tracing: Minor fixes and clean ups

PATCH New Steven Rostedt 1 participant 6 messages Jul 11, 2023

Subsystems (5)

Stable branch x86 arm64 Tracing +1 more subsystems

lore

Share & tools

lore

Steven Rostedt

author maintainer

2023-07-11 14:07 UTC #0 lore raw

cover tracing: Minor fixes and clean ups

Tracing fixes and clean ups:

- Fix some missing-prototype warnings

- Fix user events struct args (did not include size of struct) When creating a user event, the "struct" keyword is to denote that the size of the field will be passed in. But the parsing failed to handle this case.

- Fix sample code for direct trampolines.
The sample code for direct trampolines attached to handle_mm_fault(). But the prototype changed and the direct trampoline sample code was not updated. Direct trampolines needs to have the arguments correct otherwise it can fail or crash the system.

- Remove unused ftrace_regs_caller_ret() prototype.

git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
trace/core

Head SHA1: 46b77ea28faeed56f1d1b63f9049c40b9eb3cbf5

Arnd Bergmann (1):
tracing: arm64: Avoid missing-prototype warnings

Beau Belgrave (1):
tracing/user_events: Fix struct arg size match check

Florent Revest (2):
samples: ftrace: Save required argument registers in sample trampolines
arm64: ftrace: Add direct call trampoline samples support

YueHaibing (1):
x86/ftrace: Remove unsued extern declaration ftrace_regs_caller_ret()

----

 arch/arm64/Kconfig                          |  2 ++
 arch/arm64/include/asm/ftrace.h             |  4 +++
 arch/arm64/include/asm/syscall.h            |  3 +++
 arch/arm64/kernel/syscall.c                 |  3 ---
 arch/x86/kernel/ftrace.c                    |  1 -
 include/linux/ftrace.h                      |  8 ++++++
 kernel/trace/fgraph.c                       |  1 +
 kernel/trace/ftrace_internal.h              |  5 ++--
 kernel/trace/trace_events_user.c            |  3 +++
 kernel/trace/trace_kprobe_selftest.c        |  3 +++
 samples/ftrace/ftrace-direct-modify.c       | 34 ++++++++++++++++++++++++
 samples/ftrace/ftrace-direct-multi-modify.c | 40 +++++++++++++++++++++++++++++
 samples/ftrace/ftrace-direct-multi.c        | 25 ++++++++++++++++++
 samples/ftrace/ftrace-direct-too.c          | 40 ++++++++++++++++++++++++-----
 samples/ftrace/ftrace-direct.c              | 24 +++++++++++++++++
 15 files changed, 184 insertions(+), 12 deletions(-)

Steven Rostedt

author maintainer

2023-07-11 14:07 UTC #1 lore raw

PATCH 1/5 samples: ftrace: Save required argument registers in sample trampolines

From: Florent Revest <[email protected]>

The ftrace-direct-too sample traces the handle_mm_fault function whose signature changed since the introduction of the sample. Since:
commit bce617edecad ("mm: do page fault accounting in handle_mm_fault") handle_mm_fault now has 4 arguments. Therefore, the sample trampoline should save 4 argument registers.

s390 saves all argument registers already so it does not need a change but x86_64 needs an extra push and pop.

This also evolves the signature of the tracing function to make it mirror the signature of the traced function.

Link https://lkml.kernel.org/r/[email protected] open here

Cc [email protected]

Fixes bce617edecad ("mm: do page fault accounting in handle_mm_fault")

Reviewed-by Steven Rostedt (Google) <[email protected]>

Reviewed-by Mark Rutland <[email protected]>

Acked-by Catalin Marinas <[email protected]>

Signed-off-by Florent Revest <[email protected]>

Signed-off-by Steven Rostedt (Google) <[email protected]>

---
 samples/ftrace/ftrace-direct-too.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

samples/ftrace/ftrace-direct-too.c +8 -6

index a05bc2cc2261..7986033887f6 100644
@@ -5,14 +5,14 @@
 #include <linux/ftrace.h>
 #include <asm/asm-offsets.h>
 
-extern void my_direct_func(struct vm_area_struct *vma,
-			   unsigned long address, unsigned int flags);
+extern void my_direct_func(struct vm_area_struct *vma, unsigned long address,
+			   unsigned int flags, struct pt_regs *regs);
 
-void my_direct_func(struct vm_area_struct *vma,
-			unsigned long address, unsigned int flags)
+void my_direct_func(struct vm_area_struct *vma, unsigned long address,
+		    unsigned int flags, struct pt_regs *regs)
 {
-	trace_printk("handle mm fault vma=%p address=%lx flags=%x\n",
-		     vma, address, flags);
+	trace_printk("handle mm fault vma=%p address=%lx flags=%x regs=%p\n",
+		     vma, address, flags, regs);
 }
 
 extern void my_tramp(void *);

@@ -34,7 +34,9 @@ asm (
 "	pushq %rdi\n"
 "	pushq %rsi\n"
 "	pushq %rdx\n"
+"	pushq %rcx\n"
 "	call my_direct_func\n"
+"	popq %rcx\n"
 "	popq %rdx\n"
 "	popq %rsi\n"
 "	popq %rdi\n"

Signature · 1 line

2.40.1

Steven Rostedt

author maintainer

2023-07-11 14:07 UTC #2 lore raw

PATCH 2/5 arm64: ftrace: Add direct call trampoline samples support

In reply to Steven Rostedt

From: Florent Revest <[email protected]>

The ftrace samples need per-architecture trampoline implementations to save and restore argument registers around the calls to my_direct_func* and to restore polluted registers (eg: x30).

These samples also include <asm/asm-offsets.h> which, on arm64, is not necessary and redefines previously defined macros (resulting in warnings) so these includes are guarded by !CONFIG_ARM64.

Link https://lkml.kernel.org/r/[email protected] open here

Reviewed-by Mark Rutland <[email protected]>

Tested-by Mark Rutland <[email protected]>

Acked-by Catalin Marinas <[email protected]>

Signed-off-by Florent Revest <[email protected]>

Signed-off-by Steven Rostedt (Google) <[email protected]>

---
 arch/arm64/Kconfig                          |  2 ++
 samples/ftrace/ftrace-direct-modify.c       | 34 ++++++++++++++++++
 samples/ftrace/ftrace-direct-multi-modify.c | 40 +++++++++++++++++++++
 samples/ftrace/ftrace-direct-multi.c        | 25 +++++++++++++
 samples/ftrace/ftrace-direct-too.c          | 26 ++++++++++++++
 samples/ftrace/ftrace-direct.c              | 24 +++++++++++++
 6 files changed, 151 insertions(+)

arch/arm64/Kconfig +2 -0

index f90b1780ea6c..d4421356bb3a 100644
@@ -196,6 +196,8 @@ config ARM64
 		    !CC_OPTIMIZE_FOR_SIZE)
 	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
 		if DYNAMIC_FTRACE_WITH_ARGS
+	select HAVE_SAMPLE_FTRACE_DIRECT
+	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
 	select HAVE_EFFICIENT_UNALIGNED_ACCESS
 	select HAVE_FAST_GUP
 	select HAVE_FTRACE_MCOUNT_RECORD

samples/ftrace/ftrace-direct-modify.c +34 -0

index 06d889149012..e5ed08098ff3 100644
@@ -2,7 +2,9 @@
 #include <linux/module.h>
 #include <linux/kthread.h>
 #include <linux/ftrace.h>
+#ifndef CONFIG_ARM64
 #include <asm/asm-offsets.h>
+#endif
 
 extern void my_direct_func1(void);
 extern void my_direct_func2(void);

@@ -96,6 +98,38 @@ asm (
 
 #endif /* CONFIG_S390 */
 
+#ifdef CONFIG_ARM64
+
+asm (
+"	.pushsection    .text, \"ax\", @progbits\n"
+"	.type		my_tramp1, @function\n"
+"	.globl		my_tramp1\n"
+"   my_tramp1:"
+"	bti	c\n"
+"	sub	sp, sp, #16\n"
+"	stp	x9, x30, [sp]\n"
+"	bl	my_direct_func1\n"
+"	ldp	x30, x9, [sp]\n"
+"	add	sp, sp, #16\n"
+"	ret	x9\n"
+"	.size		my_tramp1, .-my_tramp1\n"
+
+"	.type		my_tramp2, @function\n"
+"	.globl		my_tramp2\n"
+"   my_tramp2:"
+"	bti	c\n"
+"	sub	sp, sp, #16\n"
+"	stp	x9, x30, [sp]\n"
+"	bl	my_direct_func2\n"
+"	ldp	x30, x9, [sp]\n"
+"	add	sp, sp, #16\n"
+"	ret	x9\n"
+"	.size		my_tramp2, .-my_tramp2\n"
+"	.popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
 #ifdef CONFIG_LOONGARCH
 
 asm (

samples/ftrace/ftrace-direct-multi-modify.c +40 -0

index 62f6b681999e..292cff2b3f5d 100644
@@ -2,7 +2,9 @@
 #include <linux/module.h>
 #include <linux/kthread.h>
 #include <linux/ftrace.h>
+#ifndef CONFIG_ARM64
 #include <asm/asm-offsets.h>
+#endif
 
 extern void my_direct_func1(unsigned long ip);
 extern void my_direct_func2(unsigned long ip);

@@ -103,6 +105,44 @@ asm (
 
 #endif /* CONFIG_S390 */
 
+#ifdef CONFIG_ARM64
+
+asm (
+"	.pushsection    .text, \"ax\", @progbits\n"
+"	.type		my_tramp1, @function\n"
+"	.globl		my_tramp1\n"
+"   my_tramp1:"
+"	bti	c\n"
+"	sub	sp, sp, #32\n"
+"	stp	x9, x30, [sp]\n"
+"	str	x0, [sp, #16]\n"
+"	mov	x0, x30\n"
+"	bl	my_direct_func1\n"
+"	ldp	x30, x9, [sp]\n"
+"	ldr	x0, [sp, #16]\n"
+"	add	sp, sp, #32\n"
+"	ret	x9\n"
+"	.size		my_tramp1, .-my_tramp1\n"
+
+"	.type		my_tramp2, @function\n"
+"	.globl		my_tramp2\n"
+"   my_tramp2:"
+"	bti	c\n"
+"	sub	sp, sp, #32\n"
+"	stp	x9, x30, [sp]\n"
+"	str	x0, [sp, #16]\n"
+"	mov	x0, x30\n"
+"	bl	my_direct_func2\n"
+"	ldp	x30, x9, [sp]\n"
+"	ldr	x0, [sp, #16]\n"
+"	add	sp, sp, #32\n"
+"	ret	x9\n"
+"	.size		my_tramp2, .-my_tramp2\n"
+"	.popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
 #ifdef CONFIG_LOONGARCH
 #include <asm/asm.h>

samples/ftrace/ftrace-direct-multi.c +25 -0

index 5482cf616b43..b4391e08c913 100644
@@ -4,7 +4,9 @@
 #include <linux/mm.h> /* for handle_mm_fault() */
 #include <linux/ftrace.h>
 #include <linux/sched/stat.h>
+#ifndef CONFIG_ARM64
 #include <asm/asm-offsets.h>
+#endif
 
 extern void my_direct_func(unsigned long ip);

@@ -66,6 +68,29 @@ asm (
 
 #endif /* CONFIG_S390 */
 
+#ifdef CONFIG_ARM64
+
+asm (
+"	.pushsection	.text, \"ax\", @progbits\n"
+"	.type		my_tramp, @function\n"
+"	.globl		my_tramp\n"
+"   my_tramp:"
+"	bti	c\n"
+"	sub	sp, sp, #32\n"
+"	stp	x9, x30, [sp]\n"
+"	str	x0, [sp, #16]\n"
+"	mov	x0, x30\n"
+"	bl	my_direct_func\n"
+"	ldp	x30, x9, [sp]\n"
+"	ldr	x0, [sp, #16]\n"
+"	add	sp, sp, #32\n"
+"	ret	x9\n"
+"	.size		my_tramp, .-my_tramp\n"
+"	.popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
 #ifdef CONFIG_LOONGARCH
 
 #include <asm/asm.h>

samples/ftrace/ftrace-direct-too.c +26 -0

index 7986033887f6..e9804c5307c0 100644
@@ -3,7 +3,9 @@
 
 #include <linux/mm.h> /* for handle_mm_fault() */
 #include <linux/ftrace.h>
+#ifndef CONFIG_ARM64
 #include <asm/asm-offsets.h>
+#endif
 
 extern void my_direct_func(struct vm_area_struct *vma, unsigned long address,
 			   unsigned int flags, struct pt_regs *regs);

@@ -72,6 +74,30 @@ asm (
 
 #endif /* CONFIG_S390 */
 
+#ifdef CONFIG_ARM64
+
+asm (
+"	.pushsection	.text, \"ax\", @progbits\n"
+"	.type		my_tramp, @function\n"
+"	.globl		my_tramp\n"
+"   my_tramp:"
+"	bti	c\n"
+"	sub	sp, sp, #48\n"
+"	stp	x9, x30, [sp]\n"
+"	stp	x0, x1, [sp, #16]\n"
+"	stp	x2, x3, [sp, #32]\n"
+"	bl	my_direct_func\n"
+"	ldp	x30, x9, [sp]\n"
+"	ldp	x0, x1, [sp, #16]\n"
+"	ldp	x2, x3, [sp, #32]\n"
+"	add	sp, sp, #48\n"
+"	ret	x9\n"
+"	.size		my_tramp, .-my_tramp\n"
+"	.popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
 #ifdef CONFIG_LOONGARCH
 
 asm (

samples/ftrace/ftrace-direct.c +24 -0

index 06879bbd3399..20f4a7caa810 100644
@@ -3,7 +3,9 @@
 
 #include <linux/sched.h> /* for wake_up_process() */
 #include <linux/ftrace.h>
+#ifndef CONFIG_ARM64
 #include <asm/asm-offsets.h>
+#endif
 
 extern void my_direct_func(struct task_struct *p);

@@ -63,6 +65,28 @@ asm (
 
 #endif /* CONFIG_S390 */
 
+#ifdef CONFIG_ARM64
+
+asm (
+"	.pushsection	.text, \"ax\", @progbits\n"
+"	.type		my_tramp, @function\n"
+"	.globl		my_tramp\n"
+"   my_tramp:"
+"	bti	c\n"
+"	sub	sp, sp, #32\n"
+"	stp	x9, x30, [sp]\n"
+"	str	x0, [sp, #16]\n"
+"	bl	my_direct_func\n"
+"	ldp	x30, x9, [sp]\n"
+"	ldr	x0, [sp, #16]\n"
+"	add	sp, sp, #32\n"
+"	ret	x9\n"
+"	.size		my_tramp, .-my_tramp\n"
+"	.popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
 #ifdef CONFIG_LOONGARCH
 
 asm (

Signature · 1 line

2.40.1

Steven Rostedt

author maintainer

2023-07-11 14:07 UTC #3 lore raw

PATCH 3/5 x86/ftrace: Remove unsued extern declaration ftrace_regs_caller_ret()

In reply to Steven Rostedt

From: YueHaibing <[email protected]>

This is now unused, so can remove it.

Link https://lore.kernel.org/linux-trace-kernel/[email protected] open here

Cc <[email protected]>

Signed-off-by YueHaibing <[email protected]>

Acked-by Masami Hiramatsu (Google) <[email protected]>

Signed-off-by Steven Rostedt (Google) <[email protected]>

---
 arch/x86/kernel/ftrace.c | 1 -
 1 file changed, 1 deletion(-)

arch/x86/kernel/ftrace.c +0 -1

index 5e7ead52cfdb..c323a6b648ab 100644
@@ -282,7 +282,6 @@ static inline void tramp_free(void *tramp) { }
 
 /* Defined as markers to the end of the ftrace default trampolines */
 extern void ftrace_regs_caller_end(void);
-extern void ftrace_regs_caller_ret(void);
 extern void ftrace_caller_end(void);
 extern void ftrace_caller_op_ptr(void);
 extern void ftrace_regs_caller_op_ptr(void);

Signature · 1 line

2.40.1

Steven Rostedt

author maintainer

2023-07-11 14:07 UTC #4 lore raw

PATCH 4/5 tracing: arm64: Avoid missing-prototype warnings

In reply to Steven Rostedt

From: Arnd Bergmann <[email protected]>

These are all tracing W=1 warnings in arm64 allmodconfig about missing prototypes:

kernel/trace/trace_kprobe_selftest.c:7:5: error: no previous prototype for 'kprobe_trace_selftest_target' [-Werror=missing-pro totypes]
kernel/trace/ftrace.c:329:5: error: no previous prototype for '__register_ftrace_function' [-Werror=missing-prototypes] kernel/trace/ftrace.c:372:5: error: no previous prototype for '__unregister_ftrace_function' [-Werror=missing-prototypes] kernel/trace/ftrace.c:4130:15: error: no previous prototype for 'arch_ftrace_match_adjust' [-Werror=missing-prototypes] kernel/trace/fgraph.c:243:15: error: no previous prototype for 'ftrace_return_to_handler' [-Werror=missing-prototypes] kernel/trace/fgraph.c:358:6: error: no previous prototype for 'ftrace_graph_sleep_time_control' [-Werror=missing-prototypes] arch/arm64/kernel/ftrace.c:460:6: error: no previous prototype for 'prepare_ftrace_return' [-Werror=missing-prototypes] arch/arm64/kernel/ptrace.c:2172:5: error: no previous prototype for 'syscall_trace_enter' [-Werror=missing-prototypes] arch/arm64/kernel/ptrace.c:2195:6: error: no previous prototype for 'syscall_trace_exit' [-Werror=missing-prototypes]

Move the declarations to an appropriate header where they can be seen by the caller and callee, and make sure the headers are included where needed.

Link https://lore.kernel.org/linux-trace-kernel/[email protected] open here

Cc Masami Hiramatsu <[email protected]>

Cc Mark Rutland <[email protected]>

Cc Will Deacon <[email protected]>

Cc Kees Cook <[email protected]>

Cc Florent Revest <[email protected]>

Signed-off-by Arnd Bergmann <[email protected]>

Acked-by Catalin Marinas <[email protected]>

[ Fixed ftrace_return_to_handler() to handle CONFIG_HAVE_FUNCTION_GRAPH_RETVAL case ]

Signed-off-by Steven Rostedt (Google) <[email protected]>

---
 arch/arm64/include/asm/ftrace.h      | 4 ++++
 arch/arm64/include/asm/syscall.h     | 3 +++
 arch/arm64/kernel/syscall.c          | 3 ---
 include/linux/ftrace.h               | 8 ++++++++
 kernel/trace/fgraph.c                | 1 +
 kernel/trace/ftrace_internal.h       | 5 +++--
 kernel/trace/trace_kprobe_selftest.c | 3 +++
 7 files changed, 22 insertions(+), 5 deletions(-)

arch/arm64/include/asm/ftrace.h +4 -0

index 21ac1c5c71d3..ab158196480c 100644
@@ -211,6 +211,10 @@ static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs
 {
 	return ret_regs->fp;
 }
+
+void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent,
+			   unsigned long frame_pointer);
+
 #endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER  */
 #endif

arch/arm64/include/asm/syscall.h +3 -0

index 4cfe9b49709b..ab8e14b96f68 100644
@@ -85,4 +85,7 @@ static inline int syscall_get_arch(struct task_struct *task)
 	return AUDIT_ARCH_AARCH64;
 }
 
+int syscall_trace_enter(struct pt_regs *regs);
+void syscall_trace_exit(struct pt_regs *regs);
+
 #endif	/* __ASM_SYSCALL_H */

arch/arm64/kernel/syscall.c +0 -3

index da84cf855c44..32f49f8f1b91 100644
@@ -75,9 +75,6 @@ static inline bool has_syscall_work(unsigned long flags)
 	return unlikely(flags & _TIF_SYSCALL_WORK);
 }
 
-int syscall_trace_enter(struct pt_regs *regs);
-void syscall_trace_exit(struct pt_regs *regs);
-
 static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr,
 			   const syscall_fn_t syscall_table[])
 {

include/linux/ftrace.h +8 -0

index 8e59bd954153..2abd20d9211d 100644
@@ -41,6 +41,14 @@ struct ftrace_ops;
 struct ftrace_regs;
 struct dyn_ftrace;
 
+char *arch_ftrace_match_adjust(char *str, const char *search);
+
+#ifdef CONFIG_HAVE_FUNCTION_GRAPH_RETVAL
+unsigned long ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs);
+#else
+unsigned long ftrace_return_to_handler(unsigned long frame_pointer);
+#endif
+
 #ifdef CONFIG_FUNCTION_TRACER
 /*
  * If the arch's mcount caller does not support all of ftrace's

kernel/trace/fgraph.c +1 -0

index cd2c35b1dd8f..c83c005e654e 100644
@@ -15,6 +15,7 @@
 #include <trace/events/sched.h>
 
 #include "ftrace_internal.h"
+#include "trace.h"
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 #define ASSIGN_OPS_HASH(opsname, val) \

kernel/trace/ftrace_internal.h +3 -2

index 382775edf690..5012c04f92c0 100644
@@ -2,6 +2,9 @@
 #ifndef _LINUX_KERNEL_FTRACE_INTERNAL_H
 #define  _LINUX_KERNEL_FTRACE_INTERNAL_H
 
+int __register_ftrace_function(struct ftrace_ops *ops);
+int __unregister_ftrace_function(struct ftrace_ops *ops);
+
 #ifdef CONFIG_FUNCTION_TRACER
 
 extern struct mutex ftrace_lock;

@@ -15,8 +18,6 @@ int ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs);
 
 #else /* !CONFIG_DYNAMIC_FTRACE */
 
-int __register_ftrace_function(struct ftrace_ops *ops);
-int __unregister_ftrace_function(struct ftrace_ops *ops);
 /* Keep as macros so we do not need to define the commands */
 # define ftrace_startup(ops, command)					\
 	({								\

kernel/trace/trace_kprobe_selftest.c +3 -0

index 16548ee4c8c6..3851cd1e6a62 100644
@@ -1,4 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
+
+#include "trace_kprobe_selftest.h"
+
 /*
  * Function used during the kprobe self test. This function is in a separate
  * compile unit so it can be compile with CC_FLAGS_FTRACE to ensure that it

Signature · 1 line

2.40.1

Steven Rostedt

author maintainer

2023-07-11 14:07 UTC #5 lore raw

PATCH 5/5 tracing/user_events: Fix struct arg size match check

In reply to Steven Rostedt

From: Beau Belgrave <[email protected]>

When users register an event the name of the event and it's argument are checked to ensure they match if the event already exists. Normally all arguments are in the form of "type name", except for when the type starts with "struct ". In those cases, the size of the struct is passed in addition to the name, IE: "struct my_struct a 20" for an argument that is of type "struct my_struct" with a field name of "a" and has the size of 20 bytes.

The current code does not honor the above case properly when comparing a match. This causes the event register to fail even when the same string was used for events that contain a struct argument within them. The example above "struct my_struct a 20" generates a match string of "struct my_struct a" omitting the size field.

Add the struct size of the existing field when generating a comparison string for a struct field to ensure proper match checking.

Link https://lkml.kernel.org/r/[email protected] open here

Cc [email protected]

Fixes e6f89a149872 ("tracing/user_events: Ensure user provided strings are safely formatted")

Signed-off-by Beau Belgrave <[email protected]>

Signed-off-by Steven Rostedt (Google) <[email protected]>

---
 kernel/trace/trace_events_user.c | 3 +++
 1 file changed, 3 insertions(+)

kernel/trace/trace_events_user.c +3 -0

index dbb14705d0d3..83c0536ff41c 100644
@@ -1223,6 +1223,9 @@ static int user_field_set_string(struct ftrace_event_field *field,
 	pos += snprintf(buf + pos, LEN_OR_ZERO, " ");
 	pos += snprintf(buf + pos, LEN_OR_ZERO, "%s", field->name);
 
+	if (str_has_prefix(field->type, "struct "))
+		pos += snprintf(buf + pos, LEN_OR_ZERO, " %d", field->size);
+
 	if (colon)
 		pos += snprintf(buf + pos, LEN_OR_ZERO, ";");

Signature · 1 line

2.40.1