Commit graph

20 commits

Author SHA1 Message Date
Shannon Nelson
e422397634 [IOAT]: ioatdma needs to to play nice in a multi-dma-client world
Now that the DMA engine has a multi-client interface, fix the ioatdma
driver to play along.  At the same time, remove a couple of unnecessary
reads and writes.

Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-26 18:35:40 -07:00
Shannon Nelson
54a09feb0e [IOAT]: Remove redundant struct member to avoid descriptor cache miss
The layout for struct ioat_desc_sw is non-optimal and causes an extra
cache hit for every descriptor processed.  By tightening up the struct
layout and removing one item, we pull in the fields that get used in
the speedpath and get a little better performance.


Before:
-------
struct ioat_desc_sw {
	struct ioat_dma_descriptor * hw;                 /*     0     8
*/
	struct list_head           node;                 /*     8    16
*/
	int                        tx_cnt;               /*    24     4
*/

	/* XXX 4 bytes hole, try to pack */

	dma_addr_t                 src;                  /*    32     8
*/
	__u32                      src_len;              /*    40     4
*/

	/* XXX 4 bytes hole, try to pack */

	dma_addr_t                 dst;                  /*    48     8
*/
	__u32                      dst_len;              /*    56     4
*/

	/* XXX 4 bytes hole, try to pack */

	/* --- cacheline 1 boundary (64 bytes) --- */
	struct dma_async_tx_descriptor async_tx;         /*    64   144
*/
	/* --- cacheline 3 boundary (192 bytes) was 16 bytes ago --- */

	/* size: 208, cachelines: 4 */
	/* sum members: 196, holes: 3, sum holes: 12 */
	/* last cacheline: 16 bytes */
};	/* definitions: 1 */


After:
------

struct ioat_desc_sw {
	struct ioat_dma_descriptor * hw;                 /*     0     8
*/
	struct list_head           node;                 /*     8    16
*/
	int                        tx_cnt;               /*    24     4
*/
	__u32                      len;                  /*    28     4
*/
	dma_addr_t                 src;                  /*    32     8
*/
	dma_addr_t                 dst;                  /*    40     8
*/
	struct dma_async_tx_descriptor async_tx;         /*    48   144
*/
	/* --- cacheline 3 boundary (192 bytes) --- */

	/* size: 192, cachelines: 3 */
};	/* definitions: 1 */


Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-14 17:36:31 -07:00
Dan Williams
3039f0735a ioatdma: add the unisys "i/oat" pci vendor/device id
Cc: John Magolan <john.magolan@unisys.com>
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2007-07-13 08:06:19 -07:00
Dan Williams
d379b01e90 dmaengine: make clients responsible for managing channels
The current implementation assumes that a channel will only be used by one
client at a time.  In order to enable channel sharing the dmaengine core is
changed to a model where clients subscribe to channel-available-events.
Instead of tracking how many channels a client wants and how many it has
received the core just broadcasts the available channels and lets the
clients optionally take a reference.  The core learns about the clients'
needs at dma_event_callback time.

In support of multiple operation types, clients can specify a capability
mask to only be notified of channels that satisfy a certain set of
capabilities.

Changelog:
* removed DMA_TX_ARRAY_INIT, no longer needed
* dma_client_chan_free -> dma_chan_release: switch to global reference
  counting only at device unregistration time, before it was also happening
  at client unregistration time
* clients now return dma_state_client to dmaengine (ack, dup, nak)
* checkpatch.pl fixes
* fixup merge with git-ioat

Cc: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
2007-07-13 08:06:13 -07:00
Dan Williams
7405f74bad dmaengine: refactor dmaengine around dma_async_tx_descriptor
The current dmaengine interface defines mutliple routines per operation,
i.e. dma_async_memcpy_buf_to_buf, dma_async_memcpy_buf_to_page etc.  Adding
more operation types (xor, crc, etc) to this model would result in an
unmanageable number of method permutations.

	Are we really going to add a set of hooks for each DMA engine
	whizbang feature?
		- Jeff Garzik

The descriptor creation process is refactored using the new common
dma_async_tx_descriptor structure.  Instead of per driver
do_<operation>_<dest>_to_<src> methods, drivers integrate
dma_async_tx_descriptor into their private software descriptor and then
define a 'prep' routine per operation.  The prep routine allocates a
descriptor and ensures that the tx_set_src, tx_set_dest, tx_submit routines
are valid.  Descriptor creation and submission becomes:

struct dma_device *dev;
struct dma_chan *chan;
struct dma_async_tx_descriptor *tx;

tx = dev->device_prep_dma_<operation>(chan, len, int_flag)
tx->tx_set_src(dma_addr_t, tx, index /* for multi-source ops */)
tx->tx_set_dest(dma_addr_t, tx, index)
tx->tx_submit(tx)

In addition to the refactoring, dma_async_tx_descriptor also lays the
groundwork for definining cross-channel-operation dependencies, and a
callback facility for asynchronous notification of operation completion.

Changelog:
* drop dma mapping methods, suggested by Chris Leech
* fix ioat_dma_dependency_added, also caught by Andrew Morton
* fix dma_sync_wait, change from Andrew Morton
* uninline large functions, change from Andrew Morton
* add tx->callback = NULL to dmaengine calls to interoperate with async_tx
  calls
* hookup ioat_tx_submit
* convert channel capabilities to a 'cpumask_t like' bitmap
* removed DMA_TX_ARRAY_INIT, no longer needed
* checkpatch.pl fixes
* make set_src, set_dest, and tx_submit descriptor specific methods
* fixup git-ioat merge
* move group_list and phys to dma_async_tx_descriptor

Cc: Jeff Garzik <jeff@garzik.org>
Cc: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
2007-07-13 08:06:11 -07:00
Dan Aloni
428ed6024f I/OAT: fix I/OAT for kexec
Under kexec, I/OAT initialization breaks over busy resources because the
previous kernel did not release them.

I'm not sure this fix can be considered a complete one but it works for me.
 I guess something similar to the *_remove method should occur there..

Signed-off-by: Dan Aloni <da-x@monatomic.org>
Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2007-07-11 16:10:53 -07:00
Chris Leech
70774b4739 ioatdma: Remove the use of writeq from the ioatdma driver
There's only one now anyway, and it's not in a performance path,
so make it behave the same on 32-bit and 64-bit CPUs.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
2007-07-11 15:39:04 -07:00
Chris Leech
e38288117c ioatdma: Remove the wrappers around read(bwl)/write(bwl) in ioatdma
Signed-off-by: Chris Leech <christopher.leech@intel.com>
2007-07-11 15:39:04 -07:00
Chris Leech
000725d56a ioatdma: Push pending transactions to hardware more frequently
Every 20 descriptors turns out to be to few append commands with
newer/faster CPUs.  Pushing every 4 still cuts down on MMIO writes to an
acceptable level without letting the DMA engine run out of work.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
2007-07-11 15:39:03 -07:00
Randy Dunlap
92504f79a7 IOATDMA: fix section mismatches
Rename struct pci_driver data so that false section mismatch warnings won't
be produced.

Sam, ISTM that depending on variable names is the weakest & worst part of
modpost section checking.  Should __init_refok work here?  I got build
errors when I tried to use it, probably because the struct pci_driver probe
and remove methods are not marked "__init_refok".

WARNING: drivers/dma/ioatdma.o(.data+0x10): Section mismatch: reference to .init.text: (between 'ioat_pci_drv' and 'ioat_pci_tbl')
WARNING: drivers/dma/ioatdma.o(.data+0x14): Section mismatch: reference to .exit.text: (between 'ioat_pci_drv' and 'ioat_pci_tbl')

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Chris Leech <christopher.leech@intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-28 11:34:53 -07:00
Christoph Lameter
e94b176609 [PATCH] slab: remove SLAB_KERNEL
SLAB_KERNEL is an alias of GFP_KERNEL.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:24 -08:00
Al Viro
47b16539e1 [PATCH] drivers/dma trivial annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-10 15:37:21 -07:00
David Howells
7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00
Henrik Kretzschmar
b826315813 [I/OAT]: Remove pci_module_init() from Intel I/OAT DMA engine
Changes pci_module_init() to pci_register_driver().

Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-21 14:50:13 -07:00
Randy Dunlap
6508871edd [IOAT]: fix kernel-doc in source files
Fix kernel-doc warnings in drivers/dma/:
- use correct function & parameter names
- add descriptions where omitted

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-03 19:45:31 -07:00
Benoit Boissinot
518d1c9679 [IOAT]: Fix a warning in ioatdma
drivers/dma/ioatdma.c: In function 'ioat_init_module':
drivers/dma/ioatdma.c:830: warning: control reaches end of non-void function

Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-03 19:28:13 -07:00
Thomas Gleixner
dace145374 [PATCH] irq-flags: misc drivers: Use the new IRQF_ constants
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 13:58:50 -07:00
David S. Miller
8070b2b1ec [IOAT]: Do not dereference THIS_MODULE directly to set unsafe.
Use the __unsafe() macro instead.

Noticed by Miles Lane.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-26 00:10:46 -07:00
David S. Miller
6b00c92c4b [I/OAT]: ioatdma.c needs linux/dma-mapping.h
For DMA_*_MASK defines.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:18:48 -07:00
Chris Leech
0bbd5f4e97 [I/OAT]: Driver for the Intel(R) I/OAT DMA engine
Adds a new ioatdma driver

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:18:46 -07:00