[RFC 0/4] Some libtraceevent cleanups/simplifications

[RFC 0/4] Some libtraceevent cleanups/simplifications

[Arnaldo Carvalho de Melo]

Hi Steven,

	Please take a look, while looking at how to do some stuff in 'perf
test' just for parsing the /format file I ended up with this series, lemme know
if I can add your Acked-by and push via my perf/core branch.

- Arnaldo

Arnaldo Carvalho de Melo (4):
  tools lib traceevent: Use asprintf were applicable
  tools lib traceevent: Use calloc were applicable
  tools lib traceevent: Fix afterlife gotos
  tools lib traceevent: Remove some die() calls

 tools/lib/traceevent/event-parse.c |  357 ++++++++++++++++++++++--------------
 1 file changed, 223 insertions(+), 134 deletions(-)

-- 
1.7.9.2.358.g22243

[PATCH 1/4] tools lib traceevent: Use asprintf were applicable

[Arnaldo Carvalho de Melo]

From: Arnaldo Carvalho de Melo <acme@redhat.com>

Replacing the equivalent open coded malloc + sprintf bits.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-ghokwtdw2hgmmmn7oa9s03r4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/traceevent/event-parse.c |   58 +++++++++++++++++++-----------------
 1 file changed, 31 insertions(+), 27 deletions(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index 77ebeb8..278f989 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -827,9 +827,9 @@ static enum event_type __read_token(char **tok)
 	switch (type) {
 	case EVENT_NEWLINE:
 	case EVENT_DELIM:
-		*tok = malloc_or_die(2);
-		(*tok)[0] = ch;
-		(*tok)[1] = 0;
+		if (asprintf(tok, "%c", ch) < 0)
+			return EVENT_ERROR;
+
 		return type;
 
 	case EVENT_OP:
@@ -2769,10 +2769,8 @@ static int event_read_print(struct event_format *event)
 	if (type == EVENT_DQUOTE) {
 		char *cat;
 
-		cat = malloc_or_die(strlen(event->print_fmt.format) +
-				    strlen(token) + 1);
-		strcpy(cat, event->print_fmt.format);
-		strcat(cat, token);
+		if (asprintf(&cat, "%s%s", event->print_fmt.format, token) < 0)
+			goto fail;
 		free_token(token);
 		free_token(event->print_fmt.format);
 		event->print_fmt.format = NULL;
@@ -3516,6 +3514,18 @@ process_defined_func(struct trace_seq *s, void *data, int size,
 	return ret;
 }
 
+static void free_args(struct print_arg *args)
+{
+	struct print_arg *next;
+
+	while (args) {
+		next = args->next;
+
+		free_arg(args);
+		args = next;
+	}
+}
+
 static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struct event_format *event)
 {
 	struct pevent *pevent = event->pevent;
@@ -3551,8 +3561,9 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 	next = &arg->next;
 
 	arg->type = PRINT_ATOM;
-	arg->atom.atom = malloc_or_die(32);
-	sprintf(arg->atom.atom, "%lld", ip);
+		
+	if (asprintf(&arg->atom.atom, "%lld", ip) < 0)
+		goto out_free;
 
 	/* skip the first "%pf : " */
 	for (ptr = fmt + 6, bptr = data + field->offset;
@@ -3609,8 +3620,10 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 				arg = alloc_arg();
 				arg->next = NULL;
 				arg->type = PRINT_ATOM;
-				arg->atom.atom = malloc_or_die(32);
-				sprintf(arg->atom.atom, "%lld", val);
+				if (asprintf(&arg->atom.atom, "%lld", val) < 0) {
+					free(arg);
+					goto out_free;
+				}
 				*next = arg;
 				next = &arg->next;
 				/*
@@ -3638,18 +3651,10 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 	}
 
 	return args;
-}
-
-static void free_args(struct print_arg *args)
-{
-	struct print_arg *next;
-
-	while (args) {
-		next = args->next;
 
-		free_arg(args);
-		args = next;
-	}
+out_free:
+	free_args(args);
+	return NULL;
 }
 
 static char *
@@ -3676,9 +3681,8 @@ get_bprint_format(void *data, int size __maybe_unused,
 
 	printk = find_printk(pevent, addr);
 	if (!printk) {
-		format = malloc_or_die(45);
-		sprintf(format, "%%pf : (NO FORMAT FOUND at %llx)\n",
-			addr);
+		if (asprintf(&format, "%%pf : (NO FORMAT FOUND at %llx)\n", addr) < 0)
+			return NULL;
 		return format;
 	}
 
@@ -3686,8 +3690,8 @@ get_bprint_format(void *data, int size __maybe_unused,
 	/* Remove any quotes. */
 	if (*p == '"')
 		p++;
-	format = malloc_or_die(strlen(p) + 10);
-	sprintf(format, "%s : %s", "%pf", p);
+	if (asprintf(&format, "%s : %s", "%pf", p) < 0)
+		return NULL;
 	/* remove ending quotes and new line since we will add one too */
 	p = format + strlen(format) - 1;
 	if (*p == '"')
-- 
1.7.9.2.358.g22243

[PATCH 2/4] tools lib traceevent: Use calloc were applicable

[Arnaldo Carvalho de Melo]

From: Arnaldo Carvalho de Melo <acme@redhat.com>

Replacing the equivalent open coded malloc + memset bits.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-598fjtjbzal4wxh7fp0yv0q1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/traceevent/event-parse.c |   44 ++++++++++++------------------------
 1 file changed, 14 insertions(+), 30 deletions(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index 278f989..5e38d2f 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -117,14 +117,7 @@ void breakpoint(void)
 
 struct print_arg *alloc_arg(void)
 {
-	struct print_arg *arg;
-
-	arg = malloc_or_die(sizeof(*arg));
-	if (!arg)
-		return NULL;
-	memset(arg, 0, sizeof(*arg));
-
-	return arg;
+	return calloc(1, sizeof(struct print_arg));
 }
 
 struct cmdline {
@@ -619,14 +612,7 @@ void pevent_print_printk(struct pevent *pevent)
 
 static struct event_format *alloc_event(void)
 {
-	struct event_format *event;
-
-	event = malloc(sizeof(*event));
-	if (!event)
-		return NULL;
-	memset(event, 0, sizeof(*event));
-
-	return event;
+	return calloc(1, sizeof(struct event_format));
 }
 
 static void add_event(struct pevent *pevent, struct event_format *event)
@@ -1240,8 +1226,10 @@ static int event_read_fields(struct event_format *event, struct format_field **f
 
 		last_token = token;
 
-		field = malloc_or_die(sizeof(*field));
-		memset(field, 0, sizeof(*field));
+		field = calloc(1, sizeof(*field));
+		if (!field)
+			goto fail;
+
 		field->event = event;
 
 		/* read the rest of the type */
@@ -2179,8 +2167,9 @@ process_fields(struct event_format *event, struct print_flag_sym **list, char **
 		if (test_type_token(type, token, EVENT_DELIM, ","))
 			goto out_free;
 
-		field = malloc_or_die(sizeof(*field));
-		memset(field, 0, sizeof(*field));
+		field = calloc(1, sizeof(*field));
+		if (!field)
+			goto out_free;
 
 		value = arg_eval(arg);
 		if (value == NULL)
@@ -5098,12 +5087,11 @@ int pevent_register_print_function(struct pevent *pevent,
 		remove_func_handler(pevent, name);
 	}
 
-	func_handle = malloc(sizeof(*func_handle));
+	func_handle = calloc(1, sizeof(*func_handle));
 	if (!func_handle) {
 		do_warning("Failed to allocate function handler");
 		return PEVENT_ERRNO__MEM_ALLOC_FAILED;
 	}
-	memset(func_handle, 0, sizeof(*func_handle));
 
 	func_handle->ret_type = ret_type;
 	func_handle->name = strdup(name);
@@ -5202,13 +5190,12 @@ int pevent_register_event_handler(struct pevent *pevent,
 
  not_found:
 	/* Save for later use. */
-	handle = malloc(sizeof(*handle));
+	handle = calloc(1, sizeof(*handle));
 	if (!handle) {
 		do_warning("Failed to allocate event handler");
 		return PEVENT_ERRNO__MEM_ALLOC_FAILED;
 	}
 
-	memset(handle, 0, sizeof(*handle));
 	handle->id = id;
 	if (event_name)
 		handle->event_name = strdup(event_name);
@@ -5237,13 +5224,10 @@ int pevent_register_event_handler(struct pevent *pevent,
  */
 struct pevent *pevent_alloc(void)
 {
-	struct pevent *pevent;
+	struct pevent *pevent = calloc(1, sizeof(*pevent));
 
-	pevent = malloc(sizeof(*pevent));
-	if (!pevent)
-		return NULL;
-	memset(pevent, 0, sizeof(*pevent));
-	pevent->ref_count = 1;
+	if (pevent)
+		pevent->ref_count = 1;
 
 	return pevent;
 }
-- 
1.7.9.2.358.g22243

[PATCH 3/4] tools lib traceevent: Fix afterlife gotos

[Arnaldo Carvalho de Melo]

From: Arnaldo Carvalho de Melo <acme@redhat.com>

Instead of dying, just use do_warning and let the goto that is there to
take place.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-aoaus46ngnt9oc2pt7ckot5d@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/traceevent/event-parse.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index 5e38d2f..ecc9a17 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -1270,7 +1270,7 @@ static int event_read_fields(struct event_format *event, struct format_field **f
 		}
 
 		if (!field->type) {
-			die("no type found");
+			do_warning("%s: no type found", __func__);
 			goto fail;
 		}
 		field->name = last_token;
@@ -1317,7 +1317,7 @@ static int event_read_fields(struct event_format *event, struct format_field **f
 				free_token(token);
 				type = read_token(&token);
 				if (type == EVENT_NONE) {
-					die("failed to find token");
+					do_warning("failed to find token");
 					goto fail;
 				}
 			}
@@ -1670,7 +1670,7 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 	if (arg->type == PRINT_OP && !arg->op.left) {
 		/* handle single op */
 		if (token[1]) {
-			die("bad op token %s", token);
+			do_warning("bad op token %s", token);
 			goto out_free;
 		}
 		switch (token[0]) {
-- 
1.7.9.2.358.g22243

[PATCH 4/4] tools lib traceevent: Remove some die() calls

[Arnaldo Carvalho de Melo]

From: Arnaldo Carvalho de Melo <acme@redhat.com>

Cleaned event-parse.c this time, just propagate the errors and in handle
them the call sites.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-9ebpr2vgfk2qs2841i99sa8y@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/traceevent/event-parse.c |  249 +++++++++++++++++++++++++-----------
 1 file changed, 175 insertions(+), 74 deletions(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index ecc9a17..e8e0fe0 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -31,6 +31,7 @@
 #include <ctype.h>
 #include <errno.h>
 #include <stdint.h>
+#include <limits.h>
 
 #include "event-parse.h"
 #include "event-utils.h"
@@ -151,7 +152,9 @@ static int cmdline_init(struct pevent *pevent)
 	struct cmdline *cmdlines;
 	int i;
 
-	cmdlines = malloc_or_die(sizeof(*cmdlines) * pevent->cmdline_count);
+	cmdlines = malloc(sizeof(*cmdlines) * pevent->cmdline_count);
+	if (!cmdlines)
+		return -1;
 
 	i = 0;
 	while (cmdlist) {
@@ -179,8 +182,8 @@ static char *find_cmdline(struct pevent *pevent, int pid)
 	if (!pid)
 		return "<idle>";
 
-	if (!pevent->cmdlines)
-		cmdline_init(pevent);
+	if (!pevent->cmdlines && cmdline_init(pevent))
+		return "<not enough memory for cmdlines!>";
 
 	key.pid = pid;
 
@@ -208,8 +211,8 @@ int pevent_pid_is_registered(struct pevent *pevent, int pid)
 	if (!pid)
 		return 1;
 
-	if (!pevent->cmdlines)
-		cmdline_init(pevent);
+	if (!pevent->cmdlines && cmdline_init(pevent))
+		return 0;
 
 	key.pid = pid;
 
@@ -251,10 +254,14 @@ static int add_new_comm(struct pevent *pevent, const char *comm, int pid)
 		return -1;
 	}
 
-	cmdlines[pevent->cmdline_count].pid = pid;
 	cmdlines[pevent->cmdline_count].comm = strdup(comm);
-	if (!cmdlines[pevent->cmdline_count].comm)
-		die("malloc comm");
+	if (!cmdlines[pevent->cmdline_count].comm) {
+		free(cmdlines);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	cmdlines[pevent->cmdline_count].pid = pid;
 		
 	if (cmdlines[pevent->cmdline_count].comm)
 		pevent->cmdline_count++;
@@ -281,10 +288,15 @@ int pevent_register_comm(struct pevent *pevent, const char *comm, int pid)
 	if (pevent->cmdlines)
 		return add_new_comm(pevent, comm, pid);
 
-	item = malloc_or_die(sizeof(*item));
+	item = malloc(sizeof(*item));
+	if (!item)
+		return -1;
+
 	item->comm = strdup(comm);
-	if (!item->comm)
-		die("malloc comm");
+	if (!item->comm) {
+		free(item);
+		return -1;
+	}
 	item->pid = pid;
 	item->next = pevent->cmdlist;
 
@@ -348,7 +360,10 @@ static int func_map_init(struct pevent *pevent)
 	struct func_map *func_map;
 	int i;
 
-	func_map = malloc_or_die(sizeof(*func_map) * (pevent->func_count + 1));
+	func_map = malloc(sizeof(*func_map) * (pevent->func_count + 1));
+	if (!func_map)
+		return -1;
+
 	funclist = pevent->funclist;
 
 	i = 0;
@@ -448,25 +463,36 @@ pevent_find_function_address(struct pevent *pevent, unsigned long long addr)
 int pevent_register_function(struct pevent *pevent, char *func,
 			     unsigned long long addr, char *mod)
 {
-	struct func_list *item;
+	struct func_list *item = malloc(sizeof(*item));
 
-	item = malloc_or_die(sizeof(*item));
+	if (!item)
+		return -1;
 
 	item->next = pevent->funclist;
 	item->func = strdup(func);
-	if (mod)
+	if (!item->func)
+		goto out_free;
+
+	if (mod) {
 		item->mod = strdup(mod);
-	else
+		if (!item->mod)
+			goto out_free_func;
+	} else
 		item->mod = NULL;
 	item->addr = addr;
 
-	if (!item->func || (mod && !item->mod))
-		die("malloc func");
-
 	pevent->funclist = item;
 	pevent->func_count++;
 
 	return 0;
+
+out_free_func:
+	free(item->func);
+	item->func = NULL;
+out_free:
+	free(item);
+	errno = ENOMEM;
+	return -1;
 }
 
 /**
@@ -517,14 +543,16 @@ static int printk_cmp(const void *a, const void *b)
 	return 0;
 }
 
-static void printk_map_init(struct pevent *pevent)
+static int printk_map_init(struct pevent *pevent)
 {
 	struct printk_list *printklist;
 	struct printk_list *item;
 	struct printk_map *printk_map;
 	int i;
 
-	printk_map = malloc_or_die(sizeof(*printk_map) * (pevent->printk_count + 1));
+	printk_map = malloc(sizeof(*printk_map) * (pevent->printk_count + 1));
+	if (!printk_map)
+		return -1;
 
 	printklist = pevent->printklist;
 
@@ -542,6 +570,8 @@ static void printk_map_init(struct pevent *pevent)
 
 	pevent->printk_map = printk_map;
 	pevent->printklist = NULL;
+
+	return 0;
 }
 
 static struct printk_map *
@@ -550,8 +580,8 @@ find_printk(struct pevent *pevent, unsigned long long addr)
 	struct printk_map *printk;
 	struct printk_map key;
 
-	if (!pevent->printk_map)
-		printk_map_init(pevent);
+	if (!pevent->printk_map && printk_map_init(pevent))
+		return NULL;
 
 	key.addr = addr;
 
@@ -573,21 +603,27 @@ find_printk(struct pevent *pevent, unsigned long long addr)
 int pevent_register_print_string(struct pevent *pevent, char *fmt,
 				 unsigned long long addr)
 {
-	struct printk_list *item;
+	struct printk_list *item = malloc(sizeof(*item));
 
-	item = malloc_or_die(sizeof(*item));
+	if (!item)
+		return -1;
 
 	item->next = pevent->printklist;
-	item->printk = strdup(fmt);
 	item->addr = addr;
 
+	item->printk = strdup(fmt);
 	if (!item->printk)
-		die("malloc fmt");
+		goto out_free;
 
 	pevent->printklist = item;
 	pevent->printk_count++;
 
 	return 0;
+
+out_free:
+	free(item);
+	errno = ENOMEM;
+	return -1;
 }
 
 /**
@@ -615,14 +651,15 @@ static struct event_format *alloc_event(void)
 	return calloc(1, sizeof(struct event_format));
 }
 
-static void add_event(struct pevent *pevent, struct event_format *event)
+static int add_event(struct pevent *pevent, struct event_format *event)
 {
 	int i;
+	struct event_format **events = realloc(pevent->events, sizeof(event) *
+					       (pevent->nr_events + 1));
+	if (!events)
+		return -1;
 
-	pevent->events = realloc(pevent->events, sizeof(event) *
-				 (pevent->nr_events + 1));
-	if (!pevent->events)
-		die("Can not allocate events");
+	pevent->events = events;
 
 	for (i = 0; i < pevent->nr_events; i++) {
 		if (pevent->events[i]->id > event->id)
@@ -637,6 +674,8 @@ static void add_event(struct pevent *pevent, struct event_format *event)
 	pevent->nr_events++;
 
 	event->pevent = pevent;
+
+	return 0;
 }
 
 static int event_item_type(enum event_type type)
@@ -1750,8 +1789,10 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		    type == EVENT_DELIM && (strcmp(token, ")") == 0)) {
 			char *new_atom;
 
-			if (left->type != PRINT_ATOM)
-				die("bad pointer type");
+			if (left->type != PRINT_ATOM) {
+				do_warning("bad pointer type");
+				goto out_free;
+			}
 			new_atom = realloc(left->atom.atom,
 					    strlen(left->atom.atom) + 3);
 			if (!new_atom)
@@ -1868,7 +1909,11 @@ eval_type_str(unsigned long long val, const char *type, int pointer)
 			return val;
 		}
 
-		ref = malloc_or_die(len);
+		ref = malloc(len);
+		if (!ref) {
+			do_warning("%s: not enough memory!", __func__);
+			return val;
+		}
 		memcpy(ref, type, len);
 
 		/* chop off the " *" */
@@ -1945,8 +1990,10 @@ eval_type_str(unsigned long long val, const char *type, int pointer)
 static unsigned long long
 eval_type(unsigned long long val, struct print_arg *arg, int pointer)
 {
-	if (arg->type != PRINT_TYPE)
-		die("expected type argument");
+	if (arg->type != PRINT_TYPE) {
+		do_warning("expected type argument");
+		return 0;
+	}
 
 	return eval_type_str(val, arg->typecast.type, pointer);
 }
@@ -2131,7 +2178,7 @@ static char *arg_eval (struct print_arg *arg)
 	case PRINT_STRING:
 	case PRINT_BSTRING:
 	default:
-		die("invalid eval type %d", arg->type);
+		do_warning("invalid eval type %d", arg->type);
 		break;
 	}
 
@@ -2423,8 +2470,10 @@ process_paren(struct event_format *event, struct print_arg *arg, char **tok)
 		/* make this a typecast and contine */
 
 		/* prevous must be an atom */
-		if (arg->type != PRINT_ATOM)
-			die("previous needed to be PRINT_ATOM");
+		if (arg->type != PRINT_ATOM) {
+			do_warning("previous needed to be PRINT_ATOM");
+			goto out_free;
+		}
 
 		item_arg = alloc_arg();
 
@@ -2666,7 +2715,8 @@ process_arg_token(struct event_format *event, struct print_arg *arg,
 
 	case EVENT_ERROR ... EVENT_NEWLINE:
 	default:
-		die("unexpected type %d", type);
+		do_warning("unexpected type %d", type);
+		return EVENT_ERROR;
 	}
 	*tok = token;
 
@@ -2913,8 +2963,10 @@ static int get_common_info(struct pevent *pevent,
 	 * All events should have the same common elements.
 	 * Pick any event to find where the type is;
 	 */
-	if (!pevent->events)
-		die("no event_list!");
+	if (!pevent->events) {
+		do_warning("no event_list!");
+		return -1;
+	}
 
 	event = pevent->events[0];
 	field = pevent_find_common_field(event, type);
@@ -3072,7 +3124,8 @@ eval_num_arg(void *data, int size, struct event_format *event, struct print_arg
 		if (!arg->field.field) {
 			arg->field.field = pevent_find_any_field(event, arg->field.name);
 			if (!arg->field.field)
-				die("field %s not found", arg->field.name);
+				goto out_warning_field;
+			
 		}
 		/* must be a number */
 		val = pevent_read_number(pevent, data + arg->field.field->offset,
@@ -3133,8 +3186,10 @@ eval_num_arg(void *data, int size, struct event_format *event, struct print_arg
 				if (!larg->field.field) {
 					larg->field.field =
 						pevent_find_any_field(event, larg->field.name);
-					if (!larg->field.field)
-						die("field %s not found", larg->field.name);
+					if (!larg->field.field) {
+						arg = larg;
+						goto out_warning_field;
+					}
 				}
 				field_size = larg->field.field->elementsize;
 				offset = larg->field.field->offset +
@@ -3170,7 +3225,7 @@ eval_num_arg(void *data, int size, struct event_format *event, struct print_arg
 				val = left != right;
 				break;
 			default:
-				die("unknown op '%s'", arg->op.op);
+				goto out_warning_op;
 			}
 			break;
 		case '~':
@@ -3200,7 +3255,7 @@ eval_num_arg(void *data, int size, struct event_format *event, struct print_arg
 				val = left <= right;
 				break;
 			default:
-				die("unknown op '%s'", arg->op.op);
+				goto out_warning_op;
 			}
 			break;
 		case '>':
@@ -3215,12 +3270,13 @@ eval_num_arg(void *data, int size, struct event_format *event, struct print_arg
 				val = left >= right;
 				break;
 			default:
-				die("unknown op '%s'", arg->op.op);
+				goto out_warning_op;
 			}
 			break;
 		case '=':
 			if (arg->op.op[1] != '=')
-				die("unknown op '%s'", arg->op.op);
+				goto out_warning_op;
+
 			val = left == right;
 			break;
 		case '-':
@@ -3236,13 +3292,21 @@ eval_num_arg(void *data, int size, struct event_format *event, struct print_arg
 			val = left * right;
 			break;
 		default:
-			die("unknown op '%s'", arg->op.op);
+			goto out_warning_op;
 		}
 		break;
 	default: /* not sure what to do there */
 		return 0;
 	}
 	return val;
+
+out_warning_op:
+	do_warning("%s: unknown op '%s'", __func__, arg->op.op);
+	return 0;
+
+out_warning_field:
+	do_warning("%s: field %s not found", __func__, arg->field.name);
+	return 0;
 }
 
 struct flag {
@@ -3319,8 +3383,10 @@ static void print_str_arg(struct trace_seq *s, void *data, int size,
 		field = arg->field.field;
 		if (!field) {
 			field = pevent_find_any_field(event, arg->field.name);
-			if (!field)
-				die("field %s not found", arg->field.name);
+			if (!field) {
+				str = arg->field.name;
+				goto out_warning_field;
+			}
 			arg->field.field = field;
 		}
 		/* Zero sized fields, mean the rest of the data */
@@ -3337,7 +3403,11 @@ static void print_str_arg(struct trace_seq *s, void *data, int size,
 			trace_seq_printf(s, "%lx", addr);
 			break;
 		}
-		str = malloc_or_die(len + 1);
+		str = malloc(len + 1);
+		if (!str) {
+			do_warning("%s: not enough memory!", __func__);
+			return;
+		}
 		memcpy(str, data + field->offset, len);
 		str[len] = 0;
 		print_str_to_seq(s, format, len_arg, str);
@@ -3377,7 +3447,7 @@ static void print_str_arg(struct trace_seq *s, void *data, int size,
 			str = arg->hex.field->field.name;
 			field = pevent_find_any_field(event, str);
 			if (!field)
-				die("field %s not found", str);
+				goto out_warning_field;
 			arg->hex.field->field.field = field;
 		}
 		hex = data + field->offset;
@@ -3429,6 +3499,11 @@ static void print_str_arg(struct trace_seq *s, void *data, int size,
 		/* well... */
 		break;
 	}
+
+	return;
+
+out_warning_field:
+	do_warning("%s: field %s not found", __func__, arg->field.name);
 }
 
 static unsigned long long
@@ -3455,7 +3530,11 @@ process_defined_func(struct trace_seq *s, void *data, int size,
 	farg = arg->func.args;
 	param = func_handle->params;
 
-	args = malloc_or_die(sizeof(*args) * func_handle->nr_args);
+	ret = ULLONG_MAX;
+	args = malloc(sizeof(*args) * func_handle->nr_args);
+	if (!args)
+		goto out;
+
 	for (i = 0; i < func_handle->nr_args; i++) {
 		switch (param->type) {
 		case PEVENT_FUNC_ARG_INT:
@@ -3467,12 +3546,18 @@ process_defined_func(struct trace_seq *s, void *data, int size,
 			trace_seq_init(&str);
 			print_str_arg(&str, data, size, event, "%s", -1, farg);
 			trace_seq_terminate(&str);
-			string = malloc_or_die(sizeof(*string));
+			string = malloc(sizeof(*string));
+			if (!string) {
+				do_warning("%s(%d): malloc str", __func__, __LINE__);
+				goto out_free;
+			}
 			string->next = strings;
 			string->str = strdup(str.buffer);
-			if (!string->str)
-				die("malloc str");
-
+			if (!string->str) {
+				free(string);
+				do_warning("%s(%d): malloc str", __func__, __LINE__);
+				goto out_free;
+			}
 			args[i] = (uintptr_t)string->str;
 			strings = string;
 			trace_seq_destroy(&str);
@@ -3482,14 +3567,15 @@ process_defined_func(struct trace_seq *s, void *data, int size,
 			 * Something went totally wrong, this is not
 			 * an input error, something in this code broke.
 			 */
-			die("Unexpected end of arguments\n");
-			break;
+			do_warning("Unexpected end of arguments\n");
+			goto out_free;
 		}
 		farg = farg->next;
 		param = param->next;
 	}
 
 	ret = (*func_handle->func)(s, args);
+out_free:
 	free(args);
 	while (strings) {
 		string = strings;
@@ -3530,11 +3616,15 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 
 	if (!field) {
 		field = pevent_find_field(event, "buf");
-		if (!field)
-			die("can't find buffer field for binary printk");
+		if (!field) {
+			do_warning("can't find buffer field for binary printk");
+			return NULL;
+		}
 		ip_field = pevent_find_field(event, "ip");
-		if (!ip_field)
-			die("can't find ip field for binary printk");
+		if (!ip_field) {
+			do_warning("can't find ip field for binary printk");
+			return NULL;
+		}
 		pevent->bprint_buf_field = field;
 		pevent->bprint_ip_field = ip_field;
 	}
@@ -3629,7 +3719,7 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 				arg->type = PRINT_BSTRING;
 				arg->string.string = strdup(bptr);
 				if (!arg->string.string)
-					break;
+					goto out_free;
 				bptr += strlen(bptr) + 1;
 				*next = arg;
 				next = &arg->next;
@@ -3661,8 +3751,10 @@ get_bprint_format(void *data, int size __maybe_unused,
 
 	if (!field) {
 		field = pevent_find_field(event, "fmt");
-		if (!field)
-			die("can't find format field for binary printk");
+		if (!field) {
+			do_warning("can't find format field for binary printk");
+			return NULL;
+		}
 		pevent->bprint_fmt_field = field;
 	}
 
@@ -3715,8 +3807,11 @@ static void print_mac_arg(struct trace_seq *s, int mac, void *data, int size,
 	if (!arg->field.field) {
 		arg->field.field =
 			pevent_find_any_field(event, arg->field.name);
-		if (!arg->field.field)
-			die("field %s not found", arg->field.name);
+		if (!arg->field.field) {
+			do_warning("%s: field %s not found",
+				   __func__, arg->field.name);
+			return;
+		}
 	}
 	if (arg->field.field->size != 6) {
 		trace_seq_printf(s, "INVALIDMAC");
@@ -4372,7 +4467,10 @@ get_event_fields(const char *type, const char *name,
 	struct format_field *field;
 	int i = 0;
 
-	fields = malloc_or_die(sizeof(*fields) * (count + 1));
+	fields = malloc(sizeof(*fields) * (count + 1));
+	if (!fields)
+		return NULL;
+
 	for (field = list; field; field = field->next) {
 		fields[i++] = field;
 		if (i == count + 1) {
@@ -4767,7 +4865,8 @@ enum pevent_errno pevent_parse_event(struct pevent *pevent, const char *buf,
 	}
 	show_warning = 1;
 
-	add_event(pevent, event);
+	if (add_event(pevent, event))
+		goto event_alloc_failed;
 
 	if (!ret && (event->flags & EVENT_FL_ISFTRACE)) {
 		struct format_field *field;
@@ -4800,7 +4899,9 @@ enum pevent_errno pevent_parse_event(struct pevent *pevent, const char *buf,
  event_parse_failed:
 	event->flags |= EVENT_FL_FAILED;
 	/* still add it even if it failed */
-	add_event(pevent, event);
+	if (add_event(pevent, event))
+		goto event_alloc_failed;
+
 	return ret;
 
  event_alloc_failed:
-- 
1.7.9.2.358.g22243

Re: [PATCH 2/4] tools lib traceevent: Use calloc were applicable

[Namhyung Kim]

On Mon, 17 Sep 2012 17:50:47 -0300, Arnaldo Carvalho de Melo wrote:
> From: Arnaldo Carvalho de Melo <acme@redhat.com>
>
> Replacing the equivalent open coded malloc + memset bits.
>
> Cc: David Ahern <dsahern@gmail.com>
> Cc: Frederic Weisbecker <fweisbec@gmail.com>
> Cc: Jiri Olsa <jolsa@redhat.com>
> Cc: Mike Galbraith <efault@gmx.de>
> Cc: Namhyung Kim <namhyung@gmail.com>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Stephane Eranian <eranian@google.com>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Link: http://lkml.kernel.org/n/tip-598fjtjbzal4wxh7fp0yv0q1@git.kernel.org
> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> ---
>  tools/lib/traceevent/event-parse.c |   44 ++++++++++++------------------------
>  1 file changed, 14 insertions(+), 30 deletions(-)
>
> diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
> index 278f989..5e38d2f 100644
> --- a/tools/lib/traceevent/event-parse.c
> +++ b/tools/lib/traceevent/event-parse.c
> @@ -117,14 +117,7 @@ void breakpoint(void)
>  
>  struct print_arg *alloc_arg(void)
>  {
> -	struct print_arg *arg;
> -
> -	arg = malloc_or_die(sizeof(*arg));
> -	if (!arg)
> -		return NULL;
> -	memset(arg, 0, sizeof(*arg));
> -
> -	return arg;
> +	return calloc(1, sizeof(struct print_arg));
>  }

This requires every callsite of the function should handle allocation
failure.

Thanks,
Namhyung

[PATCH] tools lib traceevent: Handle alloc_arg failure

[Namhyung Kim]

From: Namhyung Kim <namhyung.kim@lge.com>

Now alloc_arg returns NULL if memory allocation failed, it should be
handled on callsites properly.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/lib/traceevent/event-parse.c | 98 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index e8e0fe0443a4..ee4fa1912542 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -1565,6 +1565,14 @@ process_cond(struct event_format *event, struct print_arg *top, char **tok)
 	left = alloc_arg();
 	right = alloc_arg();
 
+	if (!arg || !left || !right) {
+		do_warning("%s: not enough memory!", __func__);
+		/* arg will be freed at out_free */
+		free_arg(left);
+		free_arg(right);
+		goto out_free;
+	}
+
 	arg->type = PRINT_OP;
 	arg->op.left = left;
 	arg->op.right = right;
@@ -1607,6 +1615,12 @@ process_array(struct event_format *event, struct print_arg *top, char **tok)
 	char *token = NULL;
 
 	arg = alloc_arg();
+	if (!arg) {
+		do_warning("%s: not enough memory!", __func__);
+		/* '*tok' is set to top->op.op.  No need to free. */
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
 
 	*tok = NULL;
 	type = process_arg(event, arg, &token);
@@ -1726,10 +1740,18 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 
 		/* make an empty left */
 		left = alloc_arg();
+		if (!left) {
+			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+			goto out_free;
+		}
 		left->type = PRINT_NULL;
 		arg->op.left = left;
 
 		right = alloc_arg();
+		if (!right) {
+			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+			goto out_free;
+		}
 		arg->op.right = right;
 
 		/* do not free the token, it belongs to an op */
@@ -1739,6 +1761,10 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 	} else if (strcmp(token, "?") == 0) {
 
 		left = alloc_arg();
+		if (!left) {
+			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+			goto out_free;
+		}
 		/* copy the top arg to the left */
 		*left = *arg;
 
@@ -1766,6 +1792,10 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		   strcmp(token, "!=") == 0) {
 
 		left = alloc_arg();
+		if (!left) {
+			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+			goto out_free;
+		}
 
 		/* copy the top arg to the left */
 		*left = *arg;
@@ -1808,12 +1838,20 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		}
 
 		right = alloc_arg();
+		if (!right) {
+			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+			goto out_free;
+		}
 		type = process_arg_token(event, right, tok, type);
 		arg->op.right = right;
 
 	} else if (strcmp(token, "[") == 0) {
 
 		left = alloc_arg();
+		if (!left) {
+			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+			goto out_free;
+		}
 		*left = *arg;
 
 		arg->type = PRINT_OP;
@@ -2201,6 +2239,8 @@ process_fields(struct event_format *event, struct print_flag_sym **list, char **
 			break;
 
 		arg = alloc_arg();
+		if (!arg)
+			goto out_free;
 
 		free_token(token);
 		type = process_arg(event, arg, &token);
@@ -2227,6 +2267,8 @@ process_fields(struct event_format *event, struct print_flag_sym **list, char **
 
 		free_arg(arg);
 		arg = alloc_arg();
+		if (!arg)
+			goto out_free;
 
 		free_token(token);
 		type = process_arg(event, arg, &token);
@@ -2271,6 +2313,10 @@ process_flags(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_FLAGS;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
 
 	type = process_arg(event, field, &token);
 
@@ -2318,6 +2364,10 @@ process_symbols(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_SYMBOL;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
 
 	type = process_arg(event, field, &token);
 	if (test_type_token(type, token, EVENT_DELIM, ","))
@@ -2350,6 +2400,11 @@ process_hex(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_HEX;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
+
 	type = process_arg(event, field, &token);
 
 	if (test_type_token(type, token, EVENT_DELIM, ","))
@@ -2360,6 +2415,12 @@ process_hex(struct event_format *event, struct print_arg *arg, char **tok)
 	free_token(token);
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
+
 	type = process_arg(event, field, &token);
 
 	if (test_type_token(type, token, EVENT_DELIM, ")"))
@@ -2417,6 +2478,12 @@ process_dynamic_array(struct event_format *event, struct print_arg *arg, char **
 
 	free_token(token);
 	arg = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
+
 	type = process_arg(event, arg, &token);
 	if (type == EVENT_ERROR)
 		goto out_free_arg;
@@ -2476,6 +2543,10 @@ process_paren(struct event_format *event, struct print_arg *arg, char **tok)
 		}
 
 		item_arg = alloc_arg();
+		if (!item_arg) {
+			do_warning("%s: not enough memory!", __func__);
+			goto out_free;
+		}
 
 		arg->type = PRINT_TYPE;
 		arg->typecast.type = arg->atom.atom;
@@ -2571,6 +2642,11 @@ process_func_handler(struct event_format *event, struct pevent_function_handler
 	next_arg = &(arg->func.args);
 	for (i = 0; i < func->nr_args; i++) {
 		farg = alloc_arg();
+		if (!farg) {
+			do_warning("%s: not enough memory!", __func__);
+			return EVENT_ERROR;
+		}
+
 		type = process_arg(event, farg, &token);
 		if (i < (func->nr_args - 1))
 			test = ",";
@@ -2737,6 +2813,10 @@ static int event_read_print_args(struct event_format *event, struct print_arg **
 		}
 
 		arg = alloc_arg();
+		if (!arg) {
+			do_warning("%s: not enough memory!", __func__);
+			return -1;
+		}
 
 		type = process_arg(event, arg, &token);
 
@@ -3635,6 +3715,10 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 	 * The first arg is the IP pointer.
 	 */
 	args = alloc_arg();
+	if (!args) {
+		do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+		return NULL;
+	}
 	arg = args;
 	arg->next = NULL;
 	next = &arg->next;
@@ -3697,6 +3781,11 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 				val = pevent_read_number(pevent, bptr, vsize);
 				bptr += vsize;
 				arg = alloc_arg();
+				if (!arg) {
+					do_warning("%s(%d): not enough memory!",
+						   __func__, __LINE__);
+					goto out_free;
+				}
 				arg->next = NULL;
 				arg->type = PRINT_ATOM;
 				if (asprintf(&arg->atom.atom, "%lld", val) < 0) {
@@ -3715,6 +3804,11 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 				break;
 			case 's':
 				arg = alloc_arg();
+				if (!arg) {
+					do_warning("%s(%d): not enough memory!",
+						   __func__, __LINE__);
+					goto out_free;
+				}
 				arg->next = NULL;
 				arg->type = PRINT_BSTRING;
 				arg->string.string = strdup(bptr);
@@ -4876,6 +4970,10 @@ enum pevent_errno pevent_parse_event(struct pevent *pevent, const char *buf,
 		list = &event->print_fmt.args;
 		for (field = event->format.fields; field; field = field->next) {
 			arg = alloc_arg();
+			if (!arg) {
+				event->flags |= EVENT_FL_FAILED;
+				return PEVENT_ERRNO__OLD_FTRACE_ARG_FAILED;
+			}
 			arg->type = PRINT_FIELD;
 			arg->field.name = strdup(field->name);
 			if (!arg->field.name) {
-- 
1.7.11.4

Re: [RFC 0/4] Some libtraceevent cleanups/simplifications

[Namhyung Kim]

On Mon, 17 Sep 2012 17:50:45 -0300, Arnaldo Carvalho de Melo wrote:
> Hi Steven,
>
> 	Please take a look, while looking at how to do some stuff in 'perf
> test' just for parsing the /format file I ended up with this series, lemme know
> if I can add your Acked-by and push via my perf/core branch.

With my add-on patch, the series looks good to me.  You can add my

  Reviewed-by: Namhyung Kim <namhyung@kernel.org>

if you want. :)

Thanks,
Namhyung

Re: [PATCH] tools lib traceevent: Handle alloc_arg failure

[Ingo Molnar]

* Namhyung Kim <namhyung@kernel.org> wrote:

> +		if (!left) {
> +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> +			goto out_free;

> +		if (!right) {
> +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> +			goto out_free;
> +		}

> +		if (!left) {
> +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> +			goto out_free;
> +		}

> +		if (!left) {
> +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> +			goto out_free;
> +		}

> +		if (!right) {
> +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> +			goto out_free;
> +		}

> +		if (!left) {
> +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> +			goto out_free;
> +		}

These repetitive patterns are seriously uglifying the code and 
are crying out loud for a out_war_free label:

		if (!left)
			goto out_warn_free;

(The function here seems to be rather large as well, making it a 
possible candidate for shrinkage/splitup.)

Thanks,

	Ingo

Re: [PATCH] tools lib traceevent: Handle alloc_arg failure

[Namhyung Kim]

Hi Ingo,

2012-09-19 (수), 13:42 +0200, Ingo Molnar:
> * Namhyung Kim <namhyung@kernel.org> wrote:
> 
> > +		if (!left) {
> > +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> > +			goto out_free;
> 
> > +		if (!right) {
> > +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> > +			goto out_free;
> > +		}
> 
> > +		if (!left) {
> > +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> > +			goto out_free;
> > +		}
> 
> > +		if (!left) {
> > +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> > +			goto out_free;
> > +		}
> 
> > +		if (!right) {
> > +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> > +			goto out_free;
> > +		}
> 
> > +		if (!left) {
> > +			do_warning("%s(%d): not enough memory!", __func__, __LINE__);
> > +			goto out_free;
> > +		}
> 
> These repetitive patterns are seriously uglifying the code and 
> are crying out loud for a out_war_free label:
> 
> 		if (!left)
> 			goto out_warn_free;

Yeah, I agree.  But I wanted to add a bit more helpful (to developers)
info - function name and line number - rather than just "not enough
memory" message.  Maybe we could change do_warning to emit such info
automatically.

Thanks,
Namhyung

Re: [PATCH] tools lib traceevent: Handle alloc_arg failure

[Steven Rostedt]

On Wed, 2012-09-19 at 21:26 +0900, Namhyung Kim wrote:
> Hi Ingo,
> 

> Yeah, I agree.  But I wanted to add a bit more helpful (to developers)
> info - function name and line number - rather than just "not enough
> memory" message.  Maybe we could change do_warning to emit such info
> automatically.

But these only fail if you run out of memory for the tool. In that case,
I don't think it's that important which allocation failed.

-- Steve

Re: [PATCH] tools lib traceevent: Handle alloc_arg failure

[Namhyung Kim]

Hi Steve,

2012-09-19 (수), 08:41 -0400, Steven Rostedt:
> On Wed, 2012-09-19 at 21:26 +0900, Namhyung Kim wrote:
> > Yeah, I agree.  But I wanted to add a bit more helpful (to developers)
> > info - function name and line number - rather than just "not enough
> > memory" message.  Maybe we could change do_warning to emit such info
> > automatically.
> 
> But these only fail if you run out of memory for the tool. In that case,
> I don't think it's that important which allocation failed.

Okay, I'll send v2 tomorrow according to Ingo's suggestion.

Thanks,
Namhyung

[PATCH v2] tools lib traceevent: Handle alloc_arg failure

[Namhyung Kim]

Now alloc_arg returns NULL if memory allocation failed, it should be
handled on callsites properly.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
Hmm.. how about this?  Do you want that the __func__ part also gets removed?

 tools/lib/traceevent/event-parse.c | 97 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 95 insertions(+), 2 deletions(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index e8e0fe0443a4..2e3fc5ec9cc6 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -1565,6 +1565,14 @@ process_cond(struct event_format *event, struct print_arg *top, char **tok)
 	left = alloc_arg();
 	right = alloc_arg();
 
+	if (!arg || !left || !right) {
+		do_warning("%s: not enough memory!", __func__);
+		/* arg will be freed at out_free */
+		free_arg(left);
+		free_arg(right);
+		goto out_free;
+	}
+
 	arg->type = PRINT_OP;
 	arg->op.left = left;
 	arg->op.right = right;
@@ -1607,6 +1615,12 @@ process_array(struct event_format *event, struct print_arg *top, char **tok)
 	char *token = NULL;
 
 	arg = alloc_arg();
+	if (!arg) {
+		do_warning("%s: not enough memory!", __func__);
+		/* '*tok' is set to top->op.op.  No need to free. */
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
 
 	*tok = NULL;
 	type = process_arg(event, arg, &token);
@@ -1726,10 +1740,16 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 
 		/* make an empty left */
 		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
 		left->type = PRINT_NULL;
 		arg->op.left = left;
 
 		right = alloc_arg();
+		if (!right)
+			goto out_warn_free;
+
 		arg->op.right = right;
 
 		/* do not free the token, it belongs to an op */
@@ -1739,6 +1759,9 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 	} else if (strcmp(token, "?") == 0) {
 
 		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
 		/* copy the top arg to the left */
 		*left = *arg;
 
@@ -1766,6 +1789,8 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		   strcmp(token, "!=") == 0) {
 
 		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
 
 		/* copy the top arg to the left */
 		*left = *arg;
@@ -1796,7 +1821,7 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 			new_atom = realloc(left->atom.atom,
 					    strlen(left->atom.atom) + 3);
 			if (!new_atom)
-				goto out_free;
+				goto out_warn_free;
 
 			left->atom.atom = new_atom;
 			strcat(left->atom.atom, " *");
@@ -1808,12 +1833,18 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		}
 
 		right = alloc_arg();
+		if (!right)
+			goto out_warn_free;
+
 		type = process_arg_token(event, right, tok, type);
 		arg->op.right = right;
 
 	} else if (strcmp(token, "[") == 0) {
 
 		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
 		*left = *arg;
 
 		arg->type = PRINT_OP;
@@ -1845,7 +1876,9 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 
 	return type;
 
- out_free:
+out_warn_free:
+	do_warning("%s: not enough memory!", __func__);
+out_free:
 	free_token(token);
 	*tok = NULL;
 	return EVENT_ERROR;
@@ -2201,6 +2234,8 @@ process_fields(struct event_format *event, struct print_flag_sym **list, char **
 			break;
 
 		arg = alloc_arg();
+		if (!arg)
+			goto out_free;
 
 		free_token(token);
 		type = process_arg(event, arg, &token);
@@ -2227,6 +2262,8 @@ process_fields(struct event_format *event, struct print_flag_sym **list, char **
 
 		free_arg(arg);
 		arg = alloc_arg();
+		if (!arg)
+			goto out_free;
 
 		free_token(token);
 		type = process_arg(event, arg, &token);
@@ -2271,6 +2308,10 @@ process_flags(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_FLAGS;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
 
 	type = process_arg(event, field, &token);
 
@@ -2318,6 +2359,10 @@ process_symbols(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_SYMBOL;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
 
 	type = process_arg(event, field, &token);
 	if (test_type_token(type, token, EVENT_DELIM, ","))
@@ -2350,6 +2395,11 @@ process_hex(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_HEX;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
+
 	type = process_arg(event, field, &token);
 
 	if (test_type_token(type, token, EVENT_DELIM, ","))
@@ -2360,6 +2410,12 @@ process_hex(struct event_format *event, struct print_arg *arg, char **tok)
 	free_token(token);
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
+
 	type = process_arg(event, field, &token);
 
 	if (test_type_token(type, token, EVENT_DELIM, ")"))
@@ -2417,6 +2473,12 @@ process_dynamic_array(struct event_format *event, struct print_arg *arg, char **
 
 	free_token(token);
 	arg = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
+
 	type = process_arg(event, arg, &token);
 	if (type == EVENT_ERROR)
 		goto out_free_arg;
@@ -2476,6 +2538,10 @@ process_paren(struct event_format *event, struct print_arg *arg, char **tok)
 		}
 
 		item_arg = alloc_arg();
+		if (!item_arg) {
+			do_warning("%s: not enough memory!", __func__);
+			goto out_free;
+		}
 
 		arg->type = PRINT_TYPE;
 		arg->typecast.type = arg->atom.atom;
@@ -2571,6 +2637,11 @@ process_func_handler(struct event_format *event, struct pevent_function_handler
 	next_arg = &(arg->func.args);
 	for (i = 0; i < func->nr_args; i++) {
 		farg = alloc_arg();
+		if (!farg) {
+			do_warning("%s: not enough memory!", __func__);
+			return EVENT_ERROR;
+		}
+
 		type = process_arg(event, farg, &token);
 		if (i < (func->nr_args - 1))
 			test = ",";
@@ -2737,6 +2808,10 @@ static int event_read_print_args(struct event_format *event, struct print_arg **
 		}
 
 		arg = alloc_arg();
+		if (!arg) {
+			do_warning("%s: not enough memory!", __func__);
+			return -1;
+		}
 
 		type = process_arg(event, arg, &token);
 
@@ -3635,6 +3710,10 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 	 * The first arg is the IP pointer.
 	 */
 	args = alloc_arg();
+	if (!args) {
+		do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+		return NULL;
+	}
 	arg = args;
 	arg->next = NULL;
 	next = &arg->next;
@@ -3697,6 +3776,11 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 				val = pevent_read_number(pevent, bptr, vsize);
 				bptr += vsize;
 				arg = alloc_arg();
+				if (!arg) {
+					do_warning("%s(%d): not enough memory!",
+						   __func__, __LINE__);
+					goto out_free;
+				}
 				arg->next = NULL;
 				arg->type = PRINT_ATOM;
 				if (asprintf(&arg->atom.atom, "%lld", val) < 0) {
@@ -3715,6 +3799,11 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 				break;
 			case 's':
 				arg = alloc_arg();
+				if (!arg) {
+					do_warning("%s(%d): not enough memory!",
+						   __func__, __LINE__);
+					goto out_free;
+				}
 				arg->next = NULL;
 				arg->type = PRINT_BSTRING;
 				arg->string.string = strdup(bptr);
@@ -4876,6 +4965,10 @@ enum pevent_errno pevent_parse_event(struct pevent *pevent, const char *buf,
 		list = &event->print_fmt.args;
 		for (field = event->format.fields; field; field = field->next) {
 			arg = alloc_arg();
+			if (!arg) {
+				event->flags |= EVENT_FL_FAILED;
+				return PEVENT_ERRNO__OLD_FTRACE_ARG_FAILED;
+			}
 			arg->type = PRINT_FIELD;
 			arg->field.name = strdup(field->name);
 			if (!arg->field.name) {
-- 
1.7.11.4

[tip:perf/core] tools lib traceevent: Handle alloc_arg failure

[tip-bot for Namhyung Kim]

Commit-ID:  b1ac754b67b5a875d63bee880f60ccb0c6bd8899
Gitweb:     http://git.kernel.org/tip/b1ac754b67b5a875d63bee880f60ccb0c6bd8899
Author:     Namhyung Kim <namhyung@kernel.org>
AuthorDate: Thu, 20 Sep 2012 11:09:19 +0900
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Mon, 24 Sep 2012 12:31:52 -0300

tools lib traceevent: Handle alloc_arg failure

Now alloc_arg returns NULL if memory allocation failed, it should be
handled on callsites properly.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/87k3vpzbqo.fsf_-_@sejong.aot.lge.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/traceevent/event-parse.c |   97 +++++++++++++++++++++++++++++++++++-
 1 files changed, 95 insertions(+), 2 deletions(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index 1fa71ca..17c9221 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -1565,6 +1565,14 @@ process_cond(struct event_format *event, struct print_arg *top, char **tok)
 	left = alloc_arg();
 	right = alloc_arg();
 
+	if (!arg || !left || !right) {
+		do_warning("%s: not enough memory!", __func__);
+		/* arg will be freed at out_free */
+		free_arg(left);
+		free_arg(right);
+		goto out_free;
+	}
+
 	arg->type = PRINT_OP;
 	arg->op.left = left;
 	arg->op.right = right;
@@ -1607,6 +1615,12 @@ process_array(struct event_format *event, struct print_arg *top, char **tok)
 	char *token = NULL;
 
 	arg = alloc_arg();
+	if (!arg) {
+		do_warning("%s: not enough memory!", __func__);
+		/* '*tok' is set to top->op.op.  No need to free. */
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
 
 	*tok = NULL;
 	type = process_arg(event, arg, &token);
@@ -1725,10 +1739,16 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 
 		/* make an empty left */
 		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
 		left->type = PRINT_NULL;
 		arg->op.left = left;
 
 		right = alloc_arg();
+		if (!right)
+			goto out_warn_free;
+
 		arg->op.right = right;
 
 		/* do not free the token, it belongs to an op */
@@ -1738,6 +1758,9 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 	} else if (strcmp(token, "?") == 0) {
 
 		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
 		/* copy the top arg to the left */
 		*left = *arg;
 
@@ -1766,6 +1789,8 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		   strcmp(token, "!=") == 0) {
 
 		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
 
 		/* copy the top arg to the left */
 		*left = *arg;
@@ -1797,7 +1822,7 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 			new_atom = realloc(left->atom.atom,
 					    strlen(left->atom.atom) + 3);
 			if (!new_atom)
-				goto out_free;
+				goto out_warn_free;
 
 			left->atom.atom = new_atom;
 			strcat(left->atom.atom, " *");
@@ -1809,12 +1834,18 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		}
 
 		right = alloc_arg();
+		if (!right)
+			goto out_warn_free;
+
 		type = process_arg_token(event, right, tok, type);
 		arg->op.right = right;
 
 	} else if (strcmp(token, "[") == 0) {
 
 		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
 		*left = *arg;
 
 		arg->type = PRINT_OP;
@@ -1847,7 +1878,9 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 
 	return type;
 
- out_free:
+out_warn_free:
+	do_warning("%s: not enough memory!", __func__);
+out_free:
 	free_token(token);
 	*tok = NULL;
 	return EVENT_ERROR;
@@ -2203,6 +2236,8 @@ process_fields(struct event_format *event, struct print_flag_sym **list, char **
 			break;
 
 		arg = alloc_arg();
+		if (!arg)
+			goto out_free;
 
 		free_token(token);
 		type = process_arg(event, arg, &token);
@@ -2229,6 +2264,8 @@ process_fields(struct event_format *event, struct print_flag_sym **list, char **
 
 		free_arg(arg);
 		arg = alloc_arg();
+		if (!arg)
+			goto out_free;
 
 		free_token(token);
 		type = process_arg(event, arg, &token);
@@ -2275,6 +2312,10 @@ process_flags(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_FLAGS;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
 
 	type = process_arg(event, field, &token);
 
@@ -2324,6 +2365,10 @@ process_symbols(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_SYMBOL;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
 
 	type = process_arg(event, field, &token);
 	if (test_type_token(type, token, EVENT_DELIM, ","))
@@ -2358,6 +2403,11 @@ process_hex(struct event_format *event, struct print_arg *arg, char **tok)
 	arg->type = PRINT_HEX;
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		goto out_free;
+	}
+
 	type = process_arg(event, field, &token);
 
 	if (test_type_token(type, token, EVENT_DELIM, ","))
@@ -2368,6 +2418,12 @@ process_hex(struct event_format *event, struct print_arg *arg, char **tok)
 	free_token(token);
 
 	field = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
+
 	type = process_arg(event, field, &token);
 
 	if (test_type_token(type, token, EVENT_DELIM, ")"))
@@ -2425,6 +2481,12 @@ process_dynamic_array(struct event_format *event, struct print_arg *arg, char **
 
 	free_token(token);
 	arg = alloc_arg();
+	if (!field) {
+		do_warning("%s: not enough memory!", __func__);
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
+
 	type = process_arg(event, arg, &token);
 	if (type == EVENT_ERROR)
 		goto out_free_arg;
@@ -2484,6 +2546,10 @@ process_paren(struct event_format *event, struct print_arg *arg, char **tok)
 		}
 
 		item_arg = alloc_arg();
+		if (!item_arg) {
+			do_warning("%s: not enough memory!", __func__);
+			goto out_free;
+		}
 
 		arg->type = PRINT_TYPE;
 		arg->typecast.type = arg->atom.atom;
@@ -2579,6 +2645,11 @@ process_func_handler(struct event_format *event, struct pevent_function_handler
 	next_arg = &(arg->func.args);
 	for (i = 0; i < func->nr_args; i++) {
 		farg = alloc_arg();
+		if (!farg) {
+			do_warning("%s: not enough memory!", __func__);
+			return EVENT_ERROR;
+		}
+
 		type = process_arg(event, farg, &token);
 		if (i < (func->nr_args - 1))
 			test = ",";
@@ -2745,6 +2816,10 @@ static int event_read_print_args(struct event_format *event, struct print_arg **
 		}
 
 		arg = alloc_arg();
+		if (!arg) {
+			do_warning("%s: not enough memory!", __func__);
+			return -1;
+		}
 
 		type = process_arg(event, arg, &token);
 
@@ -3643,6 +3718,10 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 	 * The first arg is the IP pointer.
 	 */
 	args = alloc_arg();
+	if (!args) {
+		do_warning("%s(%d): not enough memory!", __func__, __LINE__);
+		return NULL;
+	}
 	arg = args;
 	arg->next = NULL;
 	next = &arg->next;
@@ -3705,6 +3784,11 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 				val = pevent_read_number(pevent, bptr, vsize);
 				bptr += vsize;
 				arg = alloc_arg();
+				if (!arg) {
+					do_warning("%s(%d): not enough memory!",
+						   __func__, __LINE__);
+					goto out_free;
+				}
 				arg->next = NULL;
 				arg->type = PRINT_ATOM;
 				if (asprintf(&arg->atom.atom, "%lld", val) < 0) {
@@ -3723,6 +3807,11 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
 				break;
 			case 's':
 				arg = alloc_arg();
+				if (!arg) {
+					do_warning("%s(%d): not enough memory!",
+						   __func__, __LINE__);
+					goto out_free;
+				}
 				arg->next = NULL;
 				arg->type = PRINT_BSTRING;
 				arg->string.string = strdup(bptr);
@@ -4878,6 +4967,10 @@ enum pevent_errno __pevent_parse_format(struct event_format **eventp,
 		list = &event->print_fmt.args;
 		for (field = event->format.fields; field; field = field->next) {
 			arg = alloc_arg();
+			if (!arg) {
+				event->flags |= EVENT_FL_FAILED;
+				return PEVENT_ERRNO__OLD_FTRACE_ARG_FAILED;
+			}
 			arg->type = PRINT_FIELD;
 			arg->field.name = strdup(field->name);
 			if (!arg->field.name) {