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2010-01-16perf symbols: Cache /proc/kallsyms files by build-idArnaldo Carvalho de Melo1-13/+35
So that when we don't have a vmlinux handy we can store the kallsyms for later use by 'perf report'. 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: <1263501006-14185-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16perf symbols: Don't try to load kallsyms if doesn't match the record build-idArnaldo Carvalho de Melo1-5/+8
Now a perf.data file collected on a x86_64 fedora 12 machine gets properly parsed on a Debian testing PARISC64 machine with 32-bit userland: acme@parisc:~/git/linux-2.6-tip$ perf report 2> /dev/null | head -15 # Samples: 293085637 # # Overhead Command Shared Object Symbol # ........ ............... ................................. ...... # 35.11% find [kernel.kallsyms] [k] 0xffffffff81002b5a 18.25% perf [kernel.kallsyms] [k] 0xffffffff8102235f 9.07% find find [.] 0x0000000000fb0e 5.80% swapper [kernel.kallsyms] [k] 0xffffffff8102235f 3.29% perf libc-2.10.2.so [.] __GI_strcmp 2.70% find libc-2.10.2.so [.] __GI_memmove 2.33% init [kernel.kallsyms] [k] 0xffffffff810091b9 2.03% find libc-2.10.2.so [.] _int_malloc 1.67% find libc-2.10.2.so [.] _IO_vfprintf_internal 1.65% sshd libcrypto.so.0.9.8k [.] 0x00000000105440 acme@parisc:~/git/linux-2.6-tip$ 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: <1263501006-14185-2-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 Melo1-32/+84
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 symbols: Record the domain of DSOs in HEADER_BUILD_ID header tableArnaldo Carvalho de Melo1-3/+3
So that we can restore them to the right DSO list (either dsos__kernel or dsos__user). We do that just like the kernel does for the other events, encoding PERF_RECORD_MISC_{KERNEL,USER} in perf_event_header. 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: <1262901583-8074-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13perf tools: Handle relocatable kernelsArnaldo Carvalho de Melo1-2/+5
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>
2010-01-13perf session: Keep pointers to the vmlinux mapsArnaldo Carvalho de Melo1-16/+13
So that tools such as 'perf probe' don't have to lookup '[kernel.kallsyms]' but instead access them directly after perf_session__create_kernel_maps or map_groups__create_kernel_maps. 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: <1262629169-22797-4-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13perf symbols: Export symbol_type__is_aArnaldo Carvalho de Melo1-1/+1
Will be needed by the new HEADER_DSO_INFO feature that will be a HEADER_BUILD_ID superset, replacing it. 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: <1262629169-22797-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13perf symbols: Generalise the kallsyms parsing routineArnaldo Carvalho de Melo1-26/+48
Will be used to find an specific symbol by name on 'perf record' to support relocation reference symbols to support relocatable kernels. Still have to conver the perf trace tools to use it instead of their current reimplementation. 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: <1262629169-22797-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-28perf record: Introduce a symtab cacheArnaldo Carvalho de Melo1-4/+13
Now a cache will be created in a ~/.debug debuginfo like hierarchy, so that at the end of a 'perf record' session all the binaries (with build-ids) involved get collected and indexed by their build-ids, so that perf report can find them. This is interesting when developing software where you want to do a 'perf diff' with the previous build and opens avenues for lots more interesting tools, like a 'perf diff --graph' that takes more than two binaries into account. Tunables for collecting just the symtabs can be added if one doesn't want to have the full binary, but having the full binary allows things like 'perf rerecord' or other tools that can re-run the tests by having access to the exact binary in some perf.data file, so it may well be interesting to keep the full binary there. Space consumption is minimised by trying to use hard links, a 'perf cache' tool to manage the space used, a la ccache is required to purge older entries. With this in place it will be possible also to introduce new commands, 'perf archive' and 'perf restore' (or some more suitable and future proof names) to create a cpio/tar file with the perf data and the files in the cache that _had_ perf hits of interest. There are more aspects to polish, like finding the right vmlinux file to cache, etc, but this is enough for a first step. 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: <1261957026-15580-10-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16perf report: Generalize perf_session__fprintf_hists()Arnaldo Carvalho de Melo1-0/+1
Pull it out of builtin-report - further changes will be made and it will then be reusable in 'perf diff' as well. 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: <1260914682-29652-4-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16perf symbols: Move symbol filtering to event__preprocess_sample()Arnaldo Carvalho de Melo1-0/+5
So that --dsos, --comm, --symbols can bem used in more tools, like in perf diff: $ perf record -f find / > /dev/null $ perf record -f find / > /dev/null $ perf diff --dsos /lib64/libc-2.10.1.so | head -5 1 +22392124 /lib64/libc-2.10.1.so _IO_vfprintf_internal 2 +6410655 /lib64/libc-2.10.1.so __GI_memmove 3 +1 +9192692 /lib64/libc-2.10.1.so _int_malloc 4 -1 -15158605 /lib64/libc-2.10.1.so _int_free 5 +45669 /lib64/libc-2.10.1.so _IO_new_file_xsputn $ 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: <1260914682-29652-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16perf symbols: Adopt the strlists for dso, commArnaldo Carvalho de Melo1-0/+33
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 Melo1-23/+15
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>
2009-12-14perf session: Move kmaps to perf_sessionArnaldo Carvalho de Melo1-45/+44
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>
2009-12-12perf symbols: Ditch dso->find_symbolArnaldo Carvalho de Melo1-2/+0
It is always wired to dso__find_symbol. 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: <1260564999-13371-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12perf symbols: Allow lookups by symbol name tooArnaldo Carvalho de Melo1-8/+96
Configurable via symbol_conf.sort_by_name, so that the cost of an extra rb_node on all 'struct symbol' instances is not paid by tools that only want to decode addresses. How to use it: symbol_conf.sort_by_name = true; symbol_init(&symbol_conf); struct map *map = map_groups__find_by_name(kmaps, MAP__VARIABLE, "[kernel.kallsyms]"); if (map == NULL) { pr_err("couldn't find map!\n"); kernel_maps__fprintf(stdout); } else { struct symbol *sym = map__find_symbol_by_name(map, sym_filter, NULL); if (sym == NULL) pr_err("couldn't find symbol %s!\n", sym_filter); else pr_info("symbol %s: %#Lx-%#Lx \n", sym_filter, sym->start, sym->end); } Looking over the vmlinux/kallsyms is common enough that I'll add a variable to the upcoming struct perf_session to avoid the need to use map_groups__find_by_name to get the main vmlinux/kallsyms map. The above example looks on the 'variable' symtab, but it is just like that for the functions one. Also the sort operation is done when we first use map__find_symbol_by_name, in a lazy way. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1260564622-12392-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12perf symbols: Add support for 'variable' symtabsArnaldo Carvalho de Melo1-15/+51
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>
2009-12-12perf symbols: Introduce ELF counterparts to symbol_type__is_aArnaldo Carvalho de Melo1-2/+22
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>
2009-12-12perf symbols: Introduce symbol_type__is_aArnaldo Carvalho de Melo1-4/+11
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>
2009-12-12perf symbols: Rename kthreads to kmaps, using another abstraction for itArnaldo Carvalho de Melo1-36/+37
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>
2009-12-10perf symbols: dsos__read_build_ids() should read both user and kernel buildidsArnaldo Carvalho de Melo1-2/+3
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>
2009-11-27perf tools: Consolidate symbol resolving across all toolsArnaldo Carvalho de Melo1-24/+2
Now we have a very high level routine for simple tools to process IP sample events: int event__preprocess_sample(const event_t *self, struct addr_location *al, symbol_filter_t filter) It receives the event itself and will insert new threads in the global threads list and resolve the map and symbol, filling all this info into the new addr_location struct, so that tools like annotate and report can further process the event by creating hist_entries in their specific way (with or without callgraphs, etc). It in turn uses the new next layer function: void thread__find_addr_location(struct thread *self, u8 cpumode, enum map_type type, u64 addr, struct addr_location *al, symbol_filter_t filter) This one will, given a thread (userspace or the kernel kthread one), will find the given type (MAP__FUNCTION now, MAP__VARIABLE too in the near future) at the given cpumode, taking vdsos into account (userspace hit, but kernel symbol) and will fill all these details in the addr_location given. Tools that need a more compact API for plain function resolution, like 'kmem', can use this other one: struct symbol *thread__find_function(struct thread *self, u64 addr, symbol_filter_t filter) So, to resolve a kernel symbol, that is all the 'kmem' tool needs, its just a matter of calling: sym = thread__find_function(kthread, addr, NULL); The 'filter' parameter is needed because we do lazy parsing/loading of ELF symtabs or /proc/kallsyms. With this we remove more code duplication all around, which is always good, huh? :-) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: John Kacur <jkacur@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1259346563-12568-12-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: When not using modules, discard its symbolsArnaldo Carvalho de Melo1-1/+5
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: <1259346563-12568-10-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Support multiple symtabs in struct threadArnaldo Carvalho de Melo1-99/+58
Making the routines that were so far specific to the kernel maps useful for all threads. This is done by making the kernel maps be contained in a kernel "thread". This gets the kernel specific routines closer to the userspace counterparts, which will help in reducing the boilerplate for resolving a symbol, as will be demonstrated in the next patches. 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: <1259346563-12568-9-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Kernel_maps should be an array of MAP__NR_TYPES entriesArnaldo Carvalho de Melo1-13/+38
So that we can support multiple symbol table types. 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: <1259346563-12568-8-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Make the kallsyms loading routines part of the dso classArnaldo Carvalho de Melo1-39/+38
So that the kallsyms loading routines are the direct counterpart of the vmlinux loading ones, i.e. dso__load_kallsyms is the counterpart of dso__load_vmlinux. In the process make them also use the symbols rb tree indexed by map->type, paving the way for supporting other types of symtabs, such as the next one to be supported: variables. This also allowed removal of yet another global variable: kernel_map__functions. 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: <1259346563-12568-7-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Better support for multiple symbol tables per dsoArnaldo Carvalho de Melo1-23/+36
By using an array of rb_roots in struct dso we can, from a struct map instance to get the right symbol rb_tree more easily. This way we can have just one symbol lookup method for struct map instances, map__find_symbol, instead of one per symtab type (functions, variables). 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: <1259346563-12568-6-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Add a 'type' field to struct mapArnaldo Carvalho de Melo1-10/+21
That way we will be able to check if the right symtab is loaded in the underlying DSO. 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: <1259346563-12568-5-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Unexport kernel_map__functionsArnaldo Carvalho de Melo1-2/+1
perf annotate was the only user, and it doesn't really need it. 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: <1259346563-12568-4-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Split the dsos list into kernel and user partsArnaldo Carvalho de Melo1-19/+37
We don't need to look at modules in dsos__findnew because the kernel events come only with user DSOs. Also we need a way to list just the module DSOs so that we can create multiple sets of maps, now that we will support maps for the variables in a symtab. 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: <1259346563-12568-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Rename kernel_mapto kernel_map[s]__functionsArnaldo Carvalho de Melo1-23/+23
As we'll have kernel_map[s]__variables 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: <1259346563-12568-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27perf symbols: Avoid annoying message about loading symbolsArnaldo Carvalho de Melo1-0/+1
This should be properly fixed when we remove the XXX comment in 'perf report', function resolve_symbol. 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: <1259346563-12568-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-24perf symbols: Rename find_symbol routines to find_functionArnaldo Carvalho de Melo1-31/+37
Paving the way for supporting variable in adition to function symbols. 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: <1259074912-5924-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-24perf tools: Introduce zalloc() for the common calloc(1, N) caseArnaldo Carvalho de Melo1-6/+5
This way we type less characters and it looks more like the kzalloc kernel counterpart. 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: <1259071517-3242-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-24perf symbols: Simplify symbol machinery setupArnaldo Carvalho de Melo1-10/+21
And also express its configuration toggles via a struct. Now all one has to do is to call symbol__init(NULL) if the defaults are OK, or pass a struct symbol_conf pointer with the desired configuration. If a tool uses kernel_maps__find_symbol() to look at the kernel and modules mappings for a symbol but didn't call symbol__init() first, that will generate a one time warning too, alerting the subcommand developer that symbol__init() must be called. 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: <1259071517-3242-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23perf symbols: Look for vmlinux in more placesArnaldo Carvalho de Melo1-12/+101
Now that we can check the buildid to see if it really matches, this can be done safely: vmlinux /boot/vmlinux /boot/vmlinux-<uts.release> /lib/modules/<uts.release>/build/vmlinux /usr/lib/debug/lib/modules/%s/vmlinux More can be added - if you know about distros that put the vmlinux somewhere else please let us know. 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: <1259001550-8194-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22perf symbols: Show messages about module loading only if verbose >= 1Arnaldo Carvalho de Melo1-3/+3
Suggested-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> LKML-Reference: <1258903301-20584-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22perf symbols: Fix ELF header errors during "perf kmem record"Pekka Enberg1-0/+5
The write_event() function in builtin-record.c writes out all mmap()'d DSOs including non-ELF files like GNOME resource files and such. Therefore, check for ELF_K_ELF in filename__read_build_id() before attempting to read the ELF header with gelf_getehdr(). Fixes the following error messages when running "perf kmem record": penberg@penberg-laptop:~/src/linux/tools/perf$ perf kmem record ^C[ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.753 MB perf.data (~32885 samples) ] filename__read_build_id: cannot get elf header. filename__read_build_id: cannot get elf header. filename__read_build_id: cannot get elf header. filename__read_build_id: cannot get elf header. filename__read_build_id: cannot get elf header. filename__read_build_id: cannot get elf header. filename__read_build_id: cannot get elf header. filename__read_build_id: cannot get elf header. filename__read_build_id: cannot get elf header. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1258885784-11709-1-git-send-email-penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21perf symbols: Old versions of elf.h don't have NT_GNU_BUILD_IDArnaldo Carvalho de Melo1-0/+4
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: <1258821086-11521-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21perf symbols: Fixup kernel_maps__fixup_end end mapArnaldo Carvalho de Melo1-7/+10
We better call this routine after both the kernel and modules are loaded, because as it was if there weren't modules it would not be called, resulting in kernel_map->end remaining at zero, so no map would be found and consequently the kernel symtab wouldn't get loaded, i.e. no kernel symbols would be resolved. Also this fixes another case, that is when we _have_ modules, but the last map would have its ->end address not set before we loaded its symbols, which would never happen because ->end was not set. 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> LKML-Reference: <1258821086-11521-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21perf symbols: Change the kernel DSO name if it comes from kallsymsArnaldo Carvalho de Melo1-1/+6
So that the user have a clearer indication about the source of the symbols, as we only state buildid mismatches in verbose mode, because 'perf top' would overwrite such warning anyway. 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: <1258757489-5978-6-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21perf symbols: Check vmlinux buildidArnaldo Carvalho de Melo1-2/+26
E.g.: [root@doppio linux-2.6-tip]# perf top -v --vmlinux ../build/tip/vmlinux > /dev/null build_id in vmlinux is e96699725a47413a50c231864a8e7a8ced40a31b while expected is 18e7cc53db62a7d35e9d6f6c9ddc23017d38ee9a, ignoring it I.e. perf top was told to use a vmlinux file that is not the one currently running on the machine, it ignores it and falls back to using /proc/kallsyms. This solves many, at first, mysterious results when people have a stale vmlinux file while keeping the default of trying to use the vmlinux file in the current directory in things like 'perf annotate' where the DWARF info is required and thus we can't use just /proc/kallsyms. Modules buildids are already being checked as of the previous changeset in this series, because we are using the default dso__load routine, that will look at a series of places looking for the best file with a matching buildid, starting in the -debuginfo directories. 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: <1258757489-5978-5-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21perf symbols: Do lazy symtab loading for the kernel & modules tooArnaldo Carvalho de Melo1-114/+59
Just like we do with the other DSOs. This also simplifies the kernel_maps setup process, now all that the tools need to do is to call kernel_maps__init and the maps for the modules and kernel will be created, then, later, when kernel_maps__find_symbol() is used, it will also call maps__find_symbol that already checks if the symtab was loaded, loading it if needed. Now if one does 'perf top --hide_kernel_symbols' we won't pay the price of loading the (many) symbols in /proc/kallsyms or vmlinux. 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: <1258757489-5978-4-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21perf symbols: Introduce dso__build_id_equalArnaldo Carvalho de Melo1-2/+6
Will be used in more places. 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: <1258757489-5978-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21perf symbols: Filename__read_build_id should look at .notes section tooArnaldo Carvalho de Melo1-9/+38
In the kernel we have more than one notes section, so the linker script combines all and puts them into a ".notes" combined section. So we need to look at both sections and also traverse them looking at multiple GElf_Nhdr entries till we find the one we want, with the build_id. 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: <1258757489-5978-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21perf symbols: Remove unrelated actions from dso__load_kernel_symArnaldo Carvalho de Melo1-27/+19
It should just load kernel symbols, not load the list of modules. There are more stuff to move to other routines, but lets do it in several steps. End goal is to be able to defer symbol table loading till we find a hit for that map address range. So that the kernel & modules are handled just like all the other DSOs in the system. 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: <1258757489-5978-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-19perf symbols: Capture the running kernel buildid tooArnaldo Carvalho de Melo1-28/+37
[root@doppio linux-2.6-tip]# perf record -a -f sleep 3s ; perf buildid-list | grep vmlinux [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.171 MB perf.data (~7489 samples) ] 18e7cc53db62a7d35e9d6f6c9ddc23017d38ee9a vmlinux [root@doppio linux-2.6-tip]# Several refactorings were needed so that we can have symmetry between dsos__load_modules() and dsos__load_kernel(), i.e. those functions will respectively create and add to the dsos list the loaded modules and kernel, with its buildids, but not load its symbols. That is something the subcomands that need will have to call dso__load_kernel_sym(), just like we do with modules with dsos__load_module_sym()/dso__load_module_sym(). Next csets will actually use this info to stop producing bogus results using mismatched vmlinux and .ko files. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Roland McGrath <roland@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: <1258582853-8579-4-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-19perf symbols: Record the build_ids of kernel modules tooArnaldo Carvalho de Melo1-1/+52
[root@doppio linux-2.6-tip]# perf record -a sleep 2s;perf buildid-list|tail [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.162 MB perf.data (~7078 samples) ] 881588fa57b3c1696bc91e5e804a11304f093535 [cfg80211] 4d47ce1da9d16bad00c962c072451b7c681e82df [snd_page_alloc] 5146377e89a7caac617f9782f1a02e46263d3a31 [rfkill] 2153b937bff0d345fea83b63a2e1d3138569f83d [i915] 4e6fb1bb97362e3ee4d306988b9ad6912d5fb9ae [drm_kms_helper] f56ef2bf853e3a798f0d8d51f797622e5dc4420e [drm] b0d157a3b5c4e017329ffc07c64623cd6ad65e95 [i2c_algo_bit] 8125374b905ef9fa8b65d98e166b008ad952f198 [i2c_core] fc875c6e5a90e7b915e9d445d0efc859e1b2678c [video] 4b43c5006589f977e9762fdfc7ac1a92b72fca52 [output] [root@doppio linux-2.6-tip]# elfutils libdwfl/linux-kernel-modules.c was used as reference, as suggested by Roland McGrath. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Roland McGrath <roland@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: <1258582853-8579-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-19perf symbols: Kill struct build_id_list and die() another dayArnaldo Carvalho de Melo1-28/+9
No need for this struct and its allocations, we can just use the ->build_id member we already have in struct dso, then ask for it to be read, and later traverse the dsos list, writing the buildid table to the perf.data file. As a bonus, one more die() function got killed. 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: <1258582853-8579-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-19perf symbols: Fix comparision of build_idsArnaldo Carvalho de Melo1-36/+16
When we read the build_id from the DSO name to then index into /usr/lib/debug/.buildid/DSO_BUILD_ID[0:2]/DSO_BUILD_ID[2:], we were jumping directly to the comparision with the buildid we already have in dso->build_id (that came from the perf.data build_id section, collected at perf record time) unconditionally, even if we didn't had recorded it, and furthermore, comparing a formatted buildid with a rawbuildid, yikes. Fix it by deleting the dso__read_build_id() function, that was really misdesigned anyway, and do the necessary checks and correct comparison of raw buildids. 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: <1258582853-8579-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>