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15 commits

Author SHA1 Message Date
Maciej Sosnowski
c419fcfd07 dca: check against empty dca_domains list before unregister provider
When providers get blocked unregister_dca_providers() is called ending up
with dca_providers and dca_domain lists emptied. Dca should be prevented from
trying to unregister any provider if dca_domain list is found empty.

Cc: <stable@vger.kernel.org>
Reported-by: Jiang Liu <jiang.liu@huawei.com>
Tested-by: Gaohuai Han <hangaohuai@huawei.com>
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <djbw@fb.com>
2013-01-07 22:05:14 -08:00
Paul Gortmaker
d229807f66 drivers/dca: Add module.h to dca-core.c
This file really needs the full module.h header file present, but
was just getting it implicitly before.  Call it out in advance so
that we don't get future build failures on this.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:43 -04:00
Mike Galbraith
a1741e7fcb locking, drivers/dca: Annotate dca_lock as raw
The dca_lock can be taken in atomic context:

[   25.607536] Call Trace:
[   25.607557]  [<ffffffff820078a1>] try_stack_unwind+0x151/0x1a0
[   25.607566]  [<ffffffff820062c2>] dump_trace+0x92/0x370
[   25.607573]  [<ffffffff8200731c>] show_trace_log_lvl+0x5c/0x80
[   25.607578]  [<ffffffff82007355>] show_trace+0x15/0x20
[   25.607587]  [<ffffffff823f4588>] dump_stack+0x77/0x8f
[   25.607595]  [<ffffffff82043f2a>] __might_sleep+0x11a/0x130
[   25.607602]  [<ffffffff823f7b93>] rt_spin_lock+0x83/0x90
[   25.607611]  [<ffffffffa0209138>] dca_common_get_tag+0x28/0x80 [dca]
[   25.607622]  [<ffffffffa02091c8>] dca3_get_tag+0x18/0x20 [dca]
[   25.607634]  [<ffffffffa0244e71>] igb_update_dca+0xb1/0x1d0 [igb]
[   25.607649]  [<ffffffffa0244ff5>] igb_setup_dca+0x65/0x80 [igb]
[   25.607663]  [<ffffffffa02535a6>] igb_probe+0x946/0xe4d [igb]
[   25.607678]  [<ffffffff82247517>] local_pci_probe+0x17/0x20
[   25.607686]  [<ffffffff82248661>] pci_device_probe+0x121/0x130
[   25.607699]  [<ffffffff822e4832>] driver_probe_device+0xd2/0x2e0
[   25.607707]  [<ffffffff822e4adb>] __driver_attach+0x9b/0xa0
[   25.607714]  [<ffffffff822e3d1b>] bus_for_each_dev+0x6b/0xa0
[   25.607720]  [<ffffffff822e4591>] driver_attach+0x21/0x30
[   25.607727]  [<ffffffff822e3425>] bus_add_driver+0x1e5/0x350
[   25.607734]  [<ffffffff822e4e41>] driver_register+0x81/0x160
[   25.607742]  [<ffffffff8224890f>] __pci_register_driver+0x6f/0xf0
[   25.607752]  [<ffffffffa011505b>] igb_init_module+0x5b/0x5d [igb]
[   25.607769]  [<ffffffff820001dd>] do_one_initcall+0x3d/0x1a0
[   25.607778]  [<ffffffff820961f6>] sys_init_module+0xe6/0x270
[   25.607786]  [<ffffffff82003232>] system_call_fastpath+0x16/0x1b
[   25.607794]  [<00007f84d6783f4a>] 0x7f84d6783f4a

and thus must not be preempted on -rt.

In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.

Signed-off-by: Mike Galbraith <efault@gmx.de>
[ Fixed the domain allocation which was calling kzalloc from the irq disabled section ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13 11:12:12 +02:00
Kirill A. Shutemov
3bb598fb23 drivers/dca/dca-core.c: use list_move() instead of list_del()/list_add() combination
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:12 -07:00
Dan Carpenter
f0f2c2b5b4 dca: remove unneeded NULL check
The return here doesn't release the locks or re-enable IRQs.  But as
Andrew Morton points out, domain is never NULL.  list_first_entry()
essentially never returns NULL and also we already verified that the list
is not empty.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:09 -08:00
Sosnowski, Maciej
4e8cec269d dca: disable dca on IOAT ver.3.0 multiple-IOH platforms
Direct Cache Access is not supported on IOAT ver.3.0 multiple-IOH platforms.
This patch blocks registering of dca providers when multiple IOH detected with IOAT ver.3.0.

Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-17 20:08:21 -07:00
Tejun Heo
5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Stephen Hemminger
084dac53ad dca: module load should not be an error message
The message (if it must exist) should not be an error message.
IMHO such messages are useless.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-13 10:27:04 -07:00
Maciej Sosnowski
1a5aeeecd5 dca: registering requesters in multiple dca domains
This patch enables DCA support on multiple-IOH/multiple-IIO architectures.
It modifies dca module by replacing single dca_providers list
with dca_domains list, each domain containing separate list of providers.
This approach lets dca driver manage multiple domains, i.e. sets of providers
and requesters mapped back to the same PCI root complex device.
The driver takes care to register each requester to a provider
from the same domain.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
2009-09-10 10:00:05 -07:00
Maciej Sosnowski
211a22ce08 I/OAT: update driver version and copyright dates
Together with new fixes update driver version
and extend copyright dates ranges.

Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04 16:04:40 -07:00
Maciej Sosnowski
eb4400e3a0 dca: redesign locks to fix deadlocks
Change spin_locks to irqsave to prevent dead-locks.
Protect adding and deleting to/from dca_providers list.
Drop the lock during dca_sysfs_add_req() and dca_sysfs_remove_req() calls
as they might sleep (use GFP_KERNEL allocation).

Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-02 23:26:57 -08:00
Dan Williams
652afc27b2 dmaengine: bump initcall level to arch_initcall
There are dmaengine users that would like to register dma devices at
subsys_initcall time to ensure channels are available by device_initcall
time.

Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06 11:38:22 -07:00
Dan Williams
1207e79556 [4/4] dca: fixup initialization dependency
Mark dca_init as a subsys_initcall since it needs to be ready to go
before dependent drivers start registering themselves.

Cc: <stable@kernel.org>
Reported-and-tested-by: Mark Rustad <mark_rustad@Xiotech.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-10 15:01:03 -08:00
Maciej Sosnowski
7f1b358a23 I/OAT: I/OAT version 3.0 support
This patch adds to ioatdma and dca modules
support for Intel I/OAT DMA engine ver.3 (aka CB3 device).
The main features of I/OAT ver.3 are:
 * 8 single channel DMA devices (8 channels total)
 * 8 DCA providers, each can accept 2 requesters
 * 8-bit TAG values and 32-bit extended APIC IDs

Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-22 17:30:57 -07:00
Shannon Nelson
7589670f37 DCA: Add Direct Cache Access driver
Direct Cache Access (DCA) is a method for warming the CPU cache before data
is used, with the intent of lessening the impact of cache misses.  This
patch adds a manager and interface for matching up client requests for DCA
services with devices that offer DCA services.

In order to use DCA, a module must do bus writes with the appropriate tag
bits set to trigger a cache read for a specific CPU.  However, different
CPUs and chipsets can require different sets of tag bits, and the methods
for determining the correct bits may be simple hardcoding or may be a
hardware specific magic incantation.  This interface is a way for DCA
clients to find the correct tag bits for the targeted CPU without needing
to know the specifics.

    [Dave Miller] use DEFINE_SPINLOCK()

Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:09 -07:00