Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

16 files changed, 3530 insertions, 0 deletions

diff --git a/drivers/oprofile/COPYING b/drivers/oprofile/COPYING
new file mode 100755
index 00000000..d60c31a9
--- /dev/null
+++ b/drivers/oprofile/COPYING
@@ -0,0 +1,340 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+		    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+			    NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+		     END OF TERMS AND CONDITIONS
+
+	    How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year  name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
new file mode 100644
index 00000000..f34b5b29
--- /dev/null
+++ b/drivers/oprofile/buffer_sync.c
@@ -0,0 +1,598 @@
+/**
+ * @file buffer_sync.c
+ *
+ * @remark Copyright 2002-2009 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ * @author Barry Kasindorf
+ * @author Robert Richter <robert.richter@amd.com>
+ *
+ * This is the core of the buffer management. Each
+ * CPU buffer is processed and entered into the
+ * global event buffer. Such processing is necessary
+ * in several circumstances, mentioned below.
+ *
+ * The processing does the job of converting the
+ * transitory EIP value into a persistent dentry/offset
+ * value that the profiler can record at its leisure.
+ *
+ * See fs/dcookies.c for a description of the dentry/offset
+ * objects.
+ */
+
+#include <linux/mm.h>
+#include <linux/workqueue.h>
+#include <linux/notifier.h>
+#include <linux/dcookies.h>
+#include <linux/profile.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/oprofile.h>
+#include <linux/sched.h>
+#include <linux/gfp.h>
+
+#include "oprofile_stats.h"
+#include "event_buffer.h"
+#include "cpu_buffer.h"
+#include "buffer_sync.h"
+
+static LIST_HEAD(dying_tasks);
+static LIST_HEAD(dead_tasks);
+static cpumask_var_t marked_cpus;
+static DEFINE_SPINLOCK(task_mortuary);
+static void process_task_mortuary(void);
+
+/* Take ownership of the task struct and place it on the
+ * list for processing. Only after two full buffer syncs
+ * does the task eventually get freed, because by then
+ * we are sure we will not reference it again.
+ * Can be invoked from softirq via RCU callback due to
+ * call_rcu() of the task struct, hence the _irqsave.
+ */
+static int
+task_free_notify(struct notifier_block *self, unsigned long val, void *data)
+{
+	unsigned long flags;
+	struct task_struct *task = data;
+	spin_lock_irqsave(&task_mortuary, flags);
+	list_add(&task->tasks, &dying_tasks);
+	spin_unlock_irqrestore(&task_mortuary, flags);
+	return NOTIFY_OK;
+}
+
+
+/* The task is on its way out. A sync of the buffer means we can catch
+ * any remaining samples for this task.
+ */
+static int
+task_exit_notify(struct notifier_block *self, unsigned long val, void *data)
+{
+	/* To avoid latency problems, we only process the current CPU,
+	 * hoping that most samples for the task are on this CPU
+	 */
+	sync_buffer(raw_smp_processor_id());
+	return 0;
+}
+
+
+/* The task is about to try a do_munmap(). We peek at what it's going to
+ * do, and if it's an executable region, process the samples first, so
+ * we don't lose any. This does not have to be exact, it's a QoI issue
+ * only.
+ */
+static int
+munmap_notify(struct notifier_block *self, unsigned long val, void *data)
+{
+	unsigned long addr = (unsigned long)data;
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *mpnt;
+
+	down_read(&mm->mmap_sem);
+
+	mpnt = find_vma(mm, addr);
+	if (mpnt && mpnt->vm_file && (mpnt->vm_flags & VM_EXEC)) {
+		up_read(&mm->mmap_sem);
+		/* To avoid latency problems, we only process the current CPU,
+		 * hoping that most samples for the task are on this CPU
+		 */
+		sync_buffer(raw_smp_processor_id());
+		return 0;
+	}
+
+	up_read(&mm->mmap_sem);
+	return 0;
+}
+
+
+/* We need to be told about new modules so we don't attribute to a previously
+ * loaded module, or drop the samples on the floor.
+ */
+static int
+module_load_notify(struct notifier_block *self, unsigned long val, void *data)
+{
+#ifdef CONFIG_MODULES
+	if (val != MODULE_STATE_COMING)
+		return 0;
+
+	/* FIXME: should we process all CPU buffers ? */
+	mutex_lock(&buffer_mutex);
+	add_event_entry(ESCAPE_CODE);
+	add_event_entry(MODULE_LOADED_CODE);
+	mutex_unlock(&buffer_mutex);
+#endif
+	return 0;
+}
+
+
+static struct notifier_block task_free_nb = {
+	.notifier_call	= task_free_notify,
+};
+
+static struct notifier_block task_exit_nb = {
+	.notifier_call	= task_exit_notify,
+};
+
+static struct notifier_block munmap_nb = {
+	.notifier_call	= munmap_notify,
+};
+
+static struct notifier_block module_load_nb = {
+	.notifier_call = module_load_notify,
+};
+
+static void free_all_tasks(void)
+{
+	/* make sure we don't leak task structs */
+	process_task_mortuary();
+	process_task_mortuary();
+}
+
+int sync_start(void)
+{
+	int err;
+
+	if (!zalloc_cpumask_var(&marked_cpus, GFP_KERNEL))
+		return -ENOMEM;
+
+	err = task_handoff_register(&task_free_nb);
+	if (err)
+		goto out1;
+	err = profile_event_register(PROFILE_TASK_EXIT, &task_exit_nb);
+	if (err)
+		goto out2;
+	err = profile_event_register(PROFILE_MUNMAP, &munmap_nb);
+	if (err)
+		goto out3;
+	err = register_module_notifier(&module_load_nb);
+	if (err)
+		goto out4;
+
+	start_cpu_work();
+
+out:
+	return err;
+out4:
+	profile_event_unregister(PROFILE_MUNMAP, &munmap_nb);
+out3:
+	profile_event_unregister(PROFILE_TASK_EXIT, &task_exit_nb);
+out2:
+	task_handoff_unregister(&task_free_nb);
+	free_all_tasks();
+out1:
+	free_cpumask_var(marked_cpus);
+	goto out;
+}
+
+
+void sync_stop(void)
+{
+	end_cpu_work();
+	unregister_module_notifier(&module_load_nb);
+	profile_event_unregister(PROFILE_MUNMAP, &munmap_nb);
+	profile_event_unregister(PROFILE_TASK_EXIT, &task_exit_nb);
+	task_handoff_unregister(&task_free_nb);
+	barrier();			/* do all of the above first */
+
+	flush_cpu_work();
+
+	free_all_tasks();
+	free_cpumask_var(marked_cpus);
+}
+
+
+/* Optimisation. We can manage without taking the dcookie sem
+ * because we cannot reach this code without at least one
+ * dcookie user still being registered (namely, the reader
+ * of the event buffer). */
+static inline unsigned long fast_get_dcookie(struct path *path)
+{
+	unsigned long cookie;
+
+	if (path->dentry->d_flags & DCACHE_COOKIE)
+		return (unsigned long)path->dentry;
+	get_dcookie(path, &cookie);
+	return cookie;
+}
+
+
+/* Look up the dcookie for the task's first VM_EXECUTABLE mapping,
+ * which corresponds loosely to "application name". This is
+ * not strictly necessary but allows oprofile to associate
+ * shared-library samples with particular applications
+ */
+static unsigned long get_exec_dcookie(struct mm_struct *mm)
+{
+	unsigned long cookie = NO_COOKIE;
+	struct vm_area_struct *vma;
+
+	if (!mm)
+		goto out;
+
+	for (vma = mm->mmap; vma; vma = vma->vm_next) {
+		if (!vma->vm_file)
+			continue;
+		if (!(vma->vm_flags & VM_EXECUTABLE))
+			continue;
+		cookie = fast_get_dcookie(&vma->vm_file->f_path);
+		break;
+	}
+
+out:
+	return cookie;
+}
+
+
+/* Convert the EIP value of a sample into a persistent dentry/offset
+ * pair that can then be added to the global event buffer. We make
+ * sure to do this lookup before a mm->mmap modification happens so
+ * we don't lose track.
+ */
+static unsigned long
+lookup_dcookie(struct mm_struct *mm, unsigned long addr, off_t *offset)
+{
+	unsigned long cookie = NO_COOKIE;
+	struct vm_area_struct *vma;
+
+	for (vma = find_vma(mm, addr); vma; vma = vma->vm_next) {
+
+		if (addr < vma->vm_start || addr >= vma->vm_end)
+			continue;
+
+		if (vma->vm_file) {
+			cookie = fast_get_dcookie(&vma->vm_file->f_path);
+			*offset = (vma->vm_pgoff << PAGE_SHIFT) + addr -
+				vma->vm_start;
+		} else {
+			/* must be an anonymous map */
+			*offset = addr;
+		}
+
+		break;
+	}
+
+	if (!vma)
+		cookie = INVALID_COOKIE;
+
+	return cookie;
+}
+
+static unsigned long last_cookie = INVALID_COOKIE;
+
+static void add_cpu_switch(int i)
+{
+	add_event_entry(ESCAPE_CODE);
+	add_event_entry(CPU_SWITCH_CODE);
+	add_event_entry(i);
+	last_cookie = INVALID_COOKIE;
+}
+
+static void add_kernel_ctx_switch(unsigned int in_kernel)
+{
+	add_event_entry(ESCAPE_CODE);
+	if (in_kernel)
+		add_event_entry(KERNEL_ENTER_SWITCH_CODE);
+	else
+		add_event_entry(KERNEL_EXIT_SWITCH_CODE);
+}
+
+static void
+add_user_ctx_switch(struct task_struct const *task, unsigned long cookie)
+{
+	add_event_entry(ESCAPE_CODE);
+	add_event_entry(CTX_SWITCH_CODE);
+	add_event_entry(task->pid);
+	add_event_entry(cookie);
+	/* Another code for daemon back-compat */
+	add_event_entry(ESCAPE_CODE);
+	add_event_entry(CTX_TGID_CODE);
+	add_event_entry(task->tgid);
+}
+
+
+static void add_cookie_switch(unsigned long cookie)
+{
+	add_event_entry(ESCAPE_CODE);
+	add_event_entry(COOKIE_SWITCH_CODE);
+	add_event_entry(cookie);
+}
+
+
+static void add_trace_begin(void)
+{
+	add_event_entry(ESCAPE_CODE);
+	add_event_entry(TRACE_BEGIN_CODE);
+}
+
+static void add_data(struct op_entry *entry, struct mm_struct *mm)
+{
+	unsigned long code, pc, val;
+	unsigned long cookie;
+	off_t offset;
+
+	if (!op_cpu_buffer_get_data(entry, &code))
+		return;
+	if (!op_cpu_buffer_get_data(entry, &pc))
+		return;
+	if (!op_cpu_buffer_get_size(entry))
+		return;
+
+	if (mm) {
+		cookie = lookup_dcookie(mm, pc, &offset);
+
+		if (cookie == NO_COOKIE)
+			offset = pc;
+		if (cookie == INVALID_COOKIE) {
+			atomic_inc(&oprofile_stats.sample_lost_no_mapping);
+			offset = pc;
+		}
+		if (cookie != last_cookie) {
+			add_cookie_switch(cookie);
+			last_cookie = cookie;
+		}
+	} else
+		offset = pc;
+
+	add_event_entry(ESCAPE_CODE);
+	add_event_entry(code);
+	add_event_entry(offset);	/* Offset from Dcookie */
+
+	while (op_cpu_buffer_get_data(entry, &val))
+		add_event_entry(val);
+}
+
+static inline void add_sample_entry(unsigned long offset, unsigned long event)
+{
+	add_event_entry(offset);
+	add_event_entry(event);
+}
+
+
+/*
+ * Add a sample to the global event buffer. If possible the
+ * sample is converted into a persistent dentry/offset pair
+ * for later lookup from userspace. Return 0 on failure.
+ */
+static int
+add_sample(struct mm_struct *mm, struct op_sample *s, int in_kernel)
+{
+	unsigned long cookie;
+	off_t offset;
+
+	if (in_kernel) {
+		add_sample_entry(s->eip, s->event);
+		return 1;
+	}
+
+	/* add userspace sample */
+
+	if (!mm) {
+		atomic_inc(&oprofile_stats.sample_lost_no_mm);
+		return 0;
+	}
+
+	cookie = lookup_dcookie(mm, s->eip, &offset);
+
+	if (cookie == INVALID_COOKIE) {
+		atomic_inc(&oprofile_stats.sample_lost_no_mapping);
+		return 0;
+	}
+
+	if (cookie != last_cookie) {
+		add_cookie_switch(cookie);
+		last_cookie = cookie;
+	}
+
+	add_sample_entry(offset, s->event);
+
+	return 1;
+}
+
+
+static void release_mm(struct mm_struct *mm)
+{
+	if (!mm)
+		return;
+	up_read(&mm->mmap_sem);
+	mmput(mm);
+}
+
+
+static struct mm_struct *take_tasks_mm(struct task_struct *task)
+{
+	struct mm_struct *mm = get_task_mm(task);
+	if (mm)
+		down_read(&mm->mmap_sem);
+	return mm;
+}
+
+
+static inline int is_code(unsigned long val)
+{
+	return val == ESCAPE_CODE;
+}
+
+
+/* Move tasks along towards death. Any tasks on dead_tasks
+ * will definitely have no remaining references in any
+ * CPU buffers at this point, because we use two lists,
+ * and to have reached the list, it must have gone through
+ * one full sync already.
+ */
+static void process_task_mortuary(void)
+{
+	unsigned long flags;
+	LIST_HEAD(local_dead_tasks);
+	struct task_struct *task;
+	struct task_struct *ttask;
+
+	spin_lock_irqsave(&task_mortuary, flags);
+
+	list_splice_init(&dead_tasks, &local_dead_tasks);
+	list_splice_init(&dying_tasks, &dead_tasks);
+
+	spin_unlock_irqrestore(&task_mortuary, flags);
+
+	list_for_each_entry_safe(task, ttask, &local_dead_tasks, tasks) {
+		list_del(&task->tasks);
+		free_task(task);
+	}
+}
+
+
+static void mark_done(int cpu)
+{
+	int i;
+
+	cpumask_set_cpu(cpu, marked_cpus);
+
+	for_each_online_cpu(i) {
+		if (!cpumask_test_cpu(i, marked_cpus))
+			return;
+	}
+
+	/* All CPUs have been processed at least once,
+	 * we can process the mortuary once
+	 */
+	process_task_mortuary();
+
+	cpumask_clear(marked_cpus);
+}
+
+
+/* FIXME: this is not sufficient if we implement syscall barrier backtrace
+ * traversal, the code switch to sb_sample_start at first kernel enter/exit
+ * switch so we need a fifth state and some special handling in sync_buffer()
+ */
+typedef enum {
+	sb_bt_ignore = -2,
+	sb_buffer_start,
+	sb_bt_start,
+	sb_sample_start,
+} sync_buffer_state;
+
+/* Sync one of the CPU's buffers into the global event buffer.
+ * Here we need to go through each batch of samples punctuated
+ * by context switch notes, taking the task's mmap_sem and doing
+ * lookup in task->mm->mmap to convert EIP into dcookie/offset
+ * value.
+ */
+void sync_buffer(int cpu)
+{
+	struct mm_struct *mm = NULL;
+	struct mm_struct *oldmm;
+	unsigned long val;
+	struct task_struct *new;
+	unsigned long cookie = 0;
+	int in_kernel = 1;
+	sync_buffer_state state = sb_buffer_start;
+	unsigned int i;
+	unsigned long available;
+	unsigned long flags;
+	struct op_entry entry;
+	struct op_sample *sample;
+
+	mutex_lock(&buffer_mutex);
+
+	add_cpu_switch(cpu);
+
+	op_cpu_buffer_reset(cpu);
+	available = op_cpu_buffer_entries(cpu);
+
+	for (i = 0; i < available; ++i) {
+		sample = op_cpu_buffer_read_entry(&entry, cpu);
+		if (!sample)
+			break;
+
+		if (is_code(sample->eip)) {
+			flags = sample->event;
+			if (flags & TRACE_BEGIN) {
+				state = sb_bt_start;
+				add_trace_begin();
+			}
+			if (flags & KERNEL_CTX_SWITCH) {
+				/* kernel/userspace switch */
+				in_kernel = flags & IS_KERNEL;
+				if (state == sb_buffer_start)
+					state = sb_sample_start;
+				add_kernel_ctx_switch(flags & IS_KERNEL);
+			}
+			if (flags & USER_CTX_SWITCH
+			    && op_cpu_buffer_get_data(&entry, &val)) {
+				/* userspace context switch */
+				new = (struct task_struct *)val;
+				oldmm = mm;
+				release_mm(oldmm);
+				mm = take_tasks_mm(new);
+				if (mm != oldmm)
+					cookie = get_exec_dcookie(mm);
+				add_user_ctx_switch(new, cookie);
+			}
+			if (op_cpu_buffer_get_size(&entry))
+				add_data(&entry, mm);
+			continue;
+		}
+
+		if (state < sb_bt_start)
+			/* ignore sample */
+			continue;
+
+		if (add_sample(mm, sample, in_kernel))
+			continue;
+
+		/* ignore backtraces if failed to add a sample */
+		if (state == sb_bt_start) {
+			state = sb_bt_ignore;
+			atomic_inc(&oprofile_stats.bt_lost_no_mapping);
+		}
+	}
+	release_mm(mm);
+
+	mark_done(cpu);
+
+	mutex_unlock(&buffer_mutex);
+}
+
+/* The function can be used to add a buffer worth of data directly to
+ * the kernel buffer. The buffer is assumed to be a circular buffer.
+ * Take the entries from index start and end at index end, wrapping
+ * at max_entries.
+ */
+void oprofile_put_buff(unsigned long *buf, unsigned int start,
+		       unsigned int stop, unsigned int max)
+{
+	int i;
+
+	i = start;
+
+	mutex_lock(&buffer_mutex);
+	while (i != stop) {
+		add_event_entry(buf[i++]);
+
+		if (i >= max)
+			i = 0;
+	}
+
+	mutex_unlock(&buffer_mutex);
+}
+
diff --git a/drivers/oprofile/buffer_sync.h b/drivers/oprofile/buffer_sync.h
new file mode 100644
index 00000000..3110732c
--- /dev/null
+++ b/drivers/oprofile/buffer_sync.h
@@ -0,0 +1,22 @@
+/**
+ * @file buffer_sync.h
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#ifndef OPROFILE_BUFFER_SYNC_H
+#define OPROFILE_BUFFER_SYNC_H
+
+/* add the necessary profiling hooks */
+int sync_start(void);
+
+/* remove the hooks */
+void sync_stop(void);
+
+/* sync the given CPU's buffer */
+void sync_buffer(int cpu);
+
+#endif /* OPROFILE_BUFFER_SYNC_H */
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
new file mode 100644
index 00000000..b8ef8ddc
--- /dev/null
+++ b/drivers/oprofile/cpu_buffer.c
@@ -0,0 +1,468 @@
+/**
+ * @file cpu_buffer.c
+ *
+ * @remark Copyright 2002-2009 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ * @author Barry Kasindorf <barry.kasindorf@amd.com>
+ * @author Robert Richter <robert.richter@amd.com>
+ *
+ * Each CPU has a local buffer that stores PC value/event
+ * pairs. We also log context switches when we notice them.
+ * Eventually each CPU's buffer is processed into the global
+ * event buffer by sync_buffer().
+ *
+ * We use a local buffer for two reasons: an NMI or similar
+ * interrupt cannot synchronise, and high sampling rates
+ * would lead to catastrophic global synchronisation if
+ * a global buffer was used.
+ */
+
+#include <linux/sched.h>
+#include <linux/oprofile.h>
+#include <linux/errno.h>
+
+#include "event_buffer.h"
+#include "cpu_buffer.h"
+#include "buffer_sync.h"
+#include "oprof.h"
+
+#define OP_BUFFER_FLAGS	0
+
+static struct ring_buffer *op_ring_buffer;
+DEFINE_PER_CPU(struct oprofile_cpu_buffer, op_cpu_buffer);
+
+static void wq_sync_buffer(struct work_struct *work);
+
+#define DEFAULT_TIMER_EXPIRE (HZ / 10)
+static int work_enabled;
+
+unsigned long oprofile_get_cpu_buffer_size(void)
+{
+	return oprofile_cpu_buffer_size;
+}
+
+void oprofile_cpu_buffer_inc_smpl_lost(void)
+{
+	struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(op_cpu_buffer);
+
+	cpu_buf->sample_lost_overflow++;
+}
+
+void free_cpu_buffers(void)
+{
+	if (op_ring_buffer)
+		ring_buffer_free(op_ring_buffer);
+	op_ring_buffer = NULL;
+}
+
+#define RB_EVENT_HDR_SIZE 4
+
+int alloc_cpu_buffers(void)
+{
+	int i;
+
+	unsigned long buffer_size = oprofile_cpu_buffer_size;
+	unsigned long byte_size = buffer_size * (sizeof(struct op_sample) +
+						 RB_EVENT_HDR_SIZE);
+
+	op_ring_buffer = ring_buffer_alloc(byte_size, OP_BUFFER_FLAGS);
+	if (!op_ring_buffer)
+		goto fail;
+
+	for_each_possible_cpu(i) {
+		struct oprofile_cpu_buffer *b = &per_cpu(op_cpu_buffer, i);
+
+		b->last_task = NULL;
+		b->last_is_kernel = -1;
+		b->tracing = 0;
+		b->buffer_size = buffer_size;
+		b->sample_received = 0;
+		b->sample_lost_overflow = 0;
+		b->backtrace_aborted = 0;
+		b->sample_invalid_eip = 0;
+		b->cpu = i;
+		INIT_DELAYED_WORK(&b->work, wq_sync_buffer);
+	}
+	return 0;
+
+fail:
+	free_cpu_buffers();
+	return -ENOMEM;
+}
+
+void start_cpu_work(void)
+{
+	int i;
+
+	work_enabled = 1;
+
+	for_each_online_cpu(i) {
+		struct oprofile_cpu_buffer *b = &per_cpu(op_cpu_buffer, i);
+
+		/*
+		 * Spread the work by 1 jiffy per cpu so they dont all
+		 * fire at once.
+		 */
+		schedule_delayed_work_on(i, &b->work, DEFAULT_TIMER_EXPIRE + i);
+	}
+}
+
+void end_cpu_work(void)
+{
+	work_enabled = 0;
+}
+
+void flush_cpu_work(void)
+{
+	int i;
+
+	for_each_online_cpu(i) {
+		struct oprofile_cpu_buffer *b = &per_cpu(op_cpu_buffer, i);
+
+		/* these works are per-cpu, no need for flush_sync */
+		flush_delayed_work(&b->work);
+	}
+}
+
+/*
+ * 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.
+ *
+ */
+struct op_sample
+*op_cpu_buffer_write_reserve(struct op_entry *entry, unsigned long size)
+{
+	entry->event = ring_buffer_lock_reserve
+		(op_ring_buffer, sizeof(struct op_sample) +
+		 size * sizeof(entry->sample->data[0]));
+	if (!entry->event)
+		return NULL;
+	entry->sample = ring_buffer_event_data(entry->event);
+	entry->size = size;
+	entry->data = entry->sample->data;
+
+	return entry->sample;
+}
+
+int op_cpu_buffer_write_commit(struct op_entry *entry)
+{
+	return ring_buffer_unlock_commit(op_ring_buffer, entry->event);
+}
+
+struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu)
+{
+	struct ring_buffer_event *e;
+	e = ring_buffer_consume(op_ring_buffer, cpu, NULL, NULL);
+	if (!e)
+		return NULL;
+
+	entry->event = e;
+	entry->sample = ring_buffer_event_data(e);
+	entry->size = (ring_buffer_event_length(e) - sizeof(struct op_sample))
+		/ sizeof(entry->sample->data[0]);
+	entry->data = entry->sample->data;
+	return entry->sample;
+}
+
+unsigned long op_cpu_buffer_entries(int cpu)
+{
+	return ring_buffer_entries_cpu(op_ring_buffer, cpu);
+}
+
+static int
+op_add_code(struct oprofile_cpu_buffer *cpu_buf, unsigned long backtrace,
+	    int is_kernel, struct task_struct *task)
+{
+	struct op_entry entry;
+	struct op_sample *sample;
+	unsigned long flags;
+	int size;
+
+	flags = 0;
+
+	if (backtrace)
+		flags |= TRACE_BEGIN;
+
+	/* notice a switch from user->kernel or vice versa */
+	is_kernel = !!is_kernel;
+	if (cpu_buf->last_is_kernel != is_kernel) {
+		cpu_buf->last_is_kernel = is_kernel;
+		flags |= KERNEL_CTX_SWITCH;
+		if (is_kernel)
+			flags |= IS_KERNEL;
+	}
+
+	/* notice a task switch */
+	if (cpu_buf->last_task != task) {
+		cpu_buf->last_task = task;
+		flags |= USER_CTX_SWITCH;
+	}
+
+	if (!flags)
+		/* nothing to do */
+		return 0;
+
+	if (flags & USER_CTX_SWITCH)
+		size = 1;
+	else
+		size = 0;
+
+	sample = op_cpu_buffer_write_reserve(&entry, size);
+	if (!sample)
+		return -ENOMEM;
+
+	sample->eip = ESCAPE_CODE;
+	sample->event = flags;
+
+	if (size)
+		op_cpu_buffer_add_data(&entry, (unsigned long)task);
+
+	op_cpu_buffer_write_commit(&entry);
+
+	return 0;
+}
+
+static inline int
+op_add_sample(struct oprofile_cpu_buffer *cpu_buf,
+	      unsigned long pc, unsigned long event)
+{
+	struct op_entry entry;
+	struct op_sample *sample;
+
+	sample = op_cpu_buffer_write_reserve(&entry, 0);
+	if (!sample)
+		return -ENOMEM;
+
+	sample->eip = pc;
+	sample->event = event;
+
+	return op_cpu_buffer_write_commit(&entry);
+}
+
+/*
+ * This must be safe from any context.
+ *
+ * is_kernel is needed because on some architectures you cannot
+ * tell if you are in kernel or user space simply by looking at
+ * pc. We tag this in the buffer by generating kernel enter/exit
+ * events whenever is_kernel changes
+ */
+static int
+log_sample(struct oprofile_cpu_buffer *cpu_buf, unsigned long pc,
+	   unsigned long backtrace, int is_kernel, unsigned long event,
+	   struct task_struct *task)
+{
+	struct task_struct *tsk = task ? task : current;
+	cpu_buf->sample_received++;
+
+	if (pc == ESCAPE_CODE) {
+		cpu_buf->sample_invalid_eip++;
+		return 0;
+	}
+
+	if (op_add_code(cpu_buf, backtrace, is_kernel, tsk))
+		goto fail;
+
+	if (op_add_sample(cpu_buf, pc, event))
+		goto fail;
+
+	return 1;
+
+fail:
+	cpu_buf->sample_lost_overflow++;
+	return 0;
+}
+
+static inline void oprofile_begin_trace(struct oprofile_cpu_buffer *cpu_buf)
+{
+	cpu_buf->tracing = 1;
+}
+
+static inline void oprofile_end_trace(struct oprofile_cpu_buffer *cpu_buf)
+{
+	cpu_buf->tracing = 0;
+}
+
+static inline void
+__oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
+			  unsigned long event, int is_kernel,
+			  struct task_struct *task)
+{
+	struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(op_cpu_buffer);
+	unsigned long backtrace = oprofile_backtrace_depth;
+
+	/*
+	 * if log_sample() fail we can't backtrace since we lost the
+	 * source of this event
+	 */
+	if (!log_sample(cpu_buf, pc, backtrace, is_kernel, event, task))
+		/* failed */
+		return;
+
+	if (!backtrace)
+		return;
+
+	oprofile_begin_trace(cpu_buf);
+	oprofile_ops.backtrace(regs, backtrace);
+	oprofile_end_trace(cpu_buf);
+}
+
+void oprofile_add_ext_hw_sample(unsigned long pc, struct pt_regs * const regs,
+				unsigned long event, int is_kernel,
+				struct task_struct *task)
+{
+	__oprofile_add_ext_sample(pc, regs, event, is_kernel, task);
+}
+
+void oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
+			     unsigned long event, int is_kernel)
+{
+	__oprofile_add_ext_sample(pc, regs, event, is_kernel, NULL);
+}
+
+void oprofile_add_sample(struct pt_regs * const regs, unsigned long event)
+{
+	int is_kernel;
+	unsigned long pc;
+
+	if (likely(regs)) {
+		is_kernel = !user_mode(regs);
+		pc = profile_pc(regs);
+	} else {
+		is_kernel = 0;    /* This value will not be used */
+		pc = ESCAPE_CODE; /* as this causes an early return. */
+	}
+
+	__oprofile_add_ext_sample(pc, regs, event, is_kernel, NULL);
+}
+
+/*
+ * Add samples with data to the ring buffer.
+ *
+ * Use oprofile_add_data(&entry, val) to add data and
+ * oprofile_write_commit(&entry) to commit the sample.
+ */
+void
+oprofile_write_reserve(struct op_entry *entry, struct pt_regs * const regs,
+		       unsigned long pc, int code, int size)
+{
+	struct op_sample *sample;
+	int is_kernel = !user_mode(regs);
+	struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(op_cpu_buffer);
+
+	cpu_buf->sample_received++;
+
+	/* no backtraces for samples with data */
+	if (op_add_code(cpu_buf, 0, is_kernel, current))
+		goto fail;
+
+	sample = op_cpu_buffer_write_reserve(entry, size + 2);
+	if (!sample)
+		goto fail;
+	sample->eip = ESCAPE_CODE;
+	sample->event = 0;		/* no flags */
+
+	op_cpu_buffer_add_data(entry, code);
+	op_cpu_buffer_add_data(entry, pc);
+
+	return;
+
+fail:
+	entry->event = NULL;
+	cpu_buf->sample_lost_overflow++;
+}
+
+int oprofile_add_data(struct op_entry *entry, unsigned long val)
+{
+	if (!entry->event)
+		return 0;
+	return op_cpu_buffer_add_data(entry, val);
+}
+
+int oprofile_add_data64(struct op_entry *entry, u64 val)
+{
+	if (!entry->event)
+		return 0;
+	if (op_cpu_buffer_get_size(entry) < 2)
+		/*
+		 * the function returns 0 to indicate a too small
+		 * buffer, even if there is some space left
+		 */
+		return 0;
+	if (!op_cpu_buffer_add_data(entry, (u32)val))
+		return 0;
+	return op_cpu_buffer_add_data(entry, (u32)(val >> 32));
+}
+
+int oprofile_write_commit(struct op_entry *entry)
+{
+	if (!entry->event)
+		return -EINVAL;
+	return op_cpu_buffer_write_commit(entry);
+}
+
+void oprofile_add_pc(unsigned long pc, int is_kernel, unsigned long event)
+{
+	struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(op_cpu_buffer);
+	log_sample(cpu_buf, pc, 0, is_kernel, event, NULL);
+}
+
+void oprofile_add_trace(unsigned long pc)
+{
+	struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(op_cpu_buffer);
+
+	if (!cpu_buf->tracing)
+		return;
+
+	/*
+	 * broken frame can give an eip with the same value as an
+	 * escape code, abort the trace if we get it
+	 */
+	if (pc == ESCAPE_CODE)
+		goto fail;
+
+	if (op_add_sample(cpu_buf, pc, 0))
+		goto fail;
+
+	return;
+fail:
+	cpu_buf->tracing = 0;
+	cpu_buf->backtrace_aborted++;
+	return;
+}
+
+/*
+ * This serves to avoid cpu buffer overflow, and makes sure
+ * the task mortuary progresses
+ *
+ * By using schedule_delayed_work_on and then schedule_delayed_work
+ * we guarantee this will stay on the correct cpu
+ */
+static void wq_sync_buffer(struct work_struct *work)
+{
+	struct oprofile_cpu_buffer *b =
+		container_of(work, struct oprofile_cpu_buffer, work.work);
+	if (b->cpu != smp_processor_id()) {
+		printk(KERN_DEBUG "WQ on CPU%d, prefer CPU%d\n",
+		       smp_processor_id(), b->cpu);
+
+		if (!cpu_online(b->cpu)) {
+			cancel_delayed_work(&b->work);
+			return;
+		}
+	}
+	sync_buffer(b->cpu);
+
+	/* don't re-add the work if we're shutting down */
+	if (work_enabled)
+		schedule_delayed_work(&b->work, DEFAULT_TIMER_EXPIRE);
+}
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
new file mode 100644
index 00000000..e1d097e2
--- /dev/null
+++ b/drivers/oprofile/cpu_buffer.h
@@ -0,0 +1,121 @@
+/**
+ * @file cpu_buffer.h
+ *
+ * @remark Copyright 2002-2009 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ * @author Robert Richter <robert.richter@amd.com>
+ */
+
+#ifndef OPROFILE_CPU_BUFFER_H
+#define OPROFILE_CPU_BUFFER_H
+
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/cache.h>
+#include <linux/sched.h>
+#include <linux/ring_buffer.h>
+
+struct task_struct;
+
+int alloc_cpu_buffers(void);
+void free_cpu_buffers(void);
+
+void start_cpu_work(void);
+void end_cpu_work(void);
+void flush_cpu_work(void);
+
+/* CPU buffer is composed of such entries (which are
+ * also used for context switch notes)
+ */
+struct op_sample {
+	unsigned long eip;
+	unsigned long event;
+	unsigned long data[0];
+};
+
+struct op_entry;
+
+struct oprofile_cpu_buffer {
+	unsigned long buffer_size;
+	struct task_struct *last_task;
+	int last_is_kernel;
+	int tracing;
+	unsigned long sample_received;
+	unsigned long sample_lost_overflow;
+	unsigned long backtrace_aborted;
+	unsigned long sample_invalid_eip;
+	int cpu;
+	struct delayed_work work;
+};
+
+DECLARE_PER_CPU(struct oprofile_cpu_buffer, op_cpu_buffer);
+
+/*
+ * Resets the cpu buffer to a sane state.
+ *
+ * reset these to invalid values; the next sample collected will
+ * populate the buffer with proper values to initialize the buffer
+ */
+static inline void op_cpu_buffer_reset(int cpu)
+{
+	struct oprofile_cpu_buffer *cpu_buf = &per_cpu(op_cpu_buffer, cpu);
+
+	cpu_buf->last_is_kernel = -1;
+	cpu_buf->last_task = NULL;
+}
+
+/*
+ * op_cpu_buffer_add_data() and op_cpu_buffer_write_commit() may be
+ * called only if op_cpu_buffer_write_reserve() did not return NULL or
+ * entry->event != NULL, otherwise entry->size or entry->event will be
+ * used uninitialized.
+ */
+
+struct op_sample
+*op_cpu_buffer_write_reserve(struct op_entry *entry, unsigned long size);
+int op_cpu_buffer_write_commit(struct op_entry *entry);
+struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu);
+unsigned long op_cpu_buffer_entries(int cpu);
+
+/* returns the remaining free size of data in the entry */
+static inline
+int op_cpu_buffer_add_data(struct op_entry *entry, unsigned long val)
+{
+	if (!entry->size)
+		return 0;
+	*entry->data = val;
+	entry->size--;
+	entry->data++;
+	return entry->size;
+}
+
+/* returns the size of data in the entry */
+static inline
+int op_cpu_buffer_get_size(struct op_entry *entry)
+{
+	return entry->size;
+}
+
+/* returns 0 if empty or the size of data including the current value */
+static inline
+int op_cpu_buffer_get_data(struct op_entry *entry, unsigned long *val)
+{
+	int size = entry->size;
+	if (!size)
+		return 0;
+	*val = *entry->data;
+	entry->size--;
+	entry->data++;
+	return size;
+}
+
+/* extra data flags */
+#define KERNEL_CTX_SWITCH	(1UL << 0)
+#define IS_KERNEL		(1UL << 1)
+#define TRACE_BEGIN		(1UL << 2)
+#define USER_CTX_SWITCH		(1UL << 3)
+
+#endif /* OPROFILE_CPU_BUFFER_H */
diff --git a/drivers/oprofile/event_buffer.c b/drivers/oprofile/event_buffer.c
new file mode 100644
index 00000000..c0cc4e7f
--- /dev/null
+++ b/drivers/oprofile/event_buffer.c
@@ -0,0 +1,209 @@
+/**
+ * @file event_buffer.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ *
+ * This is the global event buffer that the user-space
+ * daemon reads from. The event buffer is an untyped array
+ * of unsigned longs. Entries are prefixed by the
+ * escape value ESCAPE_CODE followed by an identifying code.
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/oprofile.h>
+#include <linux/sched.h>
+#include <linux/capability.h>
+#include <linux/dcookies.h>
+#include <linux/fs.h>
+#include <asm/uaccess.h>
+
+#include "oprof.h"
+#include "event_buffer.h"
+#include "oprofile_stats.h"
+
+DEFINE_MUTEX(buffer_mutex);
+
+static unsigned long buffer_opened;
+static DECLARE_WAIT_QUEUE_HEAD(buffer_wait);
+static unsigned long *event_buffer;
+static unsigned long buffer_size;
+static unsigned long buffer_watershed;
+static size_t buffer_pos;
+/* atomic_t because wait_event checks it outside of buffer_mutex */
+static atomic_t buffer_ready = ATOMIC_INIT(0);
+
+/*
+ * Add an entry to the event buffer. When we get near to the end we
+ * wake up the process sleeping on the read() of the file. To protect
+ * the event_buffer this function may only be called when buffer_mutex
+ * is set.
+ */
+void add_event_entry(unsigned long value)
+{
+	/*
+	 * This shouldn't happen since all workqueues or handlers are
+	 * canceled or flushed before the event buffer is freed.
+	 */
+	if (!event_buffer) {
+		WARN_ON_ONCE(1);
+		return;
+	}
+
+	if (buffer_pos == buffer_size) {
+		atomic_inc(&oprofile_stats.event_lost_overflow);
+		return;
+	}
+
+	event_buffer[buffer_pos] = value;
+	if (++buffer_pos == buffer_size - buffer_watershed) {
+		atomic_set(&buffer_ready, 1);
+		wake_up(&buffer_wait);
+	}
+}
+
+
+/* Wake up the waiting process if any. This happens
+ * on "echo 0 >/dev/oprofile/enable" so the daemon
+ * processes the data remaining in the event buffer.
+ */
+void wake_up_buffer_waiter(void)
+{
+	mutex_lock(&buffer_mutex);
+	atomic_set(&buffer_ready, 1);
+	wake_up(&buffer_wait);
+	mutex_unlock(&buffer_mutex);
+}
+
+
+int alloc_event_buffer(void)
+{
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&oprofilefs_lock, flags);
+	buffer_size = oprofile_buffer_size;
+	buffer_watershed = oprofile_buffer_watershed;
+	raw_spin_unlock_irqrestore(&oprofilefs_lock, flags);
+
+	if (buffer_watershed >= buffer_size)
+		return -EINVAL;
+
+	buffer_pos = 0;
+	event_buffer = vmalloc(sizeof(unsigned long) * buffer_size);
+	if (!event_buffer)
+		return -ENOMEM;
+
+	return 0;
+}
+
+
+void free_event_buffer(void)
+{
+	mutex_lock(&buffer_mutex);
+	vfree(event_buffer);
+	buffer_pos = 0;
+	event_buffer = NULL;
+	mutex_unlock(&buffer_mutex);
+}
+
+
+static int event_buffer_open(struct inode *inode, struct file *file)
+{
+	int err = -EPERM;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (test_and_set_bit_lock(0, &buffer_opened))
+		return -EBUSY;
+
+	/* Register as a user of dcookies
+	 * to ensure they persist for the lifetime of
+	 * the open event file
+	 */
+	err = -EINVAL;
+	file->private_data = dcookie_register();
+	if (!file->private_data)
+		goto out;
+
+	if ((err = oprofile_setup()))
+		goto fail;
+
+	/* NB: the actual start happens from userspace
+	 * echo 1 >/dev/oprofile/enable
+	 */
+
+	return nonseekable_open(inode, file);
+
+fail:
+	dcookie_unregister(file->private_data);
+out:
+	__clear_bit_unlock(0, &buffer_opened);
+	return err;
+}
+
+
+static int event_buffer_release(struct inode *inode, struct file *file)
+{
+	oprofile_stop();
+	oprofile_shutdown();
+	dcookie_unregister(file->private_data);
+	buffer_pos = 0;
+	atomic_set(&buffer_ready, 0);
+	__clear_bit_unlock(0, &buffer_opened);
+	return 0;
+}
+
+
+static ssize_t event_buffer_read(struct file *file, char __user *buf,
+				 size_t count, loff_t *offset)
+{
+	int retval = -EINVAL;
+	size_t const max = buffer_size * sizeof(unsigned long);
+
+	/* handling partial reads is more trouble than it's worth */
+	if (count != max || *offset)
+		return -EINVAL;
+
+	wait_event_interruptible(buffer_wait, atomic_read(&buffer_ready));
+
+	if (signal_pending(current))
+		return -EINTR;
+
+	/* can't currently happen */
+	if (!atomic_read(&buffer_ready))
+		return -EAGAIN;
+
+	mutex_lock(&buffer_mutex);
+
+	/* May happen if the buffer is freed during pending reads. */
+	if (!event_buffer) {
+		retval = -EINTR;
+		goto out;
+	}
+
+	atomic_set(&buffer_ready, 0);
+
+	retval = -EFAULT;
+
+	count = buffer_pos * sizeof(unsigned long);
+
+	if (copy_to_user(buf, event_buffer, count))
+		goto out;
+
+	retval = count;
+	buffer_pos = 0;
+
+out:
+	mutex_unlock(&buffer_mutex);
+	return retval;
+}
+
+const struct file_operations event_buffer_fops = {
+	.open		= event_buffer_open,
+	.release	= event_buffer_release,
+	.read		= event_buffer_read,
+	.llseek		= no_llseek,
+};
diff --git a/drivers/oprofile/event_buffer.h b/drivers/oprofile/event_buffer.h
new file mode 100644
index 00000000..a8d5bb3c
--- /dev/null
+++ b/drivers/oprofile/event_buffer.h
@@ -0,0 +1,40 @@
+/**
+ * @file event_buffer.h
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#ifndef EVENT_BUFFER_H
+#define EVENT_BUFFER_H
+
+#include <linux/types.h>
+#include <linux/mutex.h>
+
+int alloc_event_buffer(void);
+
+void free_event_buffer(void);
+
+/**
+ * Add data to the event buffer.
+ * The data passed is free-form, but typically consists of
+ * file offsets, dcookies, context information, and ESCAPE codes.
+ */
+void add_event_entry(unsigned long data);
+
+/* wake up the process sleeping on the event file */
+void wake_up_buffer_waiter(void);
+
+#define INVALID_COOKIE ~0UL
+#define NO_COOKIE 0UL
+
+extern const struct file_operations event_buffer_fops;
+
+/* mutex between sync_cpu_buffers() and the
+ * file reading code.
+ */
+extern struct mutex buffer_mutex;
+
+#endif /* EVENT_BUFFER_H */
diff --git a/drivers/oprofile/nmi_timer_int.c b/drivers/oprofile/nmi_timer_int.c
new file mode 100644
index 00000000..76f1c935
--- /dev/null
+++ b/drivers/oprofile/nmi_timer_int.c
@@ -0,0 +1,173 @@
+/**
+ * @file nmi_timer_int.c
+ *
+ * @remark Copyright 2011 Advanced Micro Devices, Inc.
+ *
+ * @author Robert Richter <robert.richter@amd.com>
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/oprofile.h>
+#include <linux/perf_event.h>
+
+#ifdef CONFIG_OPROFILE_NMI_TIMER
+
+static DEFINE_PER_CPU(struct perf_event *, nmi_timer_events);
+static int ctr_running;
+
+static struct perf_event_attr nmi_timer_attr = {
+	.type           = PERF_TYPE_HARDWARE,
+	.config         = PERF_COUNT_HW_CPU_CYCLES,
+	.size           = sizeof(struct perf_event_attr),
+	.pinned         = 1,
+	.disabled       = 1,
+};
+
+static void nmi_timer_callback(struct perf_event *event,
+			       struct perf_sample_data *data,
+			       struct pt_regs *regs)
+{
+	event->hw.interrupts = 0;       /* don't throttle interrupts */
+	oprofile_add_sample(regs, 0);
+}
+
+static int nmi_timer_start_cpu(int cpu)
+{
+	struct perf_event *event = per_cpu(nmi_timer_events, cpu);
+
+	if (!event) {
+		event = perf_event_create_kernel_counter(&nmi_timer_attr, cpu, NULL,
+							 nmi_timer_callback, NULL);
+		if (IS_ERR(event))
+			return PTR_ERR(event);
+		per_cpu(nmi_timer_events, cpu) = event;
+	}
+
+	if (event && ctr_running)
+		perf_event_enable(event);
+
+	return 0;
+}
+
+static void nmi_timer_stop_cpu(int cpu)
+{
+	struct perf_event *event = per_cpu(nmi_timer_events, cpu);
+
+	if (event && ctr_running)
+		perf_event_disable(event);
+}
+
+static int nmi_timer_cpu_notifier(struct notifier_block *b, unsigned long action,
+				  void *data)
+{
+	int cpu = (unsigned long)data;
+	switch (action) {
+	case CPU_DOWN_FAILED:
+	case CPU_ONLINE:
+		nmi_timer_start_cpu(cpu);
+		break;
+	case CPU_DOWN_PREPARE:
+		nmi_timer_stop_cpu(cpu);
+		break;
+	}
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block nmi_timer_cpu_nb = {
+	.notifier_call = nmi_timer_cpu_notifier
+};
+
+static int nmi_timer_start(void)
+{
+	int cpu;
+
+	get_online_cpus();
+	ctr_running = 1;
+	for_each_online_cpu(cpu)
+		nmi_timer_start_cpu(cpu);
+	put_online_cpus();
+
+	return 0;
+}
+
+static void nmi_timer_stop(void)
+{
+	int cpu;
+
+	get_online_cpus();
+	for_each_online_cpu(cpu)
+		nmi_timer_stop_cpu(cpu);
+	ctr_running = 0;
+	put_online_cpus();
+}
+
+static void nmi_timer_shutdown(void)
+{
+	struct perf_event *event;
+	int cpu;
+
+	get_online_cpus();
+	unregister_cpu_notifier(&nmi_timer_cpu_nb);
+	for_each_possible_cpu(cpu) {
+		event = per_cpu(nmi_timer_events, cpu);
+		if (!event)
+			continue;
+		perf_event_disable(event);
+		per_cpu(nmi_timer_events, cpu) = NULL;
+		perf_event_release_kernel(event);
+	}
+
+	put_online_cpus();
+}
+
+static int nmi_timer_setup(void)
+{
+	int cpu, err;
+	u64 period;
+
+	/* clock cycles per tick: */
+	period = (u64)cpu_khz * 1000;
+	do_div(period, HZ);
+	nmi_timer_attr.sample_period = period;
+
+	get_online_cpus();
+	err = register_cpu_notifier(&nmi_timer_cpu_nb);
+	if (err)
+		goto out;
+	/* can't attach events to offline cpus: */
+	for_each_online_cpu(cpu) {
+		err = nmi_timer_start_cpu(cpu);
+		if (err)
+			break;
+	}
+	if (err)
+		nmi_timer_shutdown();
+out:
+	put_online_cpus();
+	return err;
+}
+
+int __init op_nmi_timer_init(struct oprofile_operations *ops)
+{
+	int err = 0;
+
+	err = nmi_timer_setup();
+	if (err)
+		return err;
+	nmi_timer_shutdown();		/* only check, don't alloc */
+
+	ops->create_files	= NULL;
+	ops->setup		= nmi_timer_setup;
+	ops->shutdown		= nmi_timer_shutdown;
+	ops->start		= nmi_timer_start;
+	ops->stop		= nmi_timer_stop;
+	ops->cpu_type		= "timer";
+
+	printk(KERN_INFO "oprofile: using NMI timer interrupt.\n");
+
+	return 0;
+}
+
+#endif
diff --git a/drivers/oprofile/oprof.c b/drivers/oprofile/oprof.c
new file mode 100644
index 00000000..fe37d854
--- /dev/null
+++ b/drivers/oprofile/oprof.c
@@ -0,0 +1,347 @@
+/**
+ * @file oprof.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/oprofile.h>
+#include <linux/moduleparam.h>
+#include <linux/workqueue.h>
+#include <linux/time.h>
+#include <linux/mutex.h>
+
+#include "oprof.h"
+#include "event_buffer.h"
+#include "cpu_buffer.h"
+#include "buffer_sync.h"
+#include "oprofile_stats.h"
+
+struct oprofile_operations oprofile_ops;
+
+unsigned long oprofile_started;
+unsigned long oprofile_backtrace_depth;
+static unsigned long is_setup;
+static DEFINE_MUTEX(start_mutex);
+
+/* timer
+   0 - use performance monitoring hardware if available
+   1 - use the timer int mechanism regardless
+ */
+static int timer = 2;
+
+/* 2013-01-14 YJChen: Add Begin */
+extern int wmt_getsyspara(char *varname, unsigned char *varval, int *varlen);
+unsigned int TIMER2_LATCH;
+/* 2013-01-14 YJChen: Add End */
+
+int oprofile_setup(void)
+{
+	int err;
+
+	mutex_lock(&start_mutex);
+
+	if ((err = alloc_cpu_buffers()))
+		goto out;
+
+	if ((err = alloc_event_buffer()))
+		goto out1;
+
+	if (oprofile_ops.setup && (err = oprofile_ops.setup()))
+		goto out2;
+
+	/* Note even though this starts part of the
+	 * profiling overhead, it's necessary to prevent
+	 * us missing task deaths and eventually oopsing
+	 * when trying to process the event buffer.
+	 */
+	if (oprofile_ops.sync_start) {
+		int sync_ret = oprofile_ops.sync_start();
+		switch (sync_ret) {
+		case 0:
+			goto post_sync;
+		case 1:
+			goto do_generic;
+		case -1:
+			goto out3;
+		default:
+			goto out3;
+		}
+	}
+do_generic:
+	if ((err = sync_start()))
+		goto out3;
+
+post_sync:
+	is_setup = 1;
+	mutex_unlock(&start_mutex);
+	return 0;
+
+out3:
+	if (oprofile_ops.shutdown)
+		oprofile_ops.shutdown();
+out2:
+	free_event_buffer();
+out1:
+	free_cpu_buffers();
+out:
+	mutex_unlock(&start_mutex);
+	return err;
+}
+
+#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
+
+static void switch_worker(struct work_struct *work);
+static DECLARE_DELAYED_WORK(switch_work, switch_worker);
+
+static void start_switch_worker(void)
+{
+	if (oprofile_ops.switch_events)
+		schedule_delayed_work(&switch_work, oprofile_time_slice);
+}
+
+static void stop_switch_worker(void)
+{
+	cancel_delayed_work_sync(&switch_work);
+}
+
+static void switch_worker(struct work_struct *work)
+{
+	if (oprofile_ops.switch_events())
+		return;
+
+	atomic_inc(&oprofile_stats.multiplex_counter);
+	start_switch_worker();
+}
+
+/* User inputs in ms, converts to jiffies */
+int oprofile_set_timeout(unsigned long val_msec)
+{
+	int err = 0;
+	unsigned long time_slice;
+
+	mutex_lock(&start_mutex);
+
+	if (oprofile_started) {
+		err = -EBUSY;
+		goto out;
+	}
+
+	if (!oprofile_ops.switch_events) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	time_slice = msecs_to_jiffies(val_msec);
+	if (time_slice == MAX_JIFFY_OFFSET) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	oprofile_time_slice = time_slice;
+
+out:
+	mutex_unlock(&start_mutex);
+	return err;
+
+}
+
+#else
+
+static inline void start_switch_worker(void) { }
+static inline void stop_switch_worker(void) { }
+
+#endif
+
+/* Actually start profiling (echo 1>/dev/oprofile/enable) */
+int oprofile_start(void)
+{
+	int err = -EINVAL;
+
+	mutex_lock(&start_mutex);
+
+	if (!is_setup)
+		goto out;
+
+	err = 0;
+
+	if (oprofile_started)
+		goto out;
+
+	oprofile_reset_stats();
+
+	if ((err = oprofile_ops.start()))
+		goto out;
+
+	start_switch_worker();
+
+	oprofile_started = 1;
+out:
+	mutex_unlock(&start_mutex);
+	return err;
+}
+
+
+/* echo 0>/dev/oprofile/enable */
+void oprofile_stop(void)
+{
+	mutex_lock(&start_mutex);
+	if (!oprofile_started)
+		goto out;
+	oprofile_ops.stop();
+	oprofile_started = 0;
+
+	stop_switch_worker();
+
+	/* wake up the daemon to read what remains */
+	wake_up_buffer_waiter();
+out:
+	mutex_unlock(&start_mutex);
+}
+
+
+void oprofile_shutdown(void)
+{
+	mutex_lock(&start_mutex);
+	if (oprofile_ops.sync_stop) {
+		int sync_ret = oprofile_ops.sync_stop();
+		switch (sync_ret) {
+		case 0:
+			goto post_sync;
+		case 1:
+			goto do_generic;
+		default:
+			goto post_sync;
+		}
+	}
+do_generic:
+	sync_stop();
+post_sync:
+	if (oprofile_ops.shutdown)
+		oprofile_ops.shutdown();
+	is_setup = 0;
+	free_event_buffer();
+	free_cpu_buffers();
+	mutex_unlock(&start_mutex);
+}
+
+int oprofile_set_ulong(unsigned long *addr, unsigned long val)
+{
+	int err = -EBUSY;
+
+	mutex_lock(&start_mutex);
+	if (!oprofile_started) {
+		*addr = val;
+		err = 0;
+	}
+	mutex_unlock(&start_mutex);
+
+	return err;
+}
+
+#if 0
+static int timer_mode;
+#endif
+
+static int __init oprofile_init(void)
+{
+	int err;
+
+/* 2013-01-14 YJChen: Add Begin */
+    char oprof_env_name[] = "wmt.oprofile.param";
+    char oprof_env_buf[32] = "0";
+    int varlen = 32;
+    int nEnable = 0;
+    int nSampleRate = 0;
+
+    if (wmt_getsyspara(oprof_env_name, oprof_env_buf, &varlen) == 0) {
+        sscanf(oprof_env_buf, "%d:%d", &nEnable, &nSampleRate);
+        printk("wmt.oprofile.param = %d:%d\n", nEnable, nSampleRate);
+        if (nEnable != 1) {
+            printk("setting disable oprofile\n");
+            return -ENODEV;
+        }
+
+        if (nSampleRate == 0) {
+            // default value is 333us
+            nSampleRate = 333;
+        }
+        else if (nSampleRate < 10) {
+            // min value is 10us
+            nSampleRate = 10;
+        }
+        printk("Enable oprofile, Sample Interval = %d usec\n", nSampleRate);
+        TIMER2_LATCH = nSampleRate * 3;
+    }
+    else {
+        // not define wmt.oprofile.param, default disable
+        printk("default disable oprofile\n");
+        return -ENODEV;
+    }
+/* 2013-01-14 YJChen: Add End */
+
+#if 0
+	/* always init architecture to setup backtrace support */
+	timer_mode = 0;
+	err = oprofile_arch_init(&oprofile_ops);
+	if (!err) {
+		if (!timer && !oprofilefs_register())
+			return 0;
+		oprofile_arch_exit();
+	}
+
+	/* setup timer mode: */
+	timer_mode = 1;
+	/* no nmi timer mode if oprofile.timer is set */
+	if (timer || op_nmi_timer_init(&oprofile_ops)) {
+		err = oprofile_timer_init(&oprofile_ops);
+		if (err)
+			return err;
+	}
+#else
+	err = oprofile_arch_init(&oprofile_ops);
+	if (err < 0 || timer) {
+        if (timer == 1) {
+            printk(KERN_INFO "oprofile: using timer interrupt.\n");
+            err = oprofile_timer_init(&oprofile_ops);
+        }
+        else if (timer == 2) {
+            printk(KERN_INFO "oprofile: using timer2 interrupt.\n");
+            err = oprofile_timer2_init(&oprofile_ops);
+        }
+        else {
+            printk(KERN_INFO "oprofile: cannot use timer[%d] interrupt.\n", timer);
+            return -ENODEV;
+        }
+		if (err)
+			return err;
+	}
+#endif
+	return oprofilefs_register();
+}
+
+
+static void __exit oprofile_exit(void)
+{
+	oprofilefs_unregister();
+#if 0
+	if (!timer_mode)
+#endif
+		oprofile_arch_exit();
+}
+
+
+module_init(oprofile_init);
+module_exit(oprofile_exit);
+
+module_param_named(timer, timer, int, 0644);
+MODULE_PARM_DESC(timer, "force use of timer interrupt");
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("John Levon <levon@movementarian.org>");
+MODULE_DESCRIPTION("OProfile system profiler");
diff --git a/drivers/oprofile/oprof.h b/drivers/oprofile/oprof.h
new file mode 100644
index 00000000..a3cafd42
--- /dev/null
+++ b/drivers/oprofile/oprof.h
@@ -0,0 +1,58 @@
+/**
+ * @file oprof.h
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#ifndef OPROF_H
+#define OPROF_H
+
+int oprofile_setup(void);
+void oprofile_shutdown(void);
+
+int oprofilefs_register(void);
+void oprofilefs_unregister(void);
+
+int oprofile_start(void);
+void oprofile_stop(void);
+
+struct oprofile_operations;
+
+extern unsigned long oprofile_buffer_size;
+extern unsigned long oprofile_cpu_buffer_size;
+extern unsigned long oprofile_buffer_watershed;
+extern unsigned long oprofile_time_slice;
+
+extern struct oprofile_operations oprofile_ops;
+extern unsigned long oprofile_started;
+extern unsigned long oprofile_backtrace_depth;
+
+/* 2013-01-14 YJChen: Add Begin */
+extern unsigned int TIMER2_LATCH;
+/* 2013-01-14 YJChen: Add End */
+
+struct super_block;
+struct dentry;
+
+void oprofile_create_files(struct super_block *sb, struct dentry *root);
+int oprofile_timer_init(struct oprofile_operations *ops);
+/* 2013-01-14 YJChen: Add Begin */
+int oprofile_timer2_init(struct oprofile_operations *ops);
+/* 2013-01-14 YJChen: Add End */
+#ifdef CONFIG_OPROFILE_NMI_TIMER
+int op_nmi_timer_init(struct oprofile_operations *ops);
+#else
+static inline int op_nmi_timer_init(struct oprofile_operations *ops)
+{
+	return -ENODEV;
+}
+#endif
+
+
+int oprofile_set_ulong(unsigned long *addr, unsigned long val);
+int oprofile_set_timeout(unsigned long time);
+
+#endif /* OPROF_H */
diff --git a/drivers/oprofile/oprofile_files.c b/drivers/oprofile/oprofile_files.c
new file mode 100644
index 00000000..84a208db
--- /dev/null
+++ b/drivers/oprofile/oprofile_files.c
@@ -0,0 +1,201 @@
+/**
+ * @file oprofile_files.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#include <linux/fs.h>
+#include <linux/oprofile.h>
+#include <linux/jiffies.h>
+
+#include "event_buffer.h"
+#include "oprofile_stats.h"
+#include "oprof.h"
+
+#define BUFFER_SIZE_DEFAULT		131072
+#define CPU_BUFFER_SIZE_DEFAULT		8192
+#define BUFFER_WATERSHED_DEFAULT	32768	/* FIXME: tune */
+#define TIME_SLICE_DEFAULT		1
+
+unsigned long oprofile_buffer_size;
+unsigned long oprofile_cpu_buffer_size;
+unsigned long oprofile_buffer_watershed;
+unsigned long oprofile_time_slice;
+
+#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
+
+static ssize_t timeout_read(struct file *file, char __user *buf,
+		size_t count, loff_t *offset)
+{
+	return oprofilefs_ulong_to_user(jiffies_to_msecs(oprofile_time_slice),
+					buf, count, offset);
+}
+
+
+static ssize_t timeout_write(struct file *file, char const __user *buf,
+		size_t count, loff_t *offset)
+{
+	unsigned long val;
+	int retval;
+
+	if (*offset)
+		return -EINVAL;
+
+	retval = oprofilefs_ulong_from_user(&val, buf, count);
+	if (retval <= 0)
+		return retval;
+
+	retval = oprofile_set_timeout(val);
+
+	if (retval)
+		return retval;
+	return count;
+}
+
+
+static const struct file_operations timeout_fops = {
+	.read		= timeout_read,
+	.write		= timeout_write,
+	.llseek		= default_llseek,
+};
+
+#endif
+
+
+static ssize_t depth_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+	return oprofilefs_ulong_to_user(oprofile_backtrace_depth, buf, count,
+					offset);
+}
+
+
+static ssize_t depth_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
+{
+	unsigned long val;
+	int retval;
+
+	if (*offset)
+		return -EINVAL;
+
+	if (!oprofile_ops.backtrace)
+		return -EINVAL;
+
+	retval = oprofilefs_ulong_from_user(&val, buf, count);
+	if (retval <= 0)
+		return retval;
+
+	retval = oprofile_set_ulong(&oprofile_backtrace_depth, val);
+	if (retval)
+		return retval;
+
+	return count;
+}
+
+
+static const struct file_operations depth_fops = {
+	.read		= depth_read,
+	.write		= depth_write,
+	.llseek		= default_llseek,
+};
+
+
+static ssize_t pointer_size_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+	return oprofilefs_ulong_to_user(sizeof(void *), buf, count, offset);
+}
+
+
+static const struct file_operations pointer_size_fops = {
+	.read		= pointer_size_read,
+	.llseek		= default_llseek,
+};
+
+
+static ssize_t cpu_type_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+	return oprofilefs_str_to_user(oprofile_ops.cpu_type, buf, count, offset);
+}
+
+
+static const struct file_operations cpu_type_fops = {
+	.read		= cpu_type_read,
+	.llseek		= default_llseek,
+};
+
+
+static ssize_t enable_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+	return oprofilefs_ulong_to_user(oprofile_started, buf, count, offset);
+}
+
+
+static ssize_t enable_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
+{
+	unsigned long val;
+	int retval;
+
+	if (*offset)
+		return -EINVAL;
+
+	retval = oprofilefs_ulong_from_user(&val, buf, count);
+	if (retval <= 0)
+		return retval;
+
+	retval = 0;
+	if (val)
+		retval = oprofile_start();
+	else
+		oprofile_stop();
+
+	if (retval)
+		return retval;
+	return count;
+}
+
+
+static const struct file_operations enable_fops = {
+	.read		= enable_read,
+	.write		= enable_write,
+	.llseek		= default_llseek,
+};
+
+
+static ssize_t dump_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
+{
+	wake_up_buffer_waiter();
+	return count;
+}
+
+
+static const struct file_operations dump_fops = {
+	.write		= dump_write,
+	.llseek		= noop_llseek,
+};
+
+void oprofile_create_files(struct super_block *sb, struct dentry *root)
+{
+	/* reinitialize default values */
+	oprofile_buffer_size =		BUFFER_SIZE_DEFAULT;
+	oprofile_cpu_buffer_size =	CPU_BUFFER_SIZE_DEFAULT;
+	oprofile_buffer_watershed =	BUFFER_WATERSHED_DEFAULT;
+	oprofile_time_slice =		msecs_to_jiffies(TIME_SLICE_DEFAULT);
+
+	oprofilefs_create_file(sb, root, "enable", &enable_fops);
+	oprofilefs_create_file_perm(sb, root, "dump", &dump_fops, 0666);
+	oprofilefs_create_file(sb, root, "buffer", &event_buffer_fops);
+	oprofilefs_create_ulong(sb, root, "buffer_size", &oprofile_buffer_size);
+	oprofilefs_create_ulong(sb, root, "buffer_watershed", &oprofile_buffer_watershed);
+	oprofilefs_create_ulong(sb, root, "cpu_buffer_size", &oprofile_cpu_buffer_size);
+	oprofilefs_create_file(sb, root, "cpu_type", &cpu_type_fops);
+	oprofilefs_create_file(sb, root, "backtrace_depth", &depth_fops);
+	oprofilefs_create_file(sb, root, "pointer_size", &pointer_size_fops);
+#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
+	oprofilefs_create_file(sb, root, "time_slice", &timeout_fops);
+#endif
+	oprofile_create_stats_files(sb, root);
+	if (oprofile_ops.create_files)
+		oprofile_ops.create_files(sb, root);
+}
diff --git a/drivers/oprofile/oprofile_perf.c b/drivers/oprofile/oprofile_perf.c
new file mode 100644
index 00000000..efc4b7f3
--- /dev/null
+++ b/drivers/oprofile/oprofile_perf.c
@@ -0,0 +1,328 @@
+/*
+ * Copyright 2010 ARM Ltd.
+ *
+ * Perf-events backend for OProfile.
+ */
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/oprofile.h>
+#include <linux/slab.h>
+
+/*
+ * Per performance monitor configuration as set via oprofilefs.
+ */
+struct op_counter_config {
+	unsigned long count;
+	unsigned long enabled;
+	unsigned long event;
+	unsigned long unit_mask;
+	unsigned long kernel;
+	unsigned long user;
+	struct perf_event_attr attr;
+};
+
+static int oprofile_perf_enabled;
+static DEFINE_MUTEX(oprofile_perf_mutex);
+
+static struct op_counter_config *counter_config;
+static struct perf_event **perf_events[NR_CPUS];
+static int num_counters;
+
+/*
+ * Overflow callback for oprofile.
+ */
+static void op_overflow_handler(struct perf_event *event,
+			struct perf_sample_data *data, struct pt_regs *regs)
+{
+	int id;
+	u32 cpu = smp_processor_id();
+
+	for (id = 0; id < num_counters; ++id)
+		if (perf_events[cpu][id] == event)
+			break;
+
+	if (id != num_counters)
+		oprofile_add_sample(regs, id);
+	else
+		pr_warning("oprofile: ignoring spurious overflow "
+				"on cpu %u\n", cpu);
+}
+
+/*
+ * Called by oprofile_perf_setup to create perf attributes to mirror the oprofile
+ * settings in counter_config. Attributes are created as `pinned' events and
+ * so are permanently scheduled on the PMU.
+ */
+static void op_perf_setup(void)
+{
+	int i;
+	u32 size = sizeof(struct perf_event_attr);
+	struct perf_event_attr *attr;
+
+	for (i = 0; i < num_counters; ++i) {
+		attr = &counter_config[i].attr;
+		memset(attr, 0, size);
+		attr->type		= PERF_TYPE_RAW;
+		attr->size		= size;
+		attr->config		= counter_config[i].event;
+		attr->sample_period	= counter_config[i].count;
+		attr->pinned		= 1;
+	}
+}
+
+static int op_create_counter(int cpu, int event)
+{
+	struct perf_event *pevent;
+
+	if (!counter_config[event].enabled || perf_events[cpu][event])
+		return 0;
+
+	pevent = perf_event_create_kernel_counter(&counter_config[event].attr,
+						  cpu, NULL,
+						  op_overflow_handler, NULL);
+
+	if (IS_ERR(pevent))
+		return PTR_ERR(pevent);
+
+	if (pevent->state != PERF_EVENT_STATE_ACTIVE) {
+		perf_event_release_kernel(pevent);
+		pr_warning("oprofile: failed to enable event %d "
+				"on CPU %d\n", event, cpu);
+		return -EBUSY;
+	}
+
+	perf_events[cpu][event] = pevent;
+
+	return 0;
+}
+
+static void op_destroy_counter(int cpu, int event)
+{
+	struct perf_event *pevent = perf_events[cpu][event];
+
+	if (pevent) {
+		perf_event_release_kernel(pevent);
+		perf_events[cpu][event] = NULL;
+	}
+}
+
+/*
+ * Called by oprofile_perf_start to create active perf events based on the
+ * perviously configured attributes.
+ */
+static int op_perf_start(void)
+{
+	int cpu, event, ret = 0;
+
+	for_each_online_cpu(cpu) {
+		for (event = 0; event < num_counters; ++event) {
+			ret = op_create_counter(cpu, event);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return ret;
+}
+
+/*
+ * Called by oprofile_perf_stop at the end of a profiling run.
+ */
+static void op_perf_stop(void)
+{
+	int cpu, event;
+
+	for_each_online_cpu(cpu)
+		for (event = 0; event < num_counters; ++event)
+			op_destroy_counter(cpu, event);
+}
+
+static int oprofile_perf_create_files(struct super_block *sb, struct dentry *root)
+{
+	unsigned int i;
+
+	for (i = 0; i < num_counters; i++) {
+		struct dentry *dir;
+		char buf[4];
+
+		snprintf(buf, sizeof buf, "%d", i);
+		dir = oprofilefs_mkdir(sb, root, buf);
+		oprofilefs_create_ulong(sb, dir, "enabled", &counter_config[i].enabled);
+		oprofilefs_create_ulong(sb, dir, "event", &counter_config[i].event);
+		oprofilefs_create_ulong(sb, dir, "count", &counter_config[i].count);
+		oprofilefs_create_ulong(sb, dir, "unit_mask", &counter_config[i].unit_mask);
+		oprofilefs_create_ulong(sb, dir, "kernel", &counter_config[i].kernel);
+		oprofilefs_create_ulong(sb, dir, "user", &counter_config[i].user);
+	}
+
+	return 0;
+}
+
+static int oprofile_perf_setup(void)
+{
+	raw_spin_lock(&oprofilefs_lock);
+	op_perf_setup();
+	raw_spin_unlock(&oprofilefs_lock);
+	return 0;
+}
+
+static int oprofile_perf_start(void)
+{
+	int ret = -EBUSY;
+
+	mutex_lock(&oprofile_perf_mutex);
+	if (!oprofile_perf_enabled) {
+		ret = 0;
+		op_perf_start();
+		oprofile_perf_enabled = 1;
+	}
+	mutex_unlock(&oprofile_perf_mutex);
+	return ret;
+}
+
+static void oprofile_perf_stop(void)
+{
+	mutex_lock(&oprofile_perf_mutex);
+	if (oprofile_perf_enabled)
+		op_perf_stop();
+	oprofile_perf_enabled = 0;
+	mutex_unlock(&oprofile_perf_mutex);
+}
+
+#ifdef CONFIG_PM
+
+static int oprofile_perf_suspend(struct platform_device *dev, pm_message_t state)
+{
+	mutex_lock(&oprofile_perf_mutex);
+	if (oprofile_perf_enabled)
+		op_perf_stop();
+	mutex_unlock(&oprofile_perf_mutex);
+	return 0;
+}
+
+static int oprofile_perf_resume(struct platform_device *dev)
+{
+	mutex_lock(&oprofile_perf_mutex);
+	if (oprofile_perf_enabled && op_perf_start())
+		oprofile_perf_enabled = 0;
+	mutex_unlock(&oprofile_perf_mutex);
+	return 0;
+}
+
+static struct platform_driver oprofile_driver = {
+	.driver		= {
+		.name		= "oprofile-perf",
+	},
+	.resume		= oprofile_perf_resume,
+	.suspend	= oprofile_perf_suspend,
+};
+
+static struct platform_device *oprofile_pdev;
+
+static int __init init_driverfs(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&oprofile_driver);
+	if (ret)
+		return ret;
+
+	oprofile_pdev =	platform_device_register_simple(
+				oprofile_driver.driver.name, 0, NULL, 0);
+	if (IS_ERR(oprofile_pdev)) {
+		ret = PTR_ERR(oprofile_pdev);
+		platform_driver_unregister(&oprofile_driver);
+	}
+
+	return ret;
+}
+
+static void exit_driverfs(void)
+{
+	platform_device_unregister(oprofile_pdev);
+	platform_driver_unregister(&oprofile_driver);
+}
+
+#else
+
+static inline int  init_driverfs(void) { return 0; }
+static inline void exit_driverfs(void) { }
+
+#endif /* CONFIG_PM */
+
+void oprofile_perf_exit(void)
+{
+	int cpu, id;
+	struct perf_event *event;
+
+	for_each_possible_cpu(cpu) {
+		for (id = 0; id < num_counters; ++id) {
+			event = perf_events[cpu][id];
+			if (event)
+				perf_event_release_kernel(event);
+		}
+
+		kfree(perf_events[cpu]);
+	}
+
+	kfree(counter_config);
+	exit_driverfs();
+}
+
+int __init oprofile_perf_init(struct oprofile_operations *ops)
+{
+	int cpu, ret = 0;
+
+	ret = init_driverfs();
+	if (ret)
+		return ret;
+
+	memset(&perf_events, 0, sizeof(perf_events));
+
+	num_counters = perf_num_counters();
+	if (num_counters <= 0) {
+		pr_info("oprofile: no performance counters\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	counter_config = kcalloc(num_counters,
+			sizeof(struct op_counter_config), GFP_KERNEL);
+
+	if (!counter_config) {
+		pr_info("oprofile: failed to allocate %d "
+				"counters\n", num_counters);
+		ret = -ENOMEM;
+		num_counters = 0;
+		goto out;
+	}
+
+	for_each_possible_cpu(cpu) {
+		perf_events[cpu] = kcalloc(num_counters,
+				sizeof(struct perf_event *), GFP_KERNEL);
+		if (!perf_events[cpu]) {
+			pr_info("oprofile: failed to allocate %d perf events "
+					"for cpu %d\n", num_counters, cpu);
+			ret = -ENOMEM;
+			goto out;
+		}
+	}
+
+	ops->create_files	= oprofile_perf_create_files;
+	ops->setup		= oprofile_perf_setup;
+	ops->start		= oprofile_perf_start;
+	ops->stop		= oprofile_perf_stop;
+	ops->shutdown		= oprofile_perf_stop;
+	ops->cpu_type		= op_name_from_perf_id();
+
+	if (!ops->cpu_type)
+		ret = -ENODEV;
+	else
+		pr_info("oprofile: using %s\n", ops->cpu_type);
+
+out:
+	if (ret)
+		oprofile_perf_exit();
+
+	return ret;
+}
diff --git a/drivers/oprofile/oprofile_stats.c b/drivers/oprofile/oprofile_stats.c
new file mode 100644
index 00000000..917d28eb
--- /dev/null
+++ b/drivers/oprofile/oprofile_stats.c
@@ -0,0 +1,84 @@
+/**
+ * @file oprofile_stats.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon
+ */
+
+#include <linux/oprofile.h>
+#include <linux/smp.h>
+#include <linux/cpumask.h>
+#include <linux/threads.h>
+
+#include "oprofile_stats.h"
+#include "cpu_buffer.h"
+
+struct oprofile_stat_struct oprofile_stats;
+
+void oprofile_reset_stats(void)
+{
+	struct oprofile_cpu_buffer *cpu_buf;
+	int i;
+
+	for_each_possible_cpu(i) {
+		cpu_buf = &per_cpu(op_cpu_buffer, i);
+		cpu_buf->sample_received = 0;
+		cpu_buf->sample_lost_overflow = 0;
+		cpu_buf->backtrace_aborted = 0;
+		cpu_buf->sample_invalid_eip = 0;
+	}
+
+	atomic_set(&oprofile_stats.sample_lost_no_mm, 0);
+	atomic_set(&oprofile_stats.sample_lost_no_mapping, 0);
+	atomic_set(&oprofile_stats.event_lost_overflow, 0);
+	atomic_set(&oprofile_stats.bt_lost_no_mapping, 0);
+	atomic_set(&oprofile_stats.multiplex_counter, 0);
+}
+
+
+void oprofile_create_stats_files(struct super_block *sb, struct dentry *root)
+{
+	struct oprofile_cpu_buffer *cpu_buf;
+	struct dentry *cpudir;
+	struct dentry *dir;
+	char buf[10];
+	int i;
+
+	dir = oprofilefs_mkdir(sb, root, "stats");
+	if (!dir)
+		return;
+
+	for_each_possible_cpu(i) {
+		cpu_buf = &per_cpu(op_cpu_buffer, i);
+		snprintf(buf, 10, "cpu%d", i);
+		cpudir = oprofilefs_mkdir(sb, dir, buf);
+
+		/* Strictly speaking access to these ulongs is racy,
+		 * but we can't simply lock them, and they are
+		 * informational only.
+		 */
+		oprofilefs_create_ro_ulong(sb, cpudir, "sample_received",
+			&cpu_buf->sample_received);
+		oprofilefs_create_ro_ulong(sb, cpudir, "sample_lost_overflow",
+			&cpu_buf->sample_lost_overflow);
+		oprofilefs_create_ro_ulong(sb, cpudir, "backtrace_aborted",
+			&cpu_buf->backtrace_aborted);
+		oprofilefs_create_ro_ulong(sb, cpudir, "sample_invalid_eip",
+			&cpu_buf->sample_invalid_eip);
+	}
+
+	oprofilefs_create_ro_atomic(sb, dir, "sample_lost_no_mm",
+		&oprofile_stats.sample_lost_no_mm);
+	oprofilefs_create_ro_atomic(sb, dir, "sample_lost_no_mapping",
+		&oprofile_stats.sample_lost_no_mapping);
+	oprofilefs_create_ro_atomic(sb, dir, "event_lost_overflow",
+		&oprofile_stats.event_lost_overflow);
+	oprofilefs_create_ro_atomic(sb, dir, "bt_lost_no_mapping",
+		&oprofile_stats.bt_lost_no_mapping);
+#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
+	oprofilefs_create_ro_atomic(sb, dir, "multiplex_counter",
+		&oprofile_stats.multiplex_counter);
+#endif
+}
diff --git a/drivers/oprofile/oprofile_stats.h b/drivers/oprofile/oprofile_stats.h
new file mode 100644
index 00000000..38b6fc02
--- /dev/null
+++ b/drivers/oprofile/oprofile_stats.h
@@ -0,0 +1,34 @@
+/**
+ * @file oprofile_stats.h
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon
+ */
+
+#ifndef OPROFILE_STATS_H
+#define OPROFILE_STATS_H
+
+#include <linux/atomic.h>
+
+struct oprofile_stat_struct {
+	atomic_t sample_lost_no_mm;
+	atomic_t sample_lost_no_mapping;
+	atomic_t bt_lost_no_mapping;
+	atomic_t event_lost_overflow;
+	atomic_t multiplex_counter;
+};
+
+extern struct oprofile_stat_struct oprofile_stats;
+
+/* reset all stats to zero */
+void oprofile_reset_stats(void);
+
+struct super_block;
+struct dentry;
+
+/* create the stats/ dir */
+void oprofile_create_stats_files(struct super_block *sb, struct dentry *root);
+
+#endif /* OPROFILE_STATS_H */
diff --git a/drivers/oprofile/oprofilefs.c b/drivers/oprofile/oprofilefs.c
new file mode 100644
index 00000000..849357c1
--- /dev/null
+++ b/drivers/oprofile/oprofilefs.c
@@ -0,0 +1,280 @@
+/**
+ * @file oprofilefs.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon
+ *
+ * A simple filesystem for configuration and
+ * access of oprofile.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/oprofile.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <asm/uaccess.h>
+
+#include "oprof.h"
+
+#define OPROFILEFS_MAGIC 0x6f70726f
+
+DEFINE_RAW_SPINLOCK(oprofilefs_lock);
+
+static struct inode *oprofilefs_get_inode(struct super_block *sb, int mode)
+{
+	struct inode *inode = new_inode(sb);
+
+	if (inode) {
+		inode->i_ino = get_next_ino();
+		inode->i_mode = mode;
+		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+	}
+	return inode;
+}
+
+
+static const struct super_operations s_ops = {
+	.statfs		= simple_statfs,
+	.drop_inode 	= generic_delete_inode,
+};
+
+
+ssize_t oprofilefs_str_to_user(char const *str, char __user *buf, size_t count, loff_t *offset)
+{
+	return simple_read_from_buffer(buf, count, offset, str, strlen(str));
+}
+
+
+#define TMPBUFSIZE 50
+
+ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user *buf, size_t count, loff_t *offset)
+{
+	char tmpbuf[TMPBUFSIZE];
+	size_t maxlen = snprintf(tmpbuf, TMPBUFSIZE, "%lu\n", val);
+	if (maxlen > TMPBUFSIZE)
+		maxlen = TMPBUFSIZE;
+	return simple_read_from_buffer(buf, count, offset, tmpbuf, maxlen);
+}
+
+
+/*
+ * Note: If oprofilefs_ulong_from_user() returns 0, then *val remains
+ * unchanged and might be uninitialized. This follows write syscall
+ * implementation when count is zero: "If count is zero ... [and if]
+ * no errors are detected, 0 will be returned without causing any
+ * other effect." (man 2 write)
+ */
+int oprofilefs_ulong_from_user(unsigned long *val, char const __user *buf, size_t count)
+{
+	char tmpbuf[TMPBUFSIZE];
+	unsigned long flags;
+
+	if (!count)
+		return 0;
+
+	if (count > TMPBUFSIZE - 1)
+		return -EINVAL;
+
+	memset(tmpbuf, 0x0, TMPBUFSIZE);
+
+	if (copy_from_user(tmpbuf, buf, count))
+		return -EFAULT;
+
+	raw_spin_lock_irqsave(&oprofilefs_lock, flags);
+	*val = simple_strtoul(tmpbuf, NULL, 0);
+	raw_spin_unlock_irqrestore(&oprofilefs_lock, flags);
+	return count;
+}
+
+
+static ssize_t ulong_read_file(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+	unsigned long *val = file->private_data;
+	return oprofilefs_ulong_to_user(*val, buf, count, offset);
+}
+
+
+static ssize_t ulong_write_file(struct file *file, char const __user *buf, size_t count, loff_t *offset)
+{
+	unsigned long value;
+	int retval;
+
+	if (*offset)
+		return -EINVAL;
+
+	retval = oprofilefs_ulong_from_user(&value, buf, count);
+	if (retval <= 0)
+		return retval;
+
+	retval = oprofile_set_ulong(file->private_data, value);
+	if (retval)
+		return retval;
+
+	return count;
+}
+
+
+static const struct file_operations ulong_fops = {
+	.read		= ulong_read_file,
+	.write		= ulong_write_file,
+	.open		= simple_open,
+	.llseek		= default_llseek,
+};
+
+
+static const struct file_operations ulong_ro_fops = {
+	.read		= ulong_read_file,
+	.open		= simple_open,
+	.llseek		= default_llseek,
+};
+
+
+static int __oprofilefs_create_file(struct super_block *sb,
+	struct dentry *root, char const *name, const struct file_operations *fops,
+	int perm, void *priv)
+{
+	struct dentry *dentry;
+	struct inode *inode;
+
+	dentry = d_alloc_name(root, name);
+	if (!dentry)
+		return -ENOMEM;
+	inode = oprofilefs_get_inode(sb, S_IFREG | perm);
+	if (!inode) {
+		dput(dentry);
+		return -ENOMEM;
+	}
+	inode->i_fop = fops;
+	d_add(dentry, inode);
+	dentry->d_inode->i_private = priv;
+	return 0;
+}
+
+
+int oprofilefs_create_ulong(struct super_block *sb, struct dentry *root,
+	char const *name, unsigned long *val)
+{
+	return __oprofilefs_create_file(sb, root, name,
+					&ulong_fops, 0644, val);
+}
+
+
+int oprofilefs_create_ro_ulong(struct super_block *sb, struct dentry *root,
+	char const *name, unsigned long *val)
+{
+	return __oprofilefs_create_file(sb, root, name,
+					&ulong_ro_fops, 0444, val);
+}
+
+
+static ssize_t atomic_read_file(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+	atomic_t *val = file->private_data;
+	return oprofilefs_ulong_to_user(atomic_read(val), buf, count, offset);
+}
+
+
+static const struct file_operations atomic_ro_fops = {
+	.read		= atomic_read_file,
+	.open		= simple_open,
+	.llseek		= default_llseek,
+};
+
+
+int oprofilefs_create_ro_atomic(struct super_block *sb, struct dentry *root,
+	char const *name, atomic_t *val)
+{
+	return __oprofilefs_create_file(sb, root, name,
+					&atomic_ro_fops, 0444, val);
+}
+
+
+int oprofilefs_create_file(struct super_block *sb, struct dentry *root,
+	char const *name, const struct file_operations *fops)
+{
+	return __oprofilefs_create_file(sb, root, name, fops, 0644, NULL);
+}
+
+
+int oprofilefs_create_file_perm(struct super_block *sb, struct dentry *root,
+	char const *name, const struct file_operations *fops, int perm)
+{
+	return __oprofilefs_create_file(sb, root, name, fops, perm, NULL);
+}
+
+
+struct dentry *oprofilefs_mkdir(struct super_block *sb,
+	struct dentry *root, char const *name)
+{
+	struct dentry *dentry;
+	struct inode *inode;
+
+	dentry = d_alloc_name(root, name);
+	if (!dentry)
+		return NULL;
+	inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
+	if (!inode) {
+		dput(dentry);
+		return NULL;
+	}
+	inode->i_op = &simple_dir_inode_operations;
+	inode->i_fop = &simple_dir_operations;
+	d_add(dentry, inode);
+	return dentry;
+}
+
+
+static int oprofilefs_fill_super(struct super_block *sb, void *data, int silent)
+{
+	struct inode *root_inode;
+
+	sb->s_blocksize = PAGE_CACHE_SIZE;
+	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+	sb->s_magic = OPROFILEFS_MAGIC;
+	sb->s_op = &s_ops;
+	sb->s_time_gran = 1;
+
+	root_inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
+	if (!root_inode)
+		return -ENOMEM;
+	root_inode->i_op = &simple_dir_inode_operations;
+	root_inode->i_fop = &simple_dir_operations;
+	sb->s_root = d_make_root(root_inode);
+	if (!sb->s_root)
+		return -ENOMEM;
+
+	oprofile_create_files(sb, sb->s_root);
+
+	// FIXME: verify kill_litter_super removes our dentries
+	return 0;
+}
+
+
+static struct dentry *oprofilefs_mount(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data)
+{
+	return mount_single(fs_type, flags, data, oprofilefs_fill_super);
+}
+
+
+static struct file_system_type oprofilefs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "oprofilefs",
+	.mount		= oprofilefs_mount,
+	.kill_sb	= kill_litter_super,
+};
+
+
+int __init oprofilefs_register(void)
+{
+	return register_filesystem(&oprofilefs_type);
+}
+
+
+void __exit oprofilefs_unregister(void)
+{
+	unregister_filesystem(&oprofilefs_type);
+}
diff --git a/drivers/oprofile/timer_int.c b/drivers/oprofile/timer_int.c
new file mode 100644
index 00000000..246c24a9
--- /dev/null
+++ b/drivers/oprofile/timer_int.c
@@ -0,0 +1,227 @@
+/**
+ * @file timer_int.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+#include <linux/smp.h>
+#include <linux/oprofile.h>
+#include <linux/profile.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/hrtimer.h>
+#include <asm/irq_regs.h>
+#include <asm/ptrace.h>
+
+/* 2013-01-14 YJChen: Add Begin */
+#include <asm/mach/irq.h>
+#include <linux/rtc.h>
+#include <mach/hardware.h>
+/* 2013-01-14 YJChen: Add End */
+
+#include "oprof.h"
+
+static DEFINE_PER_CPU(struct hrtimer, oprofile_hrtimer);
+static int ctr_running;
+
+static enum hrtimer_restart oprofile_hrtimer_notify(struct hrtimer *hrtimer)
+{
+	oprofile_add_sample(get_irq_regs(), 0);
+	hrtimer_forward_now(hrtimer, ns_to_ktime(TICK_NSEC));
+	return HRTIMER_RESTART;
+}
+
+static void __oprofile_hrtimer_start(void *unused)
+{
+	struct hrtimer *hrtimer = &__get_cpu_var(oprofile_hrtimer);
+
+	if (!ctr_running)
+		return;
+
+	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer->function = oprofile_hrtimer_notify;
+
+	hrtimer_start(hrtimer, ns_to_ktime(TICK_NSEC),
+		      HRTIMER_MODE_REL_PINNED);
+}
+
+static int oprofile_hrtimer_start(void)
+{
+	get_online_cpus();
+	ctr_running = 1;
+	on_each_cpu(__oprofile_hrtimer_start, NULL, 1);
+	put_online_cpus();
+	return 0;
+}
+
+static void __oprofile_hrtimer_stop(int cpu)
+{
+	struct hrtimer *hrtimer = &per_cpu(oprofile_hrtimer, cpu);
+
+	if (!ctr_running)
+		return;
+
+	hrtimer_cancel(hrtimer);
+}
+
+static void oprofile_hrtimer_stop(void)
+{
+	int cpu;
+
+	get_online_cpus();
+	for_each_online_cpu(cpu)
+		__oprofile_hrtimer_stop(cpu);
+	ctr_running = 0;
+	put_online_cpus();
+}
+
+static int __cpuinit oprofile_cpu_notify(struct notifier_block *self,
+					 unsigned long action, void *hcpu)
+{
+	long cpu = (long) hcpu;
+
+	switch (action) {
+	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
+		smp_call_function_single(cpu, __oprofile_hrtimer_start,
+					 NULL, 1);
+		break;
+	case CPU_DEAD:
+	case CPU_DEAD_FROZEN:
+		__oprofile_hrtimer_stop(cpu);
+		break;
+	}
+	return NOTIFY_OK;
+}
+
+static struct notifier_block __refdata oprofile_cpu_notifier = {
+	.notifier_call = oprofile_cpu_notify,
+};
+
+static int oprofile_hrtimer_setup(void)
+{
+	return register_hotcpu_notifier(&oprofile_cpu_notifier);
+}
+
+static void oprofile_hrtimer_shutdown(void)
+{
+	unregister_hotcpu_notifier(&oprofile_cpu_notifier);
+}
+
+int oprofile_timer_init(struct oprofile_operations *ops)
+{
+	ops->create_files	= NULL;
+	ops->setup		= oprofile_hrtimer_setup;
+	ops->shutdown	= oprofile_hrtimer_shutdown;
+	ops->start		= oprofile_hrtimer_start;
+	ops->stop		= oprofile_hrtimer_stop;
+	ops->cpu_type	= "timer";
+	printk(KERN_INFO "oprofile: using timer interrupt.\n");
+	return 0;
+}
+
+/* 2013-01-14 YJChen: Add Begin */
+extern unsigned int wmt_read_oscr(void);
+
+static int timer_notify(struct pt_regs *regs)
+{
+	oprofile_add_sample(regs, 0);
+	return 0;
+}
+
+static irqreturn_t
+wmt_timer2_interrupt(int irq, void *dev_id)
+{
+    unsigned int next_match;
+    int flag = 0;
+    do {
+        struct pt_regs *regs;
+
+        if (flag == 1)
+            printk(KERN_INFO "wmt_timer2_interrupt while\n");
+
+        flag = 1;
+
+        //struct pt_regs *regs = get_irq_regs(); // fix compile warning: ISO C90 forbids mixed declarations and code
+        regs = get_irq_regs();
+        timer_notify(regs);
+
+        /* Clear match on OS Timer 2 */
+        OSTS_VAL = OSTS_M2;
+        next_match = OSM2_VAL = wmt_read_oscr() + TIMER2_LATCH;
+    } while ((signed long)(next_match - wmt_read_oscr()) <= 10/*0*/);
+
+    return IRQ_HANDLED;
+}
+
+static int timer2_start(void)
+{
+    unsigned int nCount;
+    unsigned int i = 0;
+
+    /* Use OS Timer 2 as oprofile timer. */
+    i = request_irq(IRQ_OST2, wmt_timer2_interrupt, IRQF_DISABLED, "timer2", NULL);
+    if (i != 0) {
+        printk(KERN_ERR "oprofile: unable to request IRQ%u for timer2\n", IRQ_OST2);
+        return i;
+    }
+
+    nCount = wmt_read_oscr();
+    //printk(KERN_INFO "%s Enter nCount=%d\n", __FUNCTION__, nCount);
+
+    /* Set initial match */
+    while (OSTA_VAL & OSTA_MWA2)
+        ;
+
+    /* Disable match on timer 2 to cause interrupts. */
+    OSTI_VAL &= ~OSTI_E2;
+
+    OSM2_VAL = nCount + TIMER2_LATCH;
+
+    /* Enable match on timer 2 to cause interrupts. */
+    OSTI_VAL |= OSTI_E2;
+
+    /* Let OS Timer free run. */
+    if ((OSTC_VAL & OSTC_ENABLE) == 0)
+        OSTC_VAL |= OSTC_ENABLE;
+
+	return 0;
+}
+
+static void timer2_stop(void)
+{
+    /* Disable match on timer 2 to cause interrupts. */
+    OSTI_VAL &= ~OSTI_E2;
+
+    /* Set initial match */
+    while (OSTA_VAL & OSTA_MWA2)
+        ;
+
+    OSM2_VAL = 0;
+
+    free_irq(IRQ_OST2, NULL);
+}
+
+int __init oprofile_timer2_init(struct oprofile_operations *ops)
+{
+	int rc;
+
+	rc = register_hotcpu_notifier(&oprofile_cpu_notifier);
+	if (rc)
+		return rc;
+
+    ops->create_files = NULL;
+    ops->setup = oprofile_hrtimer_setup;
+    ops->shutdown = oprofile_hrtimer_shutdown;
+    ops->start = timer2_start;
+    ops->stop = timer2_stop;
+    ops->cpu_type = "timer";
+	printk(KERN_INFO "oprofile: using timer2 interrupt.\n");
+    return 0;
+}
+/* 2013-01-14 YJChen: Add End */
\ No newline at end of file