These values were introduced as part of the 16B code to
account for the varying size of the LRH between the differing
packet formats.

Replace the blind constants with defines based on FIELD_SIZEOF()
calls.

Fixes: 5b6cabb0 ("IB/hfi1: Add 16B RC/UC support")
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

In the receive path, hfi1_ibport is looked up by indexing into an
array. A profile shows this to be expensive. The receive context
data has a pointer to the ibport data, use that pointer instead.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NSebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The packet type comparison used to find out if a packet is a bypass
packet in the hot path is an expensive operation as seen in a profile.

Determine packet's pkey and migration bit through the bypass and 9B
code paths instead.
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NSebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The s_hdrwords variable was used to indicate whether a
packet was already built on a previous iteration of the
send engine. This variable assumed the protection of the
QP's RVT_S_BUSY flag, which was required since the the
QP's s_lock was dropped just prior to the packet being
queued on the one of the egress mechanisms.

Support for multiple send engine instantiations require
that the field not be used due to concurency issues.
The ps.txreq signals the "already built" without the
potential concurency issues.

Fix by getting rid of all s_hdrword usage.   A wrapper
is added to test for the already built case that used to
use s_hdrwords.

What used to be stored in s_hdrwords is now in the txreq.
The PBC is not counted, but is added in the pio/sdma code
paths prior to posting the packet.
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Remove HFI1_VERBS_31BIT_PSN Kconfig option leaving only 31-bit PSNs
available. The option was implemented in the early days of the driver
and is no longer needed.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NGrzegorz Morys <grzegorz.morys@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

PIO/SDMA send logic now uses the hdr_type field to determine
the type of packet that has been constructed. Based on the hdr_type,
certain things such as PBC flags, padding count and the LT extra
trailing bytes are determined.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add 16B bypass packet support for RC/UC traffic types.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Increase lid used in hfi1 driver to 32 bits. qib continues
to use 16 bit lids.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add 16B bypass packet support for UD traffic types.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When address handle attributes are initialized, the LIDs are
transformed to be in the 32 bit LID space.
When constructing the header, hfi1 driver will look at the LID
to determine the packet header to be created.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Enhance hdr_rcverr() to also handle errors during
16B bypass packet receive.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

We introduce struct hfi1_opa_header as a union
of ib (9B) and 16B headers.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

We introduce a struct hfi1_16b_header to support 16B headers.
16B bypass packets are received by the driver and processed
similar to 9B packets. Add basic support to handle 16B packets.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When an egress resource(SDMA descriptors, pio credits) is not available,
a sending thread will be put on the resource's wait queue. When the
resource becomes available again, up to a fixed number of sending threads
can be awakened sequentially and removed from the wait queue, depending
on the number of waiting threads and the number of free resources. Since
each awakened sending thread will send as many packets as possible, it
is highly likely that the first sending thread will consume all the
egress resources. Subsequently, it will be put back to the end of the wait
queue. Depending on the timing when the later sending threads wake up,
they may not be able to send any packet and be again put back to the end
of the wait queue sequentially, right behind the first sending thread.
This starvation cycle continues until some sending threads exceed their
retry limit and consequently fail.

This patch fixes the issue by two simple approaches:
(1) Any starved sending thread will be put to the head of the wait queue
while a served sending thread will be put to the tail;
(2) The most starved sending thread will be served first.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NKaike Wan <kaike.wan@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

According to IBTA spec a QKey violation should not result in a bad qkey
trap being triggered for UD queue pairs. Also since it is a silent error
we do not increment the q_key violation or the dropped packet counters.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

We move many common IB fields into the hfi1_packet structure and
set them up in a single function. This allows us to set the fields
in a single place and not deal with them throughout the driver.
Reviewed-by: NBrian Welty <brian.welty@intel.com>
Reviewed-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When there are many RC QPs and an RDMA READ request
is sent, timeouts occur on the requester side because
of fairness among RC QPs on their relative SDMA engine
on the responder side.  This also hits write and send, but
to a lesser extent.

Complicating the issue is that the current code checks if workqueue
is congested before scheduling other QPs, however, this
check is based on the number of active entries in the
workqueue, which was found to be too big to for
workqueue_congested() to be effective.

Fix by reducing the number of active entries as revealed by
experimentation from the default of num_sdma to
HFI1_MAX_ACTIVE_WORKQUEUE_ENTRIES.  Retry counts were monitored
to determine the correct value.

Tracing to investigate any future issues is also added.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NSebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This field is causing excessive cache line bouncing.

There are spare bytes in the r_lock cache line so the best approach
is to make an rvt QP field and remove from the hfi1 priv field.
Signed-off-by: NSebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Modify core and driver components to use accessor functions
introduced to access individual fields of rdma_ah_attr
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Reviewed-by: NSean Hefty <sean.hefty@intel.com>
Reviewed-by: NNiranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch simply renames struct ib_ah_attr to
rdma_ah_attr as these fields specify attributes that are
not necessarily specific to IB.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Reviewed-by: NNiranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Reviewed-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The driver progress routines can call cond_resched() when
a timeslice is exhausted and irqs are enabled.

If the ULP had been holding a spin lock without disabling irqs and
the post send directly called the progress routine, the cond_resched()
could yield allowing another thread from the same ULP to deadlock
on that same lock.

Correct by replacing the current hfi1_do_send() calldown with a unique
one for post send and adding an argument to hfi1_do_send() to indicate
that the send engine is running in a thread.   If the routine is not
running in a thread, avoid calling cond_resched().

CC: <stable@vger.kernel.org> # 4.7.x-
Fixes: Commit 831464ce ("IB/hfi1: Don't call cond_resched in atomic mode when sending packets")
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add ability to fault packets on transmit by opcode.
Dropping by packet can be achieved by setting the mask to 0.

In order to drop non-verbs traffic we set PbcInsertHrc
to NONE (0x2). The packet will still be delivered to
the receiving node but a KHdrHCRCErr (KDETH packet
with a bad HCRC) will be triggered and the packet will
not be delivered to the correct context.

In order to drop regular verbs traffic we set the
PbcTestEbp flag. The packet will still be delivered
to the receiving node but a 'late ebp error' will
be triggered and will be dropped.

A global toggle (/sys/kernel/debug/hfi1/hfi1_X/fault_suppress_err)
has been added to suppress the error messages on the receive
node when a packet was faulted on the sending node.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add fault injection capability:
  - Drop packets unconditionally (fault_by_packet)
  - Drop packets based on opcode (fault_by_opcode)

This feature reacts to the global FAULT_INJECTION
config flag.

The faulting traces have been added:
  - misc/fault_opcode
  - misc/fault_packet

See 'Documentation/fault-injection/fault-injection.txt'
for details.

Examples:
  - Dropping packets by opcode:
    /sys/kernel/debug/hfi1/hfi1_X/fault_opcode
	# Enable fault
	echo Y > fault_by_opcode
	# Setprobability of dropping (0-100%)
	# echo 25 > probability
	# Set opcode
	echo 0x64 > opcode
	# Number of times to fault
	echo 3 > times
	# An optional mask allows you to fault
	# a range of opcodes
	echo 0xf0 > mask
    /sys/kernel/debug/hfi1/hfi1_X/fault_stats
    contains a value in parentheses to indicate
    number of each opcode dropped.

  - Dropping packets unconditionally
    /sys/kernel/debug/hfi1/hfi1_X/fault_packet
	# Enable fault
	echo Y > fault_by_packet
    /sys/kernel/debug/hfi1/hfi1_X/fault_packet/fault_stats
    contains the number of packets dropped.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

To improve code reuse, add small SGE state helper routines to rdmavt_mr.h.
Leverage these in hfi1, including refactoring of hfi1_copy_sge.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NBrian Welty <brian.welty@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Convert copy_sge and related SGE state functions to use boolean.
For determining if QP is in user mode, add helper function in rdmavt_qp.h.
This is used to determine if QP needs the last byte ordering.
While here, change rvt_pd.user to a boolean.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NBrian Welty <brian.welty@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Reduce hfi1 code footprint by using the rdmavt timers.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NBrian Welty <brian.welty@intel.com>
Signed-off-by: NVenkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add rvt_compute_aeth() and rvt_get_credit() as shared functions in
rdmavt, moved from hfi1/qib logic.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NBrian Welty <brian.welty@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add rvt_rc_error() and rvt_comm_est() as shared functions in
rdmavt, moved from hfi1/qib logic.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NBrian Welty <brian.welty@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch consolidates the node GUIDs and the port GUID handling
and unifies access to these items. The knowledge of hfi1 GUIDs'
design and their location are kept in accessors to centralize access.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NBrian Welty <brian.welty@intel.com>
Signed-off-by: NJakub Pawlak <jakub.pawlak@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Profiling suggests that the read_seqbegin() in
the txreq put logic is colliding with other uses
of the iowait lock.

The packet at a time use of this lock dictates a unique
lock to avoid reader/writer collisions when the number
of vTxWait events is low.

In order to support a unique lock the iowait struct embedded
in the QP is extended to remember the lock that protects the queue
head.

The QP destroy removes that QP from any wait list.  It doesn't
need to know the head because of the linked list API, but it does
need to know the lock required to protect the head.

This also opens up the wait logic to have unique per resources locks
which needs to be in future refinement.
Reviewed-by: NSebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This allows for adding additional pages of adaptive pio
opcode control including manufacturer specific ones.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Use common header file structs, defines, and accessors
in the drivers.  The old declarations are removed.

The repositioning of the includes allows for the removal
of hfi1_message_header and replaces its use with ib_header.

Also corrected are two issues with set_armed_to_active():
- The "packet" parameter is now a pointer as it should have been
- The etype is validated to insure that the header is correct
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

hfi1_pio_header should really be called hfi1_sdma_header
as it is only used for sdma transmits.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

struct ahg_ib_header has no header specific information.
Rename it to struct hfi1_ahg_info
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

sde and hfi1_ib_header are not used anymore.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

A new union member "ieth" (Invalidate Extended Transport Header) is
added to the packet header definition in preparation of supporting
the send with invalidate opcode.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJianxin Xiong <jianxin.xiong@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The TODO list for the hfi1 driver was completed during 4.6. In addition
other objections raised (which are far beyond what was in the TODO list)
have been addressed as well. It is now time to remove the driver from
staging and into the drivers/infiniband sub-tree.
Reviewed-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The awkward coding for setting the allowed_ops field
was tripping an smatch warning.

This patch uses the more appropriate defines from include/rdma
to avoid the issue.

As part of the patch remove a mask that was duplicated
in rdmavt include files and use that mask as appropriate.

Fixes: 8bea6b1cfe6f ("IB/rdmavt: Add create queue pair functionality")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The dual lock patch moved locking around and missed an issue
with handling irq flags when processing UD loopback
packets.  This issue was revealed by smatch.

Fix for both qib and hfi1 to pass the saved flags to the UD request
builder and handle the changes correctly.

Fixes: 46a80d62 ("IB/qib, staging/rdma/hfi1: add s_hlock for use in post send")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The kernel memcpy is faster than a cacheless copy.  However,
if too much of the L3 cache is overwritten by one-time copies
then overall bandwidth suffers.  Implement an adaptive scheme
where full page copies are tracked and if the number of unique
entries are larger than a threshold, verbs will use a cacheless
copy.  Tracked entries are gradually cleaned, allowing memcpy to
resume once the larger copies have stopped.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>