From 3c6d8d84423932f1d9949179c6acdf2405515ee4 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Thu, 19 Dec 2013 18:17:44 +0900 Subject: [PATCH] tools lib traceevent: Add state member to struct trace_seq The trace_seq->state is for tracking errors during the use of trace_seq APIs and getting rid of die() in it. Signed-off-by: Namhyung Kim Reviewed-by: Jiri Olsa Acked-by: Steven Rostedt Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/87fvopalbb.fsf@sejong.aot.lge.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/traceevent/Makefile | 2 +- tools/lib/traceevent/event-parse.h | 7 +++++ tools/lib/traceevent/trace-seq.c | 55 +++++++++++++++++++++++++++++--------- 3 files changed, 50 insertions(+), 14 deletions(-) diff --git a/tools/lib/traceevent/Makefile b/tools/lib/traceevent/Makefile index f778d48..56d52a3 100644 --- a/tools/lib/traceevent/Makefile +++ b/tools/lib/traceevent/Makefile @@ -136,7 +136,7 @@ export Q VERBOSE EVENT_PARSE_VERSION = $(EP_VERSION).$(EP_PATCHLEVEL).$(EP_EXTRAVERSION) -INCLUDES = -I. $(CONFIG_INCLUDES) +INCLUDES = -I. -I $(srctree)/../../include $(CONFIG_INCLUDES) # Set compile option CFLAGS if not set elsewhere CFLAGS ?= -g -Wall diff --git a/tools/lib/traceevent/event-parse.h b/tools/lib/traceevent/event-parse.h index cf5db90..3c890cb 100644 --- a/tools/lib/traceevent/event-parse.h +++ b/tools/lib/traceevent/event-parse.h @@ -58,6 +58,12 @@ struct pevent_record { #endif }; +enum trace_seq_fail { + TRACE_SEQ__GOOD, + TRACE_SEQ__BUFFER_POISONED, + TRACE_SEQ__MEM_ALLOC_FAILED, +}; + /* * Trace sequences are used to allow a function to call several other functions * to create a string of data to use (up to a max of PAGE_SIZE). @@ -68,6 +74,7 @@ struct trace_seq { unsigned int buffer_size; unsigned int len; unsigned int readpos; + enum trace_seq_fail state; }; void trace_seq_init(struct trace_seq *s); diff --git a/tools/lib/traceevent/trace-seq.c b/tools/lib/traceevent/trace-seq.c index d7f2e68..f711213 100644 --- a/tools/lib/traceevent/trace-seq.c +++ b/tools/lib/traceevent/trace-seq.c @@ -22,6 +22,7 @@ #include #include +#include #include "event-parse.h" #include "event-utils.h" @@ -32,10 +33,21 @@ #define TRACE_SEQ_POISON ((void *)0xdeadbeef) #define TRACE_SEQ_CHECK(s) \ do { \ - if ((s)->buffer == TRACE_SEQ_POISON) \ - die("Usage of trace_seq after it was destroyed"); \ + if (WARN_ONCE((s)->buffer == TRACE_SEQ_POISON, \ + "Usage of trace_seq after it was destroyed")) \ + (s)->state = TRACE_SEQ__BUFFER_POISONED; \ } while (0) +#define TRACE_SEQ_CHECK_RET_N(s, n) \ +do { \ + TRACE_SEQ_CHECK(s); \ + if ((s)->state != TRACE_SEQ__GOOD) \ + return n; \ +} while (0) + +#define TRACE_SEQ_CHECK_RET(s) TRACE_SEQ_CHECK_RET_N(s, ) +#define TRACE_SEQ_CHECK_RET0(s) TRACE_SEQ_CHECK_RET_N(s, 0) + /** * trace_seq_init - initialize the trace_seq structure * @s: a pointer to the trace_seq structure to initialize @@ -46,6 +58,7 @@ void trace_seq_init(struct trace_seq *s) s->readpos = 0; s->buffer_size = TRACE_SEQ_BUF_SIZE; s->buffer = malloc_or_die(s->buffer_size); + s->state = TRACE_SEQ__GOOD; } /** @@ -71,7 +84,7 @@ void trace_seq_destroy(struct trace_seq *s) { if (!s) return; - TRACE_SEQ_CHECK(s); + TRACE_SEQ_CHECK_RET(s); free(s->buffer); s->buffer = TRACE_SEQ_POISON; } @@ -80,8 +93,9 @@ static void expand_buffer(struct trace_seq *s) { s->buffer_size += TRACE_SEQ_BUF_SIZE; s->buffer = realloc(s->buffer, s->buffer_size); - if (!s->buffer) - die("Can't allocate trace_seq buffer memory"); + if (WARN_ONCE(!s->buffer, + "Can't allocate trace_seq buffer memory")) + s->state = TRACE_SEQ__MEM_ALLOC_FAILED; } /** @@ -105,9 +119,9 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...) int len; int ret; - TRACE_SEQ_CHECK(s); - try_again: + TRACE_SEQ_CHECK_RET0(s); + len = (s->buffer_size - 1) - s->len; va_start(ap, fmt); @@ -141,9 +155,9 @@ trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args) int len; int ret; - TRACE_SEQ_CHECK(s); - try_again: + TRACE_SEQ_CHECK_RET0(s); + len = (s->buffer_size - 1) - s->len; ret = vsnprintf(s->buffer + s->len, len, fmt, args); @@ -172,13 +186,15 @@ int trace_seq_puts(struct trace_seq *s, const char *str) { int len; - TRACE_SEQ_CHECK(s); + TRACE_SEQ_CHECK_RET0(s); len = strlen(str); while (len > ((s->buffer_size - 1) - s->len)) expand_buffer(s); + TRACE_SEQ_CHECK_RET0(s); + memcpy(s->buffer + s->len, str, len); s->len += len; @@ -187,11 +203,13 @@ int trace_seq_puts(struct trace_seq *s, const char *str) int trace_seq_putc(struct trace_seq *s, unsigned char c) { - TRACE_SEQ_CHECK(s); + TRACE_SEQ_CHECK_RET0(s); while (s->len >= (s->buffer_size - 1)) expand_buffer(s); + TRACE_SEQ_CHECK_RET0(s); + s->buffer[s->len++] = c; return 1; @@ -199,7 +217,7 @@ int trace_seq_putc(struct trace_seq *s, unsigned char c) void trace_seq_terminate(struct trace_seq *s) { - TRACE_SEQ_CHECK(s); + TRACE_SEQ_CHECK_RET(s); /* There's always one character left on the buffer */ s->buffer[s->len] = 0; @@ -208,5 +226,16 @@ void trace_seq_terminate(struct trace_seq *s) int trace_seq_do_printf(struct trace_seq *s) { TRACE_SEQ_CHECK(s); - return printf("%.*s", s->len, s->buffer); + + switch (s->state) { + case TRACE_SEQ__GOOD: + return printf("%.*s", s->len, s->buffer); + case TRACE_SEQ__BUFFER_POISONED: + puts("Usage of trace_seq after it was destroyed"); + break; + case TRACE_SEQ__MEM_ALLOC_FAILED: + puts("Can't allocate trace_seq buffer memory"); + break; + } + return -1; } -- 2.7.4