Iotrace improvements

PATCH Superseded Ramon Fried 2 participants 9 messages May 28, 2018 – May 30, 2018

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Ramon Fried

author

2018-05-28 11:03 UTC #0 lore raw

v3 cover Iotrace improvements

These set of patches add few improvements to iotrace.
* Region limiting - allows setting an address and size where only
io operations that falls into that address are logged.
* Timestamping - Timestamp every iotrace record with current timestamp
* dumping - iotrace dump command for dumping all records from buffer
in a readable fashion.

In terms of backwards compatibility, the timestamp is not backward compatible as it changes the iotrace record. so if one developed an offline parsing tool it will be broken.
I though of adding #ifdef specific for that, but eventually I didn't.

v2:
* fixed printf format
* added a fix when the buffer is full
v3:
* changed the "buffer full" scenario as
recommended by Simon Glass.
This fix is dependand on a sperate patch that introduces WARN_ONCE definition in bug.h (https://patchwork.ozlabs.org/patch/921391/)

Ramon Fried (6):
cmd: iotrace: add set region command
iotrace: add IO region limit
common: iotrace: add timestamp to iotrace records
iotrace: move record definitons to header file
cmd: iotrace: add dump trace command
iotrace: fix behaviour when buffer is full

 cmd/iotrace.c     | 63 ++++++++++++++++++++++++++++++++++++++++++---
 common/iotrace.c  | 65 +++++++++++++++++++++++++++--------------------
 include/iotrace.h | 57 +++++++++++++++++++++++++++++++++++++++--
 3 files changed, 153 insertions(+), 32 deletions(-)

Signature · 2 lines

The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Ramon Fried

author

2018-05-28 11:03 UTC #1 lore raw

PATCH v3 1/6 cmd: iotrace: add set region command

Signed-off-by Ramon Fried <[email protected]>

Reviewed-by Simon Glass <[email protected]>

---
 cmd/iotrace.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

cmd/iotrace.c +22 -0

index e496787e0d0..601b8c8e32a 100644
@@ -15,6 +15,9 @@ static void do_print_stats(void)
 	iotrace_get_buffer(&start, &size, &offset, &count);
 	printf("Start:  %08lx\n", start);
 	printf("Size:   %08lx\n", size);
+	iotrace_get_region(&start, &size);
+	printf("Region: %08lx\n", start);
+	printf("Size:   %08lx\n", size);
 	printf("Offset: %08lx\n", offset);
 	printf("Output: %08lx\n", start + offset);
 	printf("Count:  %08lx\n", count);

@@ -37,6 +40,22 @@ static int do_set_buffer(int argc, char * const argv[])
 	return 0;
 }
 
+static int do_set_region(int argc, char * const argv[])
+{
+	ulong addr = 0, size = 0;
+
+	if (argc == 2) {
+		addr = simple_strtoul(*argv++, NULL, 16);
+		size = simple_strtoul(*argv++, NULL, 16);
+	} else if (argc != 0) {
+		return CMD_RET_USAGE;
+	}
+
+	iotrace_set_region(addr, size);
+
+	return 0;
+}
+
 int do_iotrace(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	const char *cmd = argc < 2 ? NULL : argv[1];

@@ -46,6 +65,8 @@ int do_iotrace(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	switch (*cmd) {
 	case 'b':
 		return do_set_buffer(argc - 2, argv + 2);
+	case 'l':
+		return do_set_region(argc - 2, argv + 2);
 	case 'p':
 		iotrace_set_enabled(0);
 		break;

@@ -67,6 +88,7 @@ U_BOOT_CMD(
 	"iotrace utility commands",
 	"stats                        - display iotrace stats\n"
 	"iotrace buffer <address> <size>      - set iotrace buffer\n"
+	"iotrace limit <address> <size>       - set iotrace region limit\n"
 	"iotrace pause                        - pause tracing\n"
 	"iotrace resume                       - resume tracing"
 );

Signature · 2 lines

The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Ramon Fried

author

2018-05-28 11:03 UTC #2 lore raw

PATCH v3 2/6 iotrace: add IO region limit

In reply to Ramon Fried

When dealing with a lot of IO regions, sometimes
it makes sense only to trace a specific one.
This patch adds support for region limits.
If region is not set, the iotrace works the same as it was. If region is set, the iotrace only logs io operation that falls in the defined region.

Signed-off-by Ramon Fried <[email protected]>

Reviewed-by Simon Glass <[email protected]>

---
 common/iotrace.c  | 27 +++++++++++++++++++++++++++
 include/iotrace.h | 24 ++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

common/iotrace.c +27 -0

index b16b0d612dd..f39885663a3 100644
@@ -42,6 +42,8 @@ struct iotrace_record {
  * @start:	Start address of iotrace buffer
  * @size:	Size of iotrace buffer in bytes
  * @offset:	Current write offset into iotrace buffer
+ * @region_start: Address of IO region to trace
+ * @region_size: Size of region to trace. if 0 will trace all address space
  * @crc32:	Current value of CRC chceksum of trace records
  * @enabled:	true if enabled, false if disabled
  */

@@ -49,6 +51,8 @@ static struct iotrace {
 	ulong start;
 	ulong size;
 	ulong offset;
+	ulong region_start;
+	ulong region_size;
 	u32 crc32;
 	bool enabled;
 } iotrace;

@@ -66,6 +70,11 @@ static void add_record(int flags, const void *ptr, ulong value)
 	if (!(gd->flags & GD_FLG_RELOC) || !iotrace.enabled)
 		return;
 
+	if (iotrace.region_size)
+		if ((ulong)ptr < iotrace.region_start ||
+		    (ulong)ptr > iotrace.region_start + iotrace.region_size)
+			return;
+
 	/* Store it if there is room */
 	if (iotrace.offset + sizeof(*rec) < iotrace.size) {
 		rec = (struct iotrace_record *)map_sysmem(

@@ -142,6 +151,24 @@ u32 iotrace_get_checksum(void)
 	return iotrace.crc32;
 }
 
+void iotrace_set_region(ulong start, ulong size)
+{
+	iotrace.region_start = start;
+	iotrace.region_size = size;
+}
+
+void iotrace_reset_region(void)
+{
+	iotrace.region_start = 0;
+	iotrace.region_size = 0;
+}
+
+void iotrace_get_region(ulong *start, ulong *size)
+{
+	*start = iotrace.region_start;
+	*size = iotrace.region_size;
+}
+
 void iotrace_set_enabled(int enable)
 {
 	iotrace.enabled = enable;

include/iotrace.h +24 -0

index 9fe5733f877..1efb117343a 100644
@@ -58,6 +58,30 @@ void iotrace_reset_checksum(void);
  */
 u32 iotrace_get_checksum(void);
 
+/**
+ * iotrace_set_region() - Set whether iotrace is limited to a specific
+ * io region.
+ *
+ * Defines the address and size of the limited region.
+ *
+ * @start: address of the beginning of the region
+ * @size: size of the region in bytes.
+ */
+void iotrace_set_region(ulong start, ulong size);
+
+/**
+ * iotrace_reset_region() - Reset the region limit
+ */
+void iotrace_reset_region(void);
+
+/**
+ * iotrace_get_region() - Get region information
+ *
+ * @start: Returns start address of region
+ * @size: Returns size of region in bytes
+ */
+void iotrace_get_region(ulong *start, ulong *size);
+
 /**
  * iotrace_set_enabled() - Set whether iotracing is enabled or not
  *

Signature · 2 lines

The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Ramon Fried

author

2018-05-28 11:03 UTC #3 lore raw

PATCH v3 3/6 common: iotrace: add timestamp to iotrace records

In reply to Ramon Fried

Add timestamp to each iotrace record to aid in debugging of IO timing access bugs.

Signed-off-by Ramon Fried <[email protected]>

Reviewed-by Simon Glass <[email protected]>

---
 common/iotrace.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

common/iotrace.c +3 -1

index f39885663a3..2f03a6082e8 100644
@@ -27,11 +27,13 @@ enum iotrace_flags {
  * struct iotrace_record - Holds a single I/O trace record
  *
  * @flags: I/O access type
+ * @timestamp: Timestamp of access
  * @addr: Address of access
  * @value: Value written or read
  */
 struct iotrace_record {
 	enum iotrace_flags flags;
+	u64 timestamp;
 	phys_addr_t addr;
 	iovalue_t value;
 };

@@ -81,7 +83,7 @@ static void add_record(int flags, const void *ptr, ulong value)
 					iotrace.start + iotrace.offset,
 					sizeof(value));
 	}
-
+	rec->timestamp = timer_get_us();
 	rec->flags = flags;
 	rec->addr = map_to_sysmem(ptr);
 	rec->value = value;

Signature · 2 lines

The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Ramon Fried

author

2018-05-28 11:03 UTC #4 lore raw

PATCH v3 4/6 iotrace: move record definitons to header file

In reply to Ramon Fried

The header definitions are needed for reading
record information in cmd/iotrace.c

Signed-off-by Ramon Fried <[email protected]>

Reviewed-by Simon Glass <[email protected]>

---
 common/iotrace.c  | 27 ---------------------------
 include/iotrace.h | 28 ++++++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 27 deletions(-)

common/iotrace.c +0 ~~-27~~

index 2f03a6082e8..83691b1dba9 100644
@@ -11,33 +11,6 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-/* Support up to the machine word length for now */
-typedef ulong iovalue_t;
-
-enum iotrace_flags {
-	IOT_8 = 0,
-	IOT_16,
-	IOT_32,
-
-	IOT_READ = 0 << 3,
-	IOT_WRITE = 1 << 3,
-};
-
-/**
- * struct iotrace_record - Holds a single I/O trace record
- *
- * @flags: I/O access type
- * @timestamp: Timestamp of access
- * @addr: Address of access
- * @value: Value written or read
- */
-struct iotrace_record {
-	enum iotrace_flags flags;
-	u64 timestamp;
-	phys_addr_t addr;
-	iovalue_t value;
-};
-
 /**
  * struct iotrace - current trace status and checksum
  *

include/iotrace.h +28 -0

index 1efb117343a..b6e006ced06 100644
@@ -7,6 +7,34 @@
 #define __IOTRACE_H
 
 #include <linux/types.h>
+#include <common.h>
+
+/* Support up to the machine word length for now */
+typedef ulong iovalue_t;
+
+enum iotrace_flags {
+	IOT_8 = 0,
+	IOT_16,
+	IOT_32,
+
+	IOT_READ = 0 << 3,
+	IOT_WRITE = 1 << 3,
+};
+
+/**
+ * struct iotrace_record - Holds a single I/O trace record
+ *
+ * @flags: I/O access type
+ * @timestamp: Timestamp of access
+ * @addr: Address of access
+ * @value: Value written or read
+ */
+struct iotrace_record {
+	enum iotrace_flags flags;
+	u64 timestamp;
+	phys_addr_t addr;
+	iovalue_t value;
+};
 
 /*
  * This file is designed to be included in arch/<arch>/include/asm/io.h.

Signature · 2 lines

The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Ramon Fried

author

2018-05-28 11:03 UTC #5 lore raw

PATCH v2 5/6 cmd: iotrace: add dump trace command

In reply to Ramon Fried

Add dump trace command which dump all trace
buffer content in a much more readable fashion
than md.

Signed-off-by Ramon Fried <[email protected]>

Reviewed-by Simon Glass <[email protected]>

---
 cmd/iotrace.c | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

cmd/iotrace.c +35 -1

index 601b8c8e32a..f50a3c3a1a9 100644
@@ -24,6 +24,36 @@ static void do_print_stats(void)
 	printf("CRC32:  %08lx\n", (ulong)iotrace_get_checksum());
 }
 
+static void do_print_trace(void)
+{
+	ulong start, size, offset, count;
+
+	struct iotrace_record *cur_record;
+
+	iotrace_get_buffer(&start, &size, &offset, &count);
+
+	if (!start || !size || !count)
+		return;
+
+	printf("Timestamp  Value          Address\n");
+
+	cur_record = (struct iotrace_record *)start;
+	for (int i = 0; i < count; i++) {
+		if (cur_record->flags & IOT_WRITE)
+			printf("%08llu: 0x%08lx --> 0x%08lx\n",
+			       cur_record->timestamp,
+					cur_record->value,
+					cur_record->addr);
+		else
+			printf("%08llu: 0x%08lx <-- 0x%08lx\n",
+			       cur_record->timestamp,
+					cur_record->value,
+					cur_record->addr);
+
+		cur_record++;
+	}
+}
+
 static int do_set_buffer(int argc, char * const argv[])
 {
 	ulong addr = 0, size = 0;

@@ -76,6 +106,9 @@ int do_iotrace(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	case 's':
 		do_print_stats();
 		break;
+	case 'd':
+		do_print_trace();
+		break;
 	default:
 		return CMD_RET_USAGE;
 	}

@@ -90,5 +123,6 @@ U_BOOT_CMD(
 	"iotrace buffer <address> <size>      - set iotrace buffer\n"
 	"iotrace limit <address> <size>       - set iotrace region limit\n"
 	"iotrace pause                        - pause tracing\n"
-	"iotrace resume                       - resume tracing"
+	"iotrace resume                       - resume tracing\n"
+	"iotrace dump                         - dump iotrace buffer"
 );

Signature · 2 lines

The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Ramon Fried

author

2018-05-28 11:03 UTC #6 lore raw

PATCH v2 6/6 iotrace: fix behaviour when buffer is full

In reply to Ramon Fried

Don't continue updating the offset when buffer is full. When the buffer size exhausts and there's no space left to write warn the user and update only the needed size and not both the offset and needed size.

Add needed buffer size information in the iotrace command.

Signed-off-by Ramon Fried <[email protected]>

---
v2: introduced needed_size to notify the user about the needed
buffer size.

 cmd/iotrace.c     | 11 ++++++-----
 common/iotrace.c  | 13 +++++++++++--
 include/iotrace.h |  5 +++--
 3 files changed, 20 insertions(+), 9 deletions(-)

cmd/iotrace.c +6 -5

index f50a3c3a1a9..fc77f63de6a 100644
@@ -9,12 +9,13 @@
 
 static void do_print_stats(void)
 {
-	ulong start, size, offset, count;
+	ulong start, size, needed_size, offset, count;
 
 	printf("iotrace is %sabled\n", iotrace_get_enabled() ? "en" : "dis");
-	iotrace_get_buffer(&start, &size, &offset, &count);
+	iotrace_get_buffer(&start, &size, &needed_size, &offset, &count);
 	printf("Start:  %08lx\n", start);
-	printf("Size:   %08lx\n", size);
+	printf("Actual Size:   %08lx\n", size);
+	printf("Needed Size:   %08lx\n", needed_size);
 	iotrace_get_region(&start, &size);
 	printf("Region: %08lx\n", start);
 	printf("Size:   %08lx\n", size);

@@ -26,11 +27,11 @@ static void do_print_stats(void)
 
 static void do_print_trace(void)
 {
-	ulong start, size, offset, count;
+	ulong start, size, needed_size, offset, count;
 
 	struct iotrace_record *cur_record;
 
-	iotrace_get_buffer(&start, &size, &offset, &count);
+	iotrace_get_buffer(&start, &size, &needed_size, &offset, &count);
 
 	if (!start || !size || !count)
 		return;

common/iotrace.c +11 -2

index 83691b1dba9..8404638ff15 100644
@@ -15,7 +15,8 @@ DECLARE_GLOBAL_DATA_PTR;
  * struct iotrace - current trace status and checksum
  *
  * @start:	Start address of iotrace buffer
- * @size:	Size of iotrace buffer in bytes
+ * @size:	Actual size of iotrace buffer in bytes
+ * @needed_size: Needed of iotrace buffer in bytes
  * @offset:	Current write offset into iotrace buffer
  * @region_start: Address of IO region to trace
  * @region_size: Size of region to trace. if 0 will trace all address space

@@ -25,6 +26,7 @@ DECLARE_GLOBAL_DATA_PTR;
 static struct iotrace {
 	ulong start;
 	ulong size;
+	ulong needed_size;
 	ulong offset;
 	ulong region_start;
 	ulong region_size;

@@ -55,7 +57,12 @@ static void add_record(int flags, const void *ptr, ulong value)
 		rec = (struct iotrace_record *)map_sysmem(
 					iotrace.start + iotrace.offset,
 					sizeof(value));
+	} else {
+		WARN_ONCE("WARNING: iotrace buffer exhausted, please check needed length using \"iotrace stats\"\n");
+		iotrace.needed_size += sizeof(struct iotrace_record);
+		return;
 	}
+
 	rec->timestamp = timer_get_us();
 	rec->flags = flags;
 	rec->addr = map_to_sysmem(ptr);

@@ -65,6 +72,7 @@ static void add_record(int flags, const void *ptr, ulong value)
 	iotrace.crc32 = crc32(iotrace.crc32, (unsigned char *)rec,
 			      sizeof(*rec));
 
+	iotrace.needed_size += sizeof(struct iotrace_record);
 	iotrace.offset += sizeof(struct iotrace_record);
 }

@@ -162,10 +170,11 @@ void iotrace_set_buffer(ulong start, ulong size)
 	iotrace.crc32 = 0;
 }
 
-void iotrace_get_buffer(ulong *start, ulong *size, ulong *offset, ulong *count)
+void iotrace_get_buffer(ulong *start, ulong *size, ulong *needed_size, ulong *offset, ulong *count)
 {
 	*start = iotrace.start;
 	*size = iotrace.size;
+	*needed_size = iotrace.needed_size;
 	*offset = iotrace.offset;
 	*count = iotrace.offset / sizeof(struct iotrace_record);
 }

include/iotrace.h +3 -2

index b6e006ced06..ad7092e97d6 100644
@@ -146,11 +146,12 @@ void iotrace_set_buffer(ulong start, ulong size);
  * iotrace_get_buffer() - Get buffer information
  *
  * @start: Returns start address of buffer
- * @size: Returns size of buffer in bytes
+ * @size: Returns actual size of buffer in bytes
+ * @needed_size: Returns needed size of buffer in bytes
  * @offset: Returns the byte offset where the next output trace record will
  * @count: Returns the number of trace records recorded
  * be written (or would be if the buffer was large enough)
  */
-void iotrace_get_buffer(ulong *start, ulong *size, ulong *offset, ulong *count);
+void iotrace_get_buffer(ulong *start, ulong *size, ulong *needed_size, ulong *offset, ulong *count);
 
 #endif /* __IOTRACE_H */

Signature · 2 lines

The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Simon Glass

2018-05-30 19:18 UTC #7 lore raw

v3 cover Iotrace improvements

In reply to Ramon Fried

Hi Ramon,

Quoted 30 lines · Ramon Fried

These set of patches add few improvements to iotrace.
* Region limiting - allows setting an address and size where only
io operations that falls into that address are logged.
* Timestamping - Timestamp every iotrace record with current timestamp
* dumping - iotrace dump command for dumping all records from buffer
in a readable fashion.
In terms of backwards compatibility, the timestamp is not backward compatible as it changes the iotrace record. so if one developed an offline parsing tool it will be broken.
I though of adding #ifdef specific for that, but eventually I didn't.
v2:
* fixed printf format
* added a fix when the buffer is full
v3:
* changed the "buffer full" scenario as
recommended by Simon Glass.
This fix is dependand on a sperate patch that introduces WARN_ONCE definition in bug.h (https://patchwork.ozlabs.org/patch/921391/)
Ramon Fried (6):
cmd: iotrace: add set region command
iotrace: add IO region limit
common: iotrace: add timestamp to iotrace records
iotrace: move record definitons to header file
cmd: iotrace: add dump trace command
iotrace: fix behaviour when buffer is full

Quoted 4 lines

 cmd/iotrace.c     | 63 ++++++++++++++++++++++++++++++++++++++++++---
 common/iotrace.c  | 65 +++++++++++++++++++++++++++--------------------
 include/iotrace.h | 57 +++++++++++++++++++++++++++++++++++++++--
 3 files changed, 153 insertions(+), 32 deletions(-)

It looks like your patch series is a bit broken as the version number doesn't appear on the patches (e.g. 1/6), only on this cover letter.

Can you fix that? You can use patman which will do all this automatically.

Regards,
Simon

Ramon Fried

author

2018-05-30 19:23 UTC #8 lore raw

v3 cover Iotrace improvements

Ok, I'll check it out. Thanks!

Quoted 48 lines · Simon Glass

Hi Ramon,
Quoted 3 lines · Ramon Fried
These set of patches add few improvements to iotrace.
* Region limiting - allows setting an address and size where only io operations that falls into
that address are
Quoted 10 lines
logged.
* Timestamping - Timestamp every iotrace record with current timestamp
* dumping - iotrace dump command for dumping all records from buffer in a readable fashion.
In terms of backwards compatibility, the timestamp is not backward compatible as it changes the iotrace record. so if one developed an offline parsing tool it will be broken.
I though of adding #ifdef specific for that, but eventually I didn't.
Quoted 8 lines
v2:
* fixed printf format
* added a fix when the buffer is full
v3:
* changed the "buffer full" scenario as recommended by Simon Glass.
This fix is dependand on a sperate patch that introduces WARN_ONCE definition in bug.h (
https://patchwork.ozlabs.org/patch/921391/)
Quoted 9 lines
Ramon Fried (6):
cmd: iotrace: add set region command
iotrace: add IO region limit
common: iotrace: add timestamp to iotrace records
iotrace: move record definitons to header file
cmd: iotrace: add dump trace command
iotrace: fix behaviour when buffer is full
Quoted 4 lines
 cmd/iotrace.c     | 63 ++++++++++++++++++++++++++++++++++++++++++---
 common/iotrace.c  | 65 +++++++++++++++++++++++++++--------------------
 include/iotrace.h | 57 +++++++++++++++++++++++++++++++++++++++--
 3 files changed, 153 insertions(+), 32 deletions(-)
It looks like your patch series is a bit broken as the version number doesn't appear on the patches (e.g. 1/6), only on this cover letter.
Can you fix that? You can use patman which will do all this automatically.
Regards,
Simon