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2013-07-28lib/Kconfig.debug: Restrict FRAME_POINTER for MIPSMarkos Chandras
commit 25c87eae1725ed77a8b44d782a86abdc279b4ede upstream. FAULT_INJECTION_STACKTRACE_FILTER selects FRAME_POINTER but that symbol is not available for MIPS. Fixes the following problem on a randconfig: warning: (LOCKDEP && FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && KMEMCHECK) selects FRAME_POINTER which has unmet direct dependencies (DEBUG_KERNEL && (CRIS || M68K || FRV || UML || AVR32 || SUPERH || BLACKFIN || MN10300 || METAG) || ARCH_WANT_FRAME_POINTERS) Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Acked-by: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5441/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-30notifier-error-inject: fix module names in KconfigAkinobu Mita
The Kconfig help text for MEMORY_NOTIFIER_ERROR_INJECT and OF_RECONFIG_NOTIFIER_ERROR_INJECT has mismatched module names. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKSStephen Boyd
The help text for this config is duplicated across the x86, parisc, and s390 Kconfig.debug files. Arnd Bergman noted that the help text was slightly misleading and should be fixed to state that enabling this option isn't a problem when using pre 4.4 gcc. To simplify the rewording, consolidate the text into lib/Kconfig.debug and modify it there to be more explicit about when you should say N to this config. Also, make the text a bit more generic by stating that this option enables compile time checks so we can cover architectures which emit warnings vs. ones which emit errors. The details of how an architecture decided to implement the checks isn't as important as the concept of compile time checking of copy_from_user() calls. While we're doing this, remove all the copy_from_user_overflow() code that's duplicated many times and place it into lib/ so that any architecture supporting this option can get the function for free. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Helge Deller <deller@gmx.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30lib/string_helpers: introduce generic string_unescapeAndy Shevchenko
There are several places in kernel where modules unescapes input to convert C-Style Escape Sequences into byte codes. The patch provides generic implementation of such approach. Test cases are also included into the patch. [akpm@linux-foundation.org: clarify comment] [akpm@linux-foundation.org: export get_random_int() to modules] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: William Hubbs <w.d.hubbs@gmail.com> Cc: Chris Brannon <chris@the-brannons.com> Cc: Kirk Reiser <kirk@braille.uwo.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-03-03Merge tag 'metag-v3.9-rc1-v4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag Pull new ImgTec Meta architecture from James Hogan: "This adds core architecture support for Imagination's Meta processor cores, followed by some later miscellaneous arch/metag cleanups and fixes which I kept separate to ease review: - Support for basic Meta 1 (ATP) and Meta 2 (HTP) core architecture - A few fixes all over, particularly for symbol prefixes - A few privilege protection fixes - Several cleanups (setup.c includes, split out a lot of metag_ksyms.c) - Fix some missing exports - Convert hugetlb to use vm_unmapped_area() - Copy device tree to non-init memory - Provide dma_get_sgtable()" * tag 'metag-v3.9-rc1-v4' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag: (61 commits) metag: Provide dma_get_sgtable() metag: prom.h: remove declaration of metag_dt_memblock_reserve() metag: copy devicetree to non-init memory metag: cleanup metag_ksyms.c includes metag: move mm/init.c exports out of metag_ksyms.c metag: move usercopy.c exports out of metag_ksyms.c metag: move setup.c exports out of metag_ksyms.c metag: move kick.c exports out of metag_ksyms.c metag: move traps.c exports out of metag_ksyms.c metag: move irq enable out of irqflags.h on SMP genksyms: fix metag symbol prefix on crc symbols metag: hugetlb: convert to vm_unmapped_area() metag: export clear_page and copy_page metag: export metag_code_cache_flush_all metag: protect more non-MMU memory regions metag: make TXPRIVEXT bits explicit metag: kernel/setup.c: sort includes perf: Enable building perf tools for Meta metag: add boot time LNKGET/LNKSET check metag: add __init to metag_cache_probe() ...
2013-03-02Kconfig.debug: add METAG to dependency listsJames Hogan
Add [!]METAG to a couple of Kconfig dependencies in lib/Kconfig.debug. Don't allow stack utilization instrumentation on metag, and allow building with frame pointers. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Paul E. McKenney" <paul.mckenney@linaro.org> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Michel Lespinasse <walken@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com>
2013-02-21Merge branch 'akpm' (incoming from Andrew)Linus Torvalds
Merge misc patches from Andrew Morton: - Florian has vanished so I appear to have become fbdev maintainer again :( - Joel and Mark are distracted to welcome to the new OCFS2 maintainer - The backlight queue - Small core kernel changes - lib/ updates - The rtc queue - Various random bits * akpm: (164 commits) rtc: rtc-davinci: use devm_*() functions rtc: rtc-max8997: use devm_request_threaded_irq() rtc: rtc-max8907: use devm_request_threaded_irq() rtc: rtc-da9052: use devm_request_threaded_irq() rtc: rtc-wm831x: use devm_request_threaded_irq() rtc: rtc-tps80031: use devm_request_threaded_irq() rtc: rtc-lp8788: use devm_request_threaded_irq() rtc: rtc-coh901331: use devm_clk_get() rtc: rtc-vt8500: use devm_*() functions rtc: rtc-tps6586x: use devm_request_threaded_irq() rtc: rtc-imxdi: use devm_clk_get() rtc: rtc-cmos: use dev_warn()/dev_dbg() instead of printk()/pr_debug() rtc: rtc-pcf8583: use dev_warn() instead of printk() rtc: rtc-sun4v: use pr_warn() instead of printk() rtc: rtc-vr41xx: use dev_info() instead of printk() rtc: rtc-rs5c313: use pr_err() instead of printk() rtc: rtc-at91rm9200: use dev_dbg()/dev_err() instead of printk()/pr_debug() rtc: rtc-rs5c372: use dev_dbg()/dev_warn() instead of printk()/pr_debug() rtc: rtc-ds2404: use dev_err() instead of printk() rtc: rtc-efi: use dev_err()/dev_warn()/pr_err() instead of printk() ...
2013-02-21lib/Kconfig.debug: unhide CONFIG_PANIC_ON_OOPSKyle McMartin
CONFIG_EXPERT doesn't really make sense, and hides it unintentionally. Remove superfluous "default n" pointed out by Ingo as well. Signed-off-by: Kyle McMartin <kyle@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21Merge tag 'driver-core-3.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core patches from Greg Kroah-Hartman: "Here is the big driver core merge for 3.9-rc1 There are two major series here, both of which touch lots of drivers all over the kernel, and will cause you some merge conflicts: - add a new function called devm_ioremap_resource() to properly be able to check return values. - remove CONFIG_EXPERIMENTAL Other than those patches, there's not much here, some minor fixes and updates" Fix up trivial conflicts * tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (221 commits) base: memory: fix soft/hard_offline_page permissions drivercore: Fix ordering between deferred_probe and exiting initcalls backlight: fix class_find_device() arguments TTY: mark tty_get_device call with the proper const values driver-core: constify data for class_find_device() firmware: Ignore abort check when no user-helper is used firmware: Reduce ifdef CONFIG_FW_LOADER_USER_HELPER firmware: Make user-mode helper optional firmware: Refactoring for splitting user-mode helper code Driver core: treat unregistered bus_types as having no devices watchdog: Convert to devm_ioremap_resource() thermal: Convert to devm_ioremap_resource() spi: Convert to devm_ioremap_resource() power: Convert to devm_ioremap_resource() mtd: Convert to devm_ioremap_resource() mmc: Convert to devm_ioremap_resource() mfd: Convert to devm_ioremap_resource() media: Convert to devm_ioremap_resource() iommu: Convert to devm_ioremap_resource() drm: Convert to devm_ioremap_resource() ...
2013-02-04Merge branch 'rcu/next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: 1. Changes to rcutorture and to RCU documentation. Posted to LKML at https://lkml.org/lkml/2013/1/26/188. 2. Enhancements to uniprocessor handling in tiny RCU. Posted to LKML at https://lkml.org/lkml/2013/1/27/2. 3. Tag RCU callbacks with grace-period number to simplify callback advancement. Posted to LKML at https://lkml.org/lkml/2013/1/26/203. 4. Miscellaneous fixes. Posted to LKML at https://lkml.org/lkml/2013/1/26/204. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-28Merge branches 'doctorture.2013.01.29a', 'fixes.2013.01.26a', ↵Paul E. McKenney
'tagcb.2013.01.24a' and 'tiny.2013.01.29b' into HEAD doctorture.2013.01.11a: Changes to rcutorture and to RCU documentation. fixes.2013.01.26a: Miscellaneous fixes. tagcb.2013.01.24a: Tag RCU callbacks with grace-period number to simplify callback advancement. tiny.2013.01.29b: Enhancements to uniprocessor handling in tiny RCU.
2013-01-28rcu: Provide RCU CPU stall warnings for tiny RCUPaul E. McKenney
Tiny RCU has historically omitted RCU CPU stall warnings in order to reduce memory requirements, however, lack of these warnings caused Thomas Gleixner some debugging pain recently. Therefore, this commit adds RCU CPU stall warnings to tiny RCU if RCU_TRACE=y. This keeps the memory footprint small, while still enabling CPU stall warnings in kernels built to enable them. Updated to include Josh Triplett's suggested use of RCU_STALL_COMMON config variable to simplify #if expressions. Reported-by: Thomas Gleixner <tglx@linutronix.de> 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>
2013-01-26rcu: Consolidate debugging Kconfig optionsDave Hansen
The RCU-related debugging Kconfig options are in two different places, and consume too much screen real estate. This commit therefore consolidates them into their own menu. Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-01-17lib: remove depends on CONFIG_EXPERIMENTALKees Cook
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a while now and is almost always enabled by default. As agreed during the Linux kernel summit, remove it from any "depends on" lines in Kconfigs. CC: Andrew Morton <akpm@linux-foundation.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> CC: Dmitry Kasatkin <dmitry.kasatkin@intel.com> CC: James Morris <james.l.morris@oracle.com> CC: "Michael S. Tsirkin" <mst@redhat.com> CC: Akinobu Mita <akinobu.mita@gmail.com> CC: Ingo Molnar <mingo@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-08rcu: Reduce rcutorture tracingPaul E. McKenney
Currently, rcutorture traces every read-side access. This can be problematic because even a two-minute rcutorture run on a two-CPU system can generate 28,853,363 reads. Normally, only a failing read is of interest, so this commit traces adjusts rcutorture's tracing to only trace failing reads. The resulting event tracing records the time and the ->completed value captured at the beginning of the RCU read-side critical section, allowing correlation with other event-tracing messages. 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> [ paulmck: Add fix to build problem located by Randy Dunlap based on diagnosis by Steven Rostedt. ]
2013-01-03misc: remove __dev* attributes.Greg Kroah-Hartman
CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the last of the __dev* markings from the kernel from a variety of different, tiny, places. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-12-18Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull powerpc update from Benjamin Herrenschmidt: "The main highlight is probably some base POWER8 support. There's more to come such as transactional memory support but that will wait for the next one. Overall it's pretty quiet, or rather I've been pretty poor at picking things up from patchwork and reviewing them this time around and Kumar no better on the FSL side it seems..." * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (73 commits) powerpc+of: Rename and fix OF reconfig notifier error inject module powerpc: mpc5200: Add a3m071 board support powerpc/512x: don't compile any platform DIU code if the DIU is not enabled powerpc/mpc52xx: use module_platform_driver macro powerpc+of: Export of_reconfig_notifier_[register,unregister] powerpc/dma/raidengine: add raidengine device powerpc/iommu/fsl: Add PAMU bypass enable register to ccsr_guts struct powerpc/mpc85xx: Change spin table to cached memory powerpc/fsl-pci: Add PCI controller ATMU PM support powerpc/86xx: fsl_pcibios_fixup_bus requires CONFIG_PCI drivers/virt: the Freescale hypervisor driver doesn't need to check MSR[GS] powerpc/85xx: p1022ds: Use NULL instead of 0 for pointers powerpc: Disable relocation on exceptions when kexecing powerpc: Enable relocation on during exceptions at boot powerpc: Move get_longbusy_msecs into hvcall.h and remove duplicate function powerpc: Add wrappers to enable/disable relocation on exceptions powerpc: Add set_mode hcall powerpc: Setup relocation on exceptions for bare metal systems powerpc: Move initial mfspr LPCR out of __init_LPCR powerpc: Add relocation on exception vector handlers ...
2012-12-14powerpc+of: Rename and fix OF reconfig notifier error inject moduleBenjamin Herrenschmidt
This module used to inject errors in the pSeries specific dynamic reconfiguration notifiers. Those are gone however, replaced by generic notifiers for changes to the device-tree. So let's update the module to deal with these instead and rename it along the way. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Akinobu Mita <akinobu.mita@gmail.com>
2012-12-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial branch from Jiri Kosina: "Usual stuff -- comment/printk typo fixes, documentation updates, dead code elimination." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits) HOWTO: fix double words typo x86 mtrr: fix comment typo in mtrr_bp_init propagate name change to comments in kernel source doc: Update the name of profiling based on sysfs treewide: Fix typos in various drivers treewide: Fix typos in various Kconfig wireless: mwifiex: Fix typo in wireless/mwifiex driver messages: i2o: Fix typo in messages/i2o scripts/kernel-doc: check that non-void fcts describe their return value Kernel-doc: Convention: Use a "Return" section to describe return values radeon: Fix typo and copy/paste error in comments doc: Remove unnecessary declarations from Documentation/accounting/getdelays.c various: Fix spelling of "asynchronous" in comments. Fix misspellings of "whether" in comments. eisa: Fix spelling of "asynchronous". various: Fix spelling of "registered" in comments. doc: fix quite a few typos within Documentation target: iscsi: fix comment typos in target/iscsi drivers treewide: fix typo of "suport" in various comments and Kconfig treewide: fix typo of "suppport" in various comments ...
2012-12-03treewide: Fix typos in various KconfigMasanari Iida
Correct spelling typo within various Kconfig. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-11-13rcu: Reduce default RCU CPU stall warning timeoutPaul E. McKenney
The RCU CPU stall warning timeout has defaulted to 60 seconds for some years, with almost no false positives. This commit therefore reduces the default to 21 seconds, slightly shorter than the new soft-lockup timeout. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-10-09mm: add CONFIG_DEBUG_VM_RB build optionMichel Lespinasse
Add a CONFIG_DEBUG_VM_RB build option for the previously existing DEBUG_MM_RB code. Now that Andi Kleen modified it to avoid using recursive algorithms, we can expose it a bit more. Also extend this code to validate_mm() after stack expansion, and to check that the vma's start and last pgoffs have not changed since the nodes were inserted on the anon vma interval tree (as it is important that the nodes be reindexed after each such update). Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09prio_tree: removeMichel Lespinasse
After both prio_tree users have been converted to use red-black trees, there is no need to keep around the prio tree library anymore. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: add prio tree and interval tree testsMichel Lespinasse
Patch 1 implements support for interval trees, on top of the augmented rbtree API. It also adds synthetic tests to compare the performance of interval trees vs prio trees. Short answers is that interval trees are slightly faster (~25%) on insert/erase, and much faster (~2.4 - 3x) on search. It is debatable how realistic the synthetic test is, and I have not made such measurements yet, but my impression is that interval trees would still come out faster. Patch 2 uses a preprocessor template to make the interval tree generic, and uses it as a replacement for the vma prio_tree. Patch 3 takes the other prio_tree user, kmemleak, and converts it to use a basic rbtree. We don't actually need the augmented rbtree support here because the intervals are always non-overlapping. Patch 4 removes the now-unused prio tree library. Patch 5 proposes an additional optimization to rb_erase_augmented, now providing it as an inline function so that the augmented callbacks can be inlined in. This provides an additional 5-10% performance improvement for the interval tree insert/erase benchmark. There is a maintainance cost as it exposes augmented rbtree users to some of the rbtree library internals; however I think this cost shouldn't be too high as I expect the augmented rbtree will always have much less users than the base rbtree. I should probably add a quick summary of why I think it makes sense to replace prio trees with augmented rbtree based interval trees now. One of the drivers is that we need augmented rbtrees for Rik's vma gap finding code, and once you have them, it just makes sense to use them for interval trees as well, as this is the simpler and more well known algorithm. prio trees, in comparison, seem *too* clever: they impose an additional 'heap' constraint on the tree, which they use to guarantee a faster worst-case complexity of O(k+log N) for stabbing queries in a well-balanced prio tree, vs O(k*log N) for interval trees (where k=number of matches, N=number of intervals). Now this sounds great, but in practice prio trees don't realize this theorical benefit. First, the additional constraint makes them harder to update, so that the kernel implementation has to simplify things by balancing them like a radix tree, which is not always ideal. Second, the fact that there are both index and heap properties makes both tree manipulation and search more complex, which results in a higher multiplicative time constant. As it turns out, the simple interval tree algorithm ends up running faster than the more clever prio tree. This patch: Add two test modules: - prio_tree_test measures the performance of lib/prio_tree.c, both for insertion/removal and for stabbing searches - interval_tree_test measures the performance of a library of equivalent functionality, built using the augmented rbtree support. In order to support the second test module, lib/interval_tree.c is introduced. It is kept separate from the interval_tree_test main file for two reasons: first we don't want to provide an unfair advantage over prio_tree_test by having everything in a single compilation unit, and second there is the possibility that the interval tree functionality could get some non-test users in kernel over time. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: performance and correctness testMichel Lespinasse
This small module helps measure the performance of rbtree insert and erase. Additionally, we run a few correctness tests to check that the rbtrees have all desired properties: - contains the right number of nodes in the order desired, - never two consecutive red nodes on any path, - all paths to leaf nodes have the same number of black nodes, - root node is black [akpm@linux-foundation.org: fix printk warning: sparc64 cycles_t is unsigned long] Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09Kconfig: clean up the long arch list for the DEBUG_BUGVERBOSE config optionCatalin Marinas
Introduce HAVE_DEBUG_BUGVERBOSE config option and select it in corresponding architecture Kconfig files. Architectures that already select GENERIC_BUG don't need to select HAVE_DEBUG_BUGVERBOSE. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: David Howells <dhowells@redhat.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09Kconfig: clean up the long arch list for the DEBUG_KMEMLEAK config optionCatalin Marinas
Introduce HAVE_DEBUG_KMEMLEAK config option and select it in corresponding architecture Kconfig files. DEBUG_KMEMLEAK now only depends on HAVE_DEBUG_KMEMLEAK. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> 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: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06lib/Kconfig.debug: adjust hard-lockup related Kconfig optionsJan Beulich
The main option should not appear in the resulting .config when the dependencies aren't met (i.e. use "depends on" rather than directly setting the default from the combined dependency values). The sub-options should depend on the main option rather than a more generic higher level one. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 ...
2012-09-23rcu: Add PROVE_RCU_DELAY to provoke difficult racesPaul E. McKenney
There have been some recent bugs that were triggered only when preemptible RCU's __rcu_read_unlock() was preempted just after setting ->rcu_read_lock_nesting to INT_MIN, which is a low-probability event. Therefore, reproducing those bugs (to say nothing of gaining confidence in alleged fixes) was quite difficult. This commit therefore creates a new debug-only RCU kernel config option that forces a short delay in __rcu_read_unlock() to increase the probability of those sorts of bugs occurring. 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>
2012-09-17arm64: Build infrastructureCatalin Marinas
This patch adds Makefile and Kconfig files required for building an AArch64 kernel. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-07-30powerpc: pSeries reconfig notifier error injection moduleAkinobu Mita
This provides the ability to inject artifical errors to pSeries reconfig notifier chain callbacks. It is controlled through debugfs interface under /sys/kernel/debug/notifier-error-inject/pSeries-reconfig If the notifier call chain should be failed with some events notified, write the error code to "actions/<notifier event>/error". Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30memory: memory notifier error injection moduleAkinobu Mita
This provides the ability to inject artifical errors to memory hotplug notifier chain callbacks. It is controlled through debugfs interface under /sys/kernel/debug/notifier-error-inject/memory If the notifier call chain should be failed with some events notified, write the error code to "actions/<notifier event>/error". Example: Inject memory hotplug offline error (-12 == -ENOMEM) # cd /sys/kernel/debug/notifier-error-inject/memory # echo -12 > actions/MEM_GOING_OFFLINE/error # echo offline > /sys/devices/system/memory/memoryXXX/state bash: echo: write error: Cannot allocate memory Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30PM: PM notifier error injection moduleAkinobu Mita
This provides the ability to inject artifical errors to PM notifier chain callbacks. It is controlled through debugfs interface under /sys/kernel/debug/notifier-error-inject/pm Each of the files in "error" directory represents an event which can be failed and contains the error code. If the notifier call chain should be failed with some events notified, write the error code to the files. If the notifier call chain should be failed with some events notified, write the error code to "actions/<notifier event>/error". Example: Inject PM suspend error (-12 = -ENOMEM) # cd /sys/kernel/debug/notifier-error-inject/pm # echo -12 > actions/PM_SUSPEND_PREPARE/error # echo mem > /sys/power/state bash: echo: write error: Cannot allocate memory Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Pavel Machek <pavel@ucw.cz> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30cpu: rewrite cpu-notifier-error-inject moduleAkinobu Mita
Rewrite existing cpu-notifier-error-inject module to use debugfs based new framework. This change removes cpu_up_prepare_error and cpu_down_prepare_error module parameters which were used to specify error code to be injected. We could keep these module parameters for backward compatibility by module_param_cb but it seems overkill for this module. This provides the ability to inject artifical errors to CPU notifier chain callbacks. It is controlled through debugfs interface under /sys/kernel/debug/notifier-error-inject/cpu If the notifier call chain should be failed with some events notified, write the error code to "actions/<notifier event>/error". Example1: inject CPU offline error (-1 == -EPERM) # cd /sys/kernel/debug/notifier-error-inject/cpu # echo -1 > actions/CPU_DOWN_PREPARE/error # echo 0 > /sys/devices/system/cpu/cpu1/online bash: echo: write error: Operation not permitted Example2: inject CPU online error (-2 == -ENOENT) # cd /sys/kernel/debug/notifier-error-inject/cpu # echo -2 > actions/CPU_UP_PREPARE/error # echo 1 > /sys/devices/system/cpu/cpu1/online bash: echo: write error: No such file or directory Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30fault-injection: notifier error injectionAkinobu Mita
This patchset provides kernel modules that can be used to test the error handling of notifier call chain failures by injecting artifical errors to the following notifier chain callbacks. * CPU notifier * PM notifier * memory hotplug notifier * powerpc pSeries reconfig notifier Example: Inject CPU offline error (-1 == -EPERM) # cd /sys/kernel/debug/notifier-error-inject/cpu # echo -1 > actions/CPU_DOWN_PREPARE/error # echo 0 > /sys/devices/system/cpu/cpu1/online bash: echo: write error: Operation not permitted The patchset also adds cpu and memory hotplug tests to tools/testing/selftests These tests first do simple online and offline test and then do fault injection tests if notifier error injection module is available. This patch: The notifier error injection provides the ability to inject artifical errors to specified notifier chain callbacks. It is useful to test the error handling of notifier call chain failures. This adds common basic functions to define which type of events can be fail and to initialize the debugfs interface to control what error code should be returned and which event should be failed. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-23Merge tag 'please-pull-misc-3.6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux Pull misc Itanium fixes from Tony Luck. * tag 'please-pull-misc-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux: debug: Do not permit CONFIG_DEBUG_STACK_USAGE=y on IA64 or PARISC [IA64] Port OOM changes to ia64_do_page_fault
2012-07-19debug: Do not permit CONFIG_DEBUG_STACK_USAGE=y on IA64 or PARISCTony Luck
The stack_not_used() function in <linux/sched.h> assumes that stacks grow downwards. This is not true on IA64 or PARISC, so this function would walk off in the wrong direction and into the weeds. Found on IA64 because of a compilation failure with recursive dependencies on IA64_TASKSIZE and IA64_THREAD_INFO_SIZE. Fixing the code is possible, but should be combined with other infrastructure additions to set up the "canary" at the end of the stack. Reported-by: Fengguang Wu <fengguang.wu@intel.com> (failed allmodconfig build) Signed-off-by: Tony Luck <tony.luck@intel.com>
2012-06-06Merge branch 'core/debug' into core/urgentIngo Molnar
Merge two debugging patchlets that were waiting for preparatory commits to hit upstream. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-23Merge branches 'x86-asm-for-linus', 'x86-cleanups-for-linus', ↵Linus Torvalds
'x86-cpu-for-linus', 'x86-debug-for-linus' and 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull initial trivial x86 stuff from Ingo Molnar. Various random cleanups and trivial fixes. * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86-64: Eliminate dead ia32 syscall handlers * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/pci-calgary_64.c: Remove obsoleted simple_strtoul() usage x86: Don't continue booting if we can't load the specified initrd x86: kernel/dumpstack.c simple_strtoul cleanup x86: kernel/check.c simple_strtoul cleanup debug: Add CONFIG_READABLE_ASM x86: spinlock.h: Remove REG_PTR_MODE * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cache_info: Fix setup of l2/l3 ids * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Avoid double stack traces with show_regs() * 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, microcode: microcode_core.c simple_strtoul cleanup
2012-05-09printk() - restore timestamp printing at console outputKay Sievers
The output of the timestamps got lost with the conversion of the kmsg buffer to records; restore the old behavior. Document, that CONFIG_PRINTK_TIME now only controls the output of the timestamps in the syslog() system call and on the console, and not the recording of the timestamps. Cc: Joe Perches <joe@perches.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sasha Levin <levinsasha928@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Reported-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-07panic: Make panic_on_oops configurableKyle McMartin
Several distros set this by default by patching panic_on_oops. It seems to fit with the BOOTPARAM_{HARD,SOFT}_PANIC options though, so let's add a Kconfig entry and reduce some more upstream delta. Signed-off-by: Kyle McMartin <kyle@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20120411121529.GH26688@redacted.bos.redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-04-30dynamic_debug: update Documentation/*, Kconfig.debugJim Cromie
In dynamic-debug-howto.txt: - add section: Debug Messages at Module Initialization Time - update flags indicators in example outputs to include '=' - make flags descriptions tabular - add item on '_' flag-char - add dyndbg, boot-args examples - rewrap some paragraphs with long lines In Kconfig.debug, note that compiling with -DDEBUG enables all pr_debug()s in that code. In kernel-parameters.txt, add dyndbg and module.dyndbg items, and deprecate ddebug_query. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-30debug: Add CONFIG_READABLE_ASMAndi Kleen
Add a config option to disable various gcc compiler optimizations that make assembler listings much harder to read. This is everything that reorders code significantly or creates partial functions. This is mainly to keep kernel hackers sane. Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1332960678-11879-2-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-03-29Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 updates from Ingo Molnar. This touches some non-x86 files due to the sanitized INLINE_SPIN_UNLOCK config usage. Fixed up trivial conflicts due to just header include changes (removing headers due to cpu_idle() merge clashing with the <asm/system.h> split). * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/amd: Be more verbose about LVT offset assignments x86, tls: Off by one limit check x86/ioapic: Add io_apic_ops driver layer to allow interception x86/olpc: Add debugfs interface for EC commands x86: Merge the x86_32 and x86_64 cpu_idle() functions x86/kconfig: Remove CONFIG_TR=y from the defconfigs x86: Stop recursive fault in print_context_stack after stack overflow x86/io_apic: Move and reenable irq only when CONFIG_GENERIC_PENDING_IRQ=y x86/apic: Add separate apic_id_valid() functions for selected apic drivers locking/kconfig: Simplify INLINE_SPIN_UNLOCK usage x86/kconfig: Update defconfigs x86: Fix excessive MSR print out when show_msr is not specified
2012-03-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctlLinus Torvalds
Pull sysctl updates from Eric Biederman: - Rewrite of sysctl for speed and clarity. Insert/remove/Lookup in sysctl are all now O(NlogN) operations, and are no longer bottlenecks in the process of adding and removing network devices. sysctl is now focused on being a filesystem instead of system call and the code can all be found in fs/proc/proc_sysctl.c. Hopefully this means the code is now approachable. Much thanks is owed to Lucian Grinjincu for keeping at this until something was found that was usable. - The recent proc_sys_poll oops found by the fuzzer during hibernation is fixed. * git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl: (36 commits) sysctl: protect poll() in entries that may go away sysctl: Don't call sysctl_follow_link unless we are a link. sysctl: Comments to make the code clearer. sysctl: Correct error return from get_subdir sysctl: An easier to read version of find_subdir sysctl: fix memset parameters in setup_sysctl_set() sysctl: remove an unused variable sysctl: Add register_sysctl for normal sysctl users sysctl: Index sysctl directories with rbtrees. sysctl: Make the header lists per directory. sysctl: Move sysctl_check_dups into insert_header sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy sysctl: Replace root_list with links between sysctl_table_sets. sysctl: Add sysctl_print_dir and use it in get_subdir sysctl: Stop requiring explicit management of sysctl directories sysctl: Add a root pointer to ctl_table_set sysctl: Rewrite proc_sys_readdir in terms of first_entry and next_entry sysctl: Rewrite proc_sys_lookup introducing find_entry and lookup_entry. sysctl: Normalize the root_table data structure. sysctl: Factor out insert_header and erase_header ...
2012-03-23nmi watchdog: do not use cpp symbol in KconfigCong Wang
ARCH_HAS_NMI_WATCHDOG is a macro defined by arch, but config HARDLOCKUP_DETECTOR depends on it. This is wrong, ARCH_HAS_NMI_WATCHDOG has to be a Kconfig config, and arch's need it should select it explicitly. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Acked-by: Don Zickus <dzickus@redhat.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Cc: David Howells <dhowells@redhat.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23locking/kconfig: Simplify INLINE_SPIN_UNLOCK usageRaghavendra K T
Get rid of INLINE_SPIN_UNLOCK entirely replacing it with UNINLINE_SPIN_UNLOCK instead of the reverse meaning. Whoever wants to change the default spinlock inlining behavior and uninline the spinlocks for some weird reason, such as spinlock debugging, paravirt etc. can now all just select UNINLINE_SPIN_UNLOCK Original discussion at: https://lkml.org/lkml/2012/3/21/357 Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: linux-mips@linux-mips.org Link: http://lkml.kernel.org/r/20120322095502.30866.75756.sendpatchset@codeblue [ tidied up the changelog a bit ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-03-20Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf events changes for v3.4 from Ingo Molnar: - New "hardware based branch profiling" feature both on the kernel and the tooling side, on CPUs that support it. (modern x86 Intel CPUs with the 'LBR' hardware feature currently.) This new feature is basically a sophisticated 'magnifying glass' for branch execution - something that is pretty difficult to extract from regular, function histogram centric profiles. The simplest mode is activated via 'perf record -b', and the result looks like this in perf report: $ perf record -b any_call,u -e cycles:u branchy $ perf report -b --sort=symbol 52.34% [.] main [.] f1 24.04% [.] f1 [.] f3 23.60% [.] f1 [.] f2 0.01% [k] _IO_new_file_xsputn [k] _IO_file_overflow 0.01% [k] _IO_vfprintf_internal [k] _IO_new_file_xsputn 0.01% [k] _IO_vfprintf_internal [k] strchrnul 0.01% [k] __printf [k] _IO_vfprintf_internal 0.01% [k] main [k] __printf This output shows from/to branch columns and shows the highest percentage (from,to) jump combinations - i.e. the most likely taken branches in the system. "branches" can also include function calls and any other synchronous and asynchronous transitions of the instruction pointer that are not 'next instruction' - such as system calls, traps, interrupts, etc. This feature comes with (hopefully intuitive) flat ascii and TUI support in perf report. - Various 'perf annotate' visual improvements for us assembly junkies. It will now recognize function calls in the TUI and by hitting enter you can follow the call (recursively) and back, amongst other improvements. - Multiple threads/processes recording support in perf record, perf stat, perf top - which is activated via a comma-list of PIDs: perf top -p 21483,21485 perf stat -p 21483,21485 -ddd perf record -p 21483,21485 - Support for per UID views, via the --uid paramter to perf top, perf report, etc. For example 'perf top --uid mingo' will only show the tasks that I am running, excluding other users, root, etc. - Jump label restructurings and improvements - this includes the factoring out of the (hopefully much clearer) include/linux/static_key.h generic facility: struct static_key key = STATIC_KEY_INIT_FALSE; ... if (static_key_false(&key)) do unlikely code else do likely code ... static_key_slow_inc(); ... static_key_slow_inc(); ... The static_key_false() branch will be generated into the code with as little impact to the likely code path as possible. the static_key_slow_*() APIs flip the branch via live kernel code patching. This facility can now be used more widely within the kernel to micro-optimize hot branches whose likelihood matches the static-key usage and fast/slow cost patterns. - SW function tracer improvements: perf support and filtering support. - Various hardenings of the perf.data ABI, to make older perf.data's smoother on newer tool versions, to make new features integrate more smoothly, to support cross-endian recording/analyzing workflows better, etc. - Restructuring of the kprobes code, the splitting out of 'optprobes', and a corner case bugfix. - Allow the tracing of kernel console output (printk). - Improvements/fixes to user-space RDPMC support, allowing user-space self-profiling code to extract PMU counts without performing any system calls, while playing nice with the kernel side. - 'perf bench' improvements - ... and lots of internal restructurings, cleanups and fixes that made these features possible. And, as usual this list is incomplete as there were also lots of other improvements * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits) perf report: Fix annotate double quit issue in branch view mode perf report: Remove duplicate annotate choice in branch view mode perf/x86: Prettify pmu config literals perf report: Enable TUI in branch view mode perf report: Auto-detect branch stack sampling mode perf record: Add HEADER_BRANCH_STACK tag perf record: Provide default branch stack sampling mode option perf tools: Make perf able to read files from older ABIs perf tools: Fix ABI compatibility bug in print_event_desc() perf tools: Enable reading of perf.data files from different ABI rev perf: Add ABI reference sizes perf report: Add support for taken branch sampling perf record: Add support for sampling taken branch perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK x86/kprobes: Split out optprobe related code to kprobes-opt.c x86/kprobes: Fix a bug which can modify kernel code permanently x86/kprobes: Fix instruction recovery on optimized path perf: Add callback to flush branch_stack on context switch perf: Disable PERF_SAMPLE_BRANCH_* when not supported perf/x86: Add LBR software filter support for Intel CPUs ...
2012-02-21rcu: Print scheduling-clock information on RCU CPU stall-warning messagesPaul E. McKenney
There have been situations where RCU CPU stall warnings were caused by issues in scheduling-clock timer initialization. To make it easier to track these down, this commit causes the RCU CPU stall-warning messages to print out the number of scheduling-clock interrupts taken in the current grace period for each stalled CPU. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>