| Message ID | 20240904065908.1009086-8-svens@linux.ibm.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Masami Hiramatsu |
| Headers | show |
| Series | add function arguments to ftrace | expand |
On 2024/9/4 14:59, Sven Schnelle wrote: > Wire up the code to print function arguments in the function tracer. > This functionality can be enabled/disabled during compile time by > setting CONFIG_FUNCTION_TRACE_ARGS and during runtime with > options/func-args. > > ping-689 [004] b.... 77.170220: dummy_xmit(skb = 0x82904800, dev = 0x882d0000) <-dev_hard_start_xmit > > Signed-off-by: Sven Schnelle <svens@linux.ibm.com> > --- > kernel/trace/trace.c | 8 +++++- > kernel/trace/trace.h | 4 ++- > kernel/trace/trace_entries.h | 7 +++-- > kernel/trace/trace_functions.c | 46 +++++++++++++++++++++++++++---- > kernel/trace/trace_irqsoff.c | 4 +-- > kernel/trace/trace_output.c | 14 ++++++++-- > kernel/trace/trace_sched_wakeup.c | 4 +-- > 7 files changed, 71 insertions(+), 16 deletions(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index ebe7ce2f5f4a..8118e4c8c649 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -2864,7 +2864,7 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, > > void > trace_function(struct trace_array *tr, unsigned long ip, unsigned long > - parent_ip, unsigned int trace_ctx) > + parent_ip, unsigned int trace_ctx, struct ftrace_regs *regs) > { > struct trace_event_call *call = &event_function; > struct trace_buffer *buffer = tr->array_buffer.buffer; > @@ -2878,6 +2878,12 @@ trace_function(struct trace_array *tr, unsigned long ip, unsigned long > entry = ring_buffer_event_data(event); > entry->ip = ip; > entry->parent_ip = parent_ip; > +#ifdef CONFIG_FUNCTION_TRACE_ARGS > + if (regs) > + entry->regs = *regs; > + else > + memset(&entry->regs, 0, sizeof(struct ftrace_regs)); > +#endif > > if (!call_filter_check_discard(call, entry, buffer, event)) { > if (static_branch_unlikely(&trace_function_exports_enabled)) > diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h > index bd3e3069300e..13cf6f97f7e0 100644 > --- a/kernel/trace/trace.h > +++ b/kernel/trace/trace.h > @@ -673,7 +673,8 @@ unsigned long trace_total_entries(struct trace_array *tr); > void trace_function(struct trace_array *tr, > unsigned long ip, > unsigned long parent_ip, > - unsigned int trace_ctx); > + unsigned int trace_ctx, > + struct ftrace_regs *regs); > void trace_graph_function(struct trace_array *tr, > unsigned long ip, > unsigned long parent_ip, > @@ -870,6 +871,7 @@ static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash) > #define TRACE_GRAPH_GRAPH_TIME 0x400 > #define TRACE_GRAPH_PRINT_RETVAL 0x800 > #define TRACE_GRAPH_PRINT_RETVAL_HEX 0x1000 > +#define TRACE_GRAPH_ARGS 0x2000 > #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 > #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) > > diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h > index c47422b20908..f2021ab52da2 100644 > --- a/kernel/trace/trace_entries.h > +++ b/kernel/trace/trace_entries.h > @@ -61,8 +61,11 @@ FTRACE_ENTRY_REG(function, ftrace_entry, > TRACE_FN, > > F_STRUCT( > - __field_fn( unsigned long, ip ) > - __field_fn( unsigned long, parent_ip ) > + __field_fn( unsigned long, ip ) > + __field_fn( unsigned long, parent_ip ) > +#ifdef CONFIG_FUNCTION_TRACE_ARGS > + __field_struct( struct ftrace_regs, regs ) Only function arguments are printed, they are several registers in ftrace_regs, would it be better to store what are needed? Although different archs save function arguments in different registers, store the entire ftrace_regs are much more simple.. > +#endif > ), > > F_printk(" %ps <-- %ps", F_printk should also match F_STRUCT, otherwise 'format' info may be incorrect, it may confuse data parsing in user tools. > diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c > index 3b0cea37e029..7ff651a0b45a 100644 > --- a/kernel/trace/trace_functions.c > +++ b/kernel/trace/trace_functions.c > @@ -25,6 +25,9 @@ static void > function_trace_call(unsigned long ip, unsigned long parent_ip, > struct ftrace_ops *op, struct ftrace_regs *fregs); > static void > +function_args_trace_call(unsigned long ip, unsigned long parent_ip, > + struct ftrace_ops *op, struct ftrace_regs *fregs); > +static void > function_stack_trace_call(unsigned long ip, unsigned long parent_ip, > struct ftrace_ops *op, struct ftrace_regs *fregs); > static void > @@ -42,9 +45,10 @@ enum { > TRACE_FUNC_NO_OPTS = 0x0, /* No flags set. */ > TRACE_FUNC_OPT_STACK = 0x1, > TRACE_FUNC_OPT_NO_REPEATS = 0x2, > + TRACE_FUNC_OPT_ARGS = 0x4, > > /* Update this to next highest bit. */ > - TRACE_FUNC_OPT_HIGHEST_BIT = 0x4 > + TRACE_FUNC_OPT_HIGHEST_BIT = 0x8 > }; > > #define TRACE_FUNC_OPT_MASK (TRACE_FUNC_OPT_HIGHEST_BIT - 1) > @@ -114,6 +118,8 @@ static ftrace_func_t select_trace_function(u32 flags_val) > switch (flags_val & TRACE_FUNC_OPT_MASK) { > case TRACE_FUNC_NO_OPTS: > return function_trace_call; > + case TRACE_FUNC_OPT_ARGS: > + return function_args_trace_call; > case TRACE_FUNC_OPT_STACK: > return function_stack_trace_call; > case TRACE_FUNC_OPT_NO_REPEATS: > @@ -198,7 +204,34 @@ function_trace_call(unsigned long ip, unsigned long parent_ip, > cpu = smp_processor_id(); > data = per_cpu_ptr(tr->array_buffer.data, cpu); > if (!atomic_read(&data->disabled)) > - trace_function(tr, ip, parent_ip, trace_ctx); > + trace_function(tr, ip, parent_ip, trace_ctx, NULL); > + > + ftrace_test_recursion_unlock(bit); > +} > + > +static void > +function_args_trace_call(unsigned long ip, unsigned long parent_ip, > + struct ftrace_ops *op, struct ftrace_regs *fregs) > +{ > + struct trace_array *tr = op->private; > + struct trace_array_cpu *data; > + unsigned int trace_ctx; > + int bit; > + int cpu; > + > + if (unlikely(!tr->function_enabled)) > + return; > + > + bit = ftrace_test_recursion_trylock(ip, parent_ip); > + if (bit < 0) > + return; > + > + trace_ctx = tracing_gen_ctx(); > + > + cpu = smp_processor_id(); > + data = per_cpu_ptr(tr->array_buffer.data, cpu); > + if (!atomic_read(&data->disabled)) > + trace_function(tr, ip, parent_ip, trace_ctx, fregs); > > ftrace_test_recursion_unlock(bit); > } > @@ -247,7 +280,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip, > > if (likely(disabled == 1)) { > trace_ctx = tracing_gen_ctx_flags(flags); > - trace_function(tr, ip, parent_ip, trace_ctx); > + trace_function(tr, ip, parent_ip, trace_ctx, NULL); > #ifdef CONFIG_UNWINDER_FRAME_POINTER > if (ftrace_pids_enabled(op)) > skip++; > @@ -329,7 +362,7 @@ function_no_repeats_trace_call(unsigned long ip, unsigned long parent_ip, > trace_ctx = tracing_gen_ctx_flags(flags); > process_repeats(tr, ip, parent_ip, last_info, trace_ctx); > > - trace_function(tr, ip, parent_ip, trace_ctx); > + trace_function(tr, ip, parent_ip, trace_ctx, NULL); > > out: > ftrace_test_recursion_unlock(bit); > @@ -368,7 +401,7 @@ function_stack_no_repeats_trace_call(unsigned long ip, unsigned long parent_ip, > trace_ctx = tracing_gen_ctx_flags(flags); > process_repeats(tr, ip, parent_ip, last_info, trace_ctx); > > - trace_function(tr, ip, parent_ip, trace_ctx); > + trace_function(tr, ip, parent_ip, trace_ctx, NULL); > __trace_stack(tr, trace_ctx, STACK_SKIP); > } > > @@ -382,6 +415,9 @@ static struct tracer_opt func_opts[] = { > { TRACER_OPT(func_stack_trace, TRACE_FUNC_OPT_STACK) }, > #endif > { TRACER_OPT(func-no-repeats, TRACE_FUNC_OPT_NO_REPEATS) }, > +#ifdef CONFIG_FUNCTION_TRACE_ARGS > + { TRACER_OPT(func-args, TRACE_FUNC_OPT_ARGS) }, > +#endif > { } /* Always set a last empty entry */ > }; > > diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c > index fce064e20570..096002c99d70 100644 > --- a/kernel/trace/trace_irqsoff.c > +++ b/kernel/trace/trace_irqsoff.c > @@ -150,7 +150,7 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip, > > trace_ctx = tracing_gen_ctx_flags(flags); > > - trace_function(tr, ip, parent_ip, trace_ctx); > + trace_function(tr, ip, parent_ip, trace_ctx, fregs); > > atomic_dec(&data->disabled); > } > @@ -278,7 +278,7 @@ __trace_function(struct trace_array *tr, > if (is_graph(tr)) > trace_graph_function(tr, ip, parent_ip, trace_ctx); > else > - trace_function(tr, ip, parent_ip, trace_ctx); > + trace_function(tr, ip, parent_ip, trace_ctx, NULL); > } > > #else > diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c > index 70405c4cceb6..8fdee7b9cdba 100644 > --- a/kernel/trace/trace_output.c > +++ b/kernel/trace/trace_output.c > @@ -1058,9 +1058,13 @@ enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags, > } > > static void print_fn_trace(struct trace_seq *s, unsigned long ip, > - unsigned long parent_ip, int flags) > + unsigned long parent_ip, > + struct ftrace_regs *fregs, > + int flags) > { > seq_print_ip_sym(s, ip, flags); > + if (fregs) > + print_function_args(s, fregs, ip); > > if ((flags & TRACE_ITER_PRINT_PARENT) && parent_ip) { > trace_seq_puts(s, " <-"); > @@ -1074,10 +1078,14 @@ static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags, > { > struct ftrace_entry *field; > struct trace_seq *s = &iter->seq; > + struct ftrace_regs *fregs = NULL; > > trace_assign_type(field, iter->ent); > > - print_fn_trace(s, field->ip, field->parent_ip, flags); > +#if IS_ENABLED(CONFIG_FUNCTION_TRACE_ARGS) > + fregs = &field->regs; > +#endif > + print_fn_trace(s, field->ip, field->parent_ip, fregs, flags); > trace_seq_putc(s, '\n'); > > return trace_handle_return(s); > @@ -1742,7 +1750,7 @@ trace_func_repeats_print(struct trace_iterator *iter, int flags, > > trace_assign_type(field, iter->ent); > > - print_fn_trace(s, field->ip, field->parent_ip, flags); > + print_fn_trace(s, field->ip, field->parent_ip, NULL, flags); > trace_seq_printf(s, " (repeats: %u, last_ts:", field->count); > trace_print_time(s, iter, > iter->ts - FUNC_REPEATS_GET_DELTA_TS(field)); > diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c > index 130ca7e7787e..39043c955761 100644 > --- a/kernel/trace/trace_sched_wakeup.c > +++ b/kernel/trace/trace_sched_wakeup.c > @@ -224,7 +224,7 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip, > return; > > local_irq_save(flags); > - trace_function(tr, ip, parent_ip, trace_ctx); > + trace_function(tr, ip, parent_ip, trace_ctx, fregs); > local_irq_restore(flags); > > atomic_dec(&data->disabled); > @@ -309,7 +309,7 @@ __trace_function(struct trace_array *tr, > if (is_graph(tr)) > trace_graph_function(tr, ip, parent_ip, trace_ctx); > else > - trace_function(tr, ip, parent_ip, trace_ctx); > + trace_function(tr, ip, parent_ip, trace_ctx, NULL); > } > > static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
On Fri, 6 Sep 2024 11:49:10 +0800 Zheng Yejian <zhengyejian@huaweicloud.com> wrote: > > diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h > > index c47422b20908..f2021ab52da2 100644 > > --- a/kernel/trace/trace_entries.h > > +++ b/kernel/trace/trace_entries.h > > @@ -61,8 +61,11 @@ FTRACE_ENTRY_REG(function, ftrace_entry, > > TRACE_FN, > > > > F_STRUCT( > > - __field_fn( unsigned long, ip ) > > - __field_fn( unsigned long, parent_ip ) > > + __field_fn( unsigned long, ip ) > > + __field_fn( unsigned long, parent_ip ) > > +#ifdef CONFIG_FUNCTION_TRACE_ARGS > > + __field_struct( struct ftrace_regs, regs ) > > Only function arguments are printed, they are several registers in ftrace_regs, > would it be better to store what are needed? > Although different archs save function arguments in different registers, store > the entire ftrace_regs are much more simple.. Agreed, and I stated as much in my reply to patch 6. This too will need two versions of the event. One will be function the other will be function_args. And it will only record the necessary arguments not the full ftrace_regs structure, as I plan on making that structure have "zero size". > > > +#endif > > ), > > > > F_printk(" %ps <-- %ps", > > F_printk should also match F_STRUCT, otherwise 'format' info may be incorrect, > it may confuse data parsing in user tools. Well, it will just ignore the struct part, as its not listed. -- Steve > > > diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c > > index 3b0cea37e029..7ff651a0b45a 100644 > > --- a/kernel/trace/trace_functions.c > > +++ b/kernel/trace/trace_functions.c > > @@ -25,6 +25,9 @@ static void > > function_trace_call(unsigned long ip, unsigned long parent_ip, > > struct ftrace_ops *op, struct ftrace_regs *fregs); > > static void > > +function_args_trace_call(unsigned long ip, unsigned long parent_ip, > > + struct ftrace_ops *op, struct ftrace_regs *fregs);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index ebe7ce2f5f4a..8118e4c8c649 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2864,7 +2864,7 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, void trace_function(struct trace_array *tr, unsigned long ip, unsigned long - parent_ip, unsigned int trace_ctx) + parent_ip, unsigned int trace_ctx, struct ftrace_regs *regs) { struct trace_event_call *call = &event_function; struct trace_buffer *buffer = tr->array_buffer.buffer; @@ -2878,6 +2878,12 @@ trace_function(struct trace_array *tr, unsigned long ip, unsigned long entry = ring_buffer_event_data(event); entry->ip = ip; entry->parent_ip = parent_ip; +#ifdef CONFIG_FUNCTION_TRACE_ARGS + if (regs) + entry->regs = *regs; + else + memset(&entry->regs, 0, sizeof(struct ftrace_regs)); +#endif if (!call_filter_check_discard(call, entry, buffer, event)) { if (static_branch_unlikely(&trace_function_exports_enabled)) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index bd3e3069300e..13cf6f97f7e0 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -673,7 +673,8 @@ unsigned long trace_total_entries(struct trace_array *tr); void trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, - unsigned int trace_ctx); + unsigned int trace_ctx, + struct ftrace_regs *regs); void trace_graph_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, @@ -870,6 +871,7 @@ static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash) #define TRACE_GRAPH_GRAPH_TIME 0x400 #define TRACE_GRAPH_PRINT_RETVAL 0x800 #define TRACE_GRAPH_PRINT_RETVAL_HEX 0x1000 +#define TRACE_GRAPH_ARGS 0x2000 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h index c47422b20908..f2021ab52da2 100644 --- a/kernel/trace/trace_entries.h +++ b/kernel/trace/trace_entries.h @@ -61,8 +61,11 @@ FTRACE_ENTRY_REG(function, ftrace_entry, TRACE_FN, F_STRUCT( - __field_fn( unsigned long, ip ) - __field_fn( unsigned long, parent_ip ) + __field_fn( unsigned long, ip ) + __field_fn( unsigned long, parent_ip ) +#ifdef CONFIG_FUNCTION_TRACE_ARGS + __field_struct( struct ftrace_regs, regs ) +#endif ), F_printk(" %ps <-- %ps", diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index 3b0cea37e029..7ff651a0b45a 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -25,6 +25,9 @@ static void function_trace_call(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); static void +function_args_trace_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs); +static void function_stack_trace_call(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); static void @@ -42,9 +45,10 @@ enum { TRACE_FUNC_NO_OPTS = 0x0, /* No flags set. */ TRACE_FUNC_OPT_STACK = 0x1, TRACE_FUNC_OPT_NO_REPEATS = 0x2, + TRACE_FUNC_OPT_ARGS = 0x4, /* Update this to next highest bit. */ - TRACE_FUNC_OPT_HIGHEST_BIT = 0x4 + TRACE_FUNC_OPT_HIGHEST_BIT = 0x8 }; #define TRACE_FUNC_OPT_MASK (TRACE_FUNC_OPT_HIGHEST_BIT - 1) @@ -114,6 +118,8 @@ static ftrace_func_t select_trace_function(u32 flags_val) switch (flags_val & TRACE_FUNC_OPT_MASK) { case TRACE_FUNC_NO_OPTS: return function_trace_call; + case TRACE_FUNC_OPT_ARGS: + return function_args_trace_call; case TRACE_FUNC_OPT_STACK: return function_stack_trace_call; case TRACE_FUNC_OPT_NO_REPEATS: @@ -198,7 +204,34 @@ function_trace_call(unsigned long ip, unsigned long parent_ip, cpu = smp_processor_id(); data = per_cpu_ptr(tr->array_buffer.data, cpu); if (!atomic_read(&data->disabled)) - trace_function(tr, ip, parent_ip, trace_ctx); + trace_function(tr, ip, parent_ip, trace_ctx, NULL); + + ftrace_test_recursion_unlock(bit); +} + +static void +function_args_trace_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs) +{ + struct trace_array *tr = op->private; + struct trace_array_cpu *data; + unsigned int trace_ctx; + int bit; + int cpu; + + if (unlikely(!tr->function_enabled)) + return; + + bit = ftrace_test_recursion_trylock(ip, parent_ip); + if (bit < 0) + return; + + trace_ctx = tracing_gen_ctx(); + + cpu = smp_processor_id(); + data = per_cpu_ptr(tr->array_buffer.data, cpu); + if (!atomic_read(&data->disabled)) + trace_function(tr, ip, parent_ip, trace_ctx, fregs); ftrace_test_recursion_unlock(bit); } @@ -247,7 +280,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip, if (likely(disabled == 1)) { trace_ctx = tracing_gen_ctx_flags(flags); - trace_function(tr, ip, parent_ip, trace_ctx); + trace_function(tr, ip, parent_ip, trace_ctx, NULL); #ifdef CONFIG_UNWINDER_FRAME_POINTER if (ftrace_pids_enabled(op)) skip++; @@ -329,7 +362,7 @@ function_no_repeats_trace_call(unsigned long ip, unsigned long parent_ip, trace_ctx = tracing_gen_ctx_flags(flags); process_repeats(tr, ip, parent_ip, last_info, trace_ctx); - trace_function(tr, ip, parent_ip, trace_ctx); + trace_function(tr, ip, parent_ip, trace_ctx, NULL); out: ftrace_test_recursion_unlock(bit); @@ -368,7 +401,7 @@ function_stack_no_repeats_trace_call(unsigned long ip, unsigned long parent_ip, trace_ctx = tracing_gen_ctx_flags(flags); process_repeats(tr, ip, parent_ip, last_info, trace_ctx); - trace_function(tr, ip, parent_ip, trace_ctx); + trace_function(tr, ip, parent_ip, trace_ctx, NULL); __trace_stack(tr, trace_ctx, STACK_SKIP); } @@ -382,6 +415,9 @@ static struct tracer_opt func_opts[] = { { TRACER_OPT(func_stack_trace, TRACE_FUNC_OPT_STACK) }, #endif { TRACER_OPT(func-no-repeats, TRACE_FUNC_OPT_NO_REPEATS) }, +#ifdef CONFIG_FUNCTION_TRACE_ARGS + { TRACER_OPT(func-args, TRACE_FUNC_OPT_ARGS) }, +#endif { } /* Always set a last empty entry */ }; diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index fce064e20570..096002c99d70 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -150,7 +150,7 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip, trace_ctx = tracing_gen_ctx_flags(flags); - trace_function(tr, ip, parent_ip, trace_ctx); + trace_function(tr, ip, parent_ip, trace_ctx, fregs); atomic_dec(&data->disabled); } @@ -278,7 +278,7 @@ __trace_function(struct trace_array *tr, if (is_graph(tr)) trace_graph_function(tr, ip, parent_ip, trace_ctx); else - trace_function(tr, ip, parent_ip, trace_ctx); + trace_function(tr, ip, parent_ip, trace_ctx, NULL); } #else diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 70405c4cceb6..8fdee7b9cdba 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -1058,9 +1058,13 @@ enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags, } static void print_fn_trace(struct trace_seq *s, unsigned long ip, - unsigned long parent_ip, int flags) + unsigned long parent_ip, + struct ftrace_regs *fregs, + int flags) { seq_print_ip_sym(s, ip, flags); + if (fregs) + print_function_args(s, fregs, ip); if ((flags & TRACE_ITER_PRINT_PARENT) && parent_ip) { trace_seq_puts(s, " <-"); @@ -1074,10 +1078,14 @@ static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags, { struct ftrace_entry *field; struct trace_seq *s = &iter->seq; + struct ftrace_regs *fregs = NULL; trace_assign_type(field, iter->ent); - print_fn_trace(s, field->ip, field->parent_ip, flags); +#if IS_ENABLED(CONFIG_FUNCTION_TRACE_ARGS) + fregs = &field->regs; +#endif + print_fn_trace(s, field->ip, field->parent_ip, fregs, flags); trace_seq_putc(s, '\n'); return trace_handle_return(s); @@ -1742,7 +1750,7 @@ trace_func_repeats_print(struct trace_iterator *iter, int flags, trace_assign_type(field, iter->ent); - print_fn_trace(s, field->ip, field->parent_ip, flags); + print_fn_trace(s, field->ip, field->parent_ip, NULL, flags); trace_seq_printf(s, " (repeats: %u, last_ts:", field->count); trace_print_time(s, iter, iter->ts - FUNC_REPEATS_GET_DELTA_TS(field)); diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 130ca7e7787e..39043c955761 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -224,7 +224,7 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip, return; local_irq_save(flags); - trace_function(tr, ip, parent_ip, trace_ctx); + trace_function(tr, ip, parent_ip, trace_ctx, fregs); local_irq_restore(flags); atomic_dec(&data->disabled); @@ -309,7 +309,7 @@ __trace_function(struct trace_array *tr, if (is_graph(tr)) trace_graph_function(tr, ip, parent_ip, trace_ctx); else - trace_function(tr, ip, parent_ip, trace_ctx); + trace_function(tr, ip, parent_ip, trace_ctx, NULL); } static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
Wire up the code to print function arguments in the function tracer. This functionality can be enabled/disabled during compile time by setting CONFIG_FUNCTION_TRACE_ARGS and during runtime with options/func-args. ping-689 [004] b.... 77.170220: dummy_xmit(skb = 0x82904800, dev = 0x882d0000) <-dev_hard_start_xmit Signed-off-by: Sven Schnelle <svens@linux.ibm.com> --- kernel/trace/trace.c | 8 +++++- kernel/trace/trace.h | 4 ++- kernel/trace/trace_entries.h | 7 +++-- kernel/trace/trace_functions.c | 46 +++++++++++++++++++++++++++---- kernel/trace/trace_irqsoff.c | 4 +-- kernel/trace/trace_output.c | 14 ++++++++-- kernel/trace/trace_sched_wakeup.c | 4 +-- 7 files changed, 71 insertions(+), 16 deletions(-)