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2015-06-22Merge branch 'perf-core-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Kernel side changes mostly consist of work on x86 PMU drivers: - x86 Intel PT (hardware CPU tracer) improvements (Alexander Shishkin) - x86 Intel CQM (cache quality monitoring) improvements (Thomas Gleixner) - x86 Intel PEBSv3 support (Peter Zijlstra) - x86 Intel PEBS interrupt batching support for lower overhead sampling (Zheng Yan, Kan Liang) - x86 PMU scheduler fixes and improvements (Peter Zijlstra) There's too many tooling improvements to list them all - here are a few select highlights: 'perf bench': - Introduce new 'perf bench futex' benchmark: 'wake-parallel', to measure parallel waker threads generating contention for kernel locks (hb->lock). (Davidlohr Bueso) 'perf top', 'perf report': - Allow disabling/enabling events dynamicaly in 'perf top': a 'perf top' session can instantly become a 'perf report' one, i.e. going from dynamic analysis to a static one, returning to a dynamic one is possible, to toogle the modes, just press 'f' to 'freeze/unfreeze' the sampling. (Arnaldo Carvalho de Melo) - Make Ctrl-C stop processing on TUI, allowing interrupting the load of big perf.data files (Namhyung Kim) 'perf probe': (Masami Hiramatsu) - Support glob wildcards for function name - Support $params special probe argument: Collect all function arguments - Make --line checks validate C-style function name. - Add --no-inlines option to avoid searching inline functions - Greatly speed up 'perf probe --list' by caching debuginfo. - Improve --filter support for 'perf probe', allowing using its arguments on other commands, as --add, --del, etc. 'perf sched': - Add option in 'perf sched' to merge like comms to lat output (Josef Bacik) Plus tons of infrastructure work - in particular preparation for upcoming threaded perf report support, but also lots of other work - and fixes and other improvements. See (much) more details in the shortlog and in the git log" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (305 commits) perf tools: Configurable per thread proc map processing time out perf tools: Add time out to force stop proc map processing perf report: Fix sort__sym_cmp to also compare end of symbol perf hists browser: React to unassigned hotkey pressing perf top: Tell the user how to unfreeze events after pressing 'f' perf hists browser: Honour the help line provided by builtin-{top,report}.c perf hists browser: Do not exit when 'f' is pressed in 'report' mode perf top: Replace CTRL+z with 'f' as hotkey for enable/disable events perf annotate: Rename source_line_percent to source_line_samples perf annotate: Display total number of samples with --show-total-period perf tools: Ensure thread-stack is flushed perf top: Allow disabling/enabling events dynamicly perf evlist: Add toggle_enable() method perf trace: Fix race condition at the end of started workloads perf probe: Speed up perf probe --list by caching debuginfo perf probe: Show usage even if the last event is skipped perf tools: Move libtraceevent dynamic list to separated LDFLAGS variable perf tools: Fix a problem when opening old perf.data with different byte order perf tools: Ignore .config-detected in .gitignore perf probe: Fix to return error if no probe is added ...
2015-05-27rcu: Remove prompt for RCU implementationPranith Kumar1-12/+6
The RCU implementation is chosen based on PREEMPT and SMP config options and is not really a user-selectable choice. This commit removes the menu entry, given that there is not much point in calling something a choice when there is in fact no choice.. The TINY_RCU, TREE_RCU, and PREEMPT_RCU Kconfig options continue to be selected based solely on the values of the PREEMPT and SMP options. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-05-27rcu: Make RCU able to tolerate undefined CONFIG_RCU_KTHREAD_PRIOPaul E. McKenney1-0/+1
This commit updates the initialization of the kthread_prio boot parameter so that RCU will build even when CONFIG_RCU_KTHREAD_PRIO is undefined. The kthread_prio boot parameter is set to CONFIG_RCU_KTHREAD_PRIO if that is defined, otherwise to 1 if CONFIG_RCU_BOOST is defined and to zero otherwise. This commit then makes CONFIG_RCU_KTHREAD_PRIO depend on CONFIG_RCU_EXPERT, so that Kconfig users won't be asked about CONFIG_RCU_KTHREAD_PRIO unless they want to be. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27rcu: Make RCU able to tolerate undefined CONFIG_RCU_FANOUT_LEAFPaul E. McKenney1-1/+1
This commit introduces an RCU_FANOUT_LEAF C-preprocessor macro so that RCU will build even when CONFIG_RCU_FANOUT_LEAF is undefined. The RCU_FANOUT_LEAF macro is set to the value of CONFIG_RCU_FANOUT_LEAF when defined, otherwise it is set to 32 for 32-bit systems and 64 for 64-bit systems. This commit then makes CONFIG_RCU_FANOUT_LEAF depend on CONFIG_RCU_EXPERT, so that Kconfig users won't be asked about CONFIG_RCU_FANOUT_LEAF unless they want to be. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27rcu: Make RCU able to tolerate undefined CONFIG_RCU_FANOUTPaul E. McKenney1-1/+1
This commit introduces an RCU_FANOUT C-preprocessor macro so that RCU will build even when CONFIG_RCU_FANOUT is undefined. The RCU_FANOUT macro is set to the value of CONFIG_RCU_FANOUT when defined, otherwise it is set to 32 for 32-bit systems and 64 for 64-bit systems. This commit then makes CONFIG_RCU_FANOUT depend on CONFIG_RCU_EXPERT, so that Kconfig users won't be asked about CONFIG_RCU_FANOUT unless they want to be. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27rcu: Break dependency of RCU_FANOUT_LEAF on RCU_FANOUTPaul E. McKenney1-2/+2
RCU_FANOUT_LEAF's range and default values depend on the value of RCU_FANOUT, which at the time seemed like a cute way to save two lines of Kconfig code. However, adding a dependency from both of these Kconfig parameters on RCU_EXPERT requires that RCU_FANOUT_LEAF operate correctly even if RCU_FANOUT is undefined. This commit therefore allows RCU_FANOUT_LEAF to take on the full range of permitted values, even in cases where RCU_FANOUT is undefined. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> [ paulmck: Eliminate redundant "default" as suggested by Pranith Kumar. ] Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27rcu: Create RCU_EXPERT Kconfig and hide booleans behind itPaul E. McKenney1-2/+17
This commit creates an RCU_EXPERT Kconfig and hides the independent boolean RCU-related user-visible Kconfig parameters behind it, namely RCU_FAST_NO_HZ and RCU_BOOST. This prevents Kconfig from asking about these parameters unless the user really wants to be asked. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27rcu: Convert CONFIG_RCU_FANOUT_EXACT to boot parameterPaul E. McKenney1-14/+0
The CONFIG_RCU_FANOUT_EXACT Kconfig parameter is used primarily (and perhaps only) by rcutorture to verify that RCU works correctly in specific rcu_node combining-tree configurations. It therefore does not make much sense have this as a question to people attempting to configure their kernels. So this commit creates an rcutree.rcu_fanout_exact= boot parameter that rcutorture can use, and eliminates the original CONFIG_RCU_FANOUT_EXACT Kconfig parameter. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27rcu: Directly drive RCU_USER_QS from KconfigPaul E. McKenney1-9/+1
Currently, Kconfig will ask the user whether RCU_USER_QS should be set. This is silly because Kconfig already has all the information that it needs to set this parameter. This commit therefore directly drives the value of RCU_USER_QS via NO_HZ_FULL's "select" statement. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
2015-05-27rcu: Directly drive TASKS_RCU from KconfigPaul E. McKenney1-3/+1
Currently, Kconfig will ask the user whether TASKS_RCU should be set. This is silly because Kconfig already has all the information that it needs to set this parameter. This commit therefore directly drives the value of TASKS_RCU via "select" statements. Which means that as subsystems require TASKS_RCU, those subsystems will need to add "select" statements of their own. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27Merge branch 'perf/urgent' into perf/core, before applying dependent patchesIngo Molnar1-2/+3
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08perf_event: Don't allow vmalloc() backed perf on powerpcMichael Ellerman1-1/+1
On powerpc the perf event interrupt is not masked when interrupts are disabled, allowing it to function as an NMI. This causes problems if perf is using vmalloc. If we take a page fault on the vmalloc region the fault handler will fail the page fault because it detects we are coming in from an NMI (see do_hash_page()). We don't actually need or want vmalloc backed perf so just disable it on powerpc. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <linuxppc-dev@ozlabs.org> Cc: Andrew Morton <akpm@osdl.org> Cc: Anton Blanchard <anton@samba.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@ghostprotocols.net Cc: sukadev@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1430720799-18426-1-git-send-email-mpe@ellerman.id.au Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-05init: fix regression by supporting devices with major:minor:offset formatChen Yu1-2/+3
Commit 283e7ad02 ("init: stricter checking of major:minor root= values") was so strict that it exposed the fact that a previously unknown device format was being used. Distributions like Ubuntu uses klibc (rather than uswsusp) to resume system from hibernation. klibc expressed the swap partition/file in the form of major:minor:offset. For example, 8:3:0 represents a swap partition in klibc, and klibc's resume process in initrd will finally echo 8:3:0 to /sys/power/resume for manually resuming. However, due to commit 283e7ad02's stricter checking, 8:3:0 will be treated as an invalid device format, and manual resuming from hibernation will fail. Fix this by adding support for devices with major:minor:offset format when resuming from hibernation. Reported-by: Prigent, Christophe <christophe.prigent@intel.com> Signed-off-by: Chen Yu <yu.c.chen@intel.com> Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-04-18Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6Linus Torvalds1-6/+0
Pull documentation updates from Jonathan Corbet: "Numerous fixes, the overdue removal of the i2o docs, some new Chinese translations, and, hopefully, the README fix that will end the flow of identical patches to that file" * tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (34 commits) Documentation/memcg: update memcg/kmem status Documentation: blackfin: Makefile: Typo building issue Documentation/vm/pagemap.txt: correct location of page-types tool Documentation/memory-barriers.txt: typo fix doc: Add guest_nice column to example output of `cat /proc/stat' Documentation/kernel-parameters: Move "eagerfpu" to its right place Documentation: gpio: Update ACPI part of the document to mention _DSD docs/completion.txt: Various tweaks and corrections doc: completion: context, scope and language fixes Documentation:Update Documentation/zh_CN/arm64/memory.txt Documentation:Update Documentation/zh_CN/arm64/booting.txt Documentation: Chinese translation of arm64/legacy_instructions.txt DocBook media: fix broken EIA hyperlink Documentation: tweak the maintainers entry README: Change gzip/bzip2 to xz compression format README: Update version number reference doc:pci: Fix typo in Documentation/PCI Documentation: drm: Use '->' when describing access through pointers. Documentation: Remove mentioning of block barriers Documentation/email-clients.txt: Fix one grammar mistake, add extra info about TB ...
2015-04-18Merge tag 'dm-4.1-changes' of ↵Linus Torvalds1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - the most extensive changes this cycle are the DM core improvements to add full blk-mq support to request-based DM. - disabled by default but user can opt-in with CONFIG_DM_MQ_DEFAULT - depends on some blk-mq changes from Jens' for-4.1/core branch so that explains why this pull is built on linux-block.git - update DM to use name_to_dev_t() rather than open-coding a less capable device parser. - includes a couple small improvements to name_to_dev_t() that offer stricter constraints that DM's code provided. - improvements to the dm-cache "mq" cache replacement policy. - a DM crypt crypt_ctr() error path fix and an async crypto deadlock fix - a small efficiency improvement for DM crypt decryption by leveraging immutable biovecs - add error handling modes for corrupted blocks to DM verity - a new "log-writes" DM target from Josef Bacik that is meant for file system developers to test file system integrity at particular points in the life of a file system - a few DM log userspace cleanups and fixes - a few Documentation fixes (for thin, cache, crypt and switch) * tag 'dm-4.1-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (34 commits) dm crypt: fix missing error code return from crypt_ctr error path dm crypt: fix deadlock when async crypto algorithm returns -EBUSY dm crypt: leverage immutable biovecs when decrypting on read dm crypt: update URLs to new cryptsetup project page dm: add log writes target dm table: use bool function return values of true/false not 1/0 dm verity: add error handling modes for corrupted blocks dm thin: remove stale 'trim' message documentation dm delay: use msecs_to_jiffies for time conversion dm log userspace base: fix compile warning dm log userspace transfer: match wait_for_completion_timeout return type dm table: fall back to getting device using name_to_dev_t() init: stricter checking of major:minor root= values init: export name_to_dev_t and mark name argument as const dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr dm: optimize dm_mq_queue_rq to _not_ use kthread if using pure blk-mq dm: add full blk-mq support to request-based DM dm: impose configurable deadline for dm_request_fn's merge heuristic dm sysfs: introduce ability to add writable attributes dm: don't start current request if it would've merged with the previous ...
2015-04-17kernel/fork.c: new function for max_threadsHeinrich Schuchardt1-2/+2
PAGE_SIZE is not guaranteed to be equal to or less than 8 times the THREAD_SIZE. E.g. architecture hexagon may have page size 1M and thread size 4096. This would lead to a division by zero in the calculation of max_threads. With this patch the buggy code is moved to a separate function set_max_threads. The error is not fixed. After fixing the problem in a separate patch the new function can be reused to adjust max_threads after adding or removing memory. Argument mempages of function fork_init() is removed as totalram_pages is an exported symbol. The creation of separate patches for refactoring to a new function and for fixing the logic was suggested by Ingo Molnar. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15kernel: conditionally support non-root users, groups and capabilitiesIulia Manda1-1/+18
There are a lot of embedded systems that run most or all of their functionality in init, running as root:root. For these systems, supporting multiple users is not necessary. This patch adds a new symbol, CONFIG_MULTIUSER, that makes support for non-root users, non-root groups, and capabilities optional. It is enabled under CONFIG_EXPERT menu. When this symbol is not defined, UID and GID are zero in any possible case and processes always have all capabilities. The following syscalls are compiled out: setuid, setregid, setgid, setreuid, setresuid, getresuid, setresgid, getresgid, setgroups, getgroups, setfsuid, setfsgid, capget, capset. Also, groups.c is compiled out completely. In kernel/capability.c, capable function was moved in order to avoid adding two ifdef blocks. This change saves about 25 KB on a defconfig build. The most minimal kernels have total text sizes in the high hundreds of kB rather than low MB. (The 25k goes down a bit with allnoconfig, but not that much. The kernel was booted in Qemu. All the common functionalities work. Adding users/groups is not possible, failing with -ENOSYS. Bloat-o-meter output: add/remove: 7/87 grow/shrink: 19/397 up/down: 1675/-26325 (-24650) [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Iulia Manda <iulia.manda21@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15init: stricter checking of major:minor root= valuesDan Ehrenberg1-1/+2
In the kernel command-line, previously, root=1:2jakshflaksjdhfa would be accepted and interpreted just like root=1:2. This patch adds stricter checking so that additional characters after major:minor are rejected by root=. The goal of this change is to help in unifying DM's interpretation of its block device argument by using existing kernel code (name_to_dev_t). But DM rejects malformed major:minor pairs, it seems reasonable for root= to reject them as well. Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-04-15init: export name_to_dev_t and mark name argument as constDan Ehrenberg1-1/+2
DM will switch its device lookup code to using name_to_dev_t() so it must be exported. Also, the @name argument should be marked const. Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-04-14Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-0/+2
Merge first patchbomb from Andrew Morton: - arch/sh updates - ocfs2 updates - kernel/watchdog feature - about half of mm/ * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits) Documentation: update arch list in the 'memtest' entry Kconfig: memtest: update number of test patterns up to 17 arm: add support for memtest arm64: add support for memtest memtest: use phys_addr_t for physical addresses mm: move memtest under mm mm, hugetlb: abort __get_user_pages if current has been oom killed mm, mempool: do not allow atomic resizing memcg: print cgroup information when system panics due to panic_on_oom mm: numa: remove migrate_ratelimited mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE mm: split ET_DYN ASLR from mmap ASLR s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE mm: expose arch_mmap_rnd when available s390: standardize mmap_rnd() usage powerpc: standardize mmap_rnd() usage mips: extract logic for mmap_rnd() arm64: standardize mmap_rnd() usage x86: standardize mmap_rnd() usage arm: factor out mmap ASLR into mmap_rnd ...
2015-04-14lib/ioremap.c: add huge I/O map capability interfacesToshi Kani1-0/+2
Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when I/O mappings with pud/pmd are enabled on the kernel. ioremap_huge_init() calls arch_ioremap_pud_supported() and arch_ioremap_pmd_supported() to initialize the capabilities at boot-time. A new kernel option "nohugeiomap" is also added, so that user can disable the huge I/O map capabilities when necessary. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Robert Elliott <Elliott@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14Merge branch 'perf-core-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf changes from Ingo Molnar: "Core kernel changes: - One of the more interesting features in this cycle is the ability to attach eBPF programs (user-defined, sandboxed bytecode executed by the kernel) to kprobes. This allows user-defined instrumentation on a live kernel image that can never crash, hang or interfere with the kernel negatively. (Right now it's limited to root-only, but in the future we might allow unprivileged use as well.) (Alexei Starovoitov) - Another non-trivial feature is per event clockid support: this allows, amongst other things, the selection of different clock sources for event timestamps traced via perf. This feature is sought by people who'd like to merge perf generated events with external events that were measured with different clocks: - cluster wide profiling - for system wide tracing with user-space events, - JIT profiling events etc. Matching perf tooling support is added as well, available via the -k, --clockid <clockid> parameter to perf record et al. (Peter Zijlstra) Hardware enablement kernel changes: - x86 Intel Processor Trace (PT) support: which is a hardware tracer on steroids, available on Broadwell CPUs. The hardware trace stream is directly output into the user-space ring-buffer, using the 'AUX' data format extension that was added to the perf core to support hardware constraints such as the necessity to have the tracing buffer physically contiguous. This patch-set was developed for two years and this is the result. A simple way to make use of this is to use BTS tracing, the PT driver emulates BTS output - available via the 'intel_bts' PMU. More explicit PT specific tooling support is in the works as well - will probably be ready by 4.2. (Alexander Shishkin, Peter Zijlstra) - x86 Intel Cache QoS Monitoring (CQM) support: this is a hardware feature of Intel Xeon CPUs that allows the measurement and allocation/partitioning of caches to individual workloads. These kernel changes expose the measurement side as a new PMU driver, which exposes various QoS related PMU events. (The partitioning change is work in progress and is planned to be merged as a cgroup extension.) (Matt Fleming, Peter Zijlstra; CPU feature detection by Peter P Waskiewicz Jr) - x86 Intel Haswell LBR call stack support: this is a new Haswell feature that allows the hardware recording of call chains, plus tooling support. To activate this feature you have to enable it via the new 'lbr' call-graph recording option: perf record --call-graph lbr perf report or: perf top --call-graph lbr This hardware feature is a lot faster than stack walk or dwarf based unwinding, but has some limitations: - It reuses the current LBR facility, so LBR call stack and branch record can not be enabled at the same time. - It is only available for user-space callchains. (Yan, Zheng) - x86 Intel Broadwell CPU support and various event constraints and event table fixes for earlier models. (Andi Kleen) - x86 Intel HT CPUs event scheduling workarounds. This is a complex CPU bug affecting the SNB,IVB,HSW families that results in counter value corruption. The mitigation code is automatically enabled and is transparent. (Maria Dimakopoulou, Stephane Eranian) The perf tooling side had a ton of changes in this cycle as well, so I'm only able to list the user visible changes here, in addition to the tooling changes outlined above: User visible changes affecting all tools: - Improve support of compressed kernel modules (Jiri Olsa) - Save DSO loading errno to better report errors (Arnaldo Carvalho de Melo) - Bash completion for subcommands (Yunlong Song) - Add 'I' event modifier for perf_event_attr.exclude_idle bit (Jiri Olsa) - Support missing -f to override perf.data file ownership. (Yunlong Song) - Show the first event with an invalid filter (David Ahern, Arnaldo Carvalho de Melo) User visible changes in individual tools: 'perf data': New tool for converting perf.data to other formats, initially for the CTF (Common Trace Format) from LTTng (Jiri Olsa, Sebastian Siewior) 'perf diff': Add --kallsyms option (David Ahern) 'perf list': Allow listing events with 'tracepoint' prefix (Yunlong Song) Sort the output of the command (Yunlong Song) 'perf kmem': Respect -i option (Jiri Olsa) Print big numbers using thousands' group (Namhyung Kim) Allow -v option (Namhyung Kim) Fix alignment of slab result table (Namhyung Kim) 'perf probe': Support multiple probes on different binaries on the same command line (Masami Hiramatsu) Support unnamed union/structure members data collection. (Masami Hiramatsu) Check kprobes blacklist when adding new events. (Masami Hiramatsu) 'perf record': Teach 'perf record' about perf_event_attr.clockid (Peter Zijlstra) Support recording running/enabled time (Andi Kleen) 'perf sched': Improve the performance of 'perf sched replay' on high CPU core count machines (Yunlong Song) 'perf report' and 'perf top': Allow annotating entries in callchains in the hists browser (Arnaldo Carvalho de Melo) Indicate which callchain entries are annotated in the TUI hists browser (Arnaldo Carvalho de Melo) Add pid/tid filtering to 'report' and 'script' commands (David Ahern) Consider PERF_RECORD_ events with cpumode == 0 in 'perf top', removing one cause of long term memory usage buildup, i.e. not processing PERF_RECORD_EXIT events (Arnaldo Carvalho de Melo) 'perf stat': Report unsupported events properly (Suzuki K. Poulose) Output running time and run/enabled ratio in CSV mode (Andi Kleen) 'perf trace': Handle legacy syscalls tracepoints (David Ahern, Arnaldo Carvalho de Melo) Only insert blank duration bracket when tracing syscalls (Arnaldo Carvalho de Melo) Filter out the trace pid when no threads are specified (Arnaldo Carvalho de Melo) Dump stack on segfaults (Arnaldo Carvalho de Melo) No need to explicitely enable evsels for workload started from perf, let it be enabled via perf_event_attr.enable_on_exec, removing some events that take place in the 'perf trace' before a workload is really started by it. (Arnaldo Carvalho de Melo) Allow mixing with tracepoints and suppressing plain syscalls. (Arnaldo Carvalho de Melo) There's also been a ton of infrastructure work done, such as the split-out of perf's build system into tools/build/ and other changes - see the shortlog and changelog for details" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (358 commits) perf/x86/intel/pt: Clean up the control flow in pt_pmu_hw_init() perf evlist: Fix type for references to data_head/tail perf probe: Check the orphaned -x option perf probe: Support multiple probes on different binaries perf buildid-list: Fix segfault when show DSOs with hits perf tools: Fix cross-endian analysis perf tools: Fix error path to do closedir() when synthesizing threads perf tools: Fix synthesizing fork_event.ppid for non-main thread perf tools: Add 'I' event modifier for exclude_idle bit perf report: Don't call map__kmap if map is NULL. perf tests: Fix attr tests perf probe: Fix ARM 32 building error perf tools: Merge all perf_event_attr print functions perf record: Add clockid parameter perf sched replay: Use replay_repeat to calculate the runavg of cpu usage instead of the default value 10 perf sched replay: Support using -f to override perf.data file ownership perf sched replay: Fix the EMFILE error caused by the limitation of the maximum open files perf sched replay: Handle the dead halt of sem_wait when create_tasks() fails for any task perf sched replay: Fix the segmentation fault problem caused by pr_err in threads perf sched replay: Realloc the memory of pid_to_task stepwise to adapt to the different pid_max configurations ...
2015-04-14Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds2-0/+14
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes from Ingo Molnar: "The main changes in this cycle were: - changes permitting use of call_rcu() and friends very early in boot, for example, before rcu_init() is invoked. - add in-kernel API to enable and disable expediting of normal RCU grace periods. - improve RCU's handling of (hotplug-) outgoing CPUs. - NO_HZ_FULL_SYSIDLE fixes. - tiny-RCU updates to make it more tiny. - documentation updates. - miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) cpu: Provide smpboot_thread_init() on !CONFIG_SMP kernels as well cpu: Defer smpboot kthread unparking until CPU known to scheduler rcu: Associate quiescent-state reports with grace period rcu: Yet another fix for preemption and CPU hotplug rcu: Add diagnostics to grace-period cleanup rcutorture: Default to grace-period-initialization delays rcu: Handle outgoing CPUs on exit from idle loop cpu: Make CPU-offline idle-loop transition point more precise rcu: Eliminate ->onoff_mutex from rcu_node structure rcu: Process offlining and onlining only at grace-period start rcu: Move rcu_report_unblock_qs_rnp() to common code rcu: Rework preemptible expedited bitmask handling rcu: Remove event tracing from rcu_cpu_notify(), used by offline CPUs rcutorture: Enable slow grace-period initializations rcu: Provide diagnostic option to slow down grace-period initialization rcu: Detect stalls caused by failure to propagate up rcu_node tree rcu: Eliminate empty HOTPLUG_CPU ifdef rcu: Simplify sync_rcu_preempt_exp_init() rcu: Put all orphan-callback-related code under same comment rcu: Consolidate offline-CPU callback initialization ...
2015-04-14Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree from Jiri Kosina: "Usual trivial tree updates. Nothing outstanding -- mostly printk() and comment fixes and unused identifier removals" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: goldfish: goldfish_tty_probe() is not using 'i' any more powerpc: Fix comment in smu.h qla2xxx: Fix printks in ql_log message lib: correct link to the original source for div64_u64 si2168, tda10071, m88ds3103: Fix firmware wording usb: storage: Fix printk in isd200_log_config() qla2xxx: Fix printk in qla25xx_setup_mode init/main: fix reset_device comment ipwireless: missing assignment goldfish: remove unreachable line of code coredump: Fix do_coredump() comment stacktrace.h: remove duplicate declaration task_struct smpboot.h: Remove unused function prototype treewide: Fix typo in printk messages treewide: Fix typo in printk messages mod_devicetable: fix comment for match_flags
2015-04-13cpu: Defer smpboot kthread unparking until CPU known to schedulerPaul E. McKenney1-0/+1
Currently, smpboot_unpark_threads() is invoked before the incoming CPU has been added to the scheduler's runqueue structures. This might potentially cause the unparked kthread to run on the wrong CPU, since the correct CPU isn't fully set up yet. That causes a sporadic, hard to debug boot crash triggering on some systems, reported by Borislav Petkov, and bisected down to: 2a442c9c6453 ("x86: Use common outgoing-CPU-notification code") This patch places smpboot_unpark_threads() in a CPU hotplug notifier with priority set so that these kthreads are unparked just after the CPU has been added to the runqueues. Reported-and-tested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-11Documentation/memcg: update memcg/kmem statusVladimir Davydov1-6/+0
Memcg/kmem reclaim support has been finally merged. Reflect this in the documentation. Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-04-02bpf: Fix the build on BPF_SYSCALL=y && !CONFIG_TRACING kernels, make it more ↵Ingo Molnar1-1/+1
configurable So bpf_tracing.o depends on CONFIG_BPF_SYSCALL - but that's not its only dependency, it also depends on the tracing infrastructure and on kprobes, without which it will fail to build with: In file included from kernel/trace/bpf_trace.c:14:0: kernel/trace/trace.h: In function ‘trace_test_and_set_recursion’: kernel/trace/trace.h:491:28: error: ‘struct task_struct’ has no member named ‘trace_recursion’ unsigned int val = current->trace_recursion; [...] It took quite some time to trigger this build failure, because right now BPF_SYSCALL is very obscure, depends on CONFIG_EXPERT. So also make BPF_SYSCALL more configurable, not just under CONFIG_EXPERT. If BPF_SYSCALL, tracing and kprobes are enabled then enable the bpf_tracing gateway as well. We might want to make this an interactive option later on, although I'd not complicate it unnecessarily: enabling BPF_SYSCALL is enough of an indicator that the user wants BPF support. Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-06init/main: fix reset_device commentFrans Klaver1-1/+1
Fix incorrect spelling of situation. Signed-off-by: Frans Klaver <fransklaver@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-03-05cpuset: initialize cpuset a bit earlyZefan Li1-1/+1
Now we call ss->bind() in cgroup_init(), so cgroup_init() will call cpuset_bind() and then the latter will access top_cpuset's cpumask, which is NULL, because cpuset_init() is called after cgroup_init() The simplest fix is to swap cgroup_init() and cpuset_init(). Cc: Vladimir Davydov <vdavydov@parallels.com> Fixes: 295458e67284 ("cgroup: call cgroup_subsys->bind on cgroup subsys initialization") Reported by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Vladimir Davydov <vdavydov@parallels.com>
2015-02-26rcu: Add Kconfig option to expedite grace periods during bootPaul E. McKenney1-0/+13
This commit adds a CONFIG_RCU_EXPEDITE_BOOT Kconfig parameter that emulates a very early boot rcu_expedite_gp(). A late-boot call to rcu_end_inkernel_boot() will provide the corresponding rcu_unexpedite_gp(). The late-boot call to rcu_end_inkernel_boot() should be made just before init is spawned. According to Arjan: > To show the boot time, I'm using the timestamp of the "Write protecting" > line, that's pretty much the last thing we print prior to ring 3 execution. > > A kernel with default RCU behavior (inside KVM, only virtual devices) > looks like this: > > [ 0.038724] Write protecting the kernel read-only data: 10240k > > a kernel with expedited RCU (using the command line option, so that I > don't have to recompile between measurements and thus am completely > oranges-to-oranges) > > [ 0.031768] Write protecting the kernel read-only data: 10240k > > which, in percentage, is an 18% improvement. Reported-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Arjan van de Ven <arjan@linux.intel.com>
2015-02-19Merge branch 'kconfig' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kconfig updates from Michal Marek: "Yann E Morin was supposed to take over kconfig maintainership, but this hasn't happened. So I'm sending a few kconfig patches that I collected: - Fix for missing va_end in kconfig - merge_config.sh displays used if given too few arguments - s/boolean/bool/ in Kconfig files for consistency, with the plan to only support bool in the future" * 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: kconfig: use va_end to match corresponding va_start merge_config.sh: Display usage if given too few arguments kconfig: use bool instead of boolean for type definition attributes
2015-02-19Merge branch 'misc' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull misc kbuild changes from Michal Marek: "Just a few non-critical kbuild changes: - builddeb adds the actual distribution name in the changelog - documentation fixes" * 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: kbuild: trivial - fix the help doc of CONFIG_CC_OPTIMIZE_FOR_SIZE kbuild: Update documentation of clean-files and clean-dirs builddeb: Try to determine distribution builddeb: Update year and git repository URL in debian/copyright
2015-02-13init: remove CONFIG_INIT_FALLBACKAndy Lutomirski2-21/+0
CONFIG_INIT_FALLBACK adds config bloat without an obvious use case that makes it worth keeping around. Delete it. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Frank Rowand <frowand.list@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Rob Landley <rob@landley.net> Cc: Shuah Khan <shuah.kh@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-09Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds1-13/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 APIC updates from Ingo Molnar: "Continued fallout of the conversion of the x86 IRQ code to the hierarchical irqdomain framework: more cleanups, simplifications, memory allocation behavior enhancements, mainly in the interrupt remapping and APIC code" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) x86, init: Fix UP boot regression on x86_64 iommu/amd: Fix irq remapping detection logic x86/acpi: Make acpi_[un]register_gsi_ioapic() depend on CONFIG_X86_LOCAL_APIC x86: Consolidate boot cpu timer setup x86/apic: Reuse apic_bsp_setup() for UP APIC setup x86/smpboot: Sanitize uniprocessor init x86/smpboot: Move apic init code to apic.c init: Get rid of x86isms x86/apic: Move apic_init_uniprocessor code x86/smpboot: Cleanup ioapic handling x86/apic: Sanitize ioapic handling x86/ioapic: Add proper checks to setp/enable_IO_APIC() x86/ioapic: Provide stub functions for IOAPIC%3Dn x86/smpboot: Move smpboot inlines to code x86/x2apic: Use state information for disable x86/x2apic: Split enable and setup function x86/x2apic: Disable x2apic from nox2apic setup x86/x2apic: Add proper state tracking x86/x2apic: Clarify remapping mode for x2apic enablement x86/x2apic: Move code in conditional region ...
2015-01-22init: Get rid of x86ismsThomas Gleixner1-13/+0
The UP local API support can be set up from an early initcall. No need for horrible hackery in the init code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211703.827943883@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-15Merge branches 'doc.2015.01.07a', 'fixes.2015.01.15a', ↵Paul E. McKenney1-5/+13
'preempt.2015.01.06a', 'srcu.2015.01.06a', 'stall.2015.01.16a' and 'torture.2015.01.11a' into HEAD doc.2015.01.07a: Documentation updates. fixes.2015.01.15a: Miscellaneous fixes. preempt.2015.01.06a: Changes to handling of lists of preempted tasks. srcu.2015.01.06a: SRCU updates. stall.2015.01.16a: RCU CPU stall-warning updates and fixes. torture.2015.01.11a: RCU torture-test updates and fixes.
2015-01-15rcu: Optionally run grace-period kthreads at real-time priorityPaul E. McKenney1-3/+4
Recent testing has shown that under heavy load, running RCU's grace-period kthreads at real-time priority can improve performance (according to 0day test robot) and reduce the incidence of RCU CPU stall warnings. However, most systems do just fine with the default non-realtime priorities for these kthreads, and it does not make sense to expose the entire user base to any risk stemming from this change, given that this change is of use only to a few users running extremely heavy workloads. Therefore, this commit allows users to specify realtime priorities for the grace-period kthreads, but leaves them running SCHED_OTHER by default. The realtime priority may be specified at build time via the RCU_KTHREAD_PRIO Kconfig parameter, or at boot time via the rcutree.kthread_prio parameter. Either way, 0 says to continue the default SCHED_OTHER behavior and values from 1-99 specify that priority of SCHED_FIFO behavior. Note that a value of 0 is not permitted when the RCU_BOOST Kconfig parameter is specified. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-01-08kbuild: trivial - fix the help doc of CONFIG_CC_OPTIMIZE_FOR_SIZEMasahiro Yamada1-2/+2
Other than GCC, we have another choice, Clang for building the kernel these days. It seems better to say "compiler" rather than "gcc". Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-01-07kconfig: use bool instead of boolean for type definition attributesChristoph Jaeger1-2/+2
Support for keyword 'boolean' will be dropped later on. No functional change. Reference: http://lkml.kernel.org/r/cover.1418003065.git.cj@linux.com Signed-off-by: Christoph Jaeger <cj@linux.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-01-06rcu: Make SRCU optional by using CONFIG_SRCUPranith Kumar1-0/+9
SRCU is not necessary to be compiled by default in all cases. For tinification efforts not compiling SRCU unless necessary is desirable. The current patch tries to make compiling SRCU optional by introducing a new Kconfig option CONFIG_SRCU which is selected when any of the components making use of SRCU are selected. If we do not select CONFIG_SRCU, srcu.o will not be compiled at all. text data bss dec hex filename 2007 0 0 2007 7d7 kernel/rcu/srcu.o Size of arch/powerpc/boot/zImage changes from text data bss dec hex filename 831552 64180 23944 919676 e087c arch/powerpc/boot/zImage : before 829504 64180 23952 917636 e0084 arch/powerpc/boot/zImage : after so the savings are about ~2000 bytes. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com> CC: Josh Triplett <josh@joshtriplett.org> CC: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> [ paulmck: resolve conflict due to removal of arch/ia64/kvm/Kconfig. ]
2015-01-06rcu: Remove "select IRQ_WORK" from config TREE_RCULai Jiangshan1-2/+0
The 48a7639ce80c ("rcu: Make callers awaken grace-period kthread") removed the irq_work_queue(), so the TREE_RCU doesn't need irq work any more. This commit therefore updates RCU's Kconfig and Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-12-17init: fix read-write root mountMiklos Szeredi1-2/+4
If mount flags don't have MS_RDONLY, iso9660 returns EACCES without actually checking if it's an iso image. This tricks mount_block_root() into retrying with MS_RDONLY. This results in a read-only root despite the "rw" boot parameter if the actual filesystem was checked after iso9660. I believe the behavior of iso9660 is okay, while that of mount_block_root() is not. It should rather try all types without MS_RDONLY and only then retry with MS_RDONLY. This change also makes the code more robust against the case when EACCES is returned despite MS_RDONLY, which would've resulted in a lockup. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-16Merge branch 'for-linus' of ↵Linus Torvalds2-1/+6
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile #2 from Al Viro: "Next pile (and there'll be one or two more). The large piece in this one is getting rid of /proc/*/ns/* weirdness; among other things, it allows to (finally) make nameidata completely opaque outside of fs/namei.c, making for easier further cleanups in there" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: coda_venus_readdir(): use file_inode() fs/namei.c: fold link_path_walk() call into path_init() path_init(): don't bother with LOOKUP_PARENT in argument fs/namei.c: new helper (path_cleanup()) path_init(): store the "base" pointer to file in nameidata itself make default ->i_fop have ->open() fail with ENXIO make nameidata completely opaque outside of fs/namei.c kill proc_ns completely take the targets of /proc/*/ns/* symlinks to separate fs bury struct proc_ns in fs/proc copy address of proc_ns_ops into ns_common new helpers: ns_alloc_inum/ns_free_inum make proc_ns_operations work with struct ns_common * instead of void * switch the rest of proc_ns_operations to working with &...->ns netns: switch ->get()/->put()/->install()/->inum() to working with &net->ns make mntns ->get()/->put()/->install()/->inum() work with &mnt_ns->ns common object embedded into various struct ....ns
2014-12-16Merge tag 'trace-3.19-2' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "As the merge window is still open, and this code was not as complex as I thought it might be. I'm pushing this in now. This will allow Thomas to debug his irq work for 3.20. This adds two new features: 1) Allow traceopoints to be enabled right after mm_init(). By passing in the trace_event= kernel command line parameter, tracepoints can be enabled at boot up. For debugging things like the initialization of interrupts, it is needed to have tracepoints enabled very early. People have asked about this before and this has been on my todo list. As it can be helpful for Thomas to debug his upcoming 3.20 IRQ work, I'm pushing this now. This way he can add tracepoints into the IRQ set up and have users enable them when things go wrong. 2) Have the tracepoints printed via printk() (the console) when they are triggered. If the irq code locks up or reboots the box, having the tracepoint output go into the kernel ring buffer is useless for debugging. But being able to add the tp_printk kernel command line option along with the trace_event= option will have these tracepoints printed as they occur, and that can be really useful for debugging early lock up or reboot problems. This code is not that intrusive and it passed all my tests. Thomas tried them out too and it works for his needs. Link: http://lkml.kernel.org/r/20141214201609.126831471@goodmis.org" * tag 'trace-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Add tp_printk cmdline to have tracepoints go to printk() tracing: Move enabling tracepoints to just after rcu_init()
2014-12-15tracing: Move enabling tracepoints to just after rcu_init()Steven Rostedt (Red Hat)1-0/+4
Enabling tracepoints at boot up can be very useful. The tracepoint can be initialized right after RCU has been. There's no need to wait for the early_initcall() to be called. That's too late for some things that can use tracepoints for debugging. Move the logic to enable tracepoints out of the initcalls and into init/main.c to right after rcu_init(). This also allows trace_printk() to be used early too. Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1412121539300.16494@nanos Link: http://lkml.kernel.org/r/20141214164104.307127356@goodmis.org Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-12-14Merge branch 'next' of ↵Linus Torvalds1-1/+5
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security layer updates from James Morris: "In terms of changes, there's general maintenance to the Smack, SELinux, and integrity code. The IMA code adds a new kconfig option, IMA_APPRAISE_SIGNED_INIT, which allows IMA appraisal to require signatures. Support for reading keys from rootfs before init is call is also added" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (23 commits) selinux: Remove security_ops extern security: smack: fix out-of-bounds access in smk_parse_smack() VFS: refactor vfs_read() ima: require signature based appraisal integrity: provide a hook to load keys when rootfs is ready ima: load x509 certificate from the kernel integrity: provide a function to load x509 certificate from the kernel integrity: define a new function integrity_read_file() Security: smack: replace kzalloc with kmem_cache for inode_smack Smack: Lock mode for the floor and hat labels ima: added support for new kernel cmdline parameter ima_template_fmt ima: allocate field pointers array on demand in template_desc_init_fields() ima: don't allocate a copy of template_fmt in template_desc_init_fields() ima: display template format in meas. list if template name length is zero ima: added error messages to template-related functions ima: use atomic bit operations to protect policy update interface ima: ignore empty and with whitespaces policy lines ima: no need to allocate entry for comment ima: report policy load status ima: use path names cache ...
2014-12-13mm/page_ext: resurrect struct page extending code for debuggingJoonsoo Kim1-0/+7
When we debug something, we'd like to insert some information to every page. For this purpose, we sometimes modify struct page itself. But, this has drawbacks. First, it requires re-compile. This makes us hesitate to use the powerful debug feature so development process is slowed down. And, second, sometimes it is impossible to rebuild the kernel due to third party module dependency. At third, system behaviour would be largely different after re-compile, because it changes size of struct page greatly and this structure is accessed by every part of kernel. Keeping this as it is would be better to reproduce errornous situation. This feature is intended to overcome above mentioned problems. This feature allocates memory for extended data per page in certain place rather than the struct page itself. This memory can be accessed by the accessor functions provided by this code. During the boot process, it checks whether allocation of huge chunk of memory is needed or not. If not, it avoids allocating memory at all. With this advantage, we can include this feature into the kernel in default and can avoid rebuild and solve related problems. Until now, memcg uses this technique. But, now, memcg decides to embed their variable to struct page itself and it's code to extend struct page has been removed. I'd like to use this code to develop debug feature, so this patch resurrect it. To help these things to work well, this patch introduces two callbacks for clients. One is the need callback which is mandatory if user wants to avoid useless memory allocation at boot-time. The other is optional, init callback, which is used to do proper initialization after memory is allocated. Detailed explanation about purpose of these functions is in code comment. Please refer it. Others are completely same with previous extension code in memcg. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10Merge branch 'nsfs' into for-nextAl Viro2-1/+6
2014-12-10take the targets of /proc/*/ns/* symlinks to separate fsAl Viro1-0/+2
New pseudo-filesystem: nsfs. Targets of /proc/*/ns/* live there now. It's not mountable (not even registered, so it's not in /proc/filesystems, etc.). Files on it *are* bindable - we explicitly permit that in do_loopback(). This stuff lives in fs/nsfs.c now; proc_ns_fget() moved there as well. get_proc_ns() is a macro now (it's simply returning ->i_private; would have been an inline, if not for header ordering headache). proc_ns_inode() is an ex-parrot. The interface used in procfs is ns_get_path(path, task, ops) and ns_get_name(buf, size, task, ops). Dentries and inodes are never hashed; a non-counting reference to dentry is stashed in ns_common (removed by ->d_prune()) and reused by ns_get_path() if present. See ns_get_path()/ns_prune_dentry/nsfs_evict() for details of that mechanism. As the result, proc_ns_follow_link() has stopped poking in nd->path.mnt; it does nd_jump_link() on a consistent <vfsmount,dentry> pair it gets from ns_get_path(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-10init: allow CONFIG_INIT_FALLBACK=n to disable defaults if init= failsAndy Lutomirski2-1/+22
If a user puts init=/whatever on the command line and /whatever can't be run, then the kernel will try a few default options before giving up. If init=/whatever came from a bootloader prompt, then this is unexpected but probably harmless. On the other hand, if it comes from a script (e.g. a tool like virtme or perhaps a future kselftest script), then the fallbacks are likely to exist, but they'll do the wrong thing. For example, they might unexpectedly invoke systemd. This adds a config option CONFIG_INIT_FALLBACK. If unset, then a failure to run the specified init= process be fatal. The tentative plan is to remove CONFIG_INIT_FALLBACK for 3.20. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Rob Landley <rob@landley.net> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Shuah Khan <shuah.kh@samsung.com> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>