Commit 0c0a400d authored by John Levon's avatar John Levon Committed by Linus Torvalds
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[PATCH] oprofile: report anonymous region samples 



The below patch passes samples from anonymous regions to userspace instead
of just dropping them.  This provides the support needed for reporting
anonymous-region code samples (today: basic accumulated results; later:
Java and other dynamically compiled code).

As this changes the format, an upgrade to the just-released 0.9 release of
the userspace tools is required.

This patch is based upon an earlier one by Will Cohen <wcohen@redhat.com>

Signed-off-by: default avatarJohn Levon <levon@movementarian.org>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 391cd727

Documentation/Changes

+1 −1
Original line number Diff line number Diff line
@@ -63,7 +63,7 @@ o PPP 2.4.0 # pppd --version 
o  isdn4k-utils           3.1pre1                 # isdnctrl 2>&1|grep version

o  nfs-utils              1.0.5                   # showmount --version

o  procps                 3.2.0                   # ps --version

o  oprofile               0.5.3                   # oprofiled --version

o  oprofile               0.9                     # oprofiled --version



Kernel compilation

==================

Documentation/basic_profiling.txt

+7 −3
Original line number Diff line number Diff line
@@ -27,9 +27,13 @@ dump output readprofile -m /boot/System.map > captured_profile 


Oprofile

--------

Get the source (I use 0.8) from http://oprofile.sourceforge.net/

and add "idle=poll" to the kernel command line



Get the source (see Changes for required version) from

http://oprofile.sourceforge.net/ and add "idle=poll" to the kernel command

line.



Configure with CONFIG_PROFILING=y and CONFIG_OPROFILE=y & reboot on new kernel



./configure --with-kernel-support

make install
@@ -46,7 +50,7 @@ start opcontrol --start 
stop		opcontrol --stop

dump output	opreport >  output_file



To only report on the kernel, run opreport /boot/vmlinux > output_file

To only report on the kernel, run opreport -l /boot/vmlinux > output_file



A reset is needed to clear old statistics, which survive a reboot.

drivers/oprofile/buffer_sync.c

+18 −11
Original line number Diff line number Diff line
@@ -206,7 +206,7 @@ static inline unsigned long fast_get_dcookie(struct dentry * dentry, 
 */

static unsigned long get_exec_dcookie(struct mm_struct * mm)

{

	unsigned long cookie = 0;

	unsigned long cookie = NO_COOKIE;

	struct vm_area_struct * vma;

 

	if (!mm)
@@ -234,35 +234,42 @@ static unsigned long get_exec_dcookie(struct mm_struct * mm) 
 */

static unsigned long lookup_dcookie(struct mm_struct * mm, unsigned long addr, off_t * offset)

{

	unsigned long cookie = 0;

	unsigned long cookie = NO_COOKIE;

	struct vm_area_struct * vma;



	for (vma = find_vma(mm, addr); vma; vma = vma->vm_next) {

 

		if (!vma->vm_file)

			continue;



		if (addr < vma->vm_start || addr >= vma->vm_end)

			continue;



		if (vma->vm_file) {

			cookie = fast_get_dcookie(vma->vm_file->f_dentry,

				vma->vm_file->f_vfsmnt);

		*offset = (vma->vm_pgoff << PAGE_SHIFT) + addr - vma->vm_start; 

			*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 = ~0UL;

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 = ~0UL;

	last_cookie = INVALID_COOKIE;

}



static void add_kernel_ctx_switch(unsigned int in_kernel)
@@ -317,7 +324,7 @@ static int add_us_sample(struct mm_struct * mm, struct op_sample * s) 
 

 	cookie = lookup_dcookie(mm, s->eip, &offset);

 

	if (!cookie) {

	if (cookie == INVALID_COOKIE) {

		atomic_inc(&oprofile_stats.sample_lost_no_mapping);

		return 0;

	}

drivers/oprofile/event_buffer.h

+3 −0
Original line number Diff line number Diff line
@@ -35,6 +35,9 @@ void wake_up_buffer_waiter(void); 
#define TRACE_BEGIN_CODE		8

#define TRACE_END_CODE			9

 

#define INVALID_COOKIE ~0UL

#define NO_COOKIE 0UL



/* add data to the event buffer */

void add_event_entry(unsigned long data);