tracing: Fix funcgraph_exit calltime/rettime offset for 32-bit ARM

PATCH In review jempty.liang 3 participants 12 messages Feb 2 – Feb 4

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Tracing ftrace Tracing OS noise / latency tracers

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jempty.liang

author

2026-02-02 12:34 UTC #0 lore raw

PATCH v2 1/1 tracing: Fix funcgraph_exit calltime/rettime offset for 32-bit ARM

Commit <66611c0475709607f398e2a5d691b1fc72fe9dfc>
(fgraph: Remove calltime and rettime from generic)
incorrectly modified the offset values for calltime and rettime fields in the funcgraph_exit traceevent on 32-bit ARM, which are used to parse the corresponding values fromtrace rawdata. The actual memory offset of calltime is 20 (not 24), and rettime is 28 (not 32) for the funcgraph_exit event.

Before the fix,the funcgraph_exit format was:

~# cat /sys/kernel/tracing/events/ftrace/funcgraph_exit/format

name: funcgraph_exit
ID: 10
format:

    ...
    field:unsigned long long calltime; offset:24; size:8; signed:0;
    field:unsigned long long rettime; offset:32; size:8; signed:0;

After the fix, the correct funcgraph_exit format is:

name: funcgraph_exit
ID: 10
format:

    ...
    field:unsigned long long calltime; offset:20; size:8; signed:0;
    field:unsigned long long rettime; offset:28; size:8; signed:0;

Signed-off-by jempty.liang <[email protected]>

---
 include/linux/ftrace.h               |  2 ++
 kernel/trace/trace.h                 |  3 +--
 kernel/trace/trace_entries.h         |  8 +++----
 kernel/trace/trace_functions_graph.c | 31 +++++++++++++---------------
 kernel/trace/trace_irqsoff.c         |  5 +++--
 kernel/trace/trace_sched_wakeup.c    |  6 ++++--
 6 files changed, 28 insertions(+), 27 deletions(-)

include/linux/ftrace.h +2 -0

index a3a8989e3268..52727a342273 100644
@@ -1191,6 +1191,8 @@ struct ftrace_graph_ret {
 	int depth;
 	/* Number of functions that overran the depth limit for current task */
 	unsigned int overrun;
+	unsigned long long calltime;
+	unsigned long long rettime;
 } __packed;
 
 struct fgraph_ops;

kernel/trace/trace.h +1 -2

index 69e7defba6c6..18c8a0b1ecd5 100644
@@ -968,8 +968,7 @@ extern int __trace_graph_retaddr_entry(struct trace_array *tr,
 				struct ftrace_regs *fregs);
 extern void __trace_graph_return(struct trace_array *tr,
 				 struct ftrace_graph_ret *trace,
-				 unsigned int trace_ctx,
-				 u64 calltime, u64 rettime);
+				 unsigned int trace_ctx);
 
 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);

kernel/trace/trace_entries.h +4 -4

index f6a8d29c0d76..362a757e65a2 100644
@@ -127,8 +127,8 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 		__field_packed(	unsigned long,	ret,		retval	)
 		__field_packed(	unsigned int,	ret,		depth	)
 		__field_packed(	unsigned int,	ret,		overrun	)
-		__field(unsigned long long,	calltime		)
-		__field(unsigned long long,	rettime			)
+		__field_packed(unsigned long long,	ret,	calltime)
+		__field_packed(unsigned long long,	ret,	rettime)
 	),
 
 	F_printk("<-- %ps (%u) (start: %llx  end: %llx) over: %u retval: %lx",

@@ -149,8 +149,8 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 		__field_packed(	unsigned long,	ret,		func	)
 		__field_packed(	unsigned int,	ret,		depth	)
 		__field_packed(	unsigned int,	ret,		overrun	)
-		__field(unsigned long long,	calltime		)
-		__field(unsigned long long,	rettime			)
+		__field_packed(unsigned long long,	ret,	calltime)
+		__field_packed(unsigned long long,	ret,	rettime)
 	),
 
 	F_printk("<-- %ps (%u) (start: %llx  end: %llx) over: %u",

kernel/trace/trace_functions_graph.c +14 ~~-17~~

index 1de6f1573621..0d2266ec67a4 100644
@@ -317,10 +317,12 @@ __trace_graph_function(struct trace_array *tr,
 	struct ftrace_graph_ret ret = {
 		.func     = ip,
 		.depth    = 0,
+		.calltime = time,
+		.rettime = time,
 	};
 
 	__trace_graph_entry(tr, &ent, trace_ctx);
-	__trace_graph_return(tr, &ret, trace_ctx, time, time);
+	__trace_graph_return(tr, &ret, trace_ctx);
 }
 
 void

@@ -333,8 +335,7 @@ trace_graph_function(struct trace_array *tr,
 
 void __trace_graph_return(struct trace_array *tr,
 			  struct ftrace_graph_ret *trace,
-			  unsigned int trace_ctx,
-			  u64 calltime, u64 rettime)
+			  unsigned int trace_ctx)
 {
 	struct ring_buffer_event *event;
 	struct trace_buffer *buffer = tr->array_buffer.buffer;

@@ -346,8 +347,6 @@ void __trace_graph_return(struct trace_array *tr,
 		return;
 	entry	= ring_buffer_event_data(event);
 	entry->ret				= *trace;
-	entry->calltime				= calltime;
-	entry->rettime				= rettime;
 	trace_buffer_unlock_commit_nostack(buffer, event);
 }

@@ -372,10 +371,9 @@ void trace_graph_return(struct ftrace_graph_ret *trace,
 	struct trace_array *tr = gops->private;
 	struct fgraph_times *ftimes;
 	unsigned int trace_ctx;
-	u64 calltime, rettime;
 	int size;
 
-	rettime = trace_clock_local();
+	trace->rettime = trace_clock_local();
 
 	ftrace_graph_addr_finish(gops, trace);

@@ -390,10 +388,10 @@ void trace_graph_return(struct ftrace_graph_ret *trace,
 
 	handle_nosleeptime(tr, trace, ftimes, size);
 
-	calltime = ftimes->calltime;
+	trace->calltime = ftimes->calltime;
 
 	trace_ctx = tracing_gen_ctx();
-	__trace_graph_return(tr, trace, trace_ctx, calltime, rettime);
+	__trace_graph_return(tr, trace, trace_ctx);
 }
 
 static void trace_graph_thresh_return(struct ftrace_graph_ret *trace,

@@ -418,8 +416,10 @@ static void trace_graph_thresh_return(struct ftrace_graph_ret *trace,
 	tr = gops->private;
 	handle_nosleeptime(tr, trace, ftimes, size);
 
+	trace->calltime = ftimes->calltime;
+
 	if (tracing_thresh &&
-	    (trace_clock_local() - ftimes->calltime < tracing_thresh))
+	    (trace->rettime - ftimes->calltime < tracing_thresh))
 		return;
 	else
 		trace_graph_return(trace, gops, fregs);

@@ -956,7 +956,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
 
 	graph_ret = &ret_entry->ret;
 	call = &entry->graph_ent;
-	duration = ret_entry->rettime - ret_entry->calltime;
+	duration = graph_ret->rettime - graph_ret->calltime;
 
 	if (data) {
 		struct fgraph_cpu_data *cpu_data;

@@ -1275,14 +1275,11 @@ print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
 }
 
 static enum print_line_t
-print_graph_return(struct ftrace_graph_ret_entry *retentry, struct trace_seq *s,
+print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
 		   struct trace_entry *ent, struct trace_iterator *iter,
 		   u32 flags)
 {
-	struct ftrace_graph_ret *trace = &retentry->ret;
-	u64 calltime = retentry->calltime;
-	u64 rettime = retentry->rettime;
-	unsigned long long duration = rettime - calltime;
+	unsigned long long duration = trace->rettime - trace->calltime;
 	struct fgraph_data *data = iter->private;
 	struct trace_array *tr = iter->tr;
 	unsigned long func;

@@ -1482,7 +1479,7 @@ print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 	case TRACE_GRAPH_RET: {
 		struct ftrace_graph_ret_entry *field;
 		trace_assign_type(field, entry);
-		return print_graph_return(field, s, entry, iter, flags);
+		return print_graph_return(&field->ret, s, entry, iter, flags);
 	}
 	case TRACE_STACK:
 	case TRACE_FN:

kernel/trace/trace_irqsoff.c +3 -2

index 17673905907c..946be462a211 100644
@@ -229,11 +229,12 @@ static void irqsoff_graph_return(struct ftrace_graph_ret *trace,
 	if (!func_prolog_dec(tr, &data, &flags))
 		return;
 
-	rettime = trace_clock_local();
+	trace->rettime = trace_clock_local();
 	calltime = fgraph_retrieve_data(gops->idx, &size);
 	if (calltime) {
+		trace->calltime = *calltime;
 		trace_ctx = tracing_gen_ctx_flags(flags);
-		__trace_graph_return(tr, trace, trace_ctx, *calltime, rettime);
+		__trace_graph_return(tr, trace, trace_ctx);
 	}
 	local_dec(&data->disabled);
 }

kernel/trace/trace_sched_wakeup.c +4 -2

index 8faa73d3bba1..3bcfd1bf60ad 100644
@@ -164,11 +164,13 @@ static void wakeup_graph_return(struct ftrace_graph_ret *trace,
 	if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
 		return;
 
-	rettime = trace_clock_local();
+	trace->rettime = trace_clock_local();
 
 	calltime = fgraph_retrieve_data(gops->idx, &size);
-	if (calltime)
+	if (calltime) {
+		trace->calltime = *calltime;
 		__trace_graph_return(tr, trace, trace_ctx, *calltime, rettime);
+	}
 
 	local_dec(&data->disabled);
 	preempt_enable_notrace();

Signature · 1 line

2.25.1

Steven Rostedt

maintainer

2026-02-02 15:37 UTC #1 lore raw

Quoted 7 lines · On Mon, 2 Feb 2026 12:33:42 +0000 "jempty.liang" <[email protected]> wrote:

Commit <66611c0475709607f398e2a5d691b1fc72fe9dfc>
(fgraph: Remove calltime and rettime from generic)
incorrectly modified the offset values for calltime and rettime fields in the funcgraph_exit traceevent on 32-bit ARM, which are used to parse the corresponding values fromtrace rawdata. The actual memory offset of calltime is 20 (not 24), and rettime is 28 (not 32) for the funcgraph_exit event.

OK, so this is a 32bit issue and not an ARM one. I was able to reproduce it on 32bit x86 too.

Basically the problem is that the structure used to output the field offset is out of sync with the actual fields of the structure.

Quoted 12 lines

Before the fix,the funcgraph_exit format was:
~# cat /sys/kernel/tracing/events/ftrace/funcgraph_exit/format
name: funcgraph_exit
ID: 10
format:
    ...
    field:unsigned long long calltime; offset:24; size:8; signed:0;
    field:unsigned long long rettime; offset:32; size:8; signed:0;

Quoted 9 lines

After the fix, the correct funcgraph_exit format is:
name: funcgraph_exit
ID: 10
format:
    ...
    field:unsigned long long calltime; offset:20; size:8; signed:0;
    field:unsigned long long rettime; offset:28; size:8; signed:0;

Thus, the way the calltime and rettime are defined is via:

kernel/trace/trace_entries.h FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry, · line 131

Quoted 8 lines

kernel/trace/trace_entries.h +0 -2

@@ -127,8 +127,8 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 		__field_packed(	unsigned long,	ret,		retval	)
 		__field_packed(	unsigned int,	ret,		depth	)
 		__field_packed(	unsigned int,	ret,		overrun	)
-		__field(unsigned long long,	calltime		)
-		__field(unsigned long long,	rettime			)

The __field() macro.

kernel/trace/trace_entries.h FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry, · line 131

Quoted 2 lines

kernel/trace/trace_entries.h +2 -0

+		__field_packed(unsigned long long,	ret,	calltime)
+		__field_packed(unsigned long long,	ret,	rettime)

You converted it to a __field_packed() macro. The reason this worked is because fields within a structure defined by __field_packed() has an alignment of "1" to pack it.

Thus, your "fix" is simply hiding the real bug, which is that the alignment algorithm is wrong.

Can you try this patch to see if it fixes the issue for you?

Thanks,

-- Steve

kernel/trace/trace_export.c +3 -1

index 1698fc22afa0..68ef39cf0710 100644
@@ -88,7 +88,9 @@ static void __always_unused ____ftrace_check_##name(void)		\
 #undef __field_ext
 #define __field_ext(_type, _item, _filter_type) {			\
 	.type = #_type, .name = #_item,					\
-	.size = sizeof(_type), .align = __alignof__(_type),		\
+	.size = sizeof(_type),						\
+	.align = __alignof__(_type) > __alignof__(long) ? __alignof__(long) :\
+		__alignof__(_type),					\
 	is_signed_type(_type), .filter_type = _filter_type },

Steven Rostedt

maintainer

2026-02-02 16:08 UTC #2 lore raw

Quoted 1 line · On Mon, 2 Feb 2026 10:38:04 -0500 Steven Rostedt <[email protected]> wrote:

Can you try this patch to see if it fixes the issue for you?

Ignore that patch, try this one instead. This was fixed for trace_events a while ago, but the same fix wasn't done for ftrace events.

-- Steve

kernel/trace/trace_export.c +4 -1

index 1698fc22afa0..5b96ac750049 100644
@@ -14,6 +14,9 @@
 
 #include "trace_output.h"
 
+/* The alignment of a type when in a structure */
+#define ALIGN_STRUCTFIELD(type) ((int)(__alignof__(struct {type b;})))
+
 /* Stub function for events with triggers */
 static int ftrace_event_register(struct trace_event_call *call,
 				 enum trace_reg type, void *data)

@@ -88,7 +91,7 @@ static void __always_unused ____ftrace_check_##name(void)		\
 #undef __field_ext
 #define __field_ext(_type, _item, _filter_type) {			\
 	.type = #_type, .name = #_item,					\
-	.size = sizeof(_type), .align = __alignof__(_type),		\
+	.size = sizeof(_type), .align = ALIGN_STRUCTFIELD(_type),	\
 	is_signed_type(_type), .filter_type = _filter_type },

jempty.liang

author

2026-02-03 10:04 UTC #3 lore raw

Quoted 25 lines · Steven Rostedt

Quoted 1 line · On Mon, 2 Feb 2026 10:38:04 -0500 Steven Rostedt <[email protected]> wrote:
Can you try this patch to see if it fixes the issue for you?
Ignore that patch, try this one instead. This was fixed for trace_events a while ago, but the same fix wasn't done for ftrace events.
-- Steve
kernel/trace/trace_export.c +3 -0
index 1698fc22afa0..5b96ac750049 100644
@@ -14,6 +14,9 @@
 
 #include "trace_output.h"
 
+/* The alignment of a type when in a structure */
+#define ALIGN_STRUCTFIELD(type) ((int)(__alignof__(struct {type b;})))
+
 /* Stub function for events with triggers */
 static int ftrace_event_register(struct trace_event_call *call,
 				 enum trace_reg type, void *data)

kernel/trace/trace_export.c static void __always_unused ____ftrace_check_##name(void) \ · line 96

Quoted 7 lines

kernel/trace/trace_export.c +1 -1

@@ -88,7 +91,7 @@ static void __always_unused ____ftrace_check_##name(void)		\
 #undef __field_ext
 #define __field_ext(_type, _item, _filter_type) {			\
 	.type = #_type, .name = #_item,					\
-	.size = sizeof(_type), .align = __alignof__(_type),		\
+	.size = sizeof(_type), .align = ALIGN_STRUCTFIELD(_type),	\
 	is_signed_type(_type), .filter_type = _filter_type },

On the 32-bit ARM platform, when _type is unsigned long long, the resulting align value is 8 instead of the expected 4.

Quoted 1 line

Steven Rostedt

maintainer

2026-02-03 14:29 UTC #4 lore raw

Quoted 18 lines · On Tue, 3 Feb 2026 18:04:21 +0800 (CST) "jempty.liang" <[email protected]>…

Quoted 9 lines
#include "trace_output.h"
kernel/trace/trace_export.c +3 -0
+/* The alignment of a type when in a structure */
+#define ALIGN_STRUCTFIELD(type) ((int)(__alignof__(struct {type b;})))
+
/* Stub function for events with triggers */
static int ftrace_event_register(struct trace_event_call *call,
enum trace_reg type, void *data)
kernel/trace/trace_export.c static void __always_unused ____ftrace_check_##name(void) \ · line 96
Quoted 7 lines
kernel/trace/trace_export.c +1 -1
@@ -88,7 +91,7 @@ static void __always_unused ____ftrace_check_##name(void)		\
 #undef __field_ext
 #define __field_ext(_type, _item, _filter_type) {			\
 	.type = #_type, .name = #_item,					\
-	.size = sizeof(_type), .align = __alignof__(_type),		\
+	.size = sizeof(_type), .align = ALIGN_STRUCTFIELD(_type),	\
 	is_signed_type(_type), .filter_type = _filter_type },
 
On the 32-bit ARM platform, when _type is unsigned long long, the resulting align value is 8 instead of the expected 4.
Quoted 1 line

Are you saying this still doesn't work?

That would be an issue because then it would have the same bugs with generic trace events which uses the same solution.

-- Steve

Steven Rostedt

maintainer

2026-02-03 16:20 UTC #5 lore raw

Quoted 7 lines · On Tue, 3 Feb 2026 09:30:18 -0500 Steven Rostedt <[email protected]> wrote:

Quoted 2 lines
On the 32-bit ARM platform, when _type is unsigned long long, the resulting align value is 8 instead of the expected 4.
Quoted 1 line
Are you saying this still doesn't work?
That would be an issue because then it would have the same bugs with generic trace events which uses the same solution.

OK, so talking with others that know more about arm32 than I do, it can indeed still produce an 8 byte alignment.

Anyway, I still want to fix it properly. Does this patch work for you?

-- Steve

kernel/trace/trace.h +5 -2

index b6d42fe06115..c11edec5d8f5 100644
@@ -68,14 +68,17 @@ enum trace_type {
 #undef __field_fn
 #define __field_fn(type, item)		type	item;
 
+#undef __field_packed
+#define __field_packed(type, item)	type	item;
+
 #undef __field_struct
 #define __field_struct(type, item)	__field(type, item)
 
 #undef __field_desc
 #define __field_desc(type, container, item)
 
-#undef __field_packed
-#define __field_packed(type, container, item)
+#undef __field_desc_packed
+#define __field_desc_packed(type, container, item)
 
 #undef __array
 #define __array(type, item, size)	type	item[size];

kernel/trace/trace_entries.h +16 ~~-16~~

index f6a8d29c0d76..54417468fdeb 100644
@@ -79,8 +79,8 @@ FTRACE_ENTRY(funcgraph_entry, ftrace_graph_ent_entry,
 
 	F_STRUCT(
 		__field_struct(	struct ftrace_graph_ent,	graph_ent	)
-		__field_packed(	unsigned long,	graph_ent,	func		)
-		__field_packed(	unsigned long,	graph_ent,	depth		)
+		__field_desc_packed(unsigned long,	graph_ent,	func	)
+		__field_desc_packed(unsigned long,	graph_ent,	depth	)
 		__dynamic_array(unsigned long,	args				)
 	),

@@ -96,9 +96,9 @@ FTRACE_ENTRY_PACKED(fgraph_retaddr_entry, fgraph_retaddr_ent_entry,
 
 	F_STRUCT(
 		__field_struct(	struct fgraph_retaddr_ent,	graph_rent	)
-		__field_packed(	unsigned long,	graph_rent.ent,	func		)
-		__field_packed(	unsigned long,	graph_rent.ent,	depth		)
-		__field_packed(	unsigned long,	graph_rent,	retaddr		)
+		__field_desc_packed(	unsigned long,	graph_rent.ent,	func	)
+		__field_desc_packed(	unsigned long,	graph_rent.ent,	depth	)
+		__field_desc_packed(	unsigned long,	graph_rent,	retaddr	)
 		__dynamic_array(unsigned long,	args				)
 	),

@@ -123,12 +123,12 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 
 	F_STRUCT(
 		__field_struct(	struct ftrace_graph_ret,	ret	)
-		__field_packed(	unsigned long,	ret,		func	)
-		__field_packed(	unsigned long,	ret,		retval	)
-		__field_packed(	unsigned int,	ret,		depth	)
-		__field_packed(	unsigned int,	ret,		overrun	)
-		__field(unsigned long long,	calltime		)
-		__field(unsigned long long,	rettime			)
+		__field_desc_packed(	unsigned long,	ret,	func	)
+		__field_desc_packed(	unsigned long,	ret,	retval	)
+		__field_desc_packed(	unsigned int,	ret,	depth	)
+		__field_desc_packed(	unsigned int,	ret,	overrun	)
+		__field_packed(unsigned long long,	calltime)
+		__field_packed(unsigned long long,	rettime	)
 	),
 
 	F_printk("<-- %ps (%u) (start: %llx  end: %llx) over: %u retval: %lx",

@@ -146,11 +146,11 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 
 	F_STRUCT(
 		__field_struct(	struct ftrace_graph_ret,	ret	)
-		__field_packed(	unsigned long,	ret,		func	)
-		__field_packed(	unsigned int,	ret,		depth	)
-		__field_packed(	unsigned int,	ret,		overrun	)
-		__field(unsigned long long,	calltime		)
-		__field(unsigned long long,	rettime			)
+		__field_desc_packed(	unsigned long,	ret,	func	)
+		__field_desc_packed(	unsigned int,	ret,	depth	)
+		__field_desc_packed(	unsigned int,	ret,	overrun	)
+		__field_packed(unsigned long long,	calltime	)
+		__field_packed(unsigned long long,	rettime		)
 	),
 
 	F_printk("<-- %ps (%u) (start: %llx  end: %llx) over: %u",

kernel/trace/trace_export.c +15 -6

index 1698fc22afa0..32a42ef31855 100644
@@ -42,11 +42,14 @@ static int ftrace_event_register(struct trace_event_call *call,
 #undef __field_fn
 #define __field_fn(type, item)				type item;
 
+#undef __field_packed
+#define __field_packed(type, item)			type item;
+
 #undef __field_desc
 #define __field_desc(type, container, item)		type item;
 
-#undef __field_packed
-#define __field_packed(type, container, item)		type item;
+#undef __field_desc_packed
+#define __field_desc_packed(type, container, item)	type item;
 
 #undef __array
 #define __array(type, item, size)			type item[size];

@@ -104,11 +107,14 @@ static void __always_unused ____ftrace_check_##name(void)		\
 #undef __field_fn
 #define __field_fn(_type, _item) __field_ext(_type, _item, FILTER_TRACE_FN)
 
+#undef __field_packed
+#define __field_packed(_type, _item) __field_ext_packed(_type, _item, FILTER_OTHER)
+
 #undef __field_desc
 #define __field_desc(_type, _container, _item) __field_ext(_type, _item, FILTER_OTHER)
 
-#undef __field_packed
-#define __field_packed(_type, _container, _item) __field_ext_packed(_type, _item, FILTER_OTHER)
+#undef __field_desc_packed
+#define __field_desc_packed(_type, _container, _item) __field_ext_packed(_type, _item, FILTER_OTHER)
 
 #undef __array
 #define __array(_type, _item, _len) {					\

@@ -146,11 +152,14 @@ static struct trace_event_fields ftrace_event_fields_##name[] = {	\
 #undef __field_fn
 #define __field_fn(type, item)
 
+#undef __field_packed
+#define __field_packed(type, item)
+
 #undef __field_desc
 #define __field_desc(type, container, item)
 
-#undef __field_packed
-#define __field_packed(type, container, item)
+#undef __field_desc_packed
+#define __field_desc_packed(type, container, item)
 
 #undef __array
 #define __array(type, item, len)

jempty.liang

author

2026-02-04 01:21 UTC #6 lore raw

Quoted 11 lines · Steven Rostedt

Quoted 7 lines · On Tue, 3 Feb 2026 09:30:18 -0500 Steven Rostedt <[email protected]> wrote:
Quoted 2 lines
On the 32-bit ARM platform, when _type is unsigned long long, the resulting align value is 8 instead of the expected 4.
Quoted 1 line
Are you saying this still doesn't work?
That would be an issue because then it would have the same bugs with generic trace events which uses the same solution.

Quoted 6 lines

OK, so talking with others that know more about arm32 than I do, it can indeed still produce an 8 byte alignment.
Anyway, I still want to fix it properly. Does this patch work for you?
-- Steve

Yes, I've verified it and this patch works correctly on the 32-bit ARM platform.

Quoted 144 lines

kernel/trace/trace.h +5 -2

index b6d42fe06115..c11edec5d8f5 100644
@@ -68,14 +68,17 @@ enum trace_type {
 #undef __field_fn
 #define __field_fn(type, item)		type	item;
 
+#undef __field_packed
+#define __field_packed(type, item)	type	item;
+
 #undef __field_struct
 #define __field_struct(type, item)	__field(type, item)
 
 #undef __field_desc
 #define __field_desc(type, container, item)
 
-#undef __field_packed
-#define __field_packed(type, container, item)
+#undef __field_desc_packed
+#define __field_desc_packed(type, container, item)
 
 #undef __array
 #define __array(type, item, size)	type	item[size];

kernel/trace/trace_entries.h +16 ~~-16~~

index f6a8d29c0d76..54417468fdeb 100644
@@ -79,8 +79,8 @@ FTRACE_ENTRY(funcgraph_entry, ftrace_graph_ent_entry,
 
 	F_STRUCT(
 		__field_struct(	struct ftrace_graph_ent,	graph_ent	)
-		__field_packed(	unsigned long,	graph_ent,	func		)
-		__field_packed(	unsigned long,	graph_ent,	depth		)
+		__field_desc_packed(unsigned long,	graph_ent,	func	)
+		__field_desc_packed(unsigned long,	graph_ent,	depth	)
 		__dynamic_array(unsigned long,	args				)
 	),

@@ -96,9 +96,9 @@ FTRACE_ENTRY_PACKED(fgraph_retaddr_entry, fgraph_retaddr_ent_entry,
 
 	F_STRUCT(
 		__field_struct(	struct fgraph_retaddr_ent,	graph_rent	)
-		__field_packed(	unsigned long,	graph_rent.ent,	func		)
-		__field_packed(	unsigned long,	graph_rent.ent,	depth		)
-		__field_packed(	unsigned long,	graph_rent,	retaddr		)
+		__field_desc_packed(	unsigned long,	graph_rent.ent,	func	)
+		__field_desc_packed(	unsigned long,	graph_rent.ent,	depth	)
+		__field_desc_packed(	unsigned long,	graph_rent,	retaddr	)
 		__dynamic_array(unsigned long,	args				)
 	),

@@ -123,12 +123,12 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 
 	F_STRUCT(
 		__field_struct(	struct ftrace_graph_ret,	ret	)
-		__field_packed(	unsigned long,	ret,		func	)
-		__field_packed(	unsigned long,	ret,		retval	)
-		__field_packed(	unsigned int,	ret,		depth	)
-		__field_packed(	unsigned int,	ret,		overrun	)
-		__field(unsigned long long,	calltime		)
-		__field(unsigned long long,	rettime			)
+		__field_desc_packed(	unsigned long,	ret,	func	)
+		__field_desc_packed(	unsigned long,	ret,	retval	)
+		__field_desc_packed(	unsigned int,	ret,	depth	)
+		__field_desc_packed(	unsigned int,	ret,	overrun	)
+		__field_packed(unsigned long long,	calltime)
+		__field_packed(unsigned long long,	rettime	)
 	),
 
 	F_printk("<-- %ps (%u) (start: %llx  end: %llx) over: %u retval: %lx",

@@ -146,11 +146,11 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 
 	F_STRUCT(
 		__field_struct(	struct ftrace_graph_ret,	ret	)
-		__field_packed(	unsigned long,	ret,		func	)
-		__field_packed(	unsigned int,	ret,		depth	)
-		__field_packed(	unsigned int,	ret,		overrun	)
-		__field(unsigned long long,	calltime		)
-		__field(unsigned long long,	rettime			)
+		__field_desc_packed(	unsigned long,	ret,	func	)
+		__field_desc_packed(	unsigned int,	ret,	depth	)
+		__field_desc_packed(	unsigned int,	ret,	overrun	)
+		__field_packed(unsigned long long,	calltime	)
+		__field_packed(unsigned long long,	rettime		)
 	),
 
 	F_printk("<-- %ps (%u) (start: %llx  end: %llx) over: %u",

kernel/trace/trace_export.c +15 -6

index 1698fc22afa0..32a42ef31855 100644
@@ -42,11 +42,14 @@ static int ftrace_event_register(struct trace_event_call *call,
 #undef __field_fn
 #define __field_fn(type, item)				type item;
 
+#undef __field_packed
+#define __field_packed(type, item)			type item;
+
 #undef __field_desc
 #define __field_desc(type, container, item)		type item;
 
-#undef __field_packed
-#define __field_packed(type, container, item)		type item;
+#undef __field_desc_packed
+#define __field_desc_packed(type, container, item)	type item;
 
 #undef __array
 #define __array(type, item, size)			type item[size];

@@ -104,11 +107,14 @@ static void __always_unused ____ftrace_check_##name(void)		\
 #undef __field_fn
 #define __field_fn(_type, _item) __field_ext(_type, _item, FILTER_TRACE_FN)
 
+#undef __field_packed
+#define __field_packed(_type, _item) __field_ext_packed(_type, _item, FILTER_OTHER)
+
 #undef __field_desc
 #define __field_desc(_type, _container, _item) __field_ext(_type, _item, FILTER_OTHER)
 
-#undef __field_packed
-#define __field_packed(_type, _container, _item) __field_ext_packed(_type, _item, FILTER_OTHER)
+#undef __field_desc_packed
+#define __field_desc_packed(_type, _container, _item) __field_ext_packed(_type, _item, FILTER_OTHER)
 
 #undef __array
 #define __array(_type, _item, _len) {					\

@@ -146,11 +152,14 @@ static struct trace_event_fields ftrace_event_fields_##name[] = {	\
 #undef __field_fn
 #define __field_fn(type, item)
 
+#undef __field_packed
+#define __field_packed(type, item)
+
 #undef __field_desc
 #define __field_desc(type, container, item)
 
-#undef __field_packed
-#define __field_packed(type, container, item)
+#undef __field_desc_packed
+#define __field_desc_packed(type, container, item)
 
 #undef __array
 #define __array(type, item, len)

jempty.liang

author

2026-02-03 09:43 UTC #7 lore raw

In reply to Steven Rostedt

Quoted 74 lines · Steven Rostedt

Quoted 7 lines · On Mon, 2 Feb 2026 12:33:42 +0000 "jempty.liang" <[email protected]> wrote:
Commit <66611c0475709607f398e2a5d691b1fc72fe9dfc>
(fgraph: Remove calltime and rettime from generic)
incorrectly modified the offset values for calltime and rettime fields in the funcgraph_exit traceevent on 32-bit ARM, which are used to parse the corresponding values fromtrace rawdata. The actual memory offset of calltime is 20 (not 24), and rettime is 28 (not 32) for the funcgraph_exit event.
OK, so this is a 32bit issue and not an ARM one. I was able to reproduce it on 32bit x86 too.
Basically the problem is that the structure used to output the field offset is out of sync with the actual fields of the structure.
Quoted 12 lines
Before the fix,the funcgraph_exit format was:
~# cat /sys/kernel/tracing/events/ftrace/funcgraph_exit/format
name: funcgraph_exit
ID: 10
format:
    ...
    field:unsigned long long calltime; offset:24; size:8; signed:0;
    field:unsigned long long rettime; offset:32; size:8; signed:0;
Quoted 9 lines
After the fix, the correct funcgraph_exit format is:
name: funcgraph_exit
ID: 10
format:
    ...
    field:unsigned long long calltime; offset:20; size:8; signed:0;
    field:unsigned long long rettime; offset:28; size:8; signed:0;
Thus, the way the calltime and rettime are defined is via:
kernel/trace/trace_entries.h FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry, · line 131
Quoted 8 lines
kernel/trace/trace_entries.h +0 -2
@@ -127,8 +127,8 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 		__field_packed(	unsigned long,	ret,		retval	)
 		__field_packed(	unsigned int,	ret,		depth	)
 		__field_packed(	unsigned int,	ret,		overrun	)
-		__field(unsigned long long,	calltime		)
-		__field(unsigned long long,	rettime			)
The __field() macro.
kernel/trace/trace_entries.h FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry, · line 131
Quoted 2 lines
kernel/trace/trace_entries.h +2 -0
+		__field_packed(unsigned long long,	ret,	calltime)
+		__field_packed(unsigned long long,	ret,	rettime)
You converted it to a __field_packed() macro. The reason this worked is because fields within a structure defined by __field_packed() has an alignment of "1" to pack it.
Thus, your "fix" is simply hiding the real bug, which is that the alignment algorithm is wrong.
Can you try this patch to see if it fixes the issue for you?
Thanks,
-- Steve
kernel/trace/trace_export.c +0 -0
index 1698fc22afa0..68ef39cf0710 100644

kernel/trace/trace_export.c static void __always_unused ____ftrace_check_##name(void) \ · line 96

Quoted 10 lines

kernel/trace/trace_export.c +3 -1

@@ -88,7 +88,9 @@ static void __always_unused ____ftrace_check_##name(void)		\
 #undef __field_ext
 #define __field_ext(_type, _item, _filter_type) {			\
 	.type = #_type, .name = #_item,					\
-	.size = sizeof(_type), .align = __alignof__(_type),		\
+	.size = sizeof(_type),						\
+	.align = __alignof__(_type) > __alignof__(long) ? __alignof__(long) :\
+		__alignof__(_type),					\
 	is_signed_type(_type), .filter_type = _filter_type },

It works on the 32-bit ARM platform.

kernel test robot

build bot

2026-02-03 04:06 UTC #8 lore raw

In reply to jempty.liang

kernel test robot noticed the following build warnings:

Hi jempty.liang,

kernel test robot noticed the following build warnings:

[auto build test WARNING on trace/for-next]
[also build test WARNING on linus/master v6.19-rc8 next-20260202] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/jempty-liang/tracing-Fix-funcgraph_exit-calltime-rettime-offset-for-32-bit-ARM/20260202-203926
base:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace for-next
patch link:    https://lore.kernel.org/r/20260202123342.2544795-1-imntjempty%40163.com
patch subject: [PATCH v2] tracing: Fix funcgraph_exit calltime/rettime offset for 32-bit ARM
config: x86_64-buildonly-randconfig-004-20260203 (https://download.01.org/0day-ci/archive/20260203/[email protected]/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260203/[email protected]/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All warnings (new ones prefixed by >>):

kernel/trace/trace_irqsoff.c: In function 'irqsoff_graph_return':

>> kernel/trace/trace_irqsoff.c:224:13: warning: unused variable 'rettime' [-Wunused-variable]
     224 |         u64 rettime;
         |             ^~~~~~~

vim +/rettime +224 kernel/trace/trace_irqsoff.c

62b915f1060996 Jiri Olsa                 2010-04-02  214  
37238abe3cb47b Steven Rostedt (VMware    2024-06-03  215) static void irqsoff_graph_return(struct ftrace_graph_ret *trace,
2ca8c112c9676e Masami Hiramatsu (Google  2024-12-26  216) 				 struct fgraph_ops *gops,
2ca8c112c9676e Masami Hiramatsu (Google  2024-12-26  217) 				 struct ftrace_regs *fregs)
62b915f1060996 Jiri Olsa                 2010-04-02  218  {
62b915f1060996 Jiri Olsa                 2010-04-02  219  	struct trace_array *tr = irqsoff_trace;
62b915f1060996 Jiri Olsa                 2010-04-02  220  	struct trace_array_cpu *data;
62b915f1060996 Jiri Olsa                 2010-04-02  221  	unsigned long flags;
36590c50b2d072 Sebastian Andrzej Siewior 2021-01-25  222  	unsigned int trace_ctx;
a485ea9e3ef31a Steven Rostedt            2025-01-13  223  	u64 *calltime;
66611c04757096 Steven Rostedt            2025-01-21 @224  	u64 rettime;
a485ea9e3ef31a Steven Rostedt            2025-01-13  225  	int size;
62b915f1060996 Jiri Olsa                 2010-04-02  226  
12117f3307b63f Steven Rostedt (VMware    2024-06-03  227) 	ftrace_graph_addr_finish(gops, trace);
5cf99a0f3161bc Steven Rostedt (VMware    2018-11-29  228) 
5e6d2b9cfa3a6e Steven Rostedt            2010-10-05  229  	if (!func_prolog_dec(tr, &data, &flags))
62b915f1060996 Jiri Olsa                 2010-04-02  230  		return;
62b915f1060996 Jiri Olsa                 2010-04-02  231  
77a67833e830fd jempty.liang              2026-02-02  232  	trace->rettime = trace_clock_local();
a485ea9e3ef31a Steven Rostedt            2025-01-13  233  	calltime = fgraph_retrieve_data(gops->idx, &size);
c834a97962c708 Steven Rostedt            2025-10-08  234  	if (calltime) {
77a67833e830fd jempty.liang              2026-02-02  235  		trace->calltime = *calltime;
36590c50b2d072 Sebastian Andrzej Siewior 2021-01-25  236  		trace_ctx = tracing_gen_ctx_flags(flags);
77a67833e830fd jempty.liang              2026-02-02  237  		__trace_graph_return(tr, trace, trace_ctx);
c834a97962c708 Steven Rostedt            2025-10-08  238  	}
90633c34c36d0c Steven Rostedt            2025-05-05  239  	local_dec(&data->disabled);
62b915f1060996 Jiri Olsa                 2010-04-02  240  }
62b915f1060996 Jiri Olsa                 2010-04-02  241

Signature · 2 lines

0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

kernel test robot

build bot

2026-02-03 04:27 UTC #9 lore raw

In reply to jempty.liang

kernel test robot noticed the following build errors:

Hi jempty.liang,

kernel test robot noticed the following build errors:

[auto build test ERROR on trace/for-next]
[also build test ERROR on linus/master v6.19-rc8 next-20260202] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/jempty-liang/tracing-Fix-funcgraph_exit-calltime-rettime-offset-for-32-bit-ARM/20260202-203926
base:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace for-next
patch link:    https://lore.kernel.org/r/20260202123342.2544795-1-imntjempty%40163.com
patch subject: [PATCH v2] tracing: Fix funcgraph_exit calltime/rettime offset for 32-bit ARM
config: sh-allmodconfig (https://download.01.org/0day-ci/archive/20260203/[email protected]/config)
compiler: sh4-linux-gcc (GCC) 15.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260203/[email protected]/reproduce)

All errors (new ones prefixed by >>):

kernel/trace/trace_sched_wakeup.c: In function 'wakeup_graph_return':

>> kernel/trace/trace_sched_wakeup.c:172:17: error: too many arguments to function '__trace_graph_return'; expected 3, have 5
     172 |                 __trace_graph_return(tr, trace, trace_ctx, *calltime, rettime);
         |                 ^~~~~~~~~~~~~~~~~~~~                       ~~~~~~~~~

In file included from kernel/trace/trace_sched_wakeup.c:20:
kernel/trace/trace.h:969:13: note: declared here
969 | extern void __trace_graph_return(struct trace_array *tr,
| ^~~~~~~~~~~~~~~~~~~~

vim +/__trace_graph_return +172 kernel/trace/trace_sched_wakeup.c

7495a5beaa22f1 Jiri Olsa                 2010-09-23  150  
37238abe3cb47b Steven Rostedt (VMware    2024-06-03  151) static void wakeup_graph_return(struct ftrace_graph_ret *trace,
2ca8c112c9676e Masami Hiramatsu (Google  2024-12-26  152) 				struct fgraph_ops *gops,
2ca8c112c9676e Masami Hiramatsu (Google  2024-12-26  153) 				struct ftrace_regs *fregs)
7495a5beaa22f1 Jiri Olsa                 2010-09-23  154  {
7495a5beaa22f1 Jiri Olsa                 2010-09-23  155  	struct trace_array *tr = wakeup_trace;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  156  	struct trace_array_cpu *data;
36590c50b2d072 Sebastian Andrzej Siewior 2021-01-25  157  	unsigned int trace_ctx;
a485ea9e3ef31a Steven Rostedt            2025-01-13  158  	u64 *calltime;
66611c04757096 Steven Rostedt            2025-01-21  159  	u64 rettime;
a485ea9e3ef31a Steven Rostedt            2025-01-13  160  	int size;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  161  
12117f3307b63f Steven Rostedt (VMware    2024-06-03  162) 	ftrace_graph_addr_finish(gops, trace);
5cf99a0f3161bc Steven Rostedt (VMware    2018-11-29  163) 
36590c50b2d072 Sebastian Andrzej Siewior 2021-01-25  164  	if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
7495a5beaa22f1 Jiri Olsa                 2010-09-23  165  		return;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  166  
77a67833e830fd jempty.liang              2026-02-02  167  	trace->rettime = trace_clock_local();
66611c04757096 Steven Rostedt            2025-01-21  168  
a485ea9e3ef31a Steven Rostedt            2025-01-13  169  	calltime = fgraph_retrieve_data(gops->idx, &size);
77a67833e830fd jempty.liang              2026-02-02  170  	if (calltime) {
77a67833e830fd jempty.liang              2026-02-02  171  		trace->calltime = *calltime;
66611c04757096 Steven Rostedt            2025-01-21 @172  		__trace_graph_return(tr, trace, trace_ctx, *calltime, rettime);
77a67833e830fd jempty.liang              2026-02-02  173  	}
7495a5beaa22f1 Jiri Olsa                 2010-09-23  174  
4f7bf54b07e5ac Steven Rostedt            2025-10-08  175  	local_dec(&data->disabled);
7495a5beaa22f1 Jiri Olsa                 2010-09-23  176  	preempt_enable_notrace();
7495a5beaa22f1 Jiri Olsa                 2010-09-23  177  	return;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  178  }
7495a5beaa22f1 Jiri Olsa                 2010-09-23  179

Signature · 2 lines

0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

kernel test robot

build bot

2026-02-03 05:50 UTC #10 lore raw

In reply to jempty.liang

kernel test robot noticed the following build errors:

Hi jempty.liang,

kernel test robot noticed the following build errors:

url:    https://github.com/intel-lab-lkp/linux/commits/jempty-liang/tracing-Fix-funcgraph_exit-calltime-rettime-offset-for-32-bit-ARM/20260202-203926
base:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace for-next
patch link:    https://lore.kernel.org/r/20260202123342.2544795-1-imntjempty%40163.com
patch subject: [PATCH v2] tracing: Fix funcgraph_exit calltime/rettime offset for 32-bit ARM
config: x86_64-rhel-9.4-rust (https://download.01.org/0day-ci/archive/20260203/[email protected]/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
rustc: rustc 1.88.0 (6b00bc388 2025-06-23)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260203/[email protected]/reproduce)

All errors (new ones prefixed by >>):

>> kernel/trace/trace_sched_wakeup.c:172:46: error: too many arguments to function call, expected 3, have 5
     172 |                 __trace_graph_return(tr, trace, trace_ctx, *calltime, rettime);
         |                 ~~~~~~~~~~~~~~~~~~~~                       ^~~~~~~~~~~~~~~~~~
   kernel/trace/trace.h:969:13: note: '__trace_graph_return' declared here
     969 | extern void __trace_graph_return(struct trace_array *tr,
         |             ^                    ~~~~~~~~~~~~~~~~~~~~~~~
     970 |                                  struct ftrace_graph_ret *trace,
         |                                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     971 |                                  unsigned int trace_ctx);
         |                                  ~~~~~~~~~~~~~~~~~~~~~~

1 error generated.

vim +172 kernel/trace/trace_sched_wakeup.c

7495a5beaa22f1 Jiri Olsa                 2010-09-23  150  
37238abe3cb47b Steven Rostedt (VMware    2024-06-03  151) static void wakeup_graph_return(struct ftrace_graph_ret *trace,
2ca8c112c9676e Masami Hiramatsu (Google  2024-12-26  152) 				struct fgraph_ops *gops,
2ca8c112c9676e Masami Hiramatsu (Google  2024-12-26  153) 				struct ftrace_regs *fregs)
7495a5beaa22f1 Jiri Olsa                 2010-09-23  154  {
7495a5beaa22f1 Jiri Olsa                 2010-09-23  155  	struct trace_array *tr = wakeup_trace;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  156  	struct trace_array_cpu *data;
36590c50b2d072 Sebastian Andrzej Siewior 2021-01-25  157  	unsigned int trace_ctx;
a485ea9e3ef31a Steven Rostedt            2025-01-13  158  	u64 *calltime;
66611c04757096 Steven Rostedt            2025-01-21  159  	u64 rettime;
a485ea9e3ef31a Steven Rostedt            2025-01-13  160  	int size;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  161  
12117f3307b63f Steven Rostedt (VMware    2024-06-03  162) 	ftrace_graph_addr_finish(gops, trace);
5cf99a0f3161bc Steven Rostedt (VMware    2018-11-29  163) 
36590c50b2d072 Sebastian Andrzej Siewior 2021-01-25  164  	if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
7495a5beaa22f1 Jiri Olsa                 2010-09-23  165  		return;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  166  
77a67833e830fd jempty.liang              2026-02-02  167  	trace->rettime = trace_clock_local();
66611c04757096 Steven Rostedt            2025-01-21  168  
a485ea9e3ef31a Steven Rostedt            2025-01-13  169  	calltime = fgraph_retrieve_data(gops->idx, &size);
77a67833e830fd jempty.liang              2026-02-02  170  	if (calltime) {
77a67833e830fd jempty.liang              2026-02-02  171  		trace->calltime = *calltime;
66611c04757096 Steven Rostedt            2025-01-21 @172  		__trace_graph_return(tr, trace, trace_ctx, *calltime, rettime);
77a67833e830fd jempty.liang              2026-02-02  173  	}
7495a5beaa22f1 Jiri Olsa                 2010-09-23  174  
4f7bf54b07e5ac Steven Rostedt            2025-10-08  175  	local_dec(&data->disabled);
7495a5beaa22f1 Jiri Olsa                 2010-09-23  176  	preempt_enable_notrace();
7495a5beaa22f1 Jiri Olsa                 2010-09-23  177  	return;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  178  }
7495a5beaa22f1 Jiri Olsa                 2010-09-23  179

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0-DAY CI Kernel Test Service
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kernel test robot

build bot

2026-02-03 07:18 UTC #11 lore raw

In reply to jempty.liang

kernel test robot noticed the following build errors:

Hi jempty.liang,

kernel test robot noticed the following build errors:

[auto build test ERROR on trace/for-next]
[also build test ERROR on next-20260202]
[cannot apply to linus/master v6.16-rc1]
[If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/jempty-liang/tracing-Fix-funcgraph_exit-calltime-rettime-offset-for-32-bit-ARM/20260202-203926
base:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace for-next
patch link:    https://lore.kernel.org/r/20260202123342.2544795-1-imntjempty%40163.com
patch subject: [PATCH v2] tracing: Fix funcgraph_exit calltime/rettime offset for 32-bit ARM
config: i386-allnoconfig-bpf (https://download.01.org/0day-ci/archive/20260203/[email protected]/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260203/[email protected]/reproduce)

All error/warnings (new ones prefixed by >>):

>> kernel/trace/trace_irqsoff.c:224:6: warning: unused variable 'rettime' [-Wunused-variable]
     224 |         u64 rettime;
         |             ^~~~~~~
   1 warning generated.
--
>> kernel/trace/trace_sched_wakeup.c:172:46: error: too many arguments to function call, expected 3, have 5
     172 |                 __trace_graph_return(tr, trace, trace_ctx, *calltime, rettime);
         |                 ~~~~~~~~~~~~~~~~~~~~                       ^~~~~~~~~~~~~~~~~~
   kernel/trace/trace.h:969:13: note: '__trace_graph_return' declared here
     969 | extern void __trace_graph_return(struct trace_array *tr,
         |             ^                    ~~~~~~~~~~~~~~~~~~~~~~~
     970 |                                  struct ftrace_graph_ret *trace,
         |                                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     971 |                                  unsigned int trace_ctx);
         |                                  ~~~~~~~~~~~~~~~~~~~~~~

1 error generated.

vim +172 kernel/trace/trace_sched_wakeup.c

7495a5beaa22f1 Jiri Olsa                 2010-09-23  150  
37238abe3cb47b Steven Rostedt (VMware    2024-06-03  151) static void wakeup_graph_return(struct ftrace_graph_ret *trace,
2ca8c112c9676e Masami Hiramatsu (Google  2024-12-26  152) 				struct fgraph_ops *gops,
2ca8c112c9676e Masami Hiramatsu (Google  2024-12-26  153) 				struct ftrace_regs *fregs)
7495a5beaa22f1 Jiri Olsa                 2010-09-23  154  {
7495a5beaa22f1 Jiri Olsa                 2010-09-23  155  	struct trace_array *tr = wakeup_trace;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  156  	struct trace_array_cpu *data;
36590c50b2d072 Sebastian Andrzej Siewior 2021-01-25  157  	unsigned int trace_ctx;
a485ea9e3ef31a Steven Rostedt            2025-01-13  158  	u64 *calltime;
66611c04757096 Steven Rostedt            2025-01-21  159  	u64 rettime;
a485ea9e3ef31a Steven Rostedt            2025-01-13  160  	int size;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  161  
12117f3307b63f Steven Rostedt (VMware    2024-06-03  162) 	ftrace_graph_addr_finish(gops, trace);
5cf99a0f3161bc Steven Rostedt (VMware    2018-11-29  163) 
36590c50b2d072 Sebastian Andrzej Siewior 2021-01-25  164  	if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
7495a5beaa22f1 Jiri Olsa                 2010-09-23  165  		return;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  166  
77a67833e830fd jempty.liang              2026-02-02  167  	trace->rettime = trace_clock_local();
66611c04757096 Steven Rostedt            2025-01-21  168  
a485ea9e3ef31a Steven Rostedt            2025-01-13  169  	calltime = fgraph_retrieve_data(gops->idx, &size);
77a67833e830fd jempty.liang              2026-02-02  170  	if (calltime) {
77a67833e830fd jempty.liang              2026-02-02  171  		trace->calltime = *calltime;
66611c04757096 Steven Rostedt            2025-01-21 @172  		__trace_graph_return(tr, trace, trace_ctx, *calltime, rettime);
77a67833e830fd jempty.liang              2026-02-02  173  	}
7495a5beaa22f1 Jiri Olsa                 2010-09-23  174  
4f7bf54b07e5ac Steven Rostedt            2025-10-08  175  	local_dec(&data->disabled);
7495a5beaa22f1 Jiri Olsa                 2010-09-23  176  	preempt_enable_notrace();
7495a5beaa22f1 Jiri Olsa                 2010-09-23  177  	return;
7495a5beaa22f1 Jiri Olsa                 2010-09-23  178  }
7495a5beaa22f1 Jiri Olsa                 2010-09-23  179

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0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki