linux.git/tools/perf/util/thread.h, branch v2.6.34

perf report: Print the map table just after samples for which no map was found

2010-03-10T12:53:52+00:00

If -vv is used just the map table will be printed, -vvv will
print the symbol table too, with it we can see that we have a
bug where some samples are not being resolved to a map when we
get them in the perf.data stream, but after we have it all
processed, we can find the right map, some reordering probably
is happening.

Upcoming patches will provide ways to ask for most PERF_SAMPLE_
conditional samples to be taken for !PERF_RECORD_SAMPLE events
too, then we'll be able to ask for PERF_SAMPLE_TIME and
PERF_SAMPLE_CPU to help diagnose this.

Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1268161097-17761-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf tools: Don't use parent comm if not set at fork time

2010-02-21T16:48:24+00:00

As the parent comm then is worthless, confusing users about the
thread where the sample really happened, leading to think that
the sample happened in the parent, not where it really happened,
in the children of a thread for which a PERF_RECORD_COMM event
was not received.

Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1266627727-19715-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf symbols: Remove perf_session usage in symbols layer

2010-02-04T08:33:24+00:00

I noticed while writing the first test in 'perf regtest' that to
just test the symbol handling routines one needs to create a
perf session, that is a layer centered on a perf.data file,
events, etc, so I untied these layers.

This reduces the complexity for the users as the number of
parameters to most of the symbols and session APIs now was
reduced while not adding more state to all the map instances by
only having data that is needed to split the kernel (kallsyms
and ELF symtab sections) maps and do vmlinux relocation on the
main kernel map.

Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1265223128-11786-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf symbols: Create thread__find_addr_map from thread__find_addr_location

2010-01-16T09:58:48+00:00

Because some tools will only want to know with maps had hits,
not needing the full symbol resolution done by
thread__find_addr_location.

Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1263519930-22803-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf tools: Encode kernel module mappings in perf.data

2010-01-13T16:39:43+00:00

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 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1263396139-4798-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf session: Move kmaps to perf_session

2009-12-14T15:57:17+00:00

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 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1260741029-4430-6-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf session: Move the global threads list to perf_session

2009-12-14T15:57:16+00:00

So that we can process two perf.data files.

We still need to add a O_MMAP mode for perf_session so that we
can do all the mmap stuff in it.

Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1260741029-4430-5-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf session: Register the idle thread in perf_session__process_events

2009-12-14T15:57:15+00:00

No need for all tools to register it and then immediately call
perf_session__process_events.

Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1260741029-4430-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf symbols: Allow lookups by symbol name too

2009-12-12T06:42:11+00:00

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 
Cc: Frédéric Weisbecker 
Cc: Masami Hiramatsu 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1260564622-12392-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar

perf symbols: Rename kthreads to kmaps, using another abstraction for it

2009-12-12T06:42:09+00:00

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 
Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Eduardo Habkost 
Cc: Frédéric Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
LKML-Reference: <1260550239-5372-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar