From: Steven Rostedt Most function arguments that are passed in as unsigned int or unsigned long are better displayed as hexadecimal than normal integer. For example, the functions: static void __create_object(unsigned long ptr, size_t size, int min_count, gfp_t gfp, unsigned int objflags); static bool stack_access_ok(struct unwind_state *state, unsigned long _addr, size_t len); void __local_bh_disable_ip(unsigned long ip, unsigned int cnt); Show up in the trace as: __create_object(ptr=-131387050520576, size=4096, min_count=1, gfp=3264, objflags=0) <-kmem_cache_alloc_noprof stack_access_ok(state=0xffffc9000233fc98, _addr=-60473102566256, len=8) <-unwind_next_frame __local_bh_disable_ip(ip=-2127311112, cnt=256) <-handle_softirqs Instead, by displaying unsigned as hexadecimal, they look more like this: __create_object(ptr=0xffff8881028d2080, size=0x280, min_count=1, gfp=0x82820, objflags=0x0) <-kmem_cache_alloc_node_noprof stack_access_ok(state=0xffffc90000003938, _addr=0xffffc90000003930, len=0x8) <-unwind_next_frame __local_bh_disable_ip(ip=0xffffffff8133cef8, cnt=0x100) <-handle_softirqs Which is much easier to understand as most unsigned longs are usually just pointers. Even the "unsigned int cnt" in __local_bh_disable_ip() looks better as hexadecimal as a lot of flags are passed as unsigned. Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_output.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 0b3db02030a7..b18393d66a7f 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -690,6 +690,12 @@ int trace_print_lat_context(struct trace_iterator *iter) } #ifdef CONFIG_FUNCTION_TRACE_ARGS + +static u32 btf_type_int(const struct btf_type *t) +{ + return *(u32 *)(t + 1); +} + void print_function_args(struct trace_seq *s, unsigned long *args, unsigned long func) { @@ -701,6 +707,8 @@ void print_function_args(struct trace_seq *s, unsigned long *args, struct btf *btf; s32 tid, nr = 0; int a, p, x; + int int_data; + u16 encode; trace_seq_printf(s, "("); @@ -744,7 +752,14 @@ void print_function_args(struct trace_seq *s, unsigned long *args, trace_seq_printf(s, "0x%lx", arg); break; case BTF_KIND_INT: - trace_seq_printf(s, "%ld", arg); + /* Get the INT encodoing */ + int_data = btf_type_int(t); + encode = BTF_INT_ENCODING(int_data); + /* Print unsigned ints as hex */ + if (encode & BTF_INT_SIGNED) + trace_seq_printf(s, "%ld", arg); + else + trace_seq_printf(s, "0x%lx", arg); break; case BTF_KIND_ENUM: trace_seq_printf(s, "%ld", arg); -- 2.47.2