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2012-10-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking changes from David Miller: 1) GRE now works over ipv6, from Dmitry Kozlov. 2) Make SCTP more network namespace aware, from Eric Biederman. 3) TEAM driver now works with non-ethernet devices, from Jiri Pirko. 4) Make openvswitch network namespace aware, from Pravin B Shelar. 5) IPV6 NAT implementation, from Patrick McHardy. 6) Server side support for TCP Fast Open, from Jerry Chu and others. 7) Packet BPF filter supports MOD and XOR, from Eric Dumazet and Daniel Borkmann. 8) Increate the loopback default MTU to 64K, from Eric Dumazet. 9) Use a per-task rather than per-socket page fragment allocator for outgoing networking traffic. This benefits processes that have very many mostly idle sockets, which is quite common. From Eric Dumazet. 10) Use up to 32K for page fragment allocations, with fallbacks to smaller sizes when higher order page allocations fail. Benefits are a) less segments for driver to process b) less calls to page allocator c) less waste of space. From Eric Dumazet. 11) Allow GRO to be used on GRE tunnels, from Eric Dumazet. 12) VXLAN device driver, one way to handle VLAN issues such as the limitation of 4096 VLAN IDs yet still have some level of isolation. From Stephen Hemminger. 13) As usual there is a large boatload of driver changes, with the scale perhaps tilted towards the wireless side this time around. Fix up various fairly trivial conflicts, mostly caused by the user namespace changes. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1012 commits) hyperv: Add buffer for extended info after the RNDIS response message. hyperv: Report actual status in receive completion packet hyperv: Remove extra allocated space for recv_pkt_list elements hyperv: Fix page buffer handling in rndis_filter_send_request() hyperv: Fix the missing return value in rndis_filter_set_packet_filter() hyperv: Fix the max_xfer_size in RNDIS initialization vxlan: put UDP socket in correct namespace vxlan: Depend on CONFIG_INET sfc: Fix the reported priorities of different filter types sfc: Remove EFX_FILTER_FLAG_RX_OVERRIDE_IP sfc: Fix loopback self-test with separate_tx_channels=1 sfc: Fix MCDI structure field lookup sfc: Add parentheses around use of bitfield macro arguments sfc: Fix null function pointer in efx_sriov_channel_type vxlan: virtual extensible lan igmp: export symbol ip_mc_leave_group netlink: add attributes to fdb interface tg3: unconditionally select HWMON support when tg3 is enabled. Revert "net: ti cpsw ethernet: allow reading phy interface mode from DT" gre: fix sparse warning ...
2012-10-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace changes from Eric Biederman: "This is a mostly modest set of changes to enable basic user namespace support. This allows the code to code to compile with user namespaces enabled and removes the assumption there is only the initial user namespace. Everything is converted except for the most complex of the filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs, nfs, ocfs2 and xfs as those patches need a bit more review. The strategy is to push kuid_t and kgid_t values are far down into subsystems and filesystems as reasonable. Leaving the make_kuid and from_kuid operations to happen at the edge of userspace, as the values come off the disk, and as the values come in from the network. Letting compile type incompatible compile errors (present when user namespaces are enabled) guide me to find the issues. The most tricky areas have been the places where we had an implicit union of uid and gid values and were storing them in an unsigned int. Those places were converted into explicit unions. I made certain to handle those places with simple trivial patches. Out of that work I discovered we have generic interfaces for storing quota by projid. I had never heard of the project identifiers before. Adding full user namespace support for project identifiers accounts for most of the code size growth in my git tree. Ultimately there will be work to relax privlige checks from "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing root in a user names to do those things that today we only forbid to non-root users because it will confuse suid root applications. While I was pushing kuid_t and kgid_t changes deep into the audit code I made a few other cleanups. I capitalized on the fact we process netlink messages in the context of the message sender. I removed usage of NETLINK_CRED, and started directly using current->tty. Some of these patches have also made it into maintainer trees, with no problems from identical code from different trees showing up in linux-next. After reading through all of this code I feel like I might be able to win a game of kernel trivial pursuit." Fix up some fairly trivial conflicts in netfilter uid/git logging code. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits) userns: Convert the ufs filesystem to use kuid/kgid where appropriate userns: Convert the udf filesystem to use kuid/kgid where appropriate userns: Convert ubifs to use kuid/kgid userns: Convert squashfs to use kuid/kgid where appropriate userns: Convert reiserfs to use kuid and kgid where appropriate userns: Convert jfs to use kuid/kgid where appropriate userns: Convert jffs2 to use kuid and kgid where appropriate userns: Convert hpfs to use kuid and kgid where appropriate userns: Convert btrfs to use kuid/kgid where appropriate userns: Convert bfs to use kuid/kgid where appropriate userns: Convert affs to use kuid/kgid wherwe appropriate userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids userns: On ia64 deal with current_uid and current_gid being kuid and kgid userns: On ppc convert current_uid from a kuid before printing. userns: Convert s390 getting uid and gid system calls to use kuid and kgid userns: Convert s390 hypfs to use kuid and kgid where appropriate userns: Convert binder ipc to use kuids userns: Teach security_path_chown to take kuids and kgids userns: Add user namespace support to IMA userns: Convert EVM to deal with kuids and kgids in it's hmac computation ...
2012-10-02Merge branch 'for-3.7-hierarchy' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup hierarchy update from Tejun Heo: "Currently, different cgroup subsystems handle nested cgroups completely differently. There's no consistency among subsystems and the behaviors often are outright broken. People at least seem to agree that the broken hierarhcy behaviors need to be weeded out if any progress is gonna be made on this front and that the fallouts from deprecating the broken behaviors should be acceptable especially given that the current behaviors don't make much sense when nested. This patch makes cgroup emit warning messages if cgroups for subsystems with broken hierarchy behavior are nested to prepare for fixing them in the future. This was put in a separate branch because more related changes were expected (didn't make it this round) and the memory cgroup wanted to pull in this and make changes on top." * 'for-3.7-hierarchy' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: mark subsystems with broken hierarchy support and whine if cgroups are nested for them
2012-10-02Merge branch 'for-3.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - xattr support added. The implementation is shared with tmpfs. The usage is restricted and intended to be used to manage per-cgroup metadata by system software. tmpfs changes are routed through this branch with Hugh's permission. - cgroup subsystem ID handling simplified. * 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: Define CGROUP_SUBSYS_COUNT according the configuration cgroup: Assign subsystem IDs during compile time cgroup: Do not depend on a given order when populating the subsys array cgroup: Wrap subsystem selection macro cgroup: Remove CGROUP_BUILTIN_SUBSYS_COUNT cgroup: net_prio: Do not define task_netpioidx() when not selected cgroup: net_cls: Do not define task_cls_classid() when not selected cgroup: net_cls: Move sock_update_classid() declaration to cls_cgroup.h cgroup: trivial fixes for Documentation/cgroups/cgroups.txt xattr: mark variable as uninitialized to make both gcc and smatch happy fs: add missing documentation to simple_xattr functions cgroup: add documentation on extended attributes usage cgroup: rename subsys_bits to subsys_mask cgroup: add xattr support cgroup: revise how we re-populate root directory xattr: extract simple_xattr code from tmpfs
2012-10-02Merge branch 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds
Pull workqueue changes from Tejun Heo: "This is workqueue updates for v3.7-rc1. A lot of activities this round including considerable API and behavior cleanups. * delayed_work combines a timer and a work item. The handling of the timer part has always been a bit clunky leading to confusing cancelation API with weird corner-case behaviors. delayed_work is updated to use new IRQ safe timer and cancelation now works as expected. * Another deficiency of delayed_work was lack of the counterpart of mod_timer() which led to cancel+queue combinations or open-coded timer+work usages. mod_delayed_work[_on]() are added. These two delayed_work changes make delayed_work provide interface and behave like timer which is executed with process context. * A work item could be executed concurrently on multiple CPUs, which is rather unintuitive and made flush_work() behavior confusing and half-broken under certain circumstances. This problem doesn't exist for non-reentrant workqueues. While non-reentrancy check isn't free, the overhead is incurred only when a work item bounces across different CPUs and even in simulated pathological scenario the overhead isn't too high. All workqueues are made non-reentrant. This removes the distinction between flush_[delayed_]work() and flush_[delayed_]_work_sync(). The former is now as strong as the latter and the specified work item is guaranteed to have finished execution of any previous queueing on return. * In addition to the various bug fixes, Lai redid and simplified CPU hotplug handling significantly. * Joonsoo introduced system_highpri_wq and used it during CPU hotplug. There are two merge commits - one to pull in IRQ safe timer from tip/timers/core and the other to pull in CPU hotplug fixes from wq/for-3.6-fixes as Lai's hotplug restructuring depended on them." Fixed a number of trivial conflicts, but the more interesting conflicts were silent ones where the deprecated interfaces had been used by new code in the merge window, and thus didn't cause any real data conflicts. Tejun pointed out a few of them, I fixed a couple more. * 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (46 commits) workqueue: remove spurious WARN_ON_ONCE(in_irq()) from try_to_grab_pending() workqueue: use cwq_set_max_active() helper for workqueue_set_max_active() workqueue: introduce cwq_set_max_active() helper for thaw_workqueues() workqueue: remove @delayed from cwq_dec_nr_in_flight() workqueue: fix possible stall on try_to_grab_pending() of a delayed work item workqueue: use hotcpu_notifier() for workqueue_cpu_down_callback() workqueue: use __cpuinit instead of __devinit for cpu callbacks workqueue: rename manager_mutex to assoc_mutex workqueue: WORKER_REBIND is no longer necessary for idle rebinding workqueue: WORKER_REBIND is no longer necessary for busy rebinding workqueue: reimplement idle worker rebinding workqueue: deprecate __cancel_delayed_work() workqueue: reimplement cancel_delayed_work() using try_to_grab_pending() workqueue: use mod_delayed_work() instead of __cancel + queue workqueue: use irqsafe timer for delayed_work workqueue: clean up delayed_work initializers and add missing one workqueue: make deferrable delayed_work initializer names consistent workqueue: cosmetic whitespace updates for macro definitions workqueue: deprecate system_nrt[_freezable]_wq workqueue: deprecate flush[_delayed]_work_sync() ...
2012-10-01Merge tag 'tty-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/ttyLinus Torvalds
Pull TTY changes from Greg Kroah-Hartman: "As we skipped the merge window for 3.6-rc1 for the tty tree, everything is now settled down and working properly, so we are ready for 3.7-rc1. Here's the patchset, it's big, but the large changes are removing a firmware file and adding a staging tty driver (it depended on the tty core changes, so it's going through this tree instead of the staging tree.) All of these patches have been in the linux-next tree for a while. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" Fix up more-or-less trivial conflicts in - drivers/char/pcmcia/synclink_cs.c: tty NULL dereference fix vs tty_port_cts_enabled() helper function - drivers/staging/{Kconfig,Makefile}: add-add conflict (dgrp driver added close to other staging drivers) - drivers/staging/ipack/devices/ipoctal.c: "split ipoctal_channel from iopctal" vs "TTY: use tty_port_register_device" * tag 'tty-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (235 commits) tty/serial: Add kgdb_nmi driver tty/serial/amba-pl011: Quiesce interrupts in poll_get_char tty/serial/amba-pl011: Implement poll_init callback tty/serial/core: Introduce poll_init callback kdb: Turn KGDB_KDB=n stubs into static inlines kdb: Implement disable_nmi command kernel/debug: Mask KGDB NMI upon entry serial: pl011: handle corruption at high clock speeds serial: sccnxp: Make 'default' choice in switch last serial: sccnxp: Remove mask termios caps for SW flow control serial: sccnxp: Report actual baudrate back to core serial: samsung: Add poll_get_char & poll_put_char Powerpc 8xx CPM_UART setting MAXIDL register proportionaly to baud rate Powerpc 8xx CPM_UART maxidl should not depend on fifo size Powerpc 8xx CPM_UART too many interrupts Powerpc 8xx CPM_UART desynchronisation serial: set correct baud_base for EXSYS EX-41092 Dual 16950 serial: omap: fix the reciever line error case 8250: blacklist Winbond CIR port 8250_pnp: do pnp probe before legacy probe ...
2012-10-01Merge tag 'arm64-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64 Pull arm64 support from Catalin Marinas: "Linux support for the 64-bit ARM architecture (AArch64) Features currently supported: - 39-bit address space for user and kernel (each) - 4KB and 64KB page configurations - Compat (32-bit) user applications (ARMv7, EABI only) - Flattened Device Tree (mandated for all AArch64 platforms) - ARM generic timers" * tag 'arm64-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64: (35 commits) arm64: ptrace: remove obsolete ptrace request numbers from user headers arm64: Do not set the SMP/nAMP processor bit arm64: MAINTAINERS update arm64: Build infrastructure arm64: Miscellaneous header files arm64: Generic timers support arm64: Loadable modules arm64: Miscellaneous library functions arm64: Performance counters support arm64: Add support for /proc/sys/debug/exception-trace arm64: Debugging support arm64: Floating point and SIMD arm64: 32-bit (compat) applications support arm64: User access library functions arm64: Signal handling support arm64: VDSO support arm64: System calls handling arm64: ELF definitions arm64: SMP support arm64: DMA mapping API ...
2012-10-01Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/asm changes from Ingo Molnar: "The one change that stands out is the alternatives patching change that prevents us from ever patching back instructions from SMP to UP: this simplifies things and speeds up CPU hotplug. Other than that it's smaller fixes, cleanups and improvements." * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Unspaghettize do_trap() x86_64: Work around old GAS bug x86: Use REP BSF unconditionally x86: Prefer TZCNT over BFS x86/64: Adjust types of temporaries used by ffs()/fls()/fls64() x86: Drop unnecessary kernel_eflags variable on 64-bit x86/smp: Don't ever patch back to UP if we unplug cpus
2012-10-01Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer changes from Ingo Molnar: "Timer enhancements, generalizations and cleanups from Tejun Heo, in preparation for workqueue facility enhancements." * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timer: Implement TIMER_IRQSAFE timer: Clean up timer initializers timer: Relocate declarations of init_timer_on_stack_key() timer: Generalize timer->base flags handling
2012-10-01Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "Continued quest to clean up and enhance the cputime code by Frederic Weisbecker, in preparation for future tickless kernel features. Other than that, smallish changes." Fix up trivial conflicts due to additions next to each other in arch/{x86/}Kconfig * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) cputime: Make finegrained irqtime accounting generally available cputime: Gather time/stats accounting config options into a single menu ia64: Reuse system and user vtime accounting functions on task switch ia64: Consolidate user vtime accounting vtime: Consolidate system/idle context detection cputime: Use a proper subsystem naming for vtime related APIs sched: cpu_power: enable ARCH_POWER sched/nohz: Clean up select_nohz_load_balancer() sched: Fix load avg vs. cpu-hotplug sched: Remove __ARCH_WANT_INTERRUPTS_ON_CTXSW sched: Fix nohz_idle_balance() sched: Remove useless code in yield_to() sched: Add time unit suffix to sched sysctl knobs sched/debug: Limit sd->*_idx range on sysctl sched: Remove AFFINE_WAKEUPS feature flag s390: Remove leftover account_tick_vtime() header cputime: Consolidate vtime handling on context switch sched: Move cputime code to its own file cputime: Generalize CONFIG_VIRT_CPU_ACCOUNTING tile: Remove SD_PREFER_LOCAL leftover ...
2012-10-01Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf update from Ingo Molnar: "Lots of changes in this cycle as well, with hundreds of commits from over 30 contributors. Most of the activity was on the tooling side. Higher level changes: - New 'perf kvm' analysis tool, from Xiao Guangrong. - New 'perf trace' system-wide tracing tool - uprobes fixes + cleanups from Oleg Nesterov. - Lots of patches to make perf build on Android out of box, from Irina Tirdea - Extend ftrace function tracing utility to be more dynamic for its users. It allows for data passing to the callback functions, as well as reading regs as if a breakpoint were to trigger at function entry. The main goal of this patch series was to allow kprobes to use ftrace as an optimized probe point when a probe is placed on an ftrace nop. With lots of help from Masami Hiramatsu, and going through lots of iterations, we finally came up with a good solution. - Add cpumask for uncore pmu, use it in 'stat', from Yan, Zheng. - Various tracing updates from Steve Rostedt - Clean up and improve 'perf sched' performance by elliminating lots of needless calls to libtraceevent. - Event group parsing support, from Jiri Olsa - UI/gtk refactorings and improvements from Namhyung Kim - Add support for non-tracepoint events in perf script python, from Feng Tang - Add --symbols to 'script', similar to the one in 'report', from Feng Tang. Infrastructure enhancements and fixes: - Convert the trace builtins to use the growing evsel/evlist tracepoint infrastructure, removing several open coded constructs like switch like series of strcmp to dispatch events, etc. Basically what had already been showcased in 'perf sched'. - Add evsel constructor for tracepoints, that uses libtraceevent just to parse the /format events file, use it in a new 'perf test' to make sure the libtraceevent format parsing regressions can be more readily caught. - Some strange errors were happening in some builds, but not on the next, reported by several people, problem was some parser related files, generated during the build, didn't had proper make deps, fix from Eric Sandeen. - Introduce struct and cache information about the environment where a perf.data file was captured, from Namhyung Kim. - Fix handling of unresolved samples when --symbols is used in 'report', from Feng Tang. - Add union member access support to 'probe', from Hyeoncheol Lee. - Fixups to die() removal, from Namhyung Kim. - Render fixes for the TUI, from Namhyung Kim. - Don't enable annotation in non symbolic view, from Namhyung Kim. - Fix pipe mode in 'report', from Namhyung Kim. - Move related stats code from stat to util/, will be used by the 'stat' kvm tool, from Xiao Guangrong. - Remove die()/exit() calls from several tools. - Resolve vdso callchains, from Jiri Olsa - Don't pass const char pointers to basename, so that we can unconditionally use libgen.h and thus avoid ifdef BIONIC lines, from David Ahern - Refactor hist formatting so that it can be reused with the GTK browser, From Namhyung Kim - Fix build for another rbtree.c change, from Adrian Hunter. - Make 'perf diff' command work with evsel hists, from Jiri Olsa. - Use the only field_sep var that is set up: symbol_conf.field_sep, fix from Jiri Olsa. - .gitignore compiled python binaries, from Namhyung Kim. - Get rid of die() in more libtraceevent places, from Namhyung Kim. - Rename libtraceevent 'private' struct member to 'priv' so that it works in C++, from Steven Rostedt - Remove lots of exit()/die() calls from tools so that the main perf exit routine can take place, from David Ahern - Fix x86 build on x86-64, from David Ahern. - {int,str,rb}list fixes from Suzuki K Poulose - perf.data header fixes from Namhyung Kim - Allow user to indicate objdump path, needed in cross environments, from Maciek Borzecki - Fix hardware cache event name generation, fix from Jiri Olsa - Add round trip test for sw, hw and cache event names, catching the problem Jiri fixed, after Jiri's patch, the test passes successfully. - Clean target should do clean for lib/traceevent too, fix from David Ahern - Check the right variable for allocation failure, fix from Namhyung Kim - Set up evsel->tp_format regardless of evsel->name being set already, fix from Namhyung Kim - Oprofile fixes from Robert Richter. - Remove perf_event_attr needless version inflation, from Jiri Olsa - Introduce libtraceevent strerror like error reporting facility, from Namhyung Kim - Add pmu mappings to perf.data header and use event names from cmd line, from Robert Richter - Fix include order for bison/flex-generated C files, from Ben Hutchings - Build fixes and documentation corrections from David Ahern - Assorted cleanups from Robert Richter - Let O= makes handle relative paths, from Steven Rostedt - perf script python fixes, from Feng Tang. - Initial bash completion support, from Frederic Weisbecker - Allow building without libelf, from Namhyung Kim. - Support DWARF CFI based unwind to have callchains when %bp based unwinding is not possible, from Jiri Olsa. - Symbol resolution fixes, while fixing support PPC64 files with an .opt ELF section was the end goal, several fixes for code that handles all architectures and cleanups are included, from Cody Schafer. - Assorted fixes for Documentation and build in 32 bit, from Robert Richter - Cache the libtraceevent event_format associated to each evsel early, so that we avoid relookups, i.e. calling pevent_find_event repeatedly when processing tracepoint events. [ This is to reduce the surface contact with libtraceevents and make clear what is that the perf tools needs from that lib: so far parsing the common and per event fields. ] - Don't stop the build if the audit libraries are not installed, fix from Namhyung Kim. - Fix bfd.h/libbfd detection with recent binutils, from Markus Trippelsdorf. - Improve warning message when libunwind devel packages not present, from Jiri Olsa" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (282 commits) perf trace: Add aliases for some syscalls perf probe: Print an enum type variable in "enum variable-name" format when showing accessible variables perf tools: Check libaudit availability for perf-trace builtin perf hists: Add missing period_* fields when collapsing a hist entry perf trace: New tool perf evsel: Export the event_format constructor perf evsel: Introduce rawptr() method perf tools: Use perf_evsel__newtp in the event parser perf evsel: The tracepoint constructor should store sys:name perf evlist: Introduce set_filter() method perf evlist: Renane set_filters method to apply_filters perf test: Add test to check we correctly parse and match syscall open parms perf evsel: Handle endianity in intval method perf evsel: Know if byte swap is needed perf tools: Allow handling a NULL cpu_map as meaning "all cpus" perf evsel: Improve tracepoint constructor setup tools lib traceevent: Fix error path on pevent_parse_event perf test: Fix build failure trace: Move trace event enable from fs_initcall to core_initcall tracing: Add an option for disabling markers ...
2012-10-01Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull trivial irq core update from Ingo Molnar: "Two symbol exports for modular irq-chip drivers" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Export dummy_irq_chip genirq: Export irq_set_chip_and_handler_name()
2012-10-01Merge branch 'core-locking-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core locking changes from Ingo Molnar: "It includes a lockdep improvement plus a spinlock inlining Kconfig cleanup." * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking: Adjust spin lock inlining Kconfig options lockdep: Check if nested lock is actually held
2012-10-01Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core kernel fixes from Ingo Molnar: "This is a complex task_work series from Oleg that fixes the bug that this VFS commit tried to fix: d35abdb28824 hold task_lock around checks in keyctl but solves the problem without the lockup regression that d35abdb28824 introduced in v3.6. This series came late in v3.6 and I did not feel confident about it so late in the cycle. Might be worth backporting to -stable if it proves itself upstream." * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: task_work: Simplify the usage in ptrace_notify() and get_signal_to_deliver() task_work: Revert "hold task_lock around checks in keyctl" task_work: task_work_add() should not succeed after exit_task_work() task_work: Make task_work_add() lockless
2012-09-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/team/team.c drivers/net/usb/qmi_wwan.c net/batman-adv/bat_iv_ogm.c net/ipv4/fib_frontend.c net/ipv4/route.c net/l2tp/l2tp_netlink.c The team, fib_frontend, route, and l2tp_netlink conflicts were simply overlapping changes. qmi_wwan and bat_iv_ogm were of the "use HEAD" variety. With help from Antonio Quartulli. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-26kdb: Implement disable_nmi commandAnton Vorontsov
This command disables NMI-entry. If NMI source has been previously shared with a serial console ("debug port"), this effectively releases the port from KDB exclusive use, and makes the console available for normal use. Of course, NMI can be reenabled, enable_nmi modparam is used for that: echo 1 > /sys/module/kdb/parameters/enable_nmi Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26kernel/debug: Mask KGDB NMI upon entryAnton Vorontsov
The new arch callback should manage NMIs that usually cause KGDB to enter. That is, not all NMIs should be enabled/disabled, but only those that issue kgdb_handle_exception(). We must mask it as serial-line interrupt can be used as an NMI, so if the original KGDB-entry cause was say a breakpoint, then every input to KDB console will cause KGDB to reenter, which we don't want. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26rcu: Apply micro-optimization and int/bool fixes to RCU's idle handlingPaul E. McKenney
Checking "user" before "is_idle_task()" allows better optimizations in cases where inlining is possible. Also, "bool" should be passed "true" or "false" rather than "1" or "0". This commit therefore makes these changes, as noted in Josh's review. Reported-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: Userspace RCU extended QS selftestFrederic Weisbecker
Provide a config option that enables the userspace RCU extended quiescent state on every CPUs by default. This is for testing purpose. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: Exit RCU extended QS on user preemptionFrederic Weisbecker
When exceptions or irq are about to resume userspace, if the task needs to be rescheduled, the arch low level code calls schedule() directly. If we call it, it is because we have the TIF_RESCHED flag: - It can be set after random local calls to set_need_resched() (RCU, drm, ...) - A wake up happened and the CPU needs preemption. This can happen in several ways: * Remotely: the remote waking CPU has set TIF_RESCHED and send the wakee an IPI to schedule the new task. * Remotely enqueued: the remote waking CPU sends an IPI to the target and the wake up is made by the target. * Locally: waking CPU == wakee CPU and the wakeup is done locally. set_need_resched() is called without IPI. In the case of local and remotely enqueued wake ups, the tick can be restarted when we enqueue the new task and RCU can exit the extended quiescent state at the same time. Then by the time we reach irq exit path and we call schedule, we are not in RCU user mode. But if we call schedule() only because something called set_need_resched(), RCU may still be in user mode when we reach schedule. Also if a wake up is done remotely, the CPU might see the TIF_RESCHED flag and call schedule while the IPI has not yet happen to restart the tick and exit RCU user mode. We need to manually protect against these corner cases. Create a new API schedule_user() that calls schedule() inside rcu_user_exit()-rcu_user_enter() in order to protect it. Archs will need to rely on it now to implement user preemption safely. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: Exit RCU extended QS on kernel preemption after irq/exceptionFrederic Weisbecker
When an exception or an irq exits, and we are going to resume into interrupted kernel code, the low level architecture code calls preempt_schedule_irq() if there is a need to reschedule. If the interrupt/exception occured between a call to rcu_user_enter() (from syscall exit, exception exit, do_notify_resume exit, ...) and a real resume to userspace (iret,...), preempt_schedule_irq() can be called whereas RCU thinks we are in userspace. But preempt_schedule_irq() is going to run kernel code and may be some RCU read side critical section. We must exit the userspace extended quiescent state before we call it. To solve this, just call rcu_user_exit() in the beginning of preempt_schedule_irq(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: Switch task's syscall hooks on context switchFrederic Weisbecker
Clear the syscalls hook of a task when it's scheduled out so that if the task migrates, it doesn't run the syscall slow path on a CPU that might not need it. Also set the syscalls hook on the next task if needed. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: Ignore userspace extended quiescent state by defaultFrederic Weisbecker
By default we don't want to enter into RCU extended quiescent state while in userspace because doing this produces some overhead (eg: use of syscall slowpath). Set it off by default and ready to run when some feature like adaptive tickless need it. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: Allow rcu_user_enter()/exit() to nestFrederic Weisbecker
Allow calls to rcu_user_enter() even if we are already in userspace (as seen by RCU) and allow calls to rcu_user_exit() even if we are already in the kernel. This makes the APIs more flexible to be called from architectures. Exception entries for example won't need to know if they come from userspace before calling rcu_user_exit(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: Settle config for userspace extended quiescent stateFrederic Weisbecker
Create a new config option under the RCU menu that put CPUs under RCU extended quiescent state (as in dynticks idle mode) when they run in userspace. This require some contribution from architectures to hook into kernel and userspace boundaries. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: Make RCU_FAST_NO_HZ handle adaptive ticksPaul E. McKenney
The current implementation of RCU_FAST_NO_HZ tries reasonably hard to rid the current CPU of RCU callbacks. This is appropriate when the CPU is entering idle, where it doesn't have much useful to do anyway, but is most definitely not what you want when transitioning to user-mode execution. This commit therefore detects the adaptive-tick case, and refrains from burning CPU time getting rid of RCU callbacks in that case. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: New rcu_user_enter_after_irq() and rcu_user_exit_after_irq() APIsFrederic Weisbecker
In some cases, it is necessary to enter or exit userspace-RCU-idle mode from an interrupt handler, for example, if some other CPU sends this CPU a resched IPI. In this case, the current CPU would enter the IPI handler in userspace-RCU-idle mode, but would need to exit the IPI handler after having exited that mode. To allow this to work, this commit adds two new APIs to TREE_RCU: - rcu_user_enter_after_irq(). This must be called from an interrupt between rcu_irq_enter() and rcu_irq_exit(). After the irq calls rcu_irq_exit(), the irq handler will return into an RCU extended quiescent state. In theory, this interrupt is never a nested interrupt, but in practice it might interrupt softirq, which looks to RCU like a nested interrupt. - rcu_user_exit_after_irq(). This must be called from a non-nesting interrupt, interrupting an RCU extended quiescent state, also between rcu_irq_enter() and rcu_irq_exit(). After the irq calls rcu_irq_exit(), the irq handler will return in an RCU non-quiescent state. [ Combined with "Allow calls to rcu_exit_user_irq from nesting irqs." ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-26rcu: New rcu_user_enter() and rcu_user_exit() APIsFrederic Weisbecker
RCU currently insists that only idle tasks can enter RCU idle mode, which prohibits an adaptive tickless kernel (AKA nohz cpusets), which in turn would mean that usermode execution would always take scheduling-clock interrupts, even when there is only one task runnable on the CPU in question. This commit therefore adds rcu_user_enter() and rcu_user_exit(), which allow non-idle tasks to enter RCU idle mode. These are quite similar to rcu_idle_enter() and rcu_idle_exit(), respectively, except that they omit the idle-task checks. [ Updated to use "user" flag rather than separate check functions. ] [ paulmck: Updated to drop exports of new functions based on Josh's patch getting rid of the need for them. ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-25Merge remote-tracking branch 'tip/core/rcu' into next.2012.09.25bPaul E. McKenney
Resolved conflict in kernel/sched/core.c using Peter Zijlstra's approach from https://lkml.org/lkml/2012/9/5/585.
2012-09-25Merge remote-tracking branch 'tip/smp/hotplug' into next.2012.09.25bPaul E. McKenney
The conflicts between kernel/rcutree.h and kernel/rcutree_plugin.h were due to adjacent insertions and deletions, which were resolved by simply accepting the changes on both branches.
2012-09-25vtime: Consolidate system/idle context detectionFrederic Weisbecker
Move the code that finds out to which context we account the cputime into generic layer. Archs that consider the whole time spent in the idle task as idle time (ia64, powerpc) can rely on the generic vtime_account() and implement vtime_account_system() and vtime_account_idle(), letting the generic code to decide when to call which API. Archs that have their own meaning of idle time, such as s390 that only considers the time spent in CPU low power mode as idle time, can just override vtime_account(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
2012-09-25cputime: Use a proper subsystem naming for vtime related APIsFrederic Weisbecker
Use a naming based on vtime as a prefix for virtual based cputime accounting APIs: - account_system_vtime() -> vtime_account() - account_switch_vtime() -> vtime_task_switch() It makes it easier to allow for further declension such as vtime_account_system(), vtime_account_idle(), ... if we want to find out the context we account to from generic code. This also make it better to know on which subsystem these APIs refer to. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
2012-09-24Merge branches 'bigrt.2012.09.23a', 'doctorture.2012.09.23a', ↵Paul E. McKenney
'fixes.2012.09.23a', 'hotplug.2012.09.23a' and 'idlechop.2012.09.23a' into HEAD bigrt.2012.09.23a contains additional commits to reduce scheduling latency from RCU on huge systems (many hundrends or thousands of CPUs). doctorture.2012.09.23a contains documentation changes and rcutorture fixes. fixes.2012.09.23a contains miscellaneous fixes. hotplug.2012.09.23a contains CPU-hotplug-related changes. idle.2012.09.23a fixes architectures for which RCU no longer considered the idle loop to be a quiescent state due to earlier adaptive-dynticks changes. Affected architectures are alpha, cris, frv, h8300, m32r, m68k, mn10300, parisc, score, xtensa, and ia64.
2012-09-24net: use a per task frag allocatorEric Dumazet
We currently use a per socket order-0 page cache for tcp_sendmsg() operations. This page is used to build fragments for skbs. Its done to increase probability of coalescing small write() into single segments in skbs still in write queue (not yet sent) But it wastes a lot of memory for applications handling many mostly idle sockets, since each socket holds one page in sk->sk_sndmsg_page Its also quite inefficient to build TSO 64KB packets, because we need about 16 pages per skb on arches where PAGE_SIZE = 4096, so we hit page allocator more than wanted. This patch adds a per task frag allocator and uses bigger pages, if available. An automatic fallback is done in case of memory pressure. (up to 32768 bytes per frag, thats order-3 pages on x86) This increases TCP stream performance by 20% on loopback device, but also benefits on other network devices, since 8x less frags are mapped on transmit and unmapped on tx completion. Alexander Duyck mentioned a probable performance win on systems with IOMMU enabled. Its possible some SG enabled hardware cant cope with bigger fragments, but their ndo_start_xmit() should already handle this, splitting a fragment in sub fragments, since some arches have PAGE_SIZE=65536 Successfully tested on various ethernet devices. (ixgbe, igb, bnx2x, tg3, mellanox mlx4) Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Cc: Vijay Subramanian <subramanian.vijay@gmail.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-24trace: Move trace event enable from fs_initcall to core_initcallEzequiel Garcia
This patch splits trace event initialization in two stages: * ftrace enable * sysfs event entry creation This allows to capture trace events from an earlier point by using 'trace_event' kernel parameter and is important to trace boot-up allocations. Note that, in order to enable events at core_initcall, it's necessary to move init_ftrace_syscalls() from core_initcall to early_initcall. Link: http://lkml.kernel.org/r/1347461277-25302-1-git-send-email-elezegarcia@gmail.com Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-09-24tracing: Add an option for disabling markersMandeep Singh Baines
In our application, we have trace markers spread through user-space. We have markers in GL, X, etc. These are super handy for Chrome's about:tracing feature (Chrome + system + kernel trace view), but can be very distracting when you're trying to debug a kernel issue. I normally, use "grep -v tracing_mark_write" but it would be nice if I could just temporarily disable markers all together. Link: http://lkml.kernel.org/r/1347066739-26285-1-git-send-email-msb@chromium.org CC: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-09-23sched: Fix load avg vs cpu-hotplugPeter Zijlstra
Rabik and Paul reported two different issues related to the same few lines of code. Rabik's issue is that the nr_uninterruptible migration code is wrong in that he sees artifacts due to this (Rabik please do expand in more detail). Paul's issue is that this code as it stands relies on us using stop_machine() for unplug, we all would like to remove this assumption so that eventually we can remove this stop_machine() usage altogether. The only reason we'd have to migrate nr_uninterruptible is so that we could use for_each_online_cpu() loops in favour of for_each_possible_cpu() loops, however since nr_uninterruptible() is the only such loop and its using possible lets not bother at all. The problem Rabik sees is (probably) caused by the fact that by migrating nr_uninterruptible we screw rq->calc_load_active for both rqs involved. So don't bother with fancy migration schemes (meaning we now have to keep using for_each_possible_cpu()) and instead fold any nr_active delta after we migrate all tasks away to make sure we don't have any skewed nr_active accounting. [ paulmck: Move call to calc_load_migration to CPU_DEAD to avoid miscounting noted by Rakib. ] Reported-by: Rakib Mullick <rakib.mullick@gmail.com> Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
2012-09-23rcu: Disallow callback registry on offline CPUsPaul E. McKenney
Posting a callback after the CPU_DEAD notifier effectively leaks that callback unless/until that CPU comes back online. Silence is unhelpful when attempting to track down such leaks, so this commit emits a WARN_ON_ONCE() and unconditionally leaks the callback when an offline CPU attempts to register a callback. The rdp->nxttail[RCU_NEXT_TAIL] is set to NULL in the CPU_DEAD notifier and restored in the CPU_UP_PREPARE notifier, allowing _call_rcu() to determine exactly when posting callbacks is illegal. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23rcu: Remove _rcu_barrier() dependency on __stop_machine()Paul E. McKenney
Currently, _rcu_barrier() relies on preempt_disable() to prevent any CPU from going offline, which in turn depends on CPU hotplug's use of __stop_machine(). This patch therefore makes _rcu_barrier() use get_online_cpus() to block CPU-hotplug operations. This has the added benefit of removing the need for _rcu_barrier() to adopt callbacks: Because CPU-hotplug operations are excluded, there can be no callbacks to adopt. This commit simplifies the code accordingly. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23rcu: Fix CONFIG_RCU_FAST_NO_HZ stall warning messagePaul E. McKenney
The print_cpu_stall_fast_no_hz() function attempts to print -1 when the ->idle_gp_timer is not pending, but unsigned arithmetic causes it to instead print ULONG_MAX, which is 4294967295 on 32-bit systems and 18446744073709551615 on 64-bit systems. Neither of these are the most reader-friendly values, so this commit instead causes "timer not pending" to be printed when ->idle_gp_timer is not pending. Reported-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-09-23rcu: Move TINY_RCU quiescent state out of extended quiescent stateLi Zhong
TINY_RCU's rcu_idle_enter_common() invokes rcu_sched_qs() in order to inform the RCU core of the quiescent state implied by idle entry. Of course, idle is also an extended quiescent state, so that the call to rcu_sched_qs() speeds up RCU's invoking of any callbacks that might be queued. This speed-up is important when entering into dyntick-idle mode -- if there are no further scheduling-clock interrupts, the callbacks might never be invoked, which could result in a system hang. However, processing callbacks does event tracing, which in turn implies RCU read-side critical sections, which are illegal in extended quiescent states. This patch therefore moves the call to rcu_sched_qs() so that it precedes the point at which we inform lockdep that RCU has entered an extended quiescent state. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-09-23time: RCU permitted to stop idle entry via softirqPaul E. McKenney
The can_stop_idle_tick() function complains if a softirq vector is raised too late in the idle-entry process, presumably in order to prevent dangling softirq invocations from being delayed across the full idle period, which might be indefinitely long -- and if softirq was asserted any later than the call to this function, such a delay might well happen. However, RCU needs to be able to use softirq to stop idle entry in order to be able to drain RCU callbacks from the current CPU, which in turn enables faster entry into dyntick-idle mode, which in turn reduces power consumption. Because RCU takes this action at a well-defined point in the idle-entry path, it is safe for RCU to take this approach. This commit therefore silences the error message that is sometimes produced when the going-idle CPU suddenly finds that it has an RCU_SOFTIRQ to process. The error message will continue to be issued for other softirq vectors. Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23rcu: Move TINY_PREEMPT_RCU away from raw_local_irq_save()Paul E. McKenney
The use of raw_local_irq_save() is unnecessary, given that local_irq_save() really does disable interrupts. Also, it appears to interfere with lockdep. Therefore, this commit moves to local_irq_save(). Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Fengguang Wu <fengguang.wu@intel.com>
2012-09-23rcu: Remove redundant memory barrier from __call_rcu()Paul E. McKenney
The first memory barrier in __call_rcu() is supposed to order any updates done beforehand by the caller against the actual queuing of the callback. However, the second memory barrier (which is intended to order incrementing the queue lengths before queuing the callback) is also between the caller's updates and the queuing of the callback. The second memory barrier can therefore serve both purposes. This commit therefore removes the first memory barrier. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23rcu: Avoid spurious RCU CPU stall warningsPaul E. McKenney
If a given CPU avoids the idle loop but also avoids starting a new RCU grace period for a full minute, RCU can issue spurious RCU CPU stall warnings. This commit fixes this issue by adding a check for ongoing grace period to avoid these spurious stall warnings. Reported-by: Becky Bruce <bgillbruce@gmail.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23rcu: Protect rcu_node accesses during CPU stall warningsPaul E. McKenney
The print_other_cpu_stall() function accesses a number of rcu_node fields without protection from the ->lock. In theory, this is not a problem because the fields accessed are all integers, but in practice the compiler can get nasty. Therefore, the commit extends the existing critical section to cover the entire loop body. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-09-23rcu: Avoid rcu_print_detail_task_stall_rnp() segfaultPaul E. McKenney
The rcu_print_detail_task_stall_rnp() function invokes rcu_preempt_blocked_readers_cgp() to verify that there are some preempted RCU readers blocking the current grace period outside of the protection of the rcu_node structure's ->lock. This means that the last blocked reader might exit its RCU read-side critical section and remove itself from the ->blkd_tasks list before the ->lock is acquired, resulting in a segmentation fault when the subsequent code attempts to dereference the now-NULL gp_tasks pointer. This commit therefore moves the test under the lock. This will not have measurable effect on lock contention because this code is invoked only when printing RCU CPU stall warnings, in other words, in the common case, never. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-09-23rcu: Apply for_each_rcu_flavor() to increment_cpu_stall_ticks()Paul E. McKenney
The increment_cpu_stall_ticks() function listed each RCU flavor explicitly, with an ifdef to handle preemptible RCU. This commit therefore applies for_each_rcu_flavor() to save a line of code. Because this commit switches from a code-based enumeration of the flavors of RCU to an rcu_state-list-based enumeration, it is no longer possible to apply __get_cpu_var() to the per-CPU rcu_data structures. We instead use __this_cpu_var() on the rcu_state structure's ->rda field that references the corresponding rcu_data structures. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-09-23rcu: Fix obsolete rcu_initiate_boost() header commentPaul E. McKenney
Commit 1217ed1b (rcu: permit rcu_read_unlock() to be called while holding runqueue locks) made rcu_initiate_boost() restore irq state when releasing the rcu_node structure's ->lock, but failed to update the header comment accordingly. This commit therefore brings the header comment up to date. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23rcu: Make offline-CPU checking allow for indefinite delaysPaul E. McKenney
The rcu_implicit_offline_qs() function implicitly assumed that execution would progress predictably when interrupts are disabled, which is of course not guaranteed when running on a hypervisor. Furthermore, this function is short, and is called from one place only in a short function. This commit therefore ensures that the timing is checked before checking the condition, which guarantees correct behavior even given indefinite delays. It also inlines rcu_implicit_offline_qs() into rcu_implicit_dynticks_qs(). Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>