Commit Graph

845 Commits

Author SHA1 Message Date
Michael S. Tsirkin
1d1f19cfce IB/mthca: Give reserved MTTs a separate cache line
MTTs are allocated in non-cache-coherent memory, so we must give
reserved MTTs their own cache line, to prevent both device and
CPU from writing into the same cache line at the same time.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-12 16:16:29 -08:00
Michael S. Tsirkin
c7d204e8fd IB/mthca: Fix reserved MTTs calculation on mem-free HCAs
The reserved_mtts field has different meaning in Tavor and Arbel, so
we are wasting mtt entries on memfree. Fix the Arbel case to match
Tavor semantics.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-12 16:16:29 -08:00
Steve Wise
b038ced7b3 RDMA/cxgb3: Add driver for Chelsio T3 RNIC
Add an RDMA/iWARP driver for the Chelsio T3 1GbE and 10GbE adapters.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-12 16:16:18 -08:00
Sean Hefty
c7f743a669 IB: Remove redundant "_wq" from workqueue names
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-10 08:00:50 -08:00
Sean Hefty
aedec08050 RDMA/cma: Increment port number after close to avoid re-use
Randomize the starting port number and avoid re-using port values
immediately after they are closed.  Instead keep track of the last
port value used and increment it every time a new port number is
assigned, to better replicate other port spaces.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-10 08:00:50 -08:00
Akinobu Mita
65e5c02621 IB/ehca: Fix memleak on module unloading
Percpu data is not freed on module unloading.

Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christoph Raisch <raisch@de.ibm.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-10 08:00:49 -08:00
David Howells
6bdd61d876 IB/mthca: Work around gcc bug on sparc64
For some reason gcc-3.4.5 on sparc64 does:

 WARNING: "____ilog2_NaN" [drivers/infiniband/hw/mthca/ib_mthca.ko] undefined!

Points to note:

 (1) The asm volatile flush/flushw are just markers for viewing what comes out
     in the assembly; removing them has no effect on the result.

 (2) Changing almost anything else in dwh__mthca_arbel_init_srq_context() or
     dwh__mthca_alloc_srq() causes the problem to go away.

The compiler command line issued by the kernel build is:

/opt/crosstool/gcc-3.4.5-glibc-2.3.6/sparc64-unknown-linux-gnu/bin/sparc64-unknown-linux-gnu-gcc -fno-strict-aliasing -fno-common -Os -m64 -mno-fpu -mcpu=ultrasparc -mcmodel=medlow -ffixed-g4 -ffixed-g5 -fcall-used-g7 -Wa,--undeclared-regs -pg -fno-omit-frame-pointer -fno-optimize-sibling-calls -fasynchronous-unwind-tables -g  -c -o drivers/infiniband/hw/mthca/.tmp_mthca_srq.o drivers/infiniband/hw/mthca/mthca_srq.c

This can be reduced to this whilst still retaining the problem:

/opt/crosstool/gcc-3.4.5-glibc-2.3.6/sparc64-unknown-linux-gnu/bin/sparc64-unknown-linux-gnu-gcc -m64 -c -o drivers/infiniband/hw/mthca/mthca_srq.o drivers/infiniband/hw/mthca/mthca_srq.c -Os

Removing -Os or changing it to -O or -O0 thru -O6 gets rid of the problem.

This patch to the kernel code fixes the problem:

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-10 08:00:49 -08:00
Michael S. Tsirkin
839fcaba35 IPoIB: Connected mode experimental support
The following patch adds experimental support for IPoIB connected
mode, as defined by the draft from the IETF ipoib working group.  The
idea is to increase performance by increasing the MTU from the maximum
of 2K (theoretically 4K) supported by IPoIB on top of UD.  With this
code, I'm able to get 800MByte/sec or more with netperf without
options on a Mellanox 4x back-to-back DDR system.

Some notes on code:
1. SRQ is used for scalability to large cluster sizes
2. Only RC connections are used (UC does not support SRQ now)
3. Retry count is set to 0 since spec draft warns against retries
4. Each connection is used for data transfers in only 1 direction, so
   each connection is either active(TX) or passive (RX).  2 sides that
   want to communicate create 2 connections.
5. Each active (TX) connection has a separate CQ for send completions -
   this keeps the code simple without CQ resize and other tricks
6. To detect stale passive side connections (where the remote side is
   down), we keep an LRU list of passive connections (updated once per
   second per connection) and destroy a connection after it has been
   unused for several seconds. The LRU rule makes it possible to avoid
   scanning connections that have recently been active.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-10 08:00:48 -08:00
Ahmed S. Darwish
9a6b090c0d IB/core: Use ARRAY_SIZE macro for mandatory_table
Use ARRAY_SIZE() macro already defined in kernel.h instead of open
coding equivalent code.

Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-10 08:00:47 -08:00
Roland Dreier
99d4f22e91 IB/mthca: Use correct structure size in call to memset()
When clearing the ib_ah_attr parameter in to_ib_ah_attr(), use sizeof
*ib_ah_attr instead of sizeof *path.

Pointed out by Jack Morgenstein <jackm@mellanox.co.il>.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-10 08:00:47 -08:00
Al Viro
b437735645 [PATCH] iscsi endianness annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-09 09:14:07 -08:00
Greg Kroah-Hartman
43cb76d91e Network: convert network devices to use struct device instead of class_device
This lets the network core have the ability to handle suspend/resume
issues, if it wants to.

Thanks to Frederik Deweerdt <frederik.deweerdt@gmail.com> for the arm
driver fixes.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 10:37:11 -08:00
Hoang-Nam Nguyen
b45bfcc1ae IB/ehca: Remove obsolete prototypes
Remove prototypes for functions that don't exist.

Signed-off-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-04 14:11:58 -08:00
Hoang-Nam Nguyen
4c34bdf58c IB/ehca: Remove use of do_mmap()
This patch removes do_mmap() from ehca:
 - Call remap_pfn_range() for hardware register block
 - Use vm_insert_page() to register memory allocated for completion
   queues and queue pairs
 - The actual mmap() call/trigger is now controlled by user space,
   ie. libehca

Signed-off-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-04 14:11:57 -08:00
Steve Wise
1f12667021 RDMA/addr: Handle ethernet neighbour updates during route resolution
The iWARP connection manager uses the ib_addr services to do route
resolution (neighbour discovery in the IP world).  The ib_addr
netevent callback routine, however, currently only acts on InfiniBand
neighbour updates.  It needs to act on ethernet neighbour updates as
well.

This patch just removes filtering on device type altogether and will
trigger on any neighour updates where the nud_type is valid.  This
simplifies the code some.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-04 14:11:57 -08:00
Ishai Rabinovitz
1033ff670d IB/srp: Don't wait for response when QP is in error state.
When there is a call to send_tsk_mgmt SRP posts a send and waits for 5
seconds to get a response.

When the QP is in the error state it is obvious that there will be no
response so it is quite useless to wait.  In fact, the timeout causes
SRP to wait a long time to reconnect when a QP error occurs. (Each
abort and each reset_device calls send_tsk_mgmt, which waits for the
timeout).  The following patch solves this problem by identifying the
failure and returning an immediate error code.

Signed-off-by: Ishai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-04 14:11:56 -08:00
Michael S. Tsirkin
062dbb69f3 IB: Return qp pointer as part of ib_wc
struct ib_wc currently only includes the local QP number: this matches
the IB spec, but seems mostly useless. The following patch replaces
this with the pointer to qp itself, and updates all low level drivers
and all users.

This has the following advantages:
- Ability to get a per-qp context through wc->qp->qp_context
- Existing drivers already have the qp pointer ready in poll cq, so
  this change actually saves a tiny bit (extra memory read) on data path
  (for ehca it would actually be expensive to find the QP pointer when
  polling a CQ, but ehca does not support SRQ so we can leave wc->qp as
  NULL for ehca)
- Users that need the QP number can still get it through wc->qp->qp_num

Use case:

In IPoIB connected mode code, I have a common CQ shared by multiple
QPs.  To track connection usage, I need a way to get at some per-QP
context upon the completion, and I would like to avoid allocating
context object per work request just to stick a QP pointer into it.
With this code, I can just use wc->qp->qp_context.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-04 14:11:55 -08:00
Hoang-Nam Nguyen
cea9ea67e9 IB/ehca: Fix mismatched spin_unlock in irq handler
The lock is taken with _irqsave and hence must be released with
_irqrestore on all paths.

Signed-off-by Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-22 17:03:55 -08:00
Hoang-Nam Nguyen
ce29d72cc7 IB/ehca: Fix improper use of yield() with spinlock held
Signed-off-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-22 17:03:55 -08:00
Ishai Rabinovitz
a20f3a6d7e IB/srp: Check match_strdup() return
Checks if the kmalloc in match_strdup() was successful, and bail out
on looking at the token if it failed.

Signed-off-by: Ishai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-22 17:03:54 -08:00
Dotan Barak
f5e10529a9 IB/mthca: Don't execute QUERY_QP firmware command for QP in RESET state
If a QP being queried is in the RESET state, don't execute the
QUERY_QP firmware command (because it will fail).

Signed-off-by: Dotan Barak <dotanb@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-09 14:14:28 -08:00
Hoang-Nam Nguyen
f2d9136133 IB/ehca: Use proper GFP_ flags for get_zeroed_page()
Here is a patch for ehca to use proper flag, ie. GFP_ATOMIC
resp. GFP_KERNEL, when calling get_zeroed_page() to prevent "Bug:
scheduling while atomic...". This error does not cause a kernel panic
but makes ipoib un-usable afterwards.  It is reproducible on
2.6.20-rc4 if one does ifconfig down during a flood ping test.  I have
not observed this error in earlier releases incl. 2.6.20-rc1.

This error occurs when a qp event/irq is received and ehca event
handler allocates a control block/page to obtain HCA error data block.
Use of GFP_ATOMIC when in interrupt context prevents this issue.

Signed-off-by Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-09 14:14:24 -08:00
Jack Morgenstein
98714cb161 IB/mthca: Fix PRM compliance problem in atomic-send completions
According to the Tavor and Arbel programmer's reference manuals, the
number of bytes transferred is not provided in the byte_cnt field of
the CQ entry for atomic operation completions.  For atomic operations,
the number of bytes transferred is always 8 (when the status is
"success"), and this constant value should always be used by the
driver in the ib_wc entry returned, rather than using the CQE.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-07 20:25:24 -08:00
Sean Hefty
0cefcf0bbc RDMA/ucma: Don't report events with invalid user context
There's a problem with how rdma cm events are reported to userspace
that can lead to application crashes.

When a new connection request arrives, a context for the connection is
allocated in the kernel.  The connection event is then reported to
userspace.  The userspace library retrieves the event and allocates
its own context for the connection.  The userspace context is
associated with the kernel's context when accepting.  This allows the
kernel to give userspace context with other events.

A problem occurs if a second event for the same connection occurs
before the user has had a chance to call accept.  The userspace
context has not yet been set, which causes the librdmacm to crash.
(This has been seen when the app takes too long to call accept,
resulting in the remote side timing out and rejecting the connection)

Fix this by ignoring events for new connections until userspace has
set their context.  This can only happen if an error occurs on a new
connection before the user accepts it.  This is okay, since the accept
will just fail later.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-07 20:20:08 -08:00
Sean Hefty
30a5ec982e RDMA/ucma: Fix struct ucma_event leak when backlog is full
We discard new connection requests while the listen backlog is full,
but leak a struct ucma_event in the process.  Free the structure in
this case.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-07 20:17:34 -08:00
Steve Wise
881a045fc5 RDMA/iwcm: iWARP connection timeouts shouldn't be reported as rejects
The iWARP CM should report timeouts as event RDMA_CM_EVENT_UNREACHABLE,
not event RDMA_CM_EVENT_REJECTED.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-07 20:15:58 -08:00
Erez Zilber
f0938401f2 IB/iser: Return error code when PDUs may not be sent
iSER limits the number of outstanding PDUs to send. When this threshold
is reached, it should return an error code (-ENOBUFS) instead of setting
the suspend_tx bit (which should be used only by libiscsi).

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-07 10:15:15 -08:00
Michael S. Tsirkin
46707e96b7 IB/mthca: Fix off-by-one in FMR handling on memfree
mthca_table_find() will return the wrong address when the table entry
being searched for is exactly at the beginning of a sglist entry
(other than the first), because it uses >= when it should use >.

Example: assume we have 2 entries in scatterlist, 4K each, offset is
4K.  The current code will return first entry + 4K when we really want
the second entry.

In particular this means mapping an FMR on a memfree HCA may end up
writing the page table into the wrong place, leading to memory
corruption and also causing the HCA to use an incorrect address
translation table.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-04 19:46:32 -08:00
Michael S. Tsirkin
9d79f1b467 [PATCH] IB/mthca: Fix FMR breakage caused by kmemdup() conversion
Commit bed8bdfd ("IB: kmemdup() cleanup") introduced one bad conversion to
kmemdup() in mthca_alloc_fmr(), where the structure allocated and the
structure copied are not the same size.  Revert this back to the original
kmalloc()/memcpy() code.

Reported-by: Dotan Barak <dotanb@mellanox.co.il>.
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <roland@digitalvampire.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-30 10:55:55 -08:00
Roland Dreier
0b0df6f207 IB/mthca: Use DEFINE_MUTEX() instead of mutex_init()
mthca_device_mutex() can be initialized automatically with
DEFINE_MUTEX() rather than explicitly calling mutex_init().  This
saves a bit of text and shrinks the source by a line, so we may as
well do it....

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-15 20:55:28 -08:00
Leonid Arsh
82da703ee6 IB/mthca: Add HCA profile module parameters
Add module parameters that enable settting some of the HCA
profile values, such as the number of QPs, CQs, etc.

Signed-off-by: Leonid Arsh <leonida@voltaire.com>
Signed-off-by: Moni Shoua <monis@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-15 20:46:31 -08:00
Roland Dreier
bf628dc22a IB/srp: Fix FMR mapping for 32-bit kernels and addresses above 4G
struct srp_device.fmr_page_mask was unsigned long, which means that
the top part of addresses above 4G was being chopped off on 32-bit
architectures.  Of course nothing good happens when data from SRP
targets is DMAed to the wrong place.

Fix this by changing fmr_page_mask to u64, to match the addresses
actually used by IB devices.

Thanks to Brian Cain <Brian.Cain@ge.com> and David McMillen
<davem@systemfabricworks.com> for help diagnosing the bug and testing
the fix.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-15 14:01:49 -08:00
Roland Dreier
82b399133b IPoIB: Make sure struct ipoib_neigh.queue is always initialized
Move the initialization of ipoib_neigh's skb_queue into
ipoib_neigh_alloc(), since commit 2745b5b7 ("IPoIB: Fix skb leak when
freeing neighbour") will make iterate over the skb_queue to free any
packets left over when freeing the ipoib_neigh structure.

This fixes a crash when freeing ipoib_neigh structures allocated in
ipoib_mcast_send(), which otherwise don't have their skb_queue
initialized.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 14:48:18 -08:00
Ralph Campbell
5180311fe9 IB/iser: Use the new verbs DMA mapping functions
Convert iSER to use the new verbs DMA mapping functions for kernel
verbs consumers.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 14:31:00 -08:00
Ralph Campbell
85507bcce0 IB/srp: Use new verbs IB DMA mapping functions
Convert SRP to use the new verbs DMA mapping functions for kernel
verbs consumers.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 14:30:55 -08:00
Ralph Campbell
37ccf9df97 IPoIB: Use the new verbs DMA mapping functions
Convert IPoIB to use the new DMA mapping functions
for kernel verbs consumers.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 14:30:48 -08:00
Ralph Campbell
1527106ff8 IB/core: Use the new verbs DMA mapping functions
Convert code in core/ to use the new DMA mapping functions for kernel
verbs consumers.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 14:28:30 -08:00
Ralph Campbell
f2cbb660ed IB/ipath: Implement new verbs DMA mapping functions
This patch implements the interposing DMA mapping functions to allow
support for IOMMUs and remove the dependence on phys_to_virt() and
bus_to_virt().

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 14:28:28 -08:00
Sean Hefty
7521663857 RDMA/cma: Export rdma cm interface to userspace
Export the rdma cm interfaces to userspace via a misc device.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:22 -08:00
Sean Hefty
628e5f6d39 RDMA/cma: Add support for RDMA_PS_UDP
Allow the use of UD QPs through the rdma_cm, in order to provide
address translation services for resolving IB addresses for datagram
messages using SIDR.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:21 -08:00
Sean Hefty
0fe313b000 RDMA/cma: Allow early transition to RTS to handle lost CM messages
During connection establishment, the passive side of a connection can
receive messages from the active side before the connection event has
been delivered to the user.  Allow the passive side to send messages
in response to received data before the event is delivered.  To handle
the case where the connection messages are lost, a new rdma_notify()
function is added that users may invoke to force a connection into the
established state.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:21 -08:00
Sean Hefty
a1b1b61f80 RDMA/cma: Report connect info with connect events
Connection information was never given to the recipient of a
connection request or reply message.  Only the event was delivered.
Report the connection data with the event to allows user to
reject the connection based on the requested parameters, or adjust
their resources to match the request.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:21 -08:00
Sean Hefty
9b2e9c0c24 RDMA/cma: Remove unneeded qp_type parameter from rdma_cm
The qp_type parameter into the rdma_cm is unneeded, and can be
misleading.  The QP type should be determined from the port space.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:21 -08:00
Roland Dreier
0a1336c8c9 IB/ipath: Fix IRQ for PCI Express HCAs
Commit 51f65ebc ("IB/ipath - program intconfig register using new HT
irq hook"), which fixed interrupts for HyperTransport HCAs, broke PCI
Express HCAs, because for those HCAs, the driver uses the value of
pdev->irq before pci_enable_msi() and ends up getting a totally bogus
IRQ number.  Fix this by using the value of pdev->irq after
pci_enable_msi().

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:20 -08:00
Krishna Kumar
ad1f9791e9 RDMA/amso1100: Fix memory leak in c2_qp_modify()
vq_req is leaked in error cases.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:20 -08:00
Roland Dreier
dee234f48a IB/iser: Remove unused "write-only" variables
Remove variables that are set but then never looked at in the iSER
initiator.  These cleanups came from David Binderman's list of "set
but never used" warnings from icc.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:20 -08:00
Roland Dreier
44f8e3f3f7 IB/ipath: Remove unused "write-only" variables
Remove variables that are set but then never looked at in the ipath
driver.  These cleanups came from David Binderman's list of "set but
never used" warnings from icc.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:20 -08:00
Roland Dreier
f47e22c6e4 IB/fmr: ib_flush_fmr_pool() may wait too long
ib_flush_fmr_pool() stashes away the request generation number
properly, but then goes ahead and rereads it every time it tests
whether the flush generation number has caught up.  This means that
there is a theoretical possibility of livelock, if the request
generation number keeps getting bumped and the flush generation number
never catches up.  The fix is simple: use the request generation
number read at the beginning of the function.

Also, atomic_inc() followed by atomic_read() can be replaced with
atomic_int_return().  There's no real requirement for atomicity here
but we might as well shrink the code.

This bug was discovered using David Binderman's list of "set but never
used" warnings from icc.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-12-12 11:50:19 -08:00
David Howells
f0d1b0b30d [PATCH] LOG2: Implement a general integer log2 facility in the kernel
This facility provides three entry points:

	ilog2()		Log base 2 of unsigned long
	ilog2_u32()	Log base 2 of u32
	ilog2_u64()	Log base 2 of u64

These facilities can either be used inside functions on dynamic data:

	int do_something(long q)
	{
		...;
		y = ilog2(x)
		...;
	}

Or can be used to statically initialise global variables with constant values:

	unsigned n = ilog2(27);

When performing static initialisation, the compiler will report "error:
initializer element is not constant" if asked to take a log of zero or of
something not reducible to a constant.  They treat negative numbers as
unsigned.

When not dealing with a constant, they fall back to using fls() which permits
them to use arch-specific log calculation instructions - such as BSR on
x86/x86_64 or SCAN on FRV - if available.

[akpm@osdl.org: MMC fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Wojtek Kaniewski <wojtekka@toxygen.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:51 -08:00
Josef Sipek
1cfd6e648b [PATCH] struct path: convert infiniband
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:46 -08:00