From fd13f6c85144bb2026c534a35be1d7cb7628a64a Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Sun, 19 Oct 2008 21:00:09 +0200
Subject: oprofile: comment cleanup

This fixes the coding style of some comments.

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 arch/x86/oprofile/op_model_amd.c | 31 ++++++++++++++++---------------
 drivers/oprofile/cpu_buffer.c    | 25 ++++++++++++++++---------
 2 files changed, 32 insertions(+), 24 deletions(-)

diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c
index 509513760a6..fb67e1999d8 100644
--- a/arch/x86/oprofile/op_model_amd.c
+++ b/arch/x86/oprofile/op_model_amd.c
@@ -65,8 +65,10 @@ static unsigned long reset_value[NUM_COUNTERS];
 #define IBS_FETCH_BEGIN 3
 #define IBS_OP_BEGIN    4
 
-/* The function interface needs to be fixed, something like add
-   data. Should then be added to linux/oprofile.h. */
+/*
+ * The function interface needs to be fixed, something like add
+ * data. Should then be added to linux/oprofile.h.
+ */
 extern void
 oprofile_add_ibs_sample(struct pt_regs *const regs,
 			unsigned int *const ibs_sample, int ibs_code);
@@ -106,7 +108,7 @@ struct ibs_op_sample {
 
 /*
  * unitialize the APIC for the IBS interrupts if needed on AMD Family10h+
-*/
+ */
 static void clear_ibs_nmi(void);
 
 static int ibs_allowed;	/* AMD Family10h and later */
@@ -223,7 +225,7 @@ op_amd_handle_ibs(struct pt_regs * const regs,
 						(unsigned int *)&ibs_fetch,
 						IBS_FETCH_BEGIN);
 
-			/*reenable the IRQ */
+			/* reenable the IRQ */
 			rdmsr(MSR_AMD64_IBSFETCHCTL, low, high);
 			high &= ~IBS_FETCH_HIGH_VALID_BIT;
 			high |= IBS_FETCH_HIGH_ENABLE;
@@ -331,8 +333,10 @@ static void op_amd_stop(struct op_msrs const * const msrs)
 	unsigned int low, high;
 	int i;
 
-	/* Subtle: stop on all counters to avoid race with
-	 * setting our pm callback */
+	/*
+	 * Subtle: stop on all counters to avoid race with setting our
+	 * pm callback
+	 */
 	for (i = 0 ; i < NUM_COUNTERS ; ++i) {
 		if (!reset_value[i])
 			continue;
@@ -343,13 +347,15 @@ static void op_amd_stop(struct op_msrs const * const msrs)
 
 #ifdef CONFIG_OPROFILE_IBS
 	if (ibs_allowed && ibs_config.fetch_enabled) {
-		low = 0;		/* clear max count and enable */
+		/* clear max count and enable */
+		low = 0;
 		high = 0;
 		wrmsr(MSR_AMD64_IBSFETCHCTL, low, high);
 	}
 
 	if (ibs_allowed && ibs_config.op_enabled) {
-		low = 0;		/* clear max count and enable */
+		/* clear max count and enable */
+		low = 0;
 		high = 0;
 		wrmsr(MSR_AMD64_IBSOPCTL, low, high);
 	}
@@ -443,10 +449,7 @@ static int pfm_amd64_setup_eilvt(void)
 	return 0;
 }
 
-/*
- * initialize the APIC for the IBS interrupts
- * if available (AMD Family10h rev B0 and later)
- */
+/* initialize the APIC for the IBS interrupts if available */
 static void setup_ibs(void)
 {
 	ibs_allowed = boot_cpu_has(X86_FEATURE_IBS);
@@ -463,9 +466,7 @@ static void setup_ibs(void)
 }
 
 
-/*
- * unitialize the APIC for the IBS interrupts if needed on AMD Family10h
- * rev B0 and later */
+/* uninitialize the APIC for the IBS interrupts if needed */
 static void clear_ibs_nmi(void)
 {
 	if (ibs_allowed)
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index 01d38e78cde..3958107723f 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -127,9 +127,10 @@ void end_cpu_work(void)
 /* Resets the cpu buffer to a sane state. */
 void cpu_buffer_reset(struct oprofile_cpu_buffer *cpu_buf)
 {
-	/* reset these to invalid values; the next sample
-	 * collected will populate the buffer with proper
-	 * values to initialize the buffer
+	/*
+	 * reset these to invalid values; the next sample collected
+	 * will populate the buffer with proper values to initialize
+	 * the buffer
 	 */
 	cpu_buf->last_is_kernel = -1;
 	cpu_buf->last_task = NULL;
@@ -151,8 +152,10 @@ static void increment_head(struct oprofile_cpu_buffer *b)
 {
 	unsigned long new_head = b->head_pos + 1;
 
-	/* Ensure anything written to the slot before we
-	 * increment is visible */
+	/*
+	 * Ensure anything written to the slot before we increment is
+	 * visible
+	 */
 	wmb();
 
 	if (new_head < b->buffer_size)
@@ -253,8 +256,10 @@ void oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
 	if (!oprofile_begin_trace(cpu_buf))
 		return;
 
-	/* if log_sample() fail we can't backtrace since we lost the source
-	 * of this event */
+	/*
+	 * if log_sample() fail we can't backtrace since we lost the
+	 * source of this event
+	 */
 	if (log_sample(cpu_buf, pc, is_kernel, event))
 		oprofile_ops.backtrace(regs, backtrace_depth);
 	oprofile_end_trace(cpu_buf);
@@ -338,8 +343,10 @@ void oprofile_add_trace(unsigned long pc)
 		return;
 	}
 
-	/* broken frame can give an eip with the same value as an escape code,
-	 * abort the trace if we get it */
+	/*
+	 * 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) {
 		cpu_buf->tracing = 0;
 		cpu_buf->backtrace_aborted++;
-- 
cgit v1.2.3


From 58494487581cb143a0d763e3056a894d5009d60a Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Wed, 26 Nov 2008 12:02:53 +0100
Subject: oprofile: update comment for oprofile_add_sample()

The cpu argument is no longer part of the parameter list.

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 include/linux/oprofile.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/include/linux/oprofile.h b/include/linux/oprofile.h
index 5231861f357..1ce9fe572e5 100644
--- a/include/linux/oprofile.h
+++ b/include/linux/oprofile.h
@@ -86,8 +86,7 @@ int oprofile_arch_init(struct oprofile_operations * ops);
 void oprofile_arch_exit(void);
 
 /**
- * Add a sample. This may be called from any context. Pass
- * smp_processor_id() as cpu.
+ * Add a sample. This may be called from any context.
  */
 void oprofile_add_sample(struct pt_regs * const regs, unsigned long event);
 
-- 
cgit v1.2.3


From cdc1834d1aa2e5b574a25e66f82625b44cdd0d8f Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Fri, 26 Sep 2008 22:18:44 -0400
Subject: oprofile: whitspace changes only

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 arch/x86/oprofile/op_model_amd.c | 4 ++--
 drivers/oprofile/cpu_buffer.c    | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c
index fb67e1999d8..f71bd218b48 100644
--- a/arch/x86/oprofile/op_model_amd.c
+++ b/arch/x86/oprofile/op_model_amd.c
@@ -70,8 +70,8 @@ static unsigned long reset_value[NUM_COUNTERS];
  * data. Should then be added to linux/oprofile.h.
  */
 extern void
-oprofile_add_ibs_sample(struct pt_regs *const regs,
-			unsigned int *const ibs_sample, int ibs_code);
+oprofile_add_ibs_sample(struct pt_regs * const regs,
+			unsigned int * const ibs_sample, int ibs_code);
 
 struct ibs_fetch_sample {
 	/* MSRC001_1031 IBS Fetch Linear Address Register */
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index 3958107723f..2c4d54187b9 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -277,8 +277,8 @@ void oprofile_add_sample(struct pt_regs * const regs, unsigned long event)
 
 #define MAX_IBS_SAMPLE_SIZE 14
 
-void oprofile_add_ibs_sample(struct pt_regs *const regs,
-			     unsigned int *const ibs_sample, int ibs_code)
+void oprofile_add_ibs_sample(struct pt_regs * const regs,
+			     unsigned int * const ibs_sample, int ibs_code)
 {
 	int is_kernel = !user_mode(regs);
 	struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(cpu_buffer);
-- 
cgit v1.2.3


From 8dbc50c322619eb821907e8dba75252f5378c712 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Wed, 26 Nov 2008 15:00:52 +0100
Subject: oprofile: fix typo

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/buffer_sync.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index b55cd23ffde..774b081b9b7 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -272,7 +272,7 @@ static void increment_tail(struct oprofile_cpu_buffer *b)
 {
 	unsigned long new_tail = b->tail_pos + 1;
 
-	rmb();	/* be sure fifo pointers are synchromized */
+	rmb();	/* be sure fifo pointers are synchronized */
 
 	if (new_tail < b->buffer_size)
 		b->tail_pos = new_tail;
-- 
cgit v1.2.3


From 9fa6812dbab9207f7af52c3d0417f1f9eb89c386 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Mon, 24 Nov 2008 14:21:03 +0100
Subject: x86/oprofile: reordering IBS code in op_model_amd.c

This is part of the cpu buffer rework.

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 arch/x86/oprofile/op_model_amd.c | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c
index f71bd218b48..8ff657b3ff8 100644
--- a/arch/x86/oprofile/op_model_amd.c
+++ b/arch/x86/oprofile/op_model_amd.c
@@ -376,18 +376,7 @@ static void op_amd_shutdown(struct op_msrs const * const msrs)
 	}
 }
 
-#ifndef CONFIG_OPROFILE_IBS
-
-/* no IBS support */
-
-static int op_amd_init(struct oprofile_operations *ops)
-{
-	return 0;
-}
-
-static void op_amd_exit(void) {}
-
-#else
+#ifdef CONFIG_OPROFILE_IBS
 
 static u8 ibs_eilvt_off;
 
@@ -531,7 +520,18 @@ static void op_amd_exit(void)
 	clear_ibs_nmi();
 }
 
-#endif
+#else
+
+/* no IBS support */
+
+static int op_amd_init(struct oprofile_operations *ops)
+{
+	return 0;
+}
+
+static void op_amd_exit(void) {}
+
+#endif /* CONFIG_OPROFILE_IBS */
 
 struct op_x86_model_spec const op_amd_spec = {
 	.init			= op_amd_init,
-- 
cgit v1.2.3


From fe615cbf34fc6a1c53c359417da4696328a488ed Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Mon, 24 Nov 2008 14:58:03 +0100
Subject: x86/oprofile: cleanup IBS init/exit functions in op_model_amd.c

Implementation of pairwise init/exit funcions for IBS and IBS NMI
setup. There are also some function renames and the removal of forward
function declarations.

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 arch/x86/oprofile/op_model_amd.c | 32 +++++++++++++++++---------------
 1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c
index 8ff657b3ff8..98658f25f54 100644
--- a/arch/x86/oprofile/op_model_amd.c
+++ b/arch/x86/oprofile/op_model_amd.c
@@ -106,11 +106,6 @@ struct ibs_op_sample {
 	unsigned int ibs_dc_phys_high;
 };
 
-/*
- * unitialize the APIC for the IBS interrupts if needed on AMD Family10h+
- */
-static void clear_ibs_nmi(void);
-
 static int ibs_allowed;	/* AMD Family10h and later */
 
 struct op_ibs_config {
@@ -390,7 +385,7 @@ static inline void apic_clear_ibs_nmi_per_cpu(void *arg)
 	setup_APIC_eilvt_ibs(0, APIC_EILVT_MSG_FIX, 1);
 }
 
-static int pfm_amd64_setup_eilvt(void)
+static int init_ibs_nmi(void)
 {
 #define IBSCTL_LVTOFFSETVAL		(1 << 8)
 #define IBSCTL				0x1cc
@@ -438,15 +433,22 @@ static int pfm_amd64_setup_eilvt(void)
 	return 0;
 }
 
+/* uninitialize the APIC for the IBS interrupts if needed */
+static void clear_ibs_nmi(void)
+{
+	if (ibs_allowed)
+		on_each_cpu(apic_clear_ibs_nmi_per_cpu, NULL, 1);
+}
+
 /* initialize the APIC for the IBS interrupts if available */
-static void setup_ibs(void)
+static void ibs_init(void)
 {
 	ibs_allowed = boot_cpu_has(X86_FEATURE_IBS);
 
 	if (!ibs_allowed)
 		return;
 
-	if (pfm_amd64_setup_eilvt()) {
+	if (init_ibs_nmi()) {
 		ibs_allowed = 0;
 		return;
 	}
@@ -454,12 +456,12 @@ static void setup_ibs(void)
 	printk(KERN_INFO "oprofile: AMD IBS detected\n");
 }
 
-
-/* uninitialize the APIC for the IBS interrupts if needed */
-static void clear_ibs_nmi(void)
+static void ibs_exit(void)
 {
-	if (ibs_allowed)
-		on_each_cpu(apic_clear_ibs_nmi_per_cpu, NULL, 1);
+	if (!ibs_allowed)
+		return;
+
+	clear_ibs_nmi();
 }
 
 static int (*create_arch_files)(struct super_block *sb, struct dentry *root);
@@ -509,7 +511,7 @@ static int setup_ibs_files(struct super_block *sb, struct dentry *root)
 
 static int op_amd_init(struct oprofile_operations *ops)
 {
-	setup_ibs();
+	ibs_init();
 	create_arch_files = ops->create_files;
 	ops->create_files = setup_ibs_files;
 	return 0;
@@ -517,7 +519,7 @@ static int op_amd_init(struct oprofile_operations *ops)
 
 static void op_amd_exit(void)
 {
-	clear_ibs_nmi();
+	ibs_exit();
 }
 
 #else
-- 
cgit v1.2.3


From fd7826d56bde11ab142d2431093773ad2b3f0a59 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Fri, 26 Sep 2008 17:50:31 -0400
Subject: oprofile: implement switch/case in buffer_sync.c

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/buffer_sync.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index 774b081b9b7..7d61ae8ee8c 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -561,6 +561,7 @@ void sync_buffer(int cpu)
 {
 	struct oprofile_cpu_buffer *cpu_buf = &per_cpu(cpu_buffer, cpu);
 	struct mm_struct *mm = NULL;
+	struct mm_struct *oldmm;
 	struct task_struct *new;
 	unsigned long cookie = 0;
 	int in_kernel = 1;
@@ -586,34 +587,39 @@ void sync_buffer(int cpu)
 		struct op_sample *s = &cpu_buf->buffer[cpu_buf->tail_pos];
 
 		if (is_code(s->eip)) {
-			if (s->event <= CPU_IS_KERNEL) {
+			switch (s->event) {
+			case 0:
+			case CPU_IS_KERNEL:
 				/* kernel/userspace switch */
 				in_kernel = s->event;
 				if (state == sb_buffer_start)
 					state = sb_sample_start;
 				add_kernel_ctx_switch(s->event);
-			} else if (s->event == CPU_TRACE_BEGIN) {
+				break;
+			case CPU_TRACE_BEGIN:
 				state = sb_bt_start;
 				add_trace_begin();
+				break;
 #ifdef CONFIG_OPROFILE_IBS
-			} else if (s->event == IBS_FETCH_BEGIN) {
+			case IBS_FETCH_BEGIN:
 				state = sb_bt_start;
 				add_ibs_begin(cpu_buf, IBS_FETCH_CODE, mm);
-			} else if (s->event == IBS_OP_BEGIN) {
+				break;
+			case IBS_OP_BEGIN:
 				state = sb_bt_start;
 				add_ibs_begin(cpu_buf, IBS_OP_CODE, mm);
+				break;
 #endif
-			} else {
-				struct mm_struct *oldmm = mm;
-
+			default:
 				/* userspace context switch */
+				oldmm = mm;
 				new = (struct task_struct *)s->event;
-
 				release_mm(oldmm);
 				mm = take_tasks_mm(new);
 				if (mm != oldmm)
 					cookie = get_exec_dcookie(mm);
 				add_user_ctx_switch(new, cookie);
+				break;
 			}
 		} else if (state >= sb_bt_start &&
 			   !add_sample(mm, s, in_kernel)) {
-- 
cgit v1.2.3


From 37ca5eb341711d7aeb9f296873b9d46eb6af33ec Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Tue, 9 Dec 2008 16:56:01 +0100
Subject: oprofile: set values to default when creating oprofilefs

This patch restores default values for:

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

when creating the oprofilefs:

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

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

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/oprofile_files.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/oprofile/oprofile_files.c b/drivers/oprofile/oprofile_files.c
index cc106d503ac..d8201998b0b 100644
--- a/drivers/oprofile/oprofile_files.c
+++ b/drivers/oprofile/oprofile_files.c
@@ -14,9 +14,13 @@
 #include "oprofile_stats.h"
 #include "oprof.h"
 
-unsigned long fs_buffer_size = 131072;
-unsigned long fs_cpu_buffer_size = 8192;
-unsigned long fs_buffer_watershed = 32768; /* FIXME: tune */
+#define FS_BUFFER_SIZE_DEFAULT		131072
+#define FS_CPU_BUFFER_SIZE_DEFAULT	8192
+#define FS_BUFFER_WATERSHED_DEFAULT	32768	/* FIXME: tune */
+
+unsigned long fs_buffer_size;
+unsigned long fs_cpu_buffer_size;
+unsigned long fs_buffer_watershed;
 
 static ssize_t depth_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
 {
@@ -120,6 +124,11 @@ static const struct file_operations dump_fops = {
 
 void oprofile_create_files(struct super_block *sb, struct dentry *root)
 {
+	/* reinitialize default values */
+	fs_buffer_size =	FS_BUFFER_SIZE_DEFAULT;
+	fs_cpu_buffer_size =	FS_CPU_BUFFER_SIZE_DEFAULT;
+	fs_buffer_watershed =	FS_BUFFER_WATERSHED_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);
-- 
cgit v1.2.3


From 68814b58c52077da9561b544089fe532a0842f71 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Mon, 24 Nov 2008 12:24:12 +0100
Subject: ring_buffer: update description for ring_buffer_alloc()

Trivial patch.

Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 kernel/trace/ring_buffer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 668bbb5ef2b..c8996d239e4 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -381,7 +381,7 @@ extern int ring_buffer_page_too_big(void);
 
 /**
  * ring_buffer_alloc - allocate a new ring_buffer
- * @size: the size in bytes that is needed.
+ * @size: the size in bytes per cpu that is needed.
  * @flags: attributes to set for the ring buffer.
  *
  * Currently the only flag that is available is the RB_FL_OVERWRITE
-- 
cgit v1.2.3


From e2ac8ef576e45d9db7264abc51383e68d26067bb Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Wed, 12 Nov 2008 12:59:32 +0100
Subject: ftrace: remove unused function arg in trace_iterator_increment()

This removes the unused cpu function parameter.

Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 kernel/trace/trace.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d86e3252f30..a96b335fe75 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -914,7 +914,7 @@ enum trace_file_type {
 	TRACE_FILE_LAT_FMT	= 1,
 };
 
-static void trace_iterator_increment(struct trace_iterator *iter, int cpu)
+static void trace_iterator_increment(struct trace_iterator *iter)
 {
 	/* Don't allow ftrace to trace into the ring buffers */
 	ftrace_disable_cpu();
@@ -993,7 +993,7 @@ static void *find_next_entry_inc(struct trace_iterator *iter)
 	iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts);
 
 	if (iter->ent)
-		trace_iterator_increment(iter, iter->cpu);
+		trace_iterator_increment(iter);
 
 	return iter->ent ? iter : NULL;
 }
-- 
cgit v1.2.3


From 7d468abee0f1a7e918b5e2f23120436a54ba9f33 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Thu, 27 Nov 2008 10:57:09 +0100
Subject: oprofile: adding cpu buffer r/w access functions

This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/buffer_sync.c | 20 +++++++++-----------
 drivers/oprofile/cpu_buffer.c  |  2 +-
 drivers/oprofile/cpu_buffer.h  | 12 ++++++++++++
 3 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index 7d61ae8ee8c..44f676c8a51 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -331,10 +331,8 @@ static void add_trace_begin(void)
 
 #define IBS_FETCH_CODE_SIZE	2
 #define IBS_OP_CODE_SIZE	5
-#define IBS_EIP(offset)				\
-	(((struct op_sample *)&cpu_buf->buffer[(offset)])->eip)
-#define IBS_EVENT(offset)				\
-	(((struct op_sample *)&cpu_buf->buffer[(offset)])->event)
+#define IBS_EIP(cpu_buf)	((cpu_buffer_read_entry(cpu_buf))->eip)
+#define IBS_EVENT(cpu_buf)	((cpu_buffer_read_entry(cpu_buf))->event)
 
 /*
  * Add IBS fetch and op entries to event buffer
@@ -349,10 +347,10 @@ static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code,
 
 	increment_tail(cpu_buf);	/* move to RIP entry */
 
-	rip = IBS_EIP(cpu_buf->tail_pos);
+	rip = IBS_EIP(cpu_buf);
 
 #ifdef __LP64__
-	rip += IBS_EVENT(cpu_buf->tail_pos) << 32;
+	rip += IBS_EVENT(cpu_buf) << 32;
 #endif
 
 	if (mm) {
@@ -376,8 +374,8 @@ static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code,
 	add_event_entry(offset);	/* Offset from Dcookie */
 
 	/* we send the Dcookie offset, but send the raw Linear Add also*/
-	add_event_entry(IBS_EIP(cpu_buf->tail_pos));
-	add_event_entry(IBS_EVENT(cpu_buf->tail_pos));
+	add_event_entry(IBS_EIP(cpu_buf));
+	add_event_entry(IBS_EVENT(cpu_buf));
 
 	if (code == IBS_FETCH_CODE)
 		count = IBS_FETCH_CODE_SIZE;	/*IBS FETCH is 2 int64s*/
@@ -386,8 +384,8 @@ static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code,
 
 	for (i = 0; i < count; i++) {
 		increment_tail(cpu_buf);
-		add_event_entry(IBS_EIP(cpu_buf->tail_pos));
-		add_event_entry(IBS_EVENT(cpu_buf->tail_pos));
+		add_event_entry(IBS_EIP(cpu_buf));
+		add_event_entry(IBS_EVENT(cpu_buf));
 	}
 }
 
@@ -584,7 +582,7 @@ void sync_buffer(int cpu)
 #else
 	while (get_slots(cpu_buf)) {
 #endif
-		struct op_sample *s = &cpu_buf->buffer[cpu_buf->tail_pos];
+		struct op_sample *s = cpu_buffer_read_entry(cpu_buf);
 
 		if (is_code(s->eip)) {
 			switch (s->event) {
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index 2c4d54187b9..7e5e650e409 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -168,7 +168,7 @@ static inline void
 add_sample(struct oprofile_cpu_buffer *cpu_buf,
 	   unsigned long pc, unsigned long event)
 {
-	struct op_sample *entry = &cpu_buf->buffer[cpu_buf->head_pos];
+	struct op_sample *entry = cpu_buffer_write_entry(cpu_buf);
 	entry->eip = pc;
 	entry->event = event;
 	increment_head(cpu_buf);
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
index d3cc26264db..08706991fdd 100644
--- a/drivers/oprofile/cpu_buffer.h
+++ b/drivers/oprofile/cpu_buffer.h
@@ -52,6 +52,18 @@ DECLARE_PER_CPU(struct oprofile_cpu_buffer, cpu_buffer);
 
 void cpu_buffer_reset(struct oprofile_cpu_buffer *cpu_buf);
 
+static inline
+struct op_sample *cpu_buffer_write_entry(struct oprofile_cpu_buffer *cpu_buf)
+{
+	return &cpu_buf->buffer[cpu_buf->head_pos];
+}
+
+static inline
+struct op_sample *cpu_buffer_read_entry(struct oprofile_cpu_buffer *cpu_buf)
+{
+	return &cpu_buf->buffer[cpu_buf->tail_pos];
+}
+
 /* transient events for the CPU buffer -> event buffer */
 #define CPU_IS_KERNEL 1
 #define CPU_TRACE_BEGIN 2
-- 
cgit v1.2.3


From 229234ae4a5ed9376b2e0524da04b0e5edadbf76 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Thu, 27 Nov 2008 18:36:08 +0100
Subject: oprofile: adding cpu_buffer_write_commit()

This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/cpu_buffer.c | 18 +-----------------
 drivers/oprofile/cpu_buffer.h | 17 +++++++++++++++++
 2 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index 7e5e650e409..d6f5de68636 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -148,22 +148,6 @@ static unsigned long nr_available_slots(struct oprofile_cpu_buffer const *b)
 	return tail + (b->buffer_size - head) - 1;
 }
 
-static void increment_head(struct oprofile_cpu_buffer *b)
-{
-	unsigned long new_head = b->head_pos + 1;
-
-	/*
-	 * Ensure anything written to the slot before we increment is
-	 * visible
-	 */
-	wmb();
-
-	if (new_head < b->buffer_size)
-		b->head_pos = new_head;
-	else
-		b->head_pos = 0;
-}
-
 static inline void
 add_sample(struct oprofile_cpu_buffer *cpu_buf,
 	   unsigned long pc, unsigned long event)
@@ -171,7 +155,7 @@ add_sample(struct oprofile_cpu_buffer *cpu_buf,
 	struct op_sample *entry = cpu_buffer_write_entry(cpu_buf);
 	entry->eip = pc;
 	entry->event = event;
-	increment_head(cpu_buf);
+	cpu_buffer_write_commit(cpu_buf);
 }
 
 static inline void
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
index 08706991fdd..e6089768ae6 100644
--- a/drivers/oprofile/cpu_buffer.h
+++ b/drivers/oprofile/cpu_buffer.h
@@ -58,6 +58,23 @@ struct op_sample *cpu_buffer_write_entry(struct oprofile_cpu_buffer *cpu_buf)
 	return &cpu_buf->buffer[cpu_buf->head_pos];
 }
 
+static inline
+void cpu_buffer_write_commit(struct oprofile_cpu_buffer *b)
+{
+	unsigned long new_head = b->head_pos + 1;
+
+	/*
+	 * Ensure anything written to the slot before we increment is
+	 * visible
+	 */
+	wmb();
+
+	if (new_head < b->buffer_size)
+		b->head_pos = new_head;
+	else
+		b->head_pos = 0;
+}
+
 static inline
 struct op_sample *cpu_buffer_read_entry(struct oprofile_cpu_buffer *cpu_buf)
 {
-- 
cgit v1.2.3


From bf589e32960181fa8cbca7bfdd92265e49dc2dfa Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Thu, 27 Nov 2008 22:33:37 +0100
Subject: oprofile: adding cpu_buffer_entries()

This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/buffer_sync.c | 31 ++-----------------------------
 drivers/oprofile/cpu_buffer.h  | 27 +++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index 44f676c8a51..aed286c3f16 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -464,33 +464,6 @@ static inline int is_code(unsigned long val)
 }
 
 
-/* "acquire" as many cpu buffer slots as we can */
-static unsigned long get_slots(struct oprofile_cpu_buffer *b)
-{
-	unsigned long head = b->head_pos;
-	unsigned long tail = b->tail_pos;
-
-	/*
-	 * Subtle. This resets the persistent last_task
-	 * and in_kernel values used for switching notes.
-	 * BUT, there is a small window between reading
-	 * head_pos, and this call, that means samples
-	 * can appear at the new head position, but not
-	 * be prefixed with the notes for switching
-	 * kernel mode or a task switch. This small hole
-	 * can lead to mis-attribution or samples where
-	 * we don't know if it's in the kernel or not,
-	 * at the start of an event buffer.
-	 */
-	cpu_buffer_reset(b);
-
-	if (head >= tail)
-		return head - tail;
-
-	return head + (b->buffer_size - tail);
-}
-
-
 /* 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,
@@ -576,11 +549,11 @@ void sync_buffer(int cpu)
 	/* Remember, only we can modify tail_pos */
 
 #ifndef CONFIG_OPROFILE_IBS
-	available = get_slots(cpu_buf);
+	available = cpu_buffer_entries(cpu_buf);
 
 	for (i = 0; i < available; ++i) {
 #else
-	while (get_slots(cpu_buf)) {
+	while (cpu_buffer_entries(cpu_buf)) {
 #endif
 		struct op_sample *s = cpu_buffer_read_entry(cpu_buf);
 
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
index e6089768ae6..6055b567839 100644
--- a/drivers/oprofile/cpu_buffer.h
+++ b/drivers/oprofile/cpu_buffer.h
@@ -81,6 +81,33 @@ struct op_sample *cpu_buffer_read_entry(struct oprofile_cpu_buffer *cpu_buf)
 	return &cpu_buf->buffer[cpu_buf->tail_pos];
 }
 
+/* "acquire" as many cpu buffer slots as we can */
+static inline
+unsigned long cpu_buffer_entries(struct oprofile_cpu_buffer *b)
+{
+	unsigned long head = b->head_pos;
+	unsigned long tail = b->tail_pos;
+
+	/*
+	 * Subtle. This resets the persistent last_task
+	 * and in_kernel values used for switching notes.
+	 * BUT, there is a small window between reading
+	 * head_pos, and this call, that means samples
+	 * can appear at the new head position, but not
+	 * be prefixed with the notes for switching
+	 * kernel mode or a task switch. This small hole
+	 * can lead to mis-attribution or samples where
+	 * we don't know if it's in the kernel or not,
+	 * at the start of an event buffer.
+	 */
+	cpu_buffer_reset(b);
+
+	if (head >= tail)
+		return head - tail;
+
+	return head + (b->buffer_size - tail);
+}
+
 /* transient events for the CPU buffer -> event buffer */
 #define CPU_IS_KERNEL 1
 #define CPU_TRACE_BEGIN 2
-- 
cgit v1.2.3


From fbc9bf9f0ed4f0fbc47dcb5b1c26c28c93b60e33 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Thu, 4 Dec 2008 16:27:00 +0100
Subject: oprofile: moving cpu_buffer_reset() to cpu_buffer.h

This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/buffer_sync.c |  1 +
 drivers/oprofile/cpu_buffer.c  | 12 ------------
 drivers/oprofile/cpu_buffer.h  | 28 +++++++++++++---------------
 3 files changed, 14 insertions(+), 27 deletions(-)

diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index aed286c3f16..944a5832d9e 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -548,6 +548,7 @@ void sync_buffer(int cpu)
 
 	/* Remember, only we can modify tail_pos */
 
+	cpu_buffer_reset(cpu);
 #ifndef CONFIG_OPROFILE_IBS
 	available = cpu_buffer_entries(cpu_buf);
 
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index d6f5de68636..5cf7efe38e6 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -124,18 +124,6 @@ void end_cpu_work(void)
 	flush_scheduled_work();
 }
 
-/* Resets the cpu buffer to a sane state. */
-void cpu_buffer_reset(struct oprofile_cpu_buffer *cpu_buf)
-{
-	/*
-	 * reset these to invalid values; the next sample collected
-	 * will populate the buffer with proper values to initialize
-	 * the buffer
-	 */
-	cpu_buf->last_is_kernel = -1;
-	cpu_buf->last_task = NULL;
-}
-
 /* compute number of available slots in cpu_buffer queue */
 static unsigned long nr_available_slots(struct oprofile_cpu_buffer const *b)
 {
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
index 6055b567839..895763f065e 100644
--- a/drivers/oprofile/cpu_buffer.h
+++ b/drivers/oprofile/cpu_buffer.h
@@ -50,7 +50,19 @@ struct oprofile_cpu_buffer {
 
 DECLARE_PER_CPU(struct oprofile_cpu_buffer, cpu_buffer);
 
-void cpu_buffer_reset(struct oprofile_cpu_buffer *cpu_buf);
+/*
+ * 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 cpu_buffer_reset(int cpu)
+{
+	struct oprofile_cpu_buffer *cpu_buf = &per_cpu(cpu_buffer, cpu);
+
+	cpu_buf->last_is_kernel = -1;
+	cpu_buf->last_task = NULL;
+}
 
 static inline
 struct op_sample *cpu_buffer_write_entry(struct oprofile_cpu_buffer *cpu_buf)
@@ -88,20 +100,6 @@ unsigned long cpu_buffer_entries(struct oprofile_cpu_buffer *b)
 	unsigned long head = b->head_pos;
 	unsigned long tail = b->tail_pos;
 
-	/*
-	 * Subtle. This resets the persistent last_task
-	 * and in_kernel values used for switching notes.
-	 * BUT, there is a small window between reading
-	 * head_pos, and this call, that means samples
-	 * can appear at the new head position, but not
-	 * be prefixed with the notes for switching
-	 * kernel mode or a task switch. This small hole
-	 * can lead to mis-attribution or samples where
-	 * we don't know if it's in the kernel or not,
-	 * at the start of an event buffer.
-	 */
-	cpu_buffer_reset(b);
-
 	if (head >= tail)
 		return head - tail;
 
-- 
cgit v1.2.3


From e09373f22e76cc048ca5fe10a9ff9012f5d64309 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Wed, 26 Nov 2008 14:04:19 +0100
Subject: ring_buffer: add remaining cpu functions to ring_buffer.h

These functions are not yet in ring_buffer.h though they seems to be
part of the API.

Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 include/linux/ring_buffer.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index e097c2e6b6d..de9d8c12e5e 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -116,6 +116,8 @@ void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu);
 
 unsigned long ring_buffer_entries(struct ring_buffer *buffer);
 unsigned long ring_buffer_overruns(struct ring_buffer *buffer);
+unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu);
+unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu);
 
 u64 ring_buffer_time_stamp(int cpu);
 void ring_buffer_normalize_time_stamp(int cpu, u64 *ts);
-- 
cgit v1.2.3


From 6dad828b76c7224a22ddc9ce7aa495d994f03b31 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Tue, 9 Dec 2008 01:21:32 +0100
Subject: oprofile: port to the new ring_buffer

This patch replaces the current oprofile cpu buffer implementation
with the ring buffer provided by the tracing framework. The motivation
here is to leave the pain of implementing ring buffers to others. Oh,
no, there are more advantages. Main reason is the support of different
sample sizes that could be stored in the buffer. Use cases for this
are IBS and Cell spu profiling. Using the new ring buffer ensures
valid and complete samples and allows copying the cpu buffer stateless
without knowing its content. Second it will use generic kernel API and
also reduce code size. And hopefully, there are less bugs.

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

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

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

Patches that changes the internal IBS buffer usage will follow.

Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/buffer_sync.c | 65 +++++++++++++++-----------------------
 drivers/oprofile/cpu_buffer.c  | 63 ++++++++++++++++++++++++++++---------
 drivers/oprofile/cpu_buffer.h  | 71 ++++++++++++++++++++++++------------------
 3 files changed, 114 insertions(+), 85 deletions(-)

diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index 944a5832d9e..737bd948482 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -268,18 +268,6 @@ lookup_dcookie(struct mm_struct *mm, unsigned long addr, off_t *offset)
 	return cookie;
 }
 
-static void increment_tail(struct oprofile_cpu_buffer *b)
-{
-	unsigned long new_tail = b->tail_pos + 1;
-
-	rmb();	/* be sure fifo pointers are synchronized */
-
-	if (new_tail < b->buffer_size)
-		b->tail_pos = new_tail;
-	else
-		b->tail_pos = 0;
-}
-
 static unsigned long last_cookie = INVALID_COOKIE;
 
 static void add_cpu_switch(int i)
@@ -331,26 +319,25 @@ static void add_trace_begin(void)
 
 #define IBS_FETCH_CODE_SIZE	2
 #define IBS_OP_CODE_SIZE	5
-#define IBS_EIP(cpu_buf)	((cpu_buffer_read_entry(cpu_buf))->eip)
-#define IBS_EVENT(cpu_buf)	((cpu_buffer_read_entry(cpu_buf))->event)
 
 /*
  * Add IBS fetch and op entries to event buffer
  */
-static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code,
-			  struct mm_struct *mm)
+static void add_ibs_begin(int cpu, int code, struct mm_struct *mm)
 {
 	unsigned long rip;
 	int i, count;
 	unsigned long ibs_cookie = 0;
 	off_t offset;
+	struct op_sample *sample;
 
-	increment_tail(cpu_buf);	/* move to RIP entry */
-
-	rip = IBS_EIP(cpu_buf);
+	sample = cpu_buffer_read_entry(cpu);
+	if (!sample)
+		goto Error;
+	rip = sample->eip;
 
 #ifdef __LP64__
-	rip += IBS_EVENT(cpu_buf) << 32;
+	rip += sample->event << 32;
 #endif
 
 	if (mm) {
@@ -374,8 +361,8 @@ static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code,
 	add_event_entry(offset);	/* Offset from Dcookie */
 
 	/* we send the Dcookie offset, but send the raw Linear Add also*/
-	add_event_entry(IBS_EIP(cpu_buf));
-	add_event_entry(IBS_EVENT(cpu_buf));
+	add_event_entry(sample->eip);
+	add_event_entry(sample->event);
 
 	if (code == IBS_FETCH_CODE)
 		count = IBS_FETCH_CODE_SIZE;	/*IBS FETCH is 2 int64s*/
@@ -383,10 +370,17 @@ static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code,
 		count = IBS_OP_CODE_SIZE;	/*IBS OP is 5 int64s*/
 
 	for (i = 0; i < count; i++) {
-		increment_tail(cpu_buf);
-		add_event_entry(IBS_EIP(cpu_buf));
-		add_event_entry(IBS_EVENT(cpu_buf));
+		sample = cpu_buffer_read_entry(cpu);
+		if (!sample)
+			goto Error;
+		add_event_entry(sample->eip);
+		add_event_entry(sample->event);
 	}
+
+	return;
+
+Error:
+	return;
 }
 
 #endif
@@ -530,33 +524,26 @@ typedef enum {
  */
 void sync_buffer(int cpu)
 {
-	struct oprofile_cpu_buffer *cpu_buf = &per_cpu(cpu_buffer, cpu);
 	struct mm_struct *mm = NULL;
 	struct mm_struct *oldmm;
 	struct task_struct *new;
 	unsigned long cookie = 0;
 	int in_kernel = 1;
 	sync_buffer_state state = sb_buffer_start;
-#ifndef CONFIG_OPROFILE_IBS
 	unsigned int i;
 	unsigned long available;
-#endif
 
 	mutex_lock(&buffer_mutex);
 
 	add_cpu_switch(cpu);
 
-	/* Remember, only we can modify tail_pos */
-
 	cpu_buffer_reset(cpu);
-#ifndef CONFIG_OPROFILE_IBS
-	available = cpu_buffer_entries(cpu_buf);
+	available = cpu_buffer_entries(cpu);
 
 	for (i = 0; i < available; ++i) {
-#else
-	while (cpu_buffer_entries(cpu_buf)) {
-#endif
-		struct op_sample *s = cpu_buffer_read_entry(cpu_buf);
+		struct op_sample *s = cpu_buffer_read_entry(cpu);
+		if (!s)
+			break;
 
 		if (is_code(s->eip)) {
 			switch (s->event) {
@@ -575,11 +562,11 @@ void sync_buffer(int cpu)
 #ifdef CONFIG_OPROFILE_IBS
 			case IBS_FETCH_BEGIN:
 				state = sb_bt_start;
-				add_ibs_begin(cpu_buf, IBS_FETCH_CODE, mm);
+				add_ibs_begin(cpu, IBS_FETCH_CODE, mm);
 				break;
 			case IBS_OP_BEGIN:
 				state = sb_bt_start;
-				add_ibs_begin(cpu_buf, IBS_OP_CODE, mm);
+				add_ibs_begin(cpu, IBS_OP_CODE, mm);
 				break;
 #endif
 			default:
@@ -600,8 +587,6 @@ void sync_buffer(int cpu)
 				atomic_inc(&oprofile_stats.bt_lost_no_mapping);
 			}
 		}
-
-		increment_tail(cpu_buf);
 	}
 	release_mm(mm);
 
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index 5cf7efe38e6..eb280ec96e2 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -28,6 +28,25 @@
 #include "buffer_sync.h"
 #include "oprof.h"
 
+#define OP_BUFFER_FLAGS	0
+
+/*
+ * Read and write access is using spin locking. Thus, writing to the
+ * buffer by NMI handler (x86) could occur also during critical
+ * sections when reading the buffer. To avoid this, there are 2
+ * buffers for independent read and write access. Read access is in
+ * process context only, write access only in the NMI handler. If the
+ * read buffer runs empty, both buffers are swapped atomically. There
+ * is potentially a small window during swapping where the buffers are
+ * disabled and samples could be lost.
+ *
+ * Using 2 buffers is a little bit overhead, but the solution is clear
+ * and does not require changes in the ring buffer implementation. It
+ * can be changed to a single buffer solution when the ring buffer
+ * access is implemented as non-locking atomic code.
+ */
+struct ring_buffer *op_ring_buffer_read;
+struct ring_buffer *op_ring_buffer_write;
 DEFINE_PER_CPU(struct oprofile_cpu_buffer, cpu_buffer);
 
 static void wq_sync_buffer(struct work_struct *work);
@@ -37,12 +56,12 @@ static int work_enabled;
 
 void free_cpu_buffers(void)
 {
-	int i;
-
-	for_each_possible_cpu(i) {
-		vfree(per_cpu(cpu_buffer, i).buffer);
-		per_cpu(cpu_buffer, i).buffer = NULL;
-	}
+	if (op_ring_buffer_read)
+		ring_buffer_free(op_ring_buffer_read);
+	op_ring_buffer_read = NULL;
+	if (op_ring_buffer_write)
+		ring_buffer_free(op_ring_buffer_write);
+	op_ring_buffer_write = NULL;
 }
 
 unsigned long oprofile_get_cpu_buffer_size(void)
@@ -64,14 +83,16 @@ int alloc_cpu_buffers(void)
 
 	unsigned long buffer_size = fs_cpu_buffer_size;
 
+	op_ring_buffer_read = ring_buffer_alloc(buffer_size, OP_BUFFER_FLAGS);
+	if (!op_ring_buffer_read)
+		goto fail;
+	op_ring_buffer_write = ring_buffer_alloc(buffer_size, OP_BUFFER_FLAGS);
+	if (!op_ring_buffer_write)
+		goto fail;
+
 	for_each_possible_cpu(i) {
 		struct oprofile_cpu_buffer *b = &per_cpu(cpu_buffer, i);
 
-		b->buffer = vmalloc_node(sizeof(struct op_sample) * buffer_size,
-			cpu_to_node(i));
-		if (!b->buffer)
-			goto fail;
-
 		b->last_task = NULL;
 		b->last_is_kernel = -1;
 		b->tracing = 0;
@@ -140,10 +161,22 @@ static inline void
 add_sample(struct oprofile_cpu_buffer *cpu_buf,
 	   unsigned long pc, unsigned long event)
 {
-	struct op_sample *entry = cpu_buffer_write_entry(cpu_buf);
-	entry->eip = pc;
-	entry->event = event;
-	cpu_buffer_write_commit(cpu_buf);
+	struct op_entry entry;
+
+	if (cpu_buffer_write_entry(&entry))
+		goto Error;
+
+	entry.sample->eip = pc;
+	entry.sample->event = event;
+
+	if (cpu_buffer_write_commit(&entry))
+		goto Error;
+
+	return;
+
+Error:
+	cpu_buf->sample_lost_overflow++;
+	return;
 }
 
 static inline void
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
index 895763f065e..aacb0f0bc56 100644
--- a/drivers/oprofile/cpu_buffer.h
+++ b/drivers/oprofile/cpu_buffer.h
@@ -15,6 +15,7 @@
 #include <linux/workqueue.h>
 #include <linux/cache.h>
 #include <linux/sched.h>
+#include <linux/ring_buffer.h>
 
 struct task_struct;
 
@@ -32,6 +33,12 @@ struct op_sample {
 	unsigned long event;
 };
 
+struct op_entry {
+	struct ring_buffer_event *event;
+	struct op_sample *sample;
+	unsigned long irq_flags;
+};
+
 struct oprofile_cpu_buffer {
 	volatile unsigned long head_pos;
 	volatile unsigned long tail_pos;
@@ -39,7 +46,6 @@ struct oprofile_cpu_buffer {
 	struct task_struct *last_task;
 	int last_is_kernel;
 	int tracing;
-	struct op_sample *buffer;
 	unsigned long sample_received;
 	unsigned long sample_lost_overflow;
 	unsigned long backtrace_aborted;
@@ -48,6 +54,8 @@ struct oprofile_cpu_buffer {
 	struct delayed_work work;
 };
 
+extern struct ring_buffer *op_ring_buffer_read;
+extern struct ring_buffer *op_ring_buffer_write;
 DECLARE_PER_CPU(struct oprofile_cpu_buffer, cpu_buffer);
 
 /*
@@ -64,46 +72,49 @@ static inline void cpu_buffer_reset(int cpu)
 	cpu_buf->last_task = NULL;
 }
 
-static inline
-struct op_sample *cpu_buffer_write_entry(struct oprofile_cpu_buffer *cpu_buf)
+static inline int cpu_buffer_write_entry(struct op_entry *entry)
 {
-	return &cpu_buf->buffer[cpu_buf->head_pos];
-}
+	entry->event = ring_buffer_lock_reserve(op_ring_buffer_write,
+						sizeof(struct op_sample),
+						&entry->irq_flags);
+	if (entry->event)
+		entry->sample = ring_buffer_event_data(entry->event);
+	else
+		entry->sample = NULL;
 
-static inline
-void cpu_buffer_write_commit(struct oprofile_cpu_buffer *b)
-{
-	unsigned long new_head = b->head_pos + 1;
+	if (!entry->sample)
+		return -ENOMEM;
 
-	/*
-	 * Ensure anything written to the slot before we increment is
-	 * visible
-	 */
-	wmb();
+	return 0;
+}
 
-	if (new_head < b->buffer_size)
-		b->head_pos = new_head;
-	else
-		b->head_pos = 0;
+static inline int cpu_buffer_write_commit(struct op_entry *entry)
+{
+	return ring_buffer_unlock_commit(op_ring_buffer_write, entry->event,
+					 entry->irq_flags);
 }
 
-static inline
-struct op_sample *cpu_buffer_read_entry(struct oprofile_cpu_buffer *cpu_buf)
+static inline struct op_sample *cpu_buffer_read_entry(int cpu)
 {
-	return &cpu_buf->buffer[cpu_buf->tail_pos];
+	struct ring_buffer_event *e;
+	e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
+	if (e)
+		return ring_buffer_event_data(e);
+	if (ring_buffer_swap_cpu(op_ring_buffer_read,
+				 op_ring_buffer_write,
+				 cpu))
+		return NULL;
+	e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
+	if (e)
+		return ring_buffer_event_data(e);
+	return NULL;
 }
 
 /* "acquire" as many cpu buffer slots as we can */
-static inline
-unsigned long cpu_buffer_entries(struct oprofile_cpu_buffer *b)
+static inline unsigned long cpu_buffer_entries(int cpu)
 {
-	unsigned long head = b->head_pos;
-	unsigned long tail = b->tail_pos;
-
-	if (head >= tail)
-		return head - tail;
-
-	return head + (b->buffer_size - tail);
+	return ring_buffer_entries_cpu(op_ring_buffer_read, cpu)
+		+ ring_buffer_entries_cpu(op_ring_buffer_write, cpu);
 }
 
 /* transient events for the CPU buffer -> event buffer */
-- 
cgit v1.2.3


From 1d7503b5dccf2b95babca050e4960e10d2633f2b Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Mon, 8 Dec 2008 11:59:52 +0100
Subject: oprofile: remove nr_available_slots()

This function is no longer available after the port to the new ring
buffer. Its removal can lead to incomplete sampling sequences since
IBS samples and backtraces are transfered in multiple samples. Due to
a full buffer, samples could be lost any time. The userspace daemon
has to live with such incomplete sampling sequences as long as the
data within one sample is consistent.

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

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/cpu_buffer.c | 34 ----------------------------------
 1 file changed, 34 deletions(-)

diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index eb280ec96e2..7f7fc958297 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -145,18 +145,6 @@ void end_cpu_work(void)
 	flush_scheduled_work();
 }
 
-/* compute number of available slots in cpu_buffer queue */
-static unsigned long nr_available_slots(struct oprofile_cpu_buffer const *b)
-{
-	unsigned long head = b->head_pos;
-	unsigned long tail = b->tail_pos;
-
-	if (tail > head)
-		return (tail - head) - 1;
-
-	return tail + (b->buffer_size - head) - 1;
-}
-
 static inline void
 add_sample(struct oprofile_cpu_buffer *cpu_buf,
 	   unsigned long pc, unsigned long event)
@@ -206,11 +194,6 @@ static int log_sample(struct oprofile_cpu_buffer *cpu_buf, unsigned long pc,
 		return 0;
 	}
 
-	if (nr_available_slots(cpu_buf) < 3) {
-		cpu_buf->sample_lost_overflow++;
-		return 0;
-	}
-
 	is_kernel = !!is_kernel;
 
 	task = current;
@@ -233,11 +216,6 @@ static int log_sample(struct oprofile_cpu_buffer *cpu_buf, unsigned long pc,
 
 static int oprofile_begin_trace(struct oprofile_cpu_buffer *cpu_buf)
 {
-	if (nr_available_slots(cpu_buf) < 4) {
-		cpu_buf->sample_lost_overflow++;
-		return 0;
-	}
-
 	add_code(cpu_buf, CPU_TRACE_BEGIN);
 	cpu_buf->tracing = 1;
 	return 1;
@@ -291,12 +269,6 @@ void oprofile_add_ibs_sample(struct pt_regs * const regs,
 
 	cpu_buf->sample_received++;
 
-	if (nr_available_slots(cpu_buf) < MAX_IBS_SAMPLE_SIZE) {
-		/* we can't backtrace since we lost the source of this event */
-		cpu_buf->sample_lost_overflow++;
-		return;
-	}
-
 	/* notice a switch from user->kernel or vice versa */
 	if (cpu_buf->last_is_kernel != is_kernel) {
 		cpu_buf->last_is_kernel = is_kernel;
@@ -342,12 +314,6 @@ void oprofile_add_trace(unsigned long pc)
 	if (!cpu_buf->tracing)
 		return;
 
-	if (nr_available_slots(cpu_buf) < 1) {
-		cpu_buf->tracing = 0;
-		cpu_buf->sample_lost_overflow++;
-		return;
-	}
-
 	/*
 	 * broken frame can give an eip with the same value as an
 	 * escape code, abort the trace if we get it
-- 
cgit v1.2.3


From 211117ff09b7d81d91b7857651587128ed8b13d9 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Tue, 9 Dec 2008 02:13:25 +0100
Subject: oprofile: fix lost sample counter

The number of lost samples could be greater than the number of
received samples. This patches fixes this. The implementation
introduces return values for add_sample() and add_code().

Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 drivers/oprofile/cpu_buffer.c | 83 +++++++++++++++++++++++++++----------------
 1 file changed, 53 insertions(+), 30 deletions(-)

diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index 7f7fc958297..61090969158 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -145,32 +145,31 @@ void end_cpu_work(void)
 	flush_scheduled_work();
 }
 
-static inline void
+static inline int
 add_sample(struct oprofile_cpu_buffer *cpu_buf,
 	   unsigned long pc, unsigned long event)
 {
 	struct op_entry entry;
+	int ret;
 
-	if (cpu_buffer_write_entry(&entry))
-		goto Error;
+	ret = cpu_buffer_write_entry(&entry);
+	if (ret)
+		return ret;
 
 	entry.sample->eip = pc;
 	entry.sample->event = event;
 
-	if (cpu_buffer_write_commit(&entry))
-		goto Error;
+	ret = cpu_buffer_write_commit(&entry);
+	if (ret)
+		return ret;
 
-	return;
-
-Error:
-	cpu_buf->sample_lost_overflow++;
-	return;
+	return 0;
 }
 
-static inline void
+static inline int
 add_code(struct oprofile_cpu_buffer *buffer, unsigned long value)
 {
-	add_sample(buffer, ESCAPE_CODE, value);
+	return add_sample(buffer, ESCAPE_CODE, value);
 }
 
 /* This must be safe from any context. It's safe writing here
@@ -201,17 +200,25 @@ static int log_sample(struct oprofile_cpu_buffer *cpu_buf, unsigned long pc,
 	/* notice a switch from user->kernel or vice versa */
 	if (cpu_buf->last_is_kernel != is_kernel) {
 		cpu_buf->last_is_kernel = is_kernel;
-		add_code(cpu_buf, is_kernel);
+		if (add_code(cpu_buf, is_kernel))
+			goto fail;
 	}
 
 	/* notice a task switch */
 	if (cpu_buf->last_task != task) {
 		cpu_buf->last_task = task;
-		add_code(cpu_buf, (unsigned long)task);
+		if (add_code(cpu_buf, (unsigned long)task))
+			goto fail;
 	}
 
-	add_sample(cpu_buf, pc, event);
+	if (add_sample(cpu_buf, pc, event))
+		goto fail;
+
 	return 1;
+
+fail:
+	cpu_buf->sample_lost_overflow++;
+	return 0;
 }
 
 static int oprofile_begin_trace(struct oprofile_cpu_buffer *cpu_buf)
@@ -266,37 +273,49 @@ void oprofile_add_ibs_sample(struct pt_regs * const regs,
 	int is_kernel = !user_mode(regs);
 	struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(cpu_buffer);
 	struct task_struct *task;
+	int fail = 0;
 
 	cpu_buf->sample_received++;
 
 	/* notice a switch from user->kernel or vice versa */
 	if (cpu_buf->last_is_kernel != is_kernel) {
+		if (add_code(cpu_buf, is_kernel))
+			goto fail;
 		cpu_buf->last_is_kernel = is_kernel;
-		add_code(cpu_buf, is_kernel);
 	}
 
 	/* notice a task switch */
 	if (!is_kernel) {
 		task = current;
 		if (cpu_buf->last_task != task) {
+			if (add_code(cpu_buf, (unsigned long)task))
+				goto fail;
 			cpu_buf->last_task = task;
-			add_code(cpu_buf, (unsigned long)task);
 		}
 	}
 
-	add_code(cpu_buf, ibs_code);
-	add_sample(cpu_buf, ibs_sample[0], ibs_sample[1]);
-	add_sample(cpu_buf, ibs_sample[2], ibs_sample[3]);
-	add_sample(cpu_buf, ibs_sample[4], ibs_sample[5]);
+	fail = fail || add_code(cpu_buf, ibs_code);
+	fail = fail || add_sample(cpu_buf, ibs_sample[0], ibs_sample[1]);
+	fail = fail || add_sample(cpu_buf, ibs_sample[2], ibs_sample[3]);
+	fail = fail || add_sample(cpu_buf, ibs_sample[4], ibs_sample[5]);
 
 	if (ibs_code == IBS_OP_BEGIN) {
-		add_sample(cpu_buf, ibs_sample[6], ibs_sample[7]);
-		add_sample(cpu_buf, ibs_sample[8], ibs_sample[9]);
-		add_sample(cpu_buf, ibs_sample[10], ibs_sample[11]);
+		fail = fail || add_sample(cpu_buf, ibs_sample[6], ibs_sample[7]);
+		fail = fail || add_sample(cpu_buf, ibs_sample[8], ibs_sample[9]);
+		fail = fail || add_sample(cpu_buf, ibs_sample[10], ibs_sample[11]);
 	}
 
+	if (fail)
+		goto fail;
+
 	if (backtrace_depth)
 		oprofile_ops.backtrace(regs, backtrace_depth);
+
+	return;
+
+fail:
+	cpu_buf->sample_lost_overflow++;
+	return;
 }
 
 #endif
@@ -318,13 +337,17 @@ void oprofile_add_trace(unsigned long pc)
 	 * 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) {
-		cpu_buf->tracing = 0;
-		cpu_buf->backtrace_aborted++;
-		return;
-	}
+	if (pc == ESCAPE_CODE)
+		goto fail;
+
+	if (add_sample(cpu_buf, pc, 0))
+		goto fail;
 
-	add_sample(cpu_buf, pc, 0);
+	return;
+fail:
+	cpu_buf->tracing = 0;
+	cpu_buf->backtrace_aborted++;
+	return;
 }
 
 /*
-- 
cgit v1.2.3


From c4f50183f90fb1fd99aa5941f01b90cd1b882d2e Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Thu, 11 Dec 2008 16:49:22 +0100
Subject: ring_buffer: adding EXPORT_SYMBOLs

I added EXPORT_SYMBOL_GPLs for all functions part of the API
(ring_buffer.h). This is required since oprofile is using the ring
buffer and the compilation as modules would fail otherwise.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/trace/ring_buffer.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index c8996d239e4..30d57dd01a8 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -31,6 +31,7 @@ void tracing_on(void)
 {
 	ring_buffers_off = 0;
 }
+EXPORT_SYMBOL_GPL(tracing_on);
 
 /**
  * tracing_off - turn off all tracing buffers
@@ -44,6 +45,7 @@ void tracing_off(void)
 {
 	ring_buffers_off = 1;
 }
+EXPORT_SYMBOL_GPL(tracing_off);
 
 /* Up this if you want to test the TIME_EXTENTS and normalization */
 #define DEBUG_SHIFT 0
@@ -60,12 +62,14 @@ u64 ring_buffer_time_stamp(int cpu)
 
 	return time;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_time_stamp);
 
 void ring_buffer_normalize_time_stamp(int cpu, u64 *ts)
 {
 	/* Just stupid testing the normalize function and deltas */
 	*ts >>= DEBUG_SHIFT;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp);
 
 #define RB_EVNT_HDR_SIZE (sizeof(struct ring_buffer_event))
 #define RB_ALIGNMENT_SHIFT	2
@@ -115,6 +119,7 @@ unsigned ring_buffer_event_length(struct ring_buffer_event *event)
 {
 	return rb_event_length(event);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_event_length);
 
 /* inline for ring buffer fast paths */
 static inline void *
@@ -136,6 +141,7 @@ void *ring_buffer_event_data(struct ring_buffer_event *event)
 {
 	return rb_event_data(event);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_event_data);
 
 #define for_each_buffer_cpu(buffer, cpu)		\
 	for_each_cpu_mask(cpu, buffer->cpumask)
@@ -444,6 +450,7 @@ struct ring_buffer *ring_buffer_alloc(unsigned long size, unsigned flags)
 	kfree(buffer);
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_alloc);
 
 /**
  * ring_buffer_free - free a ring buffer.
@@ -459,6 +466,7 @@ ring_buffer_free(struct ring_buffer *buffer)
 
 	kfree(buffer);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_free);
 
 static void rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer);
 
@@ -620,6 +628,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size)
 	mutex_unlock(&buffer->mutex);
 	return -ENOMEM;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_resize);
 
 static inline int rb_null_event(struct ring_buffer_event *event)
 {
@@ -1220,6 +1229,7 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer,
 		preempt_enable_notrace();
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_lock_reserve);
 
 static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer,
 		      struct ring_buffer_event *event)
@@ -1269,6 +1279,7 @@ int ring_buffer_unlock_commit(struct ring_buffer *buffer,
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_unlock_commit);
 
 /**
  * ring_buffer_write - write data to the buffer without reserving
@@ -1334,6 +1345,7 @@ int ring_buffer_write(struct ring_buffer *buffer,
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_write);
 
 static inline int rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer)
 {
@@ -1360,6 +1372,7 @@ void ring_buffer_record_disable(struct ring_buffer *buffer)
 {
 	atomic_inc(&buffer->record_disabled);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_record_disable);
 
 /**
  * ring_buffer_record_enable - enable writes to the buffer
@@ -1372,6 +1385,7 @@ void ring_buffer_record_enable(struct ring_buffer *buffer)
 {
 	atomic_dec(&buffer->record_disabled);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_record_enable);
 
 /**
  * ring_buffer_record_disable_cpu - stop all writes into the cpu_buffer
@@ -1393,6 +1407,7 @@ void ring_buffer_record_disable_cpu(struct ring_buffer *buffer, int cpu)
 	cpu_buffer = buffer->buffers[cpu];
 	atomic_inc(&cpu_buffer->record_disabled);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_record_disable_cpu);
 
 /**
  * ring_buffer_record_enable_cpu - enable writes to the buffer
@@ -1412,6 +1427,7 @@ void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu)
 	cpu_buffer = buffer->buffers[cpu];
 	atomic_dec(&cpu_buffer->record_disabled);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_record_enable_cpu);
 
 /**
  * ring_buffer_entries_cpu - get the number of entries in a cpu buffer
@@ -1428,6 +1444,7 @@ unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu)
 	cpu_buffer = buffer->buffers[cpu];
 	return cpu_buffer->entries;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_entries_cpu);
 
 /**
  * ring_buffer_overrun_cpu - get the number of overruns in a cpu_buffer
@@ -1444,6 +1461,7 @@ unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu)
 	cpu_buffer = buffer->buffers[cpu];
 	return cpu_buffer->overrun;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_overrun_cpu);
 
 /**
  * ring_buffer_entries - get the number of entries in a buffer
@@ -1466,6 +1484,7 @@ unsigned long ring_buffer_entries(struct ring_buffer *buffer)
 
 	return entries;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_entries);
 
 /**
  * ring_buffer_overrun_cpu - get the number of overruns in buffer
@@ -1488,6 +1507,7 @@ unsigned long ring_buffer_overruns(struct ring_buffer *buffer)
 
 	return overruns;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_overruns);
 
 /**
  * ring_buffer_iter_reset - reset an iterator
@@ -1513,6 +1533,7 @@ void ring_buffer_iter_reset(struct ring_buffer_iter *iter)
 	else
 		iter->read_stamp = iter->head_page->time_stamp;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_iter_reset);
 
 /**
  * ring_buffer_iter_empty - check if an iterator has no more to read
@@ -1527,6 +1548,7 @@ int ring_buffer_iter_empty(struct ring_buffer_iter *iter)
 	return iter->head_page == cpu_buffer->commit_page &&
 		iter->head == rb_commit_index(cpu_buffer);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_iter_empty);
 
 static void
 rb_update_read_stamp(struct ring_buffer_per_cpu *cpu_buffer,
@@ -1797,6 +1819,7 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
 
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_peek);
 
 /**
  * ring_buffer_iter_peek - peek at the next event to be read
@@ -1867,6 +1890,7 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts)
 
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_iter_peek);
 
 /**
  * ring_buffer_consume - return an event and consume it
@@ -1894,6 +1918,7 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
 
 	return event;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_consume);
 
 /**
  * ring_buffer_read_start - start a non consuming read of the buffer
@@ -1934,6 +1959,7 @@ ring_buffer_read_start(struct ring_buffer *buffer, int cpu)
 
 	return iter;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_read_start);
 
 /**
  * ring_buffer_finish - finish reading the iterator of the buffer
@@ -1950,6 +1976,7 @@ ring_buffer_read_finish(struct ring_buffer_iter *iter)
 	atomic_dec(&cpu_buffer->record_disabled);
 	kfree(iter);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_read_finish);
 
 /**
  * ring_buffer_read - read the next item in the ring buffer by the iterator
@@ -1971,6 +1998,7 @@ ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts)
 
 	return event;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_read);
 
 /**
  * ring_buffer_size - return the size of the ring buffer (in bytes)
@@ -1980,6 +2008,7 @@ unsigned long ring_buffer_size(struct ring_buffer *buffer)
 {
 	return BUF_PAGE_SIZE * buffer->pages;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_size);
 
 static void
 rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer)
@@ -2022,6 +2051,7 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu)
 
 	spin_unlock_irqrestore(&cpu_buffer->lock, flags);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_reset_cpu);
 
 /**
  * ring_buffer_reset - reset a ring buffer
@@ -2034,6 +2064,7 @@ void ring_buffer_reset(struct ring_buffer *buffer)
 	for_each_buffer_cpu(buffer, cpu)
 		ring_buffer_reset_cpu(buffer, cpu);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_reset);
 
 /**
  * rind_buffer_empty - is the ring buffer empty?
@@ -2052,6 +2083,7 @@ int ring_buffer_empty(struct ring_buffer *buffer)
 	}
 	return 1;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_empty);
 
 /**
  * ring_buffer_empty_cpu - is a cpu buffer of a ring buffer empty?
@@ -2068,6 +2100,7 @@ int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu)
 	cpu_buffer = buffer->buffers[cpu];
 	return rb_per_cpu_empty(cpu_buffer);
 }
+EXPORT_SYMBOL_GPL(ring_buffer_empty_cpu);
 
 /**
  * ring_buffer_swap_cpu - swap a CPU buffer between two ring buffers
@@ -2117,6 +2150,7 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu);
 
 static ssize_t
 rb_simple_read(struct file *filp, char __user *ubuf,
-- 
cgit v1.2.3


From d69d59f49763e6bd047c591c6c1f84c8e13da931 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 12 Dec 2008 09:38:57 +0100
Subject: oprofile: select RING_BUFFER

Impact: build fix

OProfile now depends on the ring buffer infrastructure:

 arch/x86/oprofile/built-in.o: In function `oprofile_add_ibs_sample':
 : undefined reference to `ring_buffer_unlock_commit'

Select TRACING and RING_BUFFER when oprofile is enabled.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/Kconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/Kconfig b/arch/Kconfig
index 471e72dbaf8..2e13aa26192 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -6,6 +6,8 @@ config OPROFILE
 	tristate "OProfile system profiling (EXPERIMENTAL)"
 	depends on PROFILING
 	depends on HAVE_OPROFILE
+	select TRACING
+	select RING_BUFFER
 	help
 	  OProfile is a profiling system capable of profiling the
 	  whole system, include the kernel, kernel modules, libraries,
-- 
cgit v1.2.3