linux-toradex.git/arch/ia64/sn, branch v4.2.7

ia64: don't use module_init for non-modular core kernel/mca.c code

2015-06-16T18:12:30+00:00

The mca.c code is always built in.  It will never be modular,
so using module_init as an alias for __initcall is rather
misleading.

Fix this up now, so that we can relocate module_init from
init.h into module.h in the future.  If we don't do this, we'd
have to add module.h to obviously non-modular code, and that
would be a worse thing.

Direct use of __initcall is discouraged, vs prioritized ones.
Use of device_initcall is consistent with what __initcall
maps onto, and hence does not change the init order, making the
impact of this change zero.   Should someone with real hardware
for boot testing want to change it later to arch_initcall or
something different, they can do that at a later date.

Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: linux-ia64@vger.kernel.org
Signed-off-by: Paul Gortmaker

PCI: Assign resources before drivers claim devices (pci_scan_root_bus())

2015-03-19T15:17:13+00:00

Previously, pci_scan_root_bus() created a root PCI bus, enumerated the
devices on it, and called pci_bus_add_devices(), which made the devices
available for drivers to claim them.

Most callers assigned resources to devices after pci_scan_root_bus()
returns, which may be after drivers have claimed the devices.  This is
incorrect; the PCI core should not change device resources while a driver
is managing the device.

Remove pci_bus_add_devices() from pci_scan_root_bus() and do it after any
resource assignment in the callers.

Note that ARM's pci_common_init_dev() already called pci_bus_add_devices()
after pci_scan_root_bus(), so we only need to remove the first call:

  pci_common_init_dev
    pcibios_init_hw
      pci_scan_root_bus
        pci_bus_add_devices        # first call
    pci_bus_assign_resources
    pci_bus_add_devices            # second call

[bhelgaas: changelog, drop "root_bus" var in alpha common_init_pci(),
return failure earlier in mn10300, add "return" in x86 pcibios_scan_root(),
return early if xtensa platform_pcibios_fixup() fails]
Signed-off-by: Yijing Wang 
Signed-off-by: Bjorn Helgaas 
CC: Richard Henderson 
CC: Ivan Kokshaysky 
CC: Matt Turner 
CC: David Howells 
CC: Tony Luck 
CC: Michal Simek 
CC: Ralf Baechle 
CC: Koichi Yasutake 
CC: Sebastian Ott 
CC: "David S. Miller" 
CC: Chris Metcalf 
CC: Chris Zankel 
CC: Max Filippov 
CC: Thomas Gleixner

PCI/MSI: Rename mask/unmask_msi_irq treewide

2014-11-23T12:01:45+00:00

The PCI/MSI irq chip callbacks mask/unmask_msi_irq have been renamed
to pci_msi_mask/unmask_irq to mark them PCI specific. Rename all usage
sites. The conversion helper functions are kept around to avoid
conflicts in next and will be removed after merging into mainline.

Coccinelle assisted conversion. No functional change.

Signed-off-by: Thomas Gleixner 
Cc: Bjorn Helgaas 
Cc: Russell King 
Cc: Ralf Baechle 
Cc: Benjamin Herrenschmidt 
Cc: Heiko Carstens 
Cc: "David S. Miller" 
Cc: Chris Metcalf 
Cc: x86@kernel.org
Cc: Jiang Liu 
Cc: Jason Cooper 
Cc: Murali Karicheri 
Cc: Thierry Reding 
Cc: Mohit Kumar 
Cc: Simon Horman 
Cc: Michal Simek 
Cc: Yijing Wang

PCI/MSI: Rename write_msi_msg() to pci_write_msi_msg()

2014-11-23T12:01:45+00:00

Rename write_msi_msg() to pci_write_msi_msg() to mark it as PCI
specific.

Signed-off-by: Jiang Liu 
Cc: Bjorn Helgaas 
Cc: Grant Likely 
Cc: Marc Zyngier 
Cc: Yingjoe Chen 
Cc: Yijing Wang 
Signed-off-by: Thomas Gleixner

Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

2014-10-15T05:48:18+00:00

Pull percpu consistent-ops changes from Tejun Heo:
"Way back, before the current percpu allocator was implemented, static
and dynamic percpu memory areas were allocated and handled separately
and had their own accessors. The distinction has been gone for many
years now; however, the now duplicate two sets of accessors remained
with the pointer based ones - this_cpu_*() - evolving various other
operations over time. During the process, we also accumulated other
inconsistent operations.

This pull request contains Christoph's patches to clean up the
duplicate accessor situation. __get_cpu_var() uses are replaced with
with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

Unfortunately, the former sometimes is tricky thanks to C being a bit
messy with the distinction between lvalues and pointers, which led to
a rather ugly solution for cpumask_var_t involving the introduction of
this_cpu_cpumask_var_ptr().

This converts most of the uses but not all. Christoph will follow up
with the remaining conversions in this merge window and hopefully
remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
irqchip: Properly fetch the per cpu offset
percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
Revert "powerpc: Replace __get_cpu_var uses"
percpu: Remove __this_cpu_ptr
clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
sparc: Replace __get_cpu_var uses
avr32: Replace __get_cpu_var with __this_cpu_write
blackfin: Replace __get_cpu_var uses
tile: Use this_cpu_ptr() for hardware counters
tile: Replace __get_cpu_var uses
powerpc: Replace __get_cpu_var uses
alpha: Replace __get_cpu_var
ia64: Replace __get_cpu_var uses
s390: cio driver &__get_cpu_var replacements
s390: Replace __get_cpu_var uses
mips: Replace __get_cpu_var uses
MIPS: Replace __get_cpu_var uses in FPU emulator.
arm: Replace __this_cpu_ptr with raw_cpu_ptr
...

PCI/MSI: Use __get_cached_msi_msg() instead of get_cached_msi_msg()

2014-10-01T18:21:23+00:00

Both callers of get_cached_msi_msg() start with a struct irq_data pointer,
look up the corresponding IRQ number, and pass it to get_cached_msi_msg(),
which then uses irq_get_irq_data() to look up the struct irq_data again to
call __get_cached_msi_msg().

Since we already have the struct irq_data, call __get_cached_msi_msg()
directly and skip the lookup work done by get_cached_msi_msg().

No functional change.

[bhelgaas: changelog]
Signed-off-by: Yijing Wang 
Signed-off-by: Bjorn Helgaas 
CC: Tony Luck 
CC: linux-ia64@vger.kernel.org

ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.

2014-09-02T15:52:36+00:00

There must be an explit statement to modify the percpu variable after
the conversion of the sn_nodpda macro to use this_cpu_read.

Signed-off-by: Christoph Lameter 
Signed-off-by: Tejun Heo 
Compile-tested-by: Guenter Roeck

ia64: Replace __get_cpu_var uses

2014-08-26T17:45:52+00:00

__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.

At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.

The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e.  using a global
register that may be set to the per cpu base.

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: Tony Luck 
Cc: Fenghua Yu 
Cc: linux-ia64@vger.kernel.org
Signed-off-by: Christoph Lameter 
Signed-off-by: Tejun Heo

[IA64] sn: Do not needlessly convert between pointers and integers

2014-07-29T23:28:15+00:00

The nasid_to_try variable is an array of integers, so plain integers can
be used when assigning values to the elements rather than casting a NULL
pointer to an integer, which results in the following warning from GCC:

	arch/ia64/sn/kernel/bte.c:117:22: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
	    nasid_to_try[1] = (int)NULL;
	                      ^
	arch/ia64/sn/kernel/bte.c:125:22: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
	    nasid_to_try[1] = (int)NULL;
	                      ^

Replace (int)NULL with a simple 0 to silence these warnings.

Signed-off-by: Thierry Reding 
Signed-off-by: Tony Luck

[IA64] sn: Fix zeroing of PDAs

2014-07-29T23:26:37+00:00

The code uses a the following to zero out a PDA:

	memset(pda, 0, sizeof(pda));

But sizeof(pda) will return the size of a pointer rather than the size
of the structure pointed to. This triggers the following warning from
GCC:

	arch/ia64/sn/kernel/setup.c:582:23: warning: argument to 'sizeof' in 'memset' call is the same pointer type 'struct pda_s *' as the destination; expected 'struct pda_s' or an explicit length [-Wsizeof-pointer-memaccess]
	  memset(pda, 0, sizeof(pda));
	                       ^

Fix this by passing in the size of the structure using sizeof(*pda)
instead.

Signed-off-by: Thierry Reding 
Signed-off-by: Tony Luck