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* Merge tag 'trace-v3.20' of ↵Linus Torvalds2015-02-1219-150/+175
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "The updates included in this pull request for ftrace are: o Several clean ups to the code One such clean up was to convert to 64 bit time keeping, in the ring buffer benchmark code. o Adding of __print_array() helper macro for TRACE_EVENT() o Updating the sample/trace_events/ to add samples of different ways to make trace events. Lots of features have been added since the sample code was made, and these features are mostly unknown. Developers have been making their own hacks to do things that are already available. o Performance improvements. Most notably, I found a performance bug where a waiter that is waiting for a full page from the ring buffer will see that a full page is not available, and go to sleep. The sched event caused by it going to sleep would cause it to wake up again. It would see that there was still not a full page, and go back to sleep again, and that would wake it up again, until finally it would see a full page. This change has been marked for stable. Other improvements include removing global locks from fast paths" * tag 'trace-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ring-buffer: Do not wake up a splice waiter when page is not full tracing: Fix unmapping loop in tracing_mark_write tracing: Add samples of DECLARE_EVENT_CLASS() and DEFINE_EVENT() tracing: Add TRACE_EVENT_FN example tracing: Add TRACE_EVENT_CONDITION sample tracing: Update the TRACE_EVENT fields available in the sample code tracing: Separate out initializing top level dir from instances tracing: Make tracing_init_dentry_tr() static trace: Use 64-bit timekeeping tracing: Add array printing helper tracing: Remove newline from trace_printk warning banner tracing: Use IS_ERR() check for return value of tracing_init_dentry() tracing: Remove unneeded includes of debugfs.h and fs.h tracing: Remove taking of trace_types_lock in pipe files tracing: Add ref count to tracer for when they are being read by pipe
| * ring-buffer: Do not wake up a splice waiter when page is not fullSteven Rostedt (Red Hat)2015-02-111-5/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an application connects to the ring buffer via splice, it can only read full pages. Splice does not work with partial pages. If there is not enough data to fill a page, the splice command will either block or return -EAGAIN (if set to nonblock). Code was added where if the page is not full, to just sleep again. The problem is, it will get woken up again on the next event. That is, when something is written into the ring buffer, if there is a waiter it will wake it up. The waiter would then check the buffer, see that it still does not have enough data to fill a page and go back to sleep. To make matters worse, when the waiter goes back to sleep, it could cause another event, which would wake it back up again to see it doesn't have enough data and sleep again. This produces a tremendous overhead and fills the ring buffer with noise. For example, recording sched_switch on an idle system for 10 seconds produces 25,350,475 events!!! Create another wait queue for those waiters wanting full pages. When an event is written, it only wakes up waiters if there's a full page of data. It does not wake up the waiter if the page is not yet full. After this change, recording sched_switch on an idle system for 10 seconds produces only 800 events. Getting rid of 25,349,675 useless events (99.9969% of events!!), is something to take seriously. Cc: stable@vger.kernel.org # 3.16+ Cc: Rabin Vincent <rabin@rab.in> Fixes: e30f53aad220 "tracing: Do not busy wait in buffer splice" Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Fix unmapping loop in tracing_mark_writeVikram Mulukutla2015-02-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 6edb2a8a385f0cdef51dae37ff23e74d76d8a6ce introduced an array map_pages that contains the addresses returned by kmap_atomic. However, when unmapping those pages, map_pages[0] is unmapped before map_pages[1], breaking the nesting requirement as specified in the documentation for kmap_atomic/kunmap_atomic. This was caught by the highmem debug code present in kunmap_atomic. Fix the loop to do the unmapping properly. Link: http://lkml.kernel.org/r/1418871056-6614-1-git-send-email-markivx@codeaurora.org Cc: stable@vger.kernel.org # 3.5+ Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Reported-by: Lime Yang <limey@codeaurora.org> Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Separate out initializing top level dir from instancesSteven Rostedt (Red Hat)2015-02-021-21/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The top level trace array is treated a little different than the instances, as it has to deal with more of the general tracing. The tr->dir is the tracing directory, which is an immutable dentry, where as the tr->dir of instances are the dentry that was created, and can be destroyed later. These should have different functions accessing them. As only tracing_init_dentry() deals with the top level array, fold the code for it into that function, and remove the trace_init_dentry_tr() that was also used by the instances to get their directory dentry. Add a tracing_get_dentry() to just get the tracing dir entry for instances as well as the top level array. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Make tracing_init_dentry_tr() staticSteven Rostedt (Red Hat)2015-02-022-2/+1
| | | | | | | | | | | | | | tracing_init_dentry_tr() is not used outside of trace.c, it should be static. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * trace: Use 64-bit timekeepingTina Ruchandani2015-01-281-10/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ring_buffer_producer uses 'struct timeval' to measure its start and end times. 'struct timeval' on 32-bit systems will have its tv_sec value overflow in year 2038 and beyond. This patch replaces struct timeval with 'ktime_t' which uses 64-bit representation for nanoseconds. Link: http://lkml.kernel.org/r/20150128141611.GA2701@tinar Suggested-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Add array printing helperDave Martin2015-01-281-0/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a trace event contains an array, there is currently no standard way to format this for text output. Drivers are currently hacking around this by a) local hacks that use the trace_seq functionailty directly, or b) just not printing that information. For fixed size arrays, formatting of the elements can be open-coded, but this gets cumbersome for arrays of non-trivial size. These approaches result in non-standard content of the event format description delivered to userspace, so userland tools needs to be taught to understand and parse each array printing method individually. This patch implements a __print_array() helper that tracepoint implementations can use instead of reinventing it. A simple C-style syntax is used to delimit the array and its elements {like,this}. So that the helpers can be used with large static arrays as well as dynamic arrays, they take a pointer and element count: they can be used with __get_dynamic_array() for use with dynamic arrays. Link: http://lkml.kernel.org/r/1422449335-8289-2-git-send-email-javi.merino@arm.com Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Javi Merino <javi.merino@arm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Remove newline from trace_printk warning bannerBorislav Petkov2015-01-271-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the output-confusing newline below: [ 0.191328] ********************************************************** [ 0.191493] ** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ** [ 0.191586] ** ** ... Link: http://lkml.kernel.org/r/1422375440-31970-1-git-send-email-bp@alien8.de Signed-off-by: Borislav Petkov <bp@suse.de> [ added an extra '\n' by itself, to keep what it was suppose to do ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Use IS_ERR() check for return value of tracing_init_dentry()Steven Rostedt (Red Hat)2015-01-229-12/+12
| | | | | | | | | | | | | | | | | | tracing_init_dentry() will soon return NULL as a valid pointer for the top level tracing directroy. NULL can not be used as an error value. Instead, switch to ERR_PTR() and check the return status with IS_ERR(). Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Remove unneeded includes of debugfs.h and fs.hSteven Rostedt (Red Hat)2015-01-229-17/+0
| | | | | | | | | | | | | | | | | | | | The creation of tracing files and directories is for the most part encapsulated in helper functions in trace.c. Other files do not need to include debugfs.h or fs.h, as they may have needed to in the past. Remove them from the files that do not need them. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Remove taking of trace_types_lock in pipe filesSteven Rostedt (Red Hat)2014-12-231-82/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Taking the global mutex "trace_types_lock" in the trace_pipe files causes a bottle neck as most the pipe files can be read per cpu and there's no reason to serialize them. The current_trace variable was given a ref count and it can not change when the ref count is not zero. Opening the trace_pipe files will up the ref count (and decremented on close), so that the lock no longer needs to be taken when accessing the current_trace variable. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Add ref count to tracer for when they are being read by pipeSteven Rostedt (Red Hat)2014-12-222-1/+16
| | | | | | | | | | | | | | | | | | | | | | | | When one of the trace pipe files are being read (by either the trace_pipe or trace_pipe_raw), do not allow the current_trace to change. By adding a ref count that is incremented when the pipe files are opened, will prevent the current_trace from being changed. This will allow for the removal of the global trace_types_lock from reading the pipe buffers (which is currently a bottle neck). Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2015-02-121-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: - The remaining patches for the z13 machine support: kernel build option for z13, the cache synonym avoidance, SMT support, compare-and-delay for spinloops and the CES5S crypto adapater. - The ftrace support for function tracing with the gcc hotpatch option. This touches common code Makefiles, Steven is ok with the changes. - The hypfs file system gets an extension to access diagnose 0x0c data in user space for performance analysis for Linux running under z/VM. - The iucv hvc console gets wildcard spport for the user id filtering. - The cacheinfo code is converted to use the generic infrastructure. - Cleanup and bug fixes. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits) s390/process: free vx save area when releasing tasks s390/hypfs: Eliminate hypfs interval s390/hypfs: Add diagnose 0c support s390/cacheinfo: don't use smp_processor_id() in preemptible context s390/zcrypt: fixed domain scanning problem (again) s390/smp: increase maximum value of NR_CPUS to 512 s390/jump label: use different nop instruction s390/jump label: add sanity checks s390/mm: correct missing space when reporting user process faults s390/dasd: cleanup profiling s390/dasd: add locking for global_profile access s390/ftrace: hotpatch support for function tracing ftrace: let notrace function attribute disable hotpatching if necessary ftrace: allow architectures to specify ftrace compile options s390: reintroduce diag 44 calls for cpu_relax() s390/zcrypt: Add support for new crypto express (CEX5S) adapter. s390/zcrypt: Number of supported ap domains is not retrievable. s390/spinlock: add compare-and-delay to lock wait loops s390/tape: remove redundant if statement s390/hvc_iucv: add simple wildcard matches to the iucv allow filter ...
| * | ftrace: allow architectures to specify ftrace compile optionsHeiko Carstens2015-01-291-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the kernel is compiled with function tracer support the -pg compile option is passed to gcc to generate extra code into the prologue of each function. This patch replaces the "open-coded" -pg compile flag with a CC_FLAGS_FTRACE makefile variable which architectures can override if a different option should be used for code generation. Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | | Merge tag 'pm+acpi-3.20-rc1' of ↵Linus Torvalds2015-02-111-0/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: "We have a few new features this time, including a new SFI-based cpufreq driver, a new devfreq driver for Tegra Activity Monitor, a new devfreq class for providing its governors with raw utilization data and a new ACPI driver for AMD SoCs. Still, the majority of changes here are reworks of existing code to make it more straightforward or to prepare it for implementing new features on top of it. The primary example is the rework of ACPI resources handling from Jiang Liu, Thomas Gleixner and Lv Zheng with support for IOAPIC hotplug implemented on top of it, but there is quite a number of changes of this kind in the cpufreq core, ACPICA, ACPI EC driver, ACPI processor driver and the generic power domains core code too. The most active developer is Viresh Kumar with his cpufreq changes. Specifics: - Rework of the core ACPI resources parsing code to fix issues in it and make using resource offsets more convenient and consolidation of some resource-handing code in a couple of places that have grown analagous data structures and code to cover the the same gap in the core (Jiang Liu, Thomas Gleixner, Lv Zheng). - ACPI-based IOAPIC hotplug support on top of the resources handling rework (Jiang Liu, Yinghai Lu). - ACPICA update to upstream release 20150204 including an interrupt handling rework that allows drivers to install raw handlers for ACPI GPEs which then become entirely responsible for the given GPE and the ACPICA core code won't touch it (Lv Zheng, David E Box, Octavian Purdila). - ACPI EC driver rework to fix several concurrency issues and other problems related to events handling on top of the ACPICA's new support for raw GPE handlers (Lv Zheng). - New ACPI driver for AMD SoCs analogous to the LPSS (Low-Power Subsystem) driver for Intel chips (Ken Xue). - Two minor fixes of the ACPI LPSS driver (Heikki Krogerus, Jarkko Nikula). - Two new blacklist entries for machines (Samsung 730U3E/740U3E and 510R) where the native backlight interface doesn't work correctly while the ACPI one does (Hans de Goede). - Rework of the ACPI processor driver's handling of idle states to make the code more straightforward and less bloated overall (Rafael J Wysocki). - Assorted minor fixes related to ACPI and SFI (Andreas Ruprecht, Andy Shevchenko, Hanjun Guo, Jan Beulich, Rafael J Wysocki, Yaowei Bai). - PCI core power management modification to avoid resuming (some) runtime-suspended devices during system suspend if they are in the right states already (Rafael J Wysocki). - New SFI-based cpufreq driver for Intel platforms using SFI (Srinidhi Kasagar). - cpufreq core fixes, cleanups and simplifications (Viresh Kumar, Doug Anderson, Wolfram Sang). - SkyLake CPU support and other updates for the intel_pstate driver (Kristen Carlson Accardi, Srinivas Pandruvada). - cpufreq-dt driver cleanup (Markus Elfring). - Init fix for the ARM big.LITTLE cpuidle driver (Sudeep Holla). - Generic power domains core code fixes and cleanups (Ulf Hansson). - Operating Performance Points (OPP) core code cleanups and kernel documentation update (Nishanth Menon). - New dabugfs interface to make the list of PM QoS constraints available to user space (Nishanth Menon). - New devfreq driver for Tegra Activity Monitor (Tomeu Vizoso). - New devfreq class (devfreq_event) to provide raw utilization data to devfreq governors (Chanwoo Choi). - Assorted minor fixes and cleanups related to power management (Andreas Ruprecht, Krzysztof Kozlowski, Rickard Strandqvist, Pavel Machek, Todd E Brandt, Wonhong Kwon). - turbostat updates (Len Brown) and cpupower Makefile improvement (Sriram Raghunathan)" * tag 'pm+acpi-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (151 commits) tools/power turbostat: relax dependency on APERF_MSR tools/power turbostat: relax dependency on invariant TSC Merge branch 'pci/host-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci into acpi-resources tools/power turbostat: decode MSR_*_PERF_LIMIT_REASONS tools/power turbostat: relax dependency on root permission ACPI / video: Add disable_native_backlight quirk for Samsung 510R ACPI / PM: Remove unneeded nested #ifdef USB / PM: Remove unneeded #ifdef and associated dead code intel_pstate: provide option to only use intel_pstate with HWP ACPI / EC: Add GPE reference counting debugging messages ACPI / EC: Add query flushing support ACPI / EC: Refine command storm prevention support ACPI / EC: Add command flushing support. ACPI / EC: Introduce STARTED/STOPPED flags to replace BLOCKED flag ACPI: add AMD ACPI2Platform device support for x86 system ACPI / table: remove duplicate NULL check for the handler of acpi_table_parse() ACPI / EC: Update revision due to raw handler mode. ACPI / EC: Reduce ec_poll() by referencing the last register access timestamp. ACPI / EC: Fix several GPE handling issues by deploying ACPI_GPE_DISPATCH_RAW_HANDLER mode. ACPICA: Events: Enable APIs to allow interrupt/polling adaptive request based GPE handling model ...
| * | | PM / sleep: export suspend_resume trace eventTodd E Brandt2015-01-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Export the suspend_resume tracepoint so it can be used in loadable modules. Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | | | Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar2015-01-283-23/+100
|\| | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | Merge tag 'trace-fixes-v3.19-rc3' of ↵Linus Torvalds2015-01-163-23/+100
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull ftrace fixes from Steven Rostedt: "This holds a few fixes to the ftrace infrastructure as well as the mixture of function graph tracing and kprobes. When jprobes and function graph tracing is enabled at the same time it will crash the system: # modprobe jprobe_example # echo function_graph > /sys/kernel/debug/tracing/current_tracer After the first fork (jprobe_example probes it), the system will crash. This is due to the way jprobes copies the stack frame and does not do a normal function return. This messes up with the function graph tracing accounting which hijacks the return address from the stack and replaces it with a hook function. It saves the return addresses in a separate stack to put back the correct return address when done. But because the jprobe functions do not do a normal return, their stack addresses are not put back until the function they probe is called, which means that the probed function will get the return address of the jprobe handler instead of its own. The simple fix here was to disable function graph tracing while the jprobe handler is being called. While debugging this I found two minor bugs with the function graph tracing. The first was about the function graph tracer sharing its function hash with the function tracer (they both get filtered by the same input). The changing of the set_ftrace_filter would not sync the function recording records after a change if the function tracer was disabled but the function graph tracer was enabled. This was due to the update only checking one of the ops instead of the shared ops to see if they were enabled and should perform the sync. This caused the ftrace accounting to break and a ftrace_bug() would be triggered, disabling ftrace until a reboot. The second was that the check to update records only checked one of the filter hashes. It needs to test both the "filter" and "notrace" hashes. The "filter" hash determines what functions to trace where as the "notrace" hash determines what functions not to trace (trace all but these). Both hashes need to be passed to the update code to find out what change is being done during the update. This also broke the ftrace record accounting and triggered a ftrace_bug(). This patch set also include two more fixes that were reported separately from the kprobe issue. One was that init_ftrace_syscalls() was called twice at boot up. This is not a major bug, but that call performed a rather large kmalloc (NR_syscalls * sizeof(*syscalls_metadata)). The second call made the first one a memory leak, and wastes memory. The other fix is a regression caused by an update in the v3.19 merge window. The moving to enable events early, moved the enabling before PID 1 was created. The syscall events require setting the TIF_SYSCALL_TRACEPOINT for all tasks. But for_each_process_thread() does not include the swapper task (PID 0), and ended up being a nop. A suggested fix was to add the init_task() to have its flag set, but I didn't really want to mess with PID 0 for this minor bug. Instead I disable and re-enable events again at early_initcall() where it use to be enabled. This also handles any other event that might have its own reg function that could break at early boot up" * tag 'trace-fixes-v3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Fix enabling of syscall events on the command line tracing: Remove extra call to init_ftrace_syscalls() ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracing ftrace: Check both notrace and filter for old hash ftrace: Fix updating of filters for shared global_ops filters
| | * | | tracing: Fix enabling of syscall events on the command lineSteven Rostedt (Red Hat)2015-01-151-14/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 5f893b2639b2 "tracing: Move enabling tracepoints to just after rcu_init()" broke the enabling of system call events from the command line. The reason was that the enabling of command line trace events was moved before PID 1 started, and the syscall tracepoints require that all tasks have the TIF_SYSCALL_TRACEPOINT flag set. But the swapper task (pid 0) is not part of that. Since the swapper task is the only task that is running at this early in boot, no task gets the flag set, and the tracepoint never gets reached. Instead of setting the swapper task flag (there should be no reason to do that), re-enabled trace events again after the init thread (PID 1) has been started. It requires disabling all command line events and re-enabling them, as just enabling them again will not reset the logic to set the TIF_SYSCALL_TRACEPOINT flag, as the syscall tracepoint will be fooled into thinking that it was already set, and wont try setting it again. For this reason, we must first disable it and re-enable it. Link: http://lkml.kernel.org/r/1421188517-18312-1-git-send-email-mpe@ellerman.id.au Link: http://lkml.kernel.org/r/20150115040506.216066449@goodmis.org Reported-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | tracing: Remove extra call to init_ftrace_syscalls()Steven Rostedt (Red Hat)2015-01-151-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | trace_init() calls init_ftrace_syscalls() and then calls trace_event_init() which also calls init_ftrace_syscalls(). It makes more sense to only call it from trace_event_init(). Calling it twice wastes memory, as it allocates the syscall events twice, and loses the first copy of it. Link: http://lkml.kernel.org/r/54AF53BD.5070303@huawei.com Link: http://lkml.kernel.org/r/20150115040505.930398632@goodmis.org Reported-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | ftrace: Check both notrace and filter for old hashSteven Rostedt (Red Hat)2015-01-151-7/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using just the filter for checking for trampolines or regs is not enough when updating the code against the records that represent all functions. Both the filter hash and the notrace hash need to be checked. To trigger this bug (using trace-cmd and perf): # perf probe -a do_fork # trace-cmd start -B foo -e probe # trace-cmd record -p function_graph -n do_fork sleep 1 The trace-cmd record at the end clears the filter before it disables function_graph tracing and then that causes the accounting of the ftrace function records to become incorrect and causes ftrace to bug. Link: http://lkml.kernel.org/r/20150114154329.358378039@goodmis.org Cc: stable@vger.kernel.org [ still need to switch old_hash_ops to old_ops_hash ] Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | ftrace: Fix updating of filters for shared global_ops filtersSteven Rostedt (Red Hat)2015-01-151-1/+25
| | | |/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the set_ftrace_filter affects both the function tracer as well as the function graph tracer, the ops that represent each have a shared ftrace_ops_hash structure. This allows both to be updated when the filter files are updated. But if function graph is enabled and the global_ops (function tracing) ops is not, then it is possible that the filter could be changed without the update happening for the function graph ops. This will cause the changes to not take place and may even cause a ftrace_bug to occur as it could mess with the trampoline accounting. The solution is to check if the ops uses the shared global_ops filter and if the ops itself is not enabled, to check if there's another ops that is enabled and also shares the global_ops filter. In that case, the modification still needs to be executed. Link: http://lkml.kernel.org/r/20150114154329.055980438@goodmis.org Cc: stable@vger.kernel.org # 3.17+ Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | / | perf: Avoid horrible stack usagePeter Zijlstra (Intel)2015-01-144-6/+8
|/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both Linus (most recent) and Steve (a while ago) reported that perf related callbacks have massive stack bloat. The problem is that software events need a pt_regs in order to properly report the event location and unwind stack. And because we could not assume one was present we allocated one on stack and filled it with minimal bits required for operation. Now, pt_regs is quite large, so this is undesirable. Furthermore it turns out that most sites actually have a pt_regs pointer available, making this even more onerous, as the stack space is pointless waste. This patch addresses the problem by observing that software events have well defined nesting semantics, therefore we can use static per-cpu storage instead of on-stack. Linus made the further observation that all but the scheduler callers of perf_sw_event() have a pt_regs available, so we change the regular perf_sw_event() to require a valid pt_regs (where it used to be optional) and add perf_sw_event_sched() for the scheduler. We have a scheduler specific call instead of a more generic _noregs() like construct because we can assume non-recursion from the scheduler and thereby simplify the code further (_noregs would have to put the recursion context call inline in order to assertain which __perf_regs element to use). One last note on the implementation of perf_trace_buf_prepare(); we allow .regs = NULL for those cases where we already have a pt_regs pointer available and do not need another. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Javi Merino <javi.merino@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Petr Mladek <pmladek@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Vaibhav Nagarnaik <vnagarnaik@google.com> Link: http://lkml.kernel.org/r/20141216115041.GW3337@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge tag 'for_linus-3.19-rc4' of ↵Linus Torvalds2015-01-101-2/+2
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb Pull kgdb/kdb fixes from Jason Wessel: "These have been around since 3.17 and in kgdb-next for the last 9 weeks and some will go back to -stable. Summary of changes: Cleanups - kdb: Remove unused command flags, repeat flags and KDB_REPEAT_NONE Fixes - kgdb/kdb: Allow access on a single core, if a CPU round up is deemed impossible, which will allow inspection of the now "trashed" kernel - kdb: Add enable mask for the command groups - kdb: access controls to restrict sensitive commands" * tag 'for_linus-3.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb: kernel/debug/debug_core.c: Logging clean-up kgdb: timeout if secondary CPUs ignore the roundup kdb: Allow access to sensitive commands to be restricted by default kdb: Add enable mask for groups of commands kdb: Categorize kdb commands (similar to SysRq categorization) kdb: Remove KDB_REPEAT_NONE flag kdb: Use KDB_REPEAT_* values as flags kdb: Rename kdb_register_repeat() to kdb_register_flags() kdb: Rename kdb_repeat_t to kdb_cmdflags_t, cmd_repeat to cmd_flags kdb: Remove currently unused kdbtab_t->cmd_flags
| * | kdb: Categorize kdb commands (similar to SysRq categorization)Daniel Thompson2014-11-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces several new flags to collect kdb commands into groups (later allowing them to be optionally disabled). This follows similar prior art to enable/disable magic sysrq commands. The commands have been categorized as follows: Always on: go (w/o args), env, set, help, ?, cpu (w/o args), sr, dmesg, disable_nmi, defcmd, summary, grephelp Mem read: md, mdr, mdp, mds, ef, bt (with args), per_cpu Mem write: mm Reg read: rd Reg write: go (with args), rm Inspect: bt (w/o args), btp, bta, btc, btt, ps, pid, lsmod Flow ctrl: bp, bl, bph, bc, be, bd, ss Signal: kill Reboot: reboot All: cpu, kgdb, (and all of the above), nmi_console Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | kdb: Remove KDB_REPEAT_NONE flagAnton Vorontsov2014-11-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since we now treat KDB_REPEAT_* as flags, there is no need to pass KDB_REPEAT_NONE. It's just the default behaviour when no flags are specified. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | kdb: Rename kdb_register_repeat() to kdb_register_flags()Anton Vorontsov2014-11-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We're about to add more options for commands behaviour, so let's give a more generic name to the low-level kdb command registration function. There are just various renames, no functional changes. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* | | Merge tag 'pm+acpi-3.19-rc1-2' of ↵Linus Torvalds2014-12-191-1/+1
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI and power management updates from Rafael Wysocki: "These are regression fixes (leds-gpio, ACPI backlight driver, operating performance points library, ACPI device enumeration messages, cpupower tool), other bug fixes (ACPI EC driver, ACPI device PM), some cleanups in the operating performance points (OPP) framework, continuation of CONFIG_PM_RUNTIME elimination, a couple of minor intel_pstate driver changes, a new MAINTAINERS entry for it and an ACPI fan driver change needed for better support of thermal management in user space. Specifics: - Fix a regression in leds-gpio introduced by a recent commit that inadvertently changed the name of one of the properties used by the driver (Fabio Estevam). - Fix a regression in the ACPI backlight driver introduced by a recent fix that missed one special case that had to be taken into account (Aaron Lu). - Drop the level of some new kernel messages from the ACPI core introduced by a recent commit to KERN_DEBUG which they should have used from the start and drop some other unuseful KERN_ERR messages printed by ACPI (Rafael J Wysocki). - Revert an incorrect commit modifying the cpupower tool (Prarit Bhargava). - Fix two regressions introduced by recent commits in the OPP library and clean up some existing minor issues in that code (Viresh Kumar). - Continue to replace CONFIG_PM_RUNTIME with CONFIG_PM throughout the tree (or drop it where that can be done) in order to make it possible to eliminate CONFIG_PM_RUNTIME (Rafael J Wysocki, Ulf Hansson, Ludovic Desroches). There will be one more "CONFIG_PM_RUNTIME removal" batch after this one, because some new uses of it have been introduced during the current merge window, but that should be sufficient to finally get rid of it. - Make the ACPI EC driver more robust against race conditions related to GPE handler installation failures (Lv Zheng). - Prevent the ACPI device PM core code from attempting to disable GPEs that it has not enabled which confuses ACPICA and makes it report errors unnecessarily (Rafael J Wysocki). - Add a "force" command line switch to the intel_pstate driver to make it possible to override the blacklisting of some systems in that driver if needed (Ethan Zhao). - Improve intel_pstate code documentation and add a MAINTAINERS entry for it (Kristen Carlson Accardi). - Make the ACPI fan driver create cooling device interfaces witn names that reflect the IDs of the ACPI device objects they are associated with, except for "generic" ACPI fans (PNP ID "PNP0C0B"). That's necessary for user space thermal management tools to be able to connect the fans with the parts of the system they are supposed to be cooling properly. From Srinivas Pandruvada" * tag 'pm+acpi-3.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits) MAINTAINERS: add entry for intel_pstate ACPI / video: update the skip case for acpi_video_device_in_dod() power / PM: Eliminate CONFIG_PM_RUNTIME NFC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM SCSI / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM ACPI / EC: Fix unexpected ec_remove_handlers() invocations Revert "tools: cpupower: fix return checks for sysfs_get_idlestate_count()" tracing / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM x86 / PM: Replace CONFIG_PM_RUNTIME in io_apic.c PM: Remove the SET_PM_RUNTIME_PM_OPS() macro mmc: atmel-mci: use SET_RUNTIME_PM_OPS() macro PM / Kconfig: Replace PM_RUNTIME with PM in dependencies ARM / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM sound / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM phy / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM video / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM tty / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM spi: Replace CONFIG_PM_RUNTIME with CONFIG_PM ACPI / PM: Do not disable wakeup GPEs that have not been enabled ACPI / utils: Drop error messages from acpi_evaluate_reference() ...
| * | tracing / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PMRafael J. Wysocki2014-12-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit b2b49ccbdd54 (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so files that are build conditionally if CONFIG_PM_RUNTIME is set may now be build if CONFIG_PM is set. Replace CONFIG_PM_RUNTIME with CONFIG_PM in kernel/trace/Makefile for this reason. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Steven Rostedt <rostedt@goodmis.org.
* | | Merge tag 'trace-3.19-2' of ↵Linus Torvalds2014-12-164-8/+80
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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()
| * | | tracing: Add tp_printk cmdline to have tracepoints go to printk()Steven Rostedt (Red Hat)2014-12-153-0/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the kernel command line tp_printk option that will have tracepoints that are active sent to printk() as well as to the trace buffer. Passing "tp_printk" will activate this. To turn it off, the sysctl /proc/sys/kernel/tracepoint_printk can have '0' echoed into it. Note, this only works if the cmdline option is used. Echoing 1 into the sysctl file without the cmdline option will have no affect. Note, this is a dangerous option. Having high frequency tracepoints send their data to printk() can possibly cause a live lock. This is another reason why this is only active if the command line option is used. Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1412121539300.16494@nanos 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>
| * | | tracing: Move enabling tracepoints to just after rcu_init()Steven Rostedt (Red Hat)2014-12-154-8/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | Merge branch 'for-3.19/core' of git://git.kernel.dk/linux-blockLinus Torvalds2014-12-131-3/+0
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block driver core update from Jens Axboe: "This is the pull request for the core block IO changes for 3.19. Not a huge round this time, mostly lots of little good fixes: - Fix a bug in sysfs blktrace interface causing a NULL pointer dereference, when enabled/disabled through that API. From Arianna Avanzini. - Various updates/fixes/improvements for blk-mq: - A set of updates from Bart, mostly fixing buts in the tag handling. - Cleanup/code consolidation from Christoph. - Extend queue_rq API to be able to handle batching issues of IO requests. NVMe will utilize this shortly. From me. - A few tag and request handling updates from me. - Cleanup of the preempt handling for running queues from Paolo. - Prevent running of unmapped hardware queues from Ming Lei. - Move the kdump memory limiting check to be in the correct location, from Shaohua. - Initialize all software queues at init time from Takashi. This prevents a kobject warning when CPUs are brought online that weren't online when a queue was registered. - Single writeback fix for I_DIRTY clearing from Tejun. Queued with the core IO changes, since it's just a single fix. - Version X of the __bio_add_page() segment addition retry from Maurizio. Hope the Xth time is the charm. - Documentation fixup for IO scheduler merging from Jan. - Introduce (and use) generic IO stat accounting helpers for non-rq drivers, from Gu Zheng. - Kill off artificial limiting of max sectors in a request from Christoph" * 'for-3.19/core' of git://git.kernel.dk/linux-block: (26 commits) bio: modify __bio_add_page() to accept pages that don't start a new segment blk-mq: Fix uninitialized kobject at CPU hotplugging blktrace: don't let the sysfs interface remove trace from running list blk-mq: Use all available hardware queues blk-mq: Micro-optimize bt_get() blk-mq: Fix a race between bt_clear_tag() and bt_get() blk-mq: Avoid that __bt_get_word() wraps multiple times blk-mq: Fix a use-after-free blk-mq: prevent unmapped hw queue from being scheduled blk-mq: re-check for available tags after running the hardware queue blk-mq: fix hang in bt_get() blk-mq: move the kdump check to blk_mq_alloc_tag_set blk-mq: cleanup tag free handling blk-mq: use 'nr_cpu_ids' as highest CPU ID count for hwq <-> cpu map blk: introduce generic io stat accounting help function blk-mq: handle the single queue case in blk_mq_hctx_next_cpu genhd: check for int overflow in disk_expand_part_tbl() blk-mq: add blk_mq_free_hctx_request() blk-mq: export blk_mq_free_request() blk-mq: use get_cpu/put_cpu instead of preempt_disable/preempt_enable ...
| * | | | blktrace: don't let the sysfs interface remove trace from running listArianna Avanzini2014-12-091-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, blktrace can be started/stopped via its ioctl-based interface (used by the userspace blktrace tool) or via its ftrace interface. The function blk_trace_remove_queue(), called each time an "enable" tunable of the ftrace interface transitions to zero, removes the trace from the running list, even if no function from the sysfs interface adds it to such a list. This leads to a null pointer dereference. This commit changes the blk_trace_remove_queue() function so that it does not remove the blk_trace from the running list. v2: - Now the patch removes the invocation of list_del() instead of adding an useless if branch, as suggested by Namhyung Kim. Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* | | | | Merge branch 'for-linus' of ↵Linus Torvalds2014-12-121-1/+1
|\ \ \ \ \ | |_|_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree update from Jiri Kosina: "Usual stuff: documentation updates, printk() fixes, etc" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits) intel_ips: fix a type in error message cpufreq: cpufreq-dt: Move newline to end of error message ps3rom: fix error return code treewide: fix typo in printk and Kconfig ARM: dts: bcm63138: change "interupts" to "interrupts" Replace mentions of "list_struct" to "list_head" kernel: trace: fix printk message scsi: mpt2sas: fix ioctl in comment zbud, zswap: change module author email clocksource: Fix 'clcoksource' typo in comment arm: fix wording of "Crotex" in CONFIG_ARCH_EXYNOS3 help gpio: msm-v1: make boolean argument more obvious usb: Fix typo in usb-serial-simple.c PCI: Fix comment typo 'COMFIG_PM_OPS' powerpc: Fix comment typo 'CONIFG_8xx' powerpc: Fix comment typos 'CONFiG_ALTIVEC' clk: st: Spelling s/stucture/structure/ isci: Spelling s/stucture/structure/ usb: gadget: zero: Spelling s/infrastucture/infrastructure/ treewide: Fix company name in module descriptions ...
| * | | | Merge Linus' tree to be be to apply submitted patches to newer code thanJiri Kosina2014-11-208-336/+540
| |\ \ \ \ | | | | | | | | | | | | | | | | | | current trivial.git base
| * | | | | kernel: trace: fix printk messageFrans Klaver2014-11-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | s,produciton,production Signed-off-by: Frans Klaver <frans.klaver@xsens.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | | | | | Merge tag 'trace-seq-buf-3.19' of ↵Linus Torvalds2014-12-114-122/+140
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull nmi-safe seq_buf printk update from Steven Rostedt: "This code is a fork from the trace-3.19 pull as it needed the trace_seq clean ups from that branch. This code solves the issue of performing stack dumps from NMI context. The issue is that printk() is not safe from NMI context as if the NMI were to trigger when a printk() was being performed, the NMI could deadlock from the printk() internal locks. This has been seen in practice. With lots of review from Petr Mladek, this code went through several iterations, and we feel that it is now at a point of quality to be accepted into mainline. Here's what is contained in this patch set: - Creates a "seq_buf" generic buffer utility that allows a descriptor to be passed around where functions can write their own "printk()" formatted strings into it. The generic version was pulled out of the trace_seq() code that was made specifically for tracing. - The seq_buf code was change to model the seq_file code. I have a patch (not included for 3.19) that converts the seq_file.c code over to use seq_buf.c like the trace_seq.c code does. This was done to make sure that seq_buf.c is compatible with seq_file.c. I may try to get that patch in for 3.20. - The seq_buf.c file was moved to lib/ to remove it from being dependent on CONFIG_TRACING. - The printk() was updated to allow for a per_cpu "override" of the internal calls. That is, instead of writing to the console, a call to printk() may do something else. This made it easier to allow the NMI to change what printk() does in order to call dump_stack() without needing to update that code as well. - Finally, the dump_stack from all CPUs via NMI code was converted to use the seq_buf code. The caller to trigger the NMI code would wait till all the NMIs finished, and then it would print the seq_buf data to the console safely from a non NMI context One added bonus is that this code also makes the NMI dump stack work on PREEMPT_RT kernels. As printk() includes sleeping locks on PREEMPT_RT, printk() only writes to console if the console does not use any rt_mutex converted spin locks. Which a lot do" * tag 'trace-seq-buf-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: x86/nmi: Fix use of unallocated cpumask_var_t printk/percpu: Define printk_func when printk is not defined x86/nmi: Perform a safe NMI stack trace on all CPUs printk: Add per_cpu printk func to allow printk to be diverted seq_buf: Move the seq_buf code to lib/ seq-buf: Make seq_buf_bprintf() conditional on CONFIG_BINARY_PRINTF tracing: Add seq_buf_get_buf() and seq_buf_commit() helper functions tracing: Have seq_buf use full buffer seq_buf: Add seq_buf_can_fit() helper function tracing: Add paranoid size check in trace_printk_seq() tracing: Use trace_seq_used() and seq_buf_used() instead of len tracing: Clean up tracing_fill_pipe_page() seq_buf: Create seq_buf_used() to find out how much was written tracing: Add a seq_buf_clear() helper and clear len and readpos in init tracing: Convert seq_buf fields to be like seq_file fields tracing: Convert seq_buf_path() to be like seq_path() tracing: Create seq_buf layer in trace_seq
| * | | | | | seq_buf: Move the seq_buf code to lib/Steven Rostedt (Red Hat)2014-11-202-360/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The seq_buf functions are rather useful outside of tracing. Instead of having it be dependent on CONFIG_TRACING, move the code into lib/ and allow other users to have access to it even when tracing is not configured. The seq_buf utility is similar to the seq_file utility, but instead of writing sending data back up to userland, it writes it into a buffer defined at seq_buf_init(). This allows us to send a descriptor around that writes printf() formatted strings into it that can be retrieved later. It is currently used by the tracing facility for such things like trace events to convert its binary saved data in the ring buffer into an ASCII human readable context to be displayed in /sys/kernel/debug/trace. It can also be used for doing NMI prints safely from NMI context into the seq_buf and retrieved later and dumped to printk() safely. Doing printk() from an NMI context is dangerous because an NMI can preempt a current printk() and deadlock on it. Link: http://lkml.kernel.org/p/20140619213952.058255809@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | seq-buf: Make seq_buf_bprintf() conditional on CONFIG_BINARY_PRINTFSteven Rostedt (Red Hat)2014-11-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function bstr_printf() from lib/vsprnintf.c is only available if CONFIG_BINARY_PRINTF is defined. This is due to the only user currently being the tracing infrastructure, which needs to select this config when tracing is configured. Until there is another user of the binary printf formats, this will continue to be the case. Since seq_buf.c is now lives in lib/ and is compiled even without tracing, it must encompass its use of bstr_printf() which is used by seq_buf_printf(). This too is only used by the tracing infrastructure and is still encapsulated by the CONFIG_BINARY_PRINTF. Link: http://lkml.kernel.org/r/20141104160222.969013383@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | tracing: Add seq_buf_get_buf() and seq_buf_commit() helper functionsSteven Rostedt (Red Hat)2014-11-201-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add two helper functions; seq_buf_get_buf() and seq_buf_commit() that are used by seq_buf_path(). This makes the code similar to the seq_file: seq_path() function, and will help to be able to consolidate the functions between seq_file and trace_seq. Link: http://lkml.kernel.org/r/20141104160222.644881406@goodmis.org Link: http://lkml.kernel.org/r/20141114011412.977571447@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | tracing: Have seq_buf use full bufferSteven Rostedt (Red Hat)2014-11-201-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently seq_buf is full when all but one byte of the buffer is filled. Change it so that the seq_buf is full when all of the buffer is filled. Some of the functions would fill the buffer completely and report everything was fine. This was inconsistent with the max of size - 1. Changing this to be max of size makes all functions consistent. Link: http://lkml.kernel.org/r/20141104160222.502133196@goodmis.org Link: http://lkml.kernel.org/r/20141114011412.811957882@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | seq_buf: Add seq_buf_can_fit() helper functionSteven Rostedt (Red Hat)2014-11-201-5/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a seq_buf_can_fit() helper function that removes the possible mistakes of comparing the seq_buf length plus added data compared to the size of the buffer. Link: http://lkml.kernel.org/r/20141118164025.GL23958@pathway.suse.cz Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | tracing: Add paranoid size check in trace_printk_seq()Steven Rostedt (Red Hat)2014-11-201-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To be really paranoid about writing out of bound data in trace_printk_seq(), add another check of len compared to size. Link: http://lkml.kernel.org/r/20141119144004.GB2332@dhcp128.suse.cz Suggested-by: Petr Mladek <pmladek@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | tracing: Use trace_seq_used() and seq_buf_used() instead of lenSteven Rostedt (Red Hat)2014-11-205-16/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the seq_buf->len will soon be +1 size when there's an overflow, we must use trace_seq_used() or seq_buf_used() methods to get the real length. This will prevent buffer overflow issues if just the len of the seq_buf descriptor is used to copy memory. Link: http://lkml.kernel.org/r/20141114121911.09ba3d38@gandalf.local.home Reported-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | tracing: Clean up tracing_fill_pipe_page()Steven Rostedt (Red Hat)2014-11-201-6/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function tracing_fill_pipe_page() logic is a little confusing with the use of count saving the seq.len and reusing it. Instead of subtracting a number that is calculated from the saved value of the seq.len from seq.len, just save the seq.len at the start and if we need to reset it, just assign it again. When the seq_buf overflow is len == size + 1, the current logic will break. Changing it to use a saved length for resetting back to the original value is more robust and will work when we change the way seq_buf sets the overflow. Link: http://lkml.kernel.org/r/20141118161546.GJ23958@pathway.suse.cz Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | seq_buf: Create seq_buf_used() to find out how much was writtenSteven Rostedt (Red Hat)2014-11-201-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a helper function seq_buf_used() that replaces the SEQ_BUF_USED() private macro to let callers have a method to know how much of the seq_buf was written to. Link: http://lkml.kernel.org/r/20141114011412.170377300@goodmis.org Link: http://lkml.kernel.org/r/20141114011413.321654244@goodmis.org Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | tracing: Convert seq_buf_path() to be like seq_path()Steven Rostedt (Red Hat)2014-11-202-15/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rewrite seq_buf_path() like it is done in seq_path() and allow it to accept any escape character instead of just "\n". Making seq_buf_path() like seq_path() will help prevent problems when converting seq_file to use the seq_buf logic. Link: http://lkml.kernel.org/r/20141104160222.048795666@goodmis.org Link: http://lkml.kernel.org/r/20141114011412.338523371@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | | | tracing: Create seq_buf layer in trace_seqSteven Rostedt (Red Hat)2014-11-206-119/+452
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Create a seq_buf layer that trace_seq sits on. The seq_buf will not be limited to page size. This will allow other usages of seq_buf instead of a hard set PAGE_SIZE one that trace_seq has. Link: http://lkml.kernel.org/r/20141104160221.864997179@goodmis.org Link: http://lkml.kernel.org/r/20141114011412.170377300@goodmis.org Tested-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | | | | | Merge tag 'trace-3.19' of ↵Linus Torvalds2014-12-1123-1175/+1125
|\ \ \ \ \ \ \ | | |_|_|_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "There was a lot of clean ups and minor fixes. One of those clean ups was to the trace_seq code. It also removed the return values to the trace_seq_*() functions and use trace_seq_has_overflowed() to see if the buffer filled up or not. This is similar to work being done to the seq_file code as well in another tree. Some of the other goodies include: - Added some "!" (NOT) logic to the tracing filter. - Fixed the frame pointer logic to the x86_64 mcount trampolines - Added the logic for dynamic trampolines on !CONFIG_PREEMPT systems. That is, the ftrace trampoline can be dynamically allocated and be called directly by functions that only have a single hook to them" * tag 'trace-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (55 commits) tracing: Truncated output is better than nothing tracing: Add additional marks to signal very large time deltas Documentation: describe trace_buf_size parameter more accurately tracing: Allow NOT to filter AND and OR clauses tracing: Add NOT to filtering logic ftrace/fgraph/x86: Have prepare_ftrace_return() take ip as first parameter ftrace/x86: Get rid of ftrace_caller_setup ftrace/x86: Have save_mcount_regs macro also save stack frames if needed ftrace/x86: Add macro MCOUNT_REG_SIZE for amount of stack used to save mcount regs ftrace/x86: Simplify save_mcount_regs on getting RIP ftrace/x86: Have save_mcount_regs store RIP in %rdi for first parameter ftrace/x86: Rename MCOUNT_SAVE_FRAME and add more detailed comments ftrace/x86: Move MCOUNT_SAVE_FRAME out of header file ftrace/x86: Have static tracing also use ftrace_caller_setup ftrace/x86: Have static function tracing always test for function graph kprobes: Add IPMODIFY flag to kprobe_ftrace_ops ftrace, kprobes: Support IPMODIFY flag to find IP modify conflict kprobes/ftrace: Recover original IP if pre_handler doesn't change it tracing/trivial: Fix typos and make an int into a bool tracing: Deletion of an unnecessary check before iput() ...