The __get_txreq() function can return a pointer, ERR_PTR(-EBUSY), or NULL.
All of the relevant call sites look for IS_ERR, so the NULL return would
lead to a NULL pointer exception.
Do not use the ERR_PTR mechanism for this function.
Update all call sites to handle the return value correctly.
Clean up error paths to reflect return value.
Fixes: 45842abbb2 ("staging/rdma/hfi1: move txreq header code")
Cc: <stable@vger.kernel.org> # 4.9.x+
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Kamenee Arumugam <kamenee.arumugam@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Performance analysis shows that the cache callback function
sdma_kmem_cache_ctor contributes to 1/2 of the kmem_cache_allocs
time.
Since all of the fields in the allocated data structure are initialized
in the code path, remove the _ctor function.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug 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: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This improves readability and hides the reference count
mechanism from the client drivers.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
A failure in the get_txreq() inline will result in a
slow path retry using __get_txreq().
__get_txreq() attempts to procure the qp s_lock, which
is already held in all callers.
Fix by deleting the s_lock maintenance in __get_txreq()
and add sparse syntax hooks to future proof the code.
Cc: Stable <stable@vger.kernel.org> # 4.6+
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug 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: Jubin John <jubin.john@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Cai Huoqing