android_kernel_xiaomi_sm8350/arch/powerpc/kernel/vdso64
Paul Mackerras 597bc5c00b powerpc: Improve resolution of VDSO clock_gettime
Currently the clock_gettime implementation in the VDSO produces a
result with microsecond resolution for the cases that are handled
without a system call, i.e. CLOCK_REALTIME and CLOCK_MONOTONIC.  The
nanoseconds field of the result is obtained by computing a
microseconds value and multiplying by 1000.

This changes the code in the VDSO to do the computation for
clock_gettime with nanosecond resolution.  That means that the
resolution of the result will ultimately depend on the timebase
frequency.

Because the timestamp in the VDSO datapage (stamp_xsec, the real time
corresponding to the timebase count in tb_orig_stamp) is in units of
2^-20 seconds, it doesn't have sufficient resolution for computing a
result with nanosecond resolution.  Therefore this adds a copy of
xtime to the VDSO datapage and updates it in update_gtod() along with
the other time-related fields.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-11-06 09:49:22 +11:00
..
.gitignore [POWERPC] Update .gitignore for new vdso generated files 2007-10-08 08:38:12 -05:00
cacheflush.S [POWERPC] vdso: Fixes for cache block sizes 2007-11-20 13:56:31 +11:00
datapage.S
gettimeofday.S powerpc: Improve resolution of VDSO clock_gettime 2008-11-06 09:49:22 +11:00
Makefile [POWERPC] powerpc vDSO: install unstripped copies on disk 2007-10-03 12:02:43 +10:00
note.S
sigtramp.S [POWERPC] Fix 64 bits vDSO DWARF info for CR register 2007-10-17 22:30:09 +10:00
vdso64_wrapper.S
vdso64.lds.S powerpc: Fixup lwsync at runtime 2008-07-03 16:58:10 +10:00