erasure-code: allow loading a plugin from factory()

The Mutex scope is restricted to only protect the load() method and not
the factory() method. This allows a plugin to load another plugin from
within the factory() method.

Reviewed-By: Christophe Courtaut <christophe.courtaut@gmail.com>
Signed-off-by: Loic Dachary <loic@dachary.org>
erasure-code: gf-complete / jerasure modules updates

To avoid confusion, the jerasure v1 branch that contains commits pending
review upstream is named v2-ceph and the gf-complete v2 branch is named
v2-ceph.

Signed-off-by: Loic Dachary <loic@dachary.org>
autotools: intel cpu features detection

Rename SIMD to INTEL for clarity.

Instead of agregating all flags in INTEL_FLAGS, create individual flags
for each feature (INTEL_SSE2_FLAGS etc.) for finer control in the
makefiles.

Signed-off-by: Loic Dachary <loic@dachary.org>
arch: add SSE3, SSSE3, SSSE41 and PCLMUL intel features

And add a note about valgrind forcing a fake cpuid.

Signed-off-by: Loic Dachary <loic@dachary.org>
erasure-code: SSE optimized jerasure plugins

The jerasure plugin is compiled with three sets of flags:

* jerasure_generic with no SSE optimization
* jerasure_sse3 with SSE2, SSE3 and SSSE3 optimizations
* jerasure_sse4 with SSE2, SSE3, SSSE3, SSE41, SSE42 and PCLMUL optimizations

The jerasure plugin loads the appropriate plugin depending on the CPU
features detected at runtime.

http://tracker.ceph.com/issues/7826 fixes #7826

Signed-off-by: Loic Dachary <loic@dachary.org>
osd: increase osd verbosity during functional tests

Signed-off-by: Loic Dachary <loic@dachary.org>
erasure-code: test jerasure SSE optimized plugins selection

Test the selection of the plugin depending on the CPU features. The
prefix of the plugin is "jerasure" by default (jerasure_generic,
jerasure_sse3, jerasure_sse4) and can be modified with the
"jerasure-name" parameter. A test plugin is created for each
variant (test_jerasure_generic, test_jerasure_sse3, test_jerasure_sse4).
The flags set by ceph_probe are modified by the test to check if the
expected plugin suffix is appended.

Signed-off-by: Loic Dachary <loic@dachary.org>
erasure-code: test encode/decode of SSE optimized jerasure plugins

If the machine running make check has the required CPU features
available, load the SSE optimized plugin and check that it can encode /
decode a simple payload. If the CPU features are not available, only
test the generic plugin and display an informative message about the
tests that were skipped.

Signed-off-by: Loic Dachary <loic@dachary.org>