linux-toradex.git/kernel/trace/trace_syscalls.c, branch tegra-9.12.14

tracing/syscalls: Use long for syscall ret format and field definitions

2009-10-06T10:02:34+00:00

The syscall event definitions use long for the syscall exit ret
value, but unsigned long for the same thing in the format and field
definitions.  Change them all to long.

Signed-off-by: Tom Zanussi 
Acked-by: Frederic Weisbecker 
Cc: rostedt@goodmis.org
Cc: lizf@cn.fujitsu.com
Cc: Peter Zijlstra 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Arnaldo Carvalho de Melo 
LKML-Reference: <1254808849-7829-4-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar

Merge branch 'perfcounters-rename-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-09-21T16:15:07+00:00

* 'perfcounters-rename-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf: Tidy up after the big rename
  perf: Do the big rename: Performance Counters -> Performance Events
  perf_counter: Rename 'event' to event_id/hw_event
  perf_counter: Rename list_entry -> group_entry, counter_list -> group_list

Manually resolved some fairly trivial conflicts with the tracing tree in
include/trace/ftrace.h and kernel/trace/trace_syscalls.c.

perf: Do the big rename: Performance Counters -> Performance Events

2009-09-21T12:28:04+00:00

Bye-bye Performance Counters, welcome Performance Events!

In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.

Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.

All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)

The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.

Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.

User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)

This patch has been generated via the following script:

  FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

  sed -i \
    -e 's/PERF_EVENT_/PERF_RECORD_/g' \
    -e 's/PERF_COUNTER/PERF_EVENT/g' \
    -e 's/perf_counter/perf_event/g' \
    -e 's/nb_counters/nb_events/g' \
    -e 's/swcounter/swevent/g' \
    -e 's/tpcounter_event/tp_event/g' \
    $FILES

  for N in $(find . -name perf_counter.[ch]); do
    M=$(echo $N | sed 's/perf_counter/perf_event/g')
    mv $N $M
  done

  FILES=$(find . -name perf_event.*)

  sed -i \
    -e 's/COUNTER_MASK/REG_MASK/g' \
    -e 's/COUNTER/EVENT/g' \
    -e 's/\/event_id/g' \
    -e 's/counter/event/g' \
    -e 's/Counter/Event/g' \
    $FILES

... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.

Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.

( NOTE: 'counters' are still the proper terminology when we deal
  with hardware registers - and these sed scripts are a bit
  over-eager in renaming them. I've undone some of that, but
  in case there's something left where 'counter' would be
  better than 'event' we can undo that on an individual basis
  instead of touching an otherwise nicely automated patch. )

Suggested-by: Stephane Eranian 
Acked-by: Peter Zijlstra 
Acked-by: Paul Mackerras 
Reviewed-by: Arjan van de Ven 
Cc: Mike Galbraith 
Cc: Arnaldo Carvalho de Melo 
Cc: Frederic Weisbecker 
Cc: Steven Rostedt 
Cc: Benjamin Herrenschmidt 
Cc: David Howells 
Cc: Kyle McMartin 
Cc: Martin Schwidefsky 
Cc: "David S. Miller" 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Cc: 
LKML-Reference: 
Signed-off-by: Ingo Molnar

tracing: Allocate the ftrace event profile buffer dynamically

2009-09-18T05:25:44+00:00

Currently the trace event profile buffer is allocated in the stack. But
this may be too much for the stack, as the events can have large
statically defined field size and can also grow with dynamic arrays.

Allocate two per cpu buffer for all profiled events. The first cpu
buffer is used to host every non-nmi context traces. It is protected
by disabling the interrupts while writing and committing the trace.

The second buffer is reserved for nmi. So that there is no race between
them and the first buffer.

The whole write/commit section is rcu protected because we release
these buffers while deactivating the last profiling trace event.

v2: Move the buffers from trace_event to be global, as pointed by
    Steven Rostedt.

v3: Fix the syscall events to handle the profiling buffer races
    by disabling interrupts, now that the buffers are globals.

Suggested-by: Steven Rostedt 
Signed-off-by: Frederic Weisbecker 
Cc: Steven Rostedt 
Cc: Peter Zijlstra 
Cc: Li Zefan 
Cc: Jason Baron 
Cc: Masami Hiramatsu 
Cc: Ingo Molnar

tracing: pass around ring buffer instead of tracer

2009-09-04T22:59:39+00:00

The latency tracers (irqsoff and wakeup) can swap trace buffers
on the fly. If an event is happening and has reserved data on one of
the buffers, and the latency tracer swaps the global buffer with the
max buffer, the result is that the event may commit the data to the
wrong buffer.

This patch changes the API to the trace recording to be recieve the
buffer that was used to reserve a commit. Then this buffer can be passed
in to the commit.

Signed-off-by: Steven Rostedt

tracing: Convert event tracing code to use NR_syscalls

2009-08-26T19:30:02+00:00

Convert the syscalls event tracing code to use NR_syscalls, instead of
FTRACE_SYSCALL_MAX. NR_syscalls is standard accross most arches, and
reduces code confusion/complexity.

Signed-off-by: Jason Baron 
Cc: Paul Mundt 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Lai Jiangshan 
Cc: Steven Rostedt 
Cc: Peter Zijlstra 
Cc: Mathieu Desnoyers 
Cc: Jiaying Zhang 
Cc: Martin Bligh 
Cc: Li Zefan 
Cc: Josh Stone 
Cc: Thomas Gleixner 
Cc: H. Peter Anwin 
Cc: Hendrik Brueckner 
Cc: Heiko Carstens 
LKML-Reference: <9b4f1a84ecae57cc6599412772efa36f0d2b815b.1251146513.git.jbaron@redhat.com>
Signed-off-by: Frederic Weisbecker

tracing: Check invalid syscall nr while tracing syscalls

2009-08-26T19:29:48+00:00

Most arch syscall_get_nr() implementations returns -1 if the syscall
number is not valid.  Accessing the bit field without a check might
result in a kernel oops (at least I saw it on s390 for ftrace selftest).

Before this change, this problem did not occur, because the invalid
syscall number (-1) caused syscall_nr_to_meta() to return NULL.

There are at least two scenarios where syscall_get_nr() can return -1:

1. For example, ptrace stores an invalid syscall number, and thus,
   tracing code resets it.
   (see do_syscall_trace_enter in arch/s390/kernel/ptrace.c)

2. The syscall_regfunc() (kernel/tracepoint.c) sets the
   TIF_SYSCALL_FTRACE (now: TIF_SYSCALL_TRACEPOINT) flag for all threads
   which include kernel threads.
   However, the ftrace selftest triggers a kernel oops when testing
   syscall trace points:
      - The kernel thread is started as ususal (do_fork()),
      - tracing code sets TIF_SYSCALL_FTRACE,
      - the ret_from_fork() function is triggered and starts
	ftrace_syscall_exit() with an invalid syscall number.

To avoid these scenarios, I suggest to check the syscall_nr.

For instance, the ftrace selftest fails for s390 (with config option
CONFIG_FTRACE_SYSCALLS set) and produces the following kernel oops.

Unable to handle kernel pointer dereference at virtual kernel address 2000000000

Oops: 0038 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 Not tainted 2.6.31-rc6-next-20090819-dirty #18
Process kthreadd (pid: 818, task: 000000003ea207e8, ksp: 000000003e813eb8)
Krnl PSW : 0704100180000000 00000000000ea54c (ftrace_syscall_exit+0x58/0xdc)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0 EA:3
Krnl GPRS: 0000000000000000 00000000000e0000 ffffffffffffffff 20000000008c2650
           0000000000000007 0000000000000000 0000000000000000 0000000000000000
           0000000000000000 0000000000000000 ffffffffffffffff 000000003e813d78
           000000003e813f58 0000000000505ba8 000000003e813e18 000000003e813d78
Krnl Code: 00000000000ea540: e330d0000008       ag      %r3,0(%r13)
           00000000000ea546: a7480007           lhi     %r4,7
           00000000000ea54a: 1442               nr      %r4,%r2
          >00000000000ea54c: e31030000090       llgc    %r1,0(%r3)
           00000000000ea552: 5410d008           n       %r1,8(%r13)
           00000000000ea556: 8a104000           sra     %r1,0(%r4)
           00000000000ea55a: 5410d00c           n       %r1,12(%r13)
           00000000000ea55e: 1211               ltr     %r1,%r1
Call Trace:
([<0000000000000000>] 0x0)
 [<000000000001fa22>] do_syscall_trace_exit+0x132/0x18c
 [<000000000002d0c4>] sysc_return+0x0/0x8
 [<000000000001c738>] kernel_thread_starter+0x0/0xc
Last Breaking-Event-Address:
 [<00000000000ea51e>] ftrace_syscall_exit+0x2a/0xdc

Signed-off-by: Hendrik Brueckner 
Acked-by: Heiko Carstens 
Cc: Jason Baron 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Lai Jiangshan 
Cc: Steven Rostedt 
Cc: Peter Zijlstra 
Cc: Mathieu Desnoyers 
Cc: Jiaying Zhang 
Cc: Martin Bligh 
Cc: Li Zefan 
Cc: Martin Schwidefsky 
Cc: Paul Mundt 
LKML-Reference: <20090825125027.GE4639@cetus.boeblingen.de.ibm.com>
Signed-off-by: Frederic Weisbecker

Merge branch 'tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core

2009-08-26T06:29:02+00:00

Conflicts:
	include/linux/tracepoint.h

Signed-off-by: Ingo Molnar

tracing/filters: Add __field_ext() to TRACE_EVENT

2009-08-26T04:32:06+00:00

Add __field_ext(), so a field can be assigned to a specific
filter_type, which matches a corresponding filter function.

For example, a later patch will allow this:
	__field_ext(const char *, str, FILTER_PTR_STR);

Signed-off-by: Li Zefan 
LKML-Reference: <4A7B9272.6050709@cn.fujitsu.com>

[
  Fixed a -1 to FILTER_OTHER
  Forward ported to latest kernel.
]

Signed-off-by: Steven Rostedt

tracing: Create generic syscall TRACE_EVENTs

2009-08-25T22:41:48+00:00

This converts the syscall_enter/exit tracepoints into TRACE_EVENTs, so
you can have generic ftrace events that capture all system calls with
arguments and return values.  These generic events are also renamed to
sys_enter/exit, so they're more closely aligned to the specific
sys_enter_foo events.

Signed-off-by: Josh Stone 
Cc: Jason Baron 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Li Zefan 
Cc: Steven Rostedt 
Cc: Peter Zijlstra 
Cc: Mathieu Desnoyers 
Cc: Jiaying Zhang 
Cc: Martin Bligh 
Cc: Lai Jiangshan 
Cc: Paul Mundt 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
LKML-Reference: <1251150194-1713-5-git-send-email-jistone@redhat.com>
Signed-off-by: Frederic Weisbecker