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2011-12-12ARM: stop: execute platform callback from cpu_stop codeWill Deacon
Sending IPI_CPU_STOP to a CPU causes it to execute a busy cpu_relax loop forever. This makes it impossible to kexec successfully on an SMP system since the secondary CPUs do not reset. This patch adds a callback to platform_cpu_kill, defined when CONFIG_HOTPLUG_CPU=y, from the ipi_cpu_stop handling code. This function currently just returns 1 on all platforms that define it but allows them to do something more sophisticated in the future. Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-12-06ARM: SMP: use idmap_pgd for mapping MMU enable during secondary bootingWill Deacon
The ARM SMP booting code allocates a temporary set of page tables containing an identity mapping of the kernel image and provides this to secondary CPUs for initial booting. In reality, we only need to include the __turn_mmu_on function in the identity mapping since the rest of the kernel is executing from virtual addresses after this point. This patch adds __turn_mmu_on to the .idmap.text section, allowing the SMP booting code to use the idmap_pgd directly and not have to populate its own set of page table. As a result of this patch, we can make the identity_mapping_add function static (since it is only used within mm/idmap.c) and also remove the identity_mapping_del function. The identity map population is moved to an early initcall so that it is setup in time for secondary CPU bringup. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-12-06ARM: idmap: populate identity map pgd at init time using .init.textWill Deacon
When disabling and re-enabling the MMU, it is necessary to take out an identity mapping for the code that manipulates the SCTLR in order to avoid it disappearing from under our feet. This is useful when soft rebooting and returning from CPU suspend. This patch allocates a set of page tables during boot and populates them with an identity mapping for the .idmap.text section. This means that users of the identity map do not need to manage their own pgd and can instead annotate their functions with __idmap or, in the case of assembly code, place them in the correct section. Acked-by: Dave Martin <dave.martin@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-10-28Merge branch 'devel-stable' of ↵Linus Torvalds
http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm * 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (178 commits) ARM: 7139/1: fix compilation with CONFIG_ARM_ATAG_DTB_COMPAT and large TEXT_OFFSET ARM: gic, local timers: use the request_percpu_irq() interface ARM: gic: consolidate PPI handling ARM: switch from NO_MACH_MEMORY_H to NEED_MACH_MEMORY_H ARM: mach-s5p64x0: remove mach/memory.h ARM: mach-s3c64xx: remove mach/memory.h ARM: plat-mxc: remove mach/memory.h ARM: mach-prima2: remove mach/memory.h ARM: mach-zynq: remove mach/memory.h ARM: mach-bcmring: remove mach/memory.h ARM: mach-davinci: remove mach/memory.h ARM: mach-pxa: remove mach/memory.h ARM: mach-ixp4xx: remove mach/memory.h ARM: mach-h720x: remove mach/memory.h ARM: mach-vt8500: remove mach/memory.h ARM: mach-s5pc100: remove mach/memory.h ARM: mach-tegra: remove mach/memory.h ARM: plat-tcc: remove mach/memory.h ARM: mach-mmp: remove mach/memory.h ARM: mach-cns3xxx: remove mach/memory.h ... Fix up mostly pretty trivial conflicts in: - arch/arm/Kconfig - arch/arm/include/asm/localtimer.h - arch/arm/kernel/Makefile - arch/arm/mach-shmobile/board-ap4evb.c - arch/arm/mach-u300/core.c - arch/arm/mm/dma-mapping.c - arch/arm/mm/proc-v7.S - arch/arm/plat-omap/Kconfig largely due to some CONFIG option renaming (ie CONFIG_PM_SLEEP -> CONFIG_ARM_CPU_SUSPEND for the arm-specific suspend code etc) and addition of NEED_MACH_MEMORY_H next to HAVE_IDE.
2011-10-26Merge branch 'core-locking-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) rtmutex: Add missing rcu_read_unlock() in debug_rt_mutex_print_deadlock() lockdep: Comment all warnings lib: atomic64: Change the type of local lock to raw_spinlock_t locking, lib/atomic64: Annotate atomic64_lock::lock as raw locking, x86, iommu: Annotate qi->q_lock as raw locking, x86, iommu: Annotate irq_2_ir_lock as raw locking, x86, iommu: Annotate iommu->register_lock as raw locking, dma, ipu: Annotate bank_lock as raw locking, ARM: Annotate low level hw locks as raw locking, drivers/dca: Annotate dca_lock as raw locking, powerpc: Annotate uic->lock as raw locking, x86: mce: Annotate cmci_discover_lock as raw locking, ACPI: Annotate c3_lock as raw locking, oprofile: Annotate oprofilefs lock as raw locking, video: Annotate vga console lock as raw locking, latencytop: Annotate latency_lock as raw locking, timer_stats: Annotate table_lock as raw locking, rwsem: Annotate inner lock as raw locking, semaphores: Annotate inner lock as raw locking, sched: Annotate thread_group_cputimer as raw ... Fix up conflicts in kernel/posix-cpu-timers.c manually: making cputimer->cputime a raw lock conflicted with the ABBA fix in commit bcd5cff7216f ("cputimer: Cure lock inversion").
2011-10-25Merge branch 'misc' into for-linusRussell King
Conflicts: arch/arm/mach-integrator/integrator_ap.c
2011-10-23ARM: 7133/1: SMP: fix per cpu timer setup before the cpu is marked onlineThomas Gleinxer
The problem is related to the early enabling of interrupts and the per cpu timer setup before the cpu is marked online. This doesn't need to be done in order to call calibrate_delay(). calibrate_delay() monitors jiffies, which are updated from the CPU which is waiting for the new CPU to set the online bit. So simply calibrate_delay() can be called on the new CPU just from the interrupt disabled region and move the local timer setup after stored the cpu data and before enabling interrupts. This solves both the cpu_online vs. cpu_active problem and the affinity setting of the per cpu timers. Signed-off-by: Thomas Gleinxer <tglx@linutronix.de> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-23ARM: gic, local timers: use the request_percpu_irq() interfaceMarc Zyngier
This patch remove the hardcoded link between local timers and PPIs, and convert the PPI users (TWD, MCT and MSM timers) to the new *_percpu_irq interface. Also some collateral cleanup (local_timer_ack() is gone, and the interrupt handler is strictly private to each driver). PPIs are now useable for more than just the local timers. Additional testing by David Brown (msm8250 and msm8660) and Shawn Guo (imx6q). Cc: David Brown <davidb@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Brown <davidb@codeaurora.org> Tested-by: David Brown <davidb@codeaurora.org> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2011-10-23ARM: gic: consolidate PPI handlingMarc Zyngier
PPI handling is a bit of an odd beast. It uses its own low level handling code and is hardwired to the local timers (hence lacking a registration interface). Instead, switch the low handling to the normal SPI handling code. PPIs are handled by the handle_percpu_devid_irq flow. This also allows the removal of some duplicated code. Cc: Kukjin Kim <kgene.kim@samsung.com> Cc: David Brown <davidb@codeaurora.org> Cc: Bryan Huntsman <bryanh@codeaurora.org> Cc: Tony Lindgren <tony@atomide.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Brown <davidb@codeaurora.org> Tested-by: David Brown <davidb@codeaurora.org> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2011-10-17ARM: 7115/4: move __exception and friends to asm/exception.hJamie Iles
The definition of __exception_irq_entry for CONFIG_FUNCTION_GRAPH_TRACER=y needs linux/ftrace.h, but this creates a circular dependency with it's current home in asm/system.h. Create asm/exception.h and update all current users. v4: - rebase to rmk/for-next v3: - remove redundant includes of linux/ftrace.h v2: - document the usage restricitions of __exception* Cc: Zoltan Devai <zdevai@gmail.com> Signed-off-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17ARM: 7124/1: smp: Add a localtimer handler callable from C codeShawn Guo
In order to be able to handle localtimer directly from C code instead of assembly code, introduce handle_local_timer(), which is modeled after handle_IRQ(). Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17ARM: 7123/1: smp: Add an IPI handler callable from C codeShawn Guo
In order to be able to handle IPI directly from C code instead of assembly code, introduce handle_IPI(), which is modeled after handle_IRQ(). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17ARM: 7060/1: smp: populate logical CPU mapping during bootWill Deacon
To allow booting Linux on a CPU with physical ID != 0, we need to provide a mapping from the logical CPU number to the physical CPU number. This patch adds such a mapping and populates it during boot. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17ARM: 7011/1: Add ARM cpu topology definitionVincent Guittot
The affinity between ARM processors is defined in the MPIDR register. We can identify which processors are in the same cluster, and which ones have performance interdependency. We can define the cpu topology of ARM platform, that is then used by sched_mc and sched_smt. The default state of sched_mc and sched_smt config is disable. When enabled, the behavior of the scheduler can be modified with sched_mc_power_savings and sched_smt_power_savings sysfs interfaces. Changes since v4 : * Remove unnecessary parentheses and blank lines Changes since v3 : * Update the format of printk message * Remove blank line Changes since v2 : * Update the commit message and some comments Changes since v1 : * Update the commit message * Add read_cpuid_mpidr in arch/arm/include/asm/cputype.h * Modify header of arch/arm/kernel/topology.c * Modify tests and manipulation of MPIDR's bitfields * Modify the place and dependancy of the config * Modify Noop functions Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-13locking, ARM: Annotate low level hw locks as rawThomas Gleixner
Annotate the low level hardware locks which must not be preempted. 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: Thomas Gleixner <tglx@linutronix.de> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-26atomic: use <linux/atomic.h>Arun Sharma
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-22Merge branches 'btc', 'dma', 'entry', 'fixes', 'linker-layout', 'misc', ↵Russell King
'mmci', 'suspend' and 'vfp' into for-next
2011-07-07ARM: 6993/1: platsmp: Allow secondary cpu hotplug with maxcpus=1Stephen Boyd
If an ARM system has multiple cpus in the same socket and the kernel is booted with maxcpus=1, secondary cpus are possible but not present due to how platform_smp_prepare_cpus() is called. Since most typical ARM processors don't actually support physical hotplug, initialize the present map to be equal to the possible map in generic ARM SMP code. Also, always call platform_smp_prepare_cpus() as long as max_cpus is non-zero (0 means no SMP) to allow platform code to do any SMP setup. After applying this patch it's possible to boot an ARM system with maxcpus=1 on the command line and then hotplug in secondary cpus via sysfs. This is more in line with how x86 does things. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kukjin Kim <kgene.kim@samsung.com> Cc: David Brown <davidb@codeaurora.org> Cc: Tony Lindgren <tony@atomide.com> Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Cc: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-06-21ARM: SMP: wait for CPU to be marked activeRussell King
When we bring a CPU online, we should wait for it to become active before entering the idle thread, so we know that the scheduler and thread migration is going to work. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-26ARM: 6942/1: mm: make TTBR1 always point to swapper_pg_dir on ARMv6/7Catalin Marinas
This patch makes TTBR1 point to swapper_pg_dir so that global, kernel mappings can be used exclusively on v6 and v7 cores where they are needed. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-23Merge branches 'consolidate-clksrc', 'consolidate-flash', ↵Russell King
'consolidate-generic', 'consolidate-smp', 'consolidate-stmp' and 'consolidate-zones' into consolidate
2011-05-23ARM: consolidate SMP cross call implementationRussell King
Rather than having each platform class provide a mach/smp.h header for smp_cross_call(), arrange for them to register the function with the core ARM SMP code instead. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-12Merge commit 'v2.6.39-rc7' into sched/coreIngo Molnar
2011-04-27ARM: 6887/1: Mark broadcast_timer_setup() __cpuinitStephen Boyd
This function is only called by percpu_timer_setup() which is also __cpuinit marked. Thus it's safe to mark this function as __cpuinit as well. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-04-14sched: Provide scheduler_ipi() callback in response to smp_send_reschedule()Peter Zijlstra
For future rework of try_to_wake_up() we'd like to push part of that function onto the CPU the task is actually going to run on. In order to do so we need a generic callback from the existing scheduler IPI. This patch introduces such a generic callback: scheduler_ipi() and implements it as a NOP. BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions! Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Reviewed-by: Frank Rowand <frank.rowand@am.sony.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
2011-02-23ARM: 6759/1: smp: Select local timers vs broadcast timer support runtimeSantosh Shilimkar
The current code support of dummy timers in absence of local timer is compile time. This is an attempt to convert it to runtime so that on few SOC version if the local timers aren't supported kernel can switch to dummy timers. OMAP4430 ES1.0 does suffer from this limitation. This patch should not have any functional impact on affected files. Cc: Daniel Walker <dwalker@codeaurora.org> Cc: Bryan Huntsman <bryanh@codeaurora.org> Cc: Tony Lindgren <tony@atomide.com> Cc: Kukjin Kim <kgene.kim@samsung.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: Colin Cross <ccross@android.com> Cc: Erik Gilling <konkers@android.com> Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Cc: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: David Brown <davidb@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-06Merge branch 'pgt' (early part) into develRussell King
2011-01-06Merge branch 'misc' into develRussell King
Conflicts: arch/arm/Kconfig arch/arm/common/Makefile arch/arm/kernel/Makefile arch/arm/kernel/smp.c
2011-01-05Merge branch 'clksrc' into develRussell King
Conflicts: arch/arm/mach-vexpress/v2m.c arch/arm/plat-omap/counter_32k.c arch/arm/plat-versatile/Makefile
2010-12-22ARM: pgtable: collect up identity mapping functionsRussell King
We have two places where we create identity mappings - one when we bring secondary CPUs online, and one where we setup some mappings for soft- reboot. Combine these two into a single implementation. Also collect the identity mapping deletion function. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-22ARM: pgtable: remove L2 cache flushes for SMP page table bring-upRussell King
The MMU is always configured to read page tables from the L2 cache so there's little point flushing them out of the L2 cache back to RAM. Remove these flushes. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: ensure frame pointer is reinitialized for soft-CPU hotplugRussell King
When we soft-CPU hotplug a CPU, we reset the stack pointer and jump back to start_secondary(). This allows us to restart as if the CPU was actually reset. However, we weren't resetting the frame pointer, which could cause problems with backtracing. Reset the frame pointer to zero (which means no parent frame) just like the early assembly code also does. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: split out software TLB maintainence broadcastingRussell King
smp.c is becoming too large, so split out the TLB maintainence broadcasting into a separate smp_tlb.c file. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: localtimer: clean up local timer on hot unplugRussell King
When a CPU is hot unplugged, the generic tick code cleans up the clock event device, but fails to call down to the device's set_mode function to actually shut the device down. To work around this, we've historically had a local_timer_stop() callback out of the hotplug code. However, this adds needless complexity when we have the clock event device itself available. Explicitly call the clock event device's set_mode function with CLOCK_EVT_MODE_UNUSED, so that the hardware can be cleanly shutdown without any special external callbacks. When/if the generic code is fixed, percpu_timer_stop() can be killed off. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: smp: improve CPU bringup failure diagnosticsRussell King
We used to print a bland error message which gave no clue as to the failure when we failed to bring up a secondary CPU. Resolve this by separating the two failure cases. If boot_secondary() fails, we print a message indicating the returned error code from boot_secondary(): "CPU%u: failed to boot: %d\n", cpu, ret. However, if boot_secondary() succeeded, but the CPU did not appear to mark itself online within the timeout, indicate that it failed to come online: "CPU%u: failed to come online\n", cpu Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: CPU hotplug: ensure correct ordering of unplugRussell King
Don't call idle_task_exit() with interrupts disabled, and ensure that we have a memory barrier after interrupts are disabled but before signalling that this CPU has shut down. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: CPU hotplug: move cpu_killed completion to core codeRussell King
We always need to wait for the dying CPU to reach a safe state before taking it down, irrespective of the requirements of the platform. Move the completion code into the ARM SMP hotplug code rather than having each platform re-implement this. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: consolidate trace_hardirqs_off() into common SMP codeRussell King
All platforms call trace_hardirqs_off() in their secondary startup code, so move this into the core SMP code - it doesn't need to be in the per-platform code. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: consolidate the common parts of smp_prepare_cpus()Russell King
There is a certain amount of smp_prepare_cpus() which doesn't belong in the platform support code - that is, code which is invariant to the SMP implementation. Move this code into arch/arm/kernel/smp.c, and add a platform_ prefix to the original function. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: ensure smp_send_stop() waits for CPUs to stopRussell King
Wait for CPUs to indicate that they've stopped, after sending the stop IPI, rather than blindly continuing on and hoping that they've stopped in time. Print a warning if we fail to stop the other CPUs. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: collect IPI and local timer IRQs for /proc/statRussell King
The IPI and local timer interrupts weren't being properly accounted for in /proc/stat. Collect them from the irq_stat structure, and return their sum. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: provide individual IPI interrupt statisticsRussell King
This separates out the individual IPI interrupt counts from the total IPI count, which allows better visibility of what IPIs are being used for. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: fix /proc/interrupts formattingRussell King
As per x86, align the initial column according to how many IRQs we have. Also, provide an english explaination for the 'LOC:' and 'IPI:' lines. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: move ipi_count into irq_stat structureRussell King
Move the ipi_count into irq_stat, which allows the ipi_data structure to be entirely removed. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: provide accessors for irq_stat dataRussell King
Provide __inc_irq_stat() and __get_irq_stat() to increment and read the irq stat counters. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: include local timer irq stats only when local timers configuredRussell King
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20ARM: SMP: remove send_ipi_message()Russell King
send_ipi_message() does nothing except call smp_cross_call(). As this is a static function, nothing external to this file calls it, so we can easily clean up this now unnecessary indirection. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-18ARM: smp: avoid incrementing mm_users on CPU startupRussell King
We should not be incrementing mm_users when we startup a secondary CPU - doing so results in mm_users incrementing by one each time we hotplug a CPU, which will eventually wrap, and will cause problems. Other architectures such as x86 do not increment mm_users, but only mm_count, so we follow that pattern. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-03ARM: SMP: remove IRQ-disabling for smp_cross_call()Russell King
As we've now removed the spinlock and bitmask, we have nothing left which requires interrupts to be disabled when sending an IPI. All current IPI-sending implementations use the GIC, which also does not require interrupts disabled when calling gic_raise_softirq(). Remove the now unnecessary IRQ disable. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-03ARM: SMP: avoid using bitmasks and locks for IPIs, use hardware insteadRussell King
Avoid using bitmasks and locks in the percpu area for IPIs, and instead use individual software generated interrupts to identify the reason for the IPI. This avoids the problems of having spinlocks in the percpu area. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>