diff options
| author |   Nicholas Piggin <npiggin@gmail.com> | 2018-05-05 03:19:30 +1000 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2018-06-03 20:40:27 +1000 |
| commit | 3d3a6021ddcbe9c31520e4e7b65e5ce5dc58274d (patch) | |
| tree | 10d300ac9f4f3b8354b9e35075d3d5a776739e7e /drivers/misc/ocxl/context.c | |
| parent | powerpc/64: remove start_tb and accum_tb from thread_struct (diff) | |
| download | linux-dev-3d3a6021ddcbe9c31520e4e7b65e5ce5dc58274d.tar.xz linux-dev-3d3a6021ddcbe9c31520e4e7b65e5ce5dc58274d.zip | |
powerpc/pseries: lparcfg calculate PURR on demand
For SPLPAR, lparcfg provides a sum of PURR registers for all CPUs.
Currently this is done by reading PURR in context switch and timer
interrupt, and storing that into a per-CPU variable. These are summed
to provide the value.
This does not work with all timer schemes (e.g., NO_HZ_FULL), and it
is sub-optimal for performance because it reads the PURR register on
every context switch, although that's been difficult to distinguish
from noise in the contxt_switch microbenchmark.
This patch implements the sum by calling a function on each CPU, to
read and add PURR values of each CPU.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'drivers/misc/ocxl/context.c')
0 files changed, 0 insertions, 0 deletions