lwn.git/arch/powerpc/include/asm/smp.h, branch standardize-docs

powerpc/64s: implement arch-specific hardlockup watchdog

2017-07-12T23:26:02+00:00

Implement an arch-speicfic watchdog rather than use the perf-based hardlockup detector. The new watchdog takes the soft-NMI directly, rather than going through perf. Perf interrupts are to be made maskable in future, so that would prevent the perf detector from working in those regions. Additionally, implement a SMP based detector where all CPUs watch one another by pinging a shared cpumask. This is because powerpc Book3S does not have a true periodic local NMI, but some platforms do implement a true NMI IPI. If a CPU is stuck with interrupts hard disabled, the soft-NMI watchdog does not work, but the SMP watchdog will. Even on platforms without a true NMI IPI to get a good trace from the stuck CPU, other CPUs will notice the lockup sufficiently to report it and panic. [npiggin@gmail.com: honor watchdog disable at boot/hotplug] Link: http://lkml.kernel.org/r/20170621001346.5bb337c9@roar.ozlabs.ibm.com [npiggin@gmail.com: fix false positive warning at CPU unplug] Link: http://lkml.kernel.org/r/20170630080740.20766-1-npiggin@gmail.com [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20170616065715.18390-6-npiggin@gmail.com Signed-off-by: Nicholas Piggin Reviewed-by: Don Zickus Tested-by: Babu Moger [sparc] Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

powerpc: Add struct smp_ops_t.cause_nmi_ipi operation

2017-04-28T11:02:25+00:00

Have the NMI IPI code use this op when the platform defines it. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc: Add NMI IPI infrastructure

2017-04-28T11:02:25+00:00

Add a simple NMI IPI system that handles concurrency and reentrancy. The platform does not have to implement a true non-maskable interrupt, the default is to simply use the debugger break IPI message. This has now been co-opted for a general IPI message, and users (debugger and crash) have been reimplemented on top of the NMI system. Signed-off-by: Nicholas Piggin [mpe: Incorporate incremental fixes from Nick] Signed-off-by: Michael Ellerman

powerpc: Introduce msgsnd/doorbell barrier primitives

2017-04-13T13:34:33+00:00

POWER9 changes requirements and adds new instructions for synchronization. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc: Change the doorbell IPI calling convention

2017-04-13T13:34:33+00:00

Change the doorbell callers to know about their msgsnd addressing, rather than have them set a per-cpu target data tag at boot that gets sent to the cause_ipi functions. The data is only used for doorbell IPI functions, no other IPI types, so it makes sense to keep that detail local to doorbell. Have the platform code understand doorbell IPIs, rather than the interrupt controller code understand them. Platform code can look at capabilities it has available and decide which to use. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/smp: Remove migrate_irq() custom implementation

2017-04-07T02:01:27+00:00

Some powerpc platforms use this to move IRQs away from a CPU being unplugged. This function has several bugs such as not taking the right locks or failing to NULL check pointers. There's a new generic function doing exactly the same thing without all the bugs, so let's use it instead. mpe: The obvious place for the select of GENERIC_IRQ_MIGRATION is on HOTPLUG_CPU, but that doesn't work. On some configs PM_SLEEP_SMP will select HOTPLUG_CPU even though its dependencies are not met, which means the select of GENERIC_IRQ_MIGRATION doesn't happen. That leads to the build breaking. Fix it by moving the select of GENERIC_IRQ_MIGRATION to SMP. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc: Add optional smp_ops->prepare_cpu SMP callback

2017-04-06T09:58:53+00:00

Some platforms (will) need to perform allocations before bringing a new CPU online. Doing it from smp_ops->setup_cpu is the wrong thing to do: - It has no useful failure path (too late) - Calling any allocator will enable interrupts prematurely causing problems with large decrementer among others Instead, add a new callback that is called from __cpu_up (so from the context trying to online the new CPU) at a point where we can safely allocate and handle failures. This will be used by XIVE support. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc: Change places using CONFIG_KEXEC to use CONFIG_KEXEC_CORE instead.

2016-11-30T12:15:11+00:00

Commit 2965faa5e03d ("kexec: split kexec_load syscall from kexec core code") introduced CONFIG_KEXEC_CORE so that CONFIG_KEXEC means whether the kexec_load system call should be compiled-in and CONFIG_KEXEC_FILE means whether the kexec_file_load system call should be compiled-in. These options can be set independently from each other. Since until now powerpc only supported kexec_load, CONFIG_KEXEC and CONFIG_KEXEC_CORE were synonyms. That is not the case anymore, so we need to make a distinction. Almost all places where CONFIG_KEXEC was being used should be using CONFIG_KEXEC_CORE instead, since kexec_file_load also needs that code compiled in. Signed-off-by: Thiago Jung Bauermann Signed-off-by: Michael Ellerman

powerpc: Merge 32-bit and 64-bit setup_arch()

2016-07-21T09:17:46+00:00

There is little enough differences now. mpe: Add a/p/k/setup.h to contain the prototypes and empty versions of functions we need, rather than using weak functions. Add a few other empty versions to avoid as many #ifdefs as possible in the code. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

Merge tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2016-03-19T22:38:41+00:00

Pull powerpc updates from Michael Ellerman: "This was delayed a day or two by some build-breakage on old toolchains which we've now fixed. There's two PCI commits both acked by Bjorn. There's one commit to mm/hugepage.c which is (co)authored by Kirill. Highlights: - Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V - Add POWER9 cputable entry from Michael Neuling - FPU/Altivec/VSX save/restore optimisations from Cyril Bur - Add support for new ftrace ABI on ppc64le from Torsten Duwe Various cleanups & minor fixes from: - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh. General: - atomics: Allow architectures to define their own __atomic_op_* helpers from Boqun Feng - Implement atomic{, 64}_*_return_* variants and acquire/release/ relaxed variants for (cmp)xchg from Boqun Feng - Add powernv_defconfig from Jeremy Kerr - Fix BUG_ON() reporting in real mode from Balbir Singh - Add xmon command to dump OPAL msglog from Andrew Donnellan - Add xmon command to dump process/task similar to ps(1) from Douglas Miller - Clean up memory hotplug failure paths from David Gibson pci/eeh: - Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei Yang. - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan. - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang - PCI: Add pcibios_bus_add_device() weak function from Wei Yang - MAINTAINERS: Update EEH details and maintainership from Russell Currey cxl: - Support added to the CXL driver for running on both bare-metal and hypervisor systems, from Christophe Lombard and Frederic Barrat. - Ignore probes for virtual afu pci devices from Vaibhav Jain perf: - Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu - hv-24x7: Fix usage with chip events, display change in counter values, display domain indices in sysfs, eliminate domain suffix in event names, from Sukadev Bhattiprolu Freescale: - Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and other dt bits, and minor fixes/cleanup" * tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits) powerpc: Fix unrecoverable SLB miss during restore_math() powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers powerpc/rcpm: Fix build break when SMP=n powerpc/book3e-64: Use hardcoded mttmr opcode powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible powerpc/T104xRDB: add tdm riser card node to device tree powerpc32: PAGE_EXEC required for inittext powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s) powerpc/86xx: Introduce and use common dtsi powerpc/86xx: Update device tree powerpc/86xx: Move dts files to fsl directory powerpc/86xx: Switch to kconfig fragments approach powerpc/86xx: Update defconfigs powerpc/86xx: Consolidate common platform code powerpc32: Remove one insn in mulhdu powerpc32: small optimisation in flush_icache_range() powerpc: Simplify test in __dma_sync() powerpc32: move xxxxx_dcache_range() functions inline powerpc32: Remove clear_pages() and define clear_page() inline ...