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2012-08-28uprobes: Fold uprobe_reset_state() into uprobe_dup_mmap()Oleg Nesterov
Now that we have uprobe_dup_mmap() we can fold uprobe_reset_state() into the new hook and remove it. mmput()->uprobe_clear_state() can't be called before dup_mmap(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2012-08-28uprobes: Introduce MMF_HAS_UPROBESOleg Nesterov
Add the new MMF_HAS_UPROBES flag. It is set by install_breakpoint() and it is copied by dup_mmap(), uprobe_pre_sstep_notifier() checks it to avoid the slow path if the task was never probed. Perhaps it makes sense to check it in valid_vma(is_register => false) as well. This needs the new dup_mmap()->uprobe_dup_mmap() hook. We can't use uprobe_reset_state() or put MMF_HAS_UPROBES into MMF_INIT_MASK, we need oldmm->mmap_sem to avoid the race with uprobe_register() or mmap() from another thread. Currently we never clear this bit, it can be false-positive after uprobe_unregister() or uprobe_munmap() or if dup_mmap() hits the probed VM_DONTCOPY vma. But this is fine correctness-wise and has no effect unless the task hits the non-uprobe breakpoint. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2012-08-28uprobes: Do not use -EEXIST in install_breakpoint() pathsOleg Nesterov
-EEXIST from install_breakpoint() no longer makes sense, all callers should simply treat it as "success". Change the code to return zero and simplify register_for_each_vma(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2012-08-28uprobes: Change uprobe_mmap() to ignore the errors but check ↵Oleg Nesterov
fatal_signal_pending() Once install_breakpoint() fails uprobe_mmap() "ignores" all other uprobes and returns the error. It was never really needed to to stop after the first error, and in fact it was always wrong at least in -ENOTSUPP case. Change uprobe_mmap() to ignore the errors and always return 0. This is not what we want in the long term, but until we teach the callers to handle the failure it would be better to remove the pointless complications. And this doesn't look too bad, the only "reasonable" error is ENOMEM but in this case the caller should be oom-killed in the likely case or the system has more serious problems. However it makes sense to stop if fatal_signal_pending() == T. In particular this helps if the task was oom-killed. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2012-08-28uprobes: Kill dup_mmap()->uprobe_mmap(), simplify uprobe_mmap/munmapOleg Nesterov
1. Kill dup_mmap()->uprobe_mmap(), it was only needed to calculate new_mm->uprobes_state.count removed by the previous patch. If the forking process has a pending uprobe (int3) in vma, it will be copied by copy_page_range(), note that it checks vma->anon_vma so "Don't copy ptes" is not possible after install_breakpoint() which does anon_vma_prepare(). 2. Remove is_swbp_at_addr() and "int count" in uprobe_mmap(). Again, this was needed for uprobes_state.count. As a side effect this fixes the bug pointed out by Srikar, this code lacked the necessary put_uprobe(). 3. uprobe_munmap() becomes a nop after the previous patch. Remove the meaningless code but do not remove the helper, we will need it. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2012-08-28uprobes: Kill uprobes_state->countOleg Nesterov
uprobes_state->count is only needed to avoid the slow path in uprobe_pre_sstep_notifier(). It is also checked in uprobe_munmap() but ironically its only goal to decrement this counter. However, it is very broken. Just some examples: - uprobe_mmap() can race with uprobe_unregister() and wrongly increment the counter if it hits the non-uprobe "int3". Note that install_breakpoint() checks ->consumers first and returns -EEXIST if it is NULL. "atomic_sub() if error" in uprobe_mmap() looks obviously wrong too. - uprobe_munmap() can race with uprobe_register() and wrongly decrement the counter by the same reason. - Suppose an appication tries to increase the mmapped area via sys_mremap(). vma_adjust() does uprobe_munmap(whole_vma) first, this can nullify the counter temporarily and race with another thread which can hit the bp, the application will be killed by SIGTRAP. - Suppose an application mmaps 2 consecutive areas in the same file and one (or both) of these areas has uprobes. In the likely case mmap_region()->vma_merge() suceeds. Like above, this leads to uprobe_munmap/uprobe_mmap from vma_merge()->vma_adjust() but then mmap_region() does another uprobe_mmap(resulting_vma) and doubles the counter. This patch only removes this counter and fixes the compile errors, then we will try to cleanup the changed code and add something else instead. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2012-08-28uprobes: Remove check for uprobe variable in handle_swbp()Sebastian Andrzej Siewior
by the time we get here (after we pass cleanup_ret) uprobe is always is set. If it is NULL we leave very early in the code. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2012-08-28uprobes: Remove redundant lock_page/unlock_pageSrikar Dronamraju
Since read_opcode() reads from the referenced page and doesnt modify the page contents nor the page attributes, there is no need to lock the page. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2012-08-28Merge branch 'perf/urgent' into perf/coreIngo Molnar
Pick up the latest fixes because upcoming uprobes changes will rely on it. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-26Merge remote-tracking branch 'upstream/master' into queueMarcelo Tosatti
Merging critical fixes from upstream required for development. * upstream/master: (809 commits) libata: Add a space to " 2GB ATA Flash Disk" DMA blacklist entry Revert "powerpc: Update g5_defconfig" powerpc/perf: Use pmc_overflow() to detect rolled back events powerpc: Fix VMX in interrupt check in POWER7 copy loops powerpc: POWER7 copy_to_user/copy_from_user patch applied twice powerpc: Fix personality handling in ppc64_personality() powerpc/dma-iommu: Fix IOMMU window check powerpc: Remove unnecessary ifdefs powerpc/kgdb: Restore current_thread_info properly powerpc/kgdb: Bail out of KGDB when we've been triggered powerpc/kgdb: Do not set kgdb_single_step on ppc powerpc/mpic_msgr: Add missing includes powerpc: Fix null pointer deref in perf hardware breakpoints powerpc: Fixup whitespace in xmon powerpc: Fix xmon dl command for new printk implementation xfs: check for possible overflow in xfs_ioc_trim xfs: unlock the AGI buffer when looping in xfs_dialloc xfs: fix uninitialised variable in xfs_rtbuf_get() powerpc/fsl: fix "Failed to mount /dev: No such device" errors powerpc/fsl: update defconfigs ... Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-24cgroup: rename subsys_bits to subsys_maskAristeu Rozanski
In a previous discussion, Tejun Heo suggested to rename references to subsys_bits (added_bits, removed_bits, etc) by something more meaningful. Cc: Li Zefan <lizefan@huawei.com> Cc: Tejun Heo <tj@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Lennart Poettering <lpoetter@redhat.com> Signed-off-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-08-24cgroup: add xattr supportAristeu Rozanski
This is one of the items in the plumber's wish list. For use cases: >> What would the use case be for this? > > Attaching meta information to services, in an easily discoverable > way. For example, in systemd we create one cgroup for each service, and > could then store data like the main pid of the specific service as an > xattr on the cgroup itself. That way we'd have almost all service state > in the cgroupfs, which would make it possible to terminate systemd and > later restart it without losing any state information. But there's more: > for example, some very peculiar services cannot be terminated on > shutdown (i.e. fakeraid DM stuff) and it would be really nice if the > services in question could just mark that on their cgroup, by setting an > xattr. On the more desktopy side of things there are other > possibilities: for example there are plans defining what an application > is along the lines of a cgroup (i.e. an app being a collection of > processes). With xattrs one could then attach an icon or human readable > program name on the cgroup. > > The key idea is that this would allow attaching runtime meta information > to cgroups and everything they model (services, apps, vms), that doesn't > need any complex userspace infrastructure, has good access control > (i.e. because the file system enforces that anyway, and there's the > "trusted." xattr namespace), notifications (inotify), and can easily be > shared among applications. > > Lennart v7: - no changes v6: - remove user xattr namespace, only allow trusted and security v5: - check for capabilities before setting/removing xattrs v4: - no changes v3: - instead of config option, use mount option to enable xattr support Original-patch-by: Li Zefan <lizefan@huawei.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Tejun Heo <tj@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Lennart Poettering <lpoetter@redhat.com> Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-08-24cgroup: revise how we re-populate root directoryAristeu Rozanski
When remounting cgroupfs with some subsystems added to it and some removed, cgroup will remove all the files in root directory and then re-popluate it. What I'm doing here is, only remove files which belong to subsystems that are to be unbinded, and only create files for newly-added subsystems. The purpose is to have all other files untouched. This is a preparation for cgroup xattr support. v7: - checkpatch warnings fixed v6: - no changes v5: - no changes v4: - refactored cgroup_clear_directory() to not use cgroup_rm_file() - instead of going thru the list of files, get the file list using the subsystems - use 'subsys_mask' instead of {added,removed}_bits and made cgroup_populate_dir() to match the parameters with cgroup_clear_directory() v3: - refresh patches after recent refactoring Original-patch-by: Li Zefan <lizefan@huawei.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Lennart Poettering <lpoetter@redhat.com> Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-08-24Merge branch 'for-next' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace This is an initial merge in of Eric Biederman's work to start adding user namespace support to the networking. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-23userns: Make credential debugging user namespace safe.Eric W. Biederman
Cc: David Howells <dhowells@redhat.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-08-23Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "This tree contains misc fixlets: a perf script python binding fix, a uprobes fix and a syscall tracing fix." * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf tools: Add missing files to build the python binding uprobes: Fix mmap_region()'s mm->mm_rb corruption if uprobe_mmap() fails tracing/syscalls: Fix perf syscall tracing when syscall_nr == -1
2012-08-23Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Mostly small fixes for the fallout of the timekeeping overhaul in 3.6 along with stable fixes to address an accumulation problem and missing sanity checks for RTC readouts and user space provided values." * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: time: Avoid making adjustments if we haven't accumulated anything time: Avoid potential shift overflow with large shift values time: Fix casting issue in timekeeping_forward_now time: Ensure we normalize the timekeeper in tk_xtime_add time: Improve sanity checking of timekeeping inputs
2012-08-23ftrace: Do not test frame pointers if -mfentry is usedSteven Rostedt
The function graph has a test to check if the frame pointer is corrupted, which can happen with various options of gcc with mcount. But this is not an issue with -mfentry as -mfentry does not need nor use frame pointers for function graph tracing. Link: http://lkml.kernel.org/r/20120807194059.773895870@goodmis.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-23ftrace: Add -mfentry to Makefile on function tracerSteven Rostedt
Thanks to Andi Kleen, gcc 4.6.0 now supports -mfentry for x86 (and hopefully soon for other archs). What this does is to have the function profiler start at the beginning of the function instead of after the stack is set up. As plain -pg (mcount) is called after the stack is set up, and in some cases can have issues with the function graph tracer. It also requires frame pointers to be enabled. The -mfentry now calls __fentry__ at the beginning of the function. This allows for compiling without frame pointers and even has the ability to access parameters if needed. If the architecture and the compiler both support -mfentry then use that instead. Link: http://lkml.kernel.org/r/20120807194059.392617243@goodmis.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-23x86/smp: Don't ever patch back to UP if we unplug cpusRusty Russell
We still patch SMP instructions to UP variants if we boot with a single CPU, but not at any other time. In particular, not if we unplug CPUs to return to a single cpu. Paul McKenney points out: mean offline overhead is 6251/48=130.2 milliseconds. If I remove the alternatives_smp_switch() from the offline path [...] the mean offline overhead is 550/42=13.1 milliseconds Basically, we're never going to get those 120ms back, and the code is pretty messy. We get rid of: 1) The "smp-alt-once" boot option. It's actually "smp-alt-boot", the documentation is wrong. It's now the default. 2) The skip_smp_alternatives flag used by suspend. 3) arch_disable_nonboot_cpus_begin() and arch_disable_nonboot_cpus_end() which were only used to set this one flag. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul McKenney <paul.mckenney@us.ibm.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/87vcgwwive.fsf@rustcorp.com.au Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-23PM / Freezer: Fix small typo "regrigerator"Sedat Dilek
Noticed when digging into a suspend issue in linux-next (next-20120821). For more details see <http://marc.info/?t=134554708000002&r=1&w=2>. Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-08-22time: Avoid making adjustments if we haven't accumulated anythingJohn Stultz
If update_wall_time() is called and the current offset isn't large enough to accumulate, avoid re-calling timekeeping_adjust which may change the clock freq and can cause 1ns inconsistencies with CLOCK_REALTIME_COARSE/CLOCK_MONOTONIC_COARSE. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1345595449-34965-5-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-22time: Avoid potential shift overflow with large shift valuesJohn Stultz
Andreas Schwab noticed that the 1 << tk->shift could overflow if the shift value was greater than 30, since 1 would be a 32bit long on 32bit architectures. This issue was introduced by 1e75fa8be (time: Condense timekeeper.xtime into xtime_sec) Use 1ULL instead to ensure we don't overflow on the shift. Reported-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1345595449-34965-4-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-22time: Fix casting issue in timekeeping_forward_nowAndreas Schwab
arch_gettimeoffset returns a u32 value which when shifted by tk->shift can overflow. This issue was introduced with 1e75fa8be (time: Condense timekeeper.xtime into xtime_sec) Cast it to u64 first. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1345595449-34965-3-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-22time: Ensure we normalize the timekeeper in tk_xtime_addJohn Stultz
Andreas noticed problems with resume on specific hardware after commit 1e75fa8b (time: Condense timekeeper.xtime into xtime_sec) combined with commit b44d50dca (time: Fix casting issue in tk_set_xtime and tk_xtime_add) After some digging I realized we aren't normalizing the timekeeper after the add. Add the missing normalize call. Reported-by: Andreas Schwab <schwab@linux-m68k.org> Tested-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1345595449-34965-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21workqueue: reimplement cancel_delayed_work() using try_to_grab_pending()Tejun Heo
cancel_delayed_work() can't be called from IRQ handlers due to its use of del_timer_sync() and can't cancel work items which are already transferred from timer to worklist. Also, unlike other flush and cancel functions, a canceled delayed_work would still point to the last associated cpu_workqueue. If the workqueue is destroyed afterwards and the work item is re-used on a different workqueue, the queueing code can oops trying to dereference already freed cpu_workqueue. This patch reimplements cancel_delayed_work() using try_to_grab_pending() and set_work_cpu_and_clear_pending(). This allows the function to be called from IRQ handlers and makes its behavior consistent with other flush / cancel functions. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org>
2012-08-21workqueue: use irqsafe timer for delayed_workTejun Heo
Up to now, for delayed_works, try_to_grab_pending() couldn't be used from IRQ handlers because IRQs may happen while delayed_work_timer_fn() is in progress leading to indefinite -EAGAIN. This patch makes delayed_work use the new TIMER_IRQSAFE flag for delayed_work->timer. This makes try_to_grab_pending() and thus mod_delayed_work_on() safe to call from IRQ handlers. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-08-21Merge branch 'timers/core' of ↵Tejun Heo
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into for-3.7
2012-08-21Merge branch 'audit-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull audit-tree fixes from Miklos Szeredi: "The audit subsystem maintainers (Al and Eric) are not responding to repeated resends. Eric did ack them a while ago, but no response since then. So I'm sending these directly to you." * 'audit-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: audit: clean up refcounting in audit-tree audit: fix refcounting in audit-tree audit: don't free_chunk() after fsnotify_add_mark()
2012-08-21task_work: add a scheduling point in task_work_run()Eric Dumazet
It seems commit 4a9d4b024a31 ("switch fput to task_work_add") re- introduced the problem addressed in 944be0b22472 ("close_files(): add scheduling point") If a server process with a lot of files (say 2 million tcp sockets) is killed, we can spend a lot of time in task_work_run() and trigger a soft lockup. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21timer: Implement TIMER_IRQSAFETejun Heo
Timer internals are protected with irq-safe locks but timer execution isn't, so a timer being dequeued for execution and its execution aren't atomic against IRQs. This makes it impossible to wait for its completion from IRQ handlers and difficult to shoot down a timer from IRQ handlers. This issue caused some issues for delayed_work interface. Because there's no way to reliably shoot down delayed_work->timer from IRQ handlers, __cancel_delayed_work() can't share the logic to steal the target delayed_work with cancel_delayed_work_sync(), and can only steal delayed_works which are on queued on timer. Similarly, the pending mod_delayed_work() can't be used from IRQ handlers. This patch adds a new timer flag TIMER_IRQSAFE, which makes the timer to be executed without enabling IRQ after dequeueing such that its dequeueing and execution are atomic against IRQ handlers. This makes it safe to wait for the timer's completion from IRQ handlers, for example, using del_timer_sync(). It can never be executing on the local CPU and if executing on other CPUs it won't be interrupted until done. This will enable simplifying delayed_work cancel/mod interface. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/1344449428-24962-5-git-send-email-tj@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21timer: Clean up timer initializersTejun Heo
Over time, timer initializers became messy with unnecessarily duplicated code which are inconsistently spread across timer.h and timer.c. This patch cleans up timer initializers. * timer.c::__init_timer() is renamed to do_init_timer(). * __TIMER_INITIALIZER() added. It takes @flags and all initializers are wrappers around it. * init_timer[_on_stack]_key() now take @flags. * __init_timer[_on_stack]() added. They take @flags and all init macros are wrappers around them. * __setup_timer[_on_stack]() added. It uses __init_timer() and takes @flags. All setup macros are wrappers around the two. Note that this patch doesn't add missing init/setup combinations - e.g. init_timer_deferrable_on_stack(). Adding missing ones is trivial. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/1344449428-24962-4-git-send-email-tj@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21timer: Generalize timer->base flags handlingTejun Heo
To prepare for addition of another flag, generalize timer->base flags handling. * Rename from TBASE_*_FLAG to TIMER_* and make them LU constants. * Define and use TIMER_FLAG_MASK for flags masking so that multiple flags can be handled correctly. * Don't dereference timer->base directly even if !tbase_get_deferrable(). All two such places are already passed in @base, so use it instead. * Make sure tvec_base's alignment is large enough for timer->base flags using BUILD_BUG_ON(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/1344449428-24962-2-git-send-email-tj@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21genirq: Export dummy_irq_chipKuninori Morimoto
Export dummy_irq_chip to modules to allow them to do things such as irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_level_irq); This fixes ERROR: "dummy_irq_chip" [drivers/gpio/gpio-pcf857x.ko] undefined! when gpio-pcf857x.c is being built as a module. Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Greg KH <gregkh@linuxfoundation.org> Link: http://lkml.kernel.org/r/871ujstrp6.wl%25kuninori.morimoto.gx@renesas.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21genirq: Export irq_set_chip_and_handler_name()Kuninori Morimoto
Export irq_set_chip_and_handler_name() to modules to allow them to do things such as irq_set_chip_and_handler(....); This fixes ERROR: "irq_set_chip_and_handler_name" \ [drivers/gpio/gpio-pcf857x.ko] undefined! when gpio-pcf857x.c is being built as a module. Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Greg KH <gregkh@linuxfoundation.org> Link: http://lkml.kernel.org/r/873948trpk.wl%25kuninori.morimoto.gx@renesas.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21Merge branch 'tip/perf/urgent' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/urgent Pull syscall tracing fix from Steve Rostedt. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-21uprobes: Fix mmap_region()'s mm->mm_rb corruption if uprobe_mmap() failsOleg Nesterov
This patch fixes: https://bugzilla.redhat.com/show_bug.cgi?id=843640 If mmap_region()->uprobe_mmap() fails, unmap_and_free_vma path does unmap_region() but does not remove the soon-to-be-freed vma from rb tree. Actually there are more problems but this is how William noticed this bug. Perhaps we could do do_munmap() + return in this case, but in fact it is simply wrong to abort if uprobe_mmap() fails. Until at least we move the !UPROBE_COPY_INSN code from install_breakpoint() to uprobe_register(). For example, uprobe_mmap()->install_breakpoint() can fail if the probed insn is not supported (remember, uprobe_register() succeeds if nobody mmaps inode/offset), mmap() should not fail in this case. dup_mmap()->uprobe_mmap() is wrong too by the same reason, fork() can race with uprobe_register() and fail for no reason if it wins the race and does install_breakpoint() first. And, if nothing else, both mmap_region() and dup_mmap() return success if uprobe_mmap() fails. Change them to ignore the error code from uprobe_mmap(). Reported-and-tested-by: William Cohen <wcohen@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> # v3.5 Cc: Anton Arapov <anton@redhat.com> Cc: William Cohen <wcohen@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120819171042.GB26957@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-21Merge branch 'tip/perf/core-2' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core Pull ftrace fixlets from Steve Rostedt. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-21Merge tag 'perf-core-for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: * Fix include order for bison/flex-generated C files, from Ben Hutchings * Build fixes and documentation corrections from David Ahern * Group parsing support, from Jiri Olsa * UI/gtk refactorings and improvements from Namhyung Kim * NULL deref fix for perf script, from Namhyung Kim * Assorted cleanups from Robert Richter * Let O= makes handle relative paths, from Steven Rostedt * perf script python fixes, from Feng Tang. * Improve 'perf lock' error message when the needed tracepoints are not present, from David Ahern. * 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. * Add a description for the JIT interface, from Andi Kleen. * Assorted fixes for Documentation and build in 32 bit, from Robert Richter * Add support for non-tracepoint events in perf script python, from Feng Tang * 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. ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-21Merge branch 'tip/perf/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core Pull ftrace updates from Steve Rostedt: " This patch series extends 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. " Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-20workqueue: deprecate system_nrt[_freezable]_wqTejun Heo
system_nrt[_freezable]_wq are now spurious. Mark them deprecated and convert all users to system[_freezable]_wq. If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant, so there's no reason to use system_nrt[_freezable]_wq. Please use system[_freezable]_wq instead. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-By: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: David Howells <dhowells@redhat.com>
2012-08-20workqueue: gut system_nrt[_freezable]_wq()Tejun Heo
Now that all workqueues are non-reentrant, system[_freezable]_wq() are equivalent to system_nrt[_freezable]_wq(). Replace the latter with wrappers around system[_freezable]_wq(). The wrapping goes through inline functions so that __deprecated can be added easily. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-08-20workqueue: gut flush[_delayed]_work_sync()Tejun Heo
Now that all workqueues are non-reentrant, flush[_delayed]_work_sync() are equivalent to flush[_delayed]_work(). Drop the separate implementation and make them thin wrappers around flush[_delayed]_work(). * start_flush_work() no longer takes @wait_executing as the only left user - flush_work() - always sets it to %true. * __cancel_work_timer() uses flush_work() instead of wait_on_work(). Signed-off-by: Tejun Heo <tj@kernel.org>
2012-08-20workqueue: make all workqueues non-reentrantTejun Heo
By default, each per-cpu part of a bound workqueue operates separately and a work item may be executing concurrently on different CPUs. The behavior avoids some cross-cpu traffic but leads to subtle weirdities and not-so-subtle contortions in the API. * There's no sane usefulness in allowing a single work item to be executed concurrently on multiple CPUs. People just get the behavior unintentionally and get surprised after learning about it. Most either explicitly synchronize or use non-reentrant/ordered workqueue but this is error-prone. * flush_work() can't wait for multiple instances of the same work item on different CPUs. If a work item is executing on cpu0 and then queued on cpu1, flush_work() can only wait for the one on cpu1. Unfortunately, work items can easily cross CPU boundaries unintentionally when the queueing thread gets migrated. This means that if multiple queuers compete, flush_work() can't even guarantee that the instance queued right before it is finished before returning. * flush_work_sync() was added to work around some of the deficiencies of flush_work(). In addition to the usual flushing, it ensures that all currently executing instances are finished before returning. This operation is expensive as it has to walk all CPUs and at the same time fails to address competing queuer case. Incorrectly using flush_work() when flush_work_sync() is necessary is an easy error to make and can lead to bugs which are difficult to reproduce. * Similar problems exist for flush_delayed_work[_sync](). Other than the cross-cpu access concern, there's no benefit in allowing parallel execution and it's plain silly to have this level of contortion for workqueue which is widely used from core code to extremely obscure drivers. This patch makes all workqueues non-reentrant. If a work item is executing on a different CPU when queueing is requested, it is always queued to that CPU. This guarantees that any given work item can be executing on one CPU at maximum and if a work item is queued and executing, both are on the same CPU. The only behavior change which may affect workqueue users negatively is that non-reentrancy overrides the affinity specified by queue_work_on(). On a reentrant workqueue, the affinity specified by queue_work_on() is always followed. Now, if the work item is executing on one of the CPUs, the work item will be queued there regardless of the requested affinity. I've reviewed all workqueue users which request explicit affinity, and, fortunately, none seems to be crazy enough to exploit parallel execution of the same work item. This adds an additional busy_hash lookup if the work item was previously queued on a different CPU. This shouldn't be noticeable under any sane workload. Work item queueing isn't a very high-frequency operation and they don't jump across CPUs all the time. In a micro benchmark to exaggerate this difference - measuring the time it takes for two work items to repeatedly jump between two CPUs a number (10M) of times with busy_hash table densely populated, the difference was around 3%. While the overhead is measureable, it is only visible in pathological cases and the difference isn't huge. This change brings much needed sanity to workqueue and makes its behavior consistent with timer. I think this is the right tradeoff to make. This enables significant simplification of workqueue API. Simplification patches will follow. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-08-20workqueue: fix checkpatch issuesValentin Ilie
Fixed some checkpatch warnings. tj: adapted to wq/for-3.7 and massaged pr_xxx() format strings a bit. Signed-off-by: Valentin Ilie <valentin.ilie@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org> LKML-Reference: <1345326762-21747-1-git-send-email-valentin.ilie@gmail.com>
2012-08-20Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar. * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix migration thread runtime bogosity sched,rt: fix isolated CPUs leaving root_task_group indefinitely throttled sched,cgroup: Fix up task_groups list sched: fix divide by zero at {thread_group,task}_times sched, cgroup: Reduce rq->lock hold times for large cgroup hierarchies
2012-08-20cputime: Consolidate vtime handling on context switchFrederic Weisbecker
The archs that implement virtual cputime accounting all flush the cputime of a task when it gets descheduled and sometimes set up some ground initialization for the next task to account its cputime. These archs all put their own hooks in their context switch callbacks and handle the off-case themselves. Consolidate this by creating a new account_switch_vtime() callback called in generic code right after a context switch and that these archs must implement to flush the prev task cputime and initialize the next task cputime related state. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.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: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
2012-08-20sched: Move cputime code to its own fileFrederic Weisbecker
Extract cputime code from the giant sched/core.c and put it in its own file. This make it easier to deal with this particular area and de-bloat a bit more core.c Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.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: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
2012-08-19Merge branch 'alpha' (alpha architecture patches)Linus Torvalds
Merge alpha architecture update from Michael Cree: "The Alpha Maintainer, Matt Turner, is currently unavailable, so I have collected up patches that have been posted to the linux-alpha mailing list over the last couple of months, and are forwarding them to you in the hope that you are prepared to accept them via me. The patches by Al Viro and myself I have been running against kernels for two months now so have had quite a bit of testing. All except one patch were intended for the 3.5 kernel but because of Matt's unavailability never got forwarded to you." * emailed patches from Michael Cree <mcree@orcon.net.nz>: (9 commits) alpha: Fix fall-out from disintegrating asm/system.h Redefine ATOMIC_INIT and ATOMIC64_INIT to drop the casts alpha: fix fpu.h usage in userspace alpha/mm/fault.c: Port OOM changes to do_page_fault alpha: take kernel_execve() out of entry.S alpha: take a bunch of syscalls into osf_sys.c alpha: Use new generic strncpy_from_user() and strnlen_user() alpha: Wire up cross memory attach syscalls alpha: Don't export SOCK_NONBLOCK to user space.
2012-08-19alpha: take a bunch of syscalls into osf_sys.cAl Viro
New helper: current_thread_info(). Allows to do a bunch of odd syscalls in C. While we are at it, there had never been a reason to do osf_getpriority() in assembler. We also get "namespace"-aware (read: consistent with getuid(2), etc.) behaviour from getx?id() syscalls now. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Michael Cree <mcree@orcon.net.nz> Acked-by: Matt Turner <mattst88@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>