ORI-729 mount: Print more helpful message on EBUSY

If the mount function returns EBUSY, there is a chance that the
backend filesystem is mounted through the Posix layer. Specifically,
when using a ZFS backend EBUSY will be returned in this use case. As an
aid the to end user, this patch prints a message intended to help the
user diagnose and fix the issue.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Change-Id: If75c144be3974313a48d011616400553c7176327
LU-1576 llite: correct page usage count

If kernel has add_to_page_cache_lru(), the ll_pagevec_add() is defined
as an empty function, while page_cache_get(page) only makes sense if
ll_pagevec_add() is defined.

This patch moves page_cache_get into ll_pagevec_add() macro
definition.

Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Change-Id: Iad98aacff43beec3e7a64fd1a778f549250aa5b8
LU-1442 llite: cleanup if a page failed to add into cache

In lustre, we assume that a dirty page must be queued in osc cache
for writing. However, in vvp_io_commit_write(), if a page failed to
add into cache, page dirty flag isn't cleared this will cause the
page will never be added into cache again.

Signed-off-by: Jinshan Xiong <jinshan.xiong@whamcloud.com>
Change-Id: I4e2eb61d25e97daf9d32ba2f5c57223d77763b5b
Patch-Set: 1
Revert "LU-744 osc: add lru pages management - new RPC"

This reverts commit 7a79d73523dc607abe48e10f8e8a6b2c2c36a187.
LU-744 llite: reimplement ll_get_fsname()

ll_get_fsname() used to allocate a piece of memory to store fsname,
this is not needed and error prone because it requires the caller
to free that piece of memory.

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Change-Id: Ibc077b46728a1358e51a345ec13c966fc947c428
LU-744 osc: add lru pages management - new RPC

Add a cache management at osc layer, this way we can control how much
memory can be used to cache lustre pages and avoid complex solution
as what we did in b1_8.

In this patch, admins can set how much memory will be used for caching
lustre pages per file system. A self-adapative algorithm is used to
balance those budget among OSCs.

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Change-Id: I76c840aef5ca9a3a4619f06fcaee7de7f95b05f5
LU-1666 obdclass: reduce lock contention on coh_page_guard

Define a per-page spinlock to get and put a cl_page instead of
grabbing per-object lock coh_page_guard.

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Change-Id: Iecf5e6840ab1a28edcf2c4bcde6a72c2f9b5bdae
Add o2iblnd histograms in /proc

One histogram is for time spent on the ibc_active_txs queue by transmit
packets.  Tells us how long it took the IB layer to actually send
a message once Lustre hands it off.

Another histrogram shows time that the kib_conn_t is sitting on the
kib_sched_list queue.

Signed-off-by: Christopher J. Morrone <morrone2@llnl.gov>
b=14494 Debugging for o2iblnd RDMA timeouts

Add debugging information that will hopefully prove useful when
we hit the "Timed out RDMA with" IB timeouts.

Contributions-by: Isaac Huang <he.huang@sun.com>
Contributions-by: Christopher J. Morrone <morrone2@llnl.gov>
Add socklnd histograms in /proc

Histogram of time tx messages spend queued waiting to be written to the
underlying socket.

Signed-off-by: Christopher J. Morrone <morrone2@llnl.gov>
socklnd additional debugging
Change the path for iblnd histograms

The previous paths used for the iblnd histograms were causing errors as
the directory creation was failing. To resolve this, the paths were
changed and a pointer to the root directory is passed to the
create_proc_entry calls.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Change-Id: I27ba7ff556916fcb067ada5b03d8530731f3b8c1
LU-1742 o2iblnd: Fix up the 'Timed out tx' message

The message printed for a timed out transaction in the o2iblnd code was
modified to provide more useful information to the end user. This should
(hopefully) give more insight into the problem, while simultaneously
making the message more "human friendly".

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Change-Id: Ied40db9ce5483bc8929116c6d720f2a8e078c0f9