- 03 7月, 2012 1 次提交
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由 Yong Zhang 提交于
1) call_function.lock used in smp_call_function_many() is just to protect call_function.queue and &data->refs, cpu_online_mask is outside of the lock. And it's not necessary to protect cpu_online_mask, because data->cpumask is pre-calculate and even if a cpu is brougt up when calling arch_send_call_function_ipi_mask(), it's harmless because validation test in generic_smp_call_function_interrupt() will take care of it. 2) For cpu down issue, stop_machine() will guarantee that no concurrent smp_call_fuction() is processing. Signed-off-by: NYong Zhang <yong.zhang0@gmail.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 26 4月, 2012 2 次提交
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由 Thomas Gleixner 提交于
Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Link: http://lkml.kernel.org/r/20120420124557.311212868@linutronix.de
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由 Thomas Gleixner 提交于
Preparatory patch to make the idle thread allocation for secondary cpus generic. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Howells <dhowells@redhat.com> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: David S. Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Richard Weinberger <richard@nod.at> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de
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- 29 3月, 2012 1 次提交
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由 David Howells 提交于
Disintegrate asm/system.h for PowerPC. Signed-off-by: NDavid Howells <dhowells@redhat.com> Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org> cc: linuxppc-dev@lists.ozlabs.org
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- 22 12月, 2011 1 次提交
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由 Kay Sievers 提交于
This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem and converts the devices to regular devices. The sysdev drivers are implemented as subsystem interfaces now. After all sysdev classes are ported to regular driver core entities, the sysdev implementation will be entirely removed from the kernel. Userspace relies on events and generic sysfs subsystem infrastructure from sysdev devices, which are made available with this conversion. Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@amd64.org> Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk> Cc: Len Brown <lenb@kernel.org> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: NKay Sievers <kay.sievers@vrfy.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
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- 25 11月, 2011 1 次提交
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由 Thomas Gleixner 提交于
IPI handlers cannot be threaded. Remove the obsolete IRQF_DISABLED flag (see commit e58aa3d2) while at it. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 08 11月, 2011 1 次提交
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由 Yong Zhang 提交于
Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled], We run all interrupt handlers with interrupts disabled and we even check and yell when an interrupt handler returns with interrupts enabled (see commit [b738a50a: genirq: Warn when handler enables interrupts]). So now this flag is a NOOP and can be removed. Signed-off-by: NYong Zhang <yong.zhang0@gmail.com> Acked-by: NArnd Bergmann <arnd@arndb.de> Acked-by: NGeoff Levand <geoff@infradead.org> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 01 11月, 2011 1 次提交
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由 Paul Gortmaker 提交于
All these files were including module.h just for the basic EXPORT_SYMBOL infrastructure. We can shift them off to the export.h header which is a way smaller footprint and thus realize some compile time gains. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
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- 20 9月, 2011 1 次提交
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由 Benjamin Herrenschmidt 提交于
This adds more generic support for doing CPU hotplug with a simple idle loop and no actual reset of the processors. The generic smp_generic_kick_cpu() does the hotplug bringup trick if the PACA shows that the CPU has already been started at boot and we provide an accessor for the CPU state. Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 27 7月, 2011 1 次提交
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由 Arun Sharma 提交于
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: NArun Sharma <asharma@fb.com> Reviewed-by: NEric 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: NMike Frysinger <vapier@gentoo.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 12 7月, 2011 1 次提交
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由 Paul Mackerras 提交于
This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: NPaul Mackerras <paulus@samba.org> Signed-off-by: NAlexander Graf <agraf@suse.de>
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- 08 7月, 2011 1 次提交
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由 Becky Bruce 提交于
This is used to round-robin TLBCAM entries. Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org> Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
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- 29 6月, 2011 1 次提交
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由 Scott Wood 提交于
Signed-off-by: NScott Wood <scottwood@freescale.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 20 6月, 2011 1 次提交
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由 Paul Mackerras 提交于
On many platforms (including pSeries), smp_ops->message_pass is always smp_muxed_ipi_message_pass. This changes arch/powerpc/kernel/smp.c so that if smp_ops->message_pass is NULL, it calls smp_muxed_ipi_message_pass directly. This means that a platform doesn't need to set both .message_pass and .cause_ipi, only one of them. It is a slight performance improvement in that it gets rid of an indirect function call at the expense of a predictable conditional branch. Signed-off-by: NPaul Mackerras <paulus@samba.org> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 26 5月, 2011 1 次提交
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由 Milton Miller 提交于
The cell iic interrupt controller has enough software caused interrupts to use a unique interrupt for each of the 4 messages powerpc uses. This means each interrupt gets its own irq action/data combination. Use the seperate, optimized, arch common ipi action functions registered via the helper smp_request_message_ipi instead passing the message as action data to a single action that then demultipexes to the required acton via a switch statement. smp_request_message_ipi will register the action as IRQF_PER_CPU and IRQF_DISABLED, and WARN if the allocation fails for some reason, so no need to print on that failure. It will return positive if the message will not be used by the kernel, in which case we can free the virq. In addition to elimiating inefficient code, this also corrects the error that a kernel built with kexec but without a debugger would not register the ipi for kdump to notify the other cpus of a crash. This also restores the debugger action to be static to kernel/smp.c. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 19 5月, 2011 5 次提交
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由 Milton Miller 提交于
Since there are only 4 messages, we can replace the atomic bit set (which uses atomic load reserve and store conditional sequence) with a byte stores to seperate bytes. We still have to perform a load reserve and store conditional sequence to avoid loosing messages on reception but we can do that with a single call to xchg. The do {} while and __BIG_ENDIAN specific mask testing was chosen by looking at the generated asm code. On gcc-4.4, the bit masking becomes a simple bit mask and test of the register returned from xchg without storing and loading the value to the stack like attempts with a union of bytes and an int (or worse, loading single bit constants from the constant pool into non-voliatle registers that had to be preseved on the stack). The do {} while avoids an unconditional branch to the end of the loop to test the entry / repeat condition of a while loop and instead optimises for the expected single iteration of the loop. We have a full mb() at the beginning to cover ordering between send, ipi, and receive so we can use xchg_local and forgo the further acquire and release barriers of xchg. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Milton Miller 提交于
Compile the new smp ipi mux and demux code only if a platform will make use of it. The new config is selected as required. The new cause_ipi smp op is only available conditionally to point out configs where the select is required; this makes setting the op an immediate fail instead of a deferred unresolved symbol at link. This also creates a new config for power surge powermac upgrade support that can be disabled in expert mode but is default on. I also removed the depends / default y on CONFIG_XICS since it is selected by PSERIES. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Milton Miller 提交于
Consolidate the mux and demux of ipi messages into smp.c and call a new smp_ops callback to actually trigger the ipi. The powerpc architecture code is optimised for having 4 distinct ipi triggers, which are mapped to 4 distinct messages (ipi many, ipi single, scheduler ipi, and enter debugger). However, several interrupt controllers only provide a single software triggered interrupt that can be delivered to each cpu. To resolve this limitation, each smp_ops implementation created a per-cpu variable that is manipulated with atomic bitops. Since these lines will be contended they are optimialy marked as shared_aligned and take a full cache line for each cpu. Distro kernels may have 2 or 3 of these in their config, each taking per-cpu space even though at most one will be in use. This consolidation removes smp_message_recv and replaces the single call actions cases with direct calls from the common message recognition loop. The complicated debugger ipi case with its muxed crash handling code is moved to debug_ipi_action which is now called from the demux code (instead of the multi-message action calling smp_message_recv). I put a call to reschedule_action to increase the likelyhood of correctly merging the anticipated scheduler_ipi() hook coming from the scheduler tree; that single required call can be inlined later. The actual message decode is a copy of the old pseries xics code with its memory barriers and cache line spacing, augmented with a per-cpu unsigned long based on the book-e doorbell code. The optional data is set via a callback from the implementation and is passed to the new cause-ipi hook along with the logical cpu number. While currently only the doorbell implemntation uses this data it should be almost zero cost to retrieve and pass it -- it adds a single register load for the argument from the same cache line to which we just completed a store and the register is dead on return from the call. I extended the data element from unsigned int to unsigned long in case some other code wanted to associate a pointer. The doorbell check_self is replaced by a call to smp_muxed_ipi_resend, conditioned on the CPU_DBELL feature. The ifdef guard could be relaxed to CONFIG_SMP but I left it with BOOKE for now. Also, the doorbell interrupt vector for book-e was not calling irq_enter and irq_exit, which throws off cpu accounting and causes code to not realize it is running in interrupt context. Add the missing calls. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Milton Miller 提交于
The only user of MSG_ALL_BUT_SELF in the whole kernel tree is powerpc, and it only uses it to start the debugger. Both debuggers always call smp_send_debugger_break with MSG_ALL_BUT_SELF, and only mpic can do anything more optimal than a loop over all online cpus, but all message passing implementations have to code for this special delivery target. Convert smp_send_debugger_break to take void and loop calling the smp_ops message_pass function for each of the other cpus in the online cpumask. Use raw_smp_processor_id() because we are either entering the debugger or trying to start kdump and the additional warning it not useful were it to trigger. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 kerstin jonsson 提交于
commit c56e5853 breaks SMP support in PPC_47x chip. secondary_ti must be set to current thread info before callin kick_cpu or else start_secondary_47x will jump into void when trying to return to c-code. In the current setup secondary_ti is initialized before the CPU idle task is started and only the boot core will start. I am not sure this is the correct solution, but it makes SMP possible in my chip. Note! The HOTPLUG support probably need some fixing to, There is no trampoline code available in head_44x.S - start_secondary_resume? Signed-off-by: NKerstin Jonsson <kerstin.jonsson@ericsson.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 04 5月, 2011 1 次提交
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由 KOSAKI Motohiro 提交于
Adapt new API. Almost change is trivial. Most important change is the below line because we plan to change task->cpus_allowed implementation. - ctx->cpus_allowed = current->cpus_allowed; Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 20 4月, 2011 1 次提交
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由 Michael Ellerman 提交于
When we start a cpu we use smp_ops->kick_cpu(), which currently returns void, it should be able to fail. Convert it to return int, and update all uses. Convert all the current error cases to return -ENOENT, which is what would eventually be returned by __cpu_up() currently when it doesn't detect the cpu as coming up in time. Signed-off-by: NMichael Ellerman <michael@ellerman.id.au> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 14 4月, 2011 1 次提交
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由 Peter Zijlstra 提交于
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: NRussell King <rmk+kernel@arm.linux.org.uk> Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: NChris Metcalf <cmetcalf@tilera.com> Acked-by: NJesper Nilsson <jesper.nilsson@axis.com> Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NRalf Baechle <ralf@linux-mips.org> Reviewed-by: NFrank 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: NIngo Molnar <mingo@elte.hu> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
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- 01 4月, 2011 9 次提交
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由 Benjamin Herrenschmidt 提交于
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Benjamin Herrenschmidt 提交于
Instead of creating idle threads at boot for all possible CPUs, we create them on demand, like x86 or ARM, and we properly call init_idle to re-initialize an idle thread when a CPU was unplugged and is now re-plugged. Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Benjamin Herrenschmidt 提交于
Instead, keep it static, expose an accessor and use that from the PowerMac code. Avoids easy namespace collisions and will make it easier to consolidate with other implementations. Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Benjamin Herrenschmidt 提交于
This allows us to stop abusing smp_ops->setup_cpu() for cleanup tasks that have to take place after the initial boot time CPU bringup. Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Benjamin Herrenschmidt 提交于
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Benjamin Herrenschmidt 提交于
Remove the last remnants of cpu_enable(), everybody uses the normal __cpu_up() path now Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Benjamin Herrenschmidt 提交于
Nobody uses it, besides we should always use the normal __cpu_up path anyways Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Benjamin Herrenschmidt 提交于
This is used by some "soft" hotplug implementations. I needs to call idle_task_exit() when the CPU is going away, and we remove the now no-longer needed set_cpu_online() and local_irq_enable() which are handled by the return to start_secondary Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Benjamin Herrenschmidt 提交于
Various thing are torn down when a CPU is hot-unplugged. That CPU is expected to go back to start_secondary when re-plugged to re initialize everything, such as clock sources, maps, ... Some implementations just return from cpu_die() callback in the idle loop when the CPU is "re-plugged". This is not enough. We fix it using a little asm trampoline which resets the stack and calls back into start_secondary as if we were all fresh from boot. The trampoline already existed on ppc64, but we add it for ppc32 Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 29 11月, 2010 1 次提交
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由 Vaidyanathan Srinivasan 提交于
These APIs take logical cpu number as input Change cpu_first_thread_in_core() to cpu_first_thread_sibling() Change cpu_last_thread_in_core() to cpu_last_thread_sibling() These APIs convert core number (index) to logical cpu/thread numbers Add cpu_first_thread_of_core(int core) Changed cpu_thread_to_core() to cpu_core_index_of_thread(int cpu) The goal is to make 'threads_per_core' accessible to the pseries_energy module. Instead of making an API to read threads_per_core, this is a higher level wrapper function to convert from logical cpu number to core number. The current APIs cpu_first_thread_in_core() and cpu_last_thread_in_core() returns logical CPU number while cpu_thread_to_core() returns core number or index which is not a logical CPU number. The new APIs are now clearly named to distinguish 'core number' versus first and last 'logical cpu number' in that core. The new APIs cpu_{first,last}_thread_sibling() work on logical cpu numbers. While cpu_first_thread_of_core() and cpu_core_index_of_thread() work on core index. Example usage: (4 threads per core system) cpu_first_thread_sibling(5) = 4 cpu_last_thread_sibling(5) = 7 cpu_core_index_of_thread(5) = 1 cpu_first_thread_of_core(1) = 4 cpu_core_index_of_thread() is used in cpu_to_drc_index() in the module and cpu_first_thread_of_core() is used in drc_index_to_cpu() in the module. Make API changes to few callers. Export symbols for use in modules. Signed-off-by: NVaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 02 9月, 2010 2 次提交
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由 Paul Mackerras 提交于
Currently, when CONFIG_VIRT_CPU_ACCOUNTING is enabled, we use the PURR register for measuring the user and system time used by processes, as well as other related times such as hardirq and softirq times. This turns out to be quite confusing for users because it means that a program will often be measured as taking less time when run on a multi-threaded processor (SMT2 or SMT4 mode) than it does when run on a single-threaded processor (ST mode), even though the program takes longer to finish. The discrepancy is accounted for as stolen time, which is also confusing, particularly when there are no other partitions running. This changes the accounting to use the timebase instead, meaning that the reported user and system times are the actual number of real-time seconds that the program was executing on the processor thread, regardless of which SMT mode the processor is in. Thus a program will generally show greater user and system times when run on a multi-threaded processor than on a single-threaded processor. On pSeries systems on POWER5 or later processors, we measure the stolen time (time when this partition wasn't running) using the hypervisor dispatch trace log. We check for new entries in the log on every entry from user mode and on every transition from kernel process context to soft or hard IRQ context (i.e. when account_system_vtime() gets called). So that we can correctly distinguish time stolen from user time and time stolen from system time, without having to check the log on every exit to user mode, we store separate timestamps for exit to user mode and entry from user mode. On systems that have a SPURR (POWER6 and POWER7), we read the SPURR in account_system_vtime() (as before), and then apportion the SPURR ticks since the last time we read it between scaled user time and scaled system time according to the relative proportions of user time and system time over the same interval. This avoids having to read the SPURR on every kernel entry and exit. On systems that have PURR but not SPURR (i.e., POWER5), we do the same using the PURR rather than the SPURR. This disables the DTL user interface in /sys/debug/kernel/powerpc/dtl for now since it conflicts with the use of the dispatch trace log by the time accounting code. Signed-off-by: NPaul Mackerras <paulus@samba.org> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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由 Michael Neuling 提交于
Simple cleanup by moving arch_sd_sibling_asym_packing from process.c to smp.c to save an #ifdef CONFIG_SMP No functionality change. Signed-off-by: NMichael Neuling <mikey@neuling.org> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 24 8月, 2010 1 次提交
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During CPU offline/online tests __cpu_up would flood the logs with the following message: Processor 0 found. This provides no useful information to the user as there is no context provided, and since the operation was a success (to this point) it is expected that the CPU will come back online, providing all the feedback necessary. Change the "Processor found" message to DBG() similar to other such messages in the same function. Also, add an appropriate log level for the "Processor is stuck" message. Signed-off-by: NDarren Hart <dvhltc@us.ibm.com> Acked-by: NWill Schmidt <will_schmidt@vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Nathan Fontenot <nfont@austin.ibm.com> Cc: Robert Jennings <rcj@linux.vnet.ibm.com> Cc: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 31 7月, 2010 1 次提交
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由 Tiejun Chen 提交于
We already defined start_cpu_decrementer() to invoke decrementer for AP as the following path: start_secondary() -> secondary_cpu_time_init() -> start_cpu_decrementer() So remove these incorrect codes introduced from commit: e7f75ad0 powerpc/47x: Base ppc476 support And actually we really should not enable decrementer before calling set_dec(). Signed-off-by: NTiejun Chen <tiejun.chen@windriver.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 29 7月, 2010 1 次提交
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由 Paul Mackerras 提交于
Since the decrementer and timekeeping code was moved over to using the generic clockevents and timekeeping infrastructure, several variables and functions have been obsolete and effectively unused. This deletes them. In particular, wakeup_decrementer() is no longer needed since the generic code reprograms the decrementer as part of the process of resuming the timekeeping code, which happens during sysdev resume. Thus the wakeup_decrementer calls in the suspend_enter methods for 52xx platforms have been removed. The call in the powermac cpu frequency change code has been replaced by set_dec(1), which will cause a timer interrupt as soon as interrupts are enabled, and the generic code will then reprogram the decrementer with the correct value. This also simplifies the generic_suspend_en/disable_irqs functions and makes them static since they are not referenced outside time.c. The preempt_enable/disable calls are removed because the generic code has disabled all but the boot cpu at the point where these functions are called, so we can't be moved to another cpu. Signed-off-by: NPaul Mackerras <paulus@samba.org> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 09 7月, 2010 1 次提交
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由 Paul Mackerras 提交于
Since the decrementer and timekeeping code was moved over to using the generic clockevents and timekeeping infrastructure, several variables and functions have been obsolete and effectively unused. This deletes them. In particular, wakeup_decrementer() is no longer needed since the generic code reprograms the decrementer as part of the process of resuming the timekeeping code, which happens during sysdev resume. Thus the wakeup_decrementer calls in the suspend_enter methods for 52xx platforms have been removed. The call in the powermac cpu frequency change code has been replaced by set_dec(1), which will cause a timer interrupt as soon as interrupts are enabled, and the generic code will then reprogram the decrementer with the correct value. This also simplifies the generic_suspend_en/disable_irqs functions and makes them static since they are not referenced outside time.c. The preempt_enable/disable calls are removed because the generic code has disabled all but the boot cpu at the point where these functions are called, so we can't be moved to another cpu. Signed-off-by: NPaul Mackerras <paulus@samba.org> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 21 5月, 2010 1 次提交
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由 Milton Miller 提交于
Configuring a powerpc 32 bit kernel for both SMP and SUSPEND turns on CPU_HOTPLUG to enable disable_nonboot_cpus to be called by the common suspend code. Previously the definition of cpu_die for ppc32 was in the powermac platform code, causing it to be undefined if that platform as not selected. arch/powerpc/kernel/built-in.o: In function 'cpu_idle': arch/powerpc/kernel/idle.c:98: undefined reference to 'cpu_die' Move the code from setup_64 to smp.c and rename the power mac versions to their specific names. Note that this does not setup the cpu_die pointers in either smp_ops (request a given cpu die) or ppc_md (make this cpu die), for other platforms but there are generic versions in smp.c. Reported-by: NMatt Sealey <matt@genesi-usa.com> Reported-by: NKumar Gala <galak@kernel.crashing.org> Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NAnton Vorontsov <avorontsov@mvista.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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