Currently, the Galois Field multiplication tables are recalcuated
every time an encode is done. This is wasteful, as they are fixed
by k and m, which is set on init.
Calculate the tables only once, on init.
This trades off a little bit of per-context memory and creation
time for measurably faster encodes when using the same context.
On powerpc64le, when repeatedly encoding a 4kB file with pyeclib,
this increases the measured speed by over 10%.
Change-Id: I2f025aaee2d13cb1717a331e443e179ad5a13302
Signed-off-by: Daniel Axtens <dja@axtens.net>
This is for supporting ISA-L cauchy based matrix. The difference
from isa_l_rs_vand is only the matrix to use the encode/decode calculation.
As a known issue, isa_l_rs_vand backend has constraint for the
combinations of the available fragment to be able to decode/reconstuct.
(See related change in detail)
To avoid the constraint, this patch adds another isa-l backend to use
cauchy matrix and keep the backward compatibility, this is in
another isa_l_rs_cauchy namespace.
For implementation consieration, the code is almost same except the matrix
generation fucntion so that this patch makes isa_l_common.c file for
gathering common fucntions like init/encode/decode/reconstruct. And then the
common init funciton takes an extra args "gen_matrix_func_name" for entry
point to load the fucntion by dlsym from isa-l .so file.
Co-Authored-By: Clay Gerrard <clay.gerrard@gmail.com>
Related-Change: Icee788a0931fe692fe0de31fabc4ba450e338a87
Change-Id: I6eb150d9d0c3febf233570fa7729f9f72df2e9be
Daniel Axtens