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* metag: Use common outgoing-CPU-notification codePaul E. McKenney2015-03-111-3/+2
| | | | | | | | | | | | This commit removes the open-coded CPU-offline notification with new common code. This change avoids calling scheduler code using RCU from an offline CPU that RCU is ignoring. This commit is compatible with the existing code in not checking for timeout during a prior offline for a given CPU. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: <linux-metag@vger.kernel.org>
* metag/smp: Make boot_secondary() staticGeert Uytterhoeven2014-01-061-1/+1
| | | | | | | | 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>
* smp, metag: kill SMP single function call interruptJiang Liu2013-12-051-5/+1
| | | | | | | | | | | | | | | | | Commit 9a46ad6d6df3 "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>
* metag: smp: don't set irq regs in do_IPI()James Hogan2013-11-291-5/+2
| | | | | | | | | | | | Since commit f6b30d32d242 (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>
* metag: delete __cpuinit usage from all metag filesPaul Gortmaker2013-07-141-12/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* metag: smp: don't spin waiting for CPU to startJames Hogan2013-07-021-10/+6
| | | | | | | | | | | | | | | 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>
* metag: smp: enable irqs after set_cpu_onlineJames Hogan2013-07-021-5/+6
| | | | | | | | | | | | | | 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>
* metag: use clear_tasks_mm_cpumask()James Hogan2013-07-021-7/+1
| | | | | | | | | | | | | | | | | | 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>
* metag: don't check for cache aliasing on smp cpu bootJames Hogan2013-06-271-6/+0
| | | | | | | | | 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>
* Merge tag 'metag-for-v3.10-rc1' of ↵Linus Torvalds2013-04-301-0/+115
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag Pull arch/metag update from James Hogan: - Various fixes for the interrupting perf counter handling in metag's perf backend. - Add OProfile support based on perf. - Sets up cache partitions for SMP so bootloader doesn't have to. - Patch from Paul Bolle to remove ARCH_POPULATES_NODE_MAP again (touches microblaze too). - Add TLS pointer regset to metag ptrace api. - Add exported metag DSP extended context handling header <asm/ech.h>. - Increase defconfig log buffer size to 128KiB. - Various fixes, typos, missing exports. * tag 'metag-for-v3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag: metag: defconfigs: increase log buffer 8KiB => 128KiB metag: avoid unnecessary builtin dtb rebuilds metag: add exported <asm/ech.h> for extended context handling metag: export _metag_da_present and cpu_2_hwthread_id metag: ptrace: Implement NT_METAG_TLS memblock: Kill ARCH_POPULATES_NODE_MAP once more metag: cachepart: fix get_global_dcache_size() typo metag: cachepart: take into account small cache bits metag: smp: copy cache partition and enable GCOn metag: OProfile support metag: perf: prepare for use by oprofile metag: perf: don't reset TXTACTCYC metag: perf: use hard_processor_id() to get thread metag: perf: fix frequency sampling (dynamic period) metag: perf: add missing prev_count updates metag: perf: fixes for interrupting perf counters metag: perf: fix wrap handling in delta calculation metag: perf: fix core internal / perf channel mux
| * metag: smp: copy cache partition and enable GCOnJames Hogan2013-03-151-0/+115
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When starting an SMP hardware thread, copy the cache partition configuration so that the threads share the same cache partitions. Also enable the GCOn bit if running in the local half of the virtual address space to enable coherency of shared local cache partitions. An atomic unlock system event is executed by the new cpu before any memory is read to ensure that any writes made by the boot cpu prior to full coherency taking effect are visible to the new cpu. This is to allow SMP to work even when the bootloader hasn't configured the caches for coherency. A log message is printed to describe the cache partition changes so that the user is aware of potential unintentional cache wastage if they've configured the cache partitions in the wrong way. Signed-off-by: James Hogan <james.hogan@imgtec.com>
* | metag: Use generic idle loopThomas Gleixner2013-04-081-1/+1
|/ | | | | | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: James Hogan <james.hogan@imgtec.com> Link: http://lkml.kernel.org/r/20130321215234.606480852@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* metag: protect more non-MMU memory regionsJames Hogan2013-03-021-1/+1
| | | | | | | | | | | | | | Rename setup_txprivext() to setup_priv() and add initialisation of some more per-thread privilege protection registers: - TxPRIVSYSR: 0x04400000-0x047fffff 0x05000000-0x07ffffff 0x84000000-0x87ffffff - TxPIOREG: 0x02000000-0x02ffffff 0x04800000-0x048fffff - TxSYREG: 0x04000000-0x04000fff (except write fetch system event) Signed-off-by: James Hogan <james.hogan@imgtec.com>
* metag: SMP supportJames Hogan2013-03-021-0/+575
Add SMP support for metag. This allows Linux to take control of multiple hardware threads on a single Meta core, treating them as separate Linux CPUs. Signed-off-by: James Hogan <james.hogan@imgtec.com>
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