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  1. 28 Jun, 2017 14 commits
  3. 27 Jun, 2017 10 commits
  5. 23 Jun, 2017 1 commit
    • Balbir Singh's avatar
      powerpc/mm: Trace tlbie(l) instructions · 0428491c
      Balbir Singh authored 
      Add a trace point for tlbie(l) (Translation Lookaside Buffer Invalidate
Entry (Local)) instructions.

The tlbie instruction has changed over the years, so not all versions
accept the same operands. Use the ISA v3 field operands because they are
the most verbose, we may change them in future.

Example output:

  qemu-system-ppc-5371  [016]  1412.369519: tlbie:
  	tlbie with lpid 0, local 1, rb=67bd8900174c11c1, rs=0, ric=0 prs=0 r=0
Signed-off-by: default avatarBalbir Singh <bsingharora@gmail.com>
[mpe: Add some missing trace_tlbie()s, reword change log]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      0428491c
  7. 22 Jun, 2017 1 commit
    • Paul Mackerras's avatar
      powerpc: Convert VDSO update function to use new update_vsyscall interface · d4cfb113
      Paul Mackerras authored 
      This converts the powerpc VDSO time update function to use the new
interface introduced in commit 576094b7 ("time: Introduce new
GENERIC_TIME_VSYSCALL", 2012-09-11).  Where the old interface gave
us the time as of the last update in seconds and whole nanoseconds,
with the new interface we get the nanoseconds part effectively in
a binary fixed-point format with tk->tkr_mono.shift bits to the
right of the binary point.

With the old interface, the fractional nanoseconds got truncated,
meaning that the value returned by the VDSO clock_gettime function
would have about 1ns of jitter in it compared to the value computed
by the generic timekeeping code in the kernel.

The powerpc VDSO time functions (clock_gettime and gettimeofday)
already work in units of 2^-32 seconds, or 0.23283 ns, because that
makes it simple to split the result into seconds and fractional
seconds, and represent the fractional seconds in either microseconds
or nanoseconds.  This is good enough accuracy for now, so this patch
avoids changing how the VDSO works or the interface in the VDSO data
page.

This patch converts the powerpc update_vsyscall_old to be called
update_vsyscall and use the new interface.  We convert the fractional
second to units of 2^-32 seconds without truncating to whole nanoseconds.
(There is still a conversion to whole nanoseconds for any legacy users
of the vdso_data/systemcfg stamp_xtime field.)

In addition, this improves the accuracy of the computation of tb_to_xs
for those systems with high-frequency timebase clocks (>= 268.5 MHz)
by doing the right shift in two parts, one before the multiplication and
one after, rather than doing the right shift before the multiplication.
(We can't do all of the right shift after the multiplication unless we
use 128-bit arithmetic.)
Signed-off-by: default avatarPaul Mackerras <paulus@ozlabs.org>
Acked-by: default avatarJohn Stultz <john.stultz@linaro.org>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      d4cfb113
  9. 21 Jun, 2017 4 commits
  11. 20 Jun, 2017 9 commits
  13. 19 Jun, 2017 1 commit
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