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* perf report: Enable TUI in branch view modeStephane Eranian2012-03-09
| | | | | | | | | | | | | | | | | | | | This patch updates perf report to support TUI mode when the perf.data file contains samples with branch stacks. For each row in the report, it is possible to annotate either the source or target of each branch. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: peterz@infradead.org Cc: acme@redhat.com Cc: asharma@fb.com Cc: ravitillo@lbl.gov Cc: vweaver1@eecs.utk.edu Cc: khandual@linux.vnet.ibm.com Cc: dsahern@gmail.com Link: http://lkml.kernel.org/r/1331246868-19905-5-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf tools: Add code to support PERF_SAMPLE_BRANCH_STACKRoberto Agostino Vitillo2012-03-09
| | | | | | | | | | | | | | | | | | | | | | This patch adds: - ability to parse samples with PERF_SAMPLE_BRANCH_STACK - sort on branches (dso_from, symbol_from, dso_to, symbol_to, mispredict) - build histograms on branches Signed-off-by: Roberto Agostino Vitillo <ravitillo@lbl.gov> Signed-off-by: Stephane Eranian <eranian@google.com> Cc: peterz@infradead.org Cc: acme@redhat.com Cc: robert.richter@amd.com Cc: ming.m.lin@intel.com Cc: andi@firstfloor.org Cc: asharma@fb.com Cc: vweaver1@eecs.utk.edu Cc: khandual@linux.vnet.ibm.com Cc: dsahern@gmail.com Link: http://lkml.kernel.org/r/1328826068-11713-12-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf script: Add option resolving vmlinux pathAkihiro Nagai2012-01-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the option get the path of [kernel.kallsyms]. Specify '--show-kernel-path' option to use this function. This patch enables other applications to use this output easily. Without --show-kernel-path option ffffffff81467612 irq_return ([kernel.kallsyms]) ffffffff81467612 irq_return ([kernel.kallsyms]) 7f24fc02a6b3 _start (/lib64/ld-2.14.so) [snip] With --show-kernel-path option ffffffff81467612 irq_return (/lib/modules/3.2.0+/build/vmlinux) ffffffff81467612 irq_return (/lib/modules/3.2.0+/build/vmlinux) 7f24fc02a6b3 _start (/lib64/ld-2.14.so) [snip] Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: yrl.pp-manager.tt@hitachi.com Link: http://lkml.kernel.org/r/20120130044320.2384.73322.stgit@linux3 Signed-off-by: Akihiro Nagai <akihiro.nagai.hw@hitachi.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf script: Add the offset field specifierAkihiro Nagai2012-01-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the offset field specifier 'symoff' to show the offset from the symbols in the output of perf-script. We can get the more detailed address information. Output sample: ffffffff81467612 irq_return+0x0 => 301ec016b0 _start+0x0 ffffffff81467612 irq_return+0x0 => 301ec016b0 _start+0x0 301ec016b3 _start+0x3 => 301ec04b70 _dl_start+0x0 ffffffff81467612 irq_return+0x0 => 301ec04b70 _dl_start+0x0 ffffffff81467612 irq_return+0x0 => 301ec04b96 _dl_start+0x26 ffffffff81467612 irq_return+0x0 => 301ec04b9d _dl_start+0x2d 301ec04beb _dl_start+0x7b => 301ec04c0d _dl_start+0x9d 301ec04c11 _dl_start+0xa1 => 301ec04bf0 _dl_start+0x80 [snip] Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: yrl.pp-manager.tt@hitachi.com Link: http://lkml.kernel.org/r/20120130044314.2384.67094.stgit@linux3 Signed-off-by: Akihiro Nagai <akihiro.nagai.hw@hitachi.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf script: Unify the expressions indicating "unknown"Akihiro Nagai2012-01-30
| | | | | | | | | | | | | | | | | | The perf script command uses various expressions to indicate "unknown". It is unfriendly for user scripts to parse it. So, this patch unifies the expressions to "[unknown]". Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: yrl.pp-manager.tt@hitachi.com Link: http://lkml.kernel.org/r/20120130044257.2384.62905.stgit@linux3 Signed-off-by: Akihiro Nagai <akihiro.nagai.hw@hitachi.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Add nr_events to symbol_confArnaldo Carvalho de Melo2011-11-28
| | | | | | | | | | | | | | Since symbol__alloc_hists need it, to avoid passing it around in many functions have it in the symbol_conf struct. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-cwv8ysvpywzjq4v3xtbd4zwv@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf report: Add option to show total periodArnaldo Carvalho de Melo2011-10-07
| | | | | | | | | | | | | | Just like --show-nr-samples, to help in diagnosing problems in the tools. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-1lr7ejdjfvy2uwy2wkmatcpq@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf annotate: Make output more readableStephane Eranian2011-08-18
| | | | | | | | | | | | | | | | | | | | This patch adds two new options to perf annotate: - --no-asm-raw : Do not display raw instruction encodings - --no-source : Do not interleave source code with assembly code We believe those options make the output of annotate more readable. Systematically displaying source can make it hard to follow code and especially optimized code. Raw encodings are not useful in most cases. Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20110517153207.GA9834@quad Signed-off-by: Stephane Eranian <eranian@google.com> [committer note: Use the 'no-' option inverting logic] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf report: Use properly build_id kernel binariesJiri Olsa2011-08-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we bring the recorded perf data together with kernel binary from another machine using: on server A: perf archive on server B: tar xjvf perf.data.tar.bz2 -C ~/.debug the build_id kernel dso is not properly recognized during the "perf report" command on server B. The reason is, that build_id dsos are added during the session initialization, while the kernel maps are created during the sample event processing. The machine__create_kernel_maps functions ends up creating new dso object for kernel, but it does not check if we already have one added by build_id processing. Also the build_id reading ABI quirk added in commit: - commit b25114817a73bbd2b84ce9dba02ee1ef8989a947 perf build-id: Add quirk to deal with perf.data file format breakage populates the "struct build_id_event::pid" with 0, which is later interpreted as DEFAULT_GUEST_KERNEL_ID. This is not always correct, so it's better to guess the pid value based on the "struct build_id_event::header::misc" value. - Tested with data generated on x86 kernel version v2.6.34 and reported back on x86_64 current kernel. - Not tested for guest kernel case. Note the problem stays for PERF_RECORD_MMAP events recorded by perf that does not use proper pid (HOST_KERNEL_ID/DEFAULT_GUEST_KERNEL_ID). They are misinterpreted within the current perf code. Probably there's not much we can do about that. Cc: Avi Kivity <avi@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Link: http://lkml.kernel.org/r/20110601194346.GB1934@jolsa.brq.redhat.com Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Handle /proc/sys/kernel/kptr_restrictArnaldo Carvalho de Melo2011-05-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Perf uses /proc/modules to figure out where kernel modules are loaded. With the advent of kptr_restrict, non root users get zeroes for all module start addresses. So check if kptr_restrict is non zero and don't generate the syntethic PERF_RECORD_MMAP events for them. Warn the user about it in perf record and in perf report. In perf report the reference relocation symbol being zero means that kptr_restrict was set, thus /proc/kallsyms has only zeroed addresses, so don't use it to fixup symbol addresses when using a valid kallsyms (in the buildid cache) or vmlinux (in the vmlinux path) build-id located automatically or specified by the user. Provide an explanation about it in 'perf report' if kernel samples were taken, checking if a suitable vmlinux or kallsyms was found/specified. Restricted /proc/kallsyms don't go to the buildid cache anymore. Example: [acme@emilia ~]$ perf record -F 100000 sleep 1 WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted, check /proc/sys/kernel/kptr_restrict. Samples in kernel functions may not be resolved if a suitable vmlinux file is not found in the buildid cache or in the vmlinux path. Samples in kernel modules won't be resolved at all. If some relocation was applied (e.g. kexec) symbols may be misresolved even with a suitable vmlinux or kallsyms file. [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.005 MB perf.data (~231 samples) ] [acme@emilia ~]$ [acme@emilia ~]$ perf report --stdio Kernel address maps (/proc/{kallsyms,modules}) were restricted, check /proc/sys/kernel/kptr_restrict before running 'perf record'. If some relocation was applied (e.g. kexec) symbols may be misresolved. Samples in kernel modules can't be resolved as well. # Events: 13 cycles # # Overhead Command Shared Object Symbol # ........ ....... ................. ..................... # 20.24% sleep [kernel.kallsyms] [k] page_fault 20.04% sleep [kernel.kallsyms] [k] filemap_fault 19.78% sleep [kernel.kallsyms] [k] __lru_cache_add 19.69% sleep ld-2.12.so [.] memcpy 14.71% sleep [kernel.kallsyms] [k] dput 4.70% sleep [kernel.kallsyms] [k] flush_signal_handlers 0.73% sleep [kernel.kallsyms] [k] perf_event_comm 0.11% sleep [kernel.kallsyms] [k] native_write_msr_safe # # (For a higher level overview, try: perf report --sort comm,dso) # [acme@emilia ~]$ This is because it found a suitable vmlinux (build-id checked) in /lib/modules/2.6.39-rc7+/build/vmlinux (use -v in perf report to see the long file name). If we remove that file from the vmlinux path: [root@emilia ~]# mv /lib/modules/2.6.39-rc7+/build/vmlinux \ /lib/modules/2.6.39-rc7+/build/vmlinux.OFF [acme@emilia ~]$ perf report --stdio [kernel.kallsyms] with build id 57298cdbe0131f6871667ec0eaab4804dcf6f562 not found, continuing without symbols Kernel address maps (/proc/{kallsyms,modules}) were restricted, check /proc/sys/kernel/kptr_restrict before running 'perf record'. As no suitable kallsyms nor vmlinux was found, kernel samples can't be resolved. Samples in kernel modules can't be resolved as well. # Events: 13 cycles # # Overhead Command Shared Object Symbol # ........ ....... ................. ...... # 80.31% sleep [kernel.kallsyms] [k] 0xffffffff8103425a 19.69% sleep ld-2.12.so [.] memcpy # # (For a higher level overview, try: perf report --sort comm,dso) # [acme@emilia ~]$ Reported-by: Stephane Eranian <eranian@google.com> Suggested-by: David Miller <davem@davemloft.net> Cc: Dave Jones <davej@redhat.com> Cc: David Miller <davem@davemloft.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Kees Cook <kees.cook@canonical.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> Link: http://lkml.kernel.org/n/tip-mt512joaxxbhhp1odop04yit@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Give more useful names to 'self' parametersArnaldo Carvalho de Melo2011-04-19
| | | | | | | | | | | | | | | | One more installment on an area that is mostly dormant. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbol: Move sym_entry->skip to symbol->ignoreArnaldo Carvalho de Melo2011-03-11
| | | | | | | | | | | | | | | | | | | While going thru each of the sym_entry fields looking to reduce it to the set of entries needed when in an active symbols list, 'skip' should really be in symbol, as we set it when loading the symtab. And the space used by the basic symbol allocation remains the same as we had 5 bytes of padding. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Rename dso->origin to dso->symtab_typeArnaldo Carvalho de Melo2011-03-11
| | | | | | | | | | | | | | | And the DSO__ORIG_ enum to SYMTAB__, to clarify that this is about from where the symtab was obtained. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf hists: Remove needless global col lenght calcsArnaldo Carvalho de Melo2011-03-05
| | | | | | | | | | | | | | | | | | | | | | To support multiple events we need to do these calcs per 'struct hists' instance, and it turns out we already do that at: __hists__add_entry hists__inc_nr_entries hists__calc_col_len for all the unfiltered hist_entry instances we stash in the rb tree, so trow away the dead code. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* Merge commit 'v2.6.37-rc8' into perf/coreIngo Molnar2011-01-04
|\ | | | | | | | | | | Merge reason: pick up latest -rc. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf probe: Fix use of kernel image path given by 'k' optionFranck Bui-Huu2010-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Users were not being able to have the explicitely specified vmlinux pathname used, instead a search on the vmlinux path was always being made. Reported-by: Francis Moreau <francis.moro@gmail.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: 2nddept-manager@sdl.hitachi.co.jp Cc: Francis Moreau <francis.moro@gmail.com> Cc: Franck Bui-Huu <vagabon.xyz@gmail.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> LPU-Reference: <m3hbelydz8.fsf_-_@gmail.com> Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | perf symbols: Improve kallsyms symbol end addr calculationArnaldo Carvalho de Melo2010-12-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For kallsyms we don't have the symbol address end, so we do an extra pass and set the symbol end addr as being the start of the next minus one. But this was being done just after we filtered the symbols of a particular type (functions, variables), so the symbol end was sometimes after what it really is. Fixing up symbol end also was falling apart when we have symbol aliases, then the end address of all but the last alias was being set to be before its start. Fix it up by checking for symbol aliases and making the kallsyms__parse routine use the next symbol, whatever its type, as the limit for the previous symbol, passing that end address to the callback. This was detected by the 'perf test' synthetic paranoid regression tests, fix it up so that even that case doesn't mislead us. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephane Eranian <eranian@google.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | perf symbols: Add symfs option for off-box analysis using specified treeDavid Ahern2010-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The symfs argument allows analysis of perf.data file using a locally accessible filesystem tree with debug symbols - e.g., tree created during image builds, sshfs mount, loop mounted KVM disk images, USB keys, initrds, etc. Anything with an OS tree can be analyzed from anywhere without the need to populate a local data store with build-ids. Commiter notes: o Fixed up symfs="/" variants handling. o prefixed DSO__ORIG_GUEST_KMODULE case with symfs too, avoiding use of files outside the symfs directory. LKML-Reference: <1291926427-28846-1-git-send-email-daahern@cisco.com> Signed-off-by: David Ahern <daahern@cisco.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | perf report: Allow user to specify path to kallsyms fileDavid Ahern2010-12-09
|/ | | | | | | | | | | | This is useful for analyzing a perf data file on a different system than the one data was collected on and still include symbols from loaded kernel modules in the output. Commiter note: Updated the man page accordingly. LKML-Reference: <1291775986-16475-1-git-send-email-daahern@cisco.com> Signed-off-by: David Ahern <daahern@cisco.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* Merge branch 'tip/perf/core' of ↵Ingo Molnar2010-09-15
|\ | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core
| * perf symbols: Fix multiple initialization of symbol systemJovi Zhang2010-09-09
| | | | | | | | | | | | | | | | | | | | | | | | | | By returning immediately if it was already initialized, do it as well at symbol__exit, refusing multiple deinitializations. This fixes problems in the kmem, sched and timechart commands. Reported-by: Davidlohr Bueso <dave@gnu.org> Cc: Davidlohr Bueso <dave@gnu.org> Signed-off-by: Jovi Zhang <bookjovi@gmail.com> LKML-Reference: AANLkTi=9Cn=R8SPMCRp5z+gEjXbaBHeb-AaOtRbuwwcn@mail.gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | perf symbols: List symbols in a dso in ascending name orderSrikar Dronamraju2010-08-25
|/ | | | | | | | | | | | | | | | | | | | | | | | Given a dso, list the symbols in ascending name order. Needed for listing available symbols from perf probe. Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: "Frank Ch. Eigler" <fche@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com> Cc: Mark Wielaard <mjw@redhat.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Naren A Devaiah <naren.devaiah@in.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <20100825134329.5447.92261.sendpatchset@localhost6.localdomain6> Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Store the symbol bindingArnaldo Carvalho de Melo2010-08-05
| | | | | | | | | | | | | | So that tools that wan't to act only on a subset of (weak, global, local) symbols can do so, such as the upcoming uprobes support in 'perf probe'. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Stephane Eranian <eranian@google.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf session: Free the ref_reloc_sym memory at the right placeArnaldo Carvalho de Melo2010-08-02
| | | | | | | | | | | | | | | | | | | | | | | | Which is at perf_session__destroy_kernel_maps, counterpart to the perf_session__create_kernel_maps where the kmap structure is located, just after the vmlinux_maps. Make it also check if the kernel maps were actually created, which may not be the case if, for instance, perf_session__new can't complete due to permission problems in, for instance, a 'perf report' case, when a segfault will take place, that is how this was noticed. The problem was introduced in d65a458, thus post .35. This also adds code to release guest machines as them are also created in perf_session__create_kernel_maps, so should be deleted on this newly introduced counterpart, perf_session__destroy_kernel_maps. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Release session and symbol resources on exitArnaldo Carvalho de Melo2010-07-30
| | | | | | | | | | | | So that we reduce the noise when looking for leaks using tools such as valgrind. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Precisely specify if dso->{long,short}_name should be freedArnaldo Carvalho de Melo2010-07-29
| | | | | | | | | Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Remove unneeded code for tracking the cwd in perf sessionsDave Martin2010-07-27
| | | | | | | | | | Tidy-up patch to remove some code and struct perf_session data members which are no longer needed due to the previous patch: "perf tools: Don't abbreviate file paths relative to the cwd". LKML-Reference: <new-submission> Signed-off-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf ui: New hists tree widgetArnaldo Carvalho de Melo2010-07-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The stock newt checkbox tree widget we were using was not really suitable for hist entry + callchain browsing. The problems with it were manifold: - We needed to traverse the whole hist_entry rb_tree to add each entry + callchains beforehand. - No control over the colors used for each row So a new tree widget, based mostly on slang, was written. It extends the ui_browser class already used for annotate to allow the user to fold/unfold branches in the callchains tree, using extra fields in the symbol_map class that is embedded in hist_entry and callchain_node instances to store the folding state and when changing this state calculates the number of rows that are produced when showing a particular hist_entry instance. This greatly speeds up browsing as we don't have to upfront touch all the entries and only calculate callchain related operations when some callchain branch is actually unfolded. The memory footprint is also reduced as the data structure is not duplicated, just some extra fields for controling callchain state and to simplify the process of seeking thru entries (nr_rows, row_offset) were added. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf sort: Make column width code per hists instanceArnaldo Carvalho de Melo2010-07-23
| | | | | | | | | | | | | They were globals, and since we support multiple hists and sessions at the same time, it doesn't make sense to calculate those values considereing all symbols in all sessions. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf probe: Add kernel source path optionChase Douglas2010-06-17
| | | | | | | | | | | | | | | | The probe plugin requires access to the source code for some operations. The source code must be in the exact same location as specified by the DWARF tags, but sometimes the location is an absolute path that cannot be replicated by a normal user. This change adds the -s|--source option to allow the user to specify the root of the kernel source tree. Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Masami Hiramatsu <mhiramat@redhat.com> LKML-Reference: <1276543590-10486-1-git-send-email-chase.douglas@canonical.com> Signed-off-by: Chase Douglas <chase.douglas@canonical.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf report: Implement --sort cpuArun Sharma2010-06-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In a shared multi-core environment, users want to analyze why their program was slow. In particular, if the code ran slower only on certain CPUs due to interference from other programs or kernel threads, the user should be able to notice that. Sample usage: perf record -f -a -- sleep 3 perf report --sort cpu,comm Workload: program is running on 16 CPUs Experiencing interference from an antagonist only on 4 CPUs. Samples: 106218177676 cycles Overhead CPU Command ........ ... ............... 6.25% 2 program 6.24% 6 program 6.24% 11 program 6.24% 5 program 6.24% 9 program 6.24% 10 program 6.23% 15 program 6.23% 7 program 6.23% 3 program 6.23% 14 program 6.22% 1 program 6.20% 13 program 3.17% 12 program 3.15% 8 program 3.14% 0 program 3.13% 4 program 3.11% 4 antagonist 3.11% 0 antagonist 3.10% 8 antagonist 3.07% 12 antagonist Cc: David S. Miller <davem@davemloft.net> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <20100505181612.GA5091@sharma-home.net> Signed-off-by: Arun Sharma <aruns@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf buildid: add perfconfig option to specify buildid cache dirStephane Eranian2010-06-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the ability to specify an alternate directory to store the buildid cache (buildids, copy of binaries). By default, it is hardcoded to $HOME/.debug. This directory contains immutable data. The layout of the directory is such that no conflicts in filenames are possible. A modification in a file, yields a different buildid and thus a different location in the subdir hierarchy. You may want to put the buildid cache elsewhere because of disk space limitation or simply to share the cache between users. It is also useful for remote collect vs. local analysis of profiles. This patch adds a new config option to the perfconfig file. Under the tag 'buildid', there is a dir option. For instance, if you have: $ cat /etc/perfconfig [buildid] dir = /var/cache/perf-buildid All buildids and binaries are be saved in the directory specified. The perf record, buildid-list, buildid-cache, report, annotate, and archive commands will it to pull information out. The option can be set in the system-wide perfconfig file or in the $HOME/.perfconfig file. Cc: David S. Miller <davem@davemloft.net> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <4c055fb7.df0ce30a.5f0d.ffffae52@mx.google.com> Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Add the build id cache to the vmlinux pathArnaldo Carvalho de Melo2010-05-26
| | | | | | | | | | | | | | | | | | | | So that if the kernel DSO has a build id because record inserted it in the perf.data build id table in the header, or a BUILD_ID event was inserted in the stream, we first look at the build id cache ($HOME/.debug/). If we find it there, try to use it, allowing offline annotation in addition to 'perf report'. Reported-by: Stephane Eranian <eranian@google.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf session: Make read_build_id routines look at the host_machine tooArnaldo Carvalho de Melo2010-05-19
| | | | | | | | | | | | | | | | | | | | | The changes made to support host and guest machines in a session, that started when the 'perf kvm' tool was introduced ended up introducing a bug where the host_machine was not having its DSOs traversed for build-id processing. Fix it by moving some methods to the right classes and considering the host_machine when processing build-ids. Reported-by: Tom Zanussi <tzanussi@gmail.com> Reported-by: Stephane Eranian <eranian@google.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf options: Type check all the remaining OPT_ variantsArnaldo Carvalho de Melo2010-05-17
| | | | | | | | | | | | | | | | | | OPT_SET_INT was renamed to OPT_SET_UINT since the only use in these tools is to set something that has an enum type, that is builtin compatible with unsigned int. Several string constifications were done to make OPT_STRING require a const char * type. Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf hist: Calculate max_sym name len and nr_entriesArnaldo Carvalho de Melo2010-05-10
| | | | | | | | | | | | | Better done when we are adding entries, be it initially of when we're re-sorting the histograms. Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf session: Embed the host machine data on perf_sessionArnaldo Carvalho de Melo2010-05-09
| | | | | | | | | | | | | | | | | | | | | | We have just one host on a given session, and that is the most common setup right now, so embed a ->host_machine struct machine instance directly in the perf_session class, check if we're looking for it before going to the rb_tree. This also fixes a problem found when we try to process old perf.data files where we didn't have MMAP events for the kernel and modules and thus don't create the kernel maps, do it in event__preprocess_sample if it wasn't already. Reported-by: Ingo Molnar <mingo@elte.hu> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Zhang, Yanmin <yanmin_zhang@linux.intel.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf symbols: Add machine helper routinesArnaldo Carvalho de Melo2010-04-29
| | | | | | | | | | | Created when writing the first 'perf test' regression testing routine. Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf machines: Make the machines class adopt the dsos__fprintf methodsArnaldo Carvalho de Melo2010-04-27
| | | | | | | | | | | | | | Now those methods don't operate on a global list of dsos, but on lists of machines, so make this clear by renaming the functions. Cc: Avi Kivity <avi@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zhang, Yanmin <yanmin_zhang@linux.intel.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf machine: Adopt some map_groups functionsArnaldo Carvalho de Melo2010-04-27
| | | | | | | | | | | | | | | | | | Those functions operated on members now grouped in 'struct machine', so move those methods to this new class. The changes made to 'perf probe' shows that using this abstraction inserting probes on guests almost got supported for free. Cc: Avi Kivity <avi@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zhang, Yanmin <yanmin_zhang@linux.intel.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Rename "kernel_info" to "machine"Arnaldo Carvalho de Melo2010-04-27
| | | | | | | | | | | | | | | | | | struct kernel_info and kerninfo__ are too vague, what they really describe are machines, virtual ones or hosts. There are more changes to introduce helpers to shorten function calls and to make more clear what is really being done, but I left that for subsequent patches. Cc: Avi Kivity <avi@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Zhang, Yanmin <yanmin_zhang@linux.intel.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf: 'perf kvm' tool for monitoring guest performance from hostZhang, Yanmin2010-04-19
| | | | | | | Here is the patch of userspace perf tool. Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* perf symbols: Move hex2u64 and strxfrchar to symbol.cArnaldo Carvalho de Melo2010-03-26
| | | | | | | | | | | | | | | Mostly used in symbol.c so move them there to reduce the number of files needed to use the symbol system. Also do some header adjustments with the same intent. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1269557941-15617-5-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf tools: Introduce struct map_symbolArnaldo Carvalho de Melo2010-03-26
| | | | | | | | | | | | | | | | That will be in both struct hist_entry and struct callchain_list, so that the TUI can store a pointer to the pair (map, symbol) in the trees where hist_entries and callchain_lists are present, to allow precise annotation instead of looking for the first symbol with the selected name. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1269459619-982-4-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'perf/urgent' into perf/coreIngo Molnar2010-03-17
|\ | | | | | | | | | | Merge reason: We'll be queueing dependent changes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf top: Improve the autosizing of column lenghtsArnaldo Carvalho de Melo2010-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When profiling C++ workloads the symbol name length can be really big, so cap it before it garbles the result. This builds upon the autosizing already present where we choose to use the short, basename of DSOs instead of its long, full pathname. Reported-by: Pavel Krauz <krauz@cngroup.cz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1268676230-9261-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf annotate: Properly notify the user that vmlinux is missingArnaldo Carvalho de Melo2010-03-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this patch we would not find a vmlinux, then try to pass objdump "[kernel.kallsyms]" as the filename, it would get confused and produce no output: [root@doppio ~]# perf annotate n_tty_write ------------------------------------------------ Percent | Source code & Disassembly of [kernel.kallsyms] ------------------------------------------------ Now we check that and emit meaningful warning: [root@doppio ~]# perf annotate n_tty_write Can't annotate n_tty_write: No vmlinux file was found in the path: [0] vmlinux [1] /boot/vmlinux [2] /boot/vmlinux-2.6.34-rc1-tip+ [3] /lib/modules/2.6.34-rc1-tip+/build/vmlinux [4] /usr/lib/debug/lib/modules/2.6.34-rc1-tip+/vmlinux [root@doppio ~]# This bug was introduced when we added automatic search for vmlinux, before that time the user had to specify a vmlinux file. v2: Print the warning just for the first symbol found when no symbol name is specified, otherwise it will spam the screen repeating the warning for each symbol. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: <stable@kernel.org> LKML-Reference: <1268669073-6856-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf top: Properly notify the user that vmlinux is missingArnaldo Carvalho de Melo2010-03-15
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this patch this message would very briefly appear on the screen and then the screen would get updates only on the top, for number of interrupts received, etc, but no annotation would be performed: [root@doppio linux-2.6-tip]# perf top -s n_tty_write > /tmp/bla objdump: '[kernel.kallsyms]': No such file Now this is what the user gets: [root@doppio linux-2.6-tip]# perf top -s n_tty_write Can't annotate n_tty_write: No vmlinux file was found in the path: [0] vmlinux [1] /boot/vmlinux [2] /boot/vmlinux-2.6.33-rc5 [3] /lib/modules/2.6.33-rc5/build/vmlinux [4] /usr/lib/debug/lib/modules/2.6.33-rc5/vmlinux [root@doppio linux-2.6-tip]# This bug was introduced when we added automatic search for vmlinux, before that time the user had to specify a vmlinux file. Reported-by: David S. Miller <davem@davemloft.net> Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: <stable@kernel.org> LKML-Reference: <1268664418-28328-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf annotate: Defer allocating sym_priv->hist arrayArnaldo Carvalho de Melo2010-02-25
| | | | | | | | | | | | | | | | | | | Because symbol->end is not fixed up at symbol_filter time, only after all symbols for a DSO are loaded, and that, for asm symbols, may be bogus, causing segfaults when hits happen in these symbols. Reported-by: David Miller <davem@davemloft.net> Reported-by: Anton Blanchard <anton@samba.org> Acked-by: David Miller <davem@davemloft.net> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: <stable@kernel.org> # for .33.x. Does not apply cleanly, needs backport. LKML-Reference: <20100225155740.GB8553@ghostprotocols.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf record: Stop intercepting events, use postprocessing to get build-idsArnaldo Carvalho de Melo2010-02-04
| | | | | | | | | | | | | | | | | | | We want to stream events as fast as possible to perf.data, and also in the future we want to have splice working, when no interception will be possible. Using build_id__mark_dso_hit_ops to create the list of DSOs that back MMAPs we also optimize disk usage in the build-id cache by only caching DSOs that had hits. Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1265223128-11786-6-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>