Support string type tracing and printing in kprobe-tracer.

This allows user to trace string data in kernel including __user data. Note
that sometimes __user data may not be accessed if it is paged-out (sorry, but
kprobes operation should be done in atomic, we can not wait for page-in).

Commiter note: Fixed up conflicts with b7e2ecef.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100519195724.2885.18788.stgit@localhost6.localdomain6>
Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

make version 3.80 doesn't support "else ifdef" on the same line, also it
doesn't support unindented nested constructs.

Build fails with:
Makefile:608: Extraneous text after `else' directive
Makefile:611: *** only one `else' per conditional.  Stop.

This patch fixes the build for make 3.80.

Cc: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <1277990366-1462-1-git-send-email-conny.seidel@amd.com>
Signed-off-by: NConny Seidel <conny.seidel@.amd.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When compiling perf on latest tip/master I see the following
error:

  cc1: warnings being treated as errors
  util/newt.c: In function 'hist_entry__tui_annotate':
  util/newt.c:764: warning: 'ret' is used uninitialized in
  this function make: *** [util/newt.o] Error 1

I think the problem was introduced by commit
13f499f0

Below is a patch that fixes the problem.
Signed-off-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20100629173226.GC23231@linux.vnet.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix resume_execution() and is_IF_modifier() to skip x86
instruction prefixes correctly by using x86 instruction
attribute.

Without this fix, resume_execution() can't handle instructions
which have non-REX prefixes (REX prefixes are skipped). This
will cause unexpected kernel panic by hitting bad address when a
kprobe hits on two-byte ret (e.g. "repz ret" generated for
Athlon/K8 optimization), because it just checks "repz" and can't
recognize the "ret" instruction.

These prefixes can be found easily with x86 instruction
attribute. This patch introduces skip_prefixes() and uses it in
resume_execution() and is_IF_modifier() to skip prefixes.
Signed-off-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <4C298A6E.8070609@hitachi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Because kprobes and syscalls need special processing to register
events, the class->reg() method was created to handle the differences.

But instead of creating a default ->reg for perf and ftrace events,
the code was scattered with:

	if (class->reg)
		class->reg();
	else
		default_reg();

This is messy and can also lead to bugs.

This patch cleans up this code and creates a default reg() entry for
the events allowing for the code to directly call the class->reg()
without the condition.
Reported-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

The nsecs_str string is a local variable defined as:

char nsecs_str[5];

It is possible for the snprintf call to use a size value larger than the
size of the string. This should not cause a buffer overrun as it is
written now due to the value for the string format "%03lu" can not be
larger than 1000. However, this change makes it correct. By making the
size correct we guard against potential future changes that could actually
cause a buffer overrun.
Signed-off-by: NChase Douglas <chase.douglas@canonical.com>
LKML-Reference: <1276619355-18116-1-git-send-email-chase.douglas@canonical.com>

[ added 'UL' to number 8 to fix gcc warning comparing it to sizeof() ]
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Let trace_module_add_events() and event_trace_init() call
__trace_add_event_call().
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA37E9.1020106@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

raw_init callback is optional.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA37D4.7070500@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Every event (or event class) has it's define_fields callback,
so the test is redundant.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA37BC.8080707@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Convert sched_wait_task to DEFINE_EVENT, and save ~1K:

   text    data     bss     dec     hex filename
 104595    9424    4992  119011   1d0e3 kernel/sched.o.orig
 103619    9344    4992  117955   1ccc3 kernel/sched.o

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA3787.2040800@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Use DECLARE_EVENT_CLASS, and save ~2.3K:

   text    data     bss     dec     hex filename
7018823 2031888 7251132 16301843         f8bf13 vmlinux.o.orig
7016727 2031696 7251132 16299555         f8b623 vmlinux.o

5 events are converted:

  timer_class:   timer_init, timer_expire_exit, timer_cancel
  hrtimer_class: hrtimer_init, hrtimer_cancel

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA3773.3060200@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Every event has the same common fields, so it's a big waste of
memory to have a copy of those fields for every event.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA3759.30105@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

All syscall exit events have the same fields.

The kernel size drops 2.5K:

   text    data     bss     dec     hex filename
7018612 2034376 7251132 16304120         f8c7f8 vmlinux.o.orig
7018612 2031888 7251132 16301632         f8be40 vmlinux.o
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA3746.8070100@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Reason: Further changes conflict with upstream fixes
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

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

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Fix undeclared ENOSYS in include/linux/tracepoint.h
  perf record: prevent kill(0, SIGTERM);
  perf session: Remove threads from tree on PERF_RECORD_EXIT
  perf/tracing: Fix regression of perf losing kprobe events
  perf_events: Fix Intel Westmere event constraints
  perf record: Don't call newt functions when not initialized

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

* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Deal with desc->set_type() changing desc->chip

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

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Prevent compiler from optimising the sched_avg_update() loop
  sched: Fix over-scheduling bug
  sched: Fix PROVE_RCU vs cpu_cgroup

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

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  nohz: Fix nohz ratelimit

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

* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: silence PROVE_RCU in sched_fork()
  idr: fix RCU lockdep splat in idr_get_next()
  rcu: apply RCU protection to wake_affine()

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, Calgary: Increase max PHB number
  x86: Fix rebooting on Dell Precision WorkStation T7400
  x86: Fix vsyscall on gcc 4.5 with -Os
  x86, pat: Proper init of memtype subtree_max_end
  um, hweight: Fix UML boot crash due to x86 optimized hweight
  x86, setup: Set ax register in boot vga query
  percpu, x86: Avoid warnings of unused variables in per cpu
  x86, irq: Rename gsi_end gsi_top, and fix off by one errors
  x86: use __ASSEMBLY__ rather than __ASSEMBLER__

* 'fixes' of ssh://master.kernel.org/~sfr/next-fixes:
  acpi: update gfp/slab.h includes
  ocfs2: update gfp/slab.h includes
  davinci: update gfp/slab.h includes
  arm: update gfp/slab.h includes
  v4l-dvb: update gfp/slab.h includes

* 'for-linus' of git://neil.brown.name/md:
  md/raid5: don't include 'spare' drives when reshaping to fewer devices.
  md/raid5: add a missing 'continue' in a loop.
  md/raid5: Allow recovered part of partially recovered devices to be in-sync
  md/raid5: More careful check for "has array failed".
  md: Don't update ->recovery_offset when reshaping an array to fewer devices.
  md/raid5: avoid oops when number of devices is reduced then increased.
  md: enable raid4->raid0 takeover
  md: clear layout after ->raid0 takeover
  md: fix raid10 takeover: use new_layout for setup_conf
  md: fix handling of array level takeover that re-arranges devices.
  md: raid10: Fix null pointer dereference in fix_read_error()
  Restore partition detection of newly created md arrays.

Implicit slab.h inclusion via percpu.h is about to go away.  Make sure
gfp.h or slab.h is included as necessary.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Implicit slab.h inclusion via percpu.h is about to go away.  Make sure
gfp.h or slab.h is included as necessary.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Joel Becker <joel.becker@oracle.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Implicit slab.h inclusion via percpu.h is about to go away.  Make sure
gfp.h or slab.h is included as necessary.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Implicit slab.h inclusion via percpu.h is about to go away.  Make sure
gfp.h or slab.h is included as necessary.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Implicit slab.h inclusion via percpu.h is about to go away.  Make sure
gfp.h or slab.h is included as necessary.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: fix first chunk match in per_cpu_ptr_to_phys()
  percpu: fix trivial bugs in pcpu_build_alloc_info()

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (52 commits)
  phylib: Add autoload support for the LXT973 phy.
  ISDN: hysdn, fix potential NULL dereference
  vxge: fix memory leak in vxge_alloc_msix() error path
  isdn/gigaset: correct CAPI connection state storage
  isdn/gigaset: encode HLC and BC together
  isdn/gigaset: correct CAPI DATA_B3 Delivery Confirmation
  isdn/gigaset: correct CAPI voice connection encoding
  isdn/gigaset: honor CAPI application's buffer size request
  cpmac: do not leak struct net_device on phy_connect errors
  smc91c92_cs: fix the problem that lan & modem does not work simultaneously
  ipv6: fix NULL reference in proxy neighbor discovery
  Bluetooth: Bring back var 'i' increment
  xfrm: check bundle policy existance before dereferencing it
  sky2: enable rx/tx in sky2_phy_reinit()
  cnic: Disable statistics initialization for eth clients that do not support statistics
  net: add dependency on fw class module to qlcnic and netxen_nic
  snmp: fix SNMP_ADD_STATS()
  hso: remove setting of low_latency flag
  udp: Fix bogus UFO packet generation
  lasi82596: fix netdev_mc_count conversion
  ...

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFSv4: Fix an embarassing typo in encode_attrs()
  NFSv4: Ensure that /proc/self/mountinfo displays the minor version number
  NFSv4.1: Ensure that we initialise the session when following a referral
  SUNRPC: Fix a re-entrancy bug in xs_tcp_read_calldir()
  nfs4 use mandatory attribute file type in nfs4_get_root

* 'sh/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
  clocksource: sh_cmt: Fix up bogus shift value.
  arch/sh/mm: Eliminate a double lock
  sh: Fix up IORESOURCE_PCI_FIXED usage in pcibios_fixup_device_resources().
  sh: remove duplicated #include

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  MAINTAINERS - Add an entry for the input MT protocol
  Input: wacom - fix serial number handling on Cintiq 21UX2
  Input: fixup X86_MRST selects
  Input: sysrq - fix "stuck" SysRq mode
  Input: ad7877 - fix spi word size to 16 bit
  Input: pcf8574_keypad - fix off by one in pcf8574_kp_irq_handler()

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  ext3: update ctime when changing the file's permission by setfacl
  ext2: update ctime when changing the file's permission by setfacl

* 'virtio' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6:
  virtio-pci: disable msi at startup
  virtio: return ENOMEM on out of memory

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI/PM: Do not use native PCIe PME by default

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  ALSA: usb/endpoint, fix dangling pointer use
  ALSA: asihpi - Get rid of incorrect "long" types and casts.
  ASoC: DaVinci: Fix McASP hardware FIFO configuration
  ALSA: hda - Fix line-in for mb5 model MacBook (Pro) 5,1 / 5,2
  ALSA: usb-audio: fix UAC2 control value queries
  ALSA: usb-audio: parse UAC2 sample rate ranges correctly
  ALSA: usb-audio: fix control messages for USB_RECIP_INTERFACE
  ALSA: usb-audio: add check for faulty clock in parse_audio_format_rates_v2()
  ALSA: hda - Don't check capture source mixer if no ADC is available

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  hwmon: (k8temp) Bypass core swapping on single-core processors
  hwmon: (i5k_amb) Fix sysfs attribute for lockdep
  hwmon: (k10temp) Do not blacklist known working CPU models

* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
  watchdog: at32ap700x_wdt: register misc device last in probe() function
  watchdog: [PATCH 3/3] imx2_wdt: fix section mismatch

* git://git.infradead.org/iommu-2.6:
  intel-iommu: Force-disable IOMMU for iGFX on broken Cantiga revisions.
  intel-iommu: Fix double lock in get_domain_for_dev()
  intel-iommu: Fix reference by physical address in intel_iommu_attach_device()

* 'for-linus' of git://gitorious.org/linux-omap-dss2/linux:
  OMAP: OMAPFB: fix rfbi.c compile error
  OMAPFB: LCDC: change update_mode to DISABLED when going suspend