linux-toradex.git/net/rds/ib_recv.c, branch v3.2.6

RDS/IB: print string constants in more places

2010-09-09T01:16:50+00:00

This prints the constant identifier for work completion status and rdma
cm event types, like we already do for IB event types.

A core string array helper is added that each string type uses.

Signed-off-by: Zach Brown

RDS: properly use sg_init_table

2010-09-09T01:16:41+00:00

This is only needed to keep debugging code from bugging.

Signed-off-by: Chris Mason

RDS: remove init and exit annotation

2010-09-09T01:16:39+00:00

The trivial amount of memory saved isn't worth the cost of dealing with section
mismatches.

Signed-off-by: Zach Brown

RDS/IB: Use SLAB_HWCACHE_ALIGN flag for kmem_cache_create()

2010-09-09T01:16:38+00:00

We are *definitely* counting cycles as closely as DaveM, so
ensure hwcache alignment for our recv ring control structs.

Signed-off-by: Andy Grover

RDS/IB: always process recv completions

2010-09-09T01:16:36+00:00

The recv refill path was leaking fragments because the recv event handler had
marked a ring element as free without freeing its frag.  This was happening
because it wasn't processing receives when the conn wasn't marked up or
connecting, as can be the case if it races with rmmod.

Two observations support always processing receives in the callback.

First, buildup should only post receives, thus triggering recv event handler
calls, once it has built up all the state to handle them.  Teardown should
destroy the CQ and drain the ring before tearing down the state needed to
process recvs.  Both appear to be true today.

Second, this test was fundamentally racy.  There is nothing to stop rmmod and
connection destruction from swooping in the moment after the conn state was
sampled but before real receive procesing starts.

Signed-off-by: Zach Brown

RDS/IB: Make ib_recv_refill return void

2010-09-09T01:16:31+00:00

Signed-off-by: Andy Grover

RDS: use friendly gfp masks for prefill

2010-09-09T01:15:24+00:00

When prefilling the rds frags, we end up doing a lot of allocations.
We're not in atomic context here, and so there's no reason to dip into
atomic reserves.  This changes the prefills to use masks that allow
waiting.

Signed-off-by: Chris Mason

RDS/IB: Add caching of frags and incs

2010-09-09T01:15:23+00:00

This patch is based heavily on an initial patch by Chris Mason.
Instead of freeing slab memory and pages, it keeps them, and
funnels them back to be reused.

The lock minimization strategy uses xchg and cmpxchg atomic ops
for manipulation of pointers to list heads. We anchor the lists with a
pointer to a list_head struct instead of a static list_head struct.
We just have to carefully use the existing primitives with
the difference between a pointer and a static head struct.

For example, 'list_empty()' means that our anchor pointer points to a list with
a single item instead of meaning that our static head element doesn't point to
any list items.

Original patch by Chris, with significant mods and fixes by Andy and Zach.

Signed-off-by: Chris Mason 
Signed-off-by: Andy Grover 
Signed-off-by: Zach Brown

RDS/IB: Remove ib_recv_unmap_page()

2010-09-09T01:15:22+00:00

All it does is call unmap_sg(), so just call that directly.

The comment above unmap_page also may be incorrect, so we
shouldn't hold on to it, either.

Signed-off-by: Andy Grover

RDS: Assume recv->r_frag is always NULL in refill_one()

2010-09-09T01:15:21+00:00

refill_one() should never be called on a recv struct that
doesn't need a new r_frag allocated. Add a WARN and remove
conditional around r_frag alloc code.

Also, add a comment to explain why r_ibinc may or may not
need refilling.

Signed-off-by: Andy Grover