boot_secondary() is not used outside arch/metag/kernel/smp.c, hence make it
static.
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
We need to export 'cpu_core_map' since the topology_core_cpumask macro
refers to it and is used by certain kernel modules.
Found in allmodconfig build:
ERROR: "cpu_core_map" [drivers/staging/lustre/lustre/libcfs/libcfs.ko] undefined!
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Commit 9a46ad6d6d "smp: make smp_call_function_many() use logic
similar to smp_call_function_single()" has unified the way to handle
single and multiple cross-CPU function calls. Now only one interrupt is
needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.
Signed-off-by: Jiang Liu <liuj97@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <trivial@kernel.org>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Since commit f6b30d32d2 (metag: kick: add missing irq_enter/exit to
kick_handler()), the main kick_handler() function deals with setting and
restoring the irq registers pointer. Therefore do_IPI() which is called
indirectly from kick_handler() doesn't need to do that itself any
longer. Therefore remove that code and do_IPI()'s pt_regs argument.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Meta has 2 levels of page table so the pmd folds into the pud which
folds into the pgd. Therefore the !pmd check in dma_alloc_init() is dead
code since it essentially checks whether:
(init_mm->pgd + 0x770) == 0
Remove the check.
Reported-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Use __free_reserved_page() to simplify the code in arch.
It used split_page() in consistent_alloc()/__dma_alloc_coherent()/dma_alloc_coherent(),
so page->_count == 1, and we can free it safely.
__free_reserved_page()
ClearPageReserved()
init_page_count() // it won't change the value
__free_page()
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull devicetree updates from Rob Herring:
"DeviceTree updates for 3.13. This is a bit larger pull request than
usual for this cycle with lots of clean-up.
- Cross arch clean-up and consolidation of early DT scanning code.
- Clean-up and removal of arch prom.h headers. Makes arch specific
prom.h optional on all but Sparc.
- Addition of interrupts-extended property for devices connected to
multiple interrupt controllers.
- Refactoring of DT interrupt parsing code in preparation for
deferred probe of interrupts.
- ARM cpu and cpu topology bindings documentation.
- Various DT vendor binding documentation updates"
* tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (82 commits)
powerpc: add missing explicit OF includes for ppc
dt/irq: add empty of_irq_count for !OF_IRQ
dt: disable self-tests for !OF_IRQ
of: irq: Fix interrupt-map entry matching
MIPS: Netlogic: replace early_init_devtree() call
of: Add Panasonic Corporation vendor prefix
of: Add Chunghwa Picture Tubes Ltd. vendor prefix
of: Add AU Optronics Corporation vendor prefix
of/irq: Fix potential buffer overflow
of/irq: Fix bug in interrupt parsing refactor.
of: set dma_mask to point to coherent_dma_mask
of: add vendor prefix for PHYTEC Messtechnik GmbH
DT: sort vendor-prefixes.txt
of: Add vendor prefix for Cadence
of: Add empty for_each_available_child_of_node() macro definition
arm/versatile: Fix versatile irq specifications.
of/irq: create interrupts-extended property
microblaze/pci: Drop PowerPC-ism from irq parsing
of/irq: Create of_irq_parse_and_map_pci() to consolidate arch code.
of/irq: Use irq_of_parse_and_map()
...
Pull metag architecture changes from James Hogan:
- A change to remove the last dependence on bootloader exception
handlers so that QEMU can more easily boot an SMP Linux/Meta kernel
image directly.
- A fix for a minor off by one error in a BUG_ON condition found by Dan
Carpenter.
* tag 'metag-for-v3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
metag: off by one in setup_bootmem_node()
metag: handle low level kicks directly
Kick interrupts trigger the LWK (low level kick) signal, usually handled
by the __TBIDoStdLWK() function which is the only handler inherited from
the bootloader. The LWK signal is converted either to a SWK (plain
software kick) or a SWS (software kick with an attached message).
Linux has kick_handler() to handle SWK and call registered kick handlers
(IPIs and inter-thread comms), but SWS is as far as I'm aware unused
with Linux.
Therefore remove that abstraction and have Linux handle LWK directly.
This will reduce kick latency slightly, and reduce our dependence on the
bootloader, which makes it easier to directly boot a kernel in QEMU
(particularly for SMP).
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Convert metag to use the common of_flat_dt_get_machine_name function.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
[james.hogan: fix missing arch_get_next_mach and const mismatch]
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Use the common unflatten_and_copy_device_tree to copy the built-in FDT
out of init section.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: James Hogan <james.hogan@imgtec.com>
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings. In any case, they are temporary and harmless.
This removes all the arch/metag uses of the __cpuinit macros from
all C files. Currently metag does not have any __CPUINIT used in
assembly files.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: James Hogan <james.hogan@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Pull Metag architecture changes from James Hogan:
- Infrastructure and DT files for TZ1090 SoC (pin control drivers
already merged via pinctrl tree).
- Panic on boot instead of just warning if cache aliasing possible.
- Various SMP/hotplug fixes.
- Various other randconfig/sparse fixes.
* tag 'metag-for-v3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag: (24 commits)
metag: move EXPORT_SYMBOL(csum_partial) to metag_ksyms.c
metag: cpu hotplug: route_irq: preserve irq mask
metag: kick: add missing irq_enter/exit to kick_handler()
metag: smp: don't spin waiting for CPU to start
metag: smp: enable irqs after set_cpu_online
metag: use clear_tasks_mm_cpumask()
metag: tz1090: select and instantiate pinctrl-tz1090-pdc
metag: tz1090: select and instantiate pinctrl-tz1090
metag: don't check for cache aliasing on smp cpu boot
metag: panic if cache aliasing possible
metag: *.dts: include using preprocessor
metag: add <dt-bindings/> symlink
metag/.gitignore: Extend the *.dtb pattern to match the dtb.S files
metag/traps: include setup.h for the per_cpu_trap_init declaration
metag/traps: Mark die() as __noreturn to match the declaration.
metag/processor.h: Add missing cpuinfo_op declaration.
metag/setup: Restrict scope for the capabilities variable
metag/mm/cache: Restrict scope for metag_lnkget_probe
metag/asm/irq.h: Declare init_IRQ
metag/kernel/irq.c: Declare root_domain as static
...
Move EXPORT_SYMBOL(csum_partial) from lib/checksum.c into metag_ksyms.c
so that it doesn't get omitted by the static linker if it's not used by
any other statically linked code, which can result in undefined symbols
when building modules.
For example a randconfig caused the following error:
ERROR: "csum_partial" [fs/reiserfs/reiserfs.ko] undefined!
Signed-off-by: James Hogan <james.hogan@imgtec.com>
The route_irq() function needs to preserve the irq mask by using the
_irqsave/irqrestore variants of raw spin lock functions instead of the
_irq variants. This is because it is called from __cpu_disable() (via
migrate_irqs()), which is called with IRQs disabled, so using the _irq
variants re-enables IRQs.
This appears to have been causing occasional hits of the
BUG_ON(!irqs_disabled()) in __irq_work_run() during CPU hotplug soak
testing:
BUG: failure at kernel/irq_work.c:122/__irq_work_run()!
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
kick_handler() doesn't have an irq_enter/exit pair, but it's used for
handling SMP IPIs which require work to be done in softirqs, which are
invoked from irq_exit() when the hard irq nest count reaches 0.
The scheduler_ipi() callback in the IPI handler calls irq_enter/exit
itself, but this is inside kick_handler()'s spin lock critical section,
so if an invoked softirq issues an IPI the kick_handler() will be
re-entered on the same CPU and will deadlock.
This is easily fixed by adding the missing irq_enter/exit to
kick_handler() so that the hard irq nest count doesn't reach 0 until
after the spin lock has been released.
Ideally the spin lock protected handler list will also be replaced by a
lockless RCU protected list since it is certainly mostly read. That can
be done in a later change though.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Use a completion to block until a secondary CPU has started up, like ARM
do, instead of a loop of udelays.
On Meta, SMP is really SMT, with each "CPU" being a different hardware
thread on the same Meta processor core, so as well as being more
efficient and latency friendly, using a completion prevents the bogomips
of the secondary CPU from being drastically skewed every time by the
execution of the tight in-cache udelay loop on the other CPU.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
In secondary_start_kernel() interrupts should be enabled with
local_irq_enable() after the cpu is marked as online with
set_cpu_online(). Otherwise it's possible for a timer interrupt to
trigger a softirq, which if the cpu is marked as offline may have it's
affinity altered.
Reported-by: Kirill Tkhai <tkhai@yandex.ru>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Checking for process->mm is not enough because process' main thread may
exit or detach its mm via use_mm(), but other threads may still have a
valid mm.
To fix this we would need to use find_lock_task_mm(), which would walk
up all threads and returns an appropriate task (with task lock held).
clear_tasks_mm_cpumask() was introduced in v3.5-rc1 to fix this issue,
so let's use it for metag too.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>
The cache configuration of the boot cpu is now duplicated to secondary
cpus, so there's no need to check for cache aliasing again when a
secondary cpu is booted. Therefore remove the check from
secondary_start_kernel().
Signed-off-by: James Hogan <james.hogan@imgtec.com>
If the cache and page size configuration allows for cache aliasing to
occur we warn on boot, but the log messages are easy to miss and will
result is random crashes occuring in userland. Let's panic too in this
case so that the user immediately knows they need to fix the cache
configuration or configured page size.
Also fix the warning messages which display the cache and page sizes to
include newlines, and add the word "Potential" since an actual cache
alias hasn't been detected.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
