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2010-02-08perf record: Fix existing process callgraph symbolaustin_zhang@linux.intel.com1-1/+1
When 'perf record -g' a existing process, even with debuginfo packages, still cannnot get symbol from 'perf report'. try: perf record -g -p `pidof xxx` -f perf report 68.26% :1181 b74870f2 [.] 0x000000b74870f2 | |--32.09%-- 0xb73b5b44 | 0xb7487102 | 0xb748a4e2 | 0xb748633d | 0xb73b41cd | 0xb73b4467 | 0xb747d531 The reason is: for existing process, in __cmd_record(), the pid is 0 rather than the existing process id. Signed-off-by: Austin Zhang <austin_zhang@linux.intel.com> Acked-by: 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: <4710.10.255.24.35.1265389362.squirrel@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-04perf tools: Clean up O_LARGEFILE et al usageXiao Guangrong1-2/+1
Setting _FILE_OFFSET_BITS and using O_LARGEFILE, lseek64, etc, is redundant. Thanks H. Peter Anvin for pointing it out. So, this patch removes O_LARGEFILE, lseek64, etc. Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <4B6A8972.3070605@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-04perf record: Stop intercepting events, use postprocessing to get build-idsArnaldo Carvalho de Melo1-19/+18
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>
2010-02-03perf tools: Use O_LARGEFILE to open perf data fileXiao Guangrong1-1/+4
Open perf data file with O_LARGEFILE flag since its size is easily larger that 2G. For example: # rm -rf perf.data # ./perf kmem record sleep 300 [ perf record: Woken up 0 times to write data ] [ perf record: Captured and wrote 3142.147 MB perf.data (~137282513 samples) ] # ll -h perf.data -rw------- 1 root root 3.1G ..... Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <4B68F32A.9040203@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-31Revert "perf record: Intercept all events"Hitoshi Mitake1-18/+10
This reverts commit f5a2c3dce03621b55f84496f58adc2d1a87ca16f. This patch is required for making "perf lock rec" work. The commit f5a2c3dce0 changes write_event() of builtin-record.c . And changed write_event() sometimes doesn't stop with perf lock rec. 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: <new-submission> [ that commit also causes perf record to not be Ctrl-C-able, and it's concetually wrong to parse the data at record time (unconditionally - even when not needed), as we eventually want to be able to do zero-copy recording, at least for non-archive recordings. ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-29perf session: Create kernel maps in the constructorArnaldo Carvalho de Melo1-5/+0
Removing one extra step needed in the tools that need this, fixing a bug in 'perf probe' where this was not being done. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Masami Hiramatsu <mhiramat@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: <1264633557-17597-4-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16perf record: Intercept all eventsArnaldo Carvalho de Melo1-10/+18
The event interception we need to do in 'perf record' to create a list of all DSOs in PERF_RECORD_MMAP events wasn't seeing all events, make sure that happens by checking size agains event_t->header.size. 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: <1263586107-1756-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16perf record: Encode the domain while synthesizing MMAP eventsArnaldo Carvalho de Melo1-2/+6
In the past 'perf record' had to process only userspace MMAP events, the ones generated in the kernel, but after we reused the MMAP events to encode the module mapings we ended up adding them first to the list of userspace DSOs (dsos__user) and to the kernel one (dsos__kernel). Fix this by encoding the header.misc field and then using it, like other parts to decide the right DSOs list to insert/find. The gotcha here is that since the kernel puts zero in .misc, which isn't PERF_RECORD_MISC_KERNEL (1 << 1), to differentiate, we put 1 in .misc. 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: <1263519930-22803-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13perf tools: Encode kernel module mappings in perf.dataArnaldo Carvalho de Melo1-0/+11
We were always looking at the running machine /proc/modules, even when processing a perf.data file, which only makes sense when we're doing 'perf record' and 'perf report' on the same machine, and in close sucession, or if we don't use modules at all, right Peter? ;-) Now, at 'perf record' time we read /proc/modules, find the long path for modules, and put them as PERF_MMAP events, just like we did to encode the reloc reference symbol for vmlinux. Talking about that now it is encoded in .pgoff, so that we can use .{start,len} to store the address boundaries for the kernel so that when we reconstruct the kmaps tree we can do lookups right away, without having to fixup the end of the kernel maps like we did in the past (and now only in perf record). One more step in the 'perf archive' direction when we'll finally be able to collect data in one machine and analyse in another. 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: <1263396139-4798-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13perf tools: Handle relocatable kernelsArnaldo Carvalho de Melo1-0/+7
DSOs don't have this problem because the kernel emits a PERF_MMAP for each new executable mapping it performs on monitored threads. To fix the kernel case we simulate the same behaviour, by having 'perf record' to synthesize a PERF_MMAP for the kernel, encoded like this: [root@doppio ~]# perf record -a -f sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.344 MB perf.data (~15038 samples) ] [root@doppio ~]# perf report -D | head -10 0xd0 [0x40]: event: 1 . . ... raw event: size 64 bytes . 0000: 01 00 00 00 00 00 40 00 00 00 00 00 00 00 00 00 ......@........ . 0010: 00 00 00 81 ff ff ff ff 00 00 00 00 00 00 00 00 ............... . 0020: 00 00 00 00 00 00 00 00 5b 6b 65 72 6e 65 6c 2e ........ [kernel . 0030: 6b 61 6c 6c 73 79 6d 73 2e 5f 74 65 78 74 5d 00 kallsyms._text] . 0xd0 [0x40]: PERF_RECORD_MMAP 0/0: [0xffffffff81000000((nil)) @ (nil)]: [kernel.kallsyms._text] I.e. we identify such event as having: .pid = 0 .filename = [kernel.kallsyms.REFNAME] .start = REFNAME addr in /proc/kallsyms at 'perf record' time and use now a hardcoded value of '.text' for REFNAME. Then, later, in 'perf report', if there are any kernel hits and thus we need to resolve kernel symbols, we search for REFNAME and if its address changed, relocation happened and we thus must change the kernel mapping routines to one that uses .pgoff as the relocation to apply. This way we use the same mechanism used for the other DSOs and don't have to do a two pass in all the kernel symbols. Reported-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> LKML-Reference: <1262717431-1246-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-28perf record: We should fork only if a program was specified to runArnaldo Carvalho de Melo1-6/+8
IOW: Now 'perf record -a' works, this was a bug introduced in: 856e96608a72412d319e498a3a7c557571f811bd "perf record: Properly synchronize child creation" Also fix the -C usage, i.e. allow for profiling all the tasks in one CPU. Reported-by: Pekka Enberg <penberg@cs.helsinki.fi> 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: <1261957026-15580-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16perf record: Use per-task-per-cpu events for inherited eventsPeter Zijlstra1-2/+2
Create events with a pid and cpu contraint for inherited events so that we get a stream per cpu, instead of all cpus contending on a single stream. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: fweisbec@gmail.com Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091216165904.987643843@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16perf record: Properly synchronize child creationPeter Zijlstra1-38/+71
Remove that ugly usleep and provide proper serialization between parent and child just like perf-stat does. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: fweisbec@gmail.com Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091216165904.908184135@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16perf symbols: Adopt the strlists for dso, commArnaldo Carvalho de Melo1-3/+3
Will be used in perf diff too. 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: <1260914682-29652-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16perf symbols: Make symbol_conf globalArnaldo Carvalho de Melo1-2/+2
This simplifies a lot of functions, less stuff to be done by tool writers. 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: <1260914682-29652-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-15perf record: Rename perf.data to perf.data.old if --force/-f is usedArnaldo Carvalho de Melo1-4/+13
Suggested-by: Steven Rostedt <rostedt@goodmis.org> 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: <1260828571-3613-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-14perf session: Move kmaps to perf_sessionArnaldo Carvalho de Melo1-1/+1
There is still some more work to do to disentangle map creation from DSO loading, but this happens only for the kernel, and for the early adopters of perf diff, where this disentanglement matters most, we'll be testing different kernels, so no problem here. Further clarification: right now we create the kernel maps for the various modules and discontiguous kernel text maps when loading the DSO, we should do it as a two step process, first creating the maps, for multiple mappings with the same DSO store, then doing the dso load just once, for the first hit on one of the maps sharing this DSO backing store. 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: <1260741029-4430-6-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-14perf session: Pass the perf_session to the event handling operationsArnaldo Carvalho de Melo1-4/+7
They will need it to get the right threads list, etc. 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: <1260741029-4430-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12perf tools: Introduce perf_session classArnaldo Carvalho de Melo1-12/+13
That does all the initialization boilerplate, opening the file, reading the header, checking if it is valid, etc. And that will as well have the threads list, kmap (now) global variable, etc, so that we can handle two (or more) perf.data files describing sessions to compare. 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: <1260573842-19720-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23perf record, x86: Print more intelligent error message when sampling failsSimon Kaempflein1-0/+6
Print more accurate error message when "perf record" fails because there is no APIC support, on x86. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-19perf tools: Eliminate some more die() uses in library functionsArnaldo Carvalho de Melo1-2/+5
This time in perf_header__adds_write, propagating the do_write error returns. 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: <1258649757-17554-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-19perf tools: perf_header__read() shouldn't die()Arnaldo Carvalho de Melo1-7/+9
And also don't call the constructor in it, this way it adheres to the model the other methods follow. 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: <1258649757-17554-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-17perf tools: Don't die() in perf_header__new()Arnaldo Carvalho de Melo1-0/+5
Propagate the errors instead, the users are the ones to decide what to do if a library call fails. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.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> LKML-Reference: <1258427892-16312-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-17perf tools: Don't die() in perf_header_attr__add_id()Arnaldo Carvalho de Melo1-1/+4
Propagate the errors instead, the users are the ones to decide what to do if a library call fails. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.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> LKML-Reference: <1258427892-16312-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-17perf tools: Don't die() in perf_header__add_attr()Arnaldo Carvalho de Melo1-1/+4
Propagate the errors instead, the users are the ones to decide what to do if a library call fails. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.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> LKML-Reference: <1258427892-16312-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-17perf tools: Don't die in perf_header_attr__new()Arnaldo Carvalho de Melo1-1/+4
We really should propagate such kinds of errors so that users of these library functions decide what to do in such cases instead of exiting in random places like now. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.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> LKML-Reference: <1258407027-384-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-15Merge commit 'v2.6.32-rc7' into perf/coreIngo Molnar1-1/+1
Merge reason: pick up perf fixlets Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-11perf tools: Use perf_header__set/has_feat whenever possibleFrederic Weisbecker1-2/+2
And drop the alternate checks/sets using set_bit or other kind of helpers. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> LKML-Reference: <1257911467-28276-5-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-11perf tools: Move the build-id storage operations to headersFrederic Weisbecker1-30/+2
So that it makes easier to control it. Especially because we plan to give it a feature section. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> LKML-Reference: <1257911467-28276-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-11perf tools: Synthetize the targeted processFrederic Weisbecker1-1/+10
Don't forget to also synthetize the targeted process from perf record or we'll miss its dso in the events and then we won't be able to deal with its build-id. We are missing it because it is created after the existing synthetized tasks but before the counters are enabled and can send its mapping event. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> LKML-Reference: <1257911467-28276-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-08perf tools: Fix permission checksPekka Enberg1-1/+1
The perf_event_open() system call returns EACCES if the user is not root which results in a very confusing error message: $ perf record -A -a -f Error: perfcounter syscall returned with -1 (Permission denied) Fatal: No CONFIG_PERF_EVENTS=y kernel support configured? It turns out that's because perf tools are checking only for EPERM. Fix that up to get a much better error message: $ perf record -A -a -f Fatal: Permission error - are you root? Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1257696066-4046-1-git-send-email-penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-08perf symbols: Use the buildids if presentArnaldo Carvalho de Melo1-3/+46
With this change 'perf record' will intercept PERF_RECORD_MMAP calls, creating a linked list of DSOs, then when the session finishes, it will traverse this list and read the buildids, stashing them at the end of the file and will set up a new feature bit in the header bitmask. 'perf report' will then notice this feature and populate the 'dsos' list and set the build ids. When reading the symtabs it will refuse to load from a file that doesn't have the same build id. This improves the reliability of the profiler output, as symbols and profiling data is more guaranteed to match. Example: [root@doppio ~]# perf report | head /home/acme/bin/perf with build id b1ea544ac3746e7538972548a09aadecc5753868 not found, continuing without symbols # Samples: 2621434559 # # Overhead Command Shared Object Symbol # ........ ............... ............................. ...... # 7.91% init [kernel] [k] read_hpet 7.64% init [kernel] [k] mwait_idle_with_hints 7.60% swapper [kernel] [k] read_hpet 7.60% swapper [kernel] [k] mwait_idle_with_hints 3.65% init [kernel] [k] 0xffffffffa02339d9 [root@doppio ~]# In this case the 'perf' binary was an older one, vanished, so its symbols probably wouldn't match or would cause subtly different (and misleading) output. Next patches will support the kernel as well, reading the build id notes for it and the modules from /sys. Another patch should also introduce a new plumbing command: 'perf list-buildids' that will then be used in porcelain that is distro specific to fetch -debuginfo packages where such buildids are present. This will in turn allow for one to run 'perf record' in one machine and 'perf report' in another. Future work on having the buildid sent directly from the kernel in the PERF_RECORD_MMAP event is needed to close races, as the DSO can be changed during a 'perf record' session, but this patch at least helps with non-corner cases and current/older kernels. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.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: Jim Keniston <jkenisto@us.ibm.com> Cc: K. Prasad <prasad@linux.vnet.ibm.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roland McGrath <roland@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1257367843-26224-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-27perf tools: Generalize event synthesizing routinesArnaldo Carvalho de Melo1-171/+10
Because we will need it in 'perf top' to support userspace symbols for existing threads. Now we pass a callback that will receive the synthesized event and then write it to the output file in 'perf record' and in the upcoming patch for 'perf top' we will just immediatelly create the in memory representation of threads and maps. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1256592199-9608-2-git-send-email-acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-27perf record: Fix race where process can disappear while reading its /proc/pid/tasksArnaldo Carvalho de Melo1-0/+4
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1256592199-9608-1-git-send-email-acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-23perf tools: Unify debug messages mechanismsArnaldo Carvalho de Melo1-1/+1
We were using eprintf in some places, that looks at a global 'verbose' level, and at other places passing a 'v' parameter to specify the verbosity level, unify it by introducing pr_{err,warning,debug,etc}, just like in the kernel. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1256153646-10097-1-git-send-email-acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-19perf tools: Introduce bitmask'ed additional headersFrederic Weisbecker1-2/+2
This provides a new set of bitmasked headers. A new field is added in the perf headers that implements a bitmap storing optional features present in the perf.data file. The layout can be pictured like this: (Usual perf headers)(Features bitmap)[Feature 0][Feature n][Feature 255] If the bit n is set, then the feature n is used in this file. They are all set in order. This brings a backward and forward compatibility. The trace_info section has moved into such optional features, this is the first and only one for now. This is backward compatible with the .32 file version although it doesn't support the previous separate trace.info file. And finally it doesn't support the current interim development version. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1255792354-11304-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-19perf tools: Use kernel bitmap libraryFrederic Weisbecker1-3/+0
Use the kernel bitmap library for internal perf tools uses. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1255792354-11304-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-15perf trace: Add filter SuppportLi Zefan1-1/+14
Add a new option "--filter <filter_str>" to perf record, and it should be right after "-e trace_point": #./perf record -R -f -e irq:irq_handler_entry --filter irq==18 ^C # ./perf trace perf-4303 ... irq_handler_entry: irq=18 handler=eth0 init-0 ... irq_handler_entry: irq=18 handler=eth0 init-0 ... irq_handler_entry: irq=18 handler=eth0 init-0 ... irq_handler_entry: irq=18 handler=eth0 init-0 ... irq_handler_entry: irq=18 handler=eth0 See Documentation/trace/events.txt for the syntax of filter expressions. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <4AD6955F.90602@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-12perf tools: Fix counter sample frequency breakageMike Galbraith1-1/+13
Commit 42e59d7d19dc4b4 switched to a default sample frequency of 1KHz, which overrides any user supplied count, causing sched, top and timechart to miss events due to their discrete events being flagged PERF_SAMPLE_PERIOD. Override default sample frequency when the user profides a period count, and make both record and top honor that user supplied option. Signed-off-by: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arjan van de Ven <arjan@infradead.org> LKML-Reference: <1255326963.15107.2.camel@marge.simson.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-07perf tools: Merge trace.info content into perf.dataFrederic Weisbecker1-4/+3
This drops the trace.info file and move its contents into the common perf.data file. This is done by creating a new trace_info section into this file. A user of perf headers needs to call perf_header__set_trace_info() to save the trace meta informations into the perf.data file. A file created by perf after his patch is unsupported by previous version because the size of the headers have increased. That said, it's two new fields that have been added in the end of the headers, and those could be ignored by previous versions if they just handled the dynamic header size and then ignore the unknow part. The offsets guarantee the compatibility. We'll do a -stable fix for that. But current previous versions handle the header size using its static size, not dynamic, then it's not backward compatible with trace records. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091006213643.GA5343@nowhere> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-06perf tools: Default to 1 KHz auto-sampling freq eventsIngo Molnar1-26/+26
Use auto-freq events by default in perf record and perf top. This allows more consistent hardware event sampling, regardless of the intensity of the underlying event. It also keeps us from over-sampling on larger/busier systems. (also make surrounding initializations more consistent) 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: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-04perf: Propagate term signal to childChris Wilson1-0/+6
If we launch the child on behalf of the user, ensure that it dies along with ourselves when we are interrupted. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Chris Wilson <chris@chris-wilson.co.uk> LKML-Reference: <1254616502-4728-1-git-send-email-chris@chris-wilson.co.uk> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-21perf: Do the big rename: Performance Counters -> Performance EventsIngo Molnar1-11/+11
Bye-bye Performance Counters, welcome Performance Events! In the past few months the perfcounters subsystem has grown out its initial role of counting hardware events, and has become (and is becoming) a much broader generic event enumeration, reporting, logging, monitoring, analysis facility. Naming its core object 'perf_counter' and naming the subsystem 'perfcounters' has become more and more of a misnomer. With pending code like hw-breakpoints support the 'counter' name is less and less appropriate. All in one, we've decided to rename the subsystem to 'performance events' and to propagate this rename through all fields, variables and API names. (in an ABI compatible fashion) The word 'event' is also a bit shorter than 'counter' - which makes it slightly more convenient to write/handle as well. Thanks goes to Stephane Eranian who first observed this misnomer and suggested a rename. User-space tooling and ABI compatibility is not affected - this patch should be function-invariant. (Also, defconfigs were not touched to keep the size down.) This patch has been generated via the following script: FILES=$(find * -type f | grep -vE 'oprofile|[^K]config') sed -i \ -e 's/PERF_EVENT_/PERF_RECORD_/g' \ -e 's/PERF_COUNTER/PERF_EVENT/g' \ -e 's/perf_counter/perf_event/g' \ -e 's/nb_counters/nb_events/g' \ -e 's/swcounter/swevent/g' \ -e 's/tpcounter_event/tp_event/g' \ $FILES for N in $(find . -name perf_counter.[ch]); do M=$(echo $N | sed 's/perf_counter/perf_event/g') mv $N $M done FILES=$(find . -name perf_event.*) sed -i \ -e 's/COUNTER_MASK/REG_MASK/g' \ -e 's/COUNTER/EVENT/g' \ -e 's/\<event\>/event_id/g' \ -e 's/counter/event/g' \ -e 's/Counter/Event/g' \ $FILES ... to keep it as correct as possible. This script can also be used by anyone who has pending perfcounters patches - it converts a Linux kernel tree over to the new naming. We tried to time this change to the point in time where the amount of pending patches is the smallest: the end of the merge window. Namespace clashes were fixed up in a preparatory patch - and some stylistic fallout will be fixed up in a subsequent patch. ( NOTE: 'counters' are still the proper terminology when we deal with hardware registers - and these sed scripts are a bit over-eager in renaming them. I've undone some of that, but in case there's something left where 'counter' would be better than 'event' we can undo that on an individual basis instead of touching an otherwise nicely automated patch. ) Suggested-by: Stephane Eranian <eranian@google.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Paul Mackerras <paulus@samba.org> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Howells <dhowells@redhat.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <linux-arch@vger.kernel.org> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-17perf record: Disable profiling before draining the bufferPeter Zijlstra1-1/+12
I noticed that perf-record continues profiling itself after the child terminated and we're draining the buffer. This can cause a _lot_ of overhead with --all recording - we keep and keep recording, which produces new and new events. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-14perf tools: Implement counter output multiplexingIngo Molnar1-17/+26
Finish the -M/--multiplex option implementation: - separate it out from group_fd - correctly set it via the ioctl and dont mmap counters that are multiplexed - modify the perf record event loop to deal with buffer-less counters. - remove the -g option from perf sched record - account for unordered events in perf sched latency - (add -f to perf sched record to ease measurements) - skip idle threads (pid==0) in latency output The result is better latency output by 'perf sched latency': ----------------------------------------------------------------------------------- Task | Runtime ms | Switches | Average delay ms | Maximum delay ms | ----------------------------------------------------------------------------------- ksoftirqd/8 | 0.071 ms | 2 | avg: 0.458 ms | max: 0.913 ms | at-spi-registry | 0.609 ms | 19 | avg: 0.013 ms | max: 0.023 ms | perf | 3.316 ms | 16 | avg: 0.013 ms | max: 0.054 ms | Xorg | 0.392 ms | 19 | avg: 0.011 ms | max: 0.018 ms | sleep | 0.537 ms | 2 | avg: 0.009 ms | max: 0.009 ms | ----------------------------------------------------------------------------------- TOTAL: | 4.925 ms | 58 | --------------------------------------------- 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: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-14perf tools: Add an option to multiplex counters in a single channelFrederic Weisbecker1-0/+6
Add an option to multiplex counters output in the channel of the group leader, ie: the first counter opened: -M --multiplex The effect is better serialized samples. This is especially useful for tracepoint samples that need to be well serialized for their post-processing. Also make use of this option in 'perf sched'. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> 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> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-03perf trace: Sample timestamps as wellIngo Molnar1-0/+1
Before: perf-21082 [013] 0.000000: sched_wakeup_new: task perf:21083 [120] success=1 [015] perf-21082 [013] 0.000000: sched_migrate_task: task perf:21082 [120] from: 13 to: 15 perf-21082 [013] 0.000000: sched_process_fork: parent perf:21082 child perf:21083 true-21083 [015] 0.000000: sched_wakeup: task migration/15:33 [0] success=1 [015] perf-21082 [013] 0.000000: sched_switch: task perf:21082 [120] (S) ==> swapper:0 [140] true-21083 [015] 0.000000: sched_switch: task perf:21083 [120] (R) ==> migration/15:33 [0] true-21083 [011] 0.000000: sched_process_exit: task true:21083 [120] After: perf-21082 [013] 14674.797613: sched_wakeup_new: task perf:21083 [120] success=1 [015] perf-21082 [013] 14674.797506: sched_migrate_task: task perf:21082 [120] from: 13 to: 15 perf-21082 [013] 14674.797610: sched_process_fork: parent perf:21082 child perf:21083 true-21083 [015] 14674.797725: sched_wakeup: task migration/15:33 [0] success=1 [015] perf-21082 [013] 14674.797722: sched_switch: task perf:21082 [120] (S) ==> swapper:0 [140] true-21083 [015] 14674.797729: sched_switch: task perf:21083 [120] (R) ==> migration/15:33 [0] true-21083 [011] 14674.798159: sched_process_exit: task true:21083 [120] 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: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-02perf trace: Sample the CPU tooIngo Molnar1-1/+3
Sample, record, parse and print the CPU field - it had all zeroes before. Before (watch the second column, the CPU values): perf-32685 [000] 0.000000: sched_wakeup_new: task perf:32686 [120] success=1 [011] perf-32685 [000] 0.000000: sched_migrate_task: task perf:32685 [120] from: 1 to: 11 perf-32685 [000] 0.000000: sched_process_fork: parent perf:32685 child perf:32686 true-32686 [000] 0.000000: sched_wakeup: task migration/11:25 [0] success=1 [011] true-32686 [000] 0.000000: sched_wakeup: task distccd:12793 [125] success=1 [015] true-32686 [000] 0.000000: sched_wakeup: task distccd:12793 [125] success=1 [015] perf-32685 [000] 0.000000: sched_switch: task perf:32685 [120] (S) ==> swapper:0 [140] true-32686 [000] 0.000000: sched_switch: task perf:32686 [120] (R) ==> migration/11:25 [0] true-32686 [000] 0.000000: sched_switch: task perf:32686 [120] (R) ==> distccd:12793 [125] true-32686 [000] 0.000000: sched_switch: task true:32686 [120] (R) ==> distccd:12793 [125] true-32686 [000] 0.000000: sched_process_exit: task true:32686 [120] true-32686 [000] 0.000000: sched_stat_wait: task: distccd:12793 wait: 6767985949080 [ns] true-32686 [000] 0.000000: sched_stat_wait: task: distccd:12793 wait: 6767986139446 [ns] true-32686 [000] 0.000000: sched_stat_sleep: task: distccd:12793 sleep: 132844 [ns] true-32686 [000] 0.000000: sched_stat_sleep: task: distccd:12793 sleep: 131724 [ns] After: perf-32685 [001] 0.000000: sched_wakeup_new: task perf:32686 [120] success=1 [011] perf-32685 [001] 0.000000: sched_migrate_task: task perf:32685 [120] from: 1 to: 11 perf-32685 [001] 0.000000: sched_process_fork: parent perf:32685 child perf:32686 true-32686 [011] 0.000000: sched_wakeup: task migration/11:25 [0] success=1 [011] true-32686 [015] 0.000000: sched_wakeup: task distccd:12793 [125] success=1 [015] true-32686 [015] 0.000000: sched_wakeup: task distccd:12793 [125] success=1 [015] perf-32685 [001] 0.000000: sched_switch: task perf:32685 [120] (S) ==> swapper:0 [140] true-32686 [011] 0.000000: sched_switch: task perf:32686 [120] (R) ==> migration/11:25 [0] true-32686 [015] 0.000000: sched_switch: task perf:32686 [120] (R) ==> distccd:12793 [125] true-32686 [015] 0.000000: sched_switch: task true:32686 [120] (R) ==> distccd:12793 [125] true-32686 [015] 0.000000: sched_process_exit: task true:32686 [120] true-32686 [015] 0.000000: sched_stat_wait: task: distccd:12793 wait: 6767985949080 [ns] true-32686 [015] 0.000000: sched_stat_wait: task: distccd:12793 wait: 6767986139446 [ns] true-32686 [015] 0.000000: sched_stat_sleep: task: distccd:12793 sleep: 132844 [ns] true-32686 [015] 0.000000: sched_stat_sleep: task: distccd:12793 sleep: 131724 [ns] So we can now see how this workload migrated between CPUs. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-28perf tools: Only save the event formats we needFrederic Weisbecker1-2/+2
While opening a trace event counter, every events are saved in the trace.info file. But we only want to save the specifications of the events we are using. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1251421798-9101-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18perf tools: Record events info also when :record suffix is used.Frederic Weisbecker1-3/+11
You can enable a counter's PERF_SAMPLE_RAW attribute in two fashions: - using the -R option (every counters get PERF_SAMPLE_RAW) - using the :record suffix in a trace event counter name Currently we record the events info in a trace.info file from perf record when the former method is used but we omit it with the latter. Check both situations. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1250543271-8383-3-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>