Both ftrace_location() and ftrace_text_reserved() do basically the same thing.
They search to see if an address is in the ftace table (contains an address
that may change from nop to call ftrace_caller). The difference is
that ftrace_location() searches a single address, but ftrace_text_reserved()
searches a range.

This also makes the ftrace_text_reserved() faster as it now uses a bsearch()
instead of linearly searching all the addresses within a page.

Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

As all records in a page of the ftrace table are sorted, we can
speed up the search algorithm by checking if the address to look for
falls in between the first and last record ip on the page.

This speeds up both the ftrace_location() and ftrace_text_reserved()
algorithms, as it can skip full pages when the search address is
not in them.

Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

The ftrace_record_ip() and ftrace_alloc_dyn_node() were from the
time of the ftrace daemon. Although they were still used, they
still make things a bit more complex than necessary.

Move the code into the one function that uses it, and remove the
helper functions.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Instead of just sorting the ip's of the functions per ftrace page,
sort the entire list before adding them to the ftrace pages.

This will allow the bsearch algorithm to be sped up as it can
also sort by pages, not just records within a page.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

According to Documentation/trace/ftrace.txt:

tracing_cpumask:

        This is a mask that lets the user only trace
        on specified CPUS. The format is a hex string
        representing the CPUS.

The tracing_cpumask currently doesn't affect the tracing state of
per-CPU ring buffers.

This patch enables/disables CPU recording as its corresponding bit in
tracing_cpumask is set/unset.

Link: http://lkml.kernel.org/r/1336096792-25373-3-git-send-email-vnagarnaik@google.com

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

If tracing_dentry_percpu() failed, tracing_init_debugfs_percpu()
will try to create each cpu directories on debugfs' root directory
as d_percpu is NULL.

Link: http://lkml.kernel.org/r/1335143517-2285-1-git-send-email-namhyung.kim@lge.com

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

When the ring buffer does its consistency test on itself, it
removes the head page, runs the tests, and then adds it back
to what the "head_page" pointer was. But because the head_page
pointer may lack behind the real head page (held by the link
list pointer). The reset may be incorrect.

Instead, if the head_page exists (it does not on first allocation)
reset it back to the real head page before running the consistency
tests. Then it will be put back to its original location after
the tests are complete.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

There use to be ring buffer integrity checks after updating the
size of the ring buffer. But now that the ring buffer can modify
the size while the system is running, the integrity checks were
removed, as they require the ring buffer to be disabed to perform
the check.

Move the integrity check to the reading of the ring buffer via the
iterator reads (the "trace" file). As reading via an iterator requires
disabling the ring buffer, it is a perfect place to have it.

If the ring buffer happens to be disabled when updating the size,
we still perform the integrity check.

Cc: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

This patch adds the capability to add new pages to a ring buffer
atomically while write operations are going on. This makes it possible
to expand the ring buffer size without reinitializing the ring buffer.

The new pages are attached between the head page and its previous page.

Link: http://lkml.kernel.org/r/1336096792-25373-2-git-send-email-vnagarnaik@google.com

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

This patch adds the capability to remove pages from a ring buffer
without destroying any existing data in it.

This is done by removing the pages after the tail page. This makes sure
that first all the empty pages in the ring buffer are removed. If the
head page is one in the list of pages to be removed, then the page after
the removed ones is made the head page. This removes the oldest data
from the ring buffer and keeps the latest data around to be read.

To do this in a non-racey manner, tracing is stopped for a very short
time while the pages to be removed are identified and unlinked from the
ring buffer. The pages are freed after the tracing is restarted to
minimize the time needed to stop tracing.

The context in which the pages from the per-cpu ring buffer are removed
runs on the respective CPU. This minimizes the events not traced to only
NMI trace contexts.

Link: http://lkml.kernel.org/r/1336096792-25373-1-git-send-email-vnagarnaik@google.com

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

On gcc 4.5 the function tracing_mark_write() would give a warning
of page2 being uninitialized. This is due to a bug in gcc because
the logic prevents page2 from being used uninitialized, and
gcc 4.6+ does not complain (correctly).

Instead of adding a "unitialized" around page2, which could show
a bug later on, I combined page1 and page2 into an array map_pages[].
This binds the two and the two are modified according to nr_pages
(what gcc 4.5 seems to ignore). This no longer gives a warning with
gcc 4.5 nor with gcc 4.6.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Fixing i386 allnoconfig built errors:

 arch/x86/built-in.o: In function `amd_pmu_hw_config':
 perf_event_amd.c:(.text+0xc3e1): undefined reference to `get_ibs_caps'
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Arjan & Linus Annotation Edition

 - Fix indirect calls beautifier, reported by Linus.

 - Use the objdump comments to nuke specificities about how access to a well
   know variable is encoded, suggested by Linus.

 - Show the number of places that jump to a target, requested by Arjan.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-1txmtzf71eqie5xcukbfxors@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Just press 'J' and see how many places jump to jump targets.

The hottest jump target appears in red, targets with more than one
source have a different color than single source jump targets.
Suggested-by: Arjan van de Ven <arjan@infradead.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-7452y0dmc02a20ooins7rn79@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Instead of simply marking an offset as a jump target. So that we can
implement a new feature: showing "jumpy" targets, I.e. addresses that
lots of places jump to.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-vc7b0u5yxgrubig0q61ayhxf@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

So that we don't special case disasm_line__free, allowing each
instruction class to provide an specialized destructor, like is needed
for 'lock'.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-xxw4vs5n077tf35jsvjzylhb@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It just chops off the 'lock' and uses the ins__find, etc machinery to
call instruction specific parsers/beautifiers.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-4913ba2dzakz5rivgumosqbh@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Starting with inc, incl, dec, decl.
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-jvh0jspefr5jyn0l7qko12st@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This:

     mov    0x95bbb6(%rip),%ecx        # ffffffff81ae8d04 <d_hash_shift>

Becomes:

     mov    d_hash_shift,%ecx

Ditto for many more instructions that take two operands.
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-i5opbyai2x6mn9e5yjmhx9k6@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

   callq  *0x10(%rax)

was being rendered in simplified mode as:

   callq  *10

I.e. hexa, but without the 0x and omitting the register. In such cases
just use the raw form.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-m91tv004h2m1fkfgu6ovx3hb@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Fixes and improvements for perf/core:

- perf_target: abstraction for --uid, --pid, --tid, --cpu, --all-cpus handling,
  eliminating code duplicated in the tools, having constraints that apply to
  all of them, from Namhyung Kim

- Fixes for handling fallback to cpu-clock on PPC, from David Ahern

- Fix for processing events with unknown size, from Jiri Olsa

- Compilation fix on 32-bit, from Jiri Olsa
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

That is what is used in vi and mutt, and as well on the 'annotate'
browser.

Eventually we can have keymappings to make people used to other key
associations more confortable.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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-fyln9286b8gx5q4n277l0djs@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core

Additional toggles have pushed the help line out of view on a modestly
sized terminal (120 columns wide). Shorten it to just reminders.
Signed-off-by: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1336510879-64610-1-git-send-email-dsahern@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf-record defaults to the H/W cycles event and if it is not supported
falls back to cpu-clock. Reset the event name as well.
Signed-off-by: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1336495811-58461-1-git-send-email-dsahern@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The 'perf top' command falls back to cpu-clock if the H/W cycles event
is not supported, but the event name is not updated leading to a
misleading header:

PerfTop: 8 irqs/sec  kernel:75.0%  exact:  0.0% [1000Hz cycles],  ...

Update the event name when the event type is changed so that the
header displays correctly:

PerfTop: 794 irqs/sec  kernel:100.0%  exact:  0.0% [1000Hz cpu-clock], ...
Signed-off-by: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1336495789-58420-1-git-send-email-dsahern@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf stat on PPC currently fails to run:

$ perf stat -- sleep 1
  Error: open_counter returned with 6 (No such device or address). /bin/dmesg may provide additional information.

  Fatal: Not all events could be opened.

The problem is that until 2.6.37 (behavior changed with commit b0a873eb)
perf on PPC returns ENXIO when hw_perf_event_init() fails. With this
patch we get the expected behavior:

$ perf stat -v -- sleep 1
cycles event is not supported by the kernel.
stalled-cycles-frontend event is not supported by the kernel.
stalled-cycles-backend event is not supported by the kernel.
instructions event is not supported by the kernel.
branches event is not supported by the kernel.
branch-misses event is not supported by the kernel.

...
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1336490956-57145-1-git-send-email-dsahern@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf-record on PPC is not falling back to cpu-clock:

$ perf record -ag -fo /tmp/perf.data -- sleep 1

  Error: sys_perf_event_open() syscall returned with 6 (No such device or address).  /bin/dmesg may provide additional information.

  Fatal: No CONFIG_PERF_EVENTS=y kernel support configured?

The problem is that until 2.6.37 (behavior changed with commit b0a873eb)
perf on PPC returns ENXIO when hw_perf_event_init() fails. With this
patch we get the expected behavior:

$ perf record -ag -fo /tmp/perf.data -v -- sleep 1
Old kernel, cannot exclude guest or host samples.
The cycles event is not supported, trying to fall back to cpu-clock-ticks
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.151 MB /tmp/perf.data (~6592 samples) ]
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1336490937-57106-1-git-send-email-dsahern@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Using PRIu64 for printing out u64 nr_events to fix compilation
for x86 32 bits.

Cc: Arun Sharma <asharma@fb.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank C. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1335958638-5160-7-git-send-email-jolsa@redhat.comSigned-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We can easily use a single callback for both sched-in and sched-out. This
reduces the code footprint in the scheduler path as well as removes
the PMU black spot otherwise present between the out and in callback.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-o56ajxp1edwqg6x9d31wb805@git.kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

The value of IbsOpCurCnt rolls over when it reaches IbsOpMaxCnt. Thus,
it is reset to zero by hardware. To get the correct count we need to
add the max count to it in case we received an ibs sample (valid bit
set).
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/1333390758-10893-13-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

After disabling IBS there could be still incomming NMIs with samples
that even have the valid bit cleared. Mark all this NMIs as handled to
avoid spurious interrupt messages.
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/1333390758-10893-12-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

When disabling ibs there might be the case where hardware continuously
generates interrupts. This is described in erratum #420 (Instruction-
Based Sampling Engine May Generate Interrupt that Cannot Be Cleared).
To avoid this we must clear the counter mask first and then clear the
enable bit. This patch implements this.

See Revision Guide for AMD Family 10h Processors, Publication #41322.

Note: We now keep track of the last read ibs config value which is
then used to disable ibs. To update the config value we pass now a
pointer to the functions reading it.
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/1333390758-10893-11-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

If the last hw period is too short we might hit the irq handler which
biases the results. Thus try to have a max last period that triggers
the sw overflow.
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/1333390758-10893-10-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

There are cases where the remaining period is smaller than the minimal
possible value. In this case the counter is restarted with the minimal
period. This is of no use as the interrupt handler will trigger
immediately again and most likely hits itself. This biases the
results.

So, if the remaining period is within the min range, we better do not
restart the counter and instead trigger the overflow.
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/1333390758-10893-9-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Simple patch that just renames some variables for better
understanding.
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/1333390758-10893-8-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

This patch adds support for precise event sampling with IBS. There are
two counting modes to count either cycles or micro-ops. If the
corresponding performance counter events (hw events) are setup with
the precise flag set, the request is redirected to the ibs pmu:

 perf record -a -e cpu-cycles:p ...    # use ibs op counting cycle count
 perf record -a -e r076:p ...          # same as -e cpu-cycles:p
 perf record -a -e r0C1:p ...          # use ibs op counting micro-ops

Each ibs sample contains a linear address that points to the
instruction that was causing the sample to trigger. With ibs we have
skid 0. Thus, ibs supports precise levels 1 and 2. Samples are marked
with the PERF_EFLAGS_EXACT flag set. In rare cases the rip is invalid
when IBS was not able to record the rip correctly. Then the
PERF_EFLAGS_EXACT flag is cleared and the rip is taken from pt_regs.

V2:
* don't drop samples in precise level 2 if rip is invalid, instead
  support the PERF_EFLAGS_EXACT flag
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/20120502103309.GP18810@erda.amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Each IBS sample contains a linear address of the instruction that
caused the sample to trigger. This address is more precise than the
rip that was taken from the interrupt handler's stack. Update the rip
with that address. We use this in the next patch to implement
precise-event sampling on AMD systems using IBS.
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/1333390758-10893-6-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Fixing profiling at a fixed frequency, in this case the freq value and
sample period was setup incorrectly. Since sampling periods are
adjusted we also allow periods that have lower 4 bits set.

Another fix is the setup of the hw counter: If we modify
hwc->sample_period, we also need to update hwc->last_period and
hwc->period_left.
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/1333390758-10893-5-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>