Functions print_graph_overhead() and print_graph_duration() displays
data for one field - DURATION.

I merged them into single function print_graph_duration(),
and added a way to display the empty parts of the field.

This way the print_graph_irq() function can use this column to display
the IRQ signs if needed and the DURATION field details stays inside
the print_graph_duration() function.
Signed-off-by: NJiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1307113131-10045-3-git-send-email-jolsa@redhat.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>

The display of absolute time and duration fields is based on the
latency field. This was added during the irqsoff/wakeup tracers
graph support changes.

It's causing confusion in what fields will be displayed for the
function_graph tracer itself. So I'm removing this depency, and
adding absolute time and duration fields to the preemptirqsoff
preemptoff irqsoff wakeup tracers.

With following commands:
	# echo function_graph > ./current_tracer
	# cat trace

This is what it looked like before:
# tracer: function_graph
#
#     TIME        CPU  DURATION                  FUNCTION CALLS
#      |          |     |   |                     |   |   |   |
 0)   0.068 us    |          } /* page_add_file_rmap */
 0)               |          _raw_spin_unlock() {
...

This is what it looks like now:
# tracer: function_graph
#
# CPU  DURATION                  FUNCTION CALLS
# |     |   |                     |   |   |   |
 0)   0.068 us    |                } /* add_preempt_count */
 0)   0.993 us    |              } /* vfsmount_lock_local_lock */
...

For preemptirqsoff preemptoff irqsoff wakeup tracers,
this is what it looked like before:
SNIP
#                       _-----=> irqs-off
#                      / _----=> need-resched
#                     | / _---=> hardirq/softirq
#                     || / _--=> preempt-depth
#                     ||| / _-=> lock-depth
#                     |||| /
# CPU  TASK/PID       |||||  DURATION                  FUNCTION CALLS
# |     |    |        |||||   |   |                     |   |   |   |
 1)    <idle>-0    |  d..1  0.000 us    |  acpi_idle_enter_simple();
...

This is what it looks like now:
SNIP
#
#                                       _-----=> irqs-off
#                                      / _----=> need-resched
#                                     | / _---=> hardirq/softirq
#                                     || / _--=> preempt-depth
#                                     ||| /
#     TIME        CPU  TASK/PID       ||||  DURATION                  FUNCTION CALLS
#      |          |     |    |        ||||   |   |                     |   |   |   |
   19.847735 |   1)    <idle>-0    |  d..1  0.000 us    |  acpi_idle_enter_simple();
...
Signed-off-by: NJiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1307113131-10045-2-git-send-email-jolsa@redhat.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>

Added <linux/atomic.h>,<linux/ktime.h> and Removed <asm/atomic.h>.
Added KERN_DEBUG to printk() functions.
Acked-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NPaul McQuade <tungstentide@gmail.com>
Link: http://lkml.kernel.org/r/4DE596B4.7030904@gmail.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>

Removed <asm/ftrace.h> because <linux/ftrace.h> was already declared.
Braces of struct's coding style fixed.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NPaul McQuade <tungstentide@gmail.com>
Link: http://lkml.kernel.org/r/4DE59711.3090900@gmail.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>

Add a trace option to disable tracing on free. When this option is
set, a write into the free_buffer file will not only shrink the
ring buffer down to zero, but it will also disable tracing.

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

The proc file entry buffer_size_kb is used to set the size of tracing
buffer. The memory to expand the buffer size is kernel memory. Consider
a use case where tracing is handled by a user space utility, which acts
as a gate keeper for tracing requests. In an OOM condition, tracing is
considered a low priority task and if the utility gets killed the ring
buffer memory cannot be released back to the kernel.

This patch adds a proc file called "free_buffer" whose purpose is to
stop tracing and free up the ring buffer when it is closed.

The user space process can then set the desired size in buffer_size_kb
file and open the fd to the "free_buffer" file. Under OOM condition, if
the process gets killed, the kernel closes the file descriptor. The
release handler stops the tracing and releases the kernel memory
automatically.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Michael Rubin <mrubin@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: NVaibhav Nagarnaik <vnagarnaik@google.com>
Link: http://lkml.kernel.org/r/1308012717-11148-1-git-send-email-vnagarnaik@google.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>

The tracing ring buffer is a group of per-cpu ring buffers where
allocation and logging is done on a per-cpu basis. The events that are
generated on a particular CPU are logged in the corresponding buffer.
This is to provide wait-free writes between CPUs and good NUMA node
locality while accessing the ring buffer.

However, the allocation routines consider NUMA locality only for buffer
page metadata and not for the actual buffer page. This causes the pages
to be allocated on the NUMA node local to the CPU where the allocation
routine is running at the time.

This patch fixes the problem by using a NUMA node specific allocation
routine so that the pages are allocated from a NUMA node local to the
logging CPU.

I tested with the getuid_microbench from autotest. It is a simple binary
that calls getuid() in a loop and measures the average time for the
syscall to complete. The following command was used to test:
$ getuid_microbench 1000000

Compared the numbers found on kernel with and without this patch and
found that logging latency decreases by 30-50 ns/call.
tracing with non-NUMA allocation - 569 ns/call
tracing with NUMA allocation     - 512 ns/call
Signed-off-by: NVaibhav Nagarnaik <vnagarnaik@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Rubin <mrubin@google.com>
Cc: David Sharp <dhsharp@google.com>
Link: http://lkml.kernel.org/r/1304470602-20366-1-git-send-email-vnagarnaik@google.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>

In using syscall tracing by concurrent processes, the wakeup() that is
called in the event commit function causes contention on the spin lock
of the waitqueue. I enabled sys_enter_getuid and sys_exit_getuid
tracepoints, and by running getuid_microbench from autotest in parallel
I found that the contention causes exponential latency increase in the
tracing path.

The autotest binary getuid_microbench calls getuid() in a tight loop for
the given number of iterations and measures the average time required to
complete a single invocation of syscall.

The patch schedules a delayed work after 2 ms once an event commit calls
to wake up the trace wait_queue. This removes the delay caused by
contention on spin lock in wakeup() and amortizes the wakeup() calls
scheduled over the 2 ms period.

In the following example, the script enables the sys_enter_getuid and
sys_exit_getuid tracepoints and runs the getuid_microbench in parallel
with the given number of processes. The output clearly shows the latency
increase caused by contentions.

$ ~/getuid.sh 1
1000000 calls in 0.720974253 s (720.974253 ns/call)

$ ~/getuid.sh 2
1000000 calls in 1.166457554 s (1166.457554 ns/call)
1000000 calls in 1.168933765 s (1168.933765 ns/call)

$ ~/getuid.sh 3
1000000 calls in 1.783827516 s (1783.827516 ns/call)
1000000 calls in 1.795553270 s (1795.553270 ns/call)
1000000 calls in 1.796493376 s (1796.493376 ns/call)

$ ~/getuid.sh 4
1000000 calls in 4.483041796 s (4483.041796 ns/call)
1000000 calls in 4.484165388 s (4484.165388 ns/call)
1000000 calls in 4.484850762 s (4484.850762 ns/call)
1000000 calls in 4.485643576 s (4485.643576 ns/call)

$ ~/getuid.sh 5
1000000 calls in 6.497521653 s (6497.521653 ns/call)
1000000 calls in 6.502000236 s (6502.000236 ns/call)
1000000 calls in 6.501709115 s (6501.709115 ns/call)
1000000 calls in 6.502124100 s (6502.124100 ns/call)
1000000 calls in 6.502936358 s (6502.936358 ns/call)

After the patch, the latencies scale better.
1000000 calls in 0.728720455 s (728.720455 ns/call)

1000000 calls in 0.842782857 s (842.782857 ns/call)
1000000 calls in 0.883803135 s (883.803135 ns/call)

1000000 calls in 0.902077764 s (902.077764 ns/call)
1000000 calls in 0.902838202 s (902.838202 ns/call)
1000000 calls in 0.908896885 s (908.896885 ns/call)

1000000 calls in 0.932523515 s (932.523515 ns/call)
1000000 calls in 0.958009672 s (958.009672 ns/call)
1000000 calls in 0.986188020 s (986.188020 ns/call)
1000000 calls in 0.989771102 s (989.771102 ns/call)

1000000 calls in 0.933518391 s (933.518391 ns/call)
1000000 calls in 0.958897947 s (958.897947 ns/call)
1000000 calls in 1.031038897 s (1031.038897 ns/call)
1000000 calls in 1.089516025 s (1089.516025 ns/call)
1000000 calls in 1.141998347 s (1141.998347 ns/call)
Signed-off-by: NVaibhav Nagarnaik <vnagarnaik@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Rubin <mrubin@google.com>
Cc: David Sharp <dhsharp@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1305059241-7629-1-git-send-email-vnagarnaik@google.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>

A lost Quilt refresh of 2c29ef0f (perf: Simplify and fix
__perf_install_in_context()) is causing grief and lockups,
reported by Jiri Olsa.

When installing an event in a task context, there's a number of
issues:

 - there might not be an existing task context, in which case
   we should install the now current context;

 - there might already be a context, not the current one, in
   which case we should de-schedule the old and install the new;

these cases were dealt with in the lost refresh, however there is one
further case that was found in testing:

 - there might already be a context, the current one, in which
   case we should still de-schedule, and should take care
   to re-install it (note that task_ctx_sched_out() clears
   cpuctx->task_ctx).
Reported-by: NJiri Olsa <jolsa@redhat.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1307399008.2497.971.camel@laptopSigned-off-by: NIngo Molnar <mingo@elte.hu>

Conflicts:
	tools/perf/util/python.c

Merge reason: resolve the conflict with perf/urgent.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Turns out that distro packages use this file as an indicator of
the perf event subsystem - this is easier to check for from scripts
than the existence of the system call.

This is easy enough to keep around for the kernel, so add a
comment to make sure it stays so.
Signed-off-by: NVince Weaver <vweaver1@eecs.utk.edu>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org
Cc: acme@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1106031751170.29381@cl320.eecs.utk.eduSigned-off-by: NIngo Molnar <mingo@elte.hu>

Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Mandatory arguments need to be present in the argument name list, as
well as optional arguments, otherwise python barfs:

	# ./python/twatch.py
	Traceback (most recent call last):
	  File "./python/twatch.py", line 41, in <module>
	    main()
	  File "./python/twatch.py", line 32, in main
	    event = evlist.read_on_cpu(cpu)
	RuntimeError: more argument specifiers than keyword list entries

Hence, add cpu to the name list.

Cc: David Ahern <daahern@cisco.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/r/1301588863-20210-1-git-send-email-fweisbec@gmail.comSigned-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Fixes two more cases where the python binding would not load:

. Not finding die(), which it shouldn't anyway, not good to just stop the
  world because some particular perf.data file is invalid, just propagate
  the error to the caller.

. Not finding perf_sample_size: fix it by moving it from event.c to evsel,
  where it belongs, as most cases are moving to operate on an evsel object.o

One of the fixed problems:

[root@emilia ~]# python
>>> import perf
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: /home/acme/git/build/perf/python/perf.so: undefined symbol: perf_sample_size
>>>
[root@emilia ~]#

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-1hkj7b2cvgbfnoizsekjb6c9@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We were using pr_debug to tell the user about not being able to parse a sample
where we should really use the python way of reporting errors: exceptions.

Fixes this problem:

[root@emilia ~]# python
>>> import perf
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: /home/acme/git/build/perf/python/perf.so: undefined symbol: eprintf
>>>
[root@emilia ~]

As we want to keep the objects linked in the python binding (and in the future
in a shared library) minimal.

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-m9dba9kaluas0kq8r58z191c@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

So far we avoided having to link debug.o in the python binding, keep it
that way by not using ui__warning() in evlist.c.

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-4wtew8hd3g7ejnlehtspys2t@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Merge reason: merge in the latest fixes.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Resolve to a function or variable if possible and if the sym option is
enabled.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1306782503-22002-1-git-send-email-dsahern@gmail.comSigned-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The 'sym' option displays both the function name and the DSO it comes
from. Split the display of the dso into a separate option.  This allows
display of the ip address and symbol without the dso, thus shortening
line lengths - and decluttering the output a bit.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1306528124-25861-3-git-send-email-dsahern@gmail.comSigned-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently the "sym" output field is used to dump instruction pointers
and callchain stack. Sample addresses can also be converted to symbols,
so the meaning of "sym" needs to be fixed. This patch adds an "ip"
option and if it is selected the user can also opt to dump symbols for
them. If the user opts to dump IP without syms only the address is
shown.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1306528124-25861-2-git-send-email-dsahern@gmail.comSigned-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

perf stat continues running even if the event list contains counters
that are not supported. The resulting output then contains <not counted>
for those events which gets confusing as to which events are supported,
but not counted and which are not supported.

Before:

perf stat -ddd -- sleep 1

      Performance counter stats for 'sleep 1':

          0.571283 task-clock                #    0.001 CPUs utilized
                 1 context-switches          #    0.002 M/sec
                 0 CPU-migrations            #    0.000 M/sec
               157 page-faults               #    0.275 M/sec
         1,037,707 cycles                    #    1.816 GHz
     <not counted> stalled-cycles-frontend
     <not counted> stalled-cycles-backend
           654,499 instructions              #    0.63  insns per cycle
           136,129 branches                  #  238.286 M/sec
     <not counted> branch-misses
     <not counted> L1-dcache-loads
     <not counted> L1-dcache-load-misses
     <not counted> LLC-loads
     <not counted> LLC-load-misses
     <not counted> L1-icache-loads
     <not counted> L1-icache-load-misses
     <not counted> dTLB-loads
     <not counted> dTLB-load-misses
     <not counted> iTLB-loads
     <not counted> iTLB-load-misses
     <not counted> L1-dcache-prefetches
     <not counted> L1-dcache-prefetch-misses

       1.001004836 seconds time elapsed

After:

perf stat -ddd -- sleep 1

 Performance counter stats for 'sleep 1':

          1.350326 task-clock                #    0.001 CPUs utilized
                 2 context-switches          #    0.001 M/sec
                 0 CPU-migrations            #    0.000 M/sec
               157 page-faults               #    0.116 M/sec
            11,986 cycles                    #    0.009 GHz
   <not supported> stalled-cycles-frontend
   <not supported> stalled-cycles-backend
           496,986 instructions              #   41.46  insns per cycle
           138,065 branches                  #  102.246 M/sec
             7,245 branch-misses             #    5.25% of all branches
     <not counted> L1-dcache-loads
     <not counted> L1-dcache-load-misses
     <not counted> LLC-loads
     <not counted> LLC-load-misses
     <not counted> L1-icache-loads
     <not counted> L1-icache-load-misses
     <not counted> dTLB-loads
     <not counted> dTLB-load-misses
     <not counted> iTLB-loads
     <not counted> iTLB-load-misses
     <not counted> L1-dcache-prefetches
   <not supported> L1-dcache-prefetch-misses

       1.002397333 seconds time elapsed

v1->v2:
changed supported type from int to bool

v2->v3
fixed vertical alignment of new struct element

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1306767359-13221-1-git-send-email-dsahern@gmail.comSigned-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The list of methods argument names only needs to be NULL terminated
once. Remove the second ones.

Cc: David Ahern <daahern@cisco.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/r/1301588863-20210-2-git-send-email-fweisbec@gmail.comSigned-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Mandatory arguments need to be present in the argument name list, as
well as optional arguments, otherwise python barfs:

	# ./python/twatch.py
	Traceback (most recent call last):
	  File "./python/twatch.py", line 41, in <module>
	    main()
	  File "./python/twatch.py", line 32, in main
	    event = evlist.read_on_cpu(cpu)
	RuntimeError: more argument specifiers than keyword list entries

Hence, add cpu to the name list.

Cc: David Ahern <daahern@cisco.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/r/1301588863-20210-1-git-send-email-fweisbec@gmail.comSigned-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Fixes two more cases where the python binding would not load:

. Not finding die(), which it shouldn't anyway, not good to just stop the
  world because some particular perf.data file is invalid, just propagate
  the error to the caller.

. Not finding perf_sample_size: fix it by moving it from event.c to evsel,
  where it belongs, as most cases are moving to operate on an evsel object.o

One of the fixed problems:

[root@emilia ~]# python
>>> import perf
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: /home/acme/git/build/perf/python/perf.so: undefined symbol: perf_sample_size
>>>
[root@emilia ~]#

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-1hkj7b2cvgbfnoizsekjb6c9@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We were using pr_debug to tell the user about not being able to parse a sample
where we should really use the python way of reporting errors: exceptions.

Fixes this problem:

[root@emilia ~]# python
>>> import perf
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: /home/acme/git/build/perf/python/perf.so: undefined symbol: eprintf
>>>
[root@emilia ~]

As we want to keep the objects linked in the python binding (and in the future
in a shared library) minimal.

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-m9dba9kaluas0kq8r58z191c@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

So far we avoided having to link debug.o in the python binding, keep it
that way by not using ui__warning() in evlist.c.

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-4wtew8hd3g7ejnlehtspys2t@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This reverts commit a197b59a.

As rmk says:
 "Commit a197b59a (mm: fail GFP_DMA allocations when ZONE_DMA is not
  configured) is causing regressions on ARM with various drivers which
  use GFP_DMA.

  The behaviour up until now has been to silently ignore that flag when
  CONFIG_ZONE_DMA is not enabled, and to allocate from the normal zone.
  However, as a result of the above commit, such allocations now fail
  which causes drivers to fail.  These are regressions compared to the
  previous kernel version."

so just revert it.
Requested-by: NRussell King <linux@arm.linux.org.uk>
Acked-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* git://git.infradead.org/iommu-2.6:
  intel-iommu: Fix off-by-one in RMRR setup
  intel-iommu: Add domain check in domain_remove_one_dev_info
  intel-iommu: Remove Host Bridge devices from identity mapping
  intel-iommu: Use coherent DMA mask when requested
  intel-iommu: Dont cache iova above 32bit
  intel-iommu: Speed up processing of the identity_mapping function
  intel-iommu: Check for identity mapping candidate using system dma mask
  intel-iommu: Only unlink device domains from iommu
  intel-iommu: Enable super page (2MiB, 1GiB, etc.) support
  intel-iommu: Flush unmaps at domain_exit
  intel-iommu: Remove obsolete comment from detect_intel_iommu
  intel-iommu: fix VT-d PMR disable for TXT on S3 resume

Jens' back-merge commit 698567f3 ("Merge commit 'v2.6.39' into
for-2.6.40/core") was incorrectly done, and re-introduced the
DISK_EVENT_MEDIA_CHANGE lines that had been removed earlier in commits

 - 9fd097b1 ("block: unexport DISK_EVENT_MEDIA_CHANGE for
   legacy/fringe drivers")

 - 7eec77a1 ("ide: unexport DISK_EVENT_MEDIA_CHANGE for ide-gd
   and ide-cd")

because of conflicts with the "g->flags" updates near-by by commit
d4dc210f ("block: don't block events on excl write for non-optical
devices")

As a result, we re-introduced the hanging behavior due to infinite disk
media change reports.

Tssk, tssk, people! Don't do back-merges at all, and *definitely* don't
do them to hide merge conflicts from me - especially as I'm likely
better at merging them than you are, since I do so many merges.
Reported-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* git://git.infradead.org/mtd-2.6:
  mtd: fix physmap.h warnings

We were mapping an extra byte (and hence usually an extra page):
iommu_prepare_identity_map() expects to be given an 'end' argument which
is the last byte to be mapped; not the first byte *not* to be mapped.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The comment in domain_remove_one_dev_info() states "No need to compare
PCI domain; it has to be the same". But for the si_domain that isn't
going to be true, as it consists of all the PCI devices that are
identity mapped thus multiple PCI domains can be in si_domain.  The
code needs to validate the PCI domain too.
Signed-off-by: NMike Habeck <habeck@sgi.com>
Signed-off-by: NMike Travis <travis@sgi.com>
Cc: stable@kernel.org
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

When using the 1:1 (identity) PCI DMA remapping, PCI Host Bridge devices
that do not use the IOMMU causes a kernel panic.  Fix that by not
inserting those devices into the si_domain.
Signed-off-by: NMike Travis <travis@sgi.com>
Reviewed-by: NMike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The __intel_map_single function is not honoring the passed in DMA mask.
This results in not using the coherent DMA mask when called from
intel_alloc_coherent().
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NChris Wright <chrisw@sous-sol.org>
Reviewed-by: NMike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Mike Travis and Mike Habeck reported an issue where iova allocation
would return a range that was larger than a device's dma mask.

https://lkml.org/lkml/2011/3/29/423

The dmar initialization code will reserve all PCI MMIO regions and copy
those reservations into a domain specific iova tree.  It is possible for
one of those regions to be above the dma mask of a device.  It is typical
to allocate iovas with a 32bit mask (despite device's dma mask possibly
being larger) and cache the result until it exhausts the lower 32bit
address space.  Freeing the iova range that is >= the last iova in the
lower 32bit range when there is still an iova above the 32bit range will
corrupt the cached iova by pointing it to a region that is above 32bit.
If that region is also larger than the device's dma mask, a subsequent
allocation will return an unusable iova and cause dma failure.

Simply don't cache an iova that is above the 32bit caching boundary.
Reported-by: NMike Travis <travis@sgi.com>
Reported-by: NMike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Acked-by: NMike Travis <travis@sgi.com>
Tested-by: NMike Habeck <habeck@sgi.com>
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

When there are a large count of PCI devices, and the pass through
option for iommu is set, much time is spent in the identity_mapping
function hunting though the iommu domains to check if a specific
device is "identity mapped".

Speed up the function by checking the cached info to see if
it's mapped to the static identity domain.
Signed-off-by: NMike Travis <travis@sgi.com>
Reviewed-by: NMike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The identity mapping code appears to make the assumption that if the
devices dma_mask is greater than 32bits the device can use identity
mapping.  But that is not true: take the case where we have a 40bit
device in a 44bit architecture. The device can potentially receive a
physical address that it will truncate and cause incorrect addresses
to be used.

Instead check to see if the device's dma_mask is large enough
to address the system's dma_mask.
Signed-off-by: NMike Travis <travis@sgi.com>
Reviewed-by: NMike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Commit a97590e5 added unlinking domains from iommus to reciprocate the
iommu from domains unlinking that was already done.  We actually want
to only do this for device domains and never for the static
identity map domain or VM domains.  The SI domain is special and
never freed, while VM domain->id lives in their own special address
space, separate from iommu->domain_ids.

In the current code, a VM can get domain->id zero, then mark that
domain unused when unbound from pci-stub.  This leads to DMAR
write faults when the device is re-bound to the host driver.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Cc: stable@kernel.org
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

There are no externally-visible changes with this. In the loop in the
internal __domain_mapping() function, we simply detect if we are mapping:
  - size >= 2MiB, and
  - virtual address aligned to 2MiB, and
  - physical address aligned to 2MiB, and
  - on hardware that supports superpages.

(and likewise for larger superpages).

We automatically use a superpage for such mappings. We never have to
worry about *breaking* superpages, since we trust that we will always
*unmap* the same range that was mapped. So all we need to do is ensure
that dma_pte_clear_range() will also cope with superpages.

Adjust pfn_to_dma_pte() to take a superpage 'level' as an argument, so
it can return a PTE at the appropriate level rather than always
extending the page tables all the way down to level 1. Again, this is
simplified by the fact that we should never encounter existing small
pages when we're creating a mapping; any old mapping that used the same
virtual range will have been entirely removed and its obsolete page
tables freed.

Provide an 'intel_iommu=sp_off' argument on the command line as a
chicken bit. Not that it should ever be required.

==

The original commit seen in the iommu-2.6.git was Youquan's
implementation (and completion) of my own half-baked code which I'd
typed into an email. Followed by half a dozen subsequent 'fixes'.

I've taken the unusual step of rewriting history and collapsing the
original commits in order to keep the main history simpler, and make
life easier for the people who are going to have to backport this to
older kernels. And also so I can give it a more coherent commit comment
which (hopefully) gives a better explanation of what's going on.

The original sequence of commits leading to identical code was:

Youquan Song (3):
      intel-iommu: super page support
      intel-iommu: Fix superpage alignment calculation error
      intel-iommu: Fix superpage level calculation error in dma_pfn_level_pte()

David Woodhouse (4):
      intel-iommu: Precalculate superpage support for dmar_domain
      intel-iommu: Fix hardware_largepage_caps()
      intel-iommu: Fix inappropriate use of superpages in __domain_mapping()
      intel-iommu: Fix phys_pfn in __domain_mapping for sglist pages
Signed-off-by: NYouquan Song <youquan.song@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>