typo fix in last commit
b=10800
i=shadow
i=green

Sync log_commit_thread count between llog_commit_thread_start and
llog_commit_thread_cleanup.
b=10800
i=shadow
i=green

land 10800(adding llog ctxt refcount) to b1_6.
b=10800
i=green
i=shadow

To improve performance, disable most logging (for debug purposes)
by default.  VFSTRACE, RPCTRACE, and DLMTRACE are now off by
default, and HA includes contains fewer messages.

Original patch by adilger.

b=12417
i=scjody
i=green

r=wangdi,adigler

Take import reference before releasing llog record semaphore

 - add a flag in lustre_msg which indicate message type
 - add a security descriptor into most of messages send to MDSs, which
   include the uid, supplementary groups array etc.
 - add group hash
 - MDS retrive local groups database through upcall, and set/merge with
   which sent from client based on policies (here not totally finished)
 - move root_squash test into separate sanity-sec.sh

r=rread
A quick workaround for bug 3652, in which we hold the logging
semaphore across an rpc.  Robert thinks that this file can be cleaned
up substantially, but that this fix is sufficient for CMD.

I haven't re-tested the AMD functionality since landing, but I did
test iozone and dbench to ensure sanity.

b_cmobd_merge should not be used for any further development or testing!

cMD_PRE_CMD_SMASH are the relevant tags.

The pre-smashing contents of HEAD will be committed by yury into b_cmd as a
merge of the two branches.  These will be stabilized on b_cmd and eventually
landed onto HEAD.

b=3043, b=3258, b=3219, b=2410

b=2733, b=2773, b=2529, b=2730, b=2819, b=2814, b=2822, b=1450, b=2676, b=2681
b=2817, b=2706, b=2816, b=1987, b=2884, b=1191, b=2809, b=2765, b=2805, b=1972

 - dozens and dozens of fixes for working with 2.6 kernels
 - new 2.4 kernel APIs
 - uncountable bug fixes