History log of /freebsd/sys/i386/include/vdso.h (Results 1 – 6 of 6)
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Revision tags: release/14.0.0
# 71625ec9 16-Aug-2023 Warner Losh <imp@FreeBSD.org>

sys: Remove $FreeBSD$: one-line .c comment pattern

Remove /^/[*/]\s*\$FreeBSD\$.*\n/


Revision tags: release/13.2.0, release/12.4.0, release/13.1.0, release/12.3.0, release/13.0.0, release/12.2.0, release/11.4.0, release/12.1.0, release/11.3.0, release/12.0.0, release/11.2.0, release/10.4.0, release/11.1.0, release/11.0.1, release/11.0.0, release/10.3.0, release/10.2.0, release/10.1.0, release/9.3.0, release/10.0.0, release/9.2.0, release/8.4.0, release/9.1.0
# 23090366 04-Nov-2012 Simon J. Gerraty <sjg@FreeBSD.org>

Sync from head


# de720122 15-Jul-2012 Gleb Smirnoff <glebius@FreeBSD.org>

Merge head r236710 through r238467.


# 6cf87ec8 13-Jul-2012 Xin LI <delphij@FreeBSD.org>

IFC @238412.


# b652778e 11-Jul-2012 Peter Grehan <grehan@FreeBSD.org>

IFC @ r238370


# aea81038 22-Jun-2012 Konstantin Belousov <kib@FreeBSD.org>

Implement mechanism to export some kernel timekeeping data to
usermode, using shared page. The structures and functions have vdso
prefix, to indicate the intended location of the code in some future

Implement mechanism to export some kernel timekeeping data to
usermode, using shared page. The structures and functions have vdso
prefix, to indicate the intended location of the code in some future.

The versioned per-algorithm data is exported in the format of struct
vdso_timehands, which mostly repeats the content of in-kernel struct
timehands. Usermode reading of the structure can be lockless.
Compatibility export for 32bit processes on 64bit host is also
provided. Kernel also provides usermode with indication about
currently used timecounter, so that libc can fall back to syscall if
configured timecounter is unknown to usermode code.

The shared data updates are initiated both from the tc_windup(), where
a fast task is queued to do the update, and from sysctl handlers which
change timecounter. A manual override switch
kern.timecounter.fast_gettime allows to turn off the mechanism.

Only x86 architectures export the real algorithm data, and there, only
for tsc timecounter. HPET counters page could be exported as well, but
I prefer to not further glue the kernel and libc ABI there until
proper vdso-based solution is developed.

Minimal stubs neccessary for non-x86 architectures to still compile
are provided.

Discussed with: bde
Reviewed by: jhb
Tested by: flo
MFC after: 1 month

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