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* Merge branch 'for-2.6.28' of git://linux-nfs.org/~bfields/linuxLinus Torvalds2008-10-142-1/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-2.6.28' of git://linux-nfs.org/~bfields/linux: (59 commits) svcrdma: Fix IRD/ORD polarity svcrdma: Update svc_rdma_send_error to use DMA LKEY svcrdma: Modify the RPC reply path to use FRMR when available svcrdma: Modify the RPC recv path to use FRMR when available svcrdma: Add support to svc_rdma_send to handle chained WR svcrdma: Modify post recv path to use local dma key svcrdma: Add a service to register a Fast Reg MR with the device svcrdma: Query device for Fast Reg support during connection setup svcrdma: Add FRMR get/put services NLM: Remove unused argument from svc_addsock() function NLM: Remove "proto" argument from lockd_up() NLM: Always start both UDP and TCP listeners lockd: Remove unused fields in the nlm_reboot structure lockd: Add helper to sanity check incoming NOTIFY requests lockd: change nlmclnt_grant() to take a "struct sockaddr *" lockd: Adjust nlmsvc_lookup_host() to accomodate AF_INET6 addresses lockd: Adjust nlmclnt_lookup_host() signature to accomodate non-AF_INET lockd: Support non-AF_INET addresses in nlm_lookup_host() NLM: Convert nlm_lookup_host() to use a single argument svcrdma: Add Fast Reg MR Data Types ...
| * Configure out file locking featuresThomas Petazzoni2008-09-292-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the CONFIG_FILE_LOCKING option which allows to remove support for advisory locks. With this patch enabled, the flock() system call, the F_GETLK, F_SETLK and F_SETLKW operations of fcntl() and NFS support are disabled. These features are not necessarly needed on embedded systems. It allows to save ~11 Kb of kernel code and data: text data bss dec hex filename 1125436 118764 212992 1457192 163c28 vmlinux.old 1114299 118564 212992 1445855 160fdf vmlinux -11137 -200 0 -11337 -2C49 +/- This patch has originally been written by Matt Mackall <mpm@selenic.com>, and is part of the Linux Tiny project. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Signed-off-by: Matt Mackall <mpm@selenic.com> Cc: matthew@wil.cx Cc: linux-fsdevel@vger.kernel.org Cc: mpm@selenic.com Cc: akpm@linux-foundation.org Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* | Merge branch 'proc' of ↵Linus Torvalds2008-10-132-13/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc * 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc: proc: remove kernel.maps_protect proc: remove now unneeded ADDBUF macro [PATCH] proc: show personality via /proc/pid/personality [PATCH] signal, procfs: some lock_task_sighand() users do not need rcu_read_lock() proc: move PROC_PAGE_MONITOR to fs/proc/Kconfig proc: make grab_header() static proc: remove unused get_dma_list() proc: remove dummy vmcore_open() proc: proc_sys_root tweak proc: fix return value of proc_reg_open() in "too late" case Fixed up trivial conflict in removed file arch/sparc/include/asm/dma_32.h
| * | proc: remove kernel.maps_protectAlexey Dobriyan2008-10-101-11/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit 831830b5a2b5d413407adf380ef62fe17d6fcbf2 aka "restrict reading from /proc/<pid>/maps to those who share ->mm or can ptrace" sysctl stopped being relevant because commit moved security checks from ->show time to ->start time (mm_for_maps()). Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Kees Cook <kees.cook@canonical.com>
| * | [PATCH] signal, procfs: some lock_task_sighand() users do not need ↵Lai Jiangshan2008-10-101-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rcu_read_lock() lock_task_sighand() make sure task->sighand is being protected, so we do not need rcu_read_lock(). [ exec() will get task->sighand->siglock before change task->sighand! ] But code using rcu_read_lock() _just_ to protect lock_task_sighand() only appear in procfs. (and some code in procfs use lock_task_sighand() without such redundant protection.) Other subsystem may put lock_task_sighand() into rcu_read_lock() critical region, but these rcu_read_lock() are used for protecting "for_each_process()", "find_task_by_vpid()" etc. , not for protecting lock_task_sighand(). Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> [ok from Oleg] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
* | | tty: Fix abusers of current->sighand->ttyAlan Cox2008-10-132-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | Various people outside the tty layer still stick their noses in behind the scenes. We need to make sure they also obey the locking and referencing rules. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | tty: Move tty_write_message out of kernel/printkAlan Cox2008-10-131-16/+0
| | | | | | | | | | | | | | | | | | | | | | | | This is pure tty code so put it in the tty layer where it can be with the locking relevant material it uses Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | tty: Add a kref countAlan Cox2008-10-132-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | Introduce a kref to the tty structure and use it to protect the tty->signal tty references. For now we don't introduce it for anything else. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge branch 'master' of ↵David S. Miller2008-10-1126-468/+900
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: sound/core/memalloc.c
| * \ \ Merge phase #4 (X2APIC, APIC unification, CPU identification unification) of ↵Linus Torvalds2008-10-112-1/+76
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-v28-for-linus-phase4-D' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (186 commits) x86, debug: print more information about unknown CPUs x86 setup: handle more than 8 CPU flag words x86: cpuid, fix typo x86: move transmeta cap read to early_init_transmeta() x86: identify_cpu_without_cpuid v2 x86: extended "flags" to show virtualization HW feature in /proc/cpuinfo x86: move VMX MSRs to msr-index.h x86: centaur_64.c remove duplicated setting of CONSTANT_TSC x86: intel.c put workaround for old cpus together x86: let intel 64-bit use intel.c x86: make intel_64.c the same as intel.c x86: make intel.c have 64-bit support code x86: little clean up of intel.c/intel_64.c x86: make 64 bit to use amd.c x86: make amd_64 have 32 bit code x86: make amd.c have 64bit support code x86: merge header in amd_64.c x86: add srat_detect_node for amd64 x86: remove duplicated force_mwait x86: cpu make amd.c more like amd_64.c v2 ...
| | * \ \ Merge branch 'x86/unify-cpu-detect' into x86-v28-for-linus-phase4-DIngo Molnar2008-10-111-0/+68
| | |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/kernel/cpu/common.c arch/x86/kernel/signal_64.c include/asm-x86/cpufeature.h
| | | * \ \ Merge commit 'v2.6.27-rc6' into x86/unify-cpu-detectIngo Molnar2008-09-1010-168/+361
| | | |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/kernel/cpu/amd.c arch/x86/kernel/cpu/common.c arch/x86/kernel/cpu/common_64.c arch/x86/kernel/cpu/feature_names.c include/asm-x86/cpufeature.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | * \ \ \ Merge branch 'x86/core' into x86/unify-cpu-detectIngo Molnar2008-09-052-1/+76
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| | | | * \ \ \ Merge branch 'core/resources' into x86/coreIngo Molnar2008-09-041-0/+68
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| | | | | * | | | IO resources: add reserve_region_with_split()Yinghai Lu2008-09-041-0/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add reserve_region_with_split() to not lose e820 reserved entries if they overlap with existing IO regions: with test case by extend 0xe0000000 - 0xeffffff to 0xdd800000 - we get: e0000000-efffffff : PCI MMCONFIG 0 e0000000-efffffff : reserved and in /proc/iomem we get: found conflict for reserved [dd800000, efffffff], try to reserve with split __reserve_region_with_split: (PCI Bus #80) [dd000000, ddffffff], res: (reserved) [dd800000, efffffff] __reserve_region_with_split: (PCI Bus #00) [de000000, dfffffff], res: (reserved) [de000000, efffffff] initcall pci_subsys_init+0x0/0x121 returned 0 after 381 msecs in dmesg various fixes and improvements suggested by Linus. Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | | * | | | | Merge branch 'linus' into x86/coreH. Peter Anvin2008-09-0413-157/+173
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| | | | * | | | | Merge branch 'x86/cpu' into x86/coreH. Peter Anvin2008-09-0420-88/+135
| | | | |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/kernel/cpu/feature_names.c include/asm-x86/cpufeature.h
| | * | | \ \ \ \ \ Merge branch 'x86/apic' into x86-v28-for-linus-phase4-BIngo Molnar2008-10-111-1/+8
| | |\ \ \ \ \ \ \ \ | | | | |/ / / / / / | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/kernel/apic_32.c arch/x86/kernel/apic_64.c arch/x86/kernel/setup.c drivers/pci/intel-iommu.c include/asm-x86/cpufeature.h include/asm-x86/dma-mapping.h
| | | * | | | | | | Merge branch 'linus' into x86/coreIngo Molnar2008-08-1434-441/+724
| | | |\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/kernel/genapic_64.c include/asm-x86/kvm_host.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | * \ \ \ \ \ \ \ Merge commit 'v2.6.27-rc1' into x86/coreIngo Molnar2008-07-3032-480/+962
| | | |\ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: include/asm-x86/dma-mapping.h include/asm-x86/namei.h include/asm-x86/uaccess.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | * \ \ \ \ \ \ \ \ Merge branch 'x86/x2apic' into x86/coreIngo Molnar2008-07-261-1/+8
| | | |\ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: include/asm-x86/i8259.h include/asm-x86/msidef.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | | * \ \ \ \ \ \ \ \ Merge branch 'linus' into x86/x2apicIngo Molnar2008-07-2536-685/+1125
| | | | |\ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/pci/dmar.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | | * \ \ \ \ \ \ \ \ \ Merge branch 'linus' into x86/x2apicIngo Molnar2008-07-221-1/+1
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| | | | * \ \ \ \ \ \ \ \ \ \ Merge branch 'linus' into x86/x2apicIngo Molnar2008-07-1863-1140/+11466
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| | | | * | | | | | | | | | | | x64, x2apic/intr-remap: generic irq migration support from process contextSuresh Siddha2008-07-121-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Generic infrastructure for migrating the irq from the process context in the presence of CONFIG_GENERIC_PENDING_IRQ. This will be used later for migrating irq in the presence of interrupt-remapping. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: akpm@linux-foundation.org Cc: arjan@linux.intel.com Cc: andi@firstfloor.org Cc: ebiederm@xmission.com Cc: jbarnes@virtuousgeek.org Cc: steiner@sgi.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | | | | | | | | Merge phase #3 (IOMMU) of ↵Linus Torvalds2008-10-111-0/+2
| |\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-v28-for-linus-phase3-B' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (74 commits) AMD IOMMU: use iommu_device_max_index, fix AMD IOMMU: use iommu_device_max_index x86: add PCI IDs for AMD Barcelona PCI devices x86/iommu: use __GFP_ZERO instead of memset for GART x86/iommu: convert GART need_flush to bool x86/iommu: make GART driver checkpatch clean x86 gart: remove unnecessary initialization x86: restore old GART alloc_coherent behavior revert "x86: make GART to respect device's dma_mask about virtual mappings" x86: export pci-nommu's alloc_coherent iommu: remove fullflush and nofullflush in IOMMU generic option x86: remove set_bit_string() iommu: export iommu_area_reserve helper function AMD IOMMU: use coherent_dma_mask in alloc_coherent add AMD IOMMU tree to MAINTAINERS file AMD IOMMU: use cmd_buf_size when freeing the command buffer AMD IOMMU: calculate IVHD size with a function AMD IOMMU: remove unnecessary cast to u64 in the init code AMD IOMMU: free domain bitmap with its allocation order AMD IOMMU: simplify dma_mask_to_pages ...
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| | *---. \ \ \ \ \ \ \ \ \ \ \ \ \ Merge branches 'core/iommu', 'x86/amd-iommu' and 'x86/iommu' into ↵Ingo Molnar2008-10-101-0/+2
| | |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ | | | | | |_|_|_|_|_|_|/ / / / / / / | | | | |/| | | | | | | | | | | / / | | | |_|_|_|_|_|_|_|_|_|_|_|_|/ / | | |/| | | | | | | | | | | | | / | | | | |_|_|_|_|_|_|_|_|_|_|_|/ | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | x86-v28-for-linus-phase3-B Conflicts: arch/x86/kernel/pci-gart_64.c include/asm-x86/dma-mapping.h
| | | | | * | | | | | | | | | | Merge branch 'linus' into x86/iommuIngo Molnar2008-09-141-22/+15
| | | | | |\ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: lib/swiotlb.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | | | * \ \ \ \ \ \ \ \ \ \ \ Merge commit 'v2.6.27-rc6' into x86/iommuIngo Molnar2008-09-1033-341/+556
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| | | | | * | | | | | | | | | | | dma-coherent: export dma_[alloc|release]_from_coherent methodsIngo Molnar2008-08-221-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fixes modular builds: ERROR: "dma_alloc_from_coherent" [sound/core/snd-page-alloc.ko] undefined! ERROR: "dma_release_from_coherent" [sound/core/snd-page-alloc.ko] undefined! Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | | | | | | | | | Merge branch 'next' of ↵Linus Torvalds2008-10-111-1/+10
| |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq: [CPUFREQ] Fix BUG: using smp_processor_id() in preemptible code [CPUFREQ] Don't export governors for default governor [CPUFREQ][6/6] cpufreq: Add idle microaccounting in ondemand governor [CPUFREQ][5/6] cpufreq: Changes to get_cpu_idle_time_us(), used by ondemand governor [CPUFREQ][4/6] cpufreq_ondemand: Parameterize down differential [CPUFREQ][3/6] cpufreq: get_cpu_idle_time() changes in ondemand for idle-microaccounting [CPUFREQ][2/6] cpufreq: Change load calculation in ondemand for software coordination [CPUFREQ][1/6] cpufreq: Add cpu number parameter to __cpufreq_driver_getavg() [CPUFREQ] use deferrable delayed work init in conservative governor [CPUFREQ] drivers/cpufreq/cpufreq.c: Adjust error handling code involving cpufreq_cpu_put [CPUFREQ] add error handling for cpufreq_register_governor() error [CPUFREQ] acpi-cpufreq: add error handling for cpufreq_register_driver() error [CPUFREQ] Coding style fixes to arch/x86/kernel/cpu/cpufreq/powernow-k6.c [CPUFREQ] Coding style fixes to arch/x86/kernel/cpu/cpufreq/elanfreq.c
| | * | | | | | | | | | | | | | | | [CPUFREQ][5/6] cpufreq: Changes to get_cpu_idle_time_us(), used by ondemand ↵venkatesh.pallipadi@intel.com2008-10-091-1/+10
| | |/ / / / / / / / / / / / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | governor export get_cpu_idle_time_us() for it to be used in ondemand governor. Last update time can be current time when the CPU is currently non-idle, accounting for the busy time since last idle. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
| * | | | | | | | | | | | | | | | Merge branch 'rcu-v28-for-linus' of ↵Linus Torvalds2008-10-103-95/+257
| |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'rcu-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (21 commits) rcu: RCU-based detection of stalled CPUs for Classic RCU, fix rcu: RCU-based detection of stalled CPUs for Classic RCU rcu: add rcu_read_lock_sched() / rcu_read_unlock_sched() rcu: fix sparse shadowed variable warning doc/RCU: fix pseudocode in rcuref.txt rcuclassic: fix compiler warning rcu: use irq-safe locks rcuclassic: fix compilation NG rcu: fix locking cleanup fallout rcu: remove redundant ACCESS_ONCE definition from rcupreempt.c rcu: fix classic RCU locking cleanup lockdep problem rcu: trace fix possible mem-leak rcu: just rename call_rcu_bh instead of making it a macro rcu: remove list_for_each_rcu() rcu: fixes to include/linux/rcupreempt.h rcu: classic RCU locking and memory-barrier cleanups rcu: prevent console flood when one CPU sees another AWOL via RCU rcu, debug: detect stalled grace periods, cleanups rcu, debug: detect stalled grace periods rcu classic: new algorithm for callbacks-processing(v2) ...
| | * | | | | | | | | | | | | | | | Merge branch 'linus' into core/rcuIngo Molnar2008-10-097-17/+97
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| | * | | | | | | | | | | | | | | | rcu: RCU-based detection of stalled CPUs for Classic RCU, fixIngo Molnar2008-10-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fix the !CONFIG_RCU_CPU_STALL_DETECTOR path: kernel/rcuclassic.c: In function '__rcu_pending': kernel/rcuclassic.c:609: error: too few arguments to function 'check_cpu_stall' Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | rcu: RCU-based detection of stalled CPUs for Classic RCUPaul E. McKenney2008-10-031-80/+86
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds stalled-CPU detection to Classic RCU. This capability is enabled by a new config variable CONFIG_RCU_CPU_STALL_DETECTOR, which defaults disabled. This is a debugging feature to detect infinite loops in kernel code, not something that non-kernel-hackers would be expected to care about. This feature can detect looping CPUs in !PREEMPT builds and looping CPUs with preemption disabled in PREEMPT builds. This is essentially a port of this functionality from the treercu patch, replacing the stall debug patch that is already in tip/core/rcu (commit 67182ae1c4). The changes from the patch in tip/core/rcu include making the config variable name match that in treercu, changing from seconds to jiffies to avoid spurious warnings, and printing a boot message when this feature is enabled. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | Merge commit 'v2.6.27-rc8' into core/rcuIngo Molnar2008-10-0312-51/+97
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| | * | | | | | | | | | | | | | | | | rcu: fix sparse shadowed variable warningHarvey Harrison2008-09-231-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernel/rcuclassic.c:564:18: warning: symbol 'flags' shadows an earlier one kernel/rcuclassic.c:527:16: originally declared here Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | Merge commit 'v2.6.27-rc6' into core/rcuIngo Molnar2008-09-1046-707/+1133
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| | * | | | | | | | | | | | | | | | | rcuclassic: fix compiler warningHiroshi Shimamoto2008-08-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CC kernel/rcuclassic.o kernel/rcuclassic.c: In function 'rcu_init_percpu_data': kernel/rcuclassic.c:705: warning: comparison of distinct pointer types lacks a cast kernel/rcuclassic.c:713: warning: comparison of distinct pointer types lacks a cast flags should be unsigned long. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu: use irq-safe locksPaul E. McKenney2008-08-211-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some earlier tip/core/rcu patches caused RCU to incorrectly enable irqs too early in boot. This caused Yinghai's repeated-kexec testing to hit oopses, presumably due to so that device interrupts left over from the prior kernel instance (which would oops the newly booting kernel before it got a chance to reset said devices). This patch therefore converts all the local_irq_disable()s in rcuclassic.c to local_irq_save(). Besides, I never did like local_irq_disable() anyway. ;-) Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcuclassic: fix compilation NGHiroshi Shimamoto2008-08-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fix: CC kernel/rcuclassic.o kernel/rcuclassic.c: In function '__rcu_process_callbacks': kernel/rcuclassic.c:561: error: 'flags' undeclared (first use in this function) kernel/rcuclassic.c:561: error: (Each undeclared identifier is reported only once kernel/rcuclassic.c:561: error: for each function it appears in.) Declare missing variable flags. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu: fix locking cleanup falloutPaul E. McKenney2008-08-191-14/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Given that the rcp->lock is now acquired from call_rcu(), which can be invoked from irq-disable regions, all acquisitions need to disable irqs. The following patch fixes this. Although I don't have any reason to believe that this is the cause of Yinghai's oops, it does need to be fixed. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu: remove redundant ACCESS_ONCE definition from rcupreempt.cPaul E. McKenney2008-08-181-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the redundant definition of ACCESS_ONCE() from rcupreempt.c in favor of the one in compiler.h. Also merge the comment header from rcupreempt.c's definition into that in compiler.h. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu: fix classic RCU locking cleanup lockdep problemPaul E. McKenney2008-08-171-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Fri, Aug 15, 2008 at 04:24:30PM +0200, Ingo Molnar wrote: > > Paul, > > one of your two recent RCU patches caused this lockdep splat in -tip > testing: > > -------------------> > Brought up 2 CPUs > Total of 2 processors activated (6850.87 BogoMIPS). > PM: Adding info for No Bus:platform > khelper used greatest stack depth: 3124 bytes left > > ================================= > [ INFO: inconsistent lock state ] > 2.6.27-rc3-tip #1 > --------------------------------- > inconsistent {softirq-on-W} -> {in-softirq-W} usage. > ksoftirqd/0/4 [HC0[0]:SC1[1]:HE1:SE0] takes: > (&rcu_ctrlblk.lock){-+..}, at: [<c016d91c>] __rcu_process_callbacks+0x1ac/0x1f0 > {softirq-on-W} state was registered at: > [<c01528e4>] __lock_acquire+0x3f4/0x5b0 > [<c0152b29>] lock_acquire+0x89/0xc0 > [<c076142b>] _spin_lock+0x3b/0x70 > [<c016d649>] rcu_init_percpu_data+0x29/0x80 > [<c075e43f>] rcu_cpu_notify+0xaf/0xd0 > [<c076458d>] notifier_call_chain+0x2d/0x60 > [<c0145ede>] __raw_notifier_call_chain+0x1e/0x30 > [<c075db29>] _cpu_up+0x79/0x110 > [<c075dc0d>] cpu_up+0x4d/0x70 > [<c0a769e1>] kernel_init+0xb1/0x200 > [<c01048a3>] kernel_thread_helper+0x7/0x10 > [<ffffffff>] 0xffffffff > irq event stamp: 14 > hardirqs last enabled at (14): [<c01534db>] trace_hardirqs_on+0xb/0x10 > hardirqs last disabled at (13): [<c014dbeb>] trace_hardirqs_off+0xb/0x10 > softirqs last enabled at (0): [<c012b186>] copy_process+0x276/0x1190 > softirqs last disabled at (11): [<c0105c0a>] call_on_stack+0x1a/0x30 > > other info that might help us debug this: > no locks held by ksoftirqd/0/4. > > stack backtrace: > Pid: 4, comm: ksoftirqd/0 Not tainted 2.6.27-rc3-tip #1 > [<c01504dc>] print_usage_bug+0x16c/0x1b0 > [<c0152455>] mark_lock+0xa75/0xb10 > [<c0108b75>] ? sched_clock+0x15/0x30 > [<c015289d>] __lock_acquire+0x3ad/0x5b0 > [<c0152b29>] lock_acquire+0x89/0xc0 > [<c016d91c>] ? __rcu_process_callbacks+0x1ac/0x1f0 > [<c076142b>] _spin_lock+0x3b/0x70 > [<c016d91c>] ? __rcu_process_callbacks+0x1ac/0x1f0 > [<c016d91c>] __rcu_process_callbacks+0x1ac/0x1f0 > [<c016d986>] rcu_process_callbacks+0x26/0x50 > [<c0132305>] __do_softirq+0x95/0x120 > [<c0132270>] ? __do_softirq+0x0/0x120 > [<c0105c0a>] call_on_stack+0x1a/0x30 > [<c0132426>] ? ksoftirqd+0x96/0x110 > [<c0132390>] ? ksoftirqd+0x0/0x110 > [<c01411f7>] ? kthread+0x47/0x80 > [<c01411b0>] ? kthread+0x0/0x80 > [<c01048a3>] ? kernel_thread_helper+0x7/0x10 > ======================= > calling init_cpufreq_transition_notifier_list+0x0/0x20 > initcall init_cpufreq_transition_notifier_list+0x0/0x20 returned 0 after 0 msecs > calling net_ns_init+0x0/0x190 > net_namespace: 676 bytes > initcall net_ns_init+0x0/0x190 returned 0 after 0 msecs > calling cpufreq_tsc+0x0/0x20 > initcall cpufreq_tsc+0x0/0x20 returned 0 after 0 msecs > calling reboot_init+0x0/0x20 > initcall reboot_init+0x0/0x20 returned 0 after 0 msecs > calling print_banner+0x0/0x10 > Booting paravirtualized kernel on bare hardware > > <----------------------- > > my guess is on: > > commit 1f7b94cd3d564901f9e04a8bc5832ae7bfd690a0 > Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > Date: Tue Aug 5 09:21:44 2008 -0700 > > rcu: classic RCU locking and memory-barrier cleanups > > Ingo Fixes a problem detected by lockdep in which rcu->lock was acquired both in irq context and in process context, but without disabling from process context. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu: trace fix possible mem-leakSteven Rostedt2008-08-151-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the initialization of the RCU trace module, if rcupreempt_debugfs_init() fails, we never free the the trace buffer. This patch frees the trace buffer in case the debugfs fails. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Reviewed-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu: classic RCU locking and memory-barrier cleanupsPaul E. McKenney2008-08-151-10/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch simplifies the locking and memory-barrier usage in the Classic RCU grace-period-detection mechanism, incorporating Lai Jiangshan's feedback from the earlier version (http://lkml.org/lkml/2008/8/1/400 and http://lkml.org/lkml/2008/8/3/43). Passed 10 hours of rcutorture concurrent with CPUs being put online and taken offline on a 128-hardware-thread Power machine. My apologies to whoever in the Eastern Hemisphere was planning to use this machine over the Western Hemisphere night, but it was sitting idle and... So this is ready for tip/core/rcu. This patch is in preparation for moving to a hierarchical algorithm to allow the very large SMP machines -- requested by some people at OLS, and there seem to have been a few recent patches in the 4096-CPU direction as well. The general idea is to move to a much more conservative concurrency design, then apply a hierarchy to reduce contention on the global lock by a few orders of magnitude (larger machines would see greater reductions). The reason for taking a conservative approach is that this code isn't on any fast path. Prototype in progress. This patch is against the linux-tip git tree (tip/core/rcu). If you wish to test this against 2.6.26, use the following set of patches: http://www.rdrop.com/users/paulmck/patches/2.6.26-ljsimp-1.patch http://www.rdrop.com/users/paulmck/patches/2.6.26-ljsimpfix-3.patch The first patch combines commits 5127bed588a2f8f3a1f732de2a8a190b7df5dce3 and 3cac97cbb14aed00d83eb33d4613b0fe3aaea863 from Lai Jiangshan <laijs@cn.fujitsu.com>, and the second patch contains my changes. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu: prevent console flood when one CPU sees another AWOL via RCUPaul E. McKenney2008-08-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | One small change needed to keep from flooding the console when one CPU notices that another is AWOL. Unless I am missing something subtle. Otherwise the cleanups look good! Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu, debug: detect stalled grace periods, cleanupsIngo Molnar2008-08-111-13/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | small cleanups. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | | | | | | | | | | | rcu, debug: detect stalled grace periodsPaul E. McKenney2008-08-111-0/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | this is a diagnostic patch for Classic RCU. The approach is to record a timestamp at the beginning of the grace period (in rcu_start_batch()), then have rcu_check_callbacks() complain if: 1. it is running on a CPU that has holding up grace periods for a long time (say one second). This will identify the culprit assuming that the culprit has not disabled hardware irqs, instruction execution, or some such. 2. it is running on a CPU that is not holding up grace periods, but grace periods have been held up for an even longer time (say two seconds). It is enabled via the default-off CONFIG_DEBUG_RCU_STALL kernel parameter. Rather than exponential backoff, it backs off to once per 30 seconds. My feeling upon thinking on it was that if you have stalled RCU grace periods for that long, a few extra printk() messages are probably the least of your worries... Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: David Witbrodt <dawitbro@sbcglobal.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>