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2014-07-18tracing: Remove function_trace_stop and HAVE_FUNCTION_TRACE_MCOUNT_TESTSteven Rostedt (Red Hat)
All users of function_trace_stop and HAVE_FUNCTION_TRACE_MCOUNT_TEST have been removed. We can safely remove them from the kernel. Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-05-29tracing: Add tracepoint benchmark tracepointSteven Rostedt (Red Hat)
In order to help benchmark the time tracepoints take, a new config option is added called CONFIG_TRACEPOINT_BENCHMARK. When this option is set a tracepoint is created called "benchmark:benchmark_event". When the tracepoint is enabled, it kicks off a kernel thread that goes into an infinite loop (calling cond_sched() to let other tasks run), and calls the tracepoint. Each iteration will record the time it took to write to the tracepoint and the next iteration that data will be passed to the tracepoint itself. That is, the tracepoint will report the time it took to do the previous tracepoint. The string written to the tracepoint is a static string of 128 bytes to keep the time the same. The initial string is simply a write of "START". The second string records the cold cache time of the first write which is not added to the rest of the calculations. As it is a tight loop, it benchmarks as hot cache. That's fine because we care most about hot paths that are probably in cache already. An example of the output: START first=3672 [COLD CACHED] last=632 first=3672 max=632 min=632 avg=316 std=446 std^2=199712 last=278 first=3672 max=632 min=278 avg=303 std=316 std^2=100337 last=277 first=3672 max=632 min=277 avg=296 std=258 std^2=67064 last=273 first=3672 max=632 min=273 avg=292 std=224 std^2=50411 last=273 first=3672 max=632 min=273 avg=288 std=200 std^2=40389 last=281 first=3672 max=632 min=273 avg=287 std=183 std^2=33666 Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-18uprobes: Kconfig dependency fixDavid A. Long
Suggested change from Oleg Nesterov. Fixes incomplete dependencies for uprobes feature. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Oleg Nesterov <oleg@redhat.com>
2013-05-03ring-buffer: Select IRQ_WORKSteven Rostedt (Red Hat)
As the wake up logic for waiters on the buffer has been moved from the tracing code to the ring buffer, it requires also adding IRQ_WORK as the wake up code is performed via irq_work. This fixes compile breakage when a user of the ring buffer is selected but tracing and irq_work are not. Link http://lkml.kernel.org/r/20130503115332.GT8356@rric.localhost Cc: Arnd Bergmann <arnd@arndb.de> Reported-by: Robert Richter <rric@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-04-29Merge tag 'trace-3.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "Along with the usual minor fixes and clean ups there are a few major changes with this pull request. 1) Multiple buffers for the ftrace facility This feature has been requested by many people over the last few years. I even heard that Google was about to implement it themselves. I finally had time and cleaned up the code such that you can now create multiple instances of the ftrace buffer and have different events go to different buffers. This way, a low frequency event will not be lost in the noise of a high frequency event. Note, currently only events can go to different buffers, the tracers (ie function, function_graph and the latency tracers) still can only be written to the main buffer. 2) The function tracer triggers have now been extended. The function tracer had two triggers. One to enable tracing when a function is hit, and one to disable tracing. Now you can record a stack trace on a single (or many) function(s), take a snapshot of the buffer (copy it to the snapshot buffer), and you can enable or disable an event to be traced when a function is hit. 3) A perf clock has been added. A "perf" clock can be chosen to be used when tracing. This will cause ftrace to use the same clock as perf uses, and hopefully this will make it easier to interleave the perf and ftrace data for analysis." * tag 'trace-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (82 commits) tracepoints: Prevent null probe from being added tracing: Compare to 1 instead of zero for is_signed_type() tracing: Remove obsolete macro guard _TRACE_PROFILE_INIT ftrace: Get rid of ftrace_profile_bits tracing: Check return value of tracing_init_dentry() tracing: Get rid of unneeded key calculation in ftrace_hash_move() tracing: Reset ftrace_graph_filter_enabled if count is zero tracing: Fix off-by-one on allocating stat->pages kernel: tracing: Use strlcpy instead of strncpy tracing: Update debugfs README file tracing: Fix ftrace_dump() tracing: Rename trace_event_mutex to trace_event_sem tracing: Fix comment about prefix in arch_syscall_match_sym_name() tracing: Convert trace_destroy_fields() to static tracing: Move find_event_field() into trace_events.c tracing: Use TRACE_MAX_PRINT instead of constant tracing: Use pr_warn_once instead of open coded implementation ring-buffer: Add ring buffer startup selftest tracing: Bring Documentation/trace/ftrace.txt up to date tracing: Add "perf" trace_clock ... Conflicts: kernel/trace/ftrace.c kernel/trace/trace.c
2013-03-15ring-buffer: Add ring buffer startup selftestSteven Rostedt (Red Hat)
When testing my large changes to the ftrace system, there was a bug that looked like the ring buffer was dropping events. I wrote up a quick integrity checker of the ring buffer to see if it was. Although the bug ended up being something stupid I did in ftrace, and had nothing to do with the ring buffer, I figured if I spent the time to write up this test, I might as well include it in the kernel. I cleaned it up a bit, as the original version was rather ugly. Not saying this version is pretty, but it's a beauty queen compared to what I original wrote. To enable the start up test, set CONFIG_RING_BUFFER_STARTUP_TEST. Note, it runs for 10 seconds, so it will slow your boot time by at least 10 more seconds. What it does is documented in both the comments and the Kconfig help. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-15tracing: Add config option to allow snapshot to swap per cpuSteven Rostedt (Red Hat)
When the preempt or irq latency tracers are enabled, they require the ring buffer to be able to swap the per cpu sub buffers between two main buffers. This adds a slight overhead to tracing as the trace recording needs to perform some checks to synchronize between recording and swaps that might be happening on other CPUs. The config RING_BUFFER_ALLOW_SWAP is set when a user of the ring buffer needs the "swap cpu" feature, otherwise the extra checks are not implemented and removed from the tracing overhead. The snapshot feature will swap per CPU if the RING_BUFFER_ALLOW_SWAP config is set. But that only gets set by things like OPROFILE and the irqs and preempt latency tracers. This config is added to let the user decide to include this feature with the snapshot agnostic from whether or not another user of the ring buffer sets this config. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-15tracing: Enable snapshot when any latency tracer is enabledSteven Rostedt (Red Hat)
The snapshot utility is extremely useful, and does not add any more overhead in memory when another latency tracer is enabled. They use the snapshot underneath. There's no reason to hide the snapshot file when a latency tracer has been enabled in the kernel. If any of the latency tracers (irq, preempt or wakeup) is enabled then also select the snapshot facility. Note, snapshot can be enabled without the latency tracers enabled. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-11Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Misc minor fixes mostly related to tracing" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: s390: Fix a header dependencies related build error tracing: update documentation of snapshot utility tracing: Do not return EINVAL in snapshot when not allocated tracing: Add help of snapshot feature when snapshot is empty ftrace: Update the kconfig for DYNAMIC_FTRACE
2013-02-27ftrace: Update the kconfig for DYNAMIC_FTRACESteven Rostedt
The prompt to enable DYNAMIC_FTRACE (the ability to nop and enable function tracing at run time) had a confusing statement: "enable/disable ftrace tracepoints dynamically" This was written before tracepoints were added to the kernel, but now that tracepoints have been added, this is very confusing and has confused people enough to give wrong information during presentations. Not only that, I looked at the help text, and it still references that dreaded daemon that use to wake up once a second to update the nop locations and brick NICs, that hasn't been around for over five years. Time to bring the text up to the current decade. Cc: stable@vger.kernel.org Reported-by: Ezequiel Garcia <elezegarcia@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-02-20Merge tag 'pm+acpi-3.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: - Rework of the ACPI namespace scanning code from Rafael J. Wysocki with contributions from Bjorn Helgaas, Jiang Liu, Mika Westerberg, Toshi Kani, and Yinghai Lu. - ACPI power resources handling and ACPI device PM update from Rafael J Wysocki. - ACPICA update to version 20130117 from Bob Moore and Lv Zheng with contributions from Aaron Lu, Chao Guan, Jesper Juhl, and Tim Gardner. - Support for Intel Lynxpoint LPSS from Mika Westerberg. - cpuidle update from Len Brown including Intel Haswell support, C1 state for intel_idle, removal of global pm_idle. - cpuidle fixes and cleanups from Daniel Lezcano. - cpufreq fixes and cleanups from Viresh Kumar and Fabio Baltieri with contributions from Stratos Karafotis and Rickard Andersson. - Intel P-states driver for Sandy Bridge processors from Dirk Brandewie. - cpufreq driver for Marvell Kirkwood SoCs from Andrew Lunn. - cpufreq fixes related to ordering issues between acpi-cpufreq and powernow-k8 from Borislav Petkov and Matthew Garrett. - cpufreq support for Calxeda Highbank processors from Mark Langsdorf and Rob Herring. - cpufreq driver for the Freescale i.MX6Q SoC and cpufreq-cpu0 update from Shawn Guo. - cpufreq Exynos fixes and cleanups from Jonghwan Choi, Sachin Kamat, and Inderpal Singh. - Support for "lightweight suspend" from Zhang Rui. - Removal of the deprecated power trace API from Paul Gortmaker. - Assorted updates from Andreas Fleig, Colin Ian King, Davidlohr Bueso, Joseph Salisbury, Kees Cook, Li Fei, Nishanth Menon, ShuoX Liu, Srinivas Pandruvada, Tejun Heo, Thomas Renninger, and Yasuaki Ishimatsu. * tag 'pm+acpi-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (267 commits) PM idle: remove global declaration of pm_idle unicore32 idle: delete stray pm_idle comment openrisc idle: delete pm_idle mn10300 idle: delete pm_idle microblaze idle: delete pm_idle m32r idle: delete pm_idle, and other dead idle code ia64 idle: delete pm_idle cris idle: delete idle and pm_idle ARM64 idle: delete pm_idle ARM idle: delete pm_idle blackfin idle: delete pm_idle sparc idle: rename pm_idle to sparc_idle sh idle: rename global pm_idle to static sh_idle x86 idle: rename global pm_idle to static x86_idle APM idle: register apm_cpu_idle via cpuidle cpufreq / intel_pstate: Add kernel command line option disable intel_pstate. cpufreq / intel_pstate: Change to disallow module build tools/power turbostat: display SMI count by default intel_idle: export both C1 and C1E ACPI / hotplug: Fix concurrency issues and memory leaks ...
2013-01-30tracing: Make a snapshot feature available from userspaceHiraku Toyooka
Ftrace has a snapshot feature available from kernel space and latency tracers (e.g. irqsoff) are using it. This patch enables user applictions to take a snapshot via debugfs. Add "snapshot" debugfs file in "tracing" directory. snapshot: This is used to take a snapshot and to read the output of the snapshot. # echo 1 > snapshot This will allocate the spare buffer for snapshot (if it is not allocated), and take a snapshot. # cat snapshot This will show contents of the snapshot. # echo 0 > snapshot This will free the snapshot if it is allocated. Any other positive values will clear the snapshot contents if the snapshot is allocated, or return EINVAL if it is not allocated. Link: http://lkml.kernel.org/r/20121226025300.3252.86850.stgit@liselsia Cc: Jiri Olsa <jolsa@redhat.com> Cc: David Sharp <dhsharp@google.com> Signed-off-by: Hiraku Toyooka <hiraku.toyooka.gu@hitachi.com> [ Fixed irqsoff selftest and also a conflict with a change that fixes the update_max_tr. ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-01-26PM / tracing: remove deprecated power trace APIPaul Gortmaker
The text in Documentation said it would be removed in 2.6.41; the text in the Kconfig said removal in the 3.1 release. Either way you look at it, we are well past both, so push it off a cliff. Note that the POWER_CSTATE and the POWER_PSTATE are part of the legacy tracing API. Remove all tracepoints which use these flags. As can be seen from context, most already have a trace entry via trace_cpu_idle anyways. Also, the cpufreq/cpufreq.c PSTATE one is actually unpaired, as compared to the CSTATE ones which all have a clear start/stop. As part of this, the trace_power_frequency also becomes orphaned, so it too is deleted. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-21ftrace: Move ARCH_SUPPORTS_FTRACE_SAVE_REGS in KconfigMasami Hiramatsu
Move SAVE_REGS support flag into Kconfig and rename it to CONFIG_DYNAMIC_FTRACE_WITH_REGS. This also introduces CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS which indicates the architecture depending part of ftrace has a code that saves full registers. On the other hand, CONFIG_DYNAMIC_FTRACE_WITH_REGS indicates the code is enabled. Link: http://lkml.kernel.org/r/20120928081516.3560.72534.stgit@ltc138.sdl.hitachi.co.jp Cc: Ingo Molnar <mingo@elte.hu> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-11-02tracing: Use irq_work for wake ups and remove *_nowake_*() functionsSteven Rostedt
Have the ring buffer commit function use the irq_work infrastructure to wake up any waiters waiting on the ring buffer for new data. The irq_work was created for such a purpose, where doing the actual wake up at the time of adding data is too dangerous, as an event or function trace may be in the midst of the work queue locks and cause deadlocks. The irq_work will either delay the action to the next timer interrupt, or trigger an IPI to itself forcing an interrupt to do the work (in a safe location). With irq_work, all ring buffer commits can safely do wakeups, removing the need for the ring buffer commit "nowake" variants, which were used by events and function tracing. All commits can now safely use the normal commit, and the "nowake" variants can be removed. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-09-13trace: Stop compiling in trace_clock unconditionallyJosh Triplett
Commit 56449f437 "tracing: make the trace clocks available generally", in April 2009, made trace_clock available unconditionally, since CONFIG_X86_DS used it too. Commit faa4602e47 "x86, perf, bts, mm: Delete the never used BTS-ptrace code", in March 2010, removed CONFIG_X86_DS, and now only CONFIG_RING_BUFFER (split out from CONFIG_TRACING for general use) has a dependency on trace_clock. So, only compile in trace_clock with CONFIG_RING_BUFFER or CONFIG_TRACING enabled. Link: http://lkml.kernel.org/r/20120903024513.GA19583@leaf Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-23ftrace: Add -mfentry to Makefile on function tracerSteven Rostedt
Thanks to Andi Kleen, gcc 4.6.0 now supports -mfentry for x86 (and hopefully soon for other archs). What this does is to have the function profiler start at the beginning of the function instead of after the stack is set up. As plain -pg (mcount) is called after the stack is set up, and in some cases can have issues with the function graph tracer. It also requires frame pointers to be enabled. The -mfentry now calls __fentry__ at the beginning of the function. This allows for compiling without frame pointers and even has the ability to access parameters if needed. If the architecture and the compiler both support -mfentry then use that instead. Link: http://lkml.kernel.org/r/20120807194059.392617243@goodmis.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-05-24Merge branch 'perf-uprobes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull user-space probe instrumentation from Ingo Molnar: "The uprobes code originates from SystemTap and has been used for years in Fedora and RHEL kernels. This version is much rewritten, reviews from PeterZ, Oleg and myself shaped the end result. This tree includes uprobes support in 'perf probe' - but SystemTap (and other tools) can take advantage of user probe points as well. Sample usage of uprobes via perf, for example to profile malloc() calls without modifying user-space binaries. First boot a new kernel with CONFIG_UPROBE_EVENT=y enabled. If you don't know which function you want to probe you can pick one from 'perf top' or can get a list all functions that can be probed within libc (binaries can be specified as well): $ perf probe -F -x /lib/libc.so.6 To probe libc's malloc(): $ perf probe -x /lib64/libc.so.6 malloc Added new event: probe_libc:malloc (on 0x7eac0) You can now use it in all perf tools, such as: perf record -e probe_libc:malloc -aR sleep 1 Make use of it to create a call graph (as the flat profile is going to look very boring): $ perf record -e probe_libc:malloc -gR make [ perf record: Woken up 173 times to write data ] [ perf record: Captured and wrote 44.190 MB perf.data (~1930712 $ perf report | less 32.03% git libc-2.15.so [.] malloc | --- malloc 29.49% cc1 libc-2.15.so [.] malloc | --- malloc | |--0.95%-- 0x208eb1000000000 | |--0.63%-- htab_traverse_noresize 11.04% as libc-2.15.so [.] malloc | --- malloc | 7.15% ld libc-2.15.so [.] malloc | --- malloc | 5.07% sh libc-2.15.so [.] malloc | --- malloc | 4.99% python-config libc-2.15.so [.] malloc | --- malloc | 4.54% make libc-2.15.so [.] malloc | --- malloc | |--7.34%-- glob | | | |--93.18%-- 0x41588f | | | --6.82%-- glob | 0x41588f ... Or: $ perf report -g flat | less # Overhead Command Shared Object Symbol # ........ ............. ............. .......... # 32.03% git libc-2.15.so [.] malloc 27.19% malloc 29.49% cc1 libc-2.15.so [.] malloc 24.77% malloc 11.04% as libc-2.15.so [.] malloc 11.02% malloc 7.15% ld libc-2.15.so [.] malloc 6.57% malloc ... The core uprobes design is fairly straightforward: uprobes probe points register themselves at (inode:offset) addresses of libraries/binaries, after which all existing (or new) vmas that map that address will have a software breakpoint injected at that address. vmas are COW-ed to preserve original content. The probe points are kept in an rbtree. If user-space executes the probed inode:offset instruction address then an event is generated which can be recovered from the regular perf event channels and mmap-ed ring-buffer. Multiple probes at the same address are supported, they create a dynamic callback list of event consumers. The basic model is further complicated by the XOL speedup: the original instruction that is probed is copied (in an architecture specific fashion) and executed out of line when the probe triggers. The XOL area is a single vma per process, with a fixed number of entries (which limits probe execution parallelism). The API: uprobes are installed/removed via /sys/kernel/debug/tracing/uprobe_events, the API is integrated to align with the kprobes interface as much as possible, but is separate to it. Injecting a probe point is privileged operation, which can be relaxed by setting perf_paranoid to -1. You can use multiple probes as well and mix them with kprobes and regular PMU events or tracepoints, when instrumenting a task." Fix up trivial conflicts in mm/memory.c due to previous cleanup of unmap_single_vma(). * 'perf-uprobes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) perf probe: Detect probe target when m/x options are absent perf probe: Provide perf interface for uprobes tracing: Fix kconfig warning due to a typo tracing: Provide trace events interface for uprobes tracing: Extract out common code for kprobes/uprobes trace events tracing: Modify is_delete, is_return from int to bool uprobes/core: Decrement uprobe count before the pages are unmapped uprobes/core: Make background page replacement logic account for rss_stat counters uprobes/core: Optimize probe hits with the help of a counter uprobes/core: Allocate XOL slots for uprobes use uprobes/core: Handle breakpoint and singlestep exceptions uprobes/core: Rename bkpt to swbp uprobes/core: Make order of function parameters consistent across functions uprobes/core: Make macro names consistent uprobes: Update copyright notices uprobes/core: Move insn to arch specific structure uprobes/core: Remove uprobe_opcode_sz uprobes/core: Make instruction tables volatile uprobes: Move to kernel/events/ uprobes/core: Clean up, refactor and improve the code ...
2012-05-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial updates from Jiri Kosina: "As usual, it's mostly typo fixes, redundant code elimination and some documentation updates." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (57 commits) edac, mips: don't change code that has been removed in edac/mips tree xtensa: Change mail addresses of Hannes Weiner and Oskar Schirmer lib: Change mail address of Oskar Schirmer net: Change mail address of Oskar Schirmer arm/m68k: Change mail address of Sebastian Hess i2c: Change mail address of Oskar Schirmer net: Fix tcp_build_and_update_options comment in struct tcp_sock atomic64_32.h: fix parameter naming mismatch Kconfig: replace "--- help ---" with "---help---" c2port: fix bogus Kconfig "default no" edac: Fix spelling errors. qla1280: Remove redundant NULL check before release_firmware() call remoteproc: remove redundant NULL check before release_firmware() qla2xxx: Remove redundant NULL check before release_firmware() call. aic94xx: Get rid of redundant NULL check before release_firmware() call tehuti: delete redundant NULL check before release_firmware() qlogic: get rid of a redundant test for NULL before call to release_firmware() bna: remove redundant NULL test before release_firmware() tg3: remove redundant NULL test before release_firmware() call typhoon: get rid of redundant conditional before all to release_firmware() ...
2012-05-16ftrace: Remove selecting FRAME_POINTER with FUNCTION_TRACERSteven Rostedt
The function tracer will enable the -pg option with gcc, which requires that frame pointers. When FRAME_POINTER is defined in the kernel config it adds the gcc option -fno-omit-frame-pointer which causes some problems on some architectures. For those architectures, the FRAME_POINTER select was not set. When FUNCTION_TRACER was selected on these architectures that can not have -fno-omit-frame-pointer, the -pg option is still set. But when FRAME_POINTER is not selected, the kernel config would add the gcc option -fomit-frame-pointer. Adding this option is incompatible with -pg even on archs that do not need frame pointers with -pg. The answer to this was to just not add either -fno-omit-frame-pointer or -fomit-frame-pointer on these archs that want function tracing but do not set FRAME_POINTER. As it turns out, for archs that require frame pointers for function tracing, the same can be used. If gcc requires frame pointers with -pg, it will simply add it. The best thing to do is not select FRAME_POINTER when function tracing is selected, and let gcc add it if needed. Only add the -fno-omit-frame-pointer when something else selects FRAME_POINTER, but do not add -fomit-frame-pointer if function tracing is selected. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-05-07tracing: Provide trace events interface for uprobesSrikar Dronamraju
Implements trace_event support for uprobes. In its current form it can be used to put probes at a specified offset in a file and dump the required registers when the code flow reaches the probed address. The following example shows how to dump the instruction pointer and %ax a register at the probed text address. Here we are trying to probe zfree in /bin/zsh: # cd /sys/kernel/debug/tracing/ # cat /proc/`pgrep zsh`/maps | grep /bin/zsh | grep r-xp 00400000-0048a000 r-xp 00000000 08:03 130904 /bin/zsh # objdump -T /bin/zsh | grep -w zfree 0000000000446420 g DF .text 0000000000000012 Base zfree # echo 'p /bin/zsh:0x46420 %ip %ax' > uprobe_events # cat uprobe_events p:uprobes/p_zsh_0x46420 /bin/zsh:0x0000000000046420 # echo 1 > events/uprobes/enable # sleep 20 # echo 0 > events/uprobes/enable # cat trace # tracer: nop # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | zsh-24842 [006] 258544.995456: p_zsh_0x46420: (0x446420) arg1=446421 arg2=79 zsh-24842 [007] 258545.000270: p_zsh_0x46420: (0x446420) arg1=446421 arg2=79 zsh-24842 [002] 258545.043929: p_zsh_0x46420: (0x446420) arg1=446421 arg2=79 zsh-24842 [004] 258547.046129: p_zsh_0x46420: (0x446420) arg1=446421 arg2=79 Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com> Cc: Linux-mm <linux-mm@kvack.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Anton Arapov <anton@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120411103043.GB29437@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-07tracing: Extract out common code for kprobes/uprobes trace eventsSrikar Dronamraju
Move parts of trace_kprobe.c that can be shared with upcoming trace_uprobe.c. Common code to kernel/trace/trace_probe.h and kernel/trace/trace_probe.c. There are no functional changes. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com> Cc: Linux-mm <linux-mm@kvack.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Anton Arapov <anton@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120409091144.8343.76218.sendpatchset@srdronam.in.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-04-18Fix "the the" in various KconfigMasanari Iida
Fix typo "the the" in various Kconfig. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-02-27tracing: Do not select FRAME_POINTER on PPCGerlando Falauto
On PowerPC, FUNCTION_TRACER selects FRAME_POINTER, even though the architecture does not support it. This causes the following warning: warning: (LOCKDEP && FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && FUNCTION_TRACER && KMEMCHECK) selects FRAME_POINTER which has unmet direct dependencies (DEBUG_KERNEL && (CRIS || M68K || FRV || UML || AVR32 || SUPERH || BLACKFIN || MN10300) || ARCH_WANT_FRAME_POINTERS) So remove the warning by adding the extra condition "if !PPC" to FUNCTION_TRACER for FRAME_POINTER selection Link: http://lkml.kernel.org/r/1330330101-8618-1-git-send-email-gerlando.falauto@keymile.com Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-07-25trace events: Update version number reference to new 3.x scheme for ↵Jesper Juhl
EVENT_POWER_TRACING_DEPRECATED What was scheduled to be 2.6.41 is now going to be 3.1 . Signed-off-by: Jesper Juhl <jj@chaosbits.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1107250929370.8080@swampdragon.chaosbits.net Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-21ftrace: Build without frame pointers on MicroblazeMichal Simek
Microblaze doesn't need/support FRAME_POINTERS in order to have a working function tracer. The patch remove Kconfig warning. Warning log: warning: (LOCKDEP && FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && FUNCTION_TRACER && KMEMCHECK) selects FRAME_POINTER which has unmet direct dependencies (DEBUG_KERNEL && (CRIS || M68K || FRV || UML || AVR32 || SUPERH || BLACKFIN || MN10300) || ARCH_WANT_FRAME_POINTERS) Signed-off-by: Michal Simek <monstr@monstr.eu> Link: http://lkml.kernel.org/r/1301908812-8119-2-git-send-email-monstr@monstr.eu CC: Frederic Weisbecker <fweisbec@gmail.com> CC: Ingo Molnar <mingo@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-03-17trace, documentation: Fix branch profiling location in debugfsDavid Rientjes
The debugfs interface for branch profiling is through /sys/kernel/debug/tracing/trace_stat/branch_annotated /sys/kernel/debug/tracing/trace_stat/branch_all so update the Kconfig accordingly. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <alpine.DEB.2.00.1103161716320.11407@chino.kir.corp.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-04perf: Clean up power events by introducing new, more generic onesThomas Renninger
Add these new power trace events: power:cpu_idle power:cpu_frequency power:machine_suspend The old C-state/idle accounting events: power:power_start power:power_end Have now a replacement (but we are still keeping the old tracepoints for compatibility): power:cpu_idle and power:power_frequency is replaced with: power:cpu_frequency power:machine_suspend is newly introduced. Jean Pihet has a patch integrated into the generic layer (kernel/power/suspend.c) which will make use of it. the type= field got removed from both, it was never used and the type is differed by the event type itself. perf timechart userspace tool gets adjusted in a separate patch. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Jean Pihet <jean.pihet@newoldbits.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: rjw@sisk.pl LKML-Reference: <1294073445-14812-3-git-send-email-trenn@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1290072314-31155-2-git-send-email-trenn@suse.de>
2010-11-10[S390] ftrace: build without frame pointers on s390Heiko Carstens
s390 doesn't need FRAME_POINTERS in order to have a working function tracer. We don't need frame pointers in order to get strack traces since we always have valid backchains by using the -mkernel-backchain gcc option. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-21Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (278 commits) arm: remove machine_desc.io_pg_offst and .phys_io arm: use addruart macro to establish debug mappings arm: return both physical and virtual addresses from addruart arm/debug: consolidate addruart macros for CONFIG_DEBUG_ICEDCC ARM: make struct machine_desc definition coherent with its comment eukrea_mbimxsd-baseboard: Pass the correct GPIO to gpio_free cpuimx27: fix compile when ULPI is selected mach-pcm037_eet: fix compile errors Fixing ethernet driver compilation error for i.MX31 ADS board cpuimx51: update board support mx5: add cpuimx51sd module and its baseboard iomux-mx51: fix GPIO_1_xx 's IOMUX configuration imx-esdhc: update devices registration mx51: add resources for SD/MMC on i.MX51 iomux-mx51: fix SD1 and SD2's iomux configuration clock-mx51: rename CLOCK1 to CLOCK_CCGR for better readability clock-mx51: factorize clk_set_parent and clk_get_rate eukrea_mbimxsd: add support for DVI displays cpuimx25 & cpuimx35: fix OTG port registration in host mode i.MX31 and i.MX35 : fix errate TLSbo65953 and ENGcm09472 ...
2010-10-14ftrace: Rename config option HAVE_C_MCOUNT_RECORD to HAVE_C_RECORDMCOUNTSteven Rostedt
The config option used by archs to let the build system know that the C version of the recordmcount works for said arch is currently called HAVE_C_MCOUNT_RECORD which enables BUILD_C_RECORDMCOUNT. To be more consistent with the name that all archs may use, it has been renamed to HAVE_C_RECORDMCOUNT. This will be less confusing since we are building a C recordmcount and not a mcount_record. Suggested-by: Ingo Molnar <mingo@elte.hu> Cc: <linux-arch@vger.kernel.org> Cc: Michal Marek <mmarek@suse.cz> Cc: linux-kbuild@vger.kernel.org Cc: John Reiser <jreiser@bitwagon.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-10-14ftrace/x86: Add support for C version of recordmcountSteven Rostedt
This patch adds the support for the C version of recordmcount and compile times show ~ 12% improvement. After verifying this works, other archs can add: HAVE_C_MCOUNT_RECORD in its Kconfig and it will use the C version of recordmcount instead of the perl version. Cc: <linux-arch@vger.kernel.org> Cc: Michal Marek <mmarek@suse.cz> Cc: linux-kbuild@vger.kernel.org Cc: John Reiser <jreiser@bitwagon.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-02ARM: 6314/1: ftrace: allow build without frame pointers on ARMRabin Vincent
With a new enough GCC, ARM function tracing can be supported without the need for frame pointers. This is essential for Thumb-2 support, since frame pointers aren't available then. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-08-07Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (55 commits) workqueue: mark init_workqueues() as early_initcall() workqueue: explain for_each_*cwq_cpu() iterators fscache: fix build on !CONFIG_SYSCTL slow-work: kill it gfs2: use workqueue instead of slow-work drm: use workqueue instead of slow-work cifs: use workqueue instead of slow-work fscache: drop references to slow-work fscache: convert operation to use workqueue instead of slow-work fscache: convert object to use workqueue instead of slow-work workqueue: fix how cpu number is stored in work->data workqueue: fix mayday_mask handling on UP workqueue: fix build problem on !CONFIG_SMP workqueue: fix locking in retry path of maybe_create_worker() async: use workqueue for worker pool workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead workqueue: implement unbound workqueue workqueue: prepare for WQ_UNBOUND implementation libata: take advantage of cmwq and remove concurrency limitations workqueue: fix worker management invocation without pending works ... Fixed up conflicts in fs/cifs/* as per Tejun. Other trivial conflicts in include/linux/workqueue.h, kernel/trace/Kconfig and kernel/workqueue.c
2010-08-06Merge branch 'timers-timekeeping-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-timekeeping-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: um: Fix read_persistent_clock fallout kgdb: Do not access xtime directly powerpc: Clean up obsolete code relating to decrementer and timebase powerpc: Rework VDSO gettimeofday to prevent time going backwards clocksource: Add __clocksource_updatefreq_hz/khz methods x86: Convert common clocksources to use clocksource_register_hz/khz timekeeping: Make xtime and wall_to_monotonic static hrtimer: Cleanup direct access to wall_to_monotonic um: Convert to use read_persistent_clock timkeeping: Fix update_vsyscall to provide wall_to_monotonic offset powerpc: Cleanup xtime usage powerpc: Simplify update_vsyscall time: Kill off CONFIG_GENERIC_TIME time: Implement timespec_add x86: Fix vtime/file timestamp inconsistencies Trivial conflicts in Documentation/feature-removal-schedule.txt Much less trivial conflicts in arch/powerpc/kernel/time.c resolved as per Thomas' earlier merge commit 47916be4e28c ("Merge branch 'powerpc.cherry-picks' into timers/clocksource")
2010-07-27time: Kill off CONFIG_GENERIC_TIMEJohn Stultz
Now that all arches have been converted over to use generic time via clocksources or arch_gettimeoffset(), we can remove the GENERIC_TIME config option and simplify the generic code. Signed-off-by: John Stultz <johnstul@us.ibm.com> LKML-Reference: <1279068988-21864-4-git-send-email-johnstul@us.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-07-20tracing: Remove sysprof ftrace pluginFrederic Weisbecker
The sysprof ftrace plugin doesn't seem to be seriously used somewhere. There is a branch in the sysprof tree that makes an interface to it, but the real sysprof tool uses either its own module or perf events. Drop the sysprof ftrace plugin then, as it's mostly useless. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Soeren Sandmann <sandmann@daimi.au.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Li Zefan <lizf@cn.fujitsu.com>
2010-07-15tracing: Remove ksym tracerFrederic Weisbecker
The ksym (breakpoint) ftrace plugin has been superseded by perf tools that are much more poweful to use the cpu breakpoints. This tracer doesn't bring more feature. It has been deprecated for a while now, lets remove it. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@elte.hu>
2010-06-29workqueue: temporarily remove workqueue tracingTejun Heo
Strip tracing code from workqueue and remove workqueue tracing. This is temporary measure till concurrency managed workqueue is complete. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com>
2010-06-09tracing: Remove kmemtrace ftrace pluginLi Zefan
We have been resisting new ftrace plugins and removing existing ones, and kmemtrace has been superseded by kmem trace events and perf-kmem, so we remove it. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> [ remove kmemtrace from the makefile, handle slob too ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-06-08tracing: Remove boot tracerAmérico Wang
The boot tracer is useless. It simply logs the initcalls but in fact these initcalls are also logged through printk while using the initcall_debug kernel parameter. Nobody seem to be using it so far. Then just remove it. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Chase Douglas <chase.douglas@canonical.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <20100526105753.GA5677@cr0.nay.redhat.com> [ remove the hooks in main.c, and the headers ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-03-26x86, perf, bts, mm: Delete the never used BTS-ptrace codePeter Zijlstra
Support for the PMU's BTS features has been upstreamed in v2.6.32, but we still have the old and disabled ptrace-BTS, as Linus noticed it not so long ago. It's buggy: TIF_DEBUGCTLMSR is trampling all over that MSR without regard for other uses (perf) and doesn't provide the flexibility needed for perf either. Its users are ptrace-block-step and ptrace-bts, since ptrace-bts was never used and ptrace-block-step can be implemented using a much simpler approach. So axe all 3000 lines of it. That includes the *locked_memory*() APIs in mm/mlock.c as well. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Markus Metzger <markus.t.metzger@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <20100325135413.938004390@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-27Merge branch 'tracing/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core
2010-02-26Merge branch 'tip/tracing/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/core
2010-02-25tracing: Remove CONFIG_TRACE_POWER from kernel configLi Zefan
The power tracer has been converted to power trace events. Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4B84D50E.4070806@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-02-17tracing/kprobes: Make Kconfig dependencies genericHeiko Carstens
KPROBES_EVENT actually depends on the regs and stack access API (b1cf540f) and not on x86. So introduce a new config option which architectures can select if they have the API implemented and switch x86. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> LKML-Reference: <20100210162517.GB6933@osiris.boeblingen.de.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-01-26tracing/documentation: Cover new frame pointer semanticsMike Frysinger
Update the graph tracer examples to cover the new frame pointer semantics (in terms of passing it along). Move the HAVE_FUNCTION_GRAPH_FP_TEST docs out of the Kconfig, into the right place, and expand on the details. Signed-off-by: Mike Frysinger <vapier@gentoo.org> LKML-Reference: <1264165967-18938-1-git-send-email-vapier@gentoo.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-12-28tracing: Kconfig spelling fixes and cleanupsRandy Dunlap
Fix filename reference (ftrace-implementation.txt -> ftrace-design.txt). Fix spelling, punctuation, grammar. Fix help text indentation and line lengths to reduce need for horizontal scrolling or larger window sizes. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091221120117.3fb49cdc.randy.dunlap@oracle.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21Merge branch 'tracing/hw-breakpoints' into perf/coreIngo Molnar
Conflicts: arch/x86/kernel/kprobes.c kernel/trace/Makefile Merge reason: hw-breakpoints perf integration is looking good in testing and in reviews, plus conflicts are mounting up - so merge & resolve. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-04tracing/kprobes: Rename Kprobe-tracer to kprobe-eventMasami Hiramatsu
Rename Kprobes-based event tracer to kprobes-based tracing event (kprobe-event), since it is not a tracer but an extensible tracing event interface. This also changes CONFIG_KPROBE_TRACER to CONFIG_KPROBE_EVENT and sets it y by default. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> LKML-Reference: <20091104001247.3454.14131.stgit@harusame> Signed-off-by: Ingo Molnar <mingo@elte.hu>