uprobes/tracing: Don't pass addr=ip to perf_trace_buf_submit()
uprobe_perf_print() passes addr=ip to perf_trace_buf_submit() for
no reason. This sets perf_sample_data->addr for PERF_SAMPLE_ADDR,
we already have perf_sample_data->ip initialized if PERF_SAMPLE_IP.
Oleg Nesterov [Sat, 30 Mar 2013 17:46:22 +0000 (18:46 +0100)]
uprobes/tracing: Make uprobe_{trace,perf}_print() uretprobe-friendly
Change uprobe_trace_print() and uprobe_perf_print() to check
is_ret_probe() and fill ring_buffer_event accordingly.
Also change uprobe_trace_func() and uprobe_perf_func() to not
_print() if is_ret_probe() is true. Note that we keep ->handler()
nontrivial even for uretprobe, we need this for filtering and for
other potential extensions.
Oleg Nesterov [Sat, 30 Mar 2013 17:25:23 +0000 (18:25 +0100)]
uprobes/tracing: Introduce is_ret_probe() and uretprobe_dispatcher()
Create the new functions we need to support uretprobes, and change
alloc_trace_uprobe() to initialize consumer.ret_handler if the new
"is_ret" argument is true. Curently this argument is always false,
so the new code is never called and is_ret_probe(tu) is false too.
Extract the output code from uprobe_trace_func() and uprobe_perf_func()
into the new helpers, they will be used by ->ret_handler() too. We also
add the unused "unsigned long func" argument in advance, to simplify the
next changes.
struct uprobe_trace_entry_head has a single member for reporting,
"unsigned long ip". If we want to support uretprobes we need to
create another struct which has "func" and "ret_ip" and duplicate
a lot of functions, like trace_kprobe.c does.
To avoid this copy-and-paste horror we turn ->ip into ->vaddr[]
and add couple of trivial helpers to calculate sizeof/data. This
uglifies the code a bit, but this allows us to avoid a lot more
complications later, when we add the support for ret-probes.
Anton Arapov [Wed, 3 Apr 2013 16:00:37 +0000 (18:00 +0200)]
uretprobes: Limit the depth of return probe nestedness
Unlike the kretprobes we can't trust userspace, thus must have
protection from user space attacks. User-space have "unlimited"
stack, and this patch limits the return probes nestedness as a
simple remedy for it.
Note that this implementation leaks return_instance on siglongjmp
until exit()/exec().
The intention is to have KISS and bare minimum solution for the
initial implementation in order to not complicate the uretprobes
code.
In the future we may come up with more sophisticated solution that
remove this depth limitation. It is not easy task and lays beyond
this patchset.
Anton Arapov [Wed, 3 Apr 2013 16:00:36 +0000 (18:00 +0200)]
uretprobes: Return probe exit, invoke handlers
Uretprobe handlers are invoked when the trampoline is hit, on completion
the trampoline is replaced with the saved return address and the uretprobe
instance deleted.
TODO: handle_trampoline() assumes that ->return_instances is always valid.
We should teach it to handle longjmp() which can invalidate the pending
return_instance's. This is nontrivial, we will try to do this in a separate
series.
When a uprobe with return probe consumer is hit, prepare_uretprobe()
function is invoked. It creates return_instance, hijacks return address
and replaces it with the trampoline.
* Return instances are kept as stack per uprobed task.
* Return instance is chained, when the original return address is
trampoline's page vaddr (e.g. recursive call of the probed function).
Anton Arapov [Wed, 3 Apr 2013 16:00:32 +0000 (18:00 +0200)]
uretprobes: Reserve the first slot in xol_vma for trampoline
Allocate trampoline page, as the very first one in uprobed
task xol area, and fill it with breakpoint opcode.
Also introduce get_trampoline_vaddr() helper, to wrap the
trampoline address extraction from area->vaddr. That removes
confusion and eases the debug experience in case ->vaddr
notion will be changed.
Enclose return probes implementation, introduce ->ret_handler() and update
existing code to rely on ->handler() *and* ->ret_handler() for uprobe and
uretprobe respectively.
uprobes/powerpc: Teach uprobes to ignore gdb breakpoints
Powerpc has many trap variants that could be used by entities like gdb.
Currently, running gdb on a program being traced by uprobes causes an
endless loop since uprobes doesn't understand that the trap was inserted
by some other entity and a SIGTRAP needs to be delivered.
Teach uprobes to ignore breakpoints that do not belong to it.
Some architectures like powerpc have multiple variants of the trap
instruction. Introduce an additional helper is_trap_insn() for run-time
handling of non-uprobe traps on such architectures.
While there, change is_swbp_at_addr() to is_trap_at_addr() for reading
clarity.
With this change, the uprobe registration path will supercede any trap
instruction inserted at the requested location, while taking care of
delivering the SIGTRAP for cases where the trap notification came in
for an address without a uprobe. See [1] for a more detailed explanation.
Oleg Nesterov [Sun, 17 Mar 2013 17:54:44 +0000 (18:54 +0100)]
uprobes: Use file_inode()
Cleanup. Now that we have f_inode/file_inode() we can use it instead
of vm_file->f_mapping->host.
This should not make any difference for uprobes, but in theory this
change is more correct. We use this inode as a key, to compare it
with uprobe->inode set by uprobe_register(inode), and the caller uses
d_inode.
perf map browser: Exit just on well known key presses
Initial motivation was to avoid the confusing exit when when '/' is
pressed in non verbose mode, as specified in the help line searches
are only available in verbose mode.
Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> 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/n/tip-20xezxim2y4agmkx7f3sucll@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now that the map browser shares the input routine with the hists
browser, there is no need for using any libnewt routine, so remove all
traces except for honouring NO_NEWT=1 on the makefile command line as an
indication that TUI support is not needed, in fact it just sets
NO_SLANG=1.
Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> 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/n/tip-wae5o7xca9m52bj1re28jc5j@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Naohiro Aota [Sun, 24 Mar 2013 13:37:54 +0000 (22:37 +0900)]
perf python: Fix dependency for python/perf.so
The python/perf.so binding lacks dependency for libtraceevent.a so that
it cause the following error building python/perf.so. This patch
introduce the dependency for it.
$ make python/perf.so
CHK -fstack-protector-all
CHK -Wstack-protector
CHK -Wvolatile-register-var
CHK -D_FORTIFY_SOURCE=2
CHK bionic
CHK libelf
CHK libdw
CHK libunwind
CHK -DLIBELF_MMAP
CHK libaudit
CHK libnewt
CHK gtk2
CHK -DHAVE_GTK_INFO_BAR
CHK perl
CHK python
CHK python version
CHK libbfd
CHK -DHAVE_STRLCPY
CHK -DHAVE_ON_EXIT
CHK -DBACKTRACE_SUPPORT
CHK libnuma
GEN python/perf.so
x86_64-pc-linux-gnu-gcc: error: ../lib/traceevent/libtraceevent.a: No such file or directory
error: command 'x86_64-pc-linux-gnu-gcc' failed with exit status 1
cp: cannot stat 'python_ext_build/lib/perf.so': No such file or directory
make: *** [python/perf.so] Error 1
[root@sandy linux]# perf sched rec
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.306 MB perf.data (~57062 samples) ]
perf
[root@sandy linux]# perf sched lat
perf: builtin-sched.c:781: thread_atoms_search: Assertion `!(thread != atoms->thread)' failed.
Aborted (core dumped)
[root@sandy linux]#
Further investigation is needed to check that even with machine__remove_thread()
not really deleting the thread referenced in the PERF_RECORD_EXIT (it goes to
machine->dead_threads, because references may still exist to them in things like
hist, etc) some event later comes for this dead thread and then
machine__findnew_thread() will create a new thead instance that will not be the
same as the one referenced by work_atoms->thread in thread_atoms_search().
For now just revert this patch to get the 'perf sched lat' back working.
Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> 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/n/tip-`ranpwd Link: http://lkml.kernel.org/n/tip-hg4s6e5txiwqe00h8rdg1sin@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Thu, 24 Jan 2013 15:10:42 +0000 (16:10 +0100)]
perf tools: Fix output of symbol_daddr offset
The symbol addresses in a dso have relative offsets from the start of a
mapping. So in order to ouput correct offset value from @ip, one of
them should be converted.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1359040242-8269-19-git-send-email-eranian@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Stephane Eranian [Thu, 24 Jan 2013 15:10:35 +0000 (16:10 +0100)]
perf tools: Add mem access sampling core support
This patch adds the sorting and histogram support
functions to enable profiling of memory accesses.
The following sorting orders are added:
- symbol_daddr: data address symbol (or raw address)
- dso_daddr: data address shared object
- locked: access uses locked transaction
- tlb : TLB access
- mem : memory level of the access (L1, L2, L3, RAM, ...)
- snoop: access snoop mode
Signed-off-by: Stephane Eranian <eranian@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1359040242-8269-12-git-send-email-eranian@google.com
[ committer note: changed to cope with fc5871ed, the move of methods to
machine.[ch], and the rename of dsrc to data_src, to match the change
made in the PERF_SAMPLE_DSRC in a previous patch. ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Andi Kleen [Thu, 24 Jan 2013 15:10:29 +0000 (16:10 +0100)]
perf tools: Add support for weight v7 (modified)
perf record has a new option -W that enables weightened sampling.
Add sorting support in top/report for the average weight per sample and the
total weight sum. This allows to both compare relative cost per event
and the total cost over the measurement period.
Add the necessary glue to perf report, record and the library.
v2: Merge with new hist refactoring.
v3: Fix manpage. Remove value check.
Rename global_weight to weight and weight to local_weight.
v4: Readd sort keys to manpage
v5: Move weight to end
v6: Move weight to template
v7: Rename weight key.
Original patch from Andi modified by Stephane Eranian <eranian@google.com>
to include ONLY the weight supporting code and apply to pristine 3.8.0-rc4.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1359040242-8269-6-git-send-email-eranian@google.com
[ committer note: changed to cope with fc5871ed and the hists_link perf test entry ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Stephane Eranian [Thu, 24 Jan 2013 15:10:39 +0000 (16:10 +0100)]
perf: Add PERF_RECORD_MISC_MMAP_DATA to RECORD_MMAP
Type of mapping was lost and made it hard for a tool
to distinguish code vs. data mmaps. Perf has the ability
to distinguish the two.
Use a bit in the header->misc bitmask to keep track of
the mmap type. If PERF_RECORD_MISC_MMAP_DATA is set then
the mapping is not executable (!VM_EXEC). If not set, then
the mapping is executable.
Stephane Eranian [Thu, 24 Jan 2013 15:10:34 +0000 (16:10 +0100)]
perf/x86: Add support for PEBS Precise Store
This patch adds support for PEBS Precise Store
which is available on Intel Sandy Bridge and
Ivy Bridge processors.
To use Precise store, the proper PEBS event
must be used: mem_trans_retired:precise_stores.
For the perf tool, the generic mem-stores event
exported via sysfs can be used directly.
Stephane Eranian [Thu, 24 Jan 2013 15:10:32 +0000 (16:10 +0100)]
perf/x86: Add memory profiling via PEBS Load Latency
This patch adds support for memory profiling using the
PEBS Load Latency facility.
Load accesses are sampled by HW and the instruction
address, data address, load latency, data source, tlb,
locked information can be saved in the sampling buffer
if using the PERF_SAMPLE_COST (for latency),
PERF_SAMPLE_ADDR, PERF_SAMPLE_DATA_SRC types.
To enable PEBS Load Latency, users have to use the
model specific event:
- on NHM/WSM: MEM_INST_RETIRED:LATENCY_ABOVE_THRESHOLD
- on SNB/IVB: MEM_TRANS_RETIRED:LATENCY_ABOVE_THRESHOLD
To make things easier, this patch also exports a generic
alias via sysfs: mem-loads. It export the right event
encoding based on the host CPU and can be used directly
by the perf tool.
Loosely based on Intel's Lin Ming patch posted on LKML
in July 2011.
Stephane Eranian [Thu, 24 Jan 2013 15:10:31 +0000 (16:10 +0100)]
perf: Add generic memory sampling interface
This patch adds PERF_SAMPLE_DATA_SRC.
PERF_SAMPLE_DATA_SRC collects the data source, i.e., where
did the data associated with the sampled instruction
come from. Information is stored in a perf_mem_data_src
structure. It contains opcode, mem level, tlb, snoop,
lock information, subject to availability in hardware.
Andi Kleen [Thu, 24 Jan 2013 15:10:28 +0000 (16:10 +0100)]
perf/core: Add weighted samples
For some events it's useful to weight sample with a hardware
provided number. This expresses how expensive the action the
sample represent was. This allows the profiler to scale
the samples to be more informative to the programmer.
There is already the period which is used similarly, but it
means something different, so I chose to not overload it.
Instead a new sample type for WEIGHT is added.
Can be used for multiple things. Initially it is used for TSX
abort costs and profiling by memory latencies (so to make
expensive load appear higher up in the histograms). The concept
is quite generic and can be extended to many other kinds of
events or architectures, as long as the hardware provides
suitable auxillary values. In principle it could be also used
for software tracepoints.
This adds the generic glue. A new optional sample format for a
64-bit weight value.
Stephane Eranian [Thu, 24 Jan 2013 15:10:27 +0000 (16:10 +0100)]
perf/x86: Add flags to event constraints
This patch adds a flags field to each event constraint.
It can be used to store event specific features which can
then later be used by scheduling code or low-level x86 code.
The flags are propagated into event->hw.flags during the
get_event_constraint() call. They are cleared during the
put_event_constraint() call.
This mechanism is going to be used by the PEBS-LL patches.
It avoids defining yet another table to hold event specific
information.
Stephane Eranian [Thu, 24 Jan 2013 15:10:26 +0000 (16:10 +0100)]
perf/x86: Improve sysfs event mapping with event string
This patch extends Jiri's changes to make generic
events mapping visible via sysfs. The patch extends
the mechanism to non-generic events by allowing
the mappings to be hardcoded in strings.
This mechanism will be used by the PEBS-LL patch
later on.
Signed-off-by: Stephane Eranian <eranian@google.com> Cc: peterz@infradead.org Cc: ak@linux.intel.com Cc: acme@redhat.com Cc: jolsa@redhat.com Cc: namhyung.kim@lge.com Link: http://lkml.kernel.org/r/1359040242-8269-3-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
[ fixed up conflict with 2663960 "perf: Make EVENT_ATTR global" ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Stephane Eranian [Thu, 14 Feb 2013 12:57:29 +0000 (13:57 +0100)]
perf stat: Add per-core aggregation
This patch adds the --per-core option to perf stat.
This option is used to aggregate system-wide counts
on a per physical core basis. On processors with
hyperthreading, this means counts of all HT threads
running on a physical core are aggregated.
This mode is useful to find imblance between physical
cores running an uniform workload. Cores are identified
by socket: S0-C1, means physical core 1 on socket 0. Note
that cores are identified using their physical core id,
thus their numbering may not be continuous.
Per core aggregation can be combined with interval printing:
Namhyung Kim [Thu, 21 Mar 2013 07:18:52 +0000 (16:18 +0900)]
perf tools: Cleanup calc_data_size logic
It's for calculating whole trace data size during reading. However
relation functions are called only in this file, no need to
conditionalize it with tricky +1 offset and rename the variable to
more meaningful name like trace_data_size.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> 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> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1363850332-25297-10-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Thu, 21 Mar 2013 07:18:48 +0000 (16:18 +0900)]
perf tools: Handle failure case in trace_report()
If pevent allocation in read_trace_init() fails, trace_report() will
return -1 and *ppevent is set to NULL. Its callers should check this
case and handle it properly.
This is also a preparation for the removal of *die() calls.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> 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> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1363850332-25297-6-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Mon, 18 Mar 2013 02:41:47 +0000 (11:41 +0900)]
perf tests: Add a test case for checking sw clock event frequency
This test case checks frequency conversion of hrtimer-based software
clock events (cpu-clock, task-clock) have valid (non-1) periods.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1363574507-18808-2-git-send-email-namhyung@kernel.org
[ committer note: Moved .sample_freq to outside named init block to cope with some gcc versions ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Stephane Eranian [Sun, 17 Mar 2013 13:49:57 +0000 (14:49 +0100)]
perf/x86: Add SNB/SNB-EP scheduling constraints for cycle_activity event
Add scheduling constraints for SNB/SNB-EP CYCLE_ACTIVITY event
as defined by SDM Jan 2013 edition. The STALLS umasks are
combinations with the NO_DISPATCH umask.
Masami Hiramatsu [Thu, 14 Mar 2013 11:52:43 +0000 (20:52 +0900)]
kprobes/x86: Check Interrupt Flag modifier when registering probe
Currently kprobes check whether the copied instruction modifies
IF (interrupt flag) on each probe hit. This results not only in
introducing overhead but also involving
inat_get_opcode_attribute into the kprobes hot path, and it can
cause an infinite recursive call (and kernel panic in the end).
Actually, since the copied instruction itself can never be modified
on the buffer, it is needless to analyze the instruction on every
probe hit.
To fix this issue, we check it only once when registering probe
and store the result on ainsn->if_modifier.
Reported-by: Timo Juhani Lindfors <timo.lindfors@iki.fi> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: yrl.pp-manager.tt@hitachi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: David S. Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20130314115242.19690.33573.stgit@mhiramat-M0-7522 Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Mon, 18 Mar 2013 09:00:56 +0000 (10:00 +0100)]
Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
. perf probe: Fix segfault due to testing the wrong pointer for NULL,
from Ananth N Mavinakayanahalli.
. libtraceevent: Remove hard coded include to /usr/local/include in
Makefile, which causes cross builds to include host header files,
fix from Jack Mitchell.
. perf record: Use the right target interface for synthesizing
threads when --cpu/-C option is used, fix from Jiri Olsa.
. Check if -DFORTIFY_SOURCE=2 is allowed, as gcc 4.7.2 defines
it and then the build is broken when it is redefined in perf,
fix from Marcin Slusarz.
. Fix build with NO_NEWT=1, that can happen explicitely or when
the newt-devel package is not installed, from Michael Ellerman.
. perf/POWER7: Create a sysfs format entry for Power7 events, missing
patch from a patchseries already merged, from Sukadev Bhattiprolu.
. Fix LIBNUMA build with glibc 2.12 and older, from Vinson Lee.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
Namhyung Kim [Fri, 15 Mar 2013 07:27:13 +0000 (16:27 +0900)]
perf: Generate EXIT event only once per task context
perf_event_task_event() iterates pmu list and generate events
for each eligible pmu context. But if task_event has task_ctx
like in EXIT it'll generate events even though the pmu doesn't
have an eligible one. Fix it by moving the code to proper
places.
Before this patch:
$ perf record -n true
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.006 MB perf.data (~248 samples) ]
$ perf report -D | tail
Aggregated stats:
TOTAL events: 73
MMAP events: 67
COMM events: 2
EXIT events: 4
cycles stats:
TOTAL events: 73
MMAP events: 67
COMM events: 2
EXIT events: 4
After this patch:
$ perf report -D | tail
Aggregated stats:
TOTAL events: 70
MMAP events: 67
COMM events: 2
EXIT events: 1
cycles stats:
TOTAL events: 70
MMAP events: 67
COMM events: 2
EXIT events: 1
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1363332433-7637-1-git-send-email-namhyung@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Namhyung Kim [Mon, 18 Mar 2013 02:41:46 +0000 (11:41 +0900)]
perf: Reset hwc->last_period on sw clock events
When cpu/task clock events are initialized, their sampling
frequencies are converted to have a fixed value. However it
missed to update the hwc->last_period which was set to 1 for
initial sampling frequency calibration.
Because this hwc->last_period value is used as a period in
perf_swevent_ hrtime(), every recorded sample will have an
incorrected period of 1.
$ perf record -e task-clock noploop 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.158 MB perf.data (~6919 samples) ]
The following patch causes 'perf stat --repeat 0' to be interpreted as
'forever', displaying the stats for every run.
We act as if a single run was asked, and reset the stats in each
iteration. In this mode SIGINT is passed to perf to be able to stop the
loop with Ctrl+C.
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20130301180227.GA24385@ks398093.ip-192-95-24.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Sun, 10 Mar 2013 18:41:10 +0000 (19:41 +0100)]
perf tests: Test breakpoint overflow signal handler
Adding automated test for breakpoint event signal handler checking if
it's executed properly.
The test is related to the proper handling of the RF EFLAGS bit on
x86_64, but it's generic for all archs.
First we check the signal handler is properly called and that the
following debug exception return to user space wouldn't trigger
recursive breakpoint.
This is related to x86_64 RF EFLAGS bit being managed in a wrong way.
Second we check that we can set breakpoint in signal handler, which is
not possible on x86_64 if the signal handler is executed with RF EFLAG
set.
This test is inpired by overflow tests done by Vince Weaver.
Signed-off-by: Jiri Olsa <jolsa@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1362940871-24486-6-git-send-email-jolsa@redhat.com
[ committer note: s/pr_err/pr_debug/g i.e. print just OK or FAILED in non verbose mode ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>