osd: l_osd_tier_promote

Signed-off-by: Sage Weil <sage@inktank.com>
osd: l_osd_copyfrom

Signed-off-by: Sage Weil <sage@inktank.com>
osd: l_osd_tier_[try_]flush[_fail]

Signed-off-by: Sage Weil <sage@inktank.com>
osd: l_osd_tier_evict

Signed-off-by: Sage Weil <sage@inktank.com>
osd: l_osd_tier_whiteout

Signed-off-by: Sage Weil <sage@inktank.com>
osd: l_osd_tier_[dirty|clean]

Signed-off-by: Sage Weil <sage@inktank.com>
osd: l_osd_agent_{wake,skip,flush,evict}

Signed-off-by: Sage Weil <sage@inktank.com>
osd/ReplicatedPG: clean up agent skip debug output

Signed-off-by: Sage Weil <sage@inktank.com>
Merge pull request #1255 from ceph/wip-cache-perf

osd: add perfcounters for new cache and agent events

Reviewed-by: Haomai Wang <haomaiwang@gmail.com>