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* perf symbols: Add support for 'variable' symtabsArnaldo Carvalho de Melo2009-12-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Example: { u64 addr = strtoull(sym_filter, NULL, 16); struct map *map = map_groups__find(kmaps, MAP__VARIABLE, addr); if (map == NULL) pr_err("couldn't find map!\n"); else { struct symbol *sym = map__find_symbol(map, addr, NULL); if (sym == NULL) pr_err("couldn't find addr!\n"); else pr_info("addr %#Lx is in %s global var\n", addr, sym->name); } exit(0); } Added just after symbol__init() call in 'perf top', then: { u64 addr = strtoull(sym_filter, NULL, 16); struct map *map = map_groups__find(kmaps, MAP__VARIABLE, addr); if (map == NULL) pr_err("couldn't find map!\n"); else { struct symbol *sym = map__find_symbol(map, addr, NULL); if (sym == NULL) pr_err("couldn't find addr!\n"); else pr_info("addr %#Lx is in %s global var\n", addr, sym->name); } exit(0); } [root@doppio linux-2.6-tip]# grep ' [dD] ' /proc/kallsyms | grep ' sched' ffffffff817827d8 d sched_nr_latency ffffffff81782ce0 d sched_domains_mutex ffffffff8178c070 d schedstr.22423 ffffffff817909a0 d sched_register_mutex ffffffff81823490 d sched_feat_names ffffffff81823558 d scheduler_running ffffffff818235b8 d sched_clock_running ffffffff818235bc D sched_clock_stable ffffffff81824f00 d sched_switch_trace [root@doppio linux-2.6-tip]# perf top -s 0xffffffff817827d9 addr 0xffffffff817827d9 is in sched_nr_latency global var [root@doppio linux-2.6-tip]# perf top -s ffffffff81782ce0 addr 0xffffffff81782ce0 is in sched_domains_mutex global var [root@doppio linux-2.6-tip]# [root@doppio linux-2.6-tip]# perf top -s ffffffff81782ce0 --vmlinux OFF The file OFF cannot be used, trying to use /proc/kallsyms...addr 0xffffffff81782ce0 is in sched_domains_mutex global var [root@doppio linux-2.6-tip]# perf top -s ffffffff818235bc --vmlinux OFF The file OFF cannot be used, trying to use /proc/kallsyms...addr 0xffffffff818235bc is in sched_clock_stable global var [root@doppio linux-2.6-tip]# So it works with both /proc/kallsyms and with ELF symtabs, either the one on the vmlinux explicitely passed via --vmlinux or in one in the vmlinux_path that matches the buildid for the running kernel or the one found in the buildid header section in a perf.data file. 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: <1260550239-5372-4-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf symbols: Introduce ELF counterparts to symbol_type__is_aArnaldo Carvalho de Melo2009-12-12
| | | | | | | | | | | | For selecting the right types of symbols in ELF symtabs. 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: <1260550239-5372-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf symbols: Introduce symbol_type__is_aArnaldo Carvalho de Melo2009-12-12
| | | | | | | | | | | | | | For selecting the right types of symbols in /proc/kallsyms, will be followed by elf_symbol_type__is_a, for the same purpose on ELF symtabs. 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: <1260550239-5372-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf symbols: Rename kthreads to kmaps, using another abstraction for itArnaldo Carvalho de Melo2009-12-12
| | | | | | | | | | | | | | | | | | | | | | | | | | Using a struct thread instance just to hold the kernel space maps (vmlinux + modules) is overkill and confuses people trying to understand the perf symbols abstractions. The kernel maps are really present in all threads, i.e. the kernel is a library, not a separate thread. So introduce the 'map_groups' abstraction and use it for the kernel maps, now in the kmaps global variable. It, in turn, will move, together with the threads list to the perf_file abstraction, so that we can support multiple perf_file instances, needed by perf diff. Brainstormed-with: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Eduardo Habkost <ehabkost@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: <1260550239-5372-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf tools: Allow building for ARMJamie Iles2009-12-11
| | | | | | | | | | | | | | | | | Add definitions of rmb() and cpu_relax() and include the ARM unistd.h header. The __kuser_memory_barrier helper in the helper page is used to provide the correct memory barrier depending on the CPU type. [ The rmb() will work on v6 and v7, segfault on v5. Dynamic detection to add v5 support will be added later. ] Signed-off-by: Jamie Iles <jamie.iles@picochip.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mikael Pettersson <mikpe@it.uu.se> LKML-Reference: <1260534009-5394-1-git-send-email-jamie.iles@picochip.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* hw-breakpoints: Handle bad modify_user_hw_breakpoint off-case return valueFrederic Weisbecker2009-12-11
| | | | | | | | | | | | | | | | While converting modify_user_hw_breakpoint() return value, we forgot to handle the off-case. It's not returning a pointer anymore. This solves the build warning reported by Stephen Rothwell against linux-next. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Prasad <prasad@linux.vnet.ibm.com> LKML-Reference: <1260529122-6260-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Prasad <prasad@linux.vnet.ibm.com>
* perf tools: Allow cross compilingJamie Iles2009-12-11
| | | | | | | | | | | | | | For embedded platforms, we want to be able to build the perf tools on a build machine to run on a different arch. This patch allows $CROSS_COMPILE to set the cross compiler. Additionally, if NO_LIBPERL is set, then don't use perl include paths as they will be for the host arch. Signed-off-by: Jamie Iles <jamie.iles@picochip.com> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <1260523260-15694-2-git-send-email-jamie.iles@picochip.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing, slab: Fix no callsite ifndef CONFIG_KMEMTRACELi Zefan2009-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | For slab, if CONFIG_KMEMTRACE and CONFIG_DEBUG_SLAB are not set, __do_kmalloc() will not track callers: # ./perf record -f -a -R -e kmem:kmalloc ^C # ./perf trace ... perf-2204 [000] 147.376774: kmalloc: call_site=c0529d2d ... perf-2204 [000] 147.400997: kmalloc: call_site=c0529d2d ... Xorg-1461 [001] 147.405413: kmalloc: call_site=0 ... Xorg-1461 [001] 147.405609: kmalloc: call_site=0 ... konsole-1776 [001] 147.405786: kmalloc: call_site=0 ... Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: linux-mm@kvack.org <linux-mm@kvack.org> Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> LKML-Reference: <4B21F8AE.6020804@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing, slab: Define kmem_cache_alloc_notrace ifdef CONFIG_TRACINGLi Zefan2009-12-11
| | | | | | | | | | | | | | | | | Define kmem_trace_alloc_{,node}_notrace() if CONFIG_TRACING is enabled, otherwise perf-kmem will show wrong stats ifndef CONFIG_KMEM_TRACE, because a kmalloc() memory allocation may be traced by both trace_kmalloc() and trace_kmem_cache_alloc(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: linux-mm@kvack.org <linux-mm@kvack.org> Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> LKML-Reference: <4B21F89A.7000801@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86, perf events: Check if we have APIC enabledCyrill Gorcunov2009-12-10
| | | | | | | | | | | | | | | | | | | | | | | | | Ralf Hildebrandt reported this boot warning: | Running a vanilla 2.6.32 as Xen DomU, I'm getting: | | [ 0.000999] CPU: Physical Processor ID: 0 | [ 0.000999] CPU: Processor Core ID: 1 | [ 0.000999] Performance Events: AMD PMU driver. | [ 0.000999] ------------[ cut here ]------------ | [ 0.000999] WARNING: at arch/x86/kernel/apic/apic.c:249 native_apic_write_dummy So we need to check if APIC functionality is available, and not just in the P6 driver but elsewhere as well. Reported-by: Ralf Hildebrandt <Ralf.Hildebrandt@charite.de> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091210165634.GF5086@lenovo> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf_event: Fix variable initialization in other codepathsXiao Guangrong2009-12-10
| | | | | | | | | Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B20BAA6.7010609@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf kmem: Fix unused argument build warningIngo Molnar2009-12-10
| | | | | | | | | | | | | | Fix: builtin-kmem.c: In function 'parse_caller_opt': builtin-kmem.c:690: error: unused parameter 'arg' builtin-kmem.c: In function 'parse_alloc_opt': builtin-kmem.c:697: error: unused parameter 'arg' Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> LKML-Reference: <4B20A195.8030106@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf symbols: perf_header__read_build_ids() offset'n'size should be u64Arnaldo Carvalho de Melo2009-12-10
| | | | | | | | | | | | | | | | | | | | | | | | As off_t is a long, so breaking things on 32-bit land. Now buildids work on 32-bit land. [root@ana ~]# uname -a Linux ana.ghostprotocols.net 2.6.31.6-162.fc12.i686 #1 SMP Fri Dec 4 01:09:09 EST 2009 i686 i686 i386 GNU/Linux [root@ana ~]# perf buildid-list | tail -5 136ee6792ba2ae57870ecd87369f4ae3194d5b27 /lib/libreadline.so.6.0 d202dcb1ad48d140065783657d37ae3f2d9ab83f /usr/bin/gdb 0a56c0c00dcc2e9e581ae9997f31957c9c4671df /usr/lib/libdwarf.so.0.0 5f9e6ac95241cbb3227608e0ff2a2e0cbbe72439 /home/acme/bin/perf 925d19eccc2ddb1c9d74dd178a011426f1b124a8 /bin/sleep [root@ana ~]# 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: <1260396578-19116-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf symbols: dsos__read_build_ids() should read both user and kernel buildidsArnaldo Carvalho de Melo2009-12-10
| | | | | | | | | | 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: <1260396578-19116-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf tools: Align long options which have no short formsLi Zefan2009-12-10
| | | | | | | | | | | | | | | | | | | | | Before: $ ./perf kmem ... -l, --line <num> show n lines --raw-ip show raw ip instead of symbol After: $ ./perf kmem ... -l, --line <num> show n lines --raw-ip show raw ip instead of symbol Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> LKML-Reference: <4B20A1A9.3040104@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf kmem: Show usage if no option is specifiedLi Zefan2009-12-10
| | | | | | | | | | | As Ingo suggested, make "perf kmem" show help information. "perf kmem stat [--caller] [--alloc] .." will show memory statistics. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> LKML-Reference: <4B20A195.8030106@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: Mark sched_clock() as notraceMike Frysinger2009-12-10
| | | | | | | | | | | | The core ftrace code (trace_clock_local) calls sched_clock() directly, so we don't want to recurisvely trigger the ftrace code. Rather than update every sched_clock() definition, tag the prototype for everyone as notrace. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <1260407223-10900-1-git-send-email-vapier@gentoo.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf sched: Add max delay time snapshotFrederic Weisbecker2009-12-10
| | | | | | | | | | | | | | | | When we have a maximum latency reported for a task, we need a convenient way to find the matching location to the raw traces or to perf sched map that shows where the task has been eventually scheduled in. This gives a pointer to retrieve the events that occured during this max latency. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1260391208-6808-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf tools: Correct size given to memsetJulia Lawall2009-12-10
| | | | | | | | | | | | | | | | | | | | | | | | | | Memset should be given the size of the structure, not the size of the pointer. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ type T; T *x; expression E; @@ memset(x, E, sizeof( + * x)) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <Pine.LNX.4.64.0912092026000.1870@ask.diku.dk> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf_event: Fix perf_swevent_hrtimer() variable initializationXiao Guangrong2009-12-10
| | | | | | | | | | | | | | | | | | | | | | | | fix: [<c0477471>] ? printk+0x1d/0x24 [<c01c98f9>] ? perf_prepare_sample+0x269/0x280 [<c0149231>] warn_slowpath_common+0x71/0xd0 [<c01c98f9>] ? perf_prepare_sample+0x269/0x280 [<c01492aa>] warn_slowpath_null+0x1a/0x20 [<c01c98f9>] perf_prepare_sample+0x269/0x280 [<c016e9f3>] ? cpu_clock+0x53/0x90 [<c01cc368>] __perf_event_overflow+0x2a8/0x300 [<c01ccc3b>] perf_event_overflow+0x1b/0x30 [<c01ccccf>] perf_swevent_hrtimer+0x7f/0x120 This is because 'data.raw' variable not initialize. Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B208E93.1010801@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf sched: Fix for getting task's execution timeXiao Guangrong2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | In current code, task's execute time is got by reading '/proc/<pid>/sched' file, it's wrong if the task is created by pthread_create(), because every thread task has same pid. This way also has two demerits: 1: 'perf sched replay' can't work if the kernel is not compiled with the 'CONFIG_SCHED_DEBUG' option 2: perf tool should depend on proc file system So, this patch uses PERF_COUNT_SW_TASK_CLOCK to get task's execution time instead of reading /proc file. Changelog v2 -> v3: use PERF_COUNT_SW_TASK_CLOCK instead of rusage() as Ingo's suggestion Reported-by: Torok Edwin <edwintorok@gmail.com> Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Xiao Guangrong <ericxiao.gr@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B1F7322.80103@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing/kprobes: Fix field creation's bad error handlingFrederic Weisbecker2009-12-09
| | | | | | | | | | | | | | | | | | | | | When we define the common event fields in kprobe, we invert the error handling and return immediately in case of success. Then we omit to define specific kprobes fields (ip and nargs), and specific kretprobes fields (func, ret_ip, nargs). And we only define them when we fail to create common fields. The most visible consequence is that we can't create filter for k(ret)probes specific fields. This patch re-invert the success/error handling to fix it. Reported-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <1260263815-5167-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf_event: Cleanup for cpu_clock_perf_event_update()Xiao Guangrong2009-12-09
| | | | | | | | | | | | Using atomic64_xchg() instead of atomic64_read() and atomic64_set(). Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B1F19DC.90204@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf_event: Allocate children's perf_event_ctxp at the right timeXiao Guangrong2009-12-09
| | | | | | | | | | | | | | | In current code, children task will allocate memory for 'child->perf_event_ctxp' if the parent is counted, we can do it only if the parent allowed children inherit it. It can save memory and reduce overhead. Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B1F19A8.5040805@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf_event: Clean up __perf_event_init_context()Xiao Guangrong2009-12-09
| | | | | | | | | | | | | | Clean up the code a bit: - define 'perf_cpu_context' variable with 'static' - use kzalloc() instead of kmalloc() and memset() Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B1F194D.7080306@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* hw-breakpoints: Modify breakpoints without unregistering themFrederic Weisbecker2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | Currently, when ptrace needs to modify a breakpoint, like disabling it, changing its address, type or len, it calls modify_user_hw_breakpoint(). This latter will perform the heavy and racy task of unregistering the old breakpoint and registering a new one. This is racy as someone else might steal the reserved breakpoint slot under us, which is undesired as the breakpoint is only supposed to be modified, sometimes in the middle of a debugging workflow. We don't want our slot to be stolen in the middle. So instead of unregistering/registering the breakpoint, just disable it while we modify its breakpoint fields and re-enable it after if necessary. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prasad <prasad@linux.vnet.ibm.com> LKML-Reference: <1260347148-5519-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Update perf-probe documentMasami Hiramatsu2009-12-09
| | | | | | | | | | | | | | | | | | | | | | Add --list and --del option descriptions to perf-probe.txt. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091208220330.10142.73296.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Support --del optionMasami Hiramatsu2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | | Support perf probe --del <event> option. Currently, perf probe can have only one event for each --del option. If you'd like to delete several probe events, you need to specify --del for each events. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091208220323.10142.62079.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* trace-kprobe: Support delete probe syntaxMasami Hiramatsu2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support delete probe syntax. The syntax is "-:[group/]event". Signed-off-by: Masami Hiramatsu <mhiramat@redhat.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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091208220316.10142.39192.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> 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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf probe: Support vmlinux on cwd by defaultMasami Hiramatsu2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | Support vmlinux on current working direcotry by default and also update file-open messages. Now perf probe searches ./vmlinux too. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091208220309.10142.33040.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Remove event suffix number _0Masami Hiramatsu2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | | Remove event suffix number _0 if it is the first. The first event has no suffix, and from the second, each event has suffix number counted from _1. This reduces typing cost :-). Signed-off-by: Masami Hiramatsu <mhiramat@redhat.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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091208220301.10142.50031.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Fix add-probe command syntax without --add optionMasami Hiramatsu2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix add-probe command syntax without --add option. perf-probe supports add-probe command without --add option. But it treats each argument as an event definition. e.g. perf probe func arg1 arg2 is interpreted as perf probe --add func --add arg1 --add arg2 But it may be useless in many cases. This patch fixes this syntax to fold those arguments into one event definition if there is no --add option. With this change, above command is interpreted as below; perf probe --add "func arg1 arg2" Signed-off-by: Masami Hiramatsu <mhiramat@redhat.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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091208220254.10142.73767.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Change probe-added message more user-friendlyMasami Hiramatsu2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change probe-added message more user-friendly expression and show usage of new events. Before: Added new event: p:probe/schedule_0 schedule+10 prev=%ax cpu=%bx After: Added new event: probe:schedule_1 (on schedule+1 with prev cpu) You can now use it on all perf tools, such as: perf record -e probe:schedule_1 -a sleep 1 Signed-off-by: Masami Hiramatsu <mhiramat@redhat.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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091208220247.10142.91642.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Change event list formatMasami Hiramatsu2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change event list format for user readability. perf probe --list shows event list in "[GROUP:EVENT] EVENT-DEFINITION" format, but this format is different from the output of perf-list, and EVENT-DEFINITION is a bit blunt. This patch changes the format to more user friendly one. Before: [probe:schedule_0] schedule+10 prev cpu After: probe:schedule_0 (on schedule+10 with prev cpu) Signed-off-by: Masami Hiramatsu <mhiramat@redhat.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: Frederic Weisbecker <fweisbec@gmail.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> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091208220240.10142.42916.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf: hw_breakpoints: Fix percpu namespace clashStephen Rothwell2009-12-08
| | | | | | | | | | | | | | | | | | | | | | | Today's linux-next build failed with: kernel/hw_breakpoint.c:86: error: 'task_bp_pinned' redeclared as different kind of symbol ... Caused by commit dd17c8f72993f9461e9c19250e3f155d6d99df22 ("percpu: remove per_cpu__ prefix") from the percpu tree interacting with commit 56053170ea2a2c0dc17420e9b94aa3ca51d80408 ("hw-breakpoints: Fix task-bound breakpoint slot allocation") from the tip tree. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <20091208182515.bb6dda4a.sfr@canb.auug.org.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf events: hw_breakpoints: Don't include asm/hw_breakpoint.h in user spaceArnd Bergmann2009-12-07
| | | | | | | | | | | | | asm/hw_breakpoint.h is evidently a kernel internal file and should not be included globally, not even under an #ifdef. Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: K.Prasad <prasad@linux.vnet.ibm.com> LKML-Reference: <200912071712.58650.arnd@arndb.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Use pr_debug for debug messageMasami Hiramatsu2009-12-07
| | | | | | | | | | | | | Use pr_debug() for "missing vmlinux" debugging message. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091207170059.19230.51459.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Check e_snprintf() format stringMasami Hiramatsu2009-12-07
| | | | | | | | | | | | | | Check e_snprintf() format string by gcc, and fix a bug of e_snprintf() caller. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091207170053.19230.7690.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Fix event namelist to duplicate stringMasami Hiramatsu2009-12-07
| | | | | | | | | | | | | | | | | Fix event namelist to duplicate string. Without duplicating, adding multiple probes causes stack overwrite bug, because it reuses a buffer on stack while the buffer is already added in the namelist. String duplication solves this bug because only contents of the buffer is copied to the namelist. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091207170046.19230.55557.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf probe: Fix strtailcmp() to compare s1and s2[0]Juha Leppanen2009-12-07
| | | | | | | | | | | | | | | Fix strtailcmp() to compare s1[0] and s2[0]. strtailcmp() returns 0 if "a" and "b" or "a" and "ab", it's a wrong behavior. This patch fixes it. Signed-off-by: "Juha Leppanen" <juha_motorsportcom@luukku.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Juha Leppanen <juha_motorsportcom@luukku.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091207170040.19230.37464.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86 insn: Delete empty or incomplete inat-tables.cMasami Hiramatsu2009-12-07
| | | | | | | | | | | | | | | Delete empty or incomplete inat-tables.c if gen-insn-attr-x86.awk failed, because it causes a build error if user tries to build kernel next time. Reported-by: Arkadiusz Miskiewicz <arekm@maven.pl> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091207170033.19230.37688.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: Compile insn.c and inat.c only for KPROBESOGAWA Hirofumi2009-12-07
| | | | | | | | | | At least, insn.c and inat.c is needed for kprobe for now. So, this compile those only if KPROBES is enabled. Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Masami Hiramatsu <mhiramat@redhat.com> LKML-Reference: <878wdg8icq.fsf@devron.myhome.or.jp> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf tools: Optimize parse_subsystem_tracepoint_event()Ulrich Drepper2009-12-07
| | | | | | | | | | | | | | | | | | | Uses of strcat are almost always signs that someone is too lazy to think about the code a bit more carefully. One always has to know about the lengths of the strings involved to avoid buffer overflows. This is one case where the size of the object code for me is reduced by 38 bytes. The code should also be faster, especially if flags is non-NULL. Signed-off-by: Ulrich Drepper <drepper@redhat.com> Cc: a.p.zijlstra@chello.nl Cc: fweisbec@gmail.com Cc: jaswinderrajput@gmail.com Cc: paulus@samba.org LKML-Reference: <200912061825.nB6IPUa1023306@hs20-bc2-1.build.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf trace/scripting: Don't display 'scripting unsupported' msg unnecessarilyTom Zanussi2009-12-07
| | | | | | | | | | | | | | | | The 'scripting unsupported' message should only be displayed when the -s or -g options are used, and not when they aren't, as the current code does. Signed-off-by: Tom Zanussi <tzanussi@gmail.com> Cc: rostedt@goodmis.org Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1260163919-6679-3-git-send-email-tzanussi@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'perf/urgent' of ↵Ingo Molnar2009-12-07
|\ | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent
| * hw-breakpoints: Fix task-bound breakpoint slot allocationFrederic Weisbecker2009-12-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Whatever the context nature of a breakpoint, we always perform the following constraint checks before allocating it a slot: - Check the number of pinned breakpoint bound the concerned cpus - Check the max number of task-bound breakpoints that are belonging to a task. - Add both and see if we have a reamining slot for the new breakpoint This is the right thing to do when we are about to register a cpu-only bound breakpoint. But not if we are dealing with a task bound breakpoint. What we want in this case is: - Check the number of pinned breakpoint bound the concerned cpus - Check the number of breakpoints that already belong to the task in which the breakpoint to register is bound to. - Add both This fixes a regression that makes the "firefox -g" command fail to register breakpoints once we deal with a secondary thread. Reported-by: Walt <w41ter@gmail.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Prasad <prasad@linux.vnet.ibm.com>
| * hw-breakpoints: Zeroe the breakpoint attrs on initializationFrederic Weisbecker2009-12-07
| | | | | | | | | | | | | | | | | | The perf attrs used to set up breakpoint parameters are often allocated in the stack and not zeroed out before calling hw_breakpoint_init(). Handle it from this helper to avoid random attributes set by the stack. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Prasad <prasad@linux.vnet.ibm.com>
* | perf trace/scripting: Fix compile error when libperl not installedTom Zanussi2009-12-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When I added the xs callbacks into perf, I forgot to re-check the no-libperl case. This patch fixes the undefined reference error for that. Reported-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: Tom Zanussi <tzanussi@gmail.com> 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> LKML-Reference: <1260153712.6564.4.camel@tropicana> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_event: Eliminate raw->sizeXiao Guangrong2009-12-07
| | | | | | | | | | | | | | | | | | | | | | | | | | raw->size is not used, this patch just cleans it up. Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4B1C8CC4.4050007@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_event: Fix __dsos__write_buildid_table()Xiao Guangrong2009-12-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The remain buff size is 'len - pos->long_name_len - 1', not 'len - pos->long_name_len + 1' This bug was introduced by commit 7691b1e ("perf tools: Misc small fixes"). Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4B1C7F73.80707@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>