aboutsummaryrefslogtreecommitdiff
path: root/lib
AgeCommit message (Collapse)Author
2013-07-04Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "The usual stuff from trivial tree" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits) treewide: relase -> release Documentation/cgroups/memory.txt: fix stat file documentation sysctl/net.txt: delete reference to obsolete 2.4.x kernel spinlock_api_smp.h: fix preprocessor comments treewide: Fix typo in printk doc: device tree: clarify stuff in usage-model.txt. open firmware: "/aliasas" -> "/aliases" md: bcache: Fixed a typo with the word 'arithmetic' irq/generic-chip: fix a few kernel-doc entries frv: Convert use of typedef ctl_table to struct ctl_table sgi: xpc: Convert use of typedef ctl_table to struct ctl_table doc: clk: Fix incorrect wording Documentation/arm/IXP4xx fix a typo Documentation/networking/ieee802154 fix a typo Documentation/DocBook/media/v4l fix a typo Documentation/video4linux/si476x.txt fix a typo Documentation/virtual/kvm/api.txt fix a typo Documentation/early-userspace/README fix a typo Documentation/video4linux/soc-camera.txt fix a typo lguest: fix CONFIG_PAE -> CONFIG_x86_PAE in comment ...
2013-07-04Merge branch 'kconfig-diet' from Dave HansenLinus Torvalds
Merge Kconfig menu diet patches from Dave Hansen: "I think the "Kernel Hacking" menu has gotten a bit out of hand. It is over 120 lines long on my system with everything enabled and options are scattered around it haphazardly. http://sr71.net/~dave/linux/kconfig-horror.png Let's try to introduce some sanity. This set takes that 120 lines down to 55 and makes it vastly easier to find some things. It's a start. This set stands on its own, but there is plenty of room for follow-up patches. The arch-specific debug options still end up getting stuck in the top-level "kernel hacking" menu. OPTIMIZE_INLINING, for instance, could obviously go in to the "compiler options" menu, but the fact that it is defined in arch/ in a separate Kconfig file keeps it on its own for the moment. The Signed-off-by's in here look funky. I changed employers while working on this set, so I have signoffs from both email addresses" * emailed patches from Dave Hansen <dave@sr71.net>: hang and lockup detection menu kconfig: consolidate printk options group locking debugging options consolidate compilation option configs consolidate runtime testing configs order memory debugging Kconfig options consolidate per-arch stack overflow debugging options
2013-07-04hang and lockup detection menuDave Hansen
The hard/softlockup and hung-task entries take up 6 lines of screen real-estate when enabled. I bet folks don't mess with these _that_ often, so move them in a group down a level. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04kconfig: consolidate printk optionsDave Hansen
Same deal, take the printk-related things and hide them in a menu. This takes another 4 items out of the top-level menu. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04group locking debugging optionsDave Hansen
Original posting: http://lkml.kernel.org/r/20121214184208.D9E5804D@kernel.stglabs.ibm.com There are quite a few of these, and we want to make sure that there is one-stop-shopping for lock debugging. Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04consolidate compilation option configsDave Hansen
Original Post: http://lkml.kernel.org/r/20121214184207.6E00DDEC@kernel.stglabs.ibm.com Again, trying to come up with some common themes of the stuff in the kernel hacking menu... There are quite a few options to tweak compilation in some way, or perform extra compile-time checks. Give them their own menu. The diff here looks a bit funny... makes it look like I'm moving debugfs even though I'm actually moving the options on either side of it. Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04consolidate runtime testing configsDave Hansen
Original posting: http://lkml.kernel.org/r/20121214184206.FC11422F@kernel.stglabs.ibm.com These runtime tests are great, except that there are a lot of them, and they are very rarely needed. Give them their own menu so that only the folks who need them will have to go looking for them. Note that there are some other runtime tests that are not in here, like for RCU or locking. This menu should only be used for tests that do not have a more appropriate home. Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04order memory debugging Kconfig optionsDave Hansen
Original posting: http://lkml.kernel.org/r/20121214184203.37E6C724@kernel.stglabs.ibm.com There are a *LOT* of memory debugging options. They are just scattered all over the "Kernel Hacking" menu. Sure, "memory debugging" is a very vague term and it's going to be hard to make absolute rules about what goes in here, but this has to be better than what we had before. This does, however, leave out the architecture-specific memory debugging options (like x86's DEBUG_SET_MODULE_RONX). There would need to be some substantial changes to move those in here. Kconfig can not easily mix arch-specific and generic options together: it really requires a file per-architecture, and I think having an arch/foo/Kconfig.debug-memory might be taking things a bit too far Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04consolidate per-arch stack overflow debugging optionsDave Hansen
Original posting: http://lkml.kernel.org/r/20121214184202.F54094D9@kernel.stglabs.ibm.com Several architectures have similar stack debugging config options. They all pretty much do the same thing, some with slightly differing help text. This patch changes the architectures to instead enable a Kconfig boolean, and then use that boolean in the generic Kconfig.debug to present the actual menu option. This removes a bunch of duplication and adds consistency across arches. Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Reviewed-by: H. Peter Anvin <hpa@zytor.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [for tile] Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03Merge branch 'akpm' (updates from Andrew Morton)Linus Torvalds
Merge first patch-bomb from Andrew Morton: - various misc bits - I'm been patchmonkeying ocfs2 for a while, as Joel and Mark have been distracted. There has been quite a bit of activity. - About half the MM queue - Some backlight bits - Various lib/ updates - checkpatch updates - zillions more little rtc patches - ptrace - signals - exec - procfs - rapidio - nbd - aoe - pps - memstick - tools/testing/selftests updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (445 commits) tools/testing/selftests: don't assume the x bit is set on scripts selftests: add .gitignore for kcmp selftests: fix clean target in kcmp Makefile selftests: add .gitignore for vm selftests: add hugetlbfstest self-test: fix make clean selftests: exit 1 on failure kernel/resource.c: remove the unneeded assignment in function __find_resource aio: fix wrong comment in aio_complete() drivers/w1/slaves/w1_ds2408.c: add magic sequence to disable P0 test mode drivers/memstick/host/r592.c: convert to module_pci_driver drivers/memstick/host/jmb38x_ms: convert to module_pci_driver pps-gpio: add device-tree binding and support drivers/pps/clients/pps-gpio.c: convert to module_platform_driver drivers/pps/clients/pps-gpio.c: convert to devm_* helpers drivers/parport/share.c: use kzalloc Documentation/accounting/getdelays.c: avoid strncpy in accounting tool aoe: update internal version number to v83 aoe: update copyright date aoe: perform I/O completions in parallel ...
2013-07-03idr: print a stack dump after ida_remove warningJean Delvare
We print a dump stack after idr_remove warning. This is useful to find the faulty piece of code. Let's do the same for ida_remove, as it would be equally useful there. [akpm@linux-foundation.org: convert the open-coded printk+dump_stack into WARN()] Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Tejun Heo <tj@kernel.org> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03lib/percpu_counter.c: __this_cpu_write() doesn't need to be protected by ↵Fan Du
spinlock __this_cpu_write doesn't need to be protected by spinlock, AS we are doing per cpu write with preempt disabled. And another reason to remove __this_cpu_write outside of spinlock: __percpu_counter_sum is not an accurate counter. Signed-off-by: Fan Du <fan.du@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03dump_stack: serialize the output from dump_stack()Alex Thorlton
Add functionality to serialize the output from dump_stack() to avoid mangling of the output when dump_stack is called simultaneously from multiple cpus. [akpm@linux-foundation.org: fix comment indenting, avoid inclusion of <asm/> files - use <linux/> where possiblem fix uniprocessor build (__dump_stack undefined), remove unneeded ifdef around smp.h inclusion] Signed-off-by: Alex Thorlton <athorlton@sgi.com> Reported-by: Russ Anderson <rja@sgi.com> Reviewed-by: Robin Holt <holt@sgi.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: David S. Miller <davem@davemloft.net> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03Merge branch 'exotic-arch-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k Pull "exotic" arch fixes from Geert Uytterhoeven: "This is a collection of several exotic architecture fixes, and a few other fixes for issues that were detected while doing the former" * 'exotic-arch-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: (35 commits) lib: Move fonts from drivers/video/console/ to lib/fonts/ console/font: Refactor font support code selection logic Revert "staging/solo6x10: depend on CONFIG_FONTS" input: cros_ec_keyb_clear_keyboard() depends on CONFIG_PM_SLEEP score: Wire up asm-generic/xor.h score: Remove unneeded <asm/dma-mapping.h> openrisc: Wire up asm-generic/xor.h h8300/boot: Use POSIX "$((..))" instead of bashism "$[...]" h8300: Mark H83002 and H83048 CPU support broken h8300: Switch h8300 to drivers/Kconfig h8300: Limit timer channel ranges in Kconfig h8300: Wire up asm-generic/xor.h h8300: Fill the system call table using a CALL() macro h8300: Fix <asm/tlb.h> h8300: Hardcode symbol prefixes in asm sources h8300: add missing definition for read_barries_depends() frv: head.S - Remove commented-out initialization code cris: Wire up asm-generic/vga.h parport: disable PC-style parallel port support on cris console: Disable VGA text console support on cris ...
2013-07-02Merge branch 'for-3.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull per-cpu changes from Tejun Heo: "This pull request contains Kent's per-cpu reference counter. It has gone through several iterations since the last time and the dynamic allocation is gone. The usual usage is relatively straight-forward although async kill confirm interface, which is not used int most cases, is somewhat icky. There also are some interface concerns - e.g. I'm not sure about passing in @relesae callback during init as that becomes funny when we later implement synchronous kill_and_drain - but nothing too serious and it's quite useable now. cgroup_subsys_state refcnting has already been converted and we should convert module refcnt (Kent?)" * 'for-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: percpu-refcount: use RCU-sched insted of normal RCU percpu-refcount: implement percpu_tryget() along with percpu_ref_kill_and_confirm() percpu-refcount: implement percpu_ref_cancel_init() percpu-refcount: add __must_check to percpu_ref_init() and don't use ACCESS_ONCE() in percpu_ref_kill_rcu() percpu-refcount: cosmetic updates percpu-refcount: consistently use plain (non-sched) RCU percpu-refcount: Don't use silly cmpxchg() percpu: implement generic percpu refcounting
2013-07-02Merge branch 'core-mutexes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull WW mutex support from Ingo Molnar: "This tree adds support for wound/wait style locks, which the graphics guys would like to make use of in the TTM graphics subsystem. Wound/wait mutexes are used when other multiple lock acquisitions of a similar type can be done in an arbitrary order. The deadlock handling used here is called wait/wound in the RDBMS literature: The older tasks waits until it can acquire the contended lock. The younger tasks needs to back off and drop all the locks it is currently holding, ie the younger task is wounded. See this LWN.net description of W/W mutexes: https://lwn.net/Articles/548909/ The comments there outline specific usecases for this facility (which have already been implemented for the DRM tree). Also see Documentation/ww-mutex-design.txt for more details" * 'core-mutexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking-selftests: Handle unexpected failures more strictly mutex: Add more w/w tests to test EDEADLK path handling mutex: Add more tests to lib/locking-selftest.c mutex: Add w/w tests to lib/locking-selftest.c mutex: Add w/w mutex slowpath debugging mutex: Add support for wound/wait style locks arch: Make __mutex_fastpath_lock_retval return whether fastpath succeeded or not
2013-07-02Merge tag 'fixes-non-critical-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC non-cricitical bug fixes from Arnd Bergmann: "These are various bug fixes that were not considered important enough for merging into 3.10. The majority of the ARM fixes are for the OMAP and at91 platforms, and there is another set of bug fixes for device drivers that resolve 'randconfig' build errors and that the subsystem maintainers either did not pick up or preferred to get merged through the arm-soc tree." * tag 'fixes-non-critical-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (43 commits) ARM: at91/PMC: use at91_usb_rate() for UTMI PLL ARM: at91/PMC: fix at91sam9n12 USB FS init ARM: at91/PMC: at91sam9n12 family has a PLLB ARM: at91/PMC: sama5d3 family doesn't have a PLLB ARM: tegra: fix section mismatch in tegra_pmc_parse_dt ARM: mxs: don't select HAVE_PWM ARM: mxs: stub out mxs_pm_init for !CONFIG_PM cpuidle: calxeda: select ARM_CPU_SUSPEND ARM: mvebu: fix length of ethernet registers in mv78260 dtsi ARM: at91: cpuidle: Fix target_residency ARM: at91: fix at91_extern_irq usage for non-dt boards ARM: sirf: use CONFIG_SIRF rather than CONFIG_PRIMA2 where necessary clocksource: kona: adapt to CLOCKSOURCE_OF_DECLARE change X.509: do not emit any informational output mtd: omap2: allow bulding as a module [SCSI] nsp32: use mdelay instead of large udelay constants hwrng: bcm2835: fix MODULE_LICENSE tag ARM: at91: Change the internal SRAM memory type MT_MEMORY_NONCACHED ARM: at91: Fix link breakage when !CONFIG_PHYLIB MAINTAINERS: Add exynos filename match to ARM/S5P EXYNOS ARM ARCHITECTURES ...
2013-07-02Merge tag 'driver-core-3.11-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here's the big driver core merge for 3.11-rc1 Lots of little things, and larger firmware subsystem updates, all described in the shortlog. Nice thing here is that we finally get rid of CONFIG_HOTPLUG, after 10+ years, thanks to Stephen Rohtwell (it had been always on for a number of kernel releases, now it's just removed)" * tag 'driver-core-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (27 commits) driver core: device.h: fix doc compilation warnings firmware loader: fix another compile warning with PM_SLEEP unset build some drivers only when compile-testing firmware loader: fix compile warning with PM_SLEEP set kobject: sanitize argument for format string sysfs_notify is only possible on file attributes firmware loader: simplify holding module for request_firmware firmware loader: don't export cache_firmware and uncache_firmware drivers/base: Use attribute groups to create sysfs memory files firmware loader: fix compile warning firmware loader: fix build failure with !CONFIG_FW_LOADER_USER_HELPER Documentation: Updated broken link in HOWTO Finally eradicate CONFIG_HOTPLUG driver core: firmware loader: kill FW_ACTION_NOHOTPLUG requests before suspend driver core: firmware loader: don't cache FW_ACTION_NOHOTPLUG firmware Documentation: Tidy up some drivers/base/core.c kerneldoc content. platform_device: use a macro instead of platform_driver_register firmware: move EXPORT_SYMBOL annotations firmware: Avoid deadlock of usermodehelper lock at shutdown dell_rbu: Select CONFIG_FW_LOADER_USER_HELPER explicitly ...
2013-06-28lib: Move fonts from drivers/video/console/ to lib/fonts/Geert Uytterhoeven
Several drivers need font support independent of CONFIG_VT, cfr. commit 9cbce8d7e1dae0744ca4f68d62aa7de18196b6f4, "console/font: Refactor font support code selection logic"). Hence move the fonts and their support logic from drivers/video/console/ to its own library directory lib/fonts/. This also allows to limit processing of drivers/video/console/Makefile to CONFIG_VT=y again. [Kevin Hilman <khilman@linaro.org>: Update arch/arm/boot/compressed/Makefile] Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-06-26locking-selftests: Handle unexpected failures more strictlyMaarten Lankhorst
When CONFIG_PROVE_LOCKING is not enabled, more tests are expected to pass unexpectedly, but there no tests that should start to fail that pass with CONFIG_PROVE_LOCKING enabled. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Cc: rostedt@goodmis.org Cc: daniel@ffwll.ch Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130620113151.4001.77963.stgit@patser Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26mutex: Add more w/w tests to test EDEADLK path handlingMaarten Lankhorst
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Cc: rostedt@goodmis.org Cc: daniel@ffwll.ch Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130620113141.4001.54331.stgit@patser Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26mutex: Add more tests to lib/locking-selftest.cMaarten Lankhorst
None of the ww_mutex codepaths should be taken in the 'normal' mutex calls. The easiest way to verify this is by using the normal mutex calls, and making sure o.ctx is unmodified. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Cc: robclark@gmail.com Cc: rostedt@goodmis.org Cc: daniel@ffwll.ch Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130620113130.4001.45423.stgit@patser Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26mutex: Add w/w tests to lib/locking-selftest.cMaarten Lankhorst
This stresses the lockdep code in some ways specifically useful to ww_mutexes. It adds checks for most of the common locking errors. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Cc: robclark@gmail.com Cc: rostedt@goodmis.org Cc: daniel@ffwll.ch Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130620113124.4001.23186.stgit@patser Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26mutex: Add w/w mutex slowpath debuggingDaniel Vetter
Injects EDEADLK conditions at pseudo-random interval, with exponential backoff up to UINT_MAX (to ensure that every lock operation still completes in a reasonable time). This way we can test the wound slowpath even for ww mutex users where contention is never expected, and the ww deadlock avoidance algorithm is only needed for correctness against malicious userspace. An example would be protecting kernel modesetting properties, which thanks to single-threaded X isn't really expected to contend, ever. I've looked into using the CONFIG_FAULT_INJECTION infrastructure, but decided against it for two reasons: - EDEADLK handling is mandatory for ww mutex users and should never affect the outcome of a syscall. This is in contrast to -ENOMEM injection. So fine configurability isn't required. - The fault injection framework only allows to set a simple probability for failure. Now the probability that a ww mutex acquire stage with N locks will never complete (due to too many injected EDEADLK backoffs) is zero. But the expected number of ww_mutex_lock operations for the completely uncontended case would be O(exp(N)). The per-acuiqire ctx exponential backoff solution choosen here only results in O(log N) overhead due to injection and so O(log N * N) lock operations. This way we can fail with high probability (and so have good test coverage even for fancy backoff and lock acquisition paths) without running into patalogical cases. Note that EDEADLK will only ever be injected when we managed to acquire the lock. This prevents any behaviour changes for users which rely on the EALREADY semantics. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Cc: rostedt@goodmis.org Cc: daniel@ffwll.ch Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130620113117.4001.21681.stgit@patser Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26mutex: Add support for wound/wait style locksMaarten Lankhorst
Wound/wait mutexes are used when other multiple lock acquisitions of a similar type can be done in an arbitrary order. The deadlock handling used here is called wait/wound in the RDBMS literature: The older tasks waits until it can acquire the contended lock. The younger tasks needs to back off and drop all the locks it is currently holding, i.e. the younger task is wounded. For full documentation please read Documentation/ww-mutex-design.txt. References: https://lwn.net/Articles/548909/ Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Acked-by: Rob Clark <robdclark@gmail.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Cc: rostedt@goodmis.org Cc: daniel@ffwll.ch Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/51C8038C.9000106@canonical.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19X.509: do not emit any informational outputArnd Bergmann
When building a kernel using 'make -s', I expect to see an empty output, except for build warnings and errors. The build_OID_registry code always prints one line when run, which is not helpful to most people building the kernels, and which makes it harder to automatically check for build warnings. Let's just remove the one line output. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: David Howells <dhowells@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au>
2013-06-18treewide: Fix typo in printkMasanari Iida
Correct spelling typo in printk within various drivers. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-06-17Merge 3.10-rc6 into driver-core-nextGreg Kroah-Hartman
We want these fixes here too. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17Merge 3.10-rc6 into char-misc-nextGreg Kroah-Hartman
We want the fixes in here.
2013-06-16percpu-refcount: use RCU-sched insted of normal RCUTejun Heo
percpu-refcount was incorrectly using preempt_disable/enable() for RCU critical sections against call_rcu(). 6a24474da8 ("percpu-refcount: consistently use plain (non-sched) RCU") fixed it by converting the preepmtion operations with rcu_read_[un]lock() citing that there isn't any advantage in using sched-RCU over using the usual one; however, rcu_read_[un]lock() for the preemptible RCU implementation - CONFIG_TREE_PREEMPT_RCU, chosen when CONFIG_PREEMPT - are slightly more expensive than preempt_disable/enable(). In a contrived microbench which repeats the followings, - percpu_ref_get() - copy 32 bytes of data into percpu buffer - percpu_put_get() - copy 32 bytes of data into percpu buffer rcu_read_[un]lock() used in percpu_ref_get/put() makes it go slower by about 15% when compared to using sched-RCU. As the RCU critical sections are extremely short, using sched-RCU shouldn't have any latency implications. Convert to RCU-sched. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Kent Overstreet <koverstreet@google.com> Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rusty Russell <rusty@rustcorp.com.au>
2013-06-13percpu-refcount: implement percpu_tryget() along with ↵Tejun Heo
percpu_ref_kill_and_confirm() Implement percpu_tryget() which stops giving out references once the percpu_ref is visible as killed. Because the refcnt is per-cpu, different CPUs will start to see a refcnt as killed at different points in time and tryget() may continue to succeed on subset of cpus for a while after percpu_ref_kill() returns. For use cases where it's necessary to know when all CPUs start to see the refcnt as dead, percpu_ref_kill_and_confirm() is added. The new function takes an extra argument @confirm_kill which is invoked when the refcnt is guaranteed to be viewed as killed on all CPUs. While this isn't the prettiest interface, it doesn't force synchronous wait and is much safer than requiring the caller to do its own call_rcu(). v2: Patch description rephrased to emphasize that tryget() may continue to succeed on some CPUs after kill() returns as suggested by Kent. v3: Function comment in percpu_ref_kill_and_confirm() updated warning people to not depend on the implied RCU grace period from the confirm callback as it's an implementation detail. Signed-off-by: Tejun Heo <tj@kernel.org> Slightly-Grumpily-Acked-by: Kent Overstreet <koverstreet@google.com>
2013-06-13percpu-refcount: implement percpu_ref_cancel_init()Tejun Heo
Normally, percpu_ref_init() initializes and percpu_ref_kill() initiates destruction which completes asynchronously. The asynchronous destruction can be problematic in init failure path where the caller wants to destroy half-constructed object - distinguishing half-constructed objects from the usual release method can be painful for complex objects. This patch implements percpu_ref_cancel_init() which synchronously destroys the percpu_ref without invoking release. To avoid unintentional misuses, the function requires the ref to have finished percpu_ref_init() but never used and triggers WARN otherwise. v2: Explain the weird name and usage restriction in the function comment. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Kent Overstreet <koverstreet@google.com>
2013-06-13percpu-refcount: add __must_check to percpu_ref_init() and don't use ↵Tejun Heo
ACCESS_ONCE() in percpu_ref_kill_rcu() Two small changes. * Unlike most init functions, percpu_ref_init() allocates memory and may fail. Let's mark it with __must_check in case the caller forgets. * percpu_ref_kill_rcu() is unnecessarily using ACCESS_ONCE() to dereference @ref->pcpu_count, which can be misleading. The pointer is guaranteed to be valid and visible and can't change underneath the function. Drop ACCESS_ONCE(). Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-12percpu-refcount: cosmetic updatesTejun Heo
* s/percpu_ref_release/percpu_ref_func_t/ as it's customary to have _t postfix for types and the type is gonna be used for a different type of callback too. * Add @ARG to function comments. * Drop unnecessary and unaligned indentation from percpu_ref_init() function comment. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Kent Overstreet <koverstreet@google.com>
2013-06-12lib/mpi/mpicoder.c: looping issue, need stop when equal to zero, found by ↵Chen Gang
'EXTRA_FLAGS=-W'. For 'while' looping, need stop when 'nbytes == 0', or will cause issue. ('nbytes' is size_t which is always bigger or equal than zero). The related warning: (with EXTRA_CFLAGS=-W) lib/mpi/mpicoder.c:40:2: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] Signed-off-by: Chen Gang <gang.chen@asianux.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-06-07kobject: sanitize argument for format stringKees Cook
Unlike kobject_set_name(), the kset_create_and_add() interface does not provide a way to use format strings, so make sure that the interface cannot be abused accidentally. It looks like all current callers use static strings, so there's no existing flaw. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-05net: core: move mac_pton() to lib/net_utils.cAndy Shevchenko
Since we have at least one user of this function outside of CONFIG_NET scope, we have to provide this function independently. The proposed solution is to move it under lib/net_utils.c with corresponding configuration variable and select wherever it is needed. Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reported-by: Arnd Bergmann <arnd@arndb.de> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03percpu-refcount: Don't use silly cmpxchg()Kent Overstreet
The cmpxchg() was just to ensure the debug check didn't race, which was a bit excessive. The caller is supposed to do the appropriate synchronization, which means percpu_ref_kill() can just do a simple store. Signed-off-by: Kent Overstreet <koverstreet@google.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-03percpu: implement generic percpu refcountingKent Overstreet
This implements a refcount with similar semantics to atomic_get()/atomic_dec_and_test() - but percpu. It also implements two stage shutdown, as we need it to tear down the percpu counts. Before dropping the initial refcount, you must call percpu_ref_kill(); this puts the refcount in "shutting down mode" and switches back to a single atomic refcount with the appropriate barriers (synchronize_rcu()). It's also legal to call percpu_ref_kill() multiple times - it only returns true once, so callers don't have to reimplement shutdown synchronization. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: coding-style tweak] Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Zach Brown <zab@redhat.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Cc: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-03debugfs: add get/set for atomic typesSeth Jennings
debugfs currently lack the ability to create attributes that set/get atomic_t values. This patch adds support for this through a new debugfs_create_atomic_t() function. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-29sprintf: hex_string(): fix commentSteven Rostedt
hex_string() had a typo in a comment. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-24MPILIB: disable usage of floating point registers on pariscHelge Deller
The umul_ppmm() macro for parisc uses the xmpyu assembler statement which does calculation via a floating point register. But usage of floating point registers inside the Linux kernel are not allowed and gcc will stop compilation due to the -mdisable-fpregs compiler option. Fix this by disabling the umul_ppmm() and udiv_qrnnd() macros. The mpilib will then use the generic built-in implementations instead. Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-23Merge tag 'driver-core-3.10-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core fixes from Greg Kroah-Hartman: "Here are 3 tiny driver core fixes for 3.10-rc2. A needed symbol export, a change to make it easier to track down offending sysfs files with incorrect attributes, and a klist bugfix. All have been in linux-next for a while" * tag 'driver-core-3.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: klist: del waiter from klist_remove_waiters before wakeup waitting process driver core: print sysfs attribute name when warning about bogus permissions driver core: export subsys_virtual_register
2013-05-23lib: make iovec obj instead of libRandy Dunlap
Fix build error io vmw_vmci.ko when CONFIG_VMWARE_VMCI=m by chaning iovec.o from lib-y to obj-y. ERROR: "memcpy_toiovec" [drivers/misc/vmw_vmci/vmw_vmci.ko] undefined! ERROR: "memcpy_fromiovec" [drivers/misc/vmw_vmci/vmw_vmci.ko] undefined! Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-21klist: del waiter from klist_remove_waiters before wakeup waitting processwang, biao
There is a race between klist_remove and klist_release. klist_remove uses a local var waiter saved on stack. When klist_release calls wake_up_process(waiter->process) to wake up the waiter, waiter might run immediately and reuse the stack. Then, klist_release calls list_del(&waiter->list) to change previous wait data and cause prior waiter thread corrupt. The patch fixes it against kernel 3.9. Signed-off-by: wang, biao <biao.wang@intel.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20Hoist memcpy_fromiovec/memcpy_toiovec into lib/Rusty Russell
ERROR: "memcpy_fromiovec" [drivers/vhost/vhost_scsi.ko] undefined! That function is only present with CONFIG_NET. Turns out that crypto/algif_skcipher.c also uses that outside net, but it actually needs sockets anyway. In addition, commit 6d4f0139d642c45411a47879325891ce2a7c164a added CONFIG_NET dependency to CONFIG_VMCI for memcpy_toiovec, so hoist that function and revert that commit too. socket.h already includes uio.h, so no callers need updating; trying only broke things fo x86_64 randconfig (thanks Fengguang!). Reported-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-05-08Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "It might look big in volume, but when categorized, not a lot of drivers are touched. The pull request contains: - mtip32xx fixes from Micron. - A slew of drbd updates, this time in a nicer series. - bcache, a flash/ssd caching framework from Kent. - Fixes for cciss" * 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits) bcache: Use bd_link_disk_holder() bcache: Allocator cleanup/fixes cciss: bug fix to prevent cciss from loading in kdump crash kernel cciss: add cciss_allow_hpsa module parameter drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions mtip32xx: Workaround for unaligned writes bcache: Make sure blocksize isn't smaller than device blocksize bcache: Fix merge_bvec_fn usage for when it modifies the bvm bcache: Correctly check against BIO_MAX_PAGES bcache: Hack around stuff that clones up to bi_max_vecs bcache: Set ra_pages based on backing device's ra_pages bcache: Take data offset from the bdev superblock. mtip32xx: mtip32xx: Disable TRIM support mtip32xx: fix a smatch warning bcache: Disable broken btree fuzz tester bcache: Fix a format string overflow bcache: Fix a minor memory leak on device teardown bcache: Documentation updates bcache: Use WARN_ONCE() instead of __WARN() bcache: Add missing #include <linux/prefetch.h> ...
2013-05-07rwsem: check counter to avoid cmpxchg callsDavidlohr Bueso
This patch tries to reduce the amount of cmpxchg calls in the writer failed path by checking the counter value first before issuing the instruction. If ->count is not set to RWSEM_WAITING_BIAS then there is no point wasting a cmpxchg call. Furthermore, Michel states "I suppose it helps due to the case where someone else steals the lock while we're trying to acquire sem->wait_lock." Two very different workloads and machines were used to see how this patch improves throughput: pgbench on a quad-core laptop and aim7 on a large 8 socket box with 80 cores. Some results comparing Michel's fast-path write lock stealing (tps-rwsem) on a quad-core laptop running pgbench: | db_size | clients | tps-rwsem | tps-patch | +---------+----------+----------------+--------------+ | 160 MB | 1 | 6906 | 9153 | + 32.5 | 160 MB | 2 | 15931 | 22487 | + 41.1% | 160 MB | 4 | 33021 | 32503 | | 160 MB | 8 | 34626 | 34695 | | 160 MB | 16 | 33098 | 34003 | | 160 MB | 20 | 31343 | 31440 | | 160 MB | 30 | 28961 | 28987 | | 160 MB | 40 | 26902 | 26970 | | 160 MB | 50 | 25760 | 25810 | ------------------------------------------------------ | 1.6 GB | 1 | 7729 | 7537 | | 1.6 GB | 2 | 19009 | 23508 | + 23.7% | 1.6 GB | 4 | 33185 | 32666 | | 1.6 GB | 8 | 34550 | 34318 | | 1.6 GB | 16 | 33079 | 32689 | | 1.6 GB | 20 | 31494 | 31702 | | 1.6 GB | 30 | 28535 | 28755 | | 1.6 GB | 40 | 27054 | 27017 | | 1.6 GB | 50 | 25591 | 25560 | ------------------------------------------------------ | 7.6 GB | 1 | 6224 | 7469 | + 20.0% | 7.6 GB | 2 | 13611 | 12778 | | 7.6 GB | 4 | 33108 | 32927 | | 7.6 GB | 8 | 34712 | 34878 | | 7.6 GB | 16 | 32895 | 33003 | | 7.6 GB | 20 | 31689 | 31974 | | 7.6 GB | 30 | 29003 | 28806 | | 7.6 GB | 40 | 26683 | 26976 | | 7.6 GB | 50 | 25925 | 25652 | ------------------------------------------------------ For the aim7 worloads, they overall improved on top of Michel's patchset. For full graphs on how the rwsem series plus this patch behaves on a large 8 socket machine against a vanilla kernel: http://stgolabs.net/rwsem-aim7-results.tar.gz Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07kref: minor cleanupAnatol Pomozov
- make warning smp-safe - result of atomic _unless_zero functions should be checked by caller to avoid use-after-free error - trivial whitespace fix. Link: https://lkml.org/lkml/2013/4/12/391 Tested: compile x86, boot machine and run xfstests Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> [ Removed line-break, changed to use WARN_ON_ONCE() - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07Merge branch 'rwsem-optimizations'Linus Torvalds
Merge rwsem optimizations from Michel Lespinasse: "These patches extend Alex Shi's work (which added write lock stealing on the rwsem slow path) in order to provide rwsem write lock stealing on the fast path (that is, without taking the rwsem's wait_lock). I have unfortunately been unable to push this through -next before due to Ingo Molnar / David Howells / Peter Zijlstra being busy with other things. However, this has gotten some attention from Rik van Riel and Davidlohr Bueso who both commented that they felt this was ready for v3.10, and Ingo Molnar has said that he was OK with me pushing directly to you. So, here goes :) Davidlohr got the following test results from pgbench running on a quad-core laptop: | db_size | clients | tps-vanilla | tps-rwsem | +---------+----------+----------------+--------------+ | 160 MB | 1 | 5803 | 6906 | + 19.0% | 160 MB | 2 | 13092 | 15931 | | 160 MB | 4 | 29412 | 33021 | | 160 MB | 8 | 32448 | 34626 | | 160 MB | 16 | 32758 | 33098 | | 160 MB | 20 | 26940 | 31343 | + 16.3% | 160 MB | 30 | 25147 | 28961 | | 160 MB | 40 | 25484 | 26902 | | 160 MB | 50 | 24528 | 25760 | ------------------------------------------------------ | 1.6 GB | 1 | 5733 | 7729 | + 34.8% | 1.6 GB | 2 | 9411 | 19009 | + 101.9% | 1.6 GB | 4 | 31818 | 33185 | | 1.6 GB | 8 | 33700 | 34550 | | 1.6 GB | 16 | 32751 | 33079 | | 1.6 GB | 20 | 30919 | 31494 | | 1.6 GB | 30 | 28540 | 28535 | | 1.6 GB | 40 | 26380 | 27054 | | 1.6 GB | 50 | 25241 | 25591 | ------------------------------------------------------ | 7.6 GB | 1 | 5779 | 6224 | | 7.6 GB | 2 | 10897 | 13611 | + 24.9% | 7.6 GB | 4 | 32683 | 33108 | | 7.6 GB | 8 | 33968 | 34712 | | 7.6 GB | 16 | 32287 | 32895 | | 7.6 GB | 20 | 27770 | 31689 | + 14.1% | 7.6 GB | 30 | 26739 | 29003 | | 7.6 GB | 40 | 24901 | 26683 | | 7.6 GB | 50 | 17115 | 25925 | + 51.5% ------------------------------------------------------ (Davidlohr also has one additional patch which further improves throughput, though I will ask him to send it directly to you as I have suggested some minor changes)." * emailed patches from Michel Lespinasse <walken@google.com>: rwsem: no need for explicit signed longs x86 rwsem: avoid taking slow path when stealing write lock rwsem: do not block readers at head of queue if other readers are active rwsem: implement support for write lock stealing on the fastpath rwsem: simplify __rwsem_do_wake rwsem: skip initial trylock in rwsem_down_write_failed rwsem: avoid taking wait_lock in rwsem_down_write_failed rwsem: use cmpxchg for trying to steal write lock rwsem: more agressive lock stealing in rwsem_down_write_failed rwsem: simplify rwsem_down_write_failed rwsem: simplify rwsem_down_read_failed rwsem: move rwsem_down_failed_common code into rwsem_down_{read,write}_failed rwsem: shorter spinlocked section in rwsem_down_failed_common() rwsem: make the waiter type an enumeration rather than a bitmask