We use:

  BUG_ON(!RB_EMPTY_NODE(&thread->rb_node));

in the thread destructor as a debugging check to find out about
possibly still referenced thread instances being deleted, to do that
we need to make sure we use RB_CLEAR_NODE() right after rb_erase(),
i.e. that we use the newly introduced rb_erase_init(), that works
just like list_del_init().

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-4fcqo5ypy1cjjf15ilb0hn78@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

I was assuming rb_erase() was setting things up like list_del_init, but
the fact that thread__delete() was being sucessfull is because the last
thing before deleting is to remove the thread from the
machine->dead_threads list, using list_del_init(), that has the same
effect as using rb_erase_init()...

Introduce this function so that we can use it when removing objects from
rb_trees.

Then we will be able to BUG_ON(still on a list) in destructors.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-55b16mbtndjyd7zzg8nmnamx@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Since:

	9fdbf671 "perf tools: do not flush maps on COMM for perf report"

We have no users of this function, nuke it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Luigi Semenzato <semenzato@chromium.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-hsac1t42ehtva8gut8qe6hih@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

A thread moves from a rb tree to a list, but can't be on both, because
those linkage members are in a union. This is leftover from when I was
debugging thread refcounting and had nuked that union.

It is harmless duplication, as RB_CLEAR_NODE() does again what
INIT_LIST_HEAD does.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-hmma9lmip6qlhzhgkhp9tzd1@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It really is a 'struct map' method, and since we're introducing a new
'struct maps' class, fix it to avoid confusion.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-xo9ifhk53cfl30wqcuhxpnvl@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Using dso__data_fd() in multi-thread environment is not safe since
returned fd can be closed and/or reused anytime.

So convert it to the dso__data_get/put_fd() pair to protect the access
with lock.

The original dso__data_fd() is deprecated and kept only for testing.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1432137821-10853-3-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It seems that the dso__data_fd() was needed to find a binary type
since open in data_file_size() alone used to fail.

But as it can open the dso fine now, the dso__data_fd() can go away.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1432137821-10853-2-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When dso__data_read_offset/addr() is called without prior dso__data_fd()
(or other functions which call it internally), it failed to open dso in
data_file_size() since its binary type was not identified.

However calling dso__data_fd() in dso__data_read_offset() will hurt
performance as it grabs a global lock everytime.  So factor out the loop
on the binary type in dso__data_fd(), and call it from both.
Reported-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1432137821-10853-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It could be used somewhere, so just call map__groups_put() to make sure
we don't delete it prematurely

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-dxmh8mr12i65p8h909vi88cp@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now that we have atomic.h, we should convert all of the existing
refcounts to use it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-quzeuy3jwsyod6e06o39cl6y@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To match the convention used elsewhere.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-66oo6yn8upssfeuprwy0il1q@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The evsel and sample arguments are to set iter for later use.  As it
also receives an iter as another argument, just set them before calling
the function.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1432022650-18205-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

perf_session__peek_event() generally leverages there being a single mmap
of the perf.data file, however on 32-bit platforms when there is more
that 32MiB of data, then there are multiple mmaps, so
perf_session__peek_event() reads from the file.

In that case a couple of bugs were exposed (note how the seg. fault
appears with >32M of data):

   $ perf record --per-thread -e intel_bts// ../rtit-tests/loopy 1000000
   [ perf record: Woken up 13 times to write data ]
   [ perf record: Captured and wrote 24.568 MB perf.data ]
   $ perf script > /dev/null
   $ perf record --per-thread -e intel_bts// ../rtit-tests/loopy 10000000
   [ perf record: Woken up 136 times to write data ]
   [ perf record: Captured and wrote 270.794 MB perf.data ]
   $ perf script > /dev/null
   Segmentation fault (core dumped)

The wrong address was being passed to the readn() function and the
buffer size was not being checked.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Link: http://lkml.kernel.org/r/1432040746-1755-5-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The libunwind feature would never detect because of the following error:

  $ cat tools/build/feature/test-libunwind.make.output
  /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_stream_buffer_decode'
  /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_uncompressed_size'
  /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_end'
  /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_buffer_decode'
  /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_stream_footer_decode'
  /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_size'
  collect2: error: ld returned 1 exit status

Fix by adding -llzma and re-ordering to match the dependencies.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Link: http://lkml.kernel.org/r/1432040746-1755-3-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Parse errors can be reported in struct parse_events_error but the
pointer passed is optional and can be NULL.  Ensure it is not NULL
before dereferencing it.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Link: http://lkml.kernel.org/r/1432040746-1755-4-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Patch "perf tools: Add location to pmu event terms" moved declarations
for parse_events_term__num() and parse_events_term__str() so that they
were no longer visible in parse-events.y. That can result in segfaults
as the arguments no longer need match the function prototype.

Move the declarations back, changing YYLTYPE pointers to
pointers-to-void because YYLTYPE is not generated until parse-events.y
is processed.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Link: http://lkml.kernel.org/r/1432040746-1755-2-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This refactors out install-bin to install-tests and install-tools so
that downstream could opt to only install the tools, and not the tests.
Signed-off-by: NNam T. Nguyen <namnguyen@chromium.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Simon Que <sque@chromium.org>
Link: http://lkml.kernel.org/r/1431974247-22275-1-git-send-email-namnguyen@chromium.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

There is a 'pt' variable in the outer scope of pt_event_stop() with the same
type, we don't really need another one in the inner scope.

This patch removes the redundant variable declaration.
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@infradead.org
Cc: adrian.hunter@intel.com
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1432308626-18845-8-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Initially, we were trying to guard against scenarios where somebody
attaches to the system with a hardware debugger while PT is enabled
from software and pt_is_running() tries to make sure we handle this
better, but the truth is, there is still a race window no matter what
and people with hardware debuggers should really know what they are
doing anyway.

In other words, there is no point in keeping this one around, and
it's one RDMSR instructions fewer in the fast path.

The case when PT is enabled by the BIOS at boot time is handled
in the driver initialization path and doesn't use pt_is_running().

This patch gets rid of it.
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@infradead.org
Cc: adrian.hunter@intel.com
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1429622177-22843-6-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Currently, the description of pt_buffer_reset_offsets() lacks information
about its calling constraints and ordering with regards to other buffer
management functions.

Add a clarification about when this function has to be called.
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@infradead.org
Cc: adrian.hunter@intel.com
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1429622177-22843-5-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The comments in the driver don't make it absolutely clear as to what
exactly is the calling order and other possible constraints of buffer
management functions.

Document constraints and calling order for the buffer configuration
functions. While at it, replace a redundant check in
pt_buffer_reset_markers() with an explanation why it is not needed.
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@infradead.org
Cc: adrian.hunter@intel.com
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1429622177-22843-4-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Currently, there's a set-but-not-used variable in setup_topa_index();
this patch gets rid of it. And while at it, fixes a style issue with
brackets around a one-line block.
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@infradead.org
Cc: adrian.hunter@intel.com
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1429622177-22843-2-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Don't bother with taking locks if we're not actually going to do
anything. Also, drop the _irqsave(), this is very much only called
from IRQ-disabled context.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

	!x && y == ! (x || !y)
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

For some obscure reason intel_{start,stop}_scheduling() copy the HT
state to an intermediate array. This would make sense if we ever were
to make changes to it which we'd have to discard.

Except we don't. By the time we call intel_commit_scheduling() we're;
as the name implies; committed to them. We'll never back out.

A further hint its pointless is that stop_scheduling() unconditionally
publishes the state.

So the intermediate array is pointless, modify the state in place and
kill the extra array.

And remove the pointless array initialization: INTEL_EXCL_UNUSED == 0.

Note; all is serialized by intel_excl_cntr::lock.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Both intel_commit_scheduling() and intel_get_excl_contraints() test
for cntr < 0.

The only way that can happen (aside from a bug) is through
validate_event(), however that is already captured by the
cpuc->is_fake test.

So remove these test and simplify the code.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Move the code of intel_commit_scheduling() to the right place, which is
in between start() and stop().

No change in functionality.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

The intel_commit_scheduling() callback is pointlessly different from
the start and stop scheduling callback.

Furthermore, the constraint should never be NULL, so remove that test.

Even though we'll never get called (because we NULL the callbacks)
when !is_ht_workaround_enabled() put that test in.

Collapse the (pointless) WARN_ON_ONCE() and bail on !cpuc->excl_cntrs --
this is doubly pointless, because its the same condition as
is_ht_workaround_enabled() which was already pointless because the
whole method won't ever be called.

Furthremore, make all the !excl_cntrs test WARN_ON_ONCE(); they're all
pointless, because the above, either the function
({get,put}_excl_constraint) are already predicated on it existing or
the is_ht_workaround_enabled() thing is the same test.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

We have two 'struct event_constraint' local variables in
intel_get_excl_constraints(): 'cx' and 'c'.

Instead of using 'cx' after the dynamic allocation, put all 'cx' inside
the dynamic allocation block and use 'c' outside of it.

Also use direct assignment to copy the structure; let the compiler
figure it out.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Lockdep is very good at finding incorrect IRQ state while locking and
is far better at telling us if we hold a lock than the _is_locked()
API. It also generates less code for !DEBUG kernels.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

For some obscure reason the current code accounts the current SMT
thread's state on the remote thread and reads the remote's state on
the local SMT thread.

While internally consistent, and 'correct' its pointless confusion we
can do without.

Flip them the right way around.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Since we write RMID values to MSRs the correct type to use is 'u32'
because that clearly articulates we're writing a hardware register
value.

Fix up all uses of RMID in this code to consistently use the correct data
type.
Reported-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Will Auld <will.auld@intel.com>
Link: http://lkml.kernel.org/r/1432285182-17180-1-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

'closid' (CLass Of Service ID) is used for the Class based Cache
Allocation Technology (CAT). Add explicit storage to the per cpu cache
for it, so it can be used later with the CAT support (requires to move
the per cpu data).

While at it:

 - Rename the structure to intel_pqr_state which reflects the actual
   purpose of the struct: cache values which go into the PQR MSR

 - Rename 'cnt' to rmid_usecnt which reflects the actual purpose of
   the counter.

 - Document the structure and the struct members.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NMatt Fleming <matt.fleming@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Will Auld <will.auld@intel.com>
Link: http://lkml.kernel.org/r/20150518235150.240899319@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

intel_cqm_event_del() is a 1:1 wrapper for intel_cqm_event_stop().
Remove the useless indirection.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NMatt Fleming <matt.fleming@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Will Auld <will.auld@intel.com>
Link: http://lkml.kernel.org/r/20150518235150.159779847@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

If the usage counter is non-zero there is no point to update the rmid
in the PQR MSR.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NMatt Fleming <matt.fleming@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Will Auld <will.auld@intel.com>
Link: http://lkml.kernel.org/r/20150518235150.080844281@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

'struct intel_cqm_state' is a strict per CPU cache of the rmid and the
usage counter. It can never be modified from a remote CPU.

The three functions which modify the content: intel_cqm_event[start|stop|del]
(del maps to stop) are called from the perf core with interrupts disabled
which is enough protection for the per CPU state values.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NMatt Fleming <matt.fleming@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Will Auld <will.auld@intel.com>
Link: http://lkml.kernel.org/r/20150518235150.001006529@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

'int' is really not a proper data type for an MSR. Use u32 to make it
clear that we are dealing with a 32-bit unsigned hardware value.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NMatt Fleming <matt.fleming@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Will Auld <will.auld@intel.com>
Link: http://lkml.kernel.org/r/20150518235149.919350144@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

The CQM code acts like it owns the PQR MSR completely. That's not true
because only the lower 10 bits are used for CQM. The upper 32 bits are
used for the 'CLass Of Service ID' (CLOSID). Document the abuse. Will be
fixed in a later patch.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NMatt Fleming <matt.fleming@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Will Auld <will.auld@intel.com>
Link: http://lkml.kernel.org/r/20150518235149.823214798@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

Signed-off-by: NIngo Molnar <mingo@kernel.org>

I stumbled upon an AMD box that had the BIOS using a hardware performance
counter. Instead of printing out a warning and continuing, it failed and
blocked further perf counter usage.

Looking through the history, I found this commit:

  a5ebe0ba ("perf/x86: Check all MSRs before passing hw check")

which tweaked the rules for a Xen guest on an almost identical box and now
changed the behaviour.

Unfortunately the rules were tweaked incorrectly and will always lead to
MSR failures even though the MSRs are completely fine.

What happens now is in arch/x86/kernel/cpu/perf_event.c::check_hw_exists():

<snip>
        for (i = 0; i < x86_pmu.num_counters; i++) {
                reg = x86_pmu_config_addr(i);
                ret = rdmsrl_safe(reg, &val);
                if (ret)
                        goto msr_fail;
                if (val & ARCH_PERFMON_EVENTSEL_ENABLE) {
                        bios_fail = 1;
                        val_fail = val;
                        reg_fail = reg;
                }
        }

<snip>
        /*
         * Read the current value, change it and read it back to see if it
         * matches, this is needed to detect certain hardware emulators
         * (qemu/kvm) that don't trap on the MSR access and always return 0s.
         */
        reg = x86_pmu_event_addr(0);
				^^^^

if the first perf counter is enabled, then this routine will always fail
because the counter is running. :-(

        if (rdmsrl_safe(reg, &val))
                goto msr_fail;
        val ^= 0xffffUL;
        ret = wrmsrl_safe(reg, val);
        ret |= rdmsrl_safe(reg, &val_new);
        if (ret || val != val_new)
                goto msr_fail;

The above bios_fail used to be a 'goto' which is why it worked in the past.

Further, most vendors have migrated to using fixed counters to hide their
evilness hence this problem rarely shows up now days except on a few old boxes.

I fixed my problem and kept the spirit of the original Xen fix, by recording a
safe non-enable register to be used safely for the reading/writing check.
Because it is not enabled, this passes on bare metal boxes (like metal), but
should continue to throw an msr_fail on Xen guests because the register isn't
emulated yet.

Now I get a proper bios_fail error message and Xen should still see their
msr_fail message (untested).
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: george.dunlap@eu.citrix.com
Cc: konrad.wilk@oracle.com
Link: http://lkml.kernel.org/r/1431976608-56970-1-git-send-email-dzickus@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>