From 0f4fc29dd68dfab9c6ddd5d087d34a5b6818cb00 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 20 May 2009 19:21:47 -0400 Subject: [PATCH] tracing: add __print_symbolic to trace events This patch adds __print_symbolic which is similar to __print_flags but works for an enumeration type instead. That is, there is only a one to one mapping between the values and the symbols. When a match is made, then it is printed, otherwise the hex value is outputed. [ Impact: add interface for showing symbol names in events ] Signed-off-by: Steven Rostedt Signed-off-by: Frederic Weisbecker --- include/linux/ftrace_event.h | 3 +++ include/trace/ftrace.h | 8 ++++++++ kernel/trace/trace_output.c | 25 +++++++++++++++++++++++++ 3 files changed, 36 insertions(+) diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 4b58cf1a11c2..bbf40f624fc8 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -20,6 +20,9 @@ const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim, unsigned long flags, const struct trace_print_flags *flag_array); +const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, + const struct trace_print_flags *symbol_array); + /* * The trace entry - the most basic unit of tracing. This is what * is printed in the end as a single line in the trace output, such as: diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 22c94719c569..87fc227c6fbe 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -130,6 +130,14 @@ ftrace_print_flags_seq(p, delim, flag, flags); \ }) +#undef __print_symbolic +#define __print_symbolic(value, symbol_array...) \ + ({ \ + static const struct trace_print_flags symbols[] = \ + { symbol_array, { -1, NULL }}; \ + ftrace_print_symbols_seq(p, value, symbols); \ + }) + #undef TRACE_EVENT #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \ enum print_line_t \ diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index a4840c260c89..c12d95db2f56 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -251,6 +251,31 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim, return p->buffer; } +const char * +ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, + const struct trace_print_flags *symbol_array) +{ + int i; + + trace_seq_init(p); + + for (i = 0; symbol_array[i].name; i++) { + + if (val != symbol_array[i].mask) + continue; + + trace_seq_puts(p, symbol_array[i].name); + break; + } + + if (!p->len) + trace_seq_printf(p, "0x%lx", val); + + trace_seq_putc(p, 0); + + return p->buffer; +} + #ifdef CONFIG_KRETPROBES static inline const char *kretprobed(const char *name) { -- 2.30.2