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* MIPS: Remove duplicated include from numa.cWei Yongjun2014-08-191-2/+0
| | | | | | | | | | Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: Huacai Chen <chenhc@lemote.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/7537/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: Add common plat_irq_dispatch declarationSergey Ryazanov2014-08-192-1/+2
| | | | | | | | | | Add common declaration to get rid of following sparse warning: "symbol 'plat_irq_dispatch' was not declared. Should it be static?" Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Cc: Linux MIPS <linux-mips@linux-mips.org> Patchwork: https://patchwork.linux-mips.org/patch/7539/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: MSP71xx: remove unused plat_irq_dispatch() argumentSergey Ryazanov2014-08-191-1/+1
| | | | | | | | | | Remove unused argument to make the plat_irq_dispatch() function declaration similar to the realization of other platforms. Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Cc: Linux MIPS <linux-mips@linux-mips.org> Patchwork: https://patchwork.linux-mips.org/patch/7538/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: GIC: Remove useless parens from GICBIS().Ralf Baechle2014-08-181-1/+1
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* MIPS: perf: Mark pmu interupt IRQF_NO_THREADYang Wei2014-08-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In RT kernel, I ran into the following calltrace, so PMU interrupts cannot be threaded in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0 INFO: lockdep is turned off. Call Trace: [<ffffffff8088595c>] dump_stack+0x1c/0x50 [<ffffffff801a958c>] __might_sleep+0x13c/0x148 [<ffffffff80891c54>] rt_spin_lock+0x3c/0xb0 [<ffffffff801ad29c>] __wake_up+0x3c/0x80 [<ffffffff80243ba4>] perf_event_wakeup+0x8c/0xf8 [<ffffffff80243c50>] perf_pending_event+0x40/0x78 [<ffffffff8023d88c>] irq_work_run+0x74/0xc0 [<ffffffff80152640>] mipsxx_pmu_handle_shared_irq+0x110/0x228 [<ffffffff8015276c>] mipsxx_pmu_handle_irq+0x14/0x30 [<ffffffff801ffda4>] handle_irq_event_percpu+0xbc/0x470 [<ffffffff80204478>] handle_percpu_irq+0x98/0xc8 [<ffffffff801ff284>] generic_handle_irq+0x4c/0x68 [<ffffffff8089748c>] do_IRQ+0x2c/0x48 [<ffffffff80105864>] plat_irq_dispatch+0x64/0xd0 [ralf@linux-mips.org: I don't see why based on this register dump the handler should be marked IRQF_NO_THREAD - but the handler is manipulating per-CPU resources so we don't want it to be rescheduled to another CPU.] Signed-off-by: Yang Wei <Wei.Yang@windriver.com> Cc: a.p.zijlstra@chello.nl Cc: paulus@samba.org Cc: mingo@redhat.com Cc: acme@kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7506/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* Merge branch 'release' of ↵Linus Torvalds2014-08-161-0/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux Pull idle update from Len Brown: "Two Intel-platform-specific updates to intel_idle, and a cosmetic tweak to the turbostat utility" * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: tools/power turbostat: tweak whitespace in output format intel_idle: Broadwell support intel_idle: Disable Baytrail Core and Module C6 auto-demotion
| * intel_idle: Disable Baytrail Core and Module C6 auto-demotionLen Brown2014-08-151-0/+3
| | | | | | | | | | | | | | | | | | | | Power efficiency improves on Baytrail (Intel Atom Processor E3000) when Linux disables C6 auto-demotion. Based on work by Srinidhi Kasagar <srinidhi.kasagar@intel.com>. Signed-off-by: Len Brown <len.brown@intel.com> Cc: x86@kernel.org
* | Merge tag 'pci-v3.17-changes-2' of ↵Linus Torvalds2014-08-142-6/+6
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull DEFINE_PCI_DEVICE_TABLE removal from Bjorn Helgaas: "Part two of the PCI changes for v3.17: - Remove DEFINE_PCI_DEVICE_TABLE macro use (Benoit Taine) It's a mechanical change that removes uses of the DEFINE_PCI_DEVICE_TABLE macro. I waited until later in the merge window to reduce conflicts, but it's possible you'll still see a few" * tag 'pci-v3.17-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: PCI: Remove DEFINE_PCI_DEVICE_TABLE macro use
| * | PCI: Remove DEFINE_PCI_DEVICE_TABLE macro useBenoit Taine2014-08-122-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We should prefer `struct pci_device_id` over `DEFINE_PCI_DEVICE_TABLE` to meet kernel coding style guidelines. This issue was reported by checkpatch. A simplified version of the semantic patch that makes this change is as follows (http://coccinelle.lip6.fr/): // <smpl> @@ identifier i; declarer name DEFINE_PCI_DEVICE_TABLE; initializer z; @@ - DEFINE_PCI_DEVICE_TABLE(i) + const struct pci_device_id i[] = z; // </smpl> [bhelgaas: add semantic patch] Signed-off-by: Benoit Taine <benoit.taine@lip6.fr> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
* | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparcLinus Torvalds2014-08-144-5/+71
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull Sparc fixes from David Miller: "Hook up the memfd syscall, and properly claim all PCI resources discovered when building the PCI device tree" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: sparc: Hook up memfd_create system call. sparc64: Properly claim resources as each PCI bus is probed. sparc64: Skip bogus PCI bridge ranges. sparc64: Expand PCI bridge probing debug logging.
| * | | sparc: Hook up memfd_create system call.David S. Miller2014-08-133-4/+5
| | | | | | | | | | | | | | | | Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | sparc64: Properly claim resources as each PCI bus is probed.David S. Miller2014-08-131-0/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Perform a pci_claim_resource() on all valid resources discovered during the OF device tree scan. Based almost entirely upon the PCI OF bus probing code which does the same thing there. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | sparc64: Skip bogus PCI bridge ranges.David S. Miller2014-08-131-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It seems that when a PCI Express bridge is not in use and has no devices behind it, the ranges property is bogus. Specifically the size property is of the form [0xffffffff:...], and if you add this size to the resource start address the 64-bit calculation will overflow. Just check specifically for this size value signature and skip them. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | sparc64: Expand PCI bridge probing debug logging.David S. Miller2014-08-131-1/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dump the various aspects of the PCI bridge probed at boot time, most importantly the bridge number ranges, and the ranges property. This helps diagnose PCI resource issues and other problems by giving ofpci_debug=1 on the boot command line. Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | Merge branch 'kbuild' of ↵Linus Torvalds2014-08-141-1/+1
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - make clean also considers $(extra-m) and $(extra-) to be consistent - cleanup and fixes in scripts/Makefile.host - allow to override the name of the Python 2 executable with make PYTHON=... (only needed for ia64 in practice) - option to split debugingo into *.dwo files to save disk space if the compiler supports it (CONFIG_DEBUG_INFO_SPLIT) - option to use dwarf4 debuginfo if the compiler supports it (CONFIG_DEBUG_INFO_DWARF4) - fix for disabling certain warnings with clang - fix for unneeded rebuild with dash when a command contains backslashes * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: kbuild: Fix handling of backslashes in *.cmd files kbuild, LLVMLinux: Supress warnings unless W=1-3 Kbuild: Add a option to enable dwarf4 v2 kbuild: Support split debug info v4 kbuild: allow to override Python command name kbuild: clean-up and bug fix of scripts/Makefile.host kbuild: clean up scripts/Makefile.host kbuild: drop shared library support from Makefile.host kbuild: fix a bug of C++ host program handling kbuild: fix a typo in scripts/Makefile.host scripts/Makefile.clean: clean also $(extra-m) and $(extra-)
| * | | | kbuild: allow to override Python command nameMasahiro Yamada2014-07-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The specification of Python 3 is largely different from that of Python 2. For example, arch/ia64/scripts/unwcheck.py seems to be written in Python 2, not compatible with Python 3. It is not a good idea to invoke python scripts with the hard-coded command name 'python'. The command 'python' could possibly be Python 3 on some systems. For that case, it is reasonable to allow to override the command name by giving 'PYTHON=python2' from the command line. The 'python' in arch/ia64/Makefile should be replaced with '$(PYTHON)'. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: linux-ia64@vger.kernel.org Signed-off-by: Michal Marek <mmarek@suse.cz>
* | | | | Merge branch 'next' of ↵Linus Torvalds2014-08-1428-223/+387
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull more powerpc updates from Ben Herrenschmidt: "Here are some more powerpc bits for 3.17, essentially fixes. The biggest series, also aimed at -stable, is from Aneesh and is the result of weeks and weeks of debugging to find out why the heck or THP implementation was occasionally triggering multi-hit errors in our level 1 TLB. It ended up being a combination of issues including subtleties as to how we should invalidate those special 'MPSS' pages we use to allow the use of 16M pages inside 4K/64K "base page size" segments (you really have to love our MMU !) Another interesting one in the "OMG" category is the series from Michael adding memory barriers to spin_is_locked(). That's also the result of many days of debugging to figure out why the semaphore code would occasionally crash in ways that made no sense. It ended up being some creative lock stacking that was defeated by the fact that our locks allow a load inside the locked section to be re-ordered with the load of the lock value itself (I'm still of two mind about whether to kill that once and for all by putting a heavier barrier back into our lock implementation...). The fixes come with a long explanation in the cset comments, feel free to read it if you feel like having a headache today" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits) powerpc/thp: Add tracepoints to track hugepage invalidate powerpc/mm: Use read barrier when creating real_pte powerpc/thp: Use ACCESS_ONCE when loading pmdp powerpc/thp: Invalidate with vpn in loop powerpc/thp: Handle combo pages in invalidate powerpc/thp: Invalidate old 64K based hash page mapping before insert of 4k pte powerpc/thp: Don't recompute vsid and ssize in loop on invalidate powerpc/thp: Add write barrier after updating the valid bit powerpc: reorder per-cpu NUMA information's initialization powerpc/perf/hv-24x7: Use kmem_cache_free powerpc/pseries/hvcserver: Fix endian issue in hvcs_get_partner_info powerpc: Hard disable interrupts in xmon powerpc: remove duplicate definition of TEXASR_FS powerpc/pseries: Avoid deadlock on removing ddw powerpc/pseries: Failure on removing device node powerpc/boot: Use correct zlib types for comparison powerpc/powernv: Interface to register/unregister opal dump region printk: Add function to return log buffer address and size powerpc: Add POWER8 features to CPU_FTRS_POSSIBLE/ALWAYS powerpc/ppc476: Disable BTAC ...
| * | | | | powerpc/thp: Add tracepoints to track hugepage invalidateAneesh Kumar K.V2014-08-132-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add tracepoint to track hugepage invalidate. This help us in debugging difficult to track bugs. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/mm: Use read barrier when creating real_pteAneesh Kumar K.V2014-08-131-5/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On ppc64 we support 4K hash pte with 64K page size. That requires us to track the hash pte slot information on a per 4k basis. We do that by storing the slot details in the second half of pte page. The pte bit _PAGE_COMBO is used to indicate whether the second half need to be looked while building real_pte. We need to use read memory barrier while doing that so that load of hidx is not reordered w.r.t _PAGE_COMBO check. On the store side we already do a lwsync in __hash_page_4K CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/thp: Use ACCESS_ONCE when loading pmdpAneesh Kumar K.V2014-08-131-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We would get wrong results in compiler recomputed old_pmd. Avoid that by using ACCESS_ONCE CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/thp: Invalidate with vpn in loopAneesh Kumar K.V2014-08-131-16/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As per ISA, for 4k base page size we compare 14..65 bits of VA specified with the entry_VA in tlb. That implies we need to make sure we do a tlbie with all the possible 4k va we used to access the 16MB hugepage. With 64k base page size we compare 14..57 bits of VA. Hence we cannot ignore the lower 24 bits of va while tlbie .We also cannot tlb invalidate a 16MB entry with just one tlbie instruction because we don't track which va was used to instantiate the tlb entry. CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/thp: Handle combo pages in invalidateAneesh Kumar K.V2014-08-133-5/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we changed base page size of the segment, either via sub_page_protect or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash table entries. We do a lazy hash page table flush for all mapped pages in the demoted segment. This happens when we handle hash page fault for these pages. We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte, that implies that we could possibly have older 64K hash pte entries in the hash page table and we need to invalidate those entries. Use _PAGE_COMBO to determine the page size with which we should invalidate the hash table entries on unmap. CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/thp: Invalidate old 64K based hash page mapping before insert of 4k pteAneesh Kumar K.V2014-08-131-9/+70
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we changed base page size of the segment, either via sub_page_protect or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash table entries. We do a lazy hash page table flush for all mapped pages in the demoted segment. This happens when we handle hash page fault for these pages. We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte, that implies that we could possibly have older 64K hash pte entries in the hash page table and we need to invalidate those entries. Handle this correctly for 16M pages CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/thp: Don't recompute vsid and ssize in loop on invalidateAneesh Kumar K.V2014-08-134-43/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The segment identifier and segment size will remain the same in the loop, So we can compute it outside. We also change the hugepage_invalidate interface so that we can use it the later patch CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/thp: Add write barrier after updating the valid bitAneesh Kumar K.V2014-08-131-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With hugepages, we store the hpte valid information in the pte page whose address is stored in the second half of the PMD. Use a write barrier to make sure clearing pmd busy bit and updating hpte valid info are ordered properly. CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc: reorder per-cpu NUMA information's initializationNishanth Aravamudan2014-08-132-9/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is an issue currently where NUMA information is used on powerpc (and possibly ia64) before it has been read from the device-tree, which leads to large slab consumption with CONFIG_SLUB and memoryless nodes. NUMA powerpc non-boot CPU's cpu_to_node/cpu_to_mem is only accurate after start_secondary(), similar to ia64, which is invoked via smp_init(). Commit 6ee0578b4daae ("workqueue: mark init_workqueues() as early_initcall()") made init_workqueues() be invoked via do_pre_smp_initcalls(), which is obviously before the secondary processors are online. Additionally, the following commits changed init_workqueues() to use cpu_to_node to determine the node to use for kthread_create_on_node: bce903809ab3f ("workqueue: add wq_numa_tbl_len and wq_numa_possible_cpumask[]") f3f90ad469342 ("workqueue: determine NUMA node of workers accourding to the allowed cpumask") Therefore, when init_workqueues() runs, it sees all CPUs as being on Node 0. On LPARs or KVM guests where Node 0 is memoryless, this leads to a high number of slab deactivations (http://www.spinics.net/lists/linux-mm/msg67489.html). Fix this by initializing the powerpc-specific CPU<->node/local memory node mapping as early as possible, which on powerpc is do_init_bootmem(). Currently that function initializes the mapping for the boot CPU, but we extend it to setup the mapping for all possible CPUs. Then, in smp_prepare_cpus(), we can correspondingly set the per-cpu values for all possible CPUs. That ensures that before the early_initcalls run (and really as early as possible), the per-cpu NUMA mapping is accurate. While testing memoryless nodes on PowerKVM guests with a fix to the workqueue logic to use cpu_to_mem() instead of cpu_to_node(), with a guest topology of: available: 2 nodes (0-1) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 node 0 size: 0 MB node 0 free: 0 MB node 1 cpus: 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 node 1 size: 16336 MB node 1 free: 15329 MB node distances: node 0 1 0: 10 40 1: 40 10 the slab consumption decreases from Slab: 932416 kB SUnreclaim: 902336 kB to Slab: 395264 kB SUnreclaim: 359424 kB And we a corresponding increase in the slab efficiency from slab mem objs slabs used active active ------------------------------------------------------------ kmalloc-16384 337 MB 11.28% 100.00% task_struct 288 MB 9.93% 100.00% to slab mem objs slabs used active active ------------------------------------------------------------ kmalloc-16384 37 MB 100.00% 100.00% task_struct 31 MB 100.00% 100.00% Powerpc didn't support memoryless nodes until recently (64bb80d87f01 "powerpc/numa: Enable CONFIG_HAVE_MEMORYLESS_NODES" and 8c272261194d "powerpc/numa: Enable USE_PERCPU_NUMA_NODE_ID"). Those commits also helped improve memory consumption with these kind of environments. Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/perf/hv-24x7: Use kmem_cache_freeHimangi Saraogi2014-08-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Free memory allocated using kmem_cache_zalloc using kmem_cache_free rather than kfree. The Coccinelle semantic patch that makes this change is as follows: // <smpl> @@ expression x,E,c; @@ x = \(kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache_alloc_node\)(c,...) ... when != x = E when != &x ?-kfree(x) +kmem_cache_free(c,x) // </smpl> Signed-off-by: Himangi Saraogi <himangi774@gmail.com> Acked-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/pseries/hvcserver: Fix endian issue in hvcs_get_partner_infoThomas Falcon2014-08-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A buffer returned by H_VTERM_PARTNER_INFO contains device information in big endian format, causing problems for little endian architectures. This patch ensures that they are in cpu endian. Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc: Hard disable interrupts in xmonAnton Blanchard2014-08-131-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xmon only soft disables interrupts. This seems like a bad idea - we certainly don't want decrementer and PMU exceptions going off when we are debugging something inside xmon. This issue was uncovered when the hard lockup detector went off inside xmon. To ensure we wont get a spurious hard lockup warning, I also call touch_nmi_watchdog() when exiting xmon. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc: remove duplicate definition of TEXASR_FSNishanth Aravamudan2014-08-131-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It appears that commits 7f06f21d40a6 ("powerpc/tm: Add checking to treclaim/trechkpt") and e4e38121507a ("KVM: PPC: Book3S HV: Add transactional memory support") both added definitions of TEXASR_FS. Remove one of them. At the same time, fix the alignment of the remaining definition (should be tab-separated like the rest of the #defines). Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/pseries: Avoid deadlock on removing ddwGavin Shan2014-08-131-6/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Function remove_ddw() could be called in of_reconfig_notifier and we potentially remove the dynamic DMA window property, which invokes of_reconfig_notifier again. Eventually, it leads to the deadlock as following backtrace shows. The patch fixes the above issue by deferring releasing the dynamic DMA window property while releasing the device node. ============================================= [ INFO: possible recursive locking detected ] 3.16.0+ #428 Tainted: G W --------------------------------------------- drmgr/2273 is trying to acquire lock: ((of_reconfig_chain).rwsem){.+.+..}, at: [<c000000000091890>] \ .__blocking_notifier_call_chain+0x40/0x78 but task is already holding lock: ((of_reconfig_chain).rwsem){.+.+..}, at: [<c000000000091890>] \ .__blocking_notifier_call_chain+0x40/0x78 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock((of_reconfig_chain).rwsem); lock((of_reconfig_chain).rwsem); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by drmgr/2273: #0: (sb_writers#4){.+.+.+}, at: [<c0000000001cbe70>] \ .vfs_write+0xb0/0x1f8 #1: ((of_reconfig_chain).rwsem){.+.+..}, at: [<c000000000091890>] \ .__blocking_notifier_call_chain+0x40/0x78 stack backtrace: CPU: 17 PID: 2273 Comm: drmgr Tainted: G W 3.16.0+ #428 Call Trace: [c0000000137e7000] [c000000000013d9c] .show_stack+0x88/0x148 (unreliable) [c0000000137e70b0] [c00000000083cd34] .dump_stack+0x7c/0x9c [c0000000137e7130] [c0000000000b8afc] .__lock_acquire+0x128c/0x1c68 [c0000000137e7280] [c0000000000b9a4c] .lock_acquire+0xe8/0x104 [c0000000137e7350] [c00000000083588c] .down_read+0x4c/0x90 [c0000000137e73e0] [c000000000091890] .__blocking_notifier_call_chain+0x40/0x78 [c0000000137e7490] [c000000000091900] .blocking_notifier_call_chain+0x38/0x48 [c0000000137e7520] [c000000000682a28] .of_reconfig_notify+0x34/0x5c [c0000000137e75b0] [c000000000682a9c] .of_property_notify+0x4c/0x54 [c0000000137e7650] [c000000000682bf0] .of_remove_property+0x30/0xd4 [c0000000137e76f0] [c000000000052a44] .remove_ddw+0x144/0x168 [c0000000137e7790] [c000000000053204] .iommu_reconfig_notifier+0x30/0xe0 [c0000000137e7820] [c00000000009137c] .notifier_call_chain+0x6c/0xb4 [c0000000137e78c0] [c0000000000918ac] .__blocking_notifier_call_chain+0x5c/0x78 [c0000000137e7970] [c000000000091900] .blocking_notifier_call_chain+0x38/0x48 [c0000000137e7a00] [c000000000682a28] .of_reconfig_notify+0x34/0x5c [c0000000137e7a90] [c000000000682e14] .of_detach_node+0x44/0x1fc [c0000000137e7b40] [c0000000000518e4] .ofdt_write+0x3ac/0x688 [c0000000137e7c20] [c000000000238430] .proc_reg_write+0xb8/0xd4 [c0000000137e7cd0] [c0000000001cbeac] .vfs_write+0xec/0x1f8 [c0000000137e7d70] [c0000000001cc3b0] .SyS_write+0x58/0xa0 [c0000000137e7e30] [c00000000000a064] syscall_exit+0x0/0x98 Cc: stable@vger.kernel.org Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/pseries: Failure on removing device nodeGavin Shan2014-08-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While running command "drmgr -c phb -r -s 'PHB 528'", following backtrace jumped out because the target device node isn't marked with OF_DETACHED by of_detach_node(), which caused by error returned from memory hotplug related reconfig notifier when disabling CONFIG_MEMORY_HOTREMOVE. The patch fixes it. ERROR: Bad of_node_put() on /pci@800000020000210/ethernet@0 CPU: 14 PID: 2252 Comm: drmgr Tainted: G W 3.16.0+ #427 Call Trace: [c000000012a776a0] [c000000000013d9c] .show_stack+0x88/0x148 (unreliable) [c000000012a77750] [c00000000083cd34] .dump_stack+0x7c/0x9c [c000000012a777d0] [c0000000006807c4] .of_node_release+0x58/0xe0 [c000000012a77860] [c00000000038a7d0] .kobject_release+0x174/0x1b8 [c000000012a77900] [c00000000038a884] .kobject_put+0x70/0x78 [c000000012a77980] [c000000000681680] .of_node_put+0x28/0x34 [c000000012a77a00] [c000000000681ea8] .__of_get_next_child+0x64/0x70 [c000000012a77a90] [c000000000682138] .of_find_node_by_path+0x1b8/0x20c [c000000012a77b40] [c000000000051840] .ofdt_write+0x308/0x688 [c000000012a77c20] [c000000000238430] .proc_reg_write+0xb8/0xd4 [c000000012a77cd0] [c0000000001cbeac] .vfs_write+0xec/0x1f8 [c000000012a77d70] [c0000000001cc3b0] .SyS_write+0x58/0xa0 [c000000012a77e30] [c00000000000a064] syscall_exit+0x0/0x98 Cc: stable@vger.kernel.org Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/boot: Use correct zlib types for comparisonBenjamin Herrenschmidt2014-08-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Avoids this warning: arch/powerpc/boot/gunzip_util.c:118:9: warning: comparison of distinct pointer types lacks a cast Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/powernv: Interface to register/unregister opal dump regionVasant Hegde2014-08-133-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PowerNV platform is capable of capturing host memory region when system crashes (because of host/firmware). We have new OPAL API to register/ unregister memory region to be captured when system crashes. This patch adds support for new API. Also during boot time we register kernel log buffer and unregister before doing kexec. Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc: Add POWER8 features to CPU_FTRS_POSSIBLE/ALWAYSMichael Ellerman2014-08-131-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have been a bit slack about updating the CPU_FTRS_POSSIBLE and CPU_FTRS_ALWAYS masks. When we added POWER8, and also POWER8E we forgot to update the ALWAYS mask. And when we added POWER8_DD1 we forgot to update both the POSSIBLE and ALWAYS masks. Luckily this hasn't caused any actual bugs AFAICS. Failing to update the ALWAYS mask just forgoes a potential optimisation opportunity. Failing to update the POSSIBLE mask for POWER8_DD1 is also OK because it only removes a bit rather than adding any. Regardless they should all be in both masks so as to avoid any future bugs when the set of ALWAYS/POSSIBLE bits changes, or the masks themselves change. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Michael Neuling <mikey@neuling.org> Acked-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/ppc476: Disable BTACAlistair Popple2014-08-131-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch disables the branch target address CAM which under specific circumstances may cause the processor to skip execution of 1-4 instructions. This fixes IBM Erratum #47. Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/powernv: Fix IOMMU group lostGavin Shan2014-08-132-18/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we take full hotplug to recover from EEH errors, PCI buses could be involved. For the case, the child devices of involved PCI buses can't be attached to IOMMU group properly, which is caused by commit 3f28c5a ("powerpc/powernv: Reduce multi-hit of iommu_add_device()"). When adding the PCI devices of the newly created PCI buses to the system, the IOMMU group is expected to be added in (C). (A) fails to bind the IOMMU group because bus->is_added is false. (B) fails because the device doesn't have binding IOMMU table yet. bus->is_added is set to true at end of (C) and pdev->is_added is set to true at (D). pcibios_add_pci_devices() pci_scan_bridge() pci_scan_child_bus() pci_scan_slot() pci_scan_single_device() pci_scan_device() pci_device_add() pcibios_add_device() A: Ignore device_add() B: Ignore pcibios_fixup_bus() pcibios_setup_bus_devices() pcibios_setup_device() C: Hit pcibios_finish_adding_to_bus() pci_bus_add_devices() pci_bus_add_device() D: Add device If the parent PCI bus isn't involved in hotplug, the IOMMU group is expected to be bound in (B). (A) should fail as the sysfs entries aren't populated. The patch fixes the issue by reverting commit 3f28c5a and remove WARN_ON() in iommu_add_device() to allow calling the function even the specified device already has associated IOMMU group. Cc: <stable@vger.kernel.org> # 3.16+ Reported-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Acked-by: Wei Yang <weiyang@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc: Add smp_mb()s to arch_spin_unlock_wait()Michael Ellerman2014-08-131-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Similar to the previous commit which described why we need to add a barrier to arch_spin_is_locked(), we have a similar problem with spin_unlock_wait(). We need a barrier on entry to ensure any spinlock we have previously taken is visibly locked prior to the load of lock->slock. It's also not clear if spin_unlock_wait() is intended to have ACQUIRE semantics. For now be conservative and add a barrier on exit to give it ACQUIRE semantics. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc: Add smp_mb() to arch_spin_is_locked()Michael Ellerman2014-08-131-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel defines the function spin_is_locked(), which can be used to check if a spinlock is currently locked. Using spin_is_locked() on a lock you don't hold is obviously racy. That is, even though you may observe that the lock is unlocked, it may become locked at any time. There is (at least) one exception to that, which is if two locks are used as a pair, and the holder of each checks the status of the other before doing any update. Assuming *A and *B are two locks, and *COUNTER is a shared non-atomic value: The first CPU does: spin_lock(*A) if spin_is_locked(*B) # nothing else smp_mb() LOAD r = *COUNTER r++ STORE *COUNTER = r spin_unlock(*A) And the second CPU does: spin_lock(*B) if spin_is_locked(*A) # nothing else smp_mb() LOAD r = *COUNTER r++ STORE *COUNTER = r spin_unlock(*B) Although this is a strange locking construct, it should work. It seems to be understood, but not documented, that spin_is_locked() is not a memory barrier, so in the examples above and below the caller inserts its own memory barrier before acting on the result of spin_is_locked(). For now we assume spin_is_locked() is implemented as below, and we break it out in our examples: bool spin_is_locked(*LOCK) { LOAD l = *LOCK return l.locked } Our intuition is that there should be no problem even if the two code sequences run simultaneously such as: CPU 0 CPU 1 ================================================== spin_lock(*A) spin_lock(*B) LOAD b = *B LOAD a = *A if b.locked # true if a.locked # true # nothing # nothing spin_unlock(*A) spin_unlock(*B) If one CPU gets the lock before the other then it will do the update and the other CPU will back off: CPU 0 CPU 1 ================================================== spin_lock(*A) LOAD b = *B spin_lock(*B) if b.locked # false LOAD a = *A else if a.locked # true smp_mb() # nothing LOAD r1 = *COUNTER spin_unlock(*B) r1++ STORE *COUNTER = r1 spin_unlock(*A) However in reality spin_lock() itself is not indivisible. On powerpc we implement it as a load-and-reserve and store-conditional. Ignoring the retry logic for the lost reservation case, it boils down to: spin_lock(*LOCK) { LOAD l = *LOCK l.locked = true STORE *LOCK = l ACQUIRE_BARRIER } The ACQUIRE_BARRIER is required to give spin_lock() ACQUIRE semantics as defined in memory-barriers.txt: This acts as a one-way permeable barrier. It guarantees that all memory operations after the ACQUIRE operation will appear to happen after the ACQUIRE operation with respect to the other components of the system. On modern powerpc systems we use lwsync for ACQUIRE_BARRIER. lwsync is also know as "lightweight sync", or "sync 1". As described in Power ISA v2.07 section B.2.1.1, in this scenario the lwsync is not the barrier itself. It instead causes the LOAD of *LOCK to act as the barrier, preventing any loads or stores in the locked region from occurring prior to the load of *LOCK. Whether this behaviour is in accordance with the definition of ACQUIRE semantics in memory-barriers.txt is open to discussion, we may switch to a different barrier in future. What this means in practice is that the following can occur: CPU 0 CPU 1 ================================================== LOAD a = *A LOAD b = *B a.locked = true b.locked = true LOAD b = *B LOAD a = *A STORE *A = a STORE *B = b if b.locked # false if a.locked # false else else smp_mb() smp_mb() LOAD r1 = *COUNTER LOAD r2 = *COUNTER r1++ r2++ STORE *COUNTER = r1 STORE *COUNTER = r2 # Lost update spin_unlock(*A) spin_unlock(*B) That is, the load of *B can occur prior to the store that makes *A visibly locked. And similarly for CPU 1. The result is both CPUs hold their lock and believe the other lock is unlocked. The easiest fix for this is to add a full memory barrier to the start of spin_is_locked(), so adding to our previous definition would give us: bool spin_is_locked(*LOCK) { smp_mb() LOAD l = *LOCK return l.locked } The new barrier orders the store to the lock we are locking vs the load of the other lock: CPU 0 CPU 1 ================================================== LOAD a = *A LOAD b = *B a.locked = true b.locked = true STORE *A = a STORE *B = b smp_mb() smp_mb() LOAD b = *B LOAD a = *A if b.locked # true if a.locked # true # nothing # nothing spin_unlock(*A) spin_unlock(*B) Although the above example is theoretical, there is code similar to this example in sem_lock() in ipc/sem.c. This commit in addition to the next commit appears to be a fix for crashes we are seeing in that code where we believe this race happens in practice. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc: Fix "attempt to move .org backwards" errorGuenter Roeck2014-08-131-55/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Once again, we see arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:865: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:866: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:890: Error: attempt to move .org backwards when compiling ppc:allmodconfig. This time the problem has been caused by to commit 0869b6fd209bda ("powerpc/book3s: Add basic infrastructure to handle HMI in Linux"), which adds functions hmi_exception_early and hmi_exception_after_realmode into a critical (size-limited) code area, even though that does not appear to be necessary. Move those functions to a non-critical area of the file. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | powerpc/nohash: Split __early_init_mmu() into boot and secondaryScott Wood2014-08-131-45/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __early_init_mmu() does some things that are really only needed by the boot cpu. On FSL booke, This includes calling memblock_enforce_memory_limit(), which is labelled __init. Secondary cpu init code can't be __init as that would break CPU hotplug. While it's probably a bug that memblock_enforce_memory_limit() isn't __init_memblock instead, there's no reason why we should be doing this stuff for secondary cpus in the first place. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | | | | | Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linuxLinus Torvalds2014-08-149-93/+14
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull device tree updates from Grant Likely: "The branch contains the following device tree changes the v3.17 merge window: Group changes to the device tree. In preparation for adding device tree overlay support, OF_DYNAMIC is reworked so that a set of device tree changes can be prepared and applied to the tree all at once. OF_RECONFIG notifiers see the most significant change here so that users always get a consistent view of the tree. Notifiers generation is moved from before a change to after it, and notifiers for a group of changes are emitted after the entire block of changes have been applied Automatic console selection from DT. Console drivers can now use of_console_check() to see if the device node is specified as a console device. If so then it gets added as a preferred console. UART devices get this support automatically when uart_add_one_port() is called. DT unit tests no longer depend on pre-loaded data in the device tree. Data is loaded dynamically at the start of unit tests, and then unloaded again when the tests have completed. Also contains a few bugfixes for reserved regions and early memory setup" * tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux: (21 commits) of: Fixing OF Selftest build error drivers: of: add automated assignment of reserved regions to client devices of: Use proper types for checking memory overflow of: typo fix in __of_prop_dup() Adding selftest testdata dynamically into live tree of: Add todo tasklist for Devicetree of: Transactional DT support. of: Reorder device tree changes and notifiers of: Move dynamic node fixups out of powerpc and into common code of: Make sure attached nodes don't carry along extra children of: Make devicetree sysfs update functions consistent. of: Create unlocked versions of node and property add/remove functions OF: Utility helper functions for dynamic nodes of: Move CONFIG_OF_DYNAMIC code into a separate file of: rename of_aliases_mutex to just of_mutex of/platform: Fix of_platform_device_destroy iteration of devices of: Migrate of_find_node_by_name() users to for_each_node_by_name() tty: Update hypervisor tty drivers to use core stdout parsing code. arm/versatile: Add the uart as the stdout device. of: Enable console on serial ports specified by /chosen/stdout-path ...
| * \ \ \ \ \ Merge branch 'devicetree/next-overlay' into devicetree/nextGrant Likely2014-08-112-71/+1
| |\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/of/testcase-data/testcases.dts
| | * | | | | | of: Reorder device tree changes and notifiersGrant Likely2014-07-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, devicetree reconfig notifiers get emitted before the change is applied to the tree, but that behaviour is problematic if the receiver wants the determine the new state of the tree. The current users don't care, but the changeset code to follow will be making multiple changes at once. Reorder notifiers to get emitted after the change has been applied to the tree so that callbacks see the new tree state. At the same time, fixup the existing callbacks to expect the new order. There are a few callbacks that compare the old and new values of a changed property. Put both property pointers into the of_prop_reconfig structure. The current notifiers also allow the notifier callback to fail and cancel the change to the tree, but that feature isn't actually used. It really isn't valid to ignore a tree modification provided by firmware anyway, so remove the ability to cancel a change to the tree. Signed-off-by: Grant Likely <grant.likely@linaro.org> Cc: Nathan Fontenot <nfont@austin.ibm.com>
| | * | | | | | of: Move dynamic node fixups out of powerpc and into common codeGrant Likely2014-07-231-70/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PowerPC does an odd thing with dynamic nodes. It uses a notifier to catch new node additions and set some of the values like name and type. This makes no sense since that same code can be put directly into of_attach_node(). Besides, all dynamic node users need this, not just powerpc. Fix this problem by moving the logic out of arch/powerpc and into drivers/of/dynamic.c. It is also important to remove this notifier because we want to move the firing of notifiers from before the tree is modified to after so that the receiver gets a consistent view of the tree, but that is incompatible with notifiers that modify the node. Signed-off-by: Grant Likely <grant.likely@linaro.org> Cc: Nathan Fontenot <nfont@austin.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | | | | Merge branch 'devicetree/next-console' into devicetree/nextGrant Likely2014-08-116-20/+13
| |\ \ \ \ \ \ \
| | * | | | | | | of: Migrate of_find_node_by_name() users to for_each_node_by_name()Grant Likely2014-06-265-20/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are a bunch of users open coding the for_each_node_by_name() by calling of_find_node_by_name() directly instead of using the macro. This is getting in the way of some cleanups, and the possibility of removing of_find_node_by_name() entirely. Clean it up so that all the users are consistent. Signed-off-by: Grant Likely <grant.likely@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Takashi Iwai <tiwai@suse.de>
| | * | | | | | | arm/versatile: Add the uart as the stdout device.Grant Likely2014-06-261-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a stdout-path property to the Versatile devicetree so that automatic console selection works without needing a console= line on the kernel command line. Signed-off-by: Grant Likely <grant.likely@linaro.org>
| * | | | | | | | Adding selftest testdata dynamically into live treeGaurav Minocha2014-07-251-2/+0
| | |/ / / / / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch attaches selftest's device tree data (required by /drivers/of/selftest.c) dynamically into live device tree. First, it links selftest device tree data into the kernel image and then iterates over all the nodes and attaches them into the live tree. Once the testcases are complete, it removes the data attached. This patch will remove the manual process of addition and removal of selftest device tree data into the machine's dts file. Tested successfully with current selftest's testcases. Signed-off-by: Gaurav Minocha <gaurav.minocha.os@gmail.com> [glikely: Removed ability to build as a module and fixed no-devicetree bug] Signed-off-by: Grant Likely <grant.likely@linaro.org>
* | | | | | | | Merge tag 'stable/for-linus-3.17-b-rc0-tag' of ↵Linus Torvalds2014-08-143-11/+6
|\ \ \ \ \ \ \ \ | |_|_|_|_|/ / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen bugfixes from David Vrabel: - fix ARM build - fix boot crash with PVH guests - improve reliability of resume/migration * tag 'stable/for-linus-3.17-b-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: use vmap() to map grant table pages in PVH guests x86/xen: resume timer irqs early arm/xen: remove duplicate arch_gnttab_init() function