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387960 commits

Author SHA1 Message Date
Adrian Hunter b178170a38 perf annotate: Add call target name if it is missing
The /proc/kcore file has no symbols, so the call target name does not
display.  Fix by looking up the symbol name if it is on the same map.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-14-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:36 -03:00
Adrian Hunter 484a5e7476 perf annotate: Remove nop at end of annotation
When kcore is used for annotation, symbols do not have correct sizes
because they come from kallsyms, that has only its start address, with
the end address being the next symbol's minus one.

That sometimes results in an extra nop being seen after the end of a
function.  Remove it.

Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-13-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:35 -03:00
Adrian Hunter 34f77abcb3 perf annotate: Put dso name in symbol annotation title
Currently the symbol name is displayed at the top when displaying symbol
annotation.  Add to this the dso long name.

Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-12-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:35 -03:00
Adrian Hunter bbb7f846f8 perf annotate: Allow disassembly using /proc/kcore
Annotation with /proc/kcore is possible so the logic is adjusted to
allow it.  The main difference is that /proc/kcore had no symbols so the
parsing logic needed a tweak to read jump offsets.

The other difference is that objdump cannot always read from kcore.
That seems to be a bug with objdump.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-11-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:34 -03:00
Adrian Hunter 7a77bc2c0d perf tests: Add kcore to the object code reading test
Make the "object code reading" test attempt to read from kcore.

The test uses objdump which struggles with kcore. i.e.  doesn't always
work, sometimes takes a long time.  The test has been made to work
around those issues.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-10-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:34 -03:00
Adrian Hunter 82e75d00ad perf tests: Adjust the vmlinux symtab matches kallsyms test again
The kallsyms maps now may map to kcore and the symbol values now may be
file offsets.  For comparison with vmlinux the virtual memory address is
needed which is obtained by unmapping the symbol value.

The "vmlinux symtab matches kallsyms" is adjusted accordingly.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-9-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:33 -03:00
Adrian Hunter 8e0cf965f9 perf symbols: Add support for reading from /proc/kcore
In the absence of vmlinux, perf tools uses kallsyms for symbols.  If the
user has access, now also map to /proc/kcore.

The dso data_type is now set to either DSO_BINARY_TYPE__KCORE or
DSO_BINARY_TYPE__GUEST_KCORE as approprite.

This patch breaks the "vmlinux symtab matches kallsyms" test.  That is
fixed in a following patch.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-8-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:33 -03:00
Adrian Hunter 0131c4ec79 perf tools: Make it possible to read object code from kernel modules
The new "object code reading" test shows that it is not possible to read
object code from kernel modules.  That is because the mappings do not
map to the dsos.  This patch fixes that.

This involves identifying and flagging relocatable (ELF type ET_REL)
files (e.g. kernel modules) for symbol adjustment and updating
map__rip_2objdump() accordingly.  The kmodule parameter of
dso__load_sym() is taken into use and the module map altered to map to
the dso.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-7-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:32 -03:00
Adrian Hunter d380b34830 perf tests: Adjust the vmlinux symtab matches kallsyms test
The vmlinux maps now map to the dso and the symbol values are now file
offsets.  For comparison with kallsyms the virtual memory address is
needed which is obtained by unmapping the symbol value.

The "vmlinux symtab matches kallsyms" is adjusted accordingly.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-5-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:32 -03:00
Adrian Hunter 39b12f7812 perf tools: Make it possible to read object code from vmlinux
The new "object code reading" test shows that it is not possible to read
object code from vmlinux.  That is because the mappings do not map to
the dso.  This patch fixes that.

A side-effect of changing the kernel map is that the "reloc" offset must
be taken into account.  As a result of that separate map functions for
relocation are no longer needed.

Also fixing up the maps to match the symbols no longer makes sense and
so is not done.

The vmlinux dso data_type is now set to either DSO_BINARY_TYPE__VMLINUX
or DSO_BINARY_TYPE__GUEST_VMLINUX as approprite, which enables the
correct file name to be determined by dso__binary_type_file().

This patch breaks the "vmlinux symtab matches kallsyms" test.  That is
fixed in a following patch.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:31 -03:00
Adrian Hunter 5b7ba82a75 perf symbols: Load kernel maps before using
In order to use kernel maps to read object code, those maps must be
adjusted to map to the dso file offset.  Because lazy-initialization is
used, that is not done until symbols are loaded.  However the maps are
first used by thread__find_addr_map() before symbols are loaded.  So
this patch changes thread__find_addr() to "load" kernel maps before
using them.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:31 -03:00
Adrian Hunter b55ae0a976 perf tests: Add test for reading object code
Using the information in mmap events, perf tools can read object code
associated with sampled addresses.  A test is added that compares bytes
read by perf with the same bytes read using objdump.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:30 -03:00
Adrian Hunter 3445432b7b perf symbols: avoid SyS kernel syscall aliases
When removing duplicate symbols, prefer to remove syscall aliases
starting with SyS or compat_SyS.

A side-effect of that is that it results in slightly improved results
for the "vmlinux symtab matches kallsyms" test.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:30 -03:00
Andi Kleen 2bbf03f16a perf stat: Flush output after each line in interval mode
When interval mode is outputting to a pipe, each measurement should be
flushed individually, so that the reader sees it timely.

With a terminal each line is automatically flushed by stdio, but that is
disabled with non terminal output.

Simply fflush output after each time interval

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375490473-1503-5-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:29 -03:00
Andi Kleen 411916880f perf stat: Add support for --initial-delay option
When measuring workloads the startup phase -- doing page faults, dynamic
linking, opening files -- is often very different from the rest of the
workload.  Especially with smaller kernels and using counter
multiplexing this can give significant measurement errors.

Multiplexing assumes that the workload is mostly the same over longer
periods. But at startup there is typically some spike of activity which
is relatively short.  If many groups are multiplexing the one group
seeing the spike, and which is then scaled up over the time to run all
groups, may see a significant error.

Also in general it's often not useful to measure the startup, because it
is so different from the rest.

One way around this is to use interval mode and discard the first
sample, but this can be awkward because interval mode doesn't support
intervals of less than 100ms, and also a useful interval is not
necessarily the same as a useful startup delay.

This patch adds a new --initial-delay / -D option to skip measuring for
the startup phase. The time can be specified in ms

Here's a simple example:

perf stat -e page-faults bash -c 'for i in $(seq 100000) ; do true ; done'
...
             3,721 page-faults
...

If we just wait 20 ms the number of page faults is 1/3 less:

perf stat -D 20 -e page-faults bash -c 'for i in $(seq 100000) ; do true ; done'
...
             2,823 page-faults
...

So we filtered out most of the startup noise from bash.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375490473-1503-4-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:29 -03:00
Andi Kleen e2407bef96 perf evsel: Add support for enabling counters
Add support for enabling already set up counters by using an
ioctl. I share some code with the filter setup.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375490473-1503-3-git-send-email-andi@firstfloor.org
[ Fixed up 'err' variable indentation ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:28 -03:00
Andi Kleen 5c6974f498 perf evlist: Remove obsolete dummy execve
Minor cleanup.

The dummy execve to pre-resolve the PLT is obsolete since
"enable_on_execve" was added. The counters are only
running after the execve anyways. So just remove it.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375490473-1503-2-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:28 -03:00
David Ahern 8fdd84c44f perf kvm: Split out tracepoints from record args
Needed by kvm live command. Make record_args a local while we are
messing with the args.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Runzhen Wang <runzhen@linux.vnet.ibm.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1375473947-64285-5-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:27 -03:00
David Ahern 9c5014022f perf session: Export a few functions for event processing
Allows kvm live mode to reuse the event processing and ordered samples
processing used by the perf-report path.

v2: removed flush_sample_queue as noticed by Jiri

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Runzhen Wang <runzhen@linux.vnet.ibm.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1375473947-64285-4-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:27 -03:00
David Ahern ffe4f3c0d1 perf stats: Add max and min stats
Need an initialization function to set min to -1 to
differentiate from an actual min of 0.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Runzhen Wang <runzhen@linux.vnet.ibm.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1375473947-64285-3-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:26 -03:00
David Ahern 42ee8c61cb perf top: move CONSOLE_CLEAR to header file
For use with kvm-live mode.

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Runzhen Wang <runzhen@linux.vnet.ibm.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1375473947-64285-2-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:26 -03:00
Namhyung Kim 3b47abe1b5 perf util: Add parse_nsec_time() function
The parse_nsec_time() function is for parsing a string of time into
64-bit nsec value.  It's a preparation of time filtering in some of perf
commands.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: David Ahern <dsahern@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1370310629-9642-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:26 -03:00
Arnaldo Carvalho de Melo 3223565cdf perf python: Remove duplicate TID bit from mask
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thiago Peixoto <thiagolcpeixoto@gmail.com>
Link: http://lkml.kernel.org/n/tip-jurgz6myq125o1ql6lldh6f7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:25 -03:00
Arnaldo Carvalho de Melo a14bb860a3 perf trace: Beautify 'connect' result
It is an errno, so print an error string.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-zt68gijvvoe8gd7kmclo43si@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:25 -03:00
David Ahern 602bab1b88 perf tools: Fix compile of util/tsc.c
On Fedora 18, with gcc 4.6.4 compile fails with:

arch/x86/util/tsc.c: In function ‘perf_time_to_tsc’:
arch/x86/util/tsc.c:13:6: error: declaration of ‘time’ shadows a global declaration [-Werror=shadow]
cc1: all warnings being treated as errors
make: *** [/tmp/junk/arch/x86/util/tsc.o] Error 1
make: *** Waiting for unfinished jobs....

Fix by renaming the local variable.

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Link: http://lkml.kernel.org/r/1374848843-43127-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:24 -03:00
David Ahern 251f426fdd perf evsel: Actually show symbol offset in stack trace when requested
Symbol offset is one of the fields that can be requested in perf-script.
Currently you do not get that data when requested. e.g.,

perf script -f comm,tid,pid,time,cpu,sym,symoff,ip
...
gcc  6201/6201  [006] 762250.617897:
    ffffffff81090d95 update_curr
    ffffffff810911b8 dequeue_entity
    ffffffff81091825 dequeue_task_fair
    ffffffff81087163 dequeue_task
    ffffffff81087c03 deactivate_task
...

With this patch you get the offset:
...
gcc  6201/6201  [006] 762250.617897:
    ffffffff81090d95 update_curr+0x1c5
    ffffffff810911b8 dequeue_entity+0x28
    ffffffff81091825 dequeue_task_fair+0x45
    ffffffff81087163 dequeue_task+0x93
    ffffffff81087c03 deactivate_task+0x23
...

Signed-off-by: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1375024474-45726-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:24 -03:00
Jiri Olsa a9f93f9742 perf tests: Add parse events tests for leader sampling
Adding 2 more tests to the automated parse events suite for following
event config:

  '{cycles,cache-misses,branch-misses}:S'
  '{instructions,branch-misses}:Su'

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-tmcy0ir7i8id2t54qg5ifbio@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:23 -03:00
Jiri Olsa 8404db6346 perf tests: Add attr record group sampling test
Adding test to validate perf_event_attr data for command:

  'record -e '{cycles,cache-misses}:S'

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-9eppxvhkly6gse5ximudckrp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:23 -03:00
Jiri Olsa 3c1763115b perf tools: Add 'S' event/group modifier to read sample value
Adding 'S' event/group modifier to specify that the event value/s are
read by PERF_SAMPLE_READ sample type processing, instead of the period
value offered by lower layers.

There's additional behaviour change for 'S' modifier being specified on
event group:

Currently all the events within a group makes samples. If user now
specifies 'S' within group modifier, only the leader will trigger
samples. The rest of events in the group will have sampling disabled.

And same as for single events, values of all events within the group
(including leader) are read by PERF_SAMPLE_READ sample type processing.

Following example will create event group with cycles and cache-misses
events, setting the cycles as group leader and the only event to
actually sample. Both cycles and cache-misses event period values are
read by PERF_SAMPLE_READ sample type processing with PERF_FORMAT_GROUP
read format.

Example:

  $ perf record -e '{cycles,cache-misses}:S' ls
  ...
  $ perf report --group --show-total-period --stdio
  ...
  # Samples: 36  of event 'anon group { cycles, cache-misses }'
  # Event count (approx.): 12585593
  #
  #       Overhead          Period  Command      Shared Object                      Symbol
  # ..............  ..............  .......  .................  ..........................
  #
    19.92%   1.20%  2505936     31       ls  [kernel.kallsyms]  [k] mark_held_locks
    13.74%   0.47%  1729327     12       ls  [kernel.kallsyms]  [k] sched_clock_local
    13.64%  23.72%  1716147    612       ls  ld-2.14.90.so      [.] check_match.10805
    13.12%  23.22%  1650778    599       ls  libc-2.14.90.so    [.] _nl_intern_locale_data
    11.24%  29.19%  1414554    753       ls  [kernel.kallsyms]  [k] sched_clock_cpu
     8.50%   0.35%  1070150      9       ls  [kernel.kallsyms]  [k] check_chain_key
  ...

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-iyoinu3axi11mymwnh2b7fxj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:22 -03:00
Jiri Olsa e4caec0d1a perf evsel: Add PERF_SAMPLE_READ sample related processing
For sample with sample type PERF_SAMPLE_READ the period value is stored
in the 'struct sample_read'.

Moreover if the read format has PERF_FORMAT_GROUP, the 'struct
sample_read' contains period values for all events in the group (for
which the sample's event is a leader).

We deliver separated samples for all the values contained within the
'struct sample_read'.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-6mdm5xkrm6kypouh1c33cyys@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:22 -03:00
Jiri Olsa 932a35940a perf evlist: Add perf_evlist__id2sid method to get event ID related data
This will be helpful for PERF_FORMAT_GROUP samples where we need to
store ID related period value for each event.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-twmlgsbyim97p7cyohjwb1df@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:21 -03:00
Jiri Olsa c4861afe30 perf evlist: Fix event ID retrieval for group format read case
We need to fail the event ID retrieval in case both following conditions
are true:

  - we are on kernel with no PERF_EVENT_IOC_ID support
  - PERF_FORMAT_GROUP read format is set

The PERF_FORMAT_GROUP read format bit is the killer for retrieving event
ID out of the read syscall, because we have no guarantee of the event
placement within leader kernel sibling list.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-e93pgyj20rqx48qzw10vj4r4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:21 -03:00
Jiri Olsa 9ede473cc9 perf tools: Add support for parsing PERF_SAMPLE_READ sample type
Adding support to parse out the PERF_SAMPLE_READ sample bits.  The code
contains both single and group format specification.

This code parse out and prepare PERF_SAMPLE_READ data into the
perf_sample struct. It will be used for group leader sampling feature
comming in shortly.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-0tgdoln5rwk3wocshb442cl3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:20 -03:00
Jiri Olsa e2b5abe0c8 perf evlist: Use PERF_EVENT_IOC_ID perf ioctl to read event id
Changing the way we retrieve the event ID. Instead of parsing out
the ID out of the read data, using the PERF_EVENT_IOC_ID ioctl.

Keeping the old way in place to support kernels without
PERF_EVENT_IOC_ID ioctl support.

This will be useful for retrieving the event ID for events
with PERF_FORMAT_GROUP read format set, where it's impossible
to get correct event id out of the read call data.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-psgb4n7kte8e6tfenbe7nj2h@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:20 -03:00
Jiri Olsa 6f5ab0019f perf: Do not get values from disabled counters in group format read
It's possible some of the counters in the group could be
disabled when sampling member of the event group is reading
the rest via PERF_SAMPLE_READ sample type processing. Disabled
counters could then produce wrong numbers.

Fixing that by reading only enabled counters for PERF_SAMPLE_READ
sample type processing.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-wwkjb0bbcuslnz0klrmqi26r@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:19 -03:00
Jiri Olsa cf4957f17f perf: Add PERF_EVENT_IOC_ID ioctl to return event ID
The only way to get the event ID is by reading the event fd,
followed by parsing the ID value out of the returned data.

While this is ok for current read format used by perf tool,
it is not ok when we use PERF_FORMAT_GROUP format.

With this format the data are returned for the whole group
and there's no way to find out what ID belongs to our fd
(if we are not group leader event).

Adding a simple ioctl that returns event primary ID for given fd.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-v1bn5cto707jn0bon34afqr1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:19 -03:00
Frederic Weisbecker 93786a5f6a watchdog: Make it work under full dynticks
A perf event can be used without forcing the tick to
stay alive if it doesn't use a frequency but a sample
period and if it doesn't throttle (raise storm of events).

Since the lockup detector neither use a perf event frequency
nor should ever throttle due to its high period, it can now
run concurrently with the full dynticks feature.

So remove the hack that disabled the watchdog.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Anish Singh <anish198519851985@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1374539466-4799-9-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-30 22:29:15 +02:00
Frederic Weisbecker d84153d6c9 perf: Implement finer grained full dynticks kick
Currently the full dynticks subsystem keep the
tick alive as long as there are perf events running.

This prevents the tick from being stopped as long as features
such that the lockup detectors are running. As a temporary fix,
the lockup detector is disabled by default when full dynticks
is built but this is not a long term viable solution.

To fix this, only keep the tick alive when an event configured
with a frequency rather than a period is running on the CPU,
or when an event throttles on the CPU.

These are the only purposes of the perf tick, especially now that
the rotation of flexible events is handled from a seperate hrtimer.
The tick can be shutdown the rest of the time.

Original-patch-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1374539466-4799-8-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-30 22:29:15 +02:00
Frederic Weisbecker ba8a75c16e perf: Account freq events per cpu
This is going to be used by the full dynticks subsystem
as a finer-grained information to know when to keep and
when to stop the tick.

Original-patch-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1374539466-4799-7-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-30 22:29:14 +02:00
Frederic Weisbecker 9a545de019 perf: Migrate per cpu event accounting
When an event is migrated, move the event per-cpu
accounting accordingly so that branch stack and cgroup
events work correctly on the new CPU.

Original-patch-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1374539466-4799-6-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-30 22:29:14 +02:00
Frederic Weisbecker 4beb31f365 perf: Split the per-cpu accounting part of the event accounting code
This way we can use the per-cpu handling seperately.
This is going to be used by to fix the event migration
code accounting.

Original-patch-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1374539466-4799-5-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-30 22:29:13 +02:00
Frederic Weisbecker 766d6c0769 perf: Factor out event accounting code to account_event()/__free_event()
Gather all the event accounting code to a single place,
once all the prerequisites are completed. This simplifies
the refcounting.

Original-patch-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1374539466-4799-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-30 22:29:12 +02:00
Frederic Weisbecker 90983b1607 perf: Sanitize get_callchain_buffer()
In case of allocation failure, get_callchain_buffer() keeps the
refcount incremented for the current event.

As a result, when get_callchain_buffers() returns an error,
we must cleanup what it did by cancelling its last refcount
with a call to put_callchain_buffers().

This is a hack in order to be able to call free_event()
after that failure.

The original purpose of that was to simplify the failure
path. But this error handling is actually counter intuitive,
ugly and not very easy to follow because one expect to
see the resources used to perform a service to be cleaned
by the callee if case of failure, not by the caller.

So lets clean this up by cancelling the refcount from
get_callchain_buffer() in case of failure. And correctly free
the event accordingly in perf_event_alloc().

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1374539466-4799-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-30 22:29:12 +02:00
Frederic Weisbecker 6050cb0b0b perf: Fix branch stack refcount leak on callchain init failure
On callchain buffers allocation failure, free_event() is
called and all the accounting performed in perf_event_alloc()
for that event is cancelled.

But if the event has branch stack sampling, it is unaccounted
as well from the branch stack sampling events refcounts.

This is a bug because this accounting is performed after the
callchain buffer allocation. As a result, the branch stack sampling
events refcount can become negative.

To fix this, move the branch stack event accounting before the
callchain buffer allocation.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1374539466-4799-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-30 22:22:58 +02:00
Peter Zijlstra 7d9ffa8961 sched: Micro-optimize the smart wake-affine logic
Smart wake-affine is using node-size as the factor currently, but the overhead
of the mask operation is high.

Thus, this patch introduce the 'sd_llc_size' percpu variable, which will record
the highest cache-share domain size, and make it to be the new factor, in order
to reduce the overhead and make it more reasonable.

Tested-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Tested-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Link: http://lkml.kernel.org/r/51D5008E.6030102@linux.vnet.ibm.com
[ Tidied up the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-23 12:22:06 +02:00
Michael Wang 62470419e9 sched: Implement smarter wake-affine logic
The wake-affine scheduler feature is currently always trying to pull
the wakee close to the waker. In theory this should be beneficial if
the waker's CPU caches hot data for the wakee, and it's also beneficial
in the extreme ping-pong high context switch rate case.

Testing shows it can benefit hackbench up to 15%.

However, the feature is somewhat blind, from which some workloads
such as pgbench suffer. It's also time-consuming algorithmically.

Testing shows it can damage pgbench up to 50% - far more than the
benefit it brings in the best case.

So wake-affine should be smarter and it should realize when to
stop its thankless effort at trying to find a suitable CPU to wake on.

This patch introduces 'wakee_flips', which will be increased each
time the task flips (switches) its wakee target.

So a high 'wakee_flips' value means the task has more than one
wakee, and the bigger the number, the higher the wakeup frequency.

Now when making the decision on whether to pull or not, pay attention to
the wakee with a high 'wakee_flips', pulling such a task may benefit
the wakee. Also imply that the waker will face cruel competition later,
it could be very cruel or very fast depends on the story behind
'wakee_flips', waker therefore suffers.

Furthermore, if waker also has a high 'wakee_flips', that implies that
multiple tasks rely on it, then waker's higher latency will damage all
of them, so pulling wakee seems to be a bad deal.

Thus, when 'waker->wakee_flips / wakee->wakee_flips' becomes
higher and higher, the cost of pulling seems to be worse and worse.

The patch therefore helps the wake-affine feature to stop its pulling
work when:

	wakee->wakee_flips > factor &&
	waker->wakee_flips > (factor * wakee->wakee_flips)

The 'factor' here is the number of CPUs in the current CPU's NUMA node,
so a bigger node will lead to more pulling since the trial becomes more
severe.

After applying the patch, pgbench shows up to 40% improvements and no regressions.

Tested with 12 cpu x86 server and tip 3.10.0-rc7.

The percentages in the final column highlight the areas with the biggest wins,
all other areas improved as well:

	pgbench		    base	smart

	| db_size | clients |  tps  |	|  tps  |
	+---------+---------+-------+   +-------+
	| 22 MB   |       1 | 10598 |   | 10796 |
	| 22 MB   |       2 | 21257 |   | 21336 |
	| 22 MB   |       4 | 41386 |   | 41622 |
	| 22 MB   |       8 | 51253 |   | 57932 |
	| 22 MB   |      12 | 48570 |   | 54000 |
	| 22 MB   |      16 | 46748 |   | 55982 | +19.75%
	| 22 MB   |      24 | 44346 |   | 55847 | +25.93%
	| 22 MB   |      32 | 43460 |   | 54614 | +25.66%
	| 7484 MB |       1 |  8951 |   |  9193 |
	| 7484 MB |       2 | 19233 |   | 19240 |
	| 7484 MB |       4 | 37239 |   | 37302 |
	| 7484 MB |       8 | 46087 |   | 50018 |
	| 7484 MB |      12 | 42054 |   | 48763 |
	| 7484 MB |      16 | 40765 |   | 51633 | +26.66%
	| 7484 MB |      24 | 37651 |   | 52377 | +39.11%
	| 7484 MB |      32 | 37056 |   | 51108 | +37.92%
	| 15 GB   |       1 |  8845 |   |  9104 |
	| 15 GB   |       2 | 19094 |   | 19162 |
	| 15 GB   |       4 | 36979 |   | 36983 |
	| 15 GB   |       8 | 46087 |   | 49977 |
	| 15 GB   |      12 | 41901 |   | 48591 |
	| 15 GB   |      16 | 40147 |   | 50651 | +26.16%
	| 15 GB   |      24 | 37250 |   | 52365 | +40.58%
	| 15 GB   |      32 | 36470 |   | 50015 | +37.14%

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/51D50057.9000809@linux.vnet.ibm.com
[ Improved the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-23 12:18:41 +02:00
Vladimir Davydov 685207963b sched: Move h_load calculation to task_h_load()
The bad thing about update_h_load(), which computes hierarchical load
factor for task groups, is that it is called for each task group in the
system before every load balancer run, and since rebalance can be
triggered very often, this function can eat really a lot of cpu time if
there are many cpu cgroups in the system.

Although the situation was improved significantly by commit a35b646
('sched, cgroup: Reduce rq->lock hold times for large cgroup
hierarchies'), the problem still can arise under some kinds of loads,
e.g. when cpus are switching from idle to busy and back very frequently.

For instance, when I start 1000 of processes that wake up every
millisecond on my 8 cpus host, 'top' and 'perf top' show:

Cpu(s): 17.8%us, 24.3%sy,  0.0%ni, 57.9%id,  0.0%wa,  0.0%hi,  0.0%si
Events: 243K cycles
  7.57%  [kernel]               [k] __schedule
  7.08%  [kernel]               [k] timerqueue_add
  6.13%  libc-2.12.so           [.] usleep

Then if I create 10000 *idle* cpu cgroups (no processes in them), cpu
usage increases significantly although the 'wakers' are still executing
in the root cpu cgroup:

Cpu(s): 19.1%us, 48.7%sy,  0.0%ni, 31.6%id,  0.0%wa,  0.0%hi,  0.7%si
Events: 230K cycles
 24.56%  [kernel]            [k] tg_load_down
  5.76%  [kernel]            [k] __schedule

This happens because this particular kind of load triggers 'new idle'
rebalance very frequently, which requires calling update_h_load(),
which, in turn, calls tg_load_down() for every *idle* cpu cgroup even
though it is absolutely useless, because idle cpu cgroups have no tasks
to pull.

This patch tries to improve the situation by making h_load calculation
proceed only when h_load is really necessary. To achieve this, it
substitutes update_h_load() with update_cfs_rq_h_load(), which computes
h_load only for a given cfs_rq and all its ascendants, and makes the
load balancer call this function whenever it considers if a task should
be pulled, i.e. it moves h_load calculations directly to task_h_load().
For h_load of the same cfs_rq not to be updated multiple times (in case
several tasks in the same cgroup are considered during the same balance
run), the patch keeps the time of the last h_load update for each cfs_rq
and breaks calculation when it finds h_load to be uptodate.

The benefit of it is that h_load is computed only for those cfs_rq's,
which really need it, in particular all idle task groups are skipped.
Although this, in fact, moves h_load calculation under rq lock, it
should not affect latency much, because the amount of work done under rq
lock while trying to pull tasks is limited by sched_nr_migrate.

After the patch applied with the setup described above (1000 wakers in
the root cgroup and 10000 idle cgroups), I get:

Cpu(s): 16.9%us, 24.8%sy,  0.0%ni, 58.4%id,  0.0%wa,  0.0%hi,  0.0%si
Events: 242K cycles
  7.57%  [kernel]                  [k] __schedule
  6.70%  [kernel]                  [k] timerqueue_add
  5.93%  libc-2.12.so              [.] usleep

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1373896159-1278-1-git-send-email-vdavydov@parallels.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-23 12:18:41 +02:00
Adrian Hunter 3bd5a5fc8c perf tools: Add test for converting perf time to/from TSC
The test uses the newly added cap_usr_time_zero and time_zero of
perf_event_mmap_page.  TSC from rdtsc is compared with the time
from 2 perf events.  The test passes if the calculated times are
all in the correct order.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1372425741-1676-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-23 12:17:59 +02:00
Adrian Hunter c73deb6aec perf/x86: Add ability to calculate TSC from perf sample timestamps
For modern CPUs, perf clock is directly related to TSC.  TSC
can be calculated from perf clock and vice versa using a simple
calculation.  Two of the three componenets of that calculation
are already exported in struct perf_event_mmap_page.  This patch
exports the third.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1372425741-1676-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-23 12:17:45 +02:00
Adrian Hunter 860f085b74 perf: Fix broken union in 'struct perf_event_mmap_page'
The capabilities bits must not be "union'ed" together.
Put them in a separate struct.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1372425741-1676-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-23 12:17:10 +02:00