Even though with the change of commit commit 2b29175 "tools lib
traceevent: Carve out events format parsing routine", allowed
__pevent_parse_format() to parse an event without the need of a pevent
handler, the event still needs to assign the pevent handed to it.
There's no problem with assigning it if the pevent is NULL, as the
event->pevent would be NULL without the assignment. But function parsing
handlers may be assigned to the pevent handler to help in parsing the
event. If there's no pevent then there would not be any function
handlers, but if the pevent isn't assigned first before parsing the
event, it wont honor the function handlers that were assigned.
Worse yet, the current code crashes if an event has a function that it
tries to parse. For example:
# perf record -e scsi:scsi_dispatch_cmd_timeout
Segmentation fault (core dumped)
This happens because the scsi_dispatch_cmd_timeout event format has the following:
scsi_trace_parse_cdb(p, __get_dynamic_array(cmnd), REC->cmd_len)
which hasn't been defined by the pevent code.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1349136831.22822.133.camel@gandalf.local.home
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Summary of events per Peter:
"Intel PEBS in VT-x context uses the DS address as a guest linear address,
even though its programmed by the host as a host linear address. This
either results in guest memory corruption and or the hardware faulting and
'crashing' the virtual machine. Therefore we have to disable PEBS on VT-x
enter and re-enable on VT-x exit, enforcing a strict exclude_guest.
AMB IBS does work but doesn't currently support exclude_* at all,
setting an exclude_* bit will make it fail."
This patch handles userspace perf command, setting the exclude_guest
attribute if precise mode is requested, but only if a user has not
specified a request for guest or host only profiling (G or H attribute).
Kernel side AMD currently ignores all exclude_* bits, so there is no impact
to existing IBS code paths. Robert Richter has a patch where IBS code will
return EINVAL if an exclude_* bit is set. When this goes in it means use
of :p on AMD with IBS will first fail with EINVAL (because exclude_guest
will be set). Then the existing fallback code within perf will unset
exclude_guest and try again. The second attempt will succeed if the CPU
supports IBS profiling.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Robert Richter <robert.richter@amd.com>
Tested-by: Robert Richter <robert.richter@amd.com>
Reviewed-by: Robert Richter <robert.richter@amd.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <robert.richter@amd.com>
Link: http://lkml.kernel.org/r/1347569955-54626-2-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Stephane thought the perf_cpu_context::active_pmu name confusing and
suggested using 'unique_pmu' instead.
This pointer is a pointer to a 'random' pmu sharing the cpuctx
instance, therefore limiting a for_each_pmu loop to those where
cpuctx->unique_pmu matches the pmu we get a loop over unique cpuctx
instances.
Suggested-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-kxyjqpfj2fn9gt7kwu5ag9ks@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add sysfs format entries for AMD IBS PMUs:
# find /sys/bus/event_source/devices/ibs_*/format
/sys/bus/event_source/devices/ibs_fetch/format
/sys/bus/event_source/devices/ibs_fetch/format/rand_en
/sys/bus/event_source/devices/ibs_op/format
/sys/bus/event_source/devices/ibs_op/format/cnt_ctl
This allows to specify following IBS options:
$ perf record -e ibs_fetch/rand_en=1/GH ...
$ perf record -e ibs_op/cnt_ctl=1/GH ...
Option cnt_ctl is only enabled if the IBS_CAPS_OPCNT bit is set in IBS
cpuid feature flags (AMD family 10h RevC and above).
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1347447584-28405-1-git-send-email-robert.richter@amd.com
[ Added small readability improvements. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
* Remove several cases of needless global variables, on most builtins.
* Look up thread using tid instead of pid in 'perf sched'.
* Move global variables into a perf_kvm struct, from David Ahern.
* Hists refactorings, preparatory for improved 'diff' command, from Jiri Olsa.
* Hists refactorings, preparatory for event group viewieng work, from Namhyung Kim.
* Remove double negation on optional feature macro definitions, from Namhyung Kim.
* Bash auto completion improvements, now we can auto complete the tools long
options, tracepoint event names, etc, from Namhyung Kim.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently tracepoint events cannot be completed because they contain a
colon (:) character. The colon is considered as a word separator when
bash completion is done - variable COMP_WORDBREAKS contains colon - so
if a word being completed contains a colon it can be a problem.
Recent versions of bash completion provide -n switch to
_get_comp_words_by_ref and __ltrim_colon_completions functions in order
to resolve this issue. Copy the latter in case not exists.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1349328234-16995-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>