclock.c')
| -rw-r--r-- | sys/kern/kern_ffclock.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/sys/kern/kern_ffclock.c b/sys/kern/kern_ffclock.c index 4d31c40..62b91f4 100644 --- a/sys/kern/kern_ffclock.c +++ b/sys/kern/kern_ffclock.c @@ -30,14 +30,29 @@ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); +#include "opt_ffclock.h" + #include <sys/param.h> +#include <sys/bus.h> +#include <sys/kernel.h> +#include <sys/lock.h> +#include <sys/module.h> +#include <sys/mutex.h> +#include <sys/priv.h> +#include <sys/proc.h> #include <sys/sbuf.h> +#include <sys/sysent.h> +#include <sys/sysproto.h> #include <sys/sysctl.h> #include <sys/systm.h> #include <sys/timeffc.h> +#ifdef FFCLOCK + extern struct ffclock_estimate ffclock_estimate; extern struct bintime ffclock_boottime; +extern int8_t ffclock_updated; +extern struct mtx ffclock_mtx; /* * Feed-forward clock absolute time. This should be the preferred way to read @@ -208,6 +223,12 @@ sysctl_kern_ffclock_active(SYSCTL_HANDLER_ARGS) SYSCTL_PROC(_kern_ffclock, OID_AUTO, active, CTLTYPE_STRING | CTLFLAG_RW, 0, 0, sysctl_kern_ffclock_active, "A", "Kernel clock selected"); +int sysctl_kern_ffclock_ffcounter_bypass = 0; + +SYSCTL_INT(_kern_ffclock, OID_AUTO, ffcounter_bypass, CTLFLAG_RW, + &sysctl_kern_ffclock_ffcounter_bypass, 0, + "Use reliable hardware timecounter as the Feed-Forward Counter"); + /* * High level functions to access the Feed-Forward Clock. */ @@ -341,3 +362,112 @@ ffclock_microdifftime(ffcounter ffdelta, struct timeval *tvp) ffclock_difftime(ffdelta, &bt, NULL); bintime2timeval(&bt, tvp); } + +/* + * System call allowing userland applications to retrieve the current value of + * the Feed-Forward Clock counter. + */ +#ifndef _SYS_SYSPROTO_H_ +struct ffclock_getcounter_args { + ffcounter *ffcount; +}; +#endif +/* ARGSUSED */ +int +sys_ffclock_getcounter(struct thread *td, struct ffclock_getcounter_args *uap) +{ + ffcounter ffcount; + int error; + + ffcount = 0; + ffclock_read_counter(&ffcount); + if (ffcount == 0) + return (EAGAIN); + error = copyout(&ffcount, uap->ffcount, sizeof(ffcounter)); + + return (error); +} + +/* + * System call allowing the synchronisation daemon to push new feed-foward clock + * estimates to the kernel. Acquire ffclock_mtx to prevent concurrent updates + * and ensure data consistency. + * NOTE: ffclock_updated signals the fftimehands that new estimates are + * available. The updated estimates are picked up by the fftimehands on next + * tick, which could take as long as 1/hz seconds (if ticks are not missed). + */ +#ifndef _SYS_SYSPROTO_H_ +struct ffclock_setestimate_args { + struct ffclock_estimate *cest; +}; +#endif +/* ARGSUSED */ +int +sys_ffclock_setestimate(struct thread *td, struct ffclock_setestimate_args *uap) +{ + struct ffclock_estimate cest; + int error; + + /* Reuse of PRIV_CLOCK_SETTIME. */ + if ((error = priv_check(td, PRIV_CLOCK_SETTIME)) != 0) + return (error); + + if ((error = copyin(uap->cest, &cest, sizeof(struct ffclock_estimate))) + != 0) + return (error); + + mtx_lock(&ffclock_mtx); + memcpy(&ffclock_estimate, &cest, sizeof(struct ffclock_estimate)); + ffclock_updated++; + mtx_unlock(&ffclock_mtx); + return (error); +} + +/* + * System call allowing userland applications to retrieve the clock estimates + * stored within the kernel. It is useful to kickstart the synchronisation + * daemon with the kernel's knowledge of hardware timecounter. + */ +#ifndef _SYS_SYSPROTO_H_ +struct ffclock_getestimate_args { + struct ffclock_estimate *cest; +}; +#endif +/* ARGSUSED */ +int +sys_ffclock_getestimate(struct thread *td, struct ffclock_getestimate_args *uap) +{ + struct ffclock_estimate cest; + int error; + + mtx_lock(&ffclock_mtx); + memcpy(&cest, &ffclock_estimate, sizeof(struct ffclock_estimate)); + mtx_unlock(&ffclock_mtx); + error = copyout(&cest, uap->cest, sizeof(struct ffclock_estimate)); + return (error); +} + +#else /* !FFCLOCK */ + +int +sys_ffclock_getcounter(struct thread *td, struct ffclock_getcounter_args *uap) +{ + + return (ENOSYS); +} + +int +sys_ffclock_setestimate(struct thread *td, struct ffclock_setestimate_args *uap) +{ + + return (ENOSYS); +} + +int +sys_ffclock_getestimate(struct thread *td, struct ffclock_getestimate_args *uap) +{ + + return (ENOSYS); +} + +#endif /* FFCLOCK */ |
