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
...
It would make more sense to pass char __user * instead of
char * in callers of do_mount() and do getname() inside do_mount().
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Seunghun Lee <waydi1@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
__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: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Acked-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
We don't need anything arch-specific in pcibios_enable_device(), so drop
the arch implementation and use the default generic one.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: linux-alpha@vger.kernel.org
* pci/resource:
PCI: Allocate 64-bit BARs above 4G when possible
PCI: Enforce bus address limits in resource allocation
PCI: Split out bridge window override of minimum allocation address
agp/ati: Use PCI_COMMAND instead of hard-coded 4
agp/intel: Use CPU physical address, not bus address, for ioremap()
agp/intel: Use pci_bus_address() to get GTTADR bus address
agp/intel: Use pci_bus_address() to get MMADR bus address
agp/intel: Support 64-bit GMADR
agp/intel: Rename gtt_bus_addr to gtt_phys_addr
drm/i915: Rename gtt_bus_addr to gtt_phys_addr
agp: Use pci_resource_start() to get CPU physical address for BAR
agp: Support 64-bit APBASE
PCI: Add pci_bus_address() to get bus address of a BAR
PCI: Convert pcibios_resource_to_bus() to take a pci_bus, not a pci_dev
PCI: Change pci_bus_region addresses to dma_addr_t
These interfaces:
pcibios_resource_to_bus(struct pci_dev *dev, *bus_region, *resource)
pcibios_bus_to_resource(struct pci_dev *dev, *resource, *bus_region)
took a pci_dev, but they really depend only on the pci_bus. And we want to
use them in resource allocation paths where we have the bus but not a
device, so this patch converts them to take the pci_bus instead of the
pci_dev:
pcibios_resource_to_bus(struct pci_bus *bus, *bus_region, *resource)
pcibios_bus_to_resource(struct pci_bus *bus, *resource, *bus_region)
In fact, with standard PCI-PCI bridges, they only depend on the host
bridge, because that's the only place address translation occurs, but
we aren't going that far yet.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Vince's perf fuzzer uncovered the following issue on Alpha:
Unable to handle kernel paging request at virtual address fffffbfe4e46a0e8
CPU 0 perf_fuzzer(1278): Oops 0
pc = [<fffffc000031fbc0>] ra = [<fffffc000031ff54>] ps = 0007 Not tainted
pc is at alpha_perf_event_set_period+0x60/0xf0
ra is at alpha_pmu_enable+0x1a4/0x1c0
v0 = 0000000000000000 t0 = 00000000000fffff t1 = fffffc007b3f5800
t2 = fffffbff275faa94 t3 = ffffffffc9b9bd89 t4 = fffffbfe4e46a098
t5 = 0000000000000020 t6 = fffffbfe4e46a0b8 t7 = fffffc007f4c8000
s0 = 0000000000000000 s1 = fffffc0001b0c018 s2 = fffffc0001b0c020
s3 = fffffc007b3f5800 s4 = 0000000000000001 s5 = ffffffffc9b9bd85
s6 = 0000000000000001
a0 = 0000000000000006 a1 = fffffc007b3f5908 a2 = fffffbfe4e46a098
a3 = 00000005000108c0 a4 = 0000000000000000 a5 = 0000000000000000
t8 = 0000000000000001 t9 = 0000000000000001 t10= 0000000027829f6f
t11= 0000000000000020 pv = fffffc000031fb60 at = fffffc0000950900
gp = fffffc0000940900 sp = fffffc007f4cbca8
Disabling lock debugging due to kernel taint
Trace:
[<fffffc000031ff54>] alpha_pmu_enable+0x1a4/0x1c0
[<fffffc000039f4e8>] perf_pmu_enable+0x48/0x60
[<fffffc00003a0d6c>] __perf_install_in_context+0x15c/0x230
[<fffffc000039d1f0>] remote_function+0x80/0xa0
[<fffffc00003a0c10>] __perf_install_in_context+0x0/0x230
[<fffffc000037b7e4>] smp_call_function_single+0x1b4/0x1d0
[<fffffc000039bb70>] task_function_call+0x60/0x80
[<fffffc00003a0c10>] __perf_install_in_context+0x0/0x230
[<fffffc000039bb44>] task_function_call+0x34/0x80
[<fffffc000039d3fc>] perf_install_in_context+0x9c/0x150
[<fffffc00003a0c10>] __perf_install_in_context+0x0/0x230
[<fffffc00003a5100>] SYSC_perf_event_open+0x360/0xac0
[<fffffc00003110c4>] entSys+0xa4/0xc0
This is due to the raw event encoding being used as an index directly
into the ev67_mapping array, rather than being validated against the
ev67_pmc_event_type enumeration instead. Unlike other architectures,
which allow raw events to propagate into the hardware counters with
little interference, the limited number of events on Alpha and the
strict event <-> counter relationships mean that raw events actually
correspond to the Linux-specific Alpha events, rather than anything
defined by the architecture.
This patch adds a new callback to alpha_pmu_t for validating the raw
event encoding with the Linux event types for the PMU, preventing the
out-of-bounds array access.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Michael Cree <mcree@orcon.net.nz>
Acked-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
QEMU provides a high-resolution timer and alarm; use this for
a clock source and clock event source when available.
Signed-off-by: Richard Henderson <rth@twiddle.net>
This allows us to get rid of some hacky code for SMP. Get rid of
some cycle counter hackery that's now handled by generic code via
clocksource + clock_event_device objects.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Don't depend on SMP, just check the number of processors online.
This allows a single distribution kernel to use the clocksource
when run on a single processor machine. Do depend on whether or
not we're using WTINT.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Discontinue use of GENERIC_CMOS_UPDATE; rely on the RTC subsystem.
The marvel platform requires that the rtc only be touched from the
boot cpu. This had been partially implemented with hooks for
get/set_rtc_time, but read/update_persistent_clock were not handled.
Move the hooks from the machine_vec to a special rtc_class_ops struct.
We had read_persistent_clock managing the epoch against which the
rtc hw is based, but this didn't apply to get_rtc_time or set_rtc_time.
This resulted in incorrect values when hwclock(8) gets involved.
Allow the epoch to be set from the kernel command-line, overriding
the autodetection, which is doomed to fail in 2020. Further, by
implementing the rtc ioctl function, we can expose this epoch to
userland.
Elide the alarm functions that RTC_DRV_CMOS implements. This was
highly questionable on Alpha, since the interrupt is used by the
system timer.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Use WTINT to wait for the next interrupt. Squash the WTINT call
if the PALcode doesn't support it (e.g. MILO). No attempt is yet
made to skip clock ticks during normal scheduling in order to stay
in power down mode longer.
Signed-off-by: Richard Henderson <rth@twiddle.net>
When building a generic kernel, do a run-time check on the serial
number, like we do for MILO. When building a custom kernel, make
this a configure-time check.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Compiling with GCC 4.8 yields several instances of
crypto/vmac.c: In function ‘vmac_final’:
crypto/vmac.c:616:9: warning: value computed is not used [-Wunused-value]
memset(&mac, 0, sizeof(vmac_t));
^
arch/alpha/include/asm/string.h:31:25: note: in definition of macro ‘memset’
? __builtin_memset((s),0,(n)) \
^
Converting the macro to an inline function eliminates this problem.
However, doing only that causes problems with the GCC 3.x series. The
inline function cannot be named "memset", as otherwise we wind up with
recursion via __builtin_memset. Solve this by adjusting the symbols
such that __memset is the inline, and ___memset is the real function.
Signed-off-by: Richard Henderson <rth@twiddle.net>
The code as written is correct, and will be used by QEMU emulation.
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Having unwind info past the PALcode generated stack frame makes
debugging the kernel significantly easier.
Acked-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
For sending message:
*(unsigned int *)&cpu->ipc_buffer[0] = len;
cp1 = (char *) &cpu->ipc_buffer[1];
But for receive message:
cnt = cpu->ipc_buffer[0] >> 32;
...
cp1 = (char *) &cpu->ipc_buffer[11];
They are not pairs, it is typo issue of the redundency '1'.
So need use '1' instead of '11'.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Chen Gang <gang.chen@asianux.com>
