summaryrefslogtreecommitdiffstats
path: root/kernel/spinlock.c
diff options
context:
space:
mode:
authorStefan Richter <stefanr@s5r6.in-berlin.de>2011-04-22 15:13:54 +0200
committerStefan Richter <stefanr@s5r6.in-berlin.de>2011-05-10 22:53:44 +0200
commitf30e6d3e419bfb5540fa82ba7eca01d578556e6b (patch)
treee4d6e7bad161a76b09557bf7513358ae1ce8f7fb /kernel/spinlock.c
parent020abf03cd659388f94cb328e1e1df0656e0d7ff (diff)
downloadblackbird-op-linux-f30e6d3e419bfb5540fa82ba7eca01d578556e6b.tar.gz
blackbird-op-linux-f30e6d3e419bfb5540fa82ba7eca01d578556e6b.zip
firewire: octlet AT payloads can be stack-allocated
We do not need slab allocations anymore in order to satisfy streaming DMA mapping constraints, thanks to commit da28947e7e36 "firewire: ohci: avoid separate DMA mapping for small AT payloads". (Besides, the slab-allocated buffers that firewire-core, firewire-sbp2, and firedtv used to provide for 8-byte write and lock requests were still not fully portable since they crossed cacheline boundaries or shared a cacheline with unrelated CPU-accessed data. snd-firewire-lib got this aspect right by using an extra kmalloc/ kfree just for the 8-byte transaction buffer.) This change replaces kmalloc'ed lock transaction scratch buffers in firewire-core, firedtv, and snd-firewire-lib by local stack allocations. Perhaps the most notable result of the change is simpler locking because there is no need to serialize usages of preallocated per-device buffers anymore. Also, allocations and deallocations are simpler. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Acked-by: Clemens Ladisch <clemens@ladisch.de>
Diffstat (limited to 'kernel/spinlock.c')
0 files changed, 0 insertions, 0 deletions
OpenPOWER on IntegriCloud