Commit Graph

200 Commits

Author SHA1 Message Date
Robert Richter a0d76247e0 oprofile, s390: Rework hwsampler implementation
This patch is a rework of the hwsampler oprofile implementation that
has been applied recently. Now there are less non-architectural
changes. The only changes are:

* introduction of oprofile_add_ext_hw_sample(), and
* removal of section attributes of oprofile_timer_init/_exit().

To setup hwsampler for oprofile we need to modify start()/stop()
callbacks and additional hwsampler control files in oprofilefs. We do
not reinitialize the timer or hwsampler mode by restarting calling
init/exit() anymore, instead hwsampler_running is used to switch the
mode directly in oprofile_hwsampler_start/_stop(). For locking reasons
there is also hwsampler_file that reflects the value in oprofilefs.

The overall diffstat of the oprofile s390 hwsampler implemenation
shows the low impact to non-architectural code:

 arch/Kconfig                         |    3 +
 arch/s390/Kconfig                    |    1 +
 arch/s390/oprofile/Makefile          |    2 +-
 arch/s390/oprofile/hwsampler.c       | 1256 ++++++++++++++++++++++++++++++++++
 arch/s390/oprofile/hwsampler.h       |  113 +++
 arch/s390/oprofile/hwsampler_files.c |  162 +++++
 arch/s390/oprofile/init.c            |    6 +-
 drivers/oprofile/cpu_buffer.c        |   24 +-
 drivers/oprofile/timer_int.c         |    4 +-
 include/linux/oprofile.h             |    7 +
 10 files changed, 1567 insertions(+), 11 deletions(-)

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2011-02-15 11:10:20 +01:00
Heinz Graalfs 997dbb4967 oprofile, s390: Enhance OProfile to support System zs hardware sampling feature
OProfile is enhanced to export all files for controlling System z's
hardware sampling, and to invoke hwsampler exported functions to
initialize and use System z's hardware sampling.

The patch invokes hwsampler_setup() during oprofile init and exports
following hwsampler files under oprofilefs if hwsampler's setup
succeeded:

A new directory for hardware sampling based files

 /dev/oprofile/hwsampling/

The userland daemon must explicitly write to the following files
to disable (or enable) hardware based sampling

 /dev/oprofile/hwsampling/hwsampler

to modify the actual sampling rate

 /dev/oprofile/hwsampling/hw_interval

to modify the amount of sampling memory (measured in 4K pages)

 /dev/oprofile/hwsampling/hw_sdbt_blocks

The following files are read only and show
the possible minimum sampling rate

 /dev/oprofile/hwsampling/hw_min_interval

the possible maximum sampling rate

 /dev/oprofile/hwsampling/hw_max_interval

The patch splits the oprofile_timer_[init/exit] function so that it
can be also called through user context (oprofilefs) to avoid kernel
oops.

Applied with following changes:
* whitespace changes in Makefile and timer_int.c

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Maran Pakkirisamy <maranp@linux.vnet.ibm.com>
Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2011-02-15 11:08:50 +01:00
Heinz Graalfs 54ebbe7ba5 oprofile: Introduce new oprofile sample add function (oprofile_add_ext_hw_sample)
This patch introduces a new oprofile sample add function
(oprofile_add_ext_hw_sample) that can also take task_struct as an
argument, which is used by the hwsampler kernel module when copying
hardware samples to OProfile buffers.

Applied with following changes:
* removed #include <linux/module.h>
* whitespace changes
* removed conditional compilation (CONFIG_HAVE_HWSAMPLER)
* modified order of functions
* fix missing function definition in header file

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Maran Pakkirisamy <maranp@linux.vnet.ibm.com>
Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2011-02-15 11:07:07 +01:00
Linus Torvalds f02a38d86a Merge branches 'perf-fixes-for-linus' and 'x86-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:
  jump label: Add work around to i386 gcc asm goto bug
  x86, ftrace: Use safe noops, drop trap test
  jump_label: Fix unaligned traps on sparc.
  jump label: Make arch_jump_label_text_poke_early() optional
  jump label: Fix error with preempt disable holding mutex
  oprofile: Remove deprecated use of flush_scheduled_work()
  oprofile: Fix the hang while taking the cpu offline
  jump label: Fix deadlock b/w jump_label_mutex vs. text_mutex
  jump label: Fix module __init section race

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Check irq_remapped instead of remapping_enabled in destroy_irq()
2010-10-30 11:43:26 -07:00
Ingo Molnar 169ed55bd3 Merge branch 'tip/perf/jump-label-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/urgent 2010-10-30 10:43:08 +02:00
Tejun Heo 3d7851b3cd oprofile: Remove deprecated use of flush_scheduled_work()
flush_scheduled_work() is deprecated and scheduled to be removed.
sync_stop() currently cancels cpu_buffer works inside buffer_mutex and
flushes the system workqueue outside.  Instead, split end_cpu_work()
into two parts - stopping further work enqueues and flushing works -
and do the former inside buffer_mutex and latter outside.

For stable kernels v2.6.35.y and v2.6.36.y.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-29 11:54:18 +02:00
Santosh Shilimkar 4ac3dbec80 oprofile: Fix the hang while taking the cpu offline
The kernel build with CONFIG_OPROFILE and CPU_HOTPLUG enabled.
The oprofile is initialised using system timer in absence of hardware
counters supports. Oprofile isn't started from userland.

In this setup while doing a CPU offline the kernel hangs in infinite
for loop inside lock_hrtimer_base() function

This happens because as part of oprofile_cpu_notify(, it tries to
stop an hrtimer which was never started. These per-cpu hrtimers
are started when the oprfile is started.
	echo 1	> /dev/oprofile/enable

This problem also existwhen the cpu is booted with maxcpus parameter
set. When bringing the remaining cpus online the timers are started
even if oprofile is not yet enabled.

This patch fix this issue by adding a state variable so that
these hrtimer start/stop is only attempted when oprofile is
started

For stable kernels v2.6.35.y and v2.6.36.y.

Reported-by: Jan Sebastien <s-jan@ti.com>
Tested-by: sricharan <r.sricharan@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: stable@kernel.org
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-29 11:52:53 +02:00
Al Viro fc14f2fef6 convert get_sb_single() users
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:28 -04:00
Christoph Hellwig 85fe4025c6 fs: do not assign default i_ino in new_inode
Instead of always assigning an increasing inode number in new_inode
move the call to assign it into those callers that actually need it.
For now callers that need it is estimated conservatively, that is
the call is added to all filesystems that do not assign an i_ino
by themselves.  For a few more filesystems we can avoid assigning
any inode number given that they aren't user visible, and for others
it could be done lazily when an inode number is actually needed,
but that's left for later patches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25 21:26:11 -04:00
Linus Torvalds 092e0e7e52 Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
  vfs: make no_llseek the default
  vfs: don't use BKL in default_llseek
  llseek: automatically add .llseek fop
  libfs: use generic_file_llseek for simple_attr
  mac80211: disallow seeks in minstrel debug code
  lirc: make chardev nonseekable
  viotape: use noop_llseek
  raw: use explicit llseek file operations
  ibmasmfs: use generic_file_llseek
  spufs: use llseek in all file operations
  arm/omap: use generic_file_llseek in iommu_debug
  lkdtm: use generic_file_llseek in debugfs
  net/wireless: use generic_file_llseek in debugfs
  drm: use noop_llseek
2010-10-22 10:52:56 -07:00
Arnd Bergmann 6038f373a3 llseek: automatically add .llseek fop
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time.  Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
//   but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
   *off = E
|
   *off += E
|
   func(..., off, ...)
|
   E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
  *off = E
|
  *off += E
|
  func(..., off, ...)
|
  E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
 ...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
 .llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
 .read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
 .write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
 .open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
...  .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
...  .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
...  .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+	.llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
 .write = write_f,
 .read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
2010-10-15 15:53:27 +02:00
Robert Richter cd254f2952 oprofile: make !CONFIG_PM function stubs static inline
Make !CONFIG_PM function stubs static inline and remove section
attribute.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-15 12:47:18 +02:00
Anand Gadiyar b3b3a9b63f oprofile: fix linker errors
Commit e9677b3ce (oprofile, ARM: Use oprofile_arch_exit() to
cleanup on failure) caused oprofile_perf_exit to be called
in the cleanup path of oprofile_perf_init. The __exit tag
for oprofile_perf_exit should therefore be dropped.

The same has to be done for exit_driverfs as well, as this
function is called from oprofile_perf_exit. Else, we get
the following two linker errors.

  LD      .tmp_vmlinux1
`oprofile_perf_exit' referenced in section `.init.text' of arch/arm/oprofile/built-in.o: defined in discarded section `.exit.text' of arch/arm/oprofile/built-in.o
make: *** [.tmp_vmlinux1] Error 1

  LD      .tmp_vmlinux1
`exit_driverfs' referenced in section `.text' of arch/arm/oprofile/built-in.o: defined in discarded section `.exit.text' of arch/arm/oprofile/built-in.o
make: *** [.tmp_vmlinux1] Error 1

Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-15 12:45:44 +02:00
Anand Gadiyar 277dd98417 oprofile: include platform_device.h to fix build break
oprofile_perf.c needs to include platform_device.h
Otherwise we get the following build break.

  CC      arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.o
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:192: warning: 'struct platform_device' declared inside parameter list
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:192: warning: its scope is only this definition or declaration, which is probably not what you want
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:201: warning: 'struct platform_device' declared inside parameter list
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:210: error: variable 'oprofile_driver' has initializer but incomplete type
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:211: error: unknown field 'driver' specified in initializer
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:211: error: extra brace group at end of initializer
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:211: error: (near initialization for 'oprofile_driver')
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:213: warning: excess elements in struct initializer
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:213: warning: (near initialization for 'oprofile_driver')
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:214: error: unknown field 'resume' specified in initializer
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:214: warning: excess elements in struct initializer
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:214: warning: (near initialization for 'oprofile_driver')
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:215: error: unknown field 'suspend' specified in initializer
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:215: warning: excess elements in struct initializer
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:215: warning: (near initialization for 'oprofile_driver')
arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c: In function 'init_driverfs':

Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-15 12:45:44 +02:00
Robert Richter 6268464b37 Merge remote branch 'tip/perf/core' into oprofile/core
Conflicts:
	arch/arm/oprofile/common.c
	kernel/perf_event.c
2010-10-15 12:45:00 +02:00
Robert Richter 7df01d96b2 oprofile: disable write access to oprofilefs while profiler is running
Oprofile counters are setup when profiling is disabled. Thus, writing
to oprofilefs has no immediate effect. Changes are updated only after
oprofile is reenabled.

To keep userland and kernel states synchronized, we now allow
configuration of oprofile only if profiling is disabled.  In this case
it checks if the profiler is running and then disables write access to
oprofilefs by returning -EBUSY. The change should be backward
compatible with current oprofile userland daemon.

Acked-by: Maynard Johnson <maynardj@us.ibm.com>
Cc: William Cohen <wcohen@redhat.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-12 17:25:06 +02:00
Robert Richter 0361e02342 Merge branch 'oprofile/perf' into oprofile/core
Conflicts:
	arch/arm/oprofile/common.c

Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-11 19:38:39 +02:00
Robert Richter e9677b3ce2 oprofile, ARM: Use oprofile_arch_exit() to cleanup on failure
There is duplicate cleanup code in the init and exit functions. Now,
oprofile_arch_exit() is also used if oprofile_arch_init() fails.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-11 19:34:04 +02:00
Robert Richter 2bcb2b641a oprofile, ARM: Rework op_create_counter()
This patch simplifies op_create_counter(). Removing if/else if paths
and return code variable by direct returning from function.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-11 19:34:03 +02:00
Robert Richter 9c91283a19 oprofile, ARM: Remove some goto statements
This patch removes some unnecessary goto statements.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-11 19:34:03 +02:00
Robert Richter 81771974ae oprofile, ARM: Release resources on failure
This patch fixes a resource leak on failure, where the
oprofilefs and some counters may not released properly.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: <stable@kernel.org> # .35.x
LKML-Reference: <20100929145225.GJ13563@erda.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-11 19:27:10 +02:00
Robert Richter ad0f7cfaa8 Merge branch 'oprofile/urgent' (early part) into oprofile/perf 2010-10-11 19:26:50 +02:00
Matt Fleming 3d90a00763 oprofile: Abstract the perf-events backend
Move the perf-events backend from arch/arm/oprofile into
drivers/oprofile so that the code can be shared between architectures.

This allows each architecture to maintain only a single copy of the PMU
accessor functions instead of one for both perf and OProfile. It also
becomes possible for other architectures to delete much of their
OProfile code in favour of the common code now available in
drivers/oprofile/oprofile_perf.c.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-11 17:46:16 +02:00
Robert Richter 4fdaa7b682 oprofile: Remove duplicate code around __oprofilefs_create_file()
Removing duplicate code by assigning the inodes private data pointer
in __oprofilefs_create_file(). Extending the function interface to
pass the pointer.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-04 10:55:24 +02:00
Robert Richter ef70fcc0cd Merge branch 'oprofile/urgent' into oprofile/core
Conflicts:
	arch/arm/oprofile/common.c

Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-10-01 08:54:17 +02:00
Will Deacon 979048e1f2 oprofile: don't call arch exit code from init code on failure
oprofile_init calls oprofile_arch_init to initialise the architecture-specific
backend code. If this backend code returns failure, oprofile_arch_exit is
called immediately, making it difficult to allocate and free resources
correctly.

This patch removes the oprofile_arch_exit call from oprofile_init,
meaning that all architectures must ensure that oprofile_arch_init
cleans up any mess it's made before returning an error. As far as
I can tell, this only affects the code for ARM.

Cc: Robert Richter <robert.richter@amd.com>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-08-31 11:47:50 +02:00
Robert Richter 750d857c68 oprofile: fix crash when accessing freed task structs
This patch fixes a crash during shutdown reported below. The crash is
caused by accessing already freed task structs. The fix changes the
order for registering and unregistering notifier callbacks.

All notifiers must be initialized before buffers start working. To
stop buffer synchronization we cancel all workqueues, unregister the
notifier callback and then flush all buffers. After all of this we
finally can free all tasks listed.

This should avoid accessing freed tasks.

On 22.07.10 01:14:40, Benjamin Herrenschmidt wrote:

> So the initial observation is a spinlock bad magic followed by a crash
> in the spinlock debug code:
>
> [ 1541.586531] BUG: spinlock bad magic on CPU#5, events/5/136
> [ 1541.597564] Unable to handle kernel paging request for data at address 0x6b6b6b6b6b6b6d03
>
> Backtrace looks like:
>
>       spin_bug+0x74/0xd4
>       ._raw_spin_lock+0x48/0x184
>       ._spin_lock+0x10/0x24
>       .get_task_mm+0x28/0x8c
>       .sync_buffer+0x1b4/0x598
>       .wq_sync_buffer+0xa0/0xdc
>       .worker_thread+0x1d8/0x2a8
>       .kthread+0xa8/0xb4
>       .kernel_thread+0x54/0x70
>
> So we are accessing a freed task struct in the work queue when
> processing the samples.

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: stable@kernel.org
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-08-25 09:09:09 +02:00
Arnd Bergmann 729419f009 oprofile: make event buffer nonseekable
The event buffer cannot deal with seeks, so
we should forbid that outright.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Robert Richter <robert.richter@amd.com>
Cc: oprofile-list@lists.sf.net
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-07-26 10:58:24 +02:00
Phil Carmody 9414e99672 oprofile: protect from not being in an IRQ context
http://lkml.org/lkml/2010/4/27/285

Protect against dereferencing regs when it's NULL, and
force a magic number into pc to prevent too deep processing.
This approach permits the dropped samples to be tallied as
invalid Instruction Pointer events.

e.g. output from about 15mins at 10kHz sample rate:
Nr. samples received: 2565380
Nr. samples lost invalid pc: 4

Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-05-03 23:02:39 +02:00
Robert Richter b971f06187 Merge commit 'tip/tracing/core' into oprofile/core
Conflicts:
	drivers/oprofile/cpu_buffer.c

Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-04-23 16:47:51 +02:00
Andi Kleen cb6e943ccf oprofile: remove double ring buffering
oprofile used a double buffer scheme for its cpu event buffer
to avoid races on reading with the old locked ring buffer.

But that is obsolete now with the new ring buffer, so simply
use a single buffer. This greatly simplifies the code and avoids
a lot of sample drops on large runs, especially with call graph.

Based on suggestions from Steven Rostedt

For stable kernels from v2.6.32, but not earlier.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-04-23 15:30:38 +02:00
Robert Richter a36bf32e9e Merge commit 'v2.6.34-rc5' into oprofile/core 2010-04-23 14:30:22 +02:00
Ingo Molnar c1ab9cab75 Merge branch 'linus' into tracing/core
Conflicts:
	include/linux/module.h
	kernel/module.c

Semantic conflict:
	include/trace/events/module.h

Merge reason: Resolve the conflict with upstream commit 5fbfb18 ("Fix up
              possibly racy module refcounting")

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-08 10:18:47 +02:00
Steven Rostedt 66a8cb95ed ring-buffer: Add place holder recording of dropped events
Currently, when the ring buffer drops events, it does not record
the fact that it did so. It does inform the writer that the event
was dropped by returning a NULL event, but it does not put in any
place holder where the event was dropped.

This is not a trivial thing to add because the ring buffer mostly
runs in overwrite (flight recorder) mode. That is, when the ring
buffer is full, new data will overwrite old data.

In a produce/consumer mode, where new data is simply dropped when
the ring buffer is full, it is trivial to add the placeholder
for dropped events. When there's more room to write new data, then
a special event can be added to notify the reader about the dropped
events.

But in overwrite mode, any new write can overwrite events. A place
holder can not be inserted into the ring buffer since there never
may be room. A reader could also come in at anytime and miss the
placeholder.

Luckily, the way the ring buffer works, the read side can find out
if events were lost or not, and how many events. Everytime a write
takes place, if it overwrites the header page (the next read) it
updates a "overrun" variable that keeps track of the number of
lost events. When a reader swaps out a page from the ring buffer,
it can record this number, perfom the swap, and then check to
see if the number changed, and take the diff if it has, which would be
the number of events dropped. This can be stored by the reader
and returned to callers of the reader.

Since the reader page swap will fail if the writer moved the head
page since the time the reader page set up the swap, this gives room
to record the overruns without worrying about races. If the reader
sets up the pages, records the overrun, than performs the swap,
if the swap succeeds, then the overrun variable has not been
updated since the setup before the swap.

For binary readers of the ring buffer, a flag is set in the header
of each sub page (sub buffer) of the ring buffer. This flag is embedded
in the size field of the data on the sub buffer, in the 31st bit (the size
can be 32 or 64 bits depending on the architecture), but only 27
bits needs to be used for the actual size (less actually).

We could add a new field in the sub buffer header to also record the
number of events dropped since the last read, but this will change the
format of the binary ring buffer a bit too much. Perhaps this change can
be made if the information on the number of events dropped is considered
important enough.

Note, the notification of dropped events is only used by consuming reads
or peeking at the ring buffer. Iterating over the ring buffer does not
keep this information because the necessary data is only available when
a page swap is made, and the iterator does not swap out pages.

Cc: Robert Richter <robert.richter@amd.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lclaudio@uudg.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-03-31 22:57:04 -04:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Martin Schwidefsky bc078e4eab oprofile: convert oprofile from timer_hook to hrtimer
Oprofile is currently broken on systems running with NOHZ enabled.
A maximum of 1 tick is accounted via the timer_hook if a cpu sleeps
for a longer period of time. This does bad things to the percentages
in the profiler output. To solve this problem convert oprofile to
use a restarting hrtimer instead of the timer_hook.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-03-02 17:03:20 +01:00
Linus Torvalds d0316554d3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
  m68k: rename global variable vmalloc_end to m68k_vmalloc_end
  percpu: add missing per_cpu_ptr_to_phys() definition for UP
  percpu: Fix kdump failure if booted with percpu_alloc=page
  percpu: make misc percpu symbols unique
  percpu: make percpu symbols in ia64 unique
  percpu: make percpu symbols in powerpc unique
  percpu: make percpu symbols in x86 unique
  percpu: make percpu symbols in xen unique
  percpu: make percpu symbols in cpufreq unique
  percpu: make percpu symbols in oprofile unique
  percpu: make percpu symbols in tracer unique
  percpu: make percpu symbols under kernel/ and mm/ unique
  percpu: remove some sparse warnings
  percpu: make alloc_percpu() handle array types
  vmalloc: fix use of non-existent percpu variable in put_cpu_var()
  this_cpu: Use this_cpu_xx in trace_functions_graph.c
  this_cpu: Use this_cpu_xx for ftrace
  this_cpu: Use this_cpu_xx in nmi handling
  this_cpu: Use this_cpu operations in RCU
  this_cpu: Use this_cpu ops for VM statistics
  ...

Fix up trivial (famous last words) global per-cpu naming conflicts in
	arch/x86/kvm/svm.c
	mm/slab.c
2009-12-14 09:58:24 -08:00
Tejun Heo b3e9f672b6 percpu: make percpu symbols in oprofile unique
This patch updates percpu related symbols in oprofile such that percpu
symbols are unique and don't clash with local symbols.  This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.

* drivers/oprofile/cpu_buffer.c: s/cpu_buffer/op_cpu_buffer/

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Robert Richter <robert.richter@amd.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
2009-10-29 22:34:13 +09:00
Robert Richter c0868934e5 oprofile: warn on freeing event buffer too early
A race shouldn't happen since all workqueues or handlers are canceled
or flushed before the event buffer is freed. A warning is triggered
now if the buffer is freed too early.

Also, this patch adds some comments about event buffer protection,
reworks some code and adds code to clear buffer_pos during alloc and
free of the event buffer.

Cc: David Rientjes <rientjes@google.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-10-09 21:32:05 +02:00
David Rientjes 066b3aa845 oprofile: fix race condition in event_buffer free
Looking at the 2.6.31-rc9 code, it appears there is a race condition
in the event_buffer cleanup code path (shutdown). This could lead to
kernel panic as some CPUs may be operating on the event buffer AFTER
it has been freed. The attached patch solves the problem and makes
sure CPUs check if the buffer is not NULL before they access it as
some may have been spinning on the mutex while the buffer was being
freed.

The race may happen if the buffer is freed during pending reads. But
it is not clear why there are races in add_event_entry() since all
workqueues or handlers are canceled or flushed before the event buffer
is freed.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-10-09 18:02:01 +02:00
Li Zefan 79f5599772 cpumask: use zalloc_cpumask_var() where possible
Remove open-coded zalloc_cpumask_var() and zalloc_cpumask_var_node().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-24 09:34:24 +09:30
Alexey Dobriyan b87221de6a const: mark remaining super_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Robert Richter 1b294f5960 oprofile: Adding switch counter to oprofile statistic variables
This patch moves the multiplexing switch counter from x86 code to
common oprofile statistic variables. Now the value will be available
and usable for all architectures. The initialization and
incrementation also moved to common code.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-07-20 16:43:21 +02:00
Robert Richter a5659d17ad oprofile: Grouping multiplexing code in oprof.c
This patch moves multiplexing code to a single section of code. This
reduces the use of #ifdefs especially within functions.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-07-20 16:43:19 +02:00
Robert Richter 16422a6e2d oprofile: Remove oprofile_multiplexing_init()
oprofile_multiplexing_init() can be removed when moving the
initialization of oprofile_time_slice to oprofile_create_files().

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-07-20 16:43:19 +02:00
Robert Richter afe1b50fe6 oprofile: Rename variable timeout_jiffies and move to oprofile_files.c
This patch renames timeout_jiffies into an oprofile specific name. The
macro MULTIPLEXING_TIMER_DEFAULT is changed too.

Also, since this variable is controlled using oprofilefs, its
definition is moved to oprofile_files.c.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-07-20 16:43:19 +02:00
Robert Richter 2051cade7c oprofile: oprofile_set_timeout(), return with error for invalid args
Return with -EINVAL for invalid parameters instead of setting the
default value in oprofile_set_timeout().

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-07-20 16:43:18 +02:00
Jason Yeh 4d4036e0e7 oprofile: Implement performance counter multiplexing
The number of hardware counters is limited. The multiplexing feature
enables OProfile to gather more events than counters are provided by
the hardware. This is realized by switching between events at an user
specified time interval.

A new file (/dev/oprofile/time_slice) is added for the user to specify
the timer interval in ms. If the number of events to profile is higher
than the number of hardware counters available, the patch will
schedule a work queue that switches the event counter and re-writes
the different sets of values into it. The switching mechanism needs to
be implemented for each architecture to support multiplexing. This
patch only implements AMD CPU support, but multiplexing can be easily
extended for other models and architectures.

There are follow-on patches that rework parts of this patch.

Signed-off-by: Jason Yeh <jason.yeh@amd.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-07-20 16:33:53 +02:00
Robert Richter debc6a6927 Merge commit 'v2.6.31-rc3'; commit 'tip/oprofile' into oprofile/core
Conflicts:
	drivers/oprofile/oprofile_stats.c
	drivers/usb/otg/Kconfig
	drivers/usb/otg/Makefile

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-07-14 15:20:44 +02:00
Maynard Johnson 2b8777ca0c oprofile: reset bt_lost_no_mapping with other stats
The bt_lost_no_mapping is not getting reset at the start of a
profiling run, thus the oprofiled.log shows erroneous values for this
statistic. The attached patch fixes this problem.

Signed-off-by: Maynard Johnson <maynardj@us.ibm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-10 12:35:36 +02:00
Robert Richter b72f7fa978 Merge branches 'oprofile/fixes', 'oprofile/next' and 'oprofile/master' into oprofile/auto 2009-06-12 18:46:35 +02:00
Maynard Johnson 1cc4ce6f5f oprofile: reset bt_lost_no_mapping with other stats
The bt_lost_no_mapping is not getting reset at the start of a
profiling run, thus the oprofiled.log shows erroneous values for this
statistic. The attached patch fixes this problem.

Signed-off-by: Maynard Johnson <maynardj@us.ibm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-06-12 17:25:43 +02:00
Robert Richter 51563a0e56 x86/oprofile: introduce oprofile_add_data64()
The IBS implemention writes 64 bit register values to the cpu buffer
by writing two 32 values using oprofile_add_data(). This patch
introduces oprofile_add_data64() to write a single 64 bit value to the
buffer.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-06-11 20:16:00 +02:00
Robert Richter fecfe6320b oprofile: remove obselete include headers
This became obsolete with this commit:

 6dad828 oprofile: port to the new ring_buffer

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-06-11 16:10:12 +02:00
Robert Richter 54f2c841fa oprofile: fix cpu buffer size
The unit of oprofile_cpu_buffer_size is in samples, but was allocated
in bytes. This led to the allocation of too small cpu buffers. This
patch recalculates the buffer size in bytes taking also the
ring_buffer_event header size into account.

Reported-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-05-07 17:28:59 +02:00
Linus Torvalds 714f83d5d9 Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (413 commits)
  tracing, net: fix net tree and tracing tree merge interaction
  tracing, powerpc: fix powerpc tree and tracing tree interaction
  ring-buffer: do not remove reader page from list on ring buffer free
  function-graph: allow unregistering twice
  trace: make argument 'mem' of trace_seq_putmem() const
  tracing: add missing 'extern' keywords to trace_output.h
  tracing: provide trace_seq_reserve()
  blktrace: print out BLK_TN_MESSAGE properly
  blktrace: extract duplidate code
  blktrace: fix memory leak when freeing struct blk_io_trace
  blktrace: fix blk_probes_ref chaos
  blktrace: make classic output more classic
  blktrace: fix off-by-one bug
  blktrace: fix the original blktrace
  blktrace: fix a race when creating blk_tree_root in debugfs
  blktrace: fix timestamp in binary output
  tracing, Text Edit Lock: cleanup
  tracing: filter fix for TRACE_EVENT_FORMAT events
  ftrace: Using FTRACE_WARN_ON() to check "freed record" in ftrace_release()
  x86: kretprobe-booster interrupt emulation code fix
  ...

Fix up trivial conflicts in
 arch/parisc/include/asm/ftrace.h
 include/linux/memory.h
 kernel/extable.c
 kernel/module.c
2009-04-05 11:04:19 -07:00
Ingo Molnar 8302294f43 Merge branch 'tracing/core-v2' into tracing-for-linus
Conflicts:
	include/linux/slub_def.h
	lib/Kconfig.debug
	mm/slob.c
	mm/slub.c
2009-04-02 00:49:02 +02:00
Russell King bb75efddea oprofile: Thou shalt not call __exit functions from __init functions
Impact: fix ref to discarded function

`buffer_sync_cleanup' referenced in section `.init.text' of arch/arm/oprofile/built-in.o: defined in discarded section `.exit.text' of arch/arm/oprofile/built-in.o

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-30 22:05:18 +10:30
Ingo Molnar d95c357812 Merge branch 'x86/core' into cpus4096 2009-03-11 10:49:34 +01:00
Ingo Molnar f0ef039851 Merge branch 'x86/core' into tracing/textedit
Conflicts:
	arch/x86/Kconfig
	block/blktrace.c
	kernel/irq/handle.c

Semantic conflict:
	kernel/trace/blktrace.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-06 16:45:01 +01:00
Ingo Molnar 304cc6ae1b ring_buffer: remove unused flags parameter, fix
Oprofile's ring-buffer use was not considered.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-06 01:14:05 +01:00
Ingo Molnar 3ddeb51d9c Merge branch 'linus' into core/percpu
Conflicts:
	arch/x86/kernel/setup_percpu.c
2009-01-27 12:01:51 +01:00
Robert Richter 4c50d9ea9c cpumask: modifiy oprofile initialization
Delta patch to f7df8ed164 for
tip/cpus4096.

Moved initialization to sync_start()/sync_stop(). No changes needed in
buffer_sync.h and oprof.c anymore.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-22 14:37:06 +01:00
Robert Richter fdb6a8f4db oprofile: fix uninitialized use of struct op_entry
Impact: fix crash

In case of losing samples struct op_entry could have been used
uninitialized causing e.g. a wrong preemption count or NULL pointer
access. This patch fixes this.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-17 17:26:39 +01:00
Rusty Russell f7df8ed164 cpumask: convert misc driver functions
Impact: use new cpumask API.

Convert misc driver functions to use struct cpumask.

To Do:
  - Convert iucv_buffer_cpumask to cpumask_var_t.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Dean Nelson <dcn@sgi.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: oprofile-list@lists.sf.net
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: virtualization@lists.osdl.org
Cc: xen-devel@lists.xensource.com
Cc: Ursula Braun <ursula.braun@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
2009-01-11 19:12:52 +01:00
Linus Torvalds 4ce5f24193 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile: (31 commits)
  powerpc/oprofile: fix whitespaces in op_model_cell.c
  powerpc/oprofile: IBM CELL: add SPU event profiling support
  powerpc/oprofile: fix cell/pr_util.h
  powerpc/oprofile: IBM CELL: cleanup and restructuring
  oprofile: make new cpu buffer functions part of the api
  oprofile: remove #ifdef CONFIG_OPROFILE_IBS in non-ibs code
  ring_buffer: fix ring_buffer_event_length()
  oprofile: use new data sample format for ibs
  oprofile: add op_cpu_buffer_get_data()
  oprofile: add op_cpu_buffer_add_data()
  oprofile: rework implementation of cpu buffer events
  oprofile: modify op_cpu_buffer_read_entry()
  oprofile: add op_cpu_buffer_write_reserve()
  oprofile: rename variables in add_ibs_begin()
  oprofile: rename add_sample() in cpu_buffer.c
  oprofile: rename variable ibs_allowed to has_ibs in op_model_amd.c
  oprofile: making add_sample_entry() inline
  oprofile: remove backtrace code for ibs
  oprofile: remove unused ibs macro
  oprofile: remove unused components in struct oprofile_cpu_buffer
  ...
2009-01-09 12:43:06 -08:00
Robert Richter 14f0ca8eae oprofile: make new cpu buffer functions part of the api
This patch creates the new functions

 oprofile_write_reserve()
 oprofile_add_data()
 oprofile_write_commit()

and makes them part of the oprofile api.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:48:15 +01:00
Robert Richter ebf8d974e2 oprofile: remove #ifdef CONFIG_OPROFILE_IBS in non-ibs code
The ifdefs can be removed since the code is no longer ibs specific and
can be used for other purposes as well. IBS specific code is only in
op_model_amd.c.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:47:56 +01:00
Robert Richter 1acda878e2 oprofile: use new data sample format for ibs
The new ring buffer implementation allows the storage of samples with
different size. This patch implements the usage of the new sample
format to store ibs samples in the cpu buffer. Until now, writing to
the cpu buffer could lead to incomplete sampling sequences since IBS
samples were transfered in multiple samples. Due to a full buffer,
data could be lost at any time. This can't happen any more since the
complete data is reserved in advance and then stored in a single
sample.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:47:23 +01:00
Robert Richter bd7dc46f77 oprofile: add op_cpu_buffer_get_data()
This function provides access to attached data of a sample. It returns
the size of data including the current value. Also,
op_cpu_buffer_get_size() is available to check if there is data
attached.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:45:46 +01:00
Robert Richter d9928c25a6 oprofile: add op_cpu_buffer_add_data()
This function can be used to attach data to a sample. It returns the
remaining free buffer size that has been reserved with
op_cpu_buffer_write_reserve().

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:41:47 +01:00
Robert Richter ae735e9964 oprofile: rework implementation of cpu buffer events
Special events such as task or context switches are marked with an
escape code in the cpu buffer followed by an event code or a task
identifier. There is one escape code per event. To make escape
sequences also available for data samples the internal cpu buffer
format must be changed. The current implementation does not allow the
extension of event codes since this would lead to collisions with the
task identifiers. To avoid this, this patch introduces an event mask
that allows the storage of multiple events with one escape code. Now,
task identifiers are stored in the data section of the sample. The
implementation also allows the usage of custom data in a sample. As a
side effect the new code is much more readable and easier to
understand.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:40:47 +01:00
Robert Richter 2d87b14cf8 oprofile: modify op_cpu_buffer_read_entry()
This implements the support of samples with attached data.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:40:02 +01:00
Robert Richter 2cc28b9f26 oprofile: add op_cpu_buffer_write_reserve()
This function prepares the cpu buffer to write a sample.

Struct op_entry is used during operations on the ring buffer while
struct op_sample contains the data that is stored in the ring
buffer. Struct entry can be uninitialized. The function reserves a
data array that is specified by size. Use op_cpu_buffer_write_commit()
after preparing the sample. In case of errors a null pointer is
returned, otherwise the pointer to the sample.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:37:44 +01:00
Robert Richter d358e75fc4 oprofile: rename variables in add_ibs_begin()
This unifies usage of variable names within oprofile.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:35:42 +01:00
Robert Richter d0e233846d oprofile: rename add_sample() in cpu_buffer.c
Rename the fucntion to op_add_sample() since there is a collision with
another one with the same name in buffer_sync.c.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:35:26 +01:00
Robert Richter 6368a1f4d9 oprofile: making add_sample_entry() inline
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 17:06:47 +01:00
Robert Richter 8350c78734 oprofile: remove backtrace code for ibs
This code is broken since a TRACE_BEGIN_CODE is never sent to the
daemon. The data becomes corrupt since the backtrace is interpreted as
ibs sample.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 17:06:32 +01:00
Robert Richter f4ff236441 oprofile: remove unused ibs macro
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 17:06:16 +01:00
Robert Richter 8d15df84a4 oprofile: remove unused components in struct oprofile_cpu_buffer
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 17:06:00 +01:00
Robert Richter dbe6e2835e oprofile: simplify add_ibs_begin()
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 17:05:44 +01:00
Al Viro 56ff5efad9 zero i_uid/i_gid on inode allocation
... and don't bother in callers.  Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.

i_mode is not worth the effort; it has no common default value.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-05 11:54:28 -05:00
Nick Piggin c2452f3278 shrink struct dentry
struct dentry is one of the most critical structures in the kernel. So it's
sad to see it going neglected.

With CONFIG_PROFILING turned on (which is probably the common case at least
for distros and kernel developers), sizeof(struct dcache) == 208 here
(64-bit). This gives 19 objects per slab.

I packed d_mounted into a hole, and took another 4 bytes off the inline
name length to take the padding out from the end of the structure. This
shinks it to 200 bytes. I could have gone the other way and increased the
length to 40, but I'm aiming for a magic number, read on...

I then got rid of the d_cookie pointer. This shrinks it to 192 bytes. Rant:
why was this ever a good idea? The cookie system should increase its hash
size or use a tree or something if lookups are a problem. Also the "fast
dcookie lookups" in oprofile should be moved into the dcookie code -- how
can oprofile possibly care about the dcookie_mutex? It gets dropped after
get_dcookie() returns so it can't be providing any sort of protection.

At 192 bytes, 21 objects fit into a 4K page, saving about 3MB on my system
with ~140 000 entries allocated. 192 is also a multiple of 64, so we get
nice cacheline alignment on 64 and 32 byte line systems -- any given dentry
will now require 3 cachelines to touch all fields wheras previously it
would require 4.

I know the inline name size was chosen quite carefully, however with the
reduction in cacheline footprint, it should actually be just about as fast
to do a name lookup for a 36 character name as it was before the patch (and
faster for other sizes). The memory footprint savings for names which are
<= 32 or > 36 bytes long should more than make up for the memory cost for
33-36 byte names.

Performance is a feature...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:38 -05:00
Robert Richter 3967e93e06 oprofile: simplify add_sample() in cpu_buffer.c
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-30 05:30:05 +01:00
Robert Richter 6352d92dec oprofile: simplify oprofile_begin_trace()
This patch removes the unused return parameter in
oprofile_begin_trace(). Also, oprofile_begin_trace() and
oprofile_end_trace() are inline now.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29 18:54:44 +01:00
Robert Richter 317f33bce6 oprofile: simplify sync_buffer()
Make code more readable. No functional changes.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29 18:53:40 +01:00
Robert Richter 9741b309bb oprofile: simplify add_sample()
This patch removes add_us_sample() and simplifies add_sample(). Code
is much more readable now.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29 18:53:26 +01:00
Robert Richter d45d23bed4 oprofile: add inline function __oprofile_add_ext_sample()
This patch adds the inline function __oprofile_add_ext_sample() to
cpu_buffer.c and thus reduces overhead when calling
oprofile_add_sample().

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29 18:51:39 +01:00
Robert Richter 300157768f oprofile: reordering some code in cpu_buffer.c
Reordering code to keep alloc/free functions together.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29 17:24:36 +01:00
Robert Richter 9966718dae oprofile: remove ring buffer inline functions in cpu_buffer.h
This patch moves ring buffer inline functions to cpu_buffer.c.

Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29 15:19:19 +01:00
Robert Richter 6d2c53f3cd oprofile: rename cpu buffer functions
This patch renames cpu buffer functions to something more oprofile
specific names. Functions will be moved to the global name space.

Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29 15:17:52 +01:00
Robert Richter bd2172f580 oprofile: rename kernel-wide identifiers
This patch renames kernel-wide identifiers to something more oprofile
specific names.

Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-16 17:52:49 +01:00
Robert Richter 211117ff09 oprofile: fix lost sample counter
The number of lost samples could be greater than the number of
received samples. This patches fixes this. The implementation
introduces return values for add_sample() and add_code().

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 20:25:15 +01:00
Robert Richter 1d7503b5dc oprofile: remove nr_available_slots()
This function is no longer available after the port to the new ring
buffer. Its removal can lead to incomplete sampling sequences since
IBS samples and backtraces are transfered in multiple samples. Due to
a full buffer, samples could be lost any time. The userspace daemon
has to live with such incomplete sampling sequences as long as the
data within one sample is consistent.

This will be fixed by changing the internal buffer data there all data
of one IBS sample or a backtrace is packed in a single ring buffer
entry. This is possible since the new ring buffer supports variable
data size.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 20:03:35 +01:00
Robert Richter 6dad828b76 oprofile: port to the new ring_buffer
This patch replaces the current oprofile cpu buffer implementation
with the ring buffer provided by the tracing framework. The motivation
here is to leave the pain of implementing ring buffers to others. Oh,
no, there are more advantages. Main reason is the support of different
sample sizes that could be stored in the buffer. Use cases for this
are IBS and Cell spu profiling. Using the new ring buffer ensures
valid and complete samples and allows copying the cpu buffer stateless
without knowing its content. Second it will use generic kernel API and
also reduce code size. And hopefully, there are less bugs.

Since the new tracing ring buffer implementation uses spin locks to
protect the buffer during read/write access, it is difficult to use
the buffer in an NMI handler. In this case, writing to the buffer by
the NMI handler (x86) could occur also during critical sections when
reading the buffer. To avoid this, there are 2 buffers for independent
read and write access. Read access is in process context only, write
access only in the NMI handler. If the read buffer runs empty, both
buffers are swapped atomically. There is potentially a small window
during swapping where the buffers are disabled and samples could be
lost.

Using 2 buffers is a little bit overhead, but the solution is clear
and does not require changes in the ring buffer implementation. It can
be changed to a single buffer solution when the ring buffer access is
implemented as non-locking atomic code.

The new buffer requires more size to store the same amount of samples
because each sample includes an u32 header. Also, there is more code
to execute for buffer access. Nonetheless, the buffer implementation
is proven in the ftrace environment and worth to use also in oprofile.

Patches that changes the internal IBS buffer usage will follow.

Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 14:20:18 +01:00
Robert Richter fbc9bf9f0e oprofile: moving cpu_buffer_reset() to cpu_buffer.h
This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 14:20:16 +01:00
Robert Richter bf589e3296 oprofile: adding cpu_buffer_entries()
This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 14:20:15 +01:00
Robert Richter 229234ae4a oprofile: adding cpu_buffer_write_commit()
This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 14:20:14 +01:00
Robert Richter 7d468abee0 oprofile: adding cpu buffer r/w access functions
This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 14:20:13 +01:00
Robert Richter 37ca5eb341 oprofile: set values to default when creating oprofilefs
This patch restores default values for:

/dev/oprofile/cpu_buffer_size
/dev/oprofile/buffer_watershed
/dev/oprofile/buffer_size

when creating the oprofilefs:

 # opcontrol --deinit
 # opcontrol --init
 # cat /dev/oprofile/cpu_buffer_size
 8192
 # echo 5123 > /dev/oprofile/cpu_buffer_size
 # cat /dev/oprofile/cpu_buffer_size
 5123
 # opcontrol --deinit
 # opcontrol --init
 # cat /dev/oprofile/cpu_buffer_size
 8192
 # opcontrol --deinit

This sets the values in a defined state. Before, there was no way to
restore the defaults without rebooting the system or reloading the
module.

Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 14:20:10 +01:00