user/sven/linux.git/Documentation/kernel-parameters.txt, branch v3.8

rcu: Make rcu_nocb_poll an early_param instead of module_param

2013-01-08T22:12:19Z

The as-documented rcu_nocb_poll will fail to enable this feature for two reasons. (1) there is an extra "s" in the documented name which is not in the code, and (2) since it uses module_param, it really is expecting a prefix, akin to "rcutree.fanout_leaf" and the prefix isn't documented. However, there are several reasons why we might not want to simply fix the typo and add the prefix: 1) we'd end up with rcutree.rcu_nocb_poll, and rather probably make a change to rcutree.nocb_poll 2) if we did #1, then the prefix wouldn't be consistent with the rcu_nocbs= parameter (i.e. one with, one without prefix) 3) the use of module_param in a header file is less than desired, since it isn't immediately obvious that it will get processed via rcutree.c and get the prefix from that (although use of module_param_named() could clarify that.) 4) the implied export of /sys/module/rcutree/parameters/rcu_nocb_poll data to userspace via module_param() doesn't really buy us anything, as it is read-only and we can tell if it is enabled already without it, since there is a printk at early boot telling us so. In light of all that, just change it from a module_param() to an early_setup() call, and worry about adding it to /sys later on if we decide to allow a dynamic setting of it. Also change the variable to be tagged as read_mostly, since it will only ever be fiddled with at most, once at boot. Signed-off-by: Paul Gortmaker Signed-off-by: Paul E. McKenney

Documentation: kernel-parameters.txt remove capability.disable

2012-12-21T01:40:19Z

Remove the documentation for capability.disable. The code supporting this parameter was removed with commit 5915eb53861c ("security: remove dummy module") Signed-off-by: Josh Boyer Acked-by: Serge Hallyn Cc: Rob Landley Cc: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Documentation/kernel-parameters.txt: update mem= option's spec according to its implementation

2012-12-18T01:15:12Z

Current mem= implementation seems buggy because the specification and implementation don't match. The current mem= has been working for many years and it's not buggy - it works as expected. So we should update the specification. Signed-off-by: Wen Congyang Cc: Rob Landley Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'balancenuma-v11' of git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux-balancenuma

2012-12-16T23:18:08Z

Pull Automatic NUMA Balancing bare-bones from Mel Gorman: "There are three implementations for NUMA balancing, this tree (balancenuma), numacore which has been developed in tip/master and autonuma which is in aa.git. In almost all respects balancenuma is the dumbest of the three because its main impact is on the VM side with no attempt to be smart about scheduling. In the interest of getting the ball rolling, it would be desirable to see this much merged for 3.8 with the view to building scheduler smarts on top and adapting the VM where required for 3.9. The most recent set of comparisons available from different people are mel: https://lkml.org/lkml/2012/12/9/108 mingo: https://lkml.org/lkml/2012/12/7/331 tglx: https://lkml.org/lkml/2012/12/10/437 srikar: https://lkml.org/lkml/2012/12/10/397 The results are a mixed bag. In my own tests, balancenuma does reasonably well. It's dumb as rocks and does not regress against mainline. On the other hand, Ingo's tests shows that balancenuma is incapable of converging for this workloads driven by perf which is bad but is potentially explained by the lack of scheduler smarts. Thomas' results show balancenuma improves on mainline but falls far short of numacore or autonuma. Srikar's results indicate we all suffer on a large machine with imbalanced node sizes. My own testing showed that recent numacore results have improved dramatically, particularly in the last week but not universally. We've butted heads heavily on system CPU usage and high levels of migration even when it shows that overall performance is better. There are also cases where it regresses. Of interest is that for specjbb in some configurations it will regress for lower numbers of warehouses and show gains for higher numbers which is not reported by the tool by default and sometimes missed in treports. Recently I reported for numacore that the JVM was crashing with NullPointerExceptions but currently it's unclear what the source of this problem is. Initially I thought it was in how numacore batch handles PTEs but I'm no longer think this is the case. It's possible numacore is just able to trigger it due to higher rates of migration. These reports were quite late in the cycle so I/we would like to start with this tree as it contains much of the code we can agree on and has not changed significantly over the last 2-3 weeks." * tag 'balancenuma-v11' of git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux-balancenuma: (50 commits) mm/rmap, migration: Make rmap_walk_anon() and try_to_unmap_anon() more scalable mm/rmap: Convert the struct anon_vma::mutex to an rwsem mm: migrate: Account a transhuge page properly when rate limiting mm: numa: Account for failed allocations and isolations as migration failures mm: numa: Add THP migration for the NUMA working set scanning fault case build fix mm: numa: Add THP migration for the NUMA working set scanning fault case. mm: sched: numa: Delay PTE scanning until a task is scheduled on a new node mm: sched: numa: Control enabling and disabling of NUMA balancing if !SCHED_DEBUG mm: sched: numa: Control enabling and disabling of NUMA balancing mm: sched: Adapt the scanning rate if a NUMA hinting fault does not migrate mm: numa: Use a two-stage filter to restrict pages being migrated for unlikely task<->node relationships mm: numa: migrate: Set last_nid on newly allocated page mm: numa: split_huge_page: Transfer last_nid on tail page mm: numa: Introduce last_nid to the page frame sched: numa: Slowly increase the scanning period as NUMA faults are handled mm: numa: Rate limit setting of pte_numa if node is saturated mm: numa: Rate limit the amount of memory that is migrated between nodes mm: numa: Structures for Migrate On Fault per NUMA migration rate limiting mm: numa: Migrate pages handled during a pmd_numa hinting fault mm: numa: Migrate on reference policy ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2012-12-13T02:07:07Z

Pull networking changes from David Miller: 1) Allow to dump, monitor, and change the bridge multicast database using netlink. From Cong Wang. 2) RFC 5961 TCP blind data injection attack mitigation, from Eric Dumazet. 3) Networking user namespace support from Eric W. Biederman. 4) tuntap/virtio-net multiqueue support by Jason Wang. 5) Support for checksum offload of encapsulated packets (basically, tunneled traffic can still be checksummed by HW). From Joseph Gasparakis. 6) Allow BPF filter access to VLAN tags, from Eric Dumazet and Daniel Borkmann. 7) Bridge port parameters over netlink and BPDU blocking support from Stephen Hemminger. 8) Improve data access patterns during inet socket demux by rearranging socket layout, from Eric Dumazet. 9) TIPC protocol updates and cleanups from Ying Xue, Paul Gortmaker, and Jon Maloy. 10) Update TCP socket hash sizing to be more in line with current day realities. The existing heurstics were choosen a decade ago. From Eric Dumazet. 11) Fix races, queue bloat, and excessive wakeups in ATM and associated drivers, from Krzysztof Mazur and David Woodhouse. 12) Support DOVE (Distributed Overlay Virtual Ethernet) extensions in VXLAN driver, from David Stevens. 13) Add "oops_only" mode to netconsole, from Amerigo Wang. 14) Support set and query of VEB/VEPA bridge mode via PF_BRIDGE, also allow DCB netlink to work on namespaces other than the initial namespace. From John Fastabend. 15) Support PTP in the Tigon3 driver, from Matt Carlson. 16) tun/vhost zero copy fixes and improvements, plus turn it on by default, from Michael S. Tsirkin. 17) Support per-association statistics in SCTP, from Michele Baldessari. And many, many, driver updates, cleanups, and improvements. Too numerous to mention individually. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits) net/mlx4_en: Add support for destination MAC in steering rules net/mlx4_en: Use generic etherdevice.h functions. net: ethtool: Add destination MAC address to flow steering API bridge: add support of adding and deleting mdb entries bridge: notify mdb changes via netlink ndisc: Unexport ndisc_{build,send}_skb(). uapi: add missing netconf.h to export list pkt_sched: avoid requeues if possible solos-pci: fix double-free of TX skb in DMA mode bnx2: Fix accidental reversions. bna: Driver Version Updated to 3.1.2.1 bna: Firmware update bna: Add RX State bna: Rx Page Based Allocation bna: TX Intr Coalescing Fix bna: Tx and Rx Optimizations bna: Code Cleanup and Enhancements ath9k: check pdata variable before dereferencing it ath5k: RX timestamp is reported at end of frame ath9k_htc: RX timestamp is reported at end of frame ...

Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-12-12T04:01:33Z

Pull x86 timer update from Ingo Molnar: "This tree includes HPET fixes and also implements a calibration-free, TSC match driven APIC timer interrupt mode: 'TSC deadline mode' supported in SandyBridge and later CPUs." * 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: hpet: Fix inverted return value check in arch_setup_hpet_msi() x86: hpet: Fix masking of MSI interrupts x86: apic: Use tsc deadline for oneshot when available

Merge branch 'x86-bsp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-12-12T03:56:33Z

Pull x86 BSP hotplug changes from Ingo Molnar: "This tree enables CPU#0 (the boot processor) to be onlined/offlined on x86, just like any other CPU. Enabled on Intel CPUs for now. Allowing this required the identification and fixing of latent CPU#0 assumptions (such as CPU#0 initializations, etc.) in the x86 architecture code, plus the identification of barriers to BSP-offlining, such as active PIC interrupts which can only be serviced on the BSP. It's behind a default-off option, and there's a debug option that allows the automatic testing of this feature. The motivation of this feature is to allow and prepare for true CPU-hotplug hardware support: recent changes to MCE support enable us to detect a deteriorating but not yet hard-failing L1/L2 cache on a CPU that could be soft-unplugged - or a failing L3 cache on a multi-socket system. Note that true hardware hot-plug is not yet fully enabled by this, because that requires a special platform wakeup sequence to be sent to the freshly powered up CPU#0. Future patches for this are planned, once such a platform exists. Chicken and egg" * 'x86-bsp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, topology: Debug CPU0 hotplug x86/i387.c: Initialize thread xstate only on CPU0 only once x86, hotplug: Handle retrigger irq by the first available CPU x86, hotplug: The first online processor saves the MTRR state x86, hotplug: During CPU0 online, enable x2apic, set_numa_node. x86, hotplug: Wake up CPU0 via NMI instead of INIT, SIPI, SIPI x86-32, hotplug: Add start_cpu0() entry point to head_32.S x86-64, hotplug: Add start_cpu0() entry point to head_64.S kernel/cpu.c: Add comment for priority in cpu_hotplug_pm_callback x86, hotplug, suspend: Online CPU0 for suspend or hibernate x86, hotplug: Support functions for CPU0 online/offline x86, topology: Don't offline CPU0 if any PIC irq can not be migrated out of it x86, Kconfig: Add config switch for CPU0 hotplug doc: Add x86 CPU0 online/offline feature

Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-12-12T02:14:31Z

Pull perf updates from Ingo Molnar: "Lots of activity: 211 files changed, 8328 insertions(+), 4116 deletions(-) most of it on the tooling side. Main changes: * ftrace enhancements and fixes from Steve Rostedt. * uprobes fixes, cleanups and preparation for the ARM port from Oleg Nesterov. * UAPI fixes, from David Howels - prepares the arch/x86 UAPI transition * Separate perf tests into multiple objects, one per test, from Jiri Olsa. * Make hardware event translations available in sysfs, from Jiri Olsa. * Fixes to /proc/pid/maps parsing, preparatory to supporting data maps, from Namhyung Kim * Implement ui_progress for GTK, from Namhyung Kim * Add framework for automated perf_event_attr tests, where tools with different command line options will be run from a 'perf test', via python glue, and the perf syscall will be intercepted to verify that the perf_event_attr fields set by the tool are those expected, from Jiri Olsa * Add a 'link' method for hists, so that we can have the leader with buckets for all the entries in all the hists. This new method is now used in the default 'diff' output, making the sum of the 'baseline' column be 100%, eliminating blind spots. * libtraceevent fixes for compiler warnings trying to make perf it build on some distros, like fedora 14, 32-bit, some of the warnings really pointed to real bugs. * Add a browser for 'perf script' and make it available from the report and annotate browsers. It does filtering to find the scripts that handle events found in the perf.data file used. From Feng Tang * perf inject changes to allow showing where a task sleeps, from Andrew Vagin. * Makefile improvements from Namhyung Kim. * Add --pre and --post command hooks in 'stat', from Peter Zijlstra. * Don't stop synthesizing threads when one vanishes, this is for the existing threads when we start a tool like trace. * Use sched:sched_stat_runtime to provide a thread summary, this produces the same output as the 'trace summary' subcommand of tglx's original "trace" tool. * Support interrupted syscalls in 'trace' * Add an event duration column and filter in 'trace'. * There are references to the man pages in some tools, so try to build Documentation when installing, warning the user if that is not possible, from Borislav Petkov. * Give user better message if precise is not supported, from David Ahern. * Try to find cross-built objdump path by using the session environment information in the perf.data file header, from Irina Tirdea, original patch and idea by Namhyung Kim. * Diplays more output on features check for make V=1, so that one can figure out what is happening by looking at gcc output, etc. From Jiri Olsa. * Add on_exit implementation for systems without one, e.g. Android, from Bernhard Rosenkraenzer. * Only process events for vcpus of interest, helps handling large number of events, from David Ahern. * Cross compilation fixes for Android, from Irina Tirdea. * Add documentation on compiling for Android, from Irina Tirdea. * perf diff improvements from Jiri Olsa. * Target (task/user/cpu/syswide) handling improvements, from Namhyung Kim. * Add support in 'trace' for tracing workload given by command line, from Namhyung Kim. * ... and much more." * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (194 commits) uprobes: Use percpu_rw_semaphore to fix register/unregister vs dup_mmap() race perf evsel: Introduce is_group_member method perf powerpc: Use uapi/unistd.h to fix build error tools: Pass the target in descend tools: Honour the O= flag when tool build called from a higher Makefile tools: Define a Makefile function to do subdir processing perf ui: Always compile browser setup code perf ui: Add ui_progress__finish() perf ui gtk: Implement ui_progress functions perf ui: Introduce generic ui_progress helper perf ui tui: Move progress.c under ui/tui directory perf tools: Add basic event modifier sanity check perf tools: Omit group members from perf_evlist__disable/enable perf tools: Ensure single disable call per event in record comand perf tools: Fix 'disabled' attribute config for record command perf tools: Fix attributes for '{}' defined event groups perf tools: Use sscanf for parsing /proc/pid/maps perf tools: Add gtk. config option for launching GTK browser perf tools: Fix compile error on NO_NEWT=1 build perf hists: Initialize all of he->stat with zeroes ...

mm: sched: numa: Control enabling and disabling of NUMA balancing

2012-12-11T14:42:55Z

This patch adds Kconfig options and kernel parameters to allow the enabling and disabling of automatic NUMA balancing. The existance of such a switch was and is very important when debugging problems related to transparent hugepages and we should have the same for automatic NUMA placement. Signed-off-by: Mel Gorman

rcu: Add callback-free CPUs

2012-11-16T18:05:56Z

RCU callback execution can add significant OS jitter and also can degrade both scheduling latency and, in asymmetric multiprocessors, energy efficiency. This commit therefore adds the ability for selected CPUs ("rcu_nocbs=" boot parameter) to have their callbacks offloaded to kthreads. If the "rcu_nocb_poll" boot parameter is also specified, these kthreads will do polling, removing the need for the offloaded CPUs to do wakeups. At least one CPU must be doing normal callback processing: currently CPU 0 cannot be selected as a no-CBs CPU. In addition, attempts to offline the last normal-CBs CPU will fail. This feature was inspired by Jim Houston's and Joe Korty's JRCU, and this commit includes fixes to problems located by Fengguang Wu's kbuild test robot. [ paulmck: Added gfp.h include file as suggested by Fengguang Wu. ] Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney