Commit Graph

9 Commits

Author SHA1 Message Date
Viresh Kumar
ca53d434f7 x86/uv/time: Migrate to new set-state interface
Migrate uv driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

We weren't doing anything while switching modes other than in shutdown
mode and so those are not implemented.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/52e04139746222a2e82a96d13953cbc306cfb59b.1437042675.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-30 21:25:38 +02:00
Christoph Lameter
89cbc76768 x86: Replace __get_cpu_var uses
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x).  This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.

Other use cases are for storing and retrieving data from the current
processors percpu area.  __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.

__get_cpu_var() is defined as :

#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))

__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.

this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.

This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset.  Thereby address calculations are avoided and less registers
are used when code is generated.

Transformations done to __get_cpu_var()

1. Determine the address of the percpu instance of the current processor.

	DEFINE_PER_CPU(int, y);
	int *x = &__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&y);

2. Same as #1 but this time an array structure is involved.

	DEFINE_PER_CPU(int, y[20]);
	int *x = __get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(y);

3. Retrieve the content of the current processors instance of a per cpu
variable.

	DEFINE_PER_CPU(int, y);
	int x = __get_cpu_var(y)

   Converts to

	int x = __this_cpu_read(y);

4. Retrieve the content of a percpu struct

	DEFINE_PER_CPU(struct mystruct, y);
	struct mystruct x = __get_cpu_var(y);

   Converts to

	memcpy(&x, this_cpu_ptr(&y), sizeof(x));

5. Assignment to a per cpu variable

	DEFINE_PER_CPU(int, y)
	__get_cpu_var(y) = x;

   Converts to

	__this_cpu_write(y, x);

6. Increment/Decrement etc of a per cpu variable

	DEFINE_PER_CPU(int, y);
	__get_cpu_var(y)++

   Converts to

	__this_cpu_inc(y)

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:49 -04:00
Alexandru Gheorghiu
e87b686b51 x86/platform/uv: Replace kmalloc() & memset with kzalloc()
This was found using coccicheck.

Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Link: http://lkml.kernel.org/r/1362822043-15559-1-git-send-email-gheorghiuandru@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-03-11 08:33:01 +01:00
Mike Travis
0af6352045 x86, uv, uv3: Update Time Support for SGI UV3
This patch updates time support for the SGI UV3 hub.  Since the UV2
and UV3 time support is identical, "is_uvx_hub" is used instead of
having both "is_uv2_hub" and "is_uv3_hub".

Signed-off-by: Mike Travis <travis@sgi.com>
Link: http://lkml.kernel.org/r/20130211194508.893907185@gulag1.americas.sgi.com
Acked-by: Russ Anderson <rja@sgi.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-11 17:18:12 -08:00
Dimitri Sivanich
b0deca2e02 x86/UV: Lower UV rtc clocksource rating
Lower the rating of the UV rtc clocksource to just below that of
the tsc, to improve performance.

Reading the tsc clocksource has lower latency than reading the
rtc, so favor it in situations where it is synchronized and
stable.  When the tsc is unsynchronized, the rtc needs to be the
chosen clocksource.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Jack Steiner <steiner@sgi.com>
Link: http://lkml.kernel.org/r/20120217141641.GA28063@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-20 09:07:56 +01:00
Jack Steiner
2a919596c1 x86, UV: Add support for SGI UV2 hub chip
This patch adds support for a new version of the SGI UV hub
chip. The hub chip is the node controller that connects multiple
blades into a larger coherent SSI.

For the most part, UV2 is compatible with UV1. The majority of
the changes are in the addresses of MMRs and in a few cases, the
contents of MMRs. These changes are the result in changes in the
system topology such as node configuration, processor types,
maximum nodes, physical address sizes, etc.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Link: http://lkml.kernel.org/r/20110511175028.GA18006@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-25 14:20:13 +02:00
John Stultz
b01cc1b0ea x86: Convert remaining x86 clocksources to clocksource_register_hz/khz
This converts the remaining x86 clocksources to use
clocksource_register_hz/khz.

CC: jacob.jun.pan@intel.com
CC: Glauber Costa <glommer@redhat.com>
CC: Dimitri Sivanich <sivanich@sgi.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Jeremy Fitzhardinge <jeremy@xensource.com>
CC: Chris McDermott <lcm@us.ibm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
2011-02-21 13:33:33 -08:00
Dimitri Sivanich
8191c9f692 x86: UV: Address interrupt/IO port operation conflict
This patch for SGI UV systems addresses a problem whereby
interrupt transactions being looped back from a local IOH,
through the hub to a local CPU can (erroneously) conflict with
IO port operations and other transactions.

To workaound this we set a high bit in the APIC IDs used for
interrupts. This bit appears to be ignored by the sockets, but
it avoids the conflict in the hub.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
LKML-Reference: <20101116222352.GA8155@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
___

 arch/x86/include/asm/uv/uv_hub.h   |    4 ++++
 arch/x86/include/asm/uv/uv_mmrs.h  |   19 ++++++++++++++++++-
 arch/x86/kernel/apic/x2apic_uv_x.c |   25 +++++++++++++++++++++++--
 arch/x86/platform/uv/tlb_uv.c      |    2 +-
 arch/x86/platform/uv/uv_time.c     |    4 +++-
 5 files changed, 49 insertions(+), 5 deletions(-)
2010-11-18 10:41:25 +01:00
Thomas Gleixner
329b84e42e x86: Move uv to platform
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Travis <travis@sgi.com>
2010-10-27 14:30:02 +02:00