* [PATCH 1/3] trace-cmd traceevent: Add append() function helper for appending strings
2020-06-25 10:04 [PATCH 0/3] Synchronize libtraceevent with kernel tree Tzvetomir Stoyanov (VMware)
@ 2020-06-25 10:04 ` Tzvetomir Stoyanov (VMware)
2020-06-25 10:04 ` [PATCH 2/3] trace-cmd traceevent: Handle __attribute__((user)) in field names Tzvetomir Stoyanov (VMware)
2020-06-25 10:04 ` [PATCH 3/3] trace-cmd traceevent: Add handler for __builtin_expect() Tzvetomir Stoyanov (VMware)
2 siblings, 0 replies; 4+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2020-06-25 10:04 UTC (permalink / raw)
To: rostedt; +Cc: linux-trace-devel
From: Steven Rostedt (VMware) <rostedt@goodmis.org>
There's several locations that open code realloc and strcat() to append
text to strings. Add an append() function that takes a delimiter and a
string to append to another string.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jaewon Lim <jaewon31.kim@samsung.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Kook <keescook@chromium.org>
Cc: linux-mm@kvack.org
Cc: linux-trace-devel@vger.kernel.org
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: http://lore.kernel.org/lkml/20200324200956.515118403@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
lib/traceevent/event-parse.c | 98 +++++++++++++++---------------------
1 file changed, 40 insertions(+), 58 deletions(-)
diff --git a/lib/traceevent/event-parse.c b/lib/traceevent/event-parse.c
index d8115d7a..6249dacd 100644
--- a/lib/traceevent/event-parse.c
+++ b/lib/traceevent/event-parse.c
@@ -1425,6 +1425,19 @@ static unsigned int type_size(const char *name)
return 0;
}
+static int append(char **buf, const char *delim, const char *str)
+{
+ char *new_buf;
+
+ new_buf = realloc(*buf, strlen(*buf) + strlen(delim) + strlen(str) + 1);
+ if (!new_buf)
+ return -1;
+ strcat(new_buf, delim);
+ strcat(new_buf, str);
+ *buf = new_buf;
+ return 0;
+}
+
static int event_read_fields(struct tep_event *event, struct tep_format_field **fields)
{
struct tep_format_field *field = NULL;
@@ -1432,6 +1445,7 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
char *token;
char *last_token;
int count = 0;
+ int ret;
do {
unsigned int size_dynamic = 0;
@@ -1490,24 +1504,15 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
field->flags |= TEP_FIELD_IS_POINTER;
if (field->type) {
- char *new_type;
- new_type = realloc(field->type,
- strlen(field->type) +
- strlen(last_token) + 2);
- if (!new_type) {
- free(last_token);
- goto fail;
- }
- field->type = new_type;
- strcat(field->type, " ");
- strcat(field->type, last_token);
+ ret = append(&field->type, " ", last_token);
free(last_token);
+ if (ret < 0)
+ goto fail;
} else
field->type = last_token;
last_token = token;
continue;
}
-
break;
}
@@ -1523,8 +1528,6 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
if (strcmp(token, "[") == 0) {
enum tep_event_type last_type = type;
char *brackets = token;
- char *new_brackets;
- int len;
field->flags |= TEP_FIELD_IS_ARRAY;
@@ -1536,29 +1539,27 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
field->arraylen = 0;
while (strcmp(token, "]") != 0) {
+ const char *delim;
+
if (last_type == TEP_EVENT_ITEM &&
type == TEP_EVENT_ITEM)
- len = 2;
+ delim = " ";
else
- len = 1;
+ delim = "";
+
last_type = type;
- new_brackets = realloc(brackets,
- strlen(brackets) +
- strlen(token) + len);
- if (!new_brackets) {
+ ret = append(&brackets, delim, token);
+ if (ret < 0) {
free(brackets);
goto fail;
}
- brackets = new_brackets;
- if (len == 2)
- strcat(brackets, " ");
- strcat(brackets, token);
/* We only care about the last token */
field->arraylen = strtoul(token, NULL, 0);
free_token(token);
type = read_token(&token);
if (type == TEP_EVENT_NONE) {
+ free(brackets);
do_warning_event(event, "failed to find token");
goto fail;
}
@@ -1566,13 +1567,11 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
free_token(token);
- new_brackets = realloc(brackets, strlen(brackets) + 2);
- if (!new_brackets) {
+ ret = append(&brackets, "", "]");
+ if (ret < 0) {
free(brackets);
goto fail;
}
- brackets = new_brackets;
- strcat(brackets, "]");
/* add brackets to type */
@@ -1582,34 +1581,23 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
* the format: type [] item;
*/
if (type == TEP_EVENT_ITEM) {
- char *new_type;
- new_type = realloc(field->type,
- strlen(field->type) +
- strlen(field->name) +
- strlen(brackets) + 2);
- if (!new_type) {
+ ret = append(&field->type, " ", field->name);
+ if (ret < 0) {
free(brackets);
goto fail;
}
- field->type = new_type;
- strcat(field->type, " ");
- strcat(field->type, field->name);
+ ret = append(&field->type, "", brackets);
+
size_dynamic = type_size(field->name);
free_token(field->name);
- strcat(field->type, brackets);
field->name = field->alias = token;
type = read_token(&token);
} else {
- char *new_type;
- new_type = realloc(field->type,
- strlen(field->type) +
- strlen(brackets) + 1);
- if (!new_type) {
+ ret = append(&field->type, "", brackets);
+ if (ret < 0) {
free(brackets);
goto fail;
}
- field->type = new_type;
- strcat(field->type, brackets);
}
free(brackets);
}
@@ -2046,19 +2034,16 @@ process_op(struct tep_event *event, struct tep_print_arg *arg, char **tok)
/* could just be a type pointer */
if ((strcmp(arg->op.op, "*") == 0) &&
type == TEP_EVENT_DELIM && (strcmp(token, ")") == 0)) {
- char *new_atom;
+ int ret;
if (left->type != TEP_PRINT_ATOM) {
do_warning_event(event, "bad pointer type");
goto out_free;
}
- new_atom = realloc(left->atom.atom,
- strlen(left->atom.atom) + 3);
- if (!new_atom)
+ ret = append(&left->atom.atom, " ", "*");
+ if (ret < 0)
goto out_warn_free;
- left->atom.atom = new_atom;
- strcat(left->atom.atom, " *");
free(arg->op.op);
*arg = *left;
free(left);
@@ -3151,18 +3136,15 @@ process_arg_token(struct tep_event *event, struct tep_print_arg *arg,
}
/* atoms can be more than one token long */
while (type == TEP_EVENT_ITEM) {
- char *new_atom;
- new_atom = realloc(atom,
- strlen(atom) + strlen(token) + 2);
- if (!new_atom) {
+ int ret;
+
+ ret = append(&atom, " ", token);
+ if (ret < 0) {
free(atom);
*tok = NULL;
free_token(token);
return TEP_EVENT_ERROR;
}
- atom = new_atom;
- strcat(atom, " ");
- strcat(atom, token);
free_token(token);
type = read_token_item(&token);
}
--
2.26.2
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 2/3] trace-cmd traceevent: Handle __attribute__((user)) in field names
2020-06-25 10:04 [PATCH 0/3] Synchronize libtraceevent with kernel tree Tzvetomir Stoyanov (VMware)
2020-06-25 10:04 ` [PATCH 1/3] trace-cmd traceevent: Add append() function helper for appending strings Tzvetomir Stoyanov (VMware)
@ 2020-06-25 10:04 ` Tzvetomir Stoyanov (VMware)
2020-06-25 10:04 ` [PATCH 3/3] trace-cmd traceevent: Add handler for __builtin_expect() Tzvetomir Stoyanov (VMware)
2 siblings, 0 replies; 4+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2020-06-25 10:04 UTC (permalink / raw)
To: rostedt; +Cc: linux-trace-devel
From: Steven Rostedt (VMware) <rostedt@goodmis.org>
Commit c61f13eaa1ee1 ("gcc-plugins: Add structleak for more stack
initialization") added "__attribute__((user))" to the user when
stackleak detector is enabled. This now appears in the field format of
system call trace events for system calls that have user buffers. The
"__attribute__((user))" breaks the parsing in libtraceevent. That needs
to be handled.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jaewon Kim <jaewon31.kim@samsung.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Kook <keescook@chromium.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-mm@kvack.org
Cc: linux-trace-devel@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200324200956.663647256@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
lib/traceevent/event-parse.c | 39 +++++++++++++++++++++++++++++++++++-
1 file changed, 38 insertions(+), 1 deletion(-)
diff --git a/lib/traceevent/event-parse.c b/lib/traceevent/event-parse.c
index 6249dacd..7e9cd9bb 100644
--- a/lib/traceevent/event-parse.c
+++ b/lib/traceevent/event-parse.c
@@ -1444,6 +1444,7 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
enum tep_event_type type;
char *token;
char *last_token;
+ char *delim = " ";
int count = 0;
int ret;
@@ -1504,13 +1505,49 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
field->flags |= TEP_FIELD_IS_POINTER;
if (field->type) {
- ret = append(&field->type, " ", last_token);
+ ret = append(&field->type, delim, last_token);
free(last_token);
if (ret < 0)
goto fail;
} else
field->type = last_token;
last_token = token;
+ delim = " ";
+ continue;
+ }
+
+ /* Handle __attribute__((user)) */
+ if ((type == TEP_EVENT_DELIM) &&
+ strcmp("__attribute__", last_token) == 0 &&
+ token[0] == '(') {
+ int depth = 1;
+ int ret;
+
+ ret = append(&field->type, " ", last_token);
+ ret |= append(&field->type, "", "(");
+ if (ret < 0)
+ goto fail;
+
+ delim = " ";
+ while ((type = read_token(&token)) != TEP_EVENT_NONE) {
+ if (type == TEP_EVENT_DELIM) {
+ if (token[0] == '(')
+ depth++;
+ else if (token[0] == ')')
+ depth--;
+ if (!depth)
+ break;
+ ret = append(&field->type, "", token);
+ delim = "";
+ } else {
+ ret = append(&field->type, delim, token);
+ delim = " ";
+ }
+ if (ret < 0)
+ goto fail;
+ free(last_token);
+ last_token = token;
+ }
continue;
}
break;
--
2.26.2
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 3/3] trace-cmd traceevent: Add handler for __builtin_expect()
2020-06-25 10:04 [PATCH 0/3] Synchronize libtraceevent with kernel tree Tzvetomir Stoyanov (VMware)
2020-06-25 10:04 ` [PATCH 1/3] trace-cmd traceevent: Add append() function helper for appending strings Tzvetomir Stoyanov (VMware)
2020-06-25 10:04 ` [PATCH 2/3] trace-cmd traceevent: Handle __attribute__((user)) in field names Tzvetomir Stoyanov (VMware)
@ 2020-06-25 10:04 ` Tzvetomir Stoyanov (VMware)
2 siblings, 0 replies; 4+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2020-06-25 10:04 UTC (permalink / raw)
To: rostedt; +Cc: linux-trace-devel
From: Steven Rostedt (VMware) <rostedt@goodmis.org>
In order to move pointer checks like IS_ERR_VALUE() out of the hotpath
and into the reader path of a trace event, user space tools need to be
able to parse that. IS_ERR_VALUE() is defined as:
#define IS_ERR_VALUE() unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
Which eventually turns into:
__builtin_expect(!!((unsigned long)(void *)(x) >= (unsigned long)-4095), 0)
Now the traceevent parser can handle most of that except for the
__builtin_expect(), which needs to be added.
Link: https://lore.kernel.org/linux-mm/20200320055823.27089-3-jaewon31.kim@samsung.com/
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jaewon Kim <jaewon31.kim@samsung.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Kook <keescook@chromium.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-mm@kvack.org
Cc: linux-trace-devel@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200324200956.821799393@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
lib/traceevent/event-parse.c | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)
diff --git a/lib/traceevent/event-parse.c b/lib/traceevent/event-parse.c
index 7e9cd9bb..ee16be96 100644
--- a/lib/traceevent/event-parse.c
+++ b/lib/traceevent/event-parse.c
@@ -3084,6 +3084,37 @@ err:
return TEP_EVENT_ERROR;
}
+static enum tep_event_type
+process_builtin_expect(struct tep_event *event, struct tep_print_arg *arg, char **tok)
+{
+ enum tep_event_type type;
+ char *token = NULL;
+
+ /* Handle __builtin_expect( cond, #) */
+ type = process_arg(event, arg, &token);
+
+ if (type != TEP_EVENT_DELIM || token[0] != ',')
+ goto out_free;
+
+ free_token(token);
+
+ /* We don't care what the second parameter is of the __builtin_expect() */
+ if (read_expect_type(TEP_EVENT_ITEM, &token) < 0)
+ goto out_free;
+
+ if (read_expected(TEP_EVENT_DELIM, ")") < 0)
+ goto out_free;
+
+ free_token(token);
+ type = read_token_item(tok);
+ return type;
+
+out_free:
+ free_token(token);
+ *tok = NULL;
+ return TEP_EVENT_ERROR;
+}
+
static enum tep_event_type
process_function(struct tep_event *event, struct tep_print_arg *arg,
char *token, char **tok)
@@ -3128,6 +3159,10 @@ process_function(struct tep_event *event, struct tep_print_arg *arg,
free_token(token);
return process_dynamic_array_len(event, arg, tok);
}
+ if (strcmp(token, "__builtin_expect") == 0) {
+ free_token(token);
+ return process_builtin_expect(event, arg, tok);
+ }
func = find_func_handler(event->tep, token);
if (func) {
--
2.26.2
^ permalink raw reply related [flat|nested] 4+ messages in thread