* [PATCH v6 01/12] libtracefs: New APIs for dynamic events
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:03 ` Tzvetomir Stoyanov (VMware)
2021-11-11 22:33 ` Steven Rostedt
2021-11-08 8:03 ` [PATCH v6 02/12] libtracefs: New APIs for kprobe allocation Tzvetomir Stoyanov (VMware)
` (10 subsequent siblings)
11 siblings, 1 reply; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:03 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
Ftrace supports dynamic events, created by the user - kprobes, uprobes,
eprobes and synthetic events. There are two interfaces for managing
these events - new common "dynamic_events" file and event specific
"kprobe_events", "uprobe_events", "synthetic_events" files. The
configuration syntax for all dynamic events is almost the same.
To simplify support of dynamic events in the tracefs library, new
APIs are introduced. They handle both configuration interfaces -
the common "dynamic_events" file is preferred, if available.
On the old kernels, where this file is missing, the event
specific files are used. The new APIs can be used to create,
delete and get ftrace dynamic events from any type:
enum tracefs_dynevent_type;
tracefs_dynevent_create();
tracefs_dynevent_destroy();
tracefs_dynevent_destroy_all();
tracefs_dynevent_free();
tracefs_dynevent_list_free();
tracefs_dynevent_get_all();
There is no public API for allocation of a new dynamic event, as that
logic is specific for each dynamic event type.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
include/tracefs-local.h | 18 +
include/tracefs.h | 23 ++
src/Makefile | 1 +
src/tracefs-dynevents.c | 720 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 762 insertions(+)
create mode 100644 src/tracefs-dynevents.c
diff --git a/include/tracefs-local.h b/include/tracefs-local.h
index 684eccf..a59e806 100644
--- a/include/tracefs-local.h
+++ b/include/tracefs-local.h
@@ -94,4 +94,22 @@ int synth_add_start_field(struct tracefs_synth *synth,
const char *start_field,
const char *name,
enum tracefs_hist_key_type type);
+
+/* Internal interface for ftrace dynamic events */
+
+struct tracefs_dynevent {
+ char *trace_file;
+ char *prefix;
+ char *system;
+ char *event;
+ char *address;
+ char *format;
+ enum tracefs_dynevent_type type;
+};
+
+struct tracefs_dynevent *
+dynevent_alloc(enum tracefs_dynevent_type type, const char *system,
+ const char *event, const char *address, const char *format);
+int dynevent_get_count(unsigned int types, const char *system);
+
#endif /* _TRACE_FS_LOCAL_H */
diff --git a/include/tracefs.h b/include/tracefs.h
index a2cda30..eceb1f5 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -238,6 +238,29 @@ ssize_t tracefs_trace_pipe_stream(int fd, struct tracefs_instance *instance, int
ssize_t tracefs_trace_pipe_print(struct tracefs_instance *instance, int flags);
void tracefs_trace_pipe_stop(struct tracefs_instance *instance);
+/* Dynamic events */
+struct tracefs_dynevent;
+enum tracefs_dynevent_type {
+ TRACEFS_DYNEVENT_UNKNOWN = 0,
+ TRACEFS_DYNEVENT_KPROBE = 1 << 0,
+ TRACEFS_DYNEVENT_KRETPROBE = 1 << 1,
+ TRACEFS_DYNEVENT_UPROBE = 1 << 2,
+ TRACEFS_DYNEVENT_URETPROBE = 1 << 3,
+ TRACEFS_DYNEVENT_EPROBE = 1 << 4,
+ TRACEFS_DYNEVENT_SYNTH = 1 << 5,
+ TRACEFS_DYNEVENT_MAX = 1 << 6,
+};
+int tracefs_dynevent_create(struct tracefs_dynevent *devent);
+int tracefs_dynevent_destroy(struct tracefs_dynevent *devent, bool force);
+int tracefs_dynevent_destroy_all(unsigned int types, bool force);
+void tracefs_dynevent_free(struct tracefs_dynevent *devent);
+void tracefs_dynevent_list_free(struct tracefs_dynevent **events);
+struct tracefs_dynevent **
+tracefs_dynevent_get_all(unsigned int types, const char *system);
+enum tracefs_dynevent_type
+tracefs_dynevent_info(struct tracefs_dynevent *dynevent, char **system,
+ char **event, char **prefix, char **addr, char **format);
+
enum tracefs_kprobe_type {
TRACEFS_ALL_KPROBES,
TRACEFS_KPROBE,
diff --git a/src/Makefile b/src/Makefile
index 4e38d98..99cd7da 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -11,6 +11,7 @@ OBJS += tracefs-marker.o
OBJS += tracefs-kprobes.o
OBJS += tracefs-hist.o
OBJS += tracefs-filter.o
+OBJS += tracefs-dynevents.o
# Order matters for the the three below
OBJS += sqlhist-lex.o
diff --git a/src/tracefs-dynevents.c b/src/tracefs-dynevents.c
new file mode 100644
index 0000000..f525e8d
--- /dev/null
+++ b/src/tracefs-dynevents.c
@@ -0,0 +1,720 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * Copyright (C) 2021 VMware Inc, Steven Rostedt <rostedt@goodmis.org>
+ *
+ * Updates:
+ * Copyright (C) 2021, VMware, Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
+ *
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+
+#include "tracefs.h"
+#include "tracefs-local.h"
+
+#define DYNEVENTS_EVENTS "dynamic_events"
+#define KPROBE_EVENTS "kprobe_events"
+#define UPROBE_EVENTS "uprobe_events"
+#define SYNTH_EVENTS "synthetic_events"
+#define DYNEVENTS_DEFAULT_GROUP "dynamic"
+
+#define EVENT_INDEX(B) (ffs(B) - 1)
+
+struct dyn_events_desc;
+static int dyn_generic_parse(struct dyn_events_desc *,
+ const char *, char *, struct tracefs_dynevent **);
+static int dyn_synth_parse(struct dyn_events_desc *,
+ const char *, char *, struct tracefs_dynevent **);
+static int dyn_generic_del(struct dyn_events_desc *, struct tracefs_dynevent *);
+static int dyn_synth_del(struct dyn_events_desc *, struct tracefs_dynevent *);
+
+struct dyn_events_desc {
+ enum tracefs_dynevent_type type;
+ const char *file;
+ const char *prefix;
+ int (*del)(struct dyn_events_desc *desc, struct tracefs_dynevent *dyn);
+ int (*parse)(struct dyn_events_desc *desc, const char *group,
+ char *line, struct tracefs_dynevent **ret_dyn);
+} dynevents[] = {
+ {TRACEFS_DYNEVENT_KPROBE, NULL, "p", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_KRETPROBE, NULL, "r", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_UPROBE, NULL, "p", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_URETPROBE, NULL, "r", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_EPROBE, NULL, "e", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_SYNTH, NULL, "s", dyn_synth_del, dyn_synth_parse},
+};
+
+
+
+static int dyn_generic_del(struct dyn_events_desc *desc, struct tracefs_dynevent *dyn)
+{
+ char *str;
+ int ret;
+
+ if (dyn->system)
+ ret = asprintf(&str, "-:%s/%s", dyn->system, dyn->event);
+ else
+ ret = asprintf(&str, "-:%s", dyn->event);
+
+ if (ret < 0)
+ return -1;
+
+ ret = tracefs_instance_file_append(NULL, desc->file, str);
+ free(str);
+
+ return ret < 0 ? ret : 0;
+}
+
+/**
+ * tracefs_dynevent_free - Free a dynamic event context
+ * @devent: Pointer to a dynamic event context
+ *
+ * The dynamic event, described by this context, is not
+ * removed from the system by this API. It only frees the memory.
+ */
+void tracefs_dynevent_free(struct tracefs_dynevent *devent)
+{
+ if (!devent)
+ return;
+ free(devent->system);
+ free(devent->event);
+ free(devent->address);
+ free(devent->format);
+ free(devent->prefix);
+ free(devent->trace_file);
+ free(devent);
+}
+
+static void parse_prefix(char *word, char **prefix, char **system, char **name)
+{
+ char *sav;
+
+ *prefix = NULL;
+ *system = NULL;
+ *name = NULL;
+
+ *prefix = strtok_r(word, ":", &sav);
+ *system = strtok_r(NULL, "/", &sav);
+ if (!(*system))
+ return;
+
+ *name = strtok_r(NULL, " \t", &sav);
+ if (!(*name)) {
+ *name = *system;
+ *system = NULL;
+ }
+}
+
+/*
+ * Parse lines from dynamic_events, kprobe_events and uprobe_events files
+ * PREFIX[:[SYSTEM/]EVENT] [ADDRSS] [FORMAT]
+ */
+static int dyn_generic_parse(struct dyn_events_desc *desc, const char *group,
+ char *line, struct tracefs_dynevent **ret_dyn)
+{
+ struct tracefs_dynevent *dyn;
+ char *word;
+ char *format = NULL;
+ char *address;
+ char *system;
+ char *prefix;
+ char *event;
+ char *sav;
+
+ if (strncmp(line, desc->prefix, strlen(desc->prefix)))
+ return -1;
+
+ word = strtok_r(line, " \t", &sav);
+ if (!word || *word == '\0')
+ return -1;
+
+ parse_prefix(word, &prefix, &system, &event);
+ if (!prefix)
+ return -1;
+
+ if (desc->type != TRACEFS_DYNEVENT_SYNTH) {
+ address = strtok_r(NULL, " \t", &sav);
+ if (!address || *address == '\0')
+ return -1;
+ }
+
+ format = strtok_r(NULL, "", &sav);
+
+ /* KPROBEs and UPROBEs share the same prefix, check the format */
+ if (desc->type & (TRACEFS_DYNEVENT_UPROBE | TRACEFS_DYNEVENT_URETPROBE)) {
+ if (!strchr(address, '/'))
+ return -1;
+ }
+
+ if (group && (!system || strcmp(group, system) != 0))
+ return -1;
+
+ if (!ret_dyn)
+ return 0;
+
+ dyn = calloc(1, sizeof(*dyn));
+ if (!dyn)
+ return -1;
+
+ dyn->type = desc->type;
+ dyn->trace_file = strdup(desc->file);
+ if (!dyn->trace_file)
+ goto error;
+
+ dyn->prefix = strdup(prefix);
+ if (!dyn->prefix)
+ goto error;
+
+ if (system) {
+ dyn->system = strdup(system);
+ if (!dyn->system)
+ goto error;
+ }
+
+ if (event) {
+ dyn->event = strdup(event);
+ if (!dyn->event)
+ goto error;
+ }
+
+ if (address) {
+ dyn->address = strdup(address);
+ if (!dyn->address)
+ goto error;
+ }
+
+ if (format) {
+ dyn->format = strdup(format);
+ if (!dyn->format)
+ goto error;
+ }
+
+ *ret_dyn = dyn;
+ return 0;
+error:
+ tracefs_dynevent_free(dyn);
+ return -1;
+}
+
+static int dyn_synth_del(struct dyn_events_desc *desc, struct tracefs_dynevent *dyn)
+{
+ char *str;
+ int ret;
+
+ if (!strcmp(desc->file, DYNEVENTS_EVENTS))
+ return dyn_generic_del(desc, dyn);
+
+ ret = asprintf(&str, "!%s", dyn->event);
+ if (ret < 0)
+ return -1;
+
+ ret = tracefs_instance_file_append(NULL, desc->file, str);
+ free(str);
+
+ return ret < 0 ? ret : 0;
+}
+
+/*
+ * Parse lines from synthetic_events file
+ * EVENT ARG [ARG]
+ */
+static int dyn_synth_parse(struct dyn_events_desc *desc, const char *group,
+ char *line, struct tracefs_dynevent **ret_dyn)
+{
+ struct tracefs_dynevent *dyn;
+ char *format;
+ char *event;
+ char *sav;
+
+ if (!strcmp(desc->file, DYNEVENTS_EVENTS))
+ return dyn_generic_parse(desc, group, line, ret_dyn);
+
+ /* synthetic_events file has slightly different syntax */
+ event = strtok_r(line, " \t", &sav);
+ if (!event || *event == '\0')
+ return -1;
+
+ format = strtok_r(NULL, "", &sav);
+ if (!format || *format == '\0')
+ return -1;
+
+ if (!ret_dyn)
+ return 0;
+
+ dyn = calloc(1, sizeof(*dyn));
+ if (!dyn)
+ return -1;
+
+ dyn->type = desc->type;
+ dyn->trace_file = strdup(desc->file);
+ if (!dyn->trace_file)
+ goto error;
+
+ dyn->event = strdup(event);
+ if (!dyn->event)
+ goto error;
+
+ dyn->format = strdup(format+1);
+ if (!dyn->format)
+ goto error;
+
+ *ret_dyn = dyn;
+ return 0;
+error:
+ tracefs_dynevent_free(dyn);
+ return -1;
+}
+
+static void init_devent_desc(void)
+{
+ int i;
+
+ BUILD_BUG_ON(ARRAY_SIZE(dynevents) != EVENT_INDEX(TRACEFS_DYNEVENT_MAX));
+
+ /* Use ftrace dynamic_events, if available */
+ if (tracefs_file_exists(NULL, DYNEVENTS_EVENTS)) {
+ for (i = 0; i < EVENT_INDEX(TRACEFS_DYNEVENT_MAX); i++)
+ dynevents[i].file = DYNEVENTS_EVENTS;
+ return;
+ }
+
+ if (tracefs_file_exists(NULL, KPROBE_EVENTS)) {
+ dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_KPROBE)].file = KPROBE_EVENTS;
+ dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_KRETPROBE)].file = KPROBE_EVENTS;
+ }
+ if (tracefs_file_exists(NULL, UPROBE_EVENTS)) {
+ dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_UPROBE)].file = UPROBE_EVENTS;
+ dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_URETPROBE)].file = UPROBE_EVENTS;
+ }
+ if (tracefs_file_exists(NULL, SYNTH_EVENTS)) {
+ dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].file = SYNTH_EVENTS;
+ dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].prefix = "";
+ }
+}
+
+static struct dyn_events_desc *get_devent_desc(enum tracefs_dynevent_type type)
+{
+
+ static bool init;
+
+ if (type >= TRACEFS_DYNEVENT_MAX)
+ return NULL;
+
+ if (!init) {
+ init_devent_desc();
+ init = true;
+ }
+
+ return &dynevents[EVENT_INDEX(type)];
+}
+
+/**
+ * dynevent_alloc - Allocate new dynamic event
+ * @type: Type of the dynamic event
+ * @system: The system name (NULL for the default dynamic)
+ * @event: Name of the event
+ * @addr: The function and offset (or address) to insert the probe
+ * @format: The format string to define the probe.
+ *
+ * Allocate a dynamic event context that will be in the @system group
+ * (or dynamic if @system is NULL). Have the name of @event and
+ * will be associated to @addr, if applicable for that event type
+ * (function name, with or without offset, or a address). And the @format will
+ * define the format of the kprobe.
+ * The dynamic event is not created in the system.
+ *
+ * Return a pointer to a dynamic event context on success, or NULL on error.
+ * The returned pointer must be freed with tracefs_dynevent_free()
+ *
+ * errno will be set to EINVAL if event is NULL.
+ */
+__hidden struct tracefs_dynevent *
+dynevent_alloc(enum tracefs_dynevent_type type, const char *system,
+ const char *event, const char *address, const char *format)
+{
+ struct tracefs_dynevent *devent;
+ struct dyn_events_desc *desc;
+
+ if (!event) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ desc = get_devent_desc(type);
+ if (!desc || !desc->file) {
+ errno = ENOTSUP;
+ return NULL;
+ }
+
+ devent = calloc(1, sizeof(*devent));
+ if (!devent)
+ return NULL;
+
+ devent->type = type;
+ devent->trace_file = strdup(desc->file);
+ if (!devent->trace_file)
+ goto err;
+
+ if (!system)
+ system = DYNEVENTS_DEFAULT_GROUP;
+ devent->system = strdup(system);
+ if (!devent->system)
+ goto err;
+
+ devent->event = strdup(event);
+ if (!devent->event)
+ goto err;
+
+ devent->prefix = strdup(desc->prefix);
+ if (!devent->prefix)
+ goto err;
+
+ if (address) {
+ devent->address = strdup(address);
+ if (!devent->address)
+ goto err;
+ }
+ if (format) {
+ devent->format = strdup(format);
+ if (!devent->format)
+ goto err;
+ }
+
+ return devent;
+err:
+ tracefs_dynevent_free(devent);
+ return NULL;
+}
+
+/**
+ * tracefs_dynevent_create - Create a dynamic event in the system
+ * @devent: Pointer to a dynamic event context, describing the event
+ *
+ * Return 0 on success, or -1 on error.
+ */
+int tracefs_dynevent_create(struct tracefs_dynevent *devent)
+{
+ char *str;
+ int ret;
+
+ if (!devent)
+ return -1;
+
+ if (devent->system && devent->system[0])
+ ret = asprintf(&str, "%s%s%s/%s %s %s\n",
+ devent->prefix, strlen(devent->prefix) ? ":" : "",
+ devent->system, devent->event,
+ devent->address ? devent->address : "",
+ devent->format ? devent->format : "");
+ else
+ ret = asprintf(&str, "%s%s%s %s %s\n",
+ devent->prefix, strlen(devent->prefix) ? ":" : "",
+ devent->event,
+ devent->address ? devent->address : "",
+ devent->format ? devent->format : "");
+ if (ret < 0)
+ return -1;
+
+ ret = tracefs_instance_file_append(NULL, devent->trace_file, str);
+ free(str);
+
+ return ret < 0 ? ret : 0;
+}
+
+static void disable_events(const char *system, const char *event,
+ char **list)
+{
+ struct tracefs_instance *instance;
+ int i;
+
+ /*
+ * Note, this will not fail even on error.
+ * That is because even if something fails, it may still
+ * work enough to clear the kprobes. If that's the case
+ * the clearing after the loop will succeed and the function
+ * is a success, even though other parts had failed. If
+ * one of the kprobe events is enabled in one of the
+ * instances that fail, then the clearing will fail too
+ * and the function will return an error.
+ */
+
+ tracefs_event_disable(NULL, system, event);
+ /* No need to test results */
+
+ if (!list)
+ return;
+
+ for (i = 0; list[i]; i++) {
+ instance = tracefs_instance_alloc(NULL, list[i]);
+ /* If this fails, try the next one */
+ if (!instance)
+ continue;
+ tracefs_event_disable(instance, system, event);
+ tracefs_instance_free(instance);
+ }
+}
+
+/**
+ * tracefs_dynevent_destroy - Remove a dynamic event from the system
+ * @devent: A dynamic event context, describing the dynamic event that will be deleted.
+ * @force: Will attempt to disable all events before removing them.
+ *
+ * The dynamic event context is not freed by this API. It only removes the event from the system.
+ * If there are any enabled events, and @force is not set, then it will error with -1 and errno
+ * to be EBUSY.
+ *
+ * Return 0 on success, or -1 on error.
+ */
+int tracefs_dynevent_destroy(struct tracefs_dynevent *devent, bool force)
+{
+ struct dyn_events_desc *desc;
+ char **instance_list;
+
+ if (!devent)
+ return -1;
+
+ if (force) {
+ instance_list = tracefs_instances(NULL);
+ disable_events(devent->system, devent->event, instance_list);
+ tracefs_list_free(instance_list);
+ }
+
+ desc = get_devent_desc(devent->type);
+ if (!desc)
+ return -1;
+
+ return desc->del(desc, devent);
+}
+
+static int get_all_dynevents(enum tracefs_dynevent_type type, const char *system,
+ struct tracefs_dynevent ***ret_all)
+{
+ struct dyn_events_desc *desc;
+ struct tracefs_dynevent *devent, **tmp, **all = NULL;
+ char *content;
+ int count = 0;
+ char *line;
+ char *next;
+ int ret;
+
+ desc = get_devent_desc(type);
+ if (!desc)
+ return -1;
+
+ content = tracefs_instance_file_read(NULL, desc->file, NULL);
+ if (!content)
+ return -1;
+
+ line = content;
+ do {
+ next = strchr(line, '\n');
+ if (next)
+ *next = '\0';
+ ret = desc->parse(desc, system, line, ret_all ? &devent : NULL);
+ if (!ret) {
+ if (ret_all) {
+ tmp = realloc(all, (count + 1) * sizeof(*tmp));
+ if (!tmp)
+ goto error;
+ all = tmp;
+ all[count] = devent;
+ }
+ count++;
+ }
+ line = next + 1;
+ } while (next);
+
+ free(content);
+ if (ret_all)
+ *ret_all = all;
+ return count;
+
+error:
+ free(content);
+ free(all);
+ return -1;
+}
+
+/**
+ * tracefs_dynevent_list_free - Deletes an array of pointers to dynamic event contexts
+ * @events: An array of pointers to dynamic event contexts. The last element of the array
+ * must be a NULL pointer.
+ */
+void tracefs_dynevent_list_free(struct tracefs_dynevent **events)
+{
+ int i;
+
+ if (!events)
+ return;
+
+ for (i = 0; events[i]; i++)
+ tracefs_dynevent_free(events[i]);
+
+ free(events);
+}
+
+/**
+ * tracefs_dynevent_get_all - return an array of pointers to dynamic events of given types
+ * @types: Dynamic event type, or bitmask of dynamic event types. If 0 is passed, all types
+ * are considered.
+ * @system: Get events from that system only. If @system is NULL, events from all systems
+ * are returned.
+ *
+ * Returns an array of pointers to dynamic events of given types that exist in the system.
+ * The array must be freed with tracefs_dynevent_list_free(). If there are no events a NULL
+ * pointer is returned.
+ */
+struct tracefs_dynevent **
+tracefs_dynevent_get_all(unsigned int types, const char *system)
+{
+ struct tracefs_dynevent **events, **tmp, **all_events = NULL;
+ int count, all = 0;
+ int i;
+
+ for (i = 1; i < TRACEFS_DYNEVENT_MAX; i <<= 1) {
+ if (types) {
+ if (i > types)
+ break;
+ if (!(types & i))
+ continue;
+ }
+ count = get_all_dynevents(i, system, &events);
+ if (count > 0) {
+ tmp = realloc(all_events, (all + count + 1) * sizeof(*tmp));
+ if (!tmp)
+ goto error;
+ all_events = tmp;
+ memcpy(all_events + all, events, count * sizeof(*events));
+ all += count;
+ /* Add a NULL pointer at the end */
+ all_events[all] = NULL;
+ }
+ }
+
+ return all_events;
+
+error:
+ if (all_events) {
+ for (i = 0; i < all; i++)
+ free(all_events[i]);
+ free(all_events);
+ }
+ return NULL;
+}
+
+/**
+ * tracefs_dynevent_destroy_all - removes all dynamic events of given types from the system
+ * @types: Dynamic event type, or bitmask of dynamic event types. If 0 is passed, all types
+ * are considered.
+ * @force: Will attempt to disable all events before removing them.
+ *
+ * Will remove all dynamic events of the given types from the system. If there are any enabled
+ * events, and @force is not set, then the removal of these will fail. If @force is set, then
+ * it will attempt to disable all the events in all instances before removing them.
+ *
+ * Returns zero if all requested events are removed successfully, or -1 if some of them are not
+ * removed.
+ */
+int tracefs_dynevent_destroy_all(unsigned int types, bool force)
+{
+ struct tracefs_dynevent **all;
+ int ret = 0;
+ int i;
+
+ all = tracefs_dynevent_get_all(types, NULL);
+ if (!all)
+ return 0;
+
+ for (i = 0; all[i]; i++) {
+ if (tracefs_dynevent_destroy(all[i], force))
+ ret = -1;
+ }
+
+ tracefs_dynevent_list_free(all);
+
+ return ret;
+}
+
+/**
+ * dynevent_get_count - Count dynamic events of given types and system
+ * @types: Dynamic event type, or bitmask of dynamic event types. If 0 is passed, all types
+ * are considered.
+ * @system: Count events from that system only. If @system is NULL, events from all systems
+ * are counted.
+ *
+ * Return the count of requested dynamic events
+ */
+__hidden int dynevent_get_count(unsigned int types, const char *system)
+{
+ int count, all = 0;
+ int i;
+
+ for (i = 1; i < TRACEFS_DYNEVENT_MAX; i <<= 1) {
+ if (types) {
+ if (i > types)
+ break;
+ if (!(types & i))
+ continue;
+ }
+ count = get_all_dynevents(i, system, NULL);
+ if (count > 0)
+ all += count;
+ }
+
+ return all;
+}
+
+/**
+ * tracefs_dynevent_info - return details of a dynamic event
+ * @dynevent: A dynamic event context, describing given dynamic event.
+ * @group: return, group in which the dynamic event is configured
+ * @event: return, name of the dynamic event
+ * @prefix: return, prefix string of the dynamic event
+ * @addr: return, the function and offset (or address) of the dynamic event
+ * @format: return, the format string of the dynamic event
+ *
+ * Returns the type of the dynamic event, or TRACEFS_DYNEVENT_UNKNOWN in case of an error.
+ * Any of the @group, @event, @prefix, @addr and @format parameters are optional.
+ * If a valid pointer is passed, in case of success - a string is allocated and returned.
+ * These strings must be freed with free().
+ */
+
+enum tracefs_dynevent_type
+tracefs_dynevent_info(struct tracefs_dynevent *dynevent, char **system,
+ char **event, char **prefix, char **addr, char **format)
+{
+ char **lv[] = { system, event, prefix, addr, format };
+ char **rv[] = { &dynevent->system, &dynevent->event, &dynevent->prefix,
+ &dynevent->address, &dynevent->format };
+ int i;
+
+ if (!dynevent)
+ return TRACEFS_DYNEVENT_UNKNOWN;
+
+ for (i = 0; i < ARRAY_SIZE(lv); i++) {
+ if (lv[i]) {
+ if (*rv[i]) {
+ *lv[i] = strdup(*rv[i]);
+ if (!*lv[i])
+ goto error;
+ } else {
+ *lv[i] = NULL;
+ }
+ }
+ }
+
+ return dynevent->type;
+
+error:
+ for (i--; i >= 0; i--) {
+ if (lv[i])
+ free(*lv[i]);
+ }
+
+ return TRACEFS_DYNEVENT_UNKNOWN;
+}
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* Re: [PATCH v6 01/12] libtracefs: New APIs for dynamic events
2021-11-08 8:03 ` [PATCH v6 01/12] libtracefs: New APIs for dynamic events Tzvetomir Stoyanov (VMware)
@ 2021-11-11 22:33 ` Steven Rostedt
2021-11-12 5:04 ` Tzvetomir Stoyanov
0 siblings, 1 reply; 17+ messages in thread
From: Steven Rostedt @ 2021-11-11 22:33 UTC (permalink / raw)
To: Tzvetomir Stoyanov (VMware); +Cc: y.karadz, linux-trace-devel
After applying these patches, I tested sqlhist and it's broken.
What I do is:
(as root)
# mkdir /tmp/tracing
# cp -a /sys/kernel/tracing/events /tmp/tracing
(as my user)
$ ./sqlhist -t /tmp/tracing/ -n waking 'select start.pid,
(end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as delta from sched_waking as start join sched_switch as end on start.pid = end.next_pid'
Which prints nothing, but before applying the patches, I would have this:
echo 'waking s32 pid; u64 delta;' > /sys/kernel/tracing/synthetic_events
echo 'hist:keys=pid:__arg_15772_1=pid,__arg_15772_2=common_timestamp.usecs' > /sys/kernel/tracing/events/sched/sched_waking/trigger
echo 'hist:keys=next_pid:pid=$__arg_15772_1,delta=common_timestamp.usecs-$__arg_15772_2:onmatch(sched.sched_waking).trace(waking,$pid,$delta)' > /sys/kernel/tracing/events/sched/sched_switch/trigger
Debugging it, I found that it's due to this change.
On Mon, 8 Nov 2021 10:03:53 +0200
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:
> +static void init_devent_desc(void)
> +{
> + int i;
> +
> + BUILD_BUG_ON(ARRAY_SIZE(dynevents) != EVENT_INDEX(TRACEFS_DYNEVENT_MAX));
> +
> + /* Use ftrace dynamic_events, if available */
> + if (tracefs_file_exists(NULL, DYNEVENTS_EVENTS)) {
// fails due to permission denied.
> + for (i = 0; i < EVENT_INDEX(TRACEFS_DYNEVENT_MAX); i++)
> + dynevents[i].file = DYNEVENTS_EVENTS;
> + return;
> + }
> +
> + if (tracefs_file_exists(NULL, KPROBE_EVENTS)) {
// fails due to permission denied.
> + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_KPROBE)].file = KPROBE_EVENTS;
> + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_KRETPROBE)].file = KPROBE_EVENTS;
> + }
> + if (tracefs_file_exists(NULL, UPROBE_EVENTS)) {
// fails due to permission denied.
> + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_UPROBE)].file = UPROBE_EVENTS;
> + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_URETPROBE)].file = UPROBE_EVENTS;
> + }
> + if (tracefs_file_exists(NULL, SYNTH_EVENTS)) {
// fails due to permission denied.
> + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].file = SYNTH_EVENTS;
> + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].prefix = "";
> + }
> +}
> +
> +static struct dyn_events_desc *get_devent_desc(enum tracefs_dynevent_type type)
> +{
> +
> + static bool init;
> +
> + if (type >= TRACEFS_DYNEVENT_MAX)
> + return NULL;
> +
> + if (!init) {
> + init_devent_desc();
> + init = true;
> + }
> +
> + return &dynevents[EVENT_INDEX(type)];
> +}
> +
> +/**
> + * dynevent_alloc - Allocate new dynamic event
> + * @type: Type of the dynamic event
> + * @system: The system name (NULL for the default dynamic)
> + * @event: Name of the event
> + * @addr: The function and offset (or address) to insert the probe
> + * @format: The format string to define the probe.
> + *
> + * Allocate a dynamic event context that will be in the @system group
> + * (or dynamic if @system is NULL). Have the name of @event and
> + * will be associated to @addr, if applicable for that event type
> + * (function name, with or without offset, or a address). And the @format will
> + * define the format of the kprobe.
> + * The dynamic event is not created in the system.
> + *
> + * Return a pointer to a dynamic event context on success, or NULL on error.
> + * The returned pointer must be freed with tracefs_dynevent_free()
> + *
> + * errno will be set to EINVAL if event is NULL.
> + */
> +__hidden struct tracefs_dynevent *
> +dynevent_alloc(enum tracefs_dynevent_type type, const char *system,
> + const char *event, const char *address, const char *format)
> +{
> + struct tracefs_dynevent *devent;
> + struct dyn_events_desc *desc;
> +
> + if (!event) {
> + errno = EINVAL;
> + return NULL;
> + }
> +
> + desc = get_devent_desc(type);
desc->file is NULL.
> + if (!desc || !desc->file) {
> + errno = ENOTSUP;
Returns an error, when it use to work.
> + return NULL;
> + }
-- Steve
^ permalink raw reply [flat|nested] 17+ messages in thread* Re: [PATCH v6 01/12] libtracefs: New APIs for dynamic events
2021-11-11 22:33 ` Steven Rostedt
@ 2021-11-12 5:04 ` Tzvetomir Stoyanov
2021-11-12 12:35 ` Steven Rostedt
0 siblings, 1 reply; 17+ messages in thread
From: Tzvetomir Stoyanov @ 2021-11-12 5:04 UTC (permalink / raw)
To: Steven Rostedt; +Cc: Yordan Karadzhov, Linux Trace Devel
Hi Steven,
On Fri, Nov 12, 2021 at 12:33 AM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> After applying these patches, I tested sqlhist and it's broken.
>
> What I do is:
>
> (as root)
> # mkdir /tmp/tracing
> # cp -a /sys/kernel/tracing/events /tmp/tracing
>
> (as my user)
> $ ./sqlhist -t /tmp/tracing/ -n waking 'select start.pid,
> (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as delta from sched_waking as start join sched_switch as end on start.pid = end.next_pid'
>
> Which prints nothing, but before applying the patches, I would have this:
>
> echo 'waking s32 pid; u64 delta;' > /sys/kernel/tracing/synthetic_events
> echo 'hist:keys=pid:__arg_15772_1=pid,__arg_15772_2=common_timestamp.usecs' > /sys/kernel/tracing/events/sched/sched_waking/trigger
> echo 'hist:keys=next_pid:pid=$__arg_15772_1,delta=common_timestamp.usecs-$__arg_15772_2:onmatch(sched.sched_waking).trace(waking,$pid,$delta)' > /sys/kernel/tracing/events/sched/sched_switch/trigger
>
> Debugging it, I found that it's due to this change.
>
I totally missed the custom trace dir use case. The dynevents APIs
should be extended with additional parameter, to handle that use case.
I see two ways to do this:
1. Passing a tracefs_instance* parameter to those APIs. This can be
NULL for top instance in default tracing directory, or allocated with:
tracefs_instance_alloc("/tmp/tracing/", NULL) - for the instance
in a custom tracing directory.
This approach adds flexibility to work with any non default
instance. It also resolves that question with the instance needed by
the histograms configuration.
2. Passing a string parameter with custom trace directory path, or
NULL for default system trace directory.
Those APIs should be extended with that additional parameter:
tracefs_dynevent_get_all()
tracefs_dynevent_destroy_all()
tracefs_kprobe_alloc()
tracefs_kretprobe_alloc()
tracefs_kprobe_raw()
tracefs_kretprobe_raw()
tracefs_synth_alloc()
tracefs_sql()
>
> On Mon, 8 Nov 2021 10:03:53 +0200
> "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:
>
> > +static void init_devent_desc(void)
> > +{
> > + int i;
> > +
> > + BUILD_BUG_ON(ARRAY_SIZE(dynevents) != EVENT_INDEX(TRACEFS_DYNEVENT_MAX));
> > +
> > + /* Use ftrace dynamic_events, if available */
> > + if (tracefs_file_exists(NULL, DYNEVENTS_EVENTS)) {
>
> // fails due to permission denied.
>
> > + for (i = 0; i < EVENT_INDEX(TRACEFS_DYNEVENT_MAX); i++)
> > + dynevents[i].file = DYNEVENTS_EVENTS;
> > + return;
> > + }
> > +
> > + if (tracefs_file_exists(NULL, KPROBE_EVENTS)) {
>
> // fails due to permission denied.
>
> > + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_KPROBE)].file = KPROBE_EVENTS;
> > + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_KRETPROBE)].file = KPROBE_EVENTS;
> > + }
> > + if (tracefs_file_exists(NULL, UPROBE_EVENTS)) {
>
> // fails due to permission denied.
>
> > + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_UPROBE)].file = UPROBE_EVENTS;
> > + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_URETPROBE)].file = UPROBE_EVENTS;
> > + }
> > + if (tracefs_file_exists(NULL, SYNTH_EVENTS)) {
>
> // fails due to permission denied.
>
> > + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].file = SYNTH_EVENTS;
> > + dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].prefix = "";
> > + }
> > +}
> > +
> > +static struct dyn_events_desc *get_devent_desc(enum tracefs_dynevent_type type)
> > +{
> > +
> > + static bool init;
> > +
> > + if (type >= TRACEFS_DYNEVENT_MAX)
> > + return NULL;
> > +
> > + if (!init) {
> > + init_devent_desc();
> > + init = true;
> > + }
> > +
> > + return &dynevents[EVENT_INDEX(type)];
> > +}
> > +
> > +/**
> > + * dynevent_alloc - Allocate new dynamic event
> > + * @type: Type of the dynamic event
> > + * @system: The system name (NULL for the default dynamic)
> > + * @event: Name of the event
> > + * @addr: The function and offset (or address) to insert the probe
> > + * @format: The format string to define the probe.
> > + *
> > + * Allocate a dynamic event context that will be in the @system group
> > + * (or dynamic if @system is NULL). Have the name of @event and
> > + * will be associated to @addr, if applicable for that event type
> > + * (function name, with or without offset, or a address). And the @format will
> > + * define the format of the kprobe.
> > + * The dynamic event is not created in the system.
> > + *
> > + * Return a pointer to a dynamic event context on success, or NULL on error.
> > + * The returned pointer must be freed with tracefs_dynevent_free()
> > + *
> > + * errno will be set to EINVAL if event is NULL.
> > + */
> > +__hidden struct tracefs_dynevent *
> > +dynevent_alloc(enum tracefs_dynevent_type type, const char *system,
> > + const char *event, const char *address, const char *format)
> > +{
> > + struct tracefs_dynevent *devent;
> > + struct dyn_events_desc *desc;
> > +
> > + if (!event) {
> > + errno = EINVAL;
> > + return NULL;
> > + }
> > +
> > + desc = get_devent_desc(type);
>
> desc->file is NULL.
>
> > + if (!desc || !desc->file) {
> > + errno = ENOTSUP;
>
> Returns an error, when it use to work.
>
> > + return NULL;
> > + }
>
> -- Steve
--
Tzvetomir (Ceco) Stoyanov
VMware Open Source Technology Center
^ permalink raw reply [flat|nested] 17+ messages in thread* Re: [PATCH v6 01/12] libtracefs: New APIs for dynamic events
2021-11-12 5:04 ` Tzvetomir Stoyanov
@ 2021-11-12 12:35 ` Steven Rostedt
0 siblings, 0 replies; 17+ messages in thread
From: Steven Rostedt @ 2021-11-12 12:35 UTC (permalink / raw)
To: Tzvetomir Stoyanov; +Cc: Yordan Karadzhov, Linux Trace Devel
On Fri, 12 Nov 2021 07:04:36 +0200
Tzvetomir Stoyanov <tz.stoyanov@gmail.com> wrote:
> Hi Steven,
>
> On Fri, Nov 12, 2021 at 12:33 AM Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> > After applying these patches, I tested sqlhist and it's broken.
> >
> > What I do is:
> >
> > (as root)
> > # mkdir /tmp/tracing
> > # cp -a /sys/kernel/tracing/events /tmp/tracing
> >
> > (as my user)
> > $ ./sqlhist -t /tmp/tracing/ -n waking 'select start.pid,
> > (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as delta from sched_waking as start join sched_switch as end on start.pid = end.next_pid'
> >
> > Which prints nothing, but before applying the patches, I would have this:
> >
> > echo 'waking s32 pid; u64 delta;' > /sys/kernel/tracing/synthetic_events
> > echo 'hist:keys=pid:__arg_15772_1=pid,__arg_15772_2=common_timestamp.usecs' > /sys/kernel/tracing/events/sched/sched_waking/trigger
> > echo 'hist:keys=next_pid:pid=$__arg_15772_1,delta=common_timestamp.usecs-$__arg_15772_2:onmatch(sched.sched_waking).trace(waking,$pid,$delta)' > /sys/kernel/tracing/events/sched/sched_switch/trigger
> >
> > Debugging it, I found that it's due to this change.
> >
>
> I totally missed the custom trace dir use case. The dynevents APIs
> should be extended with additional parameter, to handle that use case.
> I see two ways to do this:
> 1. Passing a tracefs_instance* parameter to those APIs. This can be
> NULL for top instance in default tracing directory, or allocated with:
> tracefs_instance_alloc("/tmp/tracing/", NULL) - for the instance
> in a custom tracing directory.
> This approach adds flexibility to work with any non default
> instance. It also resolves that question with the instance needed by
> the histograms configuration.
> 2. Passing a string parameter with custom trace directory path, or
> NULL for default system trace directory.
>
> Those APIs should be extended with that additional parameter:
No, it does not. This is an internal issue, let's not burden the users with
extra information they need to manage.
The problem goes away with the following patch:
diff --git a/src/tracefs-dynevents.c b/src/tracefs-dynevents.c
index f525e8d..f2a6c8d 100644
--- a/src/tracefs-dynevents.c
+++ b/src/tracefs-dynevents.c
@@ -41,16 +41,14 @@ struct dyn_events_desc {
int (*parse)(struct dyn_events_desc *desc, const char *group,
char *line, struct tracefs_dynevent **ret_dyn);
} dynevents[] = {
- {TRACEFS_DYNEVENT_KPROBE, NULL, "p", dyn_generic_del, dyn_generic_parse},
- {TRACEFS_DYNEVENT_KRETPROBE, NULL, "r", dyn_generic_del, dyn_generic_parse},
- {TRACEFS_DYNEVENT_UPROBE, NULL, "p", dyn_generic_del, dyn_generic_parse},
- {TRACEFS_DYNEVENT_URETPROBE, NULL, "r", dyn_generic_del, dyn_generic_parse},
- {TRACEFS_DYNEVENT_EPROBE, NULL, "e", dyn_generic_del, dyn_generic_parse},
- {TRACEFS_DYNEVENT_SYNTH, NULL, "s", dyn_synth_del, dyn_synth_parse},
+ {TRACEFS_DYNEVENT_KPROBE, KPROBE_EVENTS, "p", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_KRETPROBE, KPROBE_EVENTS, "r", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_UPROBE, UPROBE_EVENTS, "p", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_URETPROBE, UPROBE_EVENTS, "r", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_EPROBE, SYNTH_EVENTS, "e", dyn_generic_del, dyn_generic_parse},
+ {TRACEFS_DYNEVENT_SYNTH, "", "s", dyn_synth_del, dyn_synth_parse},
};
-
-
static int dyn_generic_del(struct dyn_events_desc *desc, struct tracefs_dynevent *dyn)
{
char *str;
@@ -282,19 +280,6 @@ static void init_devent_desc(void)
dynevents[i].file = DYNEVENTS_EVENTS;
return;
}
-
- if (tracefs_file_exists(NULL, KPROBE_EVENTS)) {
- dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_KPROBE)].file = KPROBE_EVENTS;
- dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_KRETPROBE)].file = KPROBE_EVENTS;
- }
- if (tracefs_file_exists(NULL, UPROBE_EVENTS)) {
- dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_UPROBE)].file = UPROBE_EVENTS;
- dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_URETPROBE)].file = UPROBE_EVENTS;
- }
- if (tracefs_file_exists(NULL, SYNTH_EVENTS)) {
- dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].file = SYNTH_EVENTS;
- dynevents[EVENT_INDEX(TRACEFS_DYNEVENT_SYNTH)].prefix = "";
- }
}
static struct dyn_events_desc *get_devent_desc(enum tracefs_dynevent_type type)
Let the if the files do not exist, then let the failure happen when the the
user tries to create the event in the system. The external directory is
only for reading, not for creating.
-- Steve
^ permalink raw reply related [flat|nested] 17+ messages in thread
* [PATCH v6 02/12] libtracefs: New APIs for kprobe allocation
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
2021-11-08 8:03 ` [PATCH v6 01/12] libtracefs: New APIs for dynamic events Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:03 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:03 ` [PATCH v6 03/12] libtracefs: Remove redundant kprobes APIs Tzvetomir Stoyanov (VMware)
` (9 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:03 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
In order to be consistent with the other APIs, new APIs for kprobe
allocation are introduced:
tracefs_kprobe_alloc();
tracefs_kretprobe_alloc();
These APIs allocate new kpobe dynamic event, that can be used with
tracefs_dynevent_... set of APIs.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
include/tracefs.h | 5 ++
src/tracefs-kprobes.c | 109 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 114 insertions(+)
diff --git a/include/tracefs.h b/include/tracefs.h
index eceb1f5..dfd9b51 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -267,6 +267,11 @@ enum tracefs_kprobe_type {
TRACEFS_KRETPROBE,
};
+struct tracefs_dynevent *
+tracefs_kprobe_alloc(const char *system, const char *event, const char *addr, const char *format);
+struct tracefs_dynevent *
+tracefs_kretprobe_alloc(const char *system, const char *event,
+ const char *addr, const char *format, unsigned int max);
int tracefs_kprobe_raw(const char *system, const char *event,
const char *addr, const char *format);
int tracefs_kretprobe_raw(const char *system, const char *event,
diff --git a/src/tracefs-kprobes.c b/src/tracefs-kprobes.c
index 6fdd8f9..b9aeb9d 100644
--- a/src/tracefs-kprobes.c
+++ b/src/tracefs-kprobes.c
@@ -20,6 +20,115 @@
#define KPROBE_EVENTS "kprobe_events"
#define KPROBE_DEFAULT_GROUP "kprobes"
+static struct tracefs_dynevent *
+kprobe_alloc(enum tracefs_dynevent_type type, const char *system, const char *event,
+ const char *addr, const char *format)
+{
+ struct tracefs_dynevent *kp;
+ const char *sys = system;
+ const char *ename = event;
+ char *tmp;
+
+ if (!addr) {
+ errno = EBADMSG;
+ return NULL;
+ }
+ if (!sys)
+ sys = KPROBE_DEFAULT_GROUP;
+
+ if (!event) {
+ ename = strdup(addr);
+ if (!ename)
+ return NULL;
+ tmp = strchr(ename, ':');
+ if (tmp)
+ *tmp = '\0';
+ }
+
+ kp = dynevent_alloc(type, sys, ename, addr, format);
+ if (!event)
+ free((char *)ename);
+
+ return kp;
+}
+
+/**
+ * tracefs_kprobe_alloc - Allocate new kprobe
+ * @system: The system name (NULL for the default kprobes)
+ * @event: The event to create (NULL to use @addr for the event)
+ * @addr: The function and offset (or address) to insert the probe
+ * @format: The format string to define the probe.
+ *
+ * Allocate a kprobe context that will be in the @system group (or kprobes if
+ * @system is NULL). Have the name of @event (or @addr if @event is NULL). Will
+ * be inserted to @addr (function name, with or without offset, or a address).
+ * And the @format will define the format of the kprobe.
+ *
+ * See the Linux documentation file under:
+ * Documentation/trace/kprobetrace.rst
+ *
+ * The kprobe is not created in the system.
+ *
+ * Return a pointer to a kprobe context on success, or NULL on error.
+ * The returned pointer must be freed with tracefs_dynevent_free()
+ *
+ * errno will be set to EBADMSG if addr is NULL.
+ */
+struct tracefs_dynevent *
+tracefs_kprobe_alloc(const char *system, const char *event, const char *addr, const char *format)
+
+{
+ return kprobe_alloc(TRACEFS_DYNEVENT_KPROBE, system, event, addr, format);
+}
+
+/**
+ * tracefs_kretprobe_alloc - Allocate new kretprobe
+ * @system: The system name (NULL for the default kprobes)
+ * @event: The event to create (NULL to use @addr for the event)
+ * @addr: The function and offset (or address) to insert the retprobe
+ * @format: The format string to define the retprobe.
+ * @max: Maximum number of instances of the specified function that
+ * can be probed simultaneously, or 0 for the default value.
+ *
+ * Allocate a kretprobe that will be in the @system group (or kprobes if
+ * @system is NULL). Have the name of @event (or @addr if @event is
+ * NULL). Will be inserted to @addr (function name, with or without
+ * offset, or a address). And the @format will define the raw format
+ * of the kprobe. See the Linux documentation file under:
+ * Documentation/trace/kprobetrace.rst
+ * The kretprobe is not created in the system.
+ *
+ * Return a pointer to a kprobe context on success, or NULL on error.
+ * The returned pointer must be freed with tracefs_dynevent_free()
+ *
+ * errno will be set to EBADMSG if addr is NULL.
+ */
+struct tracefs_dynevent *
+tracefs_kretprobe_alloc(const char *system, const char *event,
+ const char *addr, const char *format, unsigned int max)
+{
+ struct tracefs_dynevent *kp;
+ int ret;
+
+ kp = kprobe_alloc(TRACEFS_DYNEVENT_KRETPROBE, system, event, addr, format);
+ if (!kp)
+ return NULL;
+
+ if (!max)
+ return kp;
+
+ free(kp->prefix);
+ kp->prefix = NULL;
+ ret = asprintf(&kp->prefix, "r%d:", max);
+ if (ret < 0)
+ goto error;
+
+ return kp;
+error:
+ tracefs_dynevent_free(kp);
+ return NULL;
+}
+
static int insert_kprobe(const char *type, const char *system,
const char *event, const char *addr,
const char *format)
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 03/12] libtracefs: Remove redundant kprobes APIs
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
2021-11-08 8:03 ` [PATCH v6 01/12] libtracefs: New APIs for dynamic events Tzvetomir Stoyanov (VMware)
2021-11-08 8:03 ` [PATCH v6 02/12] libtracefs: New APIs for kprobe allocation Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:03 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:03 ` [PATCH v6 04/12] libtracefs: Reimplement kprobe raw APIs Tzvetomir Stoyanov (VMware)
` (8 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:03 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
The newly introduced set of APIs tracefs_dynevent_...() can be used to
manage kprobes. These legacy APIs are removed as redundant:
tracefs_kprobe_clear_all();
tracefs_kprobe_clear_probe();
tracefs_get_kprobes()
tracefs_kprobe_info()
There is one functionality, missing in the new clear API - clearing all
dynamic events from specific system only. If this is needed,
tracefs_dynevent_destroy() can be extended with that use case.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
include/tracefs.h | 11 --
src/tracefs-kprobes.c | 370 ------------------------------------------
2 files changed, 381 deletions(-)
diff --git a/include/tracefs.h b/include/tracefs.h
index dfd9b51..25d9e9a 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -261,12 +261,6 @@ enum tracefs_dynevent_type
tracefs_dynevent_info(struct tracefs_dynevent *dynevent, char **system,
char **event, char **prefix, char **addr, char **format);
-enum tracefs_kprobe_type {
- TRACEFS_ALL_KPROBES,
- TRACEFS_KPROBE,
- TRACEFS_KRETPROBE,
-};
-
struct tracefs_dynevent *
tracefs_kprobe_alloc(const char *system, const char *event, const char *addr, const char *format);
struct tracefs_dynevent *
@@ -276,11 +270,6 @@ int tracefs_kprobe_raw(const char *system, const char *event,
const char *addr, const char *format);
int tracefs_kretprobe_raw(const char *system, const char *event,
const char *addr, const char *format);
-char **tracefs_get_kprobes(enum tracefs_kprobe_type type);
-enum tracefs_kprobe_type tracefs_kprobe_info(const char *group, const char *event,
- char **type, char **addr, char **format);
-int tracefs_kprobe_clear_all(bool force);
-int tracefs_kprobe_clear_probe(const char *system, const char *event, bool force);
enum tracefs_hist_key_type {
TRACEFS_HIST_KEY_NORMAL = 0,
diff --git a/src/tracefs-kprobes.c b/src/tracefs-kprobes.c
index b9aeb9d..3f46b8d 100644
--- a/src/tracefs-kprobes.c
+++ b/src/tracefs-kprobes.c
@@ -213,373 +213,3 @@ int tracefs_kretprobe_raw(const char *system, const char *event,
{
return insert_kprobe("r", system, event, addr, format);
}
-
-/*
- * Helper function to parse kprobes.
- * @content: The content of kprobe_events on the first iteration.
- * NULL on next iterations.
- * @saveptr: Same as saveptr for strtok_r
- * @type: Where to store the type (before ':')
- * @system: Store the system of the kprobe (NULL to have event contain
- * both system and event, as in "kprobes/myprobe").
- * @event: Where to store the event.
- * @addr: Where to store the addr (may be NULL to ignore)
- * @format: Where to store the format (may be NULL to ignore)
- */
-static int parse_kprobe(char *content, char **saveptr,
- char **type, char **system, char **event,
- char **addr, char **format)
-{
- char *p;
-
- p = strtok_r(content, ":", saveptr);
- if (!p)
- return 1; /* eof */
- *type = p;
-
- if (system) {
- p = strtok_r(NULL, "/", saveptr);
- if (!p)
- return -1;
- *system = p;
- }
-
- p = strtok_r(NULL, " ", saveptr);
- if (!p)
- return -1;
- *event = p;
-
- if (addr || format) {
- p = strtok_r(NULL, " ", saveptr);
- if (!p)
- return -1;
- if (addr)
- *addr = p;
- }
-
- p = strtok_r(NULL, "\n", saveptr);
- if (!p)
- return -1;
- if (format)
- *format = p;
-
- return 0;
-}
-
-/**
- * tracefs_get_kprobes - return a list kprobes (by group/event name)
- * @type: The type of kprobes to return.
- *
- * If @type is TRACEFS_ALL_KPROBES all kprobes in the kprobe_events
- * are returned. Otherwise if it is TRACEFS_KPROBE, then only
- * normal kprobes (p:) are returned, or if type is TRACEFS_KRETPROBE
- * then only kretprobes (r:) are returned.
- *
- * Returns a list of strings that contain the kprobes that exist
- * in the kprobe_events files. The strings returned are in the
- * "group/event" format.
- * The list must be freed with tracefs_list_free().
- * If there are no kprobes, a list is still returned, but it contains
- * only a NULL pointer.
- * On error, NULL is returned.
- */
-char **tracefs_get_kprobes(enum tracefs_kprobe_type type)
-{
- char **list = NULL;
- char *content;
- char *saveptr;
- char *event;
- char *ktype;
- int ret;
-
- errno = 0;
- content = tracefs_instance_file_read(NULL, KPROBE_EVENTS, NULL);
- if (!content) {
- if (errno)
- return NULL;
- /* content is NULL on empty file, return an empty list */
- return trace_list_create_empty();
- }
-
- ret = parse_kprobe(content, &saveptr, &ktype, NULL, &event, NULL, NULL);
-
- while (!ret) {
- char **tmp;
-
- if (type != TRACEFS_ALL_KPROBES) {
- switch (*ktype) {
- case 'p':
- if (type != TRACEFS_KPROBE)
- goto next;
- break;
- case 'r':
- if (type != TRACEFS_KRETPROBE)
- goto next;
- break;
- default:
- goto next;
- }
- }
-
- tmp = tracefs_list_add(list, event);
- if (!tmp)
- goto fail;
- list = tmp;
- next:
- ret = parse_kprobe(NULL, &saveptr, &ktype, NULL, &event, NULL, NULL);
- }
-
- if (!list)
- list = trace_list_create_empty();
- out:
- free(content);
- return list;
- fail:
- tracefs_list_free(list);
- list = NULL;
- goto out;
-}
-
-/**
- * tracefs_kprobe_info - return the type of kprobe specified.
- * @group: The group the kprobe is in (NULL for the default "kprobes")
- * @event: The name of the kprobe to find.
- * @type: String to return kprobe type (before ':') NULL to ignore.
- * @addr: String to return address kprobe is attached to. NULL to ignore.
- * @format: String to return kprobe format. NULL to ignore.
- *
- * If @type, @addr, or @format is non NULL, then the returned string
- * must be freed with free(). They will also be set to NULL, and
- * even on error, they may contain strings to be freed. If they are
- * not NULL, then they still need to be freed.
- *
- * Returns TRACEFS_ALL_KPROBES if an error occurs or the kprobe is not found,
- * or the probe is of an unknown type.
- * TRACEFS_KPROBE if the type of kprobe found is a normal kprobe.
- * TRACEFS_KRETPROBE if the type of kprobe found is a kretprobe.
- */
-enum tracefs_kprobe_type tracefs_kprobe_info(const char *group, const char *event,
- char **type, char **addr, char **format)
-{
- enum tracefs_kprobe_type rtype = TRACEFS_ALL_KPROBES;
- char *saveptr;
- char *content;
- char *system;
- char *probe;
- char *ktype;
- char *kaddr;
- char *kfmt;
- int ret;
-
- if (!group)
- group = KPROBE_DEFAULT_GROUP;
-
- if (type)
- *type = NULL;
- if (addr)
- *addr = NULL;
- if (format)
- *format = NULL;
-
- content = tracefs_instance_file_read(NULL, KPROBE_EVENTS, NULL);
- if (!content)
- return rtype;
-
- ret = parse_kprobe(content, &saveptr, &ktype, &system, &probe,
- &kaddr, &kfmt);
-
- while (!ret) {
-
- if (!strcmp(system, group) && !strcmp(probe, event)) {
- if (type)
- *type = strdup(ktype);
- if (addr)
- *addr = strdup(kaddr);
- if (format)
- *format = strdup(kfmt);
-
- switch (*ktype) {
- case 'p': rtype = TRACEFS_KPROBE; break;
- case 'r': rtype = TRACEFS_KRETPROBE; break;
- }
- break;
- }
- ret = parse_kprobe(NULL, &saveptr, &ktype, &system, &probe,
- &kaddr, &kfmt);
- }
- free(content);
- return rtype;
-}
-
-static void disable_events(const char *system, const char *event,
- char **list)
-{
- struct tracefs_instance *instance;
- int i;
-
- /*
- * Note, this will not fail even on error.
- * That is because even if something fails, it may still
- * work enough to clear the kprobes. If that's the case
- * the clearing after the loop will succeed and the function
- * is a success, even though other parts had failed. If
- * one of the kprobe events is enabled in one of the
- * instances that fail, then the clearing will fail too
- * and the function will return an error.
- */
-
- tracefs_event_disable(NULL, system, event);
- /* No need to test results */
-
- if (!list)
- return;
-
- for (i = 0; list[i]; i++) {
- instance = tracefs_instance_alloc(NULL, list[i]);
- /* If this fails, try the next one */
- if (!instance)
- continue;
- tracefs_event_disable(instance, system, event);
- tracefs_instance_free(instance);
- }
- return;
-}
-
-static int clear_kprobe(const char *system, const char *event)
-{
- /* '-' + ':' + '/' + '\n' + '\0' = 5 bytes */
- int len = strlen(system) + strlen(event) + 5;
- char content[len];
-
- sprintf(content, "-:%s/%s", system, event);
- return tracefs_instance_file_append(NULL, KPROBE_EVENTS, content);
-}
-
-static int kprobe_clear_probes(const char *group, bool force)
-{
- char **instance_list;
- char **kprobe_list;
- char *saveptr;
- char *system;
- char *kprobe;
- char *event;
- int ret;
- int i;
-
- kprobe_list = tracefs_get_kprobes(TRACEFS_ALL_KPROBES);
- if (!kprobe_list)
- return -1;
-
- instance_list = tracefs_instances(NULL);
- /*
- * Even if the above failed and instance_list is NULL,
- * keep going, as the enabled event may simply be in the
- * top level.
- */
-
- /*
- * If a system is defined, the default is to pass unless
- * an event fails to be removed. If a system is not defined,
- * the default is to fail, unless all are removed.
- */
- ret = group ? 0 : -1;
-
- for (i = 0; kprobe_list[i]; i++) {
- kprobe = kprobe_list[i];
-
- system = strtok_r(kprobe, "/", &saveptr);
- if (!system)
- goto out;
-
- event = strtok_r(NULL," ", &saveptr);
- if (!event)
- goto out;
-
- /* Skip if this does not match a given system */
- if (group && strcmp(system, group) != 0)
- continue;
-
- if (force)
- disable_events(system, event, instance_list);
-
- if (group) {
- ret = clear_kprobe(system, event);
- if (ret < 0)
- goto out;
- } else {
- ret = tracefs_instance_file_clear(NULL, KPROBE_EVENTS);
- /* On success stop the loop */
- if (!ret)
- goto out;
- }
-
- /* Set the default for whether a system is defined or not */
- ret = group ? 0 : -1;
- }
- out:
- tracefs_list_free(instance_list);
- tracefs_list_free(kprobe_list);
- return ret;
-}
-
-/**
- * tracefs_kprobe_clear_all - clear kprobe events
- * @force: Will attempt to disable all kprobe events and clear them
- *
- * Will remove all defined kprobe events. If any of them are enabled,
- * and @force is not set, then it will error with -1 and errno to be
- * EBUSY. If @force is set, then it will attempt to disable all the kprobe
- * events in all instances, and try again.
- *
- * Returns zero on success, -1 otherwise.
- */
-int tracefs_kprobe_clear_all(bool force)
-{
- if (tracefs_instance_file_clear(NULL, KPROBE_EVENTS) == 0)
- return 0;
-
- if (!force)
- return -1;
-
- /* Attempt to disable all kprobe events */
- return kprobe_clear_probes(NULL, force);
-}
-
-/**
- * tracefs_kprobe_clear_all - clear kprobe events
- * @system: System to clear (NULL means default)
- * @event: Name of probe to clear in system (NULL for all probes in system)
- * @force: Will attempt to disable all kprobe events and clear them
- *
- * Will remove the kprobes that match the @system and @event. If @system
- * is NULL, then "kprobes" is used and will ignore all other system
- * groups of kprobes. The @event is NULL then all events under the given
- * @system are removed, otherwise only the event that matches.
- *
- * Returns zero on success, -1 otherwise.
- */
-int tracefs_kprobe_clear_probe(const char *system, const char *event, bool force)
-{
- char **instance_list;
- int ret;
-
- if (!system)
- system = "kprobes";
-
- if (!event)
- return kprobe_clear_probes(system, force);
-
- /*
- * Since we know we are disabling a specific event, try
- * to disable it first before clearing it.
- */
- if (force) {
- instance_list = tracefs_instances(NULL);
- disable_events(system, event, instance_list);
- tracefs_list_free(instance_list);
- }
-
- ret = clear_kprobe(system, event);
-
- return ret < 0 ? -1 : 0;
-}
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 04/12] libtracefs: Reimplement kprobe raw APIs
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (2 preceding siblings ...)
2021-11-08 8:03 ` [PATCH v6 03/12] libtracefs: Remove redundant kprobes APIs Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:03 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:03 ` [PATCH v6 05/12] libtracefs: Extend kprobes unit test Tzvetomir Stoyanov (VMware)
` (7 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:03 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
In order to unify the code and use the new dynamic event helpers, these
kprobe APIs are rewritten:
kracefs_kprobe_raw()
kracefs_kretprobe_raw()
The definition and logic of the APIs remain the same.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
src/tracefs-kprobes.c | 37 ++++++++++---------------------------
1 file changed, 10 insertions(+), 27 deletions(-)
diff --git a/src/tracefs-kprobes.c b/src/tracefs-kprobes.c
index 3f46b8d..a8c0163 100644
--- a/src/tracefs-kprobes.c
+++ b/src/tracefs-kprobes.c
@@ -129,37 +129,20 @@ error:
return NULL;
}
-static int insert_kprobe(const char *type, const char *system,
- const char *event, const char *addr,
- const char *format)
+static int kprobe_raw(enum tracefs_dynevent_type type, const char *system,
+ const char *event, const char *addr, const char *format)
{
- char *str;
+ static struct tracefs_dynevent *kp;
int ret;
- if (!tracefs_file_exists(NULL, KPROBE_EVENTS))
- return -1;
-
- errno = EBADMSG;
- if (!addr || !format)
- return -1;
-
- if (!event)
- event = addr;
-
- if (system)
- ret = asprintf(&str, "%s:%s/%s %s %s\n",
- type, system, event, addr, format);
- else
- ret = asprintf(&str, "%s:%s %s %s\n",
- type, event, addr, format);
-
- if (ret < 0)
+ kp = kprobe_alloc(type, system, event, addr, format);
+ if (!kp)
return -1;
- ret = tracefs_instance_file_append(NULL, KPROBE_EVENTS, str);
- free(str);
+ ret = tracefs_dynevent_create(kp);
+ tracefs_dynevent_free(kp);
- return ret < 0 ? ret : 0;
+ return ret;
}
/**
@@ -185,7 +168,7 @@ static int insert_kprobe(const char *type, const char *system,
int tracefs_kprobe_raw(const char *system, const char *event,
const char *addr, const char *format)
{
- return insert_kprobe("p", system, event, addr, format);
+ return kprobe_raw(TRACEFS_DYNEVENT_KPROBE, system, event, addr, format);
}
/**
@@ -211,5 +194,5 @@ int tracefs_kprobe_raw(const char *system, const char *event,
int tracefs_kretprobe_raw(const char *system, const char *event,
const char *addr, const char *format)
{
- return insert_kprobe("r", system, event, addr, format);
+ return kprobe_raw(TRACEFS_DYNEVENT_KRETPROBE, system, event, addr, format);
}
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 05/12] libtracefs: Extend kprobes unit test
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (3 preceding siblings ...)
2021-11-08 8:03 ` [PATCH v6 04/12] libtracefs: Reimplement kprobe raw APIs Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:03 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:03 ` [PATCH v6 06/12] libtracefs: Rename tracefs_synth_init API Tzvetomir Stoyanov (VMware)
` (6 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:03 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
As there are a lot of changes in the libtracefs kprobes APIs, the unit
test of that functionality should be updated. A new test section is
added, for testing the all kprobes APIs.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
utest/tracefs-utest.c | 423 +++++++++++++++++++++++++-----------------
1 file changed, 253 insertions(+), 170 deletions(-)
diff --git a/utest/tracefs-utest.c b/utest/tracefs-utest.c
index 09bb8f2..5b656d4 100644
--- a/utest/tracefs-utest.c
+++ b/utest/tracefs-utest.c
@@ -28,22 +28,6 @@
#define TRACE_ON "tracing_on"
#define TRACE_CLOCK "trace_clock"
-#define KPROBE_EVENTS "kprobe_events"
-
-#define KPROBE_1_NAME "mkdir"
-#define KPROBE_1_GROUP "kprobes"
-#define KPROBE_1_ADDR "do_mkdirat"
-#define KPROBE_1_FMT "path=+u0($arg2):ustring"
-
-#define KPROBE_2_NAME "open"
-#define KPROBE_2_GROUP "myprobe"
-#define KPROBE_2_ADDR "do_sys_openat2"
-#define KPROBE_2_FMT "file=+u0($arg2):ustring flags=+0($arg3):x64"
-
-#define KRETPROBE_NAME "retopen"
-#define KRETPROBE_ADDR "do_sys_openat2"
-#define KRETPROBE_FMT "ret=$retval"
-
#define SQL_1_EVENT "wakeup_1"
#define SQL_1_SQL "select sched_switch.next_pid as woke_pid, sched_waking.common_pid as waking_pid from sched_waking join sched_switch on sched_switch.next_pid = sched_waking.pid"
@@ -398,6 +382,27 @@ static void test_trace_sql(void)
test_instance_trace_sql(test_instance);
}
+static struct tracefs_dynevent **get_dynevents_check(enum tracefs_dynevent_type types, int count)
+{
+ struct tracefs_dynevent **devents;
+ int i;
+
+ devents = tracefs_dynevent_get_all(types, NULL);
+ if (count) {
+ CU_TEST(devents != NULL);
+ if (!devents)
+ return NULL;
+ i = 0;
+ while (devents[i])
+ i++;
+ CU_TEST(i == count);
+ } else {
+ CU_TEST(devents == NULL);
+ }
+
+ return devents;
+}
+
static void test_trace_file(void)
{
const char *tmp = get_rand_str();
@@ -457,28 +462,252 @@ static void test_instance_file_read(struct tracefs_instance *inst, const char *f
free(file);
}
+#define KPROBE_DEFAULT_GROUP "kprobes"
+struct kprobe_test {
+ enum tracefs_dynevent_type type;
+ char *prefix;
+ char *system;
+ char *event;
+ char *address;
+ char *format;
+};
+
+static bool check_kprobes(struct kprobe_test *kprobes, int count,
+ struct tracefs_dynevent **devents, bool in_system,
+ struct tracefs_instance *instance)
+{
+
+ enum tracefs_dynevent_type ktype;
+ char *ename;
+ char *kaddress;
+ char *kevent;
+ char *ksystem;
+ char *kformat;
+ char *kprefix;
+ int found = 0;
+ int ret;
+ int i, j;
+
+ for (i = 0; devents && devents[i]; i++) {
+ ktype = tracefs_dynevent_info(devents[i], &ksystem,
+ &kevent, &kprefix, &kaddress, &kformat);
+ for (j = 0; j < count; j++) {
+ if (ktype != kprobes[j].type)
+ continue;
+ if (kprobes[j].event)
+ ename = kprobes[j].event;
+ else
+ ename = kprobes[j].address;
+ if (strcmp(ename, kevent))
+ continue;
+ if (kprobes[j].system) {
+ CU_TEST(strcmp(kprobes[j].system, ksystem) == 0);
+ } else {
+ CU_TEST(strcmp(KPROBE_DEFAULT_GROUP, ksystem) == 0);
+ }
+ CU_TEST(strcmp(kprobes[j].address, kaddress) == 0);
+ if (kprobes[j].format) {
+ CU_TEST(strcmp(kprobes[j].format, kformat) == 0);
+ }
+ if (kprobes[j].prefix) {
+ CU_TEST(strcmp(kprobes[j].prefix, kprefix) == 0);
+ }
+ ret = tracefs_event_enable(instance, ksystem, kevent);
+ if (in_system) {
+ CU_TEST(ret == 0);
+ } else {
+ CU_TEST(ret != 0);
+ }
+ ret = tracefs_event_disable(instance, ksystem, kevent);
+ if (in_system) {
+ CU_TEST(ret == 0);
+ } else {
+ CU_TEST(ret != 0);
+ }
+
+ found++;
+ break;
+ }
+ free(ksystem);
+ free(kevent);
+ free(kprefix);
+ free(kaddress);
+ free(kformat);
+ }
+
+ CU_TEST(found == count);
+ if (found != count)
+ return false;
+
+ return true;
+}
+
+static void test_kprobes_instance(struct tracefs_instance *instance)
+{
+ struct kprobe_test ktests[] = {
+ { TRACEFS_DYNEVENT_KPROBE, "p", NULL, "mkdir", "do_mkdirat", "path=+u0($arg2):ustring" },
+ { TRACEFS_DYNEVENT_KPROBE, "p", NULL, "close", "close_fd", NULL },
+ { TRACEFS_DYNEVENT_KPROBE, "p", "ptest", "open2", "do_sys_openat2",
+ "file=+u0($arg2):ustring flags=+0($arg3):x64" },
+ };
+ struct kprobe_test kretests[] = {
+ { TRACEFS_DYNEVENT_KRETPROBE, NULL, NULL, "retopen", "do_sys_openat2", "ret=$retval" },
+ { TRACEFS_DYNEVENT_KRETPROBE, NULL, NULL, NULL, "do_sys_open", "ret=$retval" },
+ };
+ int kretprobe_count = sizeof(kretests) / sizeof((kretests)[0]);
+ int kprobe_count = sizeof(ktests) / sizeof((ktests)[0]);
+ struct tracefs_dynevent **dkretprobe;
+ struct tracefs_dynevent **dkprobe;
+ struct tracefs_dynevent **devents;
+ char *tmp;
+ int ret;
+ int i;
+
+ dkprobe = calloc(kprobe_count + 1, sizeof(*dkprobe));
+ dkretprobe = calloc(kretprobe_count + 1, sizeof(*dkretprobe));
+
+ /* Invalid parameters */
+ CU_TEST(tracefs_kprobe_alloc("test", NULL, NULL, "test") == NULL);
+ CU_TEST(tracefs_kretprobe_alloc("test", NULL, NULL, "test", 0) == NULL);
+ CU_TEST(tracefs_dynevent_create(NULL) != 0);
+ CU_TEST(tracefs_dynevent_info(NULL, &tmp, &tmp, &tmp, &tmp, &tmp) == TRACEFS_DYNEVENT_UNKNOWN);
+ CU_TEST(tracefs_kprobe_raw("test", "test", NULL, "test") != 0);
+ CU_TEST(tracefs_kretprobe_raw("test", "test", NULL, "test") != 0);
+
+ /* kprobes APIs */
+ ret = tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
+ CU_TEST(ret == 0);
+ get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, 0);
+
+ for (i = 0; i < kprobe_count; i++) {
+ dkprobe[i] = tracefs_kprobe_alloc(ktests[i].system, ktests[i].event,
+ ktests[i].address, ktests[i].format);
+ CU_TEST(dkprobe[i] != NULL);
+ }
+ dkprobe[i] = NULL;
+ get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, 0);
+ CU_TEST(check_kprobes(ktests, kprobe_count, dkprobe, false, instance));
+
+ for (i = 0; i < kretprobe_count; i++) {
+ dkretprobe[i] = tracefs_kretprobe_alloc(kretests[i].system, kretests[i].event,
+ kretests[i].address, kretests[i].format, 0);
+ CU_TEST(dkretprobe[i] != NULL);
+ }
+ dkretprobe[i] = NULL;
+ get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, 0);
+ CU_TEST(check_kprobes(kretests, kretprobe_count, dkretprobe, false, instance));
+
+ for (i = 0; i < kprobe_count; i++) {
+ CU_TEST(tracefs_dynevent_create(dkprobe[i]) == 0);
+ }
+ devents = get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE,
+ kprobe_count);
+ CU_TEST(check_kprobes(ktests, kprobe_count, devents, true, instance));
+ CU_TEST(check_kprobes(kretests, kretprobe_count, dkretprobe, false, instance));
+ tracefs_dynevent_list_free(devents);
+ devents = NULL;
+
+ for (i = 0; i < kretprobe_count; i++) {
+ CU_TEST(tracefs_dynevent_create(dkretprobe[i]) == 0);
+ }
+ devents = get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE,
+ kprobe_count + kretprobe_count);
+ CU_TEST(check_kprobes(ktests, kprobe_count, devents, true, instance));
+ CU_TEST(check_kprobes(kretests, kretprobe_count, devents, true, instance));
+ tracefs_dynevent_list_free(devents);
+ devents = NULL;
+
+ for (i = 0; i < kretprobe_count; i++) {
+ CU_TEST(tracefs_dynevent_destroy(dkretprobe[i], false) == 0);
+ }
+ devents = get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE,
+ kprobe_count);
+ CU_TEST(check_kprobes(ktests, kprobe_count, devents, true, instance));
+ CU_TEST(check_kprobes(kretests, kretprobe_count, dkretprobe, false, instance));
+ tracefs_dynevent_list_free(devents);
+ devents = NULL;
+
+ for (i = 0; i < kprobe_count; i++) {
+ CU_TEST(tracefs_dynevent_destroy(dkprobe[i], false) == 0);
+ }
+ get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, 0);
+ CU_TEST(check_kprobes(ktests, kprobe_count, dkprobe, false, instance));
+ CU_TEST(check_kprobes(kretests, kretprobe_count, dkretprobe, false, instance));
+ tracefs_dynevent_list_free(devents);
+ devents = NULL;
+
+ for (i = 0; i < kprobe_count; i++)
+ tracefs_dynevent_free(dkprobe[i]);
+ for (i = 0; i < kretprobe_count; i++)
+ tracefs_dynevent_free(dkretprobe[i]);
+
+ /* kprobes raw APIs */
+ ret = tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
+ CU_TEST(ret == 0);
+ get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, 0);
+
+ for (i = 0; i < kprobe_count; i++) {
+ ret = tracefs_kprobe_raw(ktests[i].system, ktests[i].event,
+ ktests[i].address, ktests[i].format);
+ CU_TEST(ret == 0);
+ }
+
+ devents = get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, kprobe_count);
+ CU_TEST(check_kprobes(ktests, kprobe_count, devents, true, instance));
+ tracefs_dynevent_list_free(devents);
+ devents = NULL;
+
+ for (i = 0; i < kretprobe_count; i++) {
+ ret = tracefs_kretprobe_raw(kretests[i].system, kretests[i].event,
+ kretests[i].address, kretests[i].format);
+ CU_TEST(ret == 0);
+ }
+
+ devents = get_dynevents_check(TRACEFS_DYNEVENT_KPROBE, kprobe_count);
+ CU_TEST(check_kprobes(ktests, kprobe_count, devents, true, instance));
+ tracefs_dynevent_list_free(devents);
+ devents = NULL;
+
+ devents = get_dynevents_check(TRACEFS_DYNEVENT_KRETPROBE, kretprobe_count);
+ CU_TEST(check_kprobes(kretests, kretprobe_count, devents, true, instance));
+ tracefs_dynevent_list_free(devents);
+ devents = NULL;
+
+ devents = get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE,
+ kprobe_count + kretprobe_count);
+ CU_TEST(check_kprobes(ktests, kprobe_count, devents, true, instance));
+ CU_TEST(check_kprobes(kretests, kretprobe_count, devents, true, instance));
+ tracefs_dynevent_list_free(devents);
+ devents = NULL;
+
+ ret = tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
+ CU_TEST(ret == 0);
+ get_dynevents_check(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, 0);
+ free(dkretprobe);
+ free(dkprobe);
+}
+
+static void test_kprobes(void)
+{
+ test_kprobes_instance(test_instance);
+}
+
static void test_instance_file(void)
{
struct tracefs_instance *instance = NULL;
struct tracefs_instance *second = NULL;
- enum tracefs_kprobe_type type;
const char *name = get_rand_str();
const char *inst_name = NULL;
const char *tdir;
char *inst_file;
char *inst_dir;
struct stat st;
- char **kprobes;
- char *kformat;
- char *ktype;
- char *kaddr;
- char *fname;
char *file1;
char *file2;
char *tracer;
+ char *fname;
int size;
int ret;
- int i;
tdir = tracefs_tracing_dir();
CU_TEST(tdir != NULL);
@@ -541,153 +770,6 @@ static void test_instance_file(void)
free(file1);
free(file2);
- ret = tracefs_kprobe_clear_all(true);
- CU_TEST(ret == 0);
- ret = tracefs_kprobe_raw(NULL, KPROBE_1_NAME, KPROBE_1_ADDR, KPROBE_1_FMT);
- CU_TEST(ret == 0);
- ret = tracefs_kprobe_raw(KPROBE_2_GROUP, KPROBE_2_NAME, KPROBE_2_ADDR,
- KPROBE_2_FMT);
- CU_TEST(ret == 0);
-
- ret = tracefs_kretprobe_raw(KPROBE_2_GROUP, KRETPROBE_NAME, KRETPROBE_ADDR,
- KRETPROBE_FMT);
- CU_TEST(ret == 0);
-
- type = tracefs_kprobe_info(KPROBE_1_GROUP, KPROBE_1_NAME, &ktype,
- &kaddr, &kformat);
- CU_TEST(type == TRACEFS_KPROBE);
- CU_TEST(ktype && *ktype == 'p');
- CU_TEST(kaddr && !strcmp(kaddr, KPROBE_1_ADDR));
- CU_TEST(kformat && !strcmp(kformat, KPROBE_1_FMT));
- free(ktype);
- free(kaddr);
- free(kformat);
-
- type = tracefs_kprobe_info(KPROBE_2_GROUP, KPROBE_2_NAME, &ktype,
- &kaddr, &kformat);
- CU_TEST(type == TRACEFS_KPROBE);
- CU_TEST(ktype && *ktype == 'p');
- CU_TEST(kaddr && !strcmp(kaddr, KPROBE_2_ADDR));
- CU_TEST(kformat && !strcmp(kformat, KPROBE_2_FMT));
- free(ktype);
- free(kaddr);
- free(kformat);
-
- type = tracefs_kprobe_info(KPROBE_2_GROUP, KRETPROBE_NAME, &ktype,
- &kaddr, &kformat);
- CU_TEST(type == TRACEFS_KRETPROBE);
- CU_TEST(ktype && *ktype == 'r');
- CU_TEST(kaddr && !strcmp(kaddr, KRETPROBE_ADDR));
- CU_TEST(kformat && !strcmp(kformat, KRETPROBE_FMT));
- free(ktype);
- free(kaddr);
- free(kformat);
-
- kprobes = tracefs_get_kprobes(TRACEFS_ALL_KPROBES);
- CU_TEST(kprobes != NULL);
-
- for (i = 0; kprobes[i]; i++) {
- char *system = strtok(kprobes[i], "/");
- char *event = strtok(NULL, "");
- bool found = false;
- if (!strcmp(system, KPROBE_1_GROUP)) {
- CU_TEST(!strcmp(event, KPROBE_1_NAME));
- found = true;
- } else if (!strcmp(system, KPROBE_2_GROUP)) {
- switch (tracefs_kprobe_info(system, event, NULL, NULL, NULL)) {
- case TRACEFS_KPROBE:
- CU_TEST(!strcmp(event, KPROBE_2_NAME));
- found = true;
- break;
- case TRACEFS_KRETPROBE:
- CU_TEST(!strcmp(event, KRETPROBE_NAME));
- found = true;
- break;
- default:
- break;
- }
- }
- CU_TEST(found);
- }
- tracefs_list_free(kprobes);
- CU_TEST(i == 3);
-
- kprobes = tracefs_get_kprobes(TRACEFS_KPROBE);
- CU_TEST(kprobes != NULL);
-
- for (i = 0; kprobes[i]; i++) {
- char *system = strtok(kprobes[i], "/");
- char *event = strtok(NULL, "");
- bool found = false;
- if (!strcmp(system, KPROBE_1_GROUP)) {
- CU_TEST(!strcmp(event, KPROBE_1_NAME));
- found = true;
- } else if (!strcmp(system, KPROBE_2_GROUP)) {
- CU_TEST(!strcmp(event, KPROBE_2_NAME));
- found = true;
- }
- CU_TEST(found);
- }
- tracefs_list_free(kprobes);
- CU_TEST(i == 2);
-
- kprobes = tracefs_get_kprobes(TRACEFS_KRETPROBE);
- CU_TEST(kprobes != NULL);
-
- for (i = 0; kprobes[i]; i++) {
- char *system = strtok(kprobes[i], "/");
- char *event = strtok(NULL, "");
- bool found = false;
- if (!strcmp(system, KPROBE_2_GROUP)) {
- CU_TEST(!strcmp(event, KRETPROBE_NAME));
- found = true;
- }
- CU_TEST(found);
- }
- tracefs_list_free(kprobes);
- CU_TEST(i == 1);
-
- ret = tracefs_event_enable(instance, KPROBE_1_GROUP, KPROBE_1_NAME);
- CU_TEST(ret == 0);
- ret = tracefs_event_enable(instance, KPROBE_2_GROUP, KPROBE_2_NAME);
- CU_TEST(ret == 0);
- ret = tracefs_event_enable(instance, KPROBE_2_GROUP, KRETPROBE_NAME);
- CU_TEST(ret == 0);
-
- ret = tracefs_kprobe_clear_all(false);
- CU_TEST(ret < 0);
-
- ret = tracefs_kprobe_clear_probe(KPROBE_2_GROUP, NULL, false);
- CU_TEST(ret < 0);
-
- ret = tracefs_kprobe_clear_probe(KPROBE_2_GROUP, NULL, true);
- CU_TEST(ret == 0);
-
- kprobes = tracefs_get_kprobes(TRACEFS_ALL_KPROBES);
- CU_TEST(kprobes != NULL);
-
- for (i = 0; kprobes[i]; i++) {
- char *system = strtok(kprobes[i], "/");
- char *event = strtok(NULL, "");
- bool found = false;
- if (!strcmp(system, KPROBE_1_GROUP)) {
- CU_TEST(!strcmp(event, KPROBE_1_NAME));
- found = true;
- }
- CU_TEST(found);
- }
- tracefs_list_free(kprobes);
- CU_TEST(i == 1);
-
- ret = tracefs_kprobe_clear_all(true);
- CU_TEST(ret == 0);
-
- kprobes = tracefs_get_kprobes(TRACEFS_ALL_KPROBES);
- CU_TEST(kprobes != NULL);
-
- CU_TEST(kprobes[0] == NULL);
- tracefs_list_free(kprobes);
-
tracefs_put_tracing_file(inst_file);
free(fname);
@@ -1442,4 +1524,5 @@ void test_tracefs_lib(void)
test_custom_trace_dir);
CU_add_test(suite, "ftrace marker",
test_ftrace_marker);
+ CU_add_test(suite, "kprobes", test_kprobes);
}
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 06/12] libtracefs: Rename tracefs_synth_init API
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (4 preceding siblings ...)
2021-11-08 8:03 ` [PATCH v6 05/12] libtracefs: Extend kprobes unit test Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:03 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:03 ` [PATCH v6 07/12] libtracefs: Use the internal dynamic events API when creating synthetic events Tzvetomir Stoyanov (VMware)
` (5 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:03 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
In order to be consistent with the others library APIs, the
tracefs_synth_init() is renamed to tracefs_synth_alloc().
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
Documentation/libtracefs-synth.txt | 20 ++++++++++----------
Documentation/libtracefs-synth2.txt | 10 +++++-----
include/tracefs.h | 18 +++++++++---------
src/tracefs-hist.c | 22 +++++++++++-----------
src/tracefs-sqlhist.c | 6 +++---
5 files changed, 38 insertions(+), 38 deletions(-)
diff --git a/Documentation/libtracefs-synth.txt b/Documentation/libtracefs-synth.txt
index 77076e1..2fd9019 100644
--- a/Documentation/libtracefs-synth.txt
+++ b/Documentation/libtracefs-synth.txt
@@ -3,7 +3,7 @@ libtracefs(3)
NAME
----
-tracefs_synth_init, tracefs_synth_add_match_field, tracefs_synth_add_compare_field, tracefs_synth_add_start_field,
+tracefs_synth_alloc, tracefs_synth_add_match_field, tracefs_synth_add_compare_field, tracefs_synth_add_start_field,
tracefs_synth_add_end_field, tracefs_synth_append_start_filter, tracefs_synth_append_end_filter, tracefs_synth_free,
- Creation of a synthetic event descriptor
@@ -13,7 +13,7 @@ SYNOPSIS
--
*#include <tracefs.h>*
-struct tracefs_synth pass:[*]tracefs_synth_init(struct tep_handle pass:[*]tep,
+struct tracefs_synth pass:[*]tracefs_synth_alloc(struct tep_handle pass:[*]tep,
const char pass:[*]name,
const char pass:[*]start_system,
const char pass:[*]start_event,
@@ -69,7 +69,7 @@ as a field for both events to calculate the delta in nanoseconds, or use
*TRACEFS_TIMESTAMP_USECS" as the compare fields for both events to calculate the
delta in microseconds. This is used as the example below.
-*tracefs_synth_init*() allocates and initializes a synthetic event.
+*tracefs_synth_alloc*() allocates and initializes a synthetic event.
It does not create the synthetic event, but supplies the minimal information
to do so. See *tracefs_synth_create*(3) for how to create the synthetic
event in the system. It requires a _tep_ handler that can be created by
@@ -156,11 +156,11 @@ _field_, _compare_, and _val_ are ignored unless _type_ is equal to
filters on the ending event.
*tracefs_synth_free*() frees the allocated descriptor returned by
-*tracefs_synth_init*().
+*tracefs_synth_alloc*().
RETURN VALUE
------------
-*tracefs_synth_init*() returns an allocated struct tracefs_synth descriptor
+*tracefs_synth_alloc*() returns an allocated struct tracefs_synth descriptor
on sucess or NULL on error.
All other functions that return an integer returns zero on success or -1
@@ -209,11 +209,11 @@ static void make_event(void)
tep = tracefs_local_events(NULL);
/* Initialize the synthetic event */
- synth = tracefs_synth_init(tep, "wakeup_lat",
- NULL, start_event,
- NULL, end_event,
- start_field, end_field,
- match_name);
+ synth = tracefs_synth_alloc(tep, "wakeup_lat",
+ NULL, start_event,
+ NULL, end_event,
+ start_field, end_field,
+ match_name);
/* The tep is no longer needed */
tep_free(tep);
diff --git a/Documentation/libtracefs-synth2.txt b/Documentation/libtracefs-synth2.txt
index 4c44253..f734b44 100644
--- a/Documentation/libtracefs-synth2.txt
+++ b/Documentation/libtracefs-synth2.txt
@@ -142,11 +142,11 @@ static void make_event(void)
tep = tracefs_local_events(NULL);
/* Initialize the synthetic event */
- synth = tracefs_synth_init(tep, "wakeup_lat",
- NULL, start_event,
- NULL, end_event,
- start_field, end_field,
- match_name);
+ synth = tracefs_synth_alloc(tep, "wakeup_lat",
+ NULL, start_event,
+ NULL, end_event,
+ start_field, end_field,
+ match_name);
/* The tep is no longer needed */
tep_free(tep);
diff --git a/include/tracefs.h b/include/tracefs.h
index 25d9e9a..1092609 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -479,15 +479,15 @@ enum tracefs_synth_handler {
TRACEFS_SYNTH_HANDLE_CHANGE,
};
-struct tracefs_synth *tracefs_synth_init(struct tep_handle *tep,
- const char *name,
- const char *start_system,
- const char *start_event,
- const char *end_system,
- const char *end_event,
- const char *start_match_field,
- const char *end_match_field,
- const char *match_name);
+struct tracefs_synth *tracefs_synth_alloc(struct tep_handle *tep,
+ const char *name,
+ const char *start_system,
+ const char *start_event,
+ const char *end_system,
+ const char *end_event,
+ const char *start_match_field,
+ const char *end_match_field,
+ const char *match_name);
int tracefs_synth_add_match_field(struct tracefs_synth *synth,
const char *start_match_field,
const char *end_match_field,
diff --git a/src/tracefs-hist.c b/src/tracefs-hist.c
index 27bab00..9009dba 100644
--- a/src/tracefs-hist.c
+++ b/src/tracefs-hist.c
@@ -692,7 +692,7 @@ static void action_free(struct action *action)
* @synth: The tracefs_synth descriptor
*
* Frees the resources allocated for a @synth created with
- * tracefs_synth_init(). It does not touch the system. That is,
+ * tracefs_synth_alloc(). It does not touch the system. That is,
* any synthetic event created, will not be destroyed by this
* function.
*/
@@ -890,7 +890,7 @@ synth_init_from(struct tep_handle *tep, const char *start_system,
}
/**
- * tracefs_synth_init - create a new tracefs_synth instance
+ * tracefs_synth_alloc - create a new tracefs_synth instance
* @tep: The tep handle that holds the events to work on
* @name: The name of the synthetic event being created
* @start_system: The name of the system of the start event (can be NULL)
@@ -933,15 +933,15 @@ synth_init_from(struct tep_handle *tep, const char *start_system,
* event on the system is not created. That needs to be done with
* tracefs_synth_create().
*/
-struct tracefs_synth *tracefs_synth_init(struct tep_handle *tep,
- const char *name,
- const char *start_system,
- const char *start_event_name,
- const char *end_system,
- const char *end_event_name,
- const char *start_match_field,
- const char *end_match_field,
- const char *match_name)
+struct tracefs_synth *tracefs_synth_alloc(struct tep_handle *tep,
+ const char *name,
+ const char *start_system,
+ const char *start_event_name,
+ const char *end_system,
+ const char *end_event_name,
+ const char *start_match_field,
+ const char *end_match_field,
+ const char *match_name)
{
struct tep_event *end_event;
struct tracefs_synth *synth;
diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index d77ce86..016f3eb 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -1419,9 +1419,9 @@ static struct tracefs_synth *build_synth(struct tep_handle *tep,
assign_match(start_system, start_event, match,
&start_match, &end_match);
- synth = tracefs_synth_init(tep, name, start_system,
- start_event, end_system, end_event,
- start_match, end_match, NULL);
+ synth = tracefs_synth_alloc(tep, name, start_system,
+ start_event, end_system, end_event,
+ start_match, end_match, NULL);
if (!synth)
return synth_init_error(tep, table);
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 07/12] libtracefs: Use the internal dynamic events API when creating synthetic events
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (5 preceding siblings ...)
2021-11-08 8:03 ` [PATCH v6 06/12] libtracefs: Rename tracefs_synth_init API Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:03 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:04 ` [PATCH v6 08/12] libtracefs: Remove instance parameter from synthetic events APIs Tzvetomir Stoyanov (VMware)
` (4 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:03 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
Synthetic events are type of ftrace dynamic events. The tracefs library
has dedicated APIs to manage dynamic events of all types. In order the
code to be consistent, the creation of synthetic events inside the
library is reimplemented with these new dynamic events APIs.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
src/tracefs-hist.c | 105 +++++++++++++++++++++------------------------
1 file changed, 49 insertions(+), 56 deletions(-)
diff --git a/src/tracefs-hist.c b/src/tracefs-hist.c
index 9009dba..2685dab 100644
--- a/src/tracefs-hist.c
+++ b/src/tracefs-hist.c
@@ -24,6 +24,8 @@
#define ASCENDING ".ascending"
#define DESCENDING ".descending"
+#define SYNTHETIC_GROUP "synthetic"
+
struct tracefs_hist {
struct tep_handle *tep;
struct tep_event *event;
@@ -661,6 +663,7 @@ struct tracefs_synth {
struct tep_event *end_event;
struct action *actions;
struct action **next_action;
+ struct tracefs_dynevent *dyn_event;
char *name;
char **synthetic_fields;
char **synthetic_args;
@@ -719,6 +722,7 @@ void tracefs_synth_free(struct tracefs_synth *synth)
synth->actions = action->next;
action_free(action);
}
+ tracefs_dynevent_free(synth->dyn_event);
free(synth);
}
@@ -889,6 +893,28 @@ synth_init_from(struct tep_handle *tep, const char *start_system,
return synth;
}
+static int alloc_synthetic_event(struct tracefs_synth *synth)
+{
+ char *format;
+ const char *field;
+ int i;
+
+ format = strdup("");
+ if (!format)
+ return -1;
+
+ for (i = 0; synth->synthetic_fields && synth->synthetic_fields[i]; i++) {
+ field = synth->synthetic_fields[i];
+ format = append_string(format, i ? " " : NULL, field);
+ }
+
+ synth->dyn_event = dynevent_alloc(TRACEFS_DYNEVENT_SYNTH, SYNTHETIC_GROUP,
+ synth->name, NULL, format);
+ free(format);
+
+ return synth->dyn_event ? 0 : -1;
+}
+
/**
* tracefs_synth_alloc - create a new tracefs_synth instance
* @tep: The tep handle that holds the events to work on
@@ -1609,38 +1635,6 @@ int tracefs_synth_save(struct tracefs_synth *synth,
return 0;
}
-static char *create_synthetic_event(struct tracefs_synth *synth)
-{
- char *synthetic_event;
- const char *field;
- int i;
-
- synthetic_event = strdup(synth->name);
- if (!synthetic_event)
- return NULL;
-
- for (i = 0; synth->synthetic_fields && synth->synthetic_fields[i]; i++) {
- field = synth->synthetic_fields[i];
- synthetic_event = append_string(synthetic_event, " ", field);
- }
-
- return synthetic_event;
-}
-
-static int remove_synthetic(const char *synthetic)
-{
- char *str;
- int ret;
-
- ret = asprintf(&str, "!%s", synthetic);
- if (ret < 0)
- return -1;
-
- ret = tracefs_instance_file_append(NULL, "synthetic_events", str);
- free(str);
- return ret < 0 ? -1 : 0;
-}
-
static int remove_hist(struct tracefs_instance *instance,
struct tep_event *event, const char *hist)
{
@@ -1919,7 +1913,6 @@ tracefs_synth_get_start_hist(struct tracefs_synth *synth)
int tracefs_synth_create(struct tracefs_instance *instance,
struct tracefs_synth *synth)
{
- char *synthetic_event;
char *start_hist = NULL;
char *end_hist = NULL;
int ret;
@@ -1937,14 +1930,10 @@ int tracefs_synth_create(struct tracefs_instance *instance,
if (verify_state(synth) < 0)
return -1;
- synthetic_event = create_synthetic_event(synth);
- if (!synthetic_event)
+ if (!synth->dyn_event && alloc_synthetic_event(synth))
+ return -1;
+ if (tracefs_dynevent_create(synth->dyn_event))
return -1;
-
- ret = tracefs_instance_file_append(NULL, "synthetic_events",
- synthetic_event);
- if (ret < 0)
- goto free_synthetic;
start_hist = create_hist(synth->start_keys, synth->start_vars);
start_hist = append_filter(start_hist, synth->start_filter,
@@ -1980,9 +1969,7 @@ int tracefs_synth_create(struct tracefs_instance *instance,
remove_synthetic:
free(end_hist);
free(start_hist);
- remove_synthetic(synthetic_event);
- free_synthetic:
- free(synthetic_event);
+ tracefs_dynevent_destroy(synth->dyn_event, false);
return -1;
}
@@ -2007,7 +1994,6 @@ int tracefs_synth_create(struct tracefs_instance *instance,
int tracefs_synth_destroy(struct tracefs_instance *instance,
struct tracefs_synth *synth)
{
- char *synthetic_event;
char *hist;
int ret;
@@ -2041,11 +2027,7 @@ int tracefs_synth_destroy(struct tracefs_instance *instance,
ret = remove_hist(instance, synth->start_event, hist);
free(hist);
- synthetic_event = create_synthetic_event(synth);
- if (!synthetic_event)
- return -1;
-
- ret = remove_synthetic(synthetic_event);
+ ret = tracefs_dynevent_destroy(synth->dyn_event, true);
return ret ? -1 : 0;
}
@@ -2067,7 +2049,7 @@ int tracefs_synth_show(struct trace_seq *seq,
struct tracefs_instance *instance,
struct tracefs_synth *synth)
{
- char *synthetic_event = NULL;
+ bool new_event = false;
char *hist = NULL;
char *path;
int ret = -1;
@@ -2082,16 +2064,19 @@ int tracefs_synth_show(struct trace_seq *seq,
return -1;
}
- synthetic_event = create_synthetic_event(synth);
- if (!synthetic_event)
- return -1;
+ if (!synth->dyn_event) {
+ if (alloc_synthetic_event(synth))
+ return -1;
+ new_event = true;
+ }
path = trace_find_tracing_dir();
if (!path)
goto out_free;
- trace_seq_printf(seq, "echo '%s' > %s/synthetic_events\n",
- synthetic_event, path);
+ trace_seq_printf(seq, "echo '%s%s %s' > %s/%s\n",
+ synth->dyn_event->prefix, synth->dyn_event->event,
+ synth->dyn_event->format, path, synth->dyn_event->trace_file);
tracefs_put_tracing_file(path);
path = tracefs_instance_get_dir(instance);
@@ -2116,10 +2101,18 @@ int tracefs_synth_show(struct trace_seq *seq,
hist, path, synth->end_event->system,
synth->end_event->name);
+ if (new_event) {
+ tracefs_dynevent_free(synth->dyn_event);
+ synth->dyn_event = NULL;
+ }
+
ret = 0;
out_free:
- free(synthetic_event);
free(hist);
tracefs_put_tracing_file(path);
+ if (new_event) {
+ tracefs_dynevent_free(synth->dyn_event);
+ synth->dyn_event = NULL;
+ }
return ret;
}
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 08/12] libtracefs: Remove instance parameter from synthetic events APIs
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (6 preceding siblings ...)
2021-11-08 8:03 ` [PATCH v6 07/12] libtracefs: Use the internal dynamic events API when creating synthetic events Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:04 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:04 ` [PATCH v6 09/12] libtracefs: Add unit test for synthetic events Tzvetomir Stoyanov (VMware)
` (3 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:04 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
The synthetic events apply across all instances, but some histograms
configuration is performed in specific instance. That configuration is
implementation detail of the synthetic event and should not be part of
the API. These APIs are affected by the change:
tracefs_synth_create()
tracefs_synth_destroy()
tracefs_synth_show()
Now, the top trace instance is used by default. If there is a use case
for a custom instance, a new API could be proposed in the future:
tracefs_synth_add_instance()
that will associate the synthetic event with a custom instance, before
calling the create API.
Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Suggested-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com>
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
Documentation/libtracefs-sql.txt | 4 ++--
Documentation/libtracefs-synth.txt | 6 ++---
Documentation/libtracefs-synth2.txt | 30 ++++++++++--------------
include/tracefs.h | 9 +++-----
src/tracefs-hist.c | 36 ++++++++++++-----------------
utest/tracefs-utest.c | 10 ++++----
6 files changed, 40 insertions(+), 55 deletions(-)
diff --git a/Documentation/libtracefs-sql.txt b/Documentation/libtracefs-sql.txt
index e762eae..73984ae 100644
--- a/Documentation/libtracefs-sql.txt
+++ b/Documentation/libtracefs-sql.txt
@@ -405,9 +405,9 @@ static int do_sql(const char *buffer, const char *name, const char *var,
}
}
}
- tracefs_synth_show(&seq, NULL, synth);
+ tracefs_synth_show(&seq, synth);
if (execute)
- tracefs_synth_create(NULL, synth);
+ tracefs_synth_create(synth);
} else {
struct tracefs_hist *hist;
hist = tracefs_synth_get_start_hist(synth);
diff --git a/Documentation/libtracefs-synth.txt b/Documentation/libtracefs-synth.txt
index 2fd9019..e238f46 100644
--- a/Documentation/libtracefs-synth.txt
+++ b/Documentation/libtracefs-synth.txt
@@ -268,7 +268,7 @@ static void show_event(void)
trace_seq_init(&s);
- tracefs_synth_show(&s, NULL, synth);
+ tracefs_synth_show(&s, synth);
trace_seq_terminate(&s);
trace_seq_do_printf(&s);
trace_seq_destroy(&s);
@@ -281,10 +281,10 @@ int main (int argc, char **argv)
if (argc > 1) {
if (!strcmp(argv[1], "create")) {
/* Create the synthetic event */
- tracefs_synth_create(NULL, synth);
+ tracefs_synth_create(synth);
} else if (!strcmp(argv[1], "delete")) {
/* Delete the synthetic event */
- tracefs_synth_destroy(NULL, synth);
+ tracefs_synth_destroy(synth);
} else {
printf("usage: %s [create|delete]\n", argv[0]);
exit(-1);
diff --git a/Documentation/libtracefs-synth2.txt b/Documentation/libtracefs-synth2.txt
index f734b44..95f3092 100644
--- a/Documentation/libtracefs-synth2.txt
+++ b/Documentation/libtracefs-synth2.txt
@@ -12,12 +12,9 @@ SYNOPSIS
--
*#include <tracefs.h>*
-int tracefs_synth_create(struct tracefs_instance pass:[*]instance,
- struct tracefs_synth pass:[*]synth);
-int tracefs_synth_destroy(struct tracefs_instance pass:[*]instance,
- struct tracefs_synth pass:[*]synth);
-int tracefs_synth_show(struct trace_seq pass:[*]seq, struct tracefs_instance pass:[*]instance,
- struct tracefs_synth pass:[*]synth);
+int tracefs_synth_create(struct tracefs_synth pass:[*]synth);
+int tracefs_synth_destroy(struct tracefs_synth pass:[*]synth);
+int tracefs_synth_show(struct trace_seq pass:[*]seq, struct tracefs_synth pass:[*]synth);
bool tracefs_synth_complete(struct tracefs_synth pass:[*]synth);
struct tracefs_hist pass:[*]tracefs_synth_get_start_hist(struct tracefs_synth pass:[*]synth);
@@ -49,18 +46,15 @@ as a field for both events to calculate the delta in nanoseconds, or use
*TRACEFS_TIMESTAMP_USECS" as the compare fields for both events to calculate the
delta in microseconds. This is used as the example below.
-*tracefs_synth_create*() creates the synthetic event in the system in the system
-in the _instance_ provided. Note, synthetic events apply across all instances,
-but some creation requires histograms to be established, which are local to
-instances.
+*tracefs_synth_create*() creates the synthetic event in the system. The synthetic events apply
+across all instances.
-*tracefs_synth_destroy*() destroys the synthetic event. It will attempt to stop
-the running of it in the given _instance_, but if its running in another instance
-this may fail as busy.
+*tracefs_synth_destroy*() destroys the synthetic event. It will attempt to stop the running of it in
+its instance (top by default), but if its running in another instance this may fail as busy.
*tracefs_synth_show*() acts like *tracefs_synth_create*(), but instead of creating
-the synthetic event in the given _instance_, it will write the echo commands to
-manually create it in the _seq_ given.
+the synthetic event in the system, it will write the echo commands to manually create
+it in the _seq_ given.
*tracefs_synth_complete*() returns true if the synthetic event _synth_ has both
a starting and ending event.
@@ -201,7 +195,7 @@ static void show_event(void)
trace_seq_init(&s);
- tracefs_synth_show(&s, NULL, synth);
+ tracefs_synth_show(&s, synth);
trace_seq_terminate(&s);
trace_seq_do_printf(&s);
trace_seq_destroy(&s);
@@ -214,10 +208,10 @@ int main (int argc, char **argv)
if (argc > 1) {
if (!strcmp(argv[1], "create")) {
/* Create the synthetic event */
- tracefs_synth_create(NULL, synth);
+ tracefs_synth_create(synth);
} else if (!strcmp(argv[1], "delete")) {
/* Delete the synthetic event */
- tracefs_synth_destroy(NULL, synth);
+ tracefs_synth_destroy(synth);
} else {
printf("usage: %s [create|delete]\n", argv[0]);
exit(-1);
diff --git a/include/tracefs.h b/include/tracefs.h
index 1092609..7b3f92b 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -522,13 +522,10 @@ int tracefs_synth_save(struct tracefs_synth *synth,
char **save_fields);
bool tracefs_synth_complete(struct tracefs_synth *synth);
struct tracefs_hist *tracefs_synth_get_start_hist(struct tracefs_synth *synth);
-int tracefs_synth_create(struct tracefs_instance *instance,
- struct tracefs_synth *synth);
-int tracefs_synth_destroy(struct tracefs_instance *instance,
- struct tracefs_synth *synth);
+int tracefs_synth_create(struct tracefs_synth *synth);
+int tracefs_synth_destroy(struct tracefs_synth *synth);
void tracefs_synth_free(struct tracefs_synth *synth);
-int tracefs_synth_show(struct trace_seq *seq, struct tracefs_instance *instance,
- struct tracefs_synth *synth);
+int tracefs_synth_show(struct trace_seq *seq, struct tracefs_synth *synth);
struct tracefs_synth *tracefs_sql(struct tep_handle *tep, const char *name,
const char *sql_buffer, char **err);
diff --git a/src/tracefs-hist.c b/src/tracefs-hist.c
index 2685dab..005fa8f 100644
--- a/src/tracefs-hist.c
+++ b/src/tracefs-hist.c
@@ -658,6 +658,7 @@ struct action {
* @end_parens: Current parenthesis level for end event
*/
struct tracefs_synth {
+ struct tracefs_instance *instance;
struct tep_handle *tep;
struct tep_event *start_event;
struct tep_event *end_event;
@@ -1898,11 +1899,9 @@ tracefs_synth_get_start_hist(struct tracefs_synth *synth)
/**
* tracefs_synth_create - creates the synthetic event on the system
- * @instance: The instance to modify the start and end events
* @synth: The tracefs_synth descriptor
*
- * This creates the synthetic events. The @instance is used for writing
- * the triggers into the start and end events.
+ * This creates the synthetic events.
*
* Returns 0 on succes and -1 on error.
* On error, errno is set to:
@@ -1910,8 +1909,7 @@ tracefs_synth_get_start_hist(struct tracefs_synth *synth)
* ENIVAL - a parameter is passed as NULL that should not be or a problem
* writing into the system.
*/
-int tracefs_synth_create(struct tracefs_instance *instance,
- struct tracefs_synth *synth)
+int tracefs_synth_create(struct tracefs_synth *synth)
{
char *start_hist = NULL;
char *end_hist = NULL;
@@ -1947,13 +1945,13 @@ int tracefs_synth_create(struct tracefs_instance *instance,
if (!end_hist)
goto remove_synthetic;
- ret = tracefs_event_file_append(instance, synth->start_event->system,
+ ret = tracefs_event_file_append(synth->instance, synth->start_event->system,
synth->start_event->name,
"trigger", start_hist);
if (ret < 0)
goto remove_synthetic;
- ret = tracefs_event_file_append(instance, synth->end_event->system,
+ ret = tracefs_event_file_append(synth->instance, synth->end_event->system,
synth->end_event->name,
"trigger", end_hist);
if (ret < 0)
@@ -1965,7 +1963,7 @@ int tracefs_synth_create(struct tracefs_instance *instance,
return 0;
remove_start_hist:
- remove_hist(instance, synth->start_event, start_hist);
+ remove_hist(synth->instance, synth->start_event, start_hist);
remove_synthetic:
free(end_hist);
free(start_hist);
@@ -1975,15 +1973,14 @@ int tracefs_synth_create(struct tracefs_instance *instance,
/**
* tracefs_synth_destroy - delete the synthetic event from the system
- * @instance: The instance to modify the start and end events
* @synth: The tracefs_synth descriptor
*
* This will destroy a synthetic event created by tracefs_synth_create()
- * with the same @instance and @synth.
+ * with the same @synth.
*
- * It will attempt to disable the synthetic event, but if other instances
- * have it active, it is likely to fail, which will likely fail on
- * all other parts of tearing down the synthetic event.
+ * It will attempt to disable the synthetic event in its instance (top by default),
+ * but if other instances have it active, it is likely to fail, which will likely
+ * fail on all other parts of tearing down the synthetic event.
*
* Returns 0 on succes and -1 on error.
* On error, errno is set to:
@@ -1991,8 +1988,7 @@ int tracefs_synth_create(struct tracefs_instance *instance,
* ENIVAL - a parameter is passed as NULL that should not be or a problem
* writing into the system.
*/
-int tracefs_synth_destroy(struct tracefs_instance *instance,
- struct tracefs_synth *synth)
+int tracefs_synth_destroy(struct tracefs_synth *synth)
{
char *hist;
int ret;
@@ -2008,14 +2004,14 @@ int tracefs_synth_destroy(struct tracefs_instance *instance,
}
/* Try to disable the event if possible */
- tracefs_event_disable(instance, "synthetic", synth->name);
+ tracefs_event_disable(synth->instance, "synthetic", synth->name);
hist = create_end_hist(synth);
hist = append_filter(hist, synth->end_filter,
synth->end_parens);
if (!hist)
return -1;
- ret = remove_hist(instance, synth->end_event, hist);
+ ret = remove_hist(synth->instance, synth->end_event, hist);
free(hist);
hist = create_hist(synth->start_keys, synth->start_vars);
@@ -2024,7 +2020,7 @@ int tracefs_synth_destroy(struct tracefs_instance *instance,
if (!hist)
return -1;
- ret = remove_hist(instance, synth->start_event, hist);
+ ret = remove_hist(synth->instance, synth->start_event, hist);
free(hist);
ret = tracefs_dynevent_destroy(synth->dyn_event, true);
@@ -2035,7 +2031,6 @@ int tracefs_synth_destroy(struct tracefs_instance *instance,
/**
* tracefs_synth_show - show the command lines to create the synthetic event
* @seq: The trace_seq to store the command lines in
- * @instance: The instance to modify the start and end events
* @synth: The tracefs_synth descriptor
*
* This will list the "echo" commands that are equivalent to what would
@@ -2046,7 +2041,6 @@ int tracefs_synth_destroy(struct tracefs_instance *instance,
* ENOMEM - memory allocation failure.
*/
int tracefs_synth_show(struct trace_seq *seq,
- struct tracefs_instance *instance,
struct tracefs_synth *synth)
{
bool new_event = false;
@@ -2079,7 +2073,7 @@ int tracefs_synth_show(struct trace_seq *seq,
synth->dyn_event->format, path, synth->dyn_event->trace_file);
tracefs_put_tracing_file(path);
- path = tracefs_instance_get_dir(instance);
+ path = tracefs_instance_get_dir(synth->instance);
hist = create_hist(synth->start_keys, synth->start_vars);
hist = append_filter(hist, synth->start_filter,
diff --git a/utest/tracefs-utest.c b/utest/tracefs-utest.c
index 5b656d4..75ac147 100644
--- a/utest/tracefs-utest.c
+++ b/utest/tracefs-utest.c
@@ -337,28 +337,28 @@ static void test_instance_trace_sql(struct tracefs_instance *instance)
synth = tracefs_sql(tep, SQL_1_EVENT, SQL_1_SQL, NULL);
CU_TEST(synth != NULL);
- ret = tracefs_synth_show(&seq, instance, synth);
+ ret = tracefs_synth_show(&seq, synth);
CU_TEST(ret == 0);
tracefs_synth_free(synth);
trace_seq_reset(&seq);
synth = tracefs_sql(tep, SQL_2_EVENT, SQL_2_SQL, NULL);
CU_TEST(synth != NULL);
- ret = tracefs_synth_show(&seq, instance, synth);
+ ret = tracefs_synth_show(&seq, synth);
CU_TEST(ret == 0);
tracefs_synth_free(synth);
trace_seq_reset(&seq);
synth = tracefs_sql(tep, SQL_3_EVENT, SQL_3_SQL, NULL);
CU_TEST(synth != NULL);
- ret = tracefs_synth_show(&seq, instance, synth);
+ ret = tracefs_synth_show(&seq, synth);
CU_TEST(ret == 0);
tracefs_synth_free(synth);
trace_seq_reset(&seq);
synth = tracefs_sql(tep, SQL_4_EVENT, SQL_4_SQL, NULL);
CU_TEST(synth != NULL);
- ret = tracefs_synth_show(&seq, instance, synth);
+ ret = tracefs_synth_show(&seq, synth);
CU_TEST(ret == 0);
tracefs_synth_free(synth);
trace_seq_reset(&seq);
@@ -367,7 +367,7 @@ static void test_instance_trace_sql(struct tracefs_instance *instance)
if (event) {
synth = tracefs_sql(tep, SQL_5_EVENT, SQL_5_SQL, NULL);
CU_TEST(synth != NULL);
- ret = tracefs_synth_show(&seq, instance, synth);
+ ret = tracefs_synth_show(&seq, synth);
CU_TEST(ret == 0);
tracefs_synth_free(synth);
trace_seq_reset(&seq);
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 09/12] libtracefs: Add unit test for synthetic events
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (7 preceding siblings ...)
2021-11-08 8:04 ` [PATCH v6 08/12] libtracefs: Remove instance parameter from synthetic events APIs Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:04 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:04 ` [PATCH v6 10/12] libtracefs: Update kprobes man pages Tzvetomir Stoyanov (VMware)
` (2 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:04 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
All tracefs library APIs should be covered in the unit test. There is
unit test section for the tracefs_sql* set of APIs, which use synthetic
events internally, but no tests for the tracefs_synthetic* APIs.
An initial unit test section is added for tracefs_synthetic* APIs. Not
all APIs are covered, that section should be extended. Unit tests for
basic tracefs_synthetic* APIs are added, to test the changes related to
dynamic events code in the library, related to synthetic events.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
utest/tracefs-utest.c | 95 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 95 insertions(+)
diff --git a/utest/tracefs-utest.c b/utest/tracefs-utest.c
index 75ac147..ac840d4 100644
--- a/utest/tracefs-utest.c
+++ b/utest/tracefs-utest.c
@@ -403,6 +403,100 @@ static struct tracefs_dynevent **get_dynevents_check(enum tracefs_dynevent_type
return devents;
}
+
+struct test_synth {
+ char *name;
+ char *start_system;
+ char *start_event;
+ char *end_system;
+ char *end_event;
+ char *start_match_field;
+ char *end_match_field;
+ char *match_name;
+};
+
+static void test_synth_compare(struct test_synth *synth, struct tracefs_dynevent **devents)
+{
+ enum tracefs_dynevent_type stype;
+ char *format;
+ char *event;
+ int i;
+
+ for (i = 0; devents && devents[i]; i++) {
+ stype = tracefs_dynevent_info(devents[i], NULL,
+ &event, NULL, NULL, &format);
+ CU_TEST(stype == TRACEFS_DYNEVENT_SYNTH);
+ CU_TEST(strcmp(event, synth[i].name) == 0);
+ if (synth[i].match_name) {
+ CU_TEST(strstr(format, synth[i].match_name) != NULL);
+ }
+ }
+ CU_TEST(devents[i] == NULL);
+}
+
+static void test_instance_syntetic(struct tracefs_instance *instance)
+{
+ struct test_synth sevents[] = {
+ {"synth_1", "sched", "sched_waking", "sched", "sched_switch", "pid", "next_pid", "pid_match"},
+ {"synth_2", "syscalls", "sys_enter_openat2", "syscalls", "sys_exit_openat2", "__syscall_nr", "__syscall_nr", "nr_match"},
+ };
+ int sevents_count = sizeof(sevents) / sizeof((sevents)[0]);
+ struct tracefs_dynevent **devents;
+ struct tracefs_synth **synth;
+ struct tep_handle *tep;
+ int ret;
+ int i;
+
+ synth = calloc(sevents_count + 1, sizeof(*synth));
+
+ tep = tracefs_local_events(NULL);
+ CU_TEST(tep != NULL);
+
+ /* kprobes APIs */
+ ret = tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_SYNTH, true);
+ CU_TEST(ret == 0);
+ get_dynevents_check(TRACEFS_DYNEVENT_SYNTH, 0);
+
+ for (i = 0; i < sevents_count; i++) {
+ synth[i] = tracefs_synth_alloc(tep, sevents[i].name,
+ sevents[i].start_system, sevents[i].start_event,
+ sevents[i].end_system, sevents[i].end_event,
+ sevents[i].start_match_field, sevents[i].end_match_field,
+ sevents[i].match_name);
+ CU_TEST(synth[i] != NULL);
+ }
+
+ get_dynevents_check(TRACEFS_DYNEVENT_SYNTH, 0);
+
+ for (i = 0; i < sevents_count; i++) {
+ ret = tracefs_synth_create(synth[i]);
+ CU_TEST(ret == 0);
+ }
+
+ devents = get_dynevents_check(TRACEFS_DYNEVENT_SYNTH, sevents_count);
+ CU_TEST(devents != NULL);
+ test_synth_compare(sevents, devents);
+ tracefs_dynevent_list_free(devents);
+
+ for (i = 0; i < sevents_count; i++) {
+ ret = tracefs_synth_destroy(synth[i]);
+ CU_TEST(ret == 0);
+ }
+
+ get_dynevents_check(TRACEFS_DYNEVENT_SYNTH, 0);
+
+ for (i = 0; i < sevents_count; i++)
+ tracefs_synth_free(synth[i]);
+
+ tep_free(tep);
+ free(synth);
+}
+
+static void test_synthetic(void)
+{
+ test_instance_syntetic(test_instance);
+}
+
static void test_trace_file(void)
{
const char *tmp = get_rand_str();
@@ -1525,4 +1619,5 @@ void test_tracefs_lib(void)
CU_add_test(suite, "ftrace marker",
test_ftrace_marker);
CU_add_test(suite, "kprobes", test_kprobes);
+ CU_add_test(suite, "syntetic events", test_synthetic);
}
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 10/12] libtracefs: Update kprobes man pages
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (8 preceding siblings ...)
2021-11-08 8:04 ` [PATCH v6 09/12] libtracefs: Add unit test for synthetic events Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:04 ` Tzvetomir Stoyanov (VMware)
2021-11-08 8:04 ` [PATCH v6 11/12] libtracefs: Document dynamic events APIs Tzvetomir Stoyanov (VMware)
2021-11-08 8:04 ` [PATCH v6 12/12] libtracefs: Do not clean sqlhist man page source Tzvetomir Stoyanov (VMware)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:04 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
As there are a lot of changes in the libtracefs kprobes APIs, the
documentation of the library should be updated.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
Documentation/libtracefs-kprobes.txt | 94 +++++++++++-----------------
Documentation/libtracefs.txt | 6 ++
2 files changed, 41 insertions(+), 59 deletions(-)
diff --git a/Documentation/libtracefs-kprobes.txt b/Documentation/libtracefs-kprobes.txt
index c10576e..4a4bf01 100644
--- a/Documentation/libtracefs-kprobes.txt
+++ b/Documentation/libtracefs-kprobes.txt
@@ -3,7 +3,8 @@ libtracefs(3)
NAME
----
-tracefs_kprobe_raw, tracefs_kretprobe_raw, tracefs_get_kprobes, tracefs_kprobe_info, tracefs_kprobe_clear_all, tracefs_kprobe_clear_probe - Create, list, and destroy kprobes
+tracefs_kprobe_alloc, tracefs_kretprobe_alloc, tracefs_kprobe_raw, tracefs_kretprobe_raw -
+Allocate, get, and create kprobes
SYNOPSIS
--------
@@ -11,18 +12,30 @@ SYNOPSIS
--
*#include <tracefs.h>*
-int tracefs_kprobe_raw(const char pass:[*]system, const char pass:[*]event, const char pass:[*]addr, const char pass:[*]format);
-int tracefs_kretprobe_raw(const char pass:[*]system, const char pass:[*]event, const char pass:[*]addr, const char pass:[*]format);
-char pass:[*]pass:[*]tracefs_get_kprobes(enum tracefs_kprobe_type type);
-enum tracefs_kprobe_type tracefs_kprobe_info(const char pass:[*]group, const char pass:[*]event,
- char pass:[*]pass:[*]type, char pass:[*]pass:[*]addr, char pass:[*]pass:[*]format);
-enum tracefs_kprobe_type tracefs_kprobe_type(const char pass:[*]group, const char pass:[*]event)
-int tracefs_kprobe_clear_all(bool force);
-int tracefs_kprobe_clear_probe(const char pass:[*]system, const char pass:[*]event, bool force);
+struct tracefs_dynevent pass:[*]
+*tracefs_kprobe_alloc*(const char pass:[*]_system_, const char pass:[*]_event_,
+ const char pass:[*]_addr_, const char pass:[*]_format_);
+struct tracefs_dynevent pass:[*]
+*tracefs_kretprobe_alloc*(const char pass:[*]_system_, const char pass:[*]_event_,
+ const char pass:[*]_addr_, const char pass:[*]_format_, unsigned int _max_);
+int *tracefs_kprobe_raw*(const char pass:[*]_system_, const char pass:[*]_event_,
+ const char pass:[*]_addr_, const char pass:[*]_format_);
+int *tracefs_kretprobe_raw*(const char pass:[*]_system_, const char pass:[*]_event_,
+ const char pass:[*]_addr_, const char pass:[*]_format_);
--
DESCRIPTION
-----------
+*tracefs_kprobe_alloc*() allocates a new kprobe context. The kbrobe is not configured in the system.
+The new kprobe will be in the _system_ group (or kprobes if _system_ is NULL) and have the name of
+_event_ (or _addr_ if _event_ is NULL). The kprobe will be inserted to _addr_ (function name, with
+or without offset, or a address), and the _format_ will define the format of the kprobe. See the
+Linux documentation file under: Documentation/trace/kprobetrace.rst
+
+*tracefs_kretprobe_alloc*() is the same as *tracefs_kprobe_alloc*, but allocates context for
+kretprobe. It has one additional parameter, which is optional, _max_ - maxactive count.
+See description of kretprobes in the Documentation/trace/kprobetrace.rst file.
+
*tracefs_kprobe_raw*() will create a kprobe event. If _system_ is NULL, then
the default "kprobes" is used for the group (event system). Otherwise if _system_
is specified then the kprobe will be created under the group by that name. The
@@ -36,55 +49,17 @@ document.
creates a kretprobe instead of a kprobe. The difference is also described
in the Linux kernel source in the Documentation/trace/kprobetrace.rst file.
-*tracefs_get_kprobes*() returns an array of strings (char pass:[*]) that contain
-the registered kprobes and kretprobes depending on the given _type_. If _type_ is
-TRACEFS_ALL_KPROBES, then all kprobes found are returned. If _type_ is
-TRACEFS_KPROBE, then only normal kprobes are returned. If _type_ is
-TRACEFS_KRETPROBE, then only kretprobes are returned.
-The names are in the "system/event" format.
-That is, one string holds both the kprobe's name as well as the group it is
-defined under. These strings are allocated and may be modified with the
-*strtok*(3) and *strtok_r*(3) functions. The string returned must be freed with
-*tracefs_list_free*(3).
-
-*tracefs_kprobe_info*() returns the type of the given kprobe. If _group_ is
-NULL, then the default "kprobes" is used. If _type_ is non NULL, then it will
-hold an allocated string that holds the type portion of the kprobe in the
-kprobe_events file (the content before the ":"). If _addr_ is non NULL, it will
-hold the address or function that the kprobe is attached to. If _format_ is non
-NULL, it will hold the format string of the kprobe. Note, that the content in
-_type_, _addr_, and _format_ must be freed with free(3) if they are set. Even
-in the case of an error, as they may hold information of what caused the error.
-
-*tracefs_kprobe_clear_all*() will try to remove all kprobes that have been
-registered. If the @force flag is set, it will then disable those kprobe events
-if they are enabled and then try to clear the kprobes.
-
-*tracefs_kprobe_clear_probe*() will try to clear specified kprobes. If _system_
-is NULL, then it will only clear the default kprobes under the "kprobes" group.
-If _event_ is NULL, it will clear all kprobes under the given _system_. If the
-_force_ flag is set, then it will disable the given kprobe events before clearing
-them.
-
RETURN VALUE
------------
-*tracefs_kprobe_raw*(), *tracefs_kretprobe_raw*(), *tracefs_kprobe_clear_all*(),
-and *tracefs_kprobe_clear_probe*() return 0 on success, or -1 on error.
-
-If a parsing error occurs on *tracefs_kprobe_raw*() or *tracefs_kretprobe_raw*()
-then *tracefs_error_last*(3) may be used to retrieve the error message explaining
-the parsing issue.
-
-*tracefs_get_kprobes*() returns an allocate string list of allocated strings
-on success that must be freed with *tracefs_list_free*(3) and returns
-NULL on error.
+*tracefs_kprobe_raw*() and *tracefs_kretprobe_raw*() return 0 on success, or -1 on error.
+If a parsing error occurs on *tracefs_kprobe_raw*() or *tracefs_kretprobe_raw*() then
+*tracefs_error_last*(3) may be used to retrieve the error message explaining the parsing issue.
-*tracefs_kprobe_info*() returns the type of the given kprobe. It returns
-TRACEFS_KPROBE for normal kprobes, TRACEFS_KRETPROBE for kretprobes, and
-on error, or if the kprobe is not found TRACEFS_ALL_KPROBES is returned.
-If _type_, _addr_, or _format_ are non NULL, they will contain allocated
-strings that must be freed by free(3) even in the case of error.
+The *tracefs_kprobe_alloc*() and *tracefs_kretprobe_alloc*() APIs return a pointer to an allocated
+tracefs_dynevent structure, describing the probe. This pointer must be freed by
+*tracefs_dynevent_free*(3). Note, this only allocates a descriptor representing the kprobe. It does
+not modify the running system.
ERRORS
------
@@ -96,9 +71,10 @@ The following errors are for all the above calls:
*ENOMEM* Memory allocation error.
-*tracefs_kprobe_raw*(), *tracefs_kretprobe_raw*() can fail with the following errors:
+*tracefs_kprobe_raw*(), *tracefs_kretprobe_raw*(), *tracefs_kprobe_alloc*(),
+and *tracefs_kretprobe_alloc*() can fail with the following errors:
-*EBADMSG* Either _addr_ or _format_ are NULL.
+*EBADMSG* if _addr_ is NULL.
*EINVAL* Most likely a parsing error occurred (use *tracefs_error_last*(3) to possibly
see what that error was).
@@ -217,7 +193,7 @@ int main (int argc, char **argv, char **env)
exit(-1);
}
- tracefs_kprobe_clear_probe(mykprobe, NULL, true);
+ tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
kprobe_create("open", "do_sys_openat2",
"file=+0($arg2):ustring flags=+0($arg3):x64 mode=+8($arg3):x64\n");
@@ -247,7 +223,7 @@ int main (int argc, char **argv, char **env)
} while (waitpid(pid, NULL, WNOHANG) != pid);
/* Will disable the events */
- tracefs_kprobe_clear_probe(mykprobe, NULL, true);
+ tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
tracefs_instance_destroy(instance);
tep_free(tep);
@@ -293,5 +269,5 @@ https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/
COPYING
-------
-Copyright \(C) 2020 VMware, Inc. Free use of this software is granted under
+Copyright \(C) 2021 VMware, Inc. Free use of this software is granted under
the terms of the GNU Public License (GPL).
diff --git a/Documentation/libtracefs.txt b/Documentation/libtracefs.txt
index 2c9eabd..430d02e 100644
--- a/Documentation/libtracefs.txt
+++ b/Documentation/libtracefs.txt
@@ -63,6 +63,12 @@ Writing data in the trace buffer:
Control library logs:
int *tracefs_set_loglevel*(enum tep_loglevel _level_);
+
+Kprobes and Kretprobes:
+ struct tracefs_dynevent pass:[*] *tracefs_kprobe_alloc*(const char pass:[*]_system_, const char pass:[*]_event_, const char pass:[*]_addr_, const char pass:[*]_format_);
+ struct tracefs_dynevent pass:[*] *tracefs_kretprobe_alloc*(const char pass:[*]_system_, const char pass:[*]_event_, const char pass:[*]_addr_, const char pass:[*]_format_, unsigned int _max_);
+ int *tracefs_kprobe_raw*(const char pass:[*]_system_, const char pass:[*]_event_, const char pass:[*]_addr_, const char pass:[*]_format_);
+ int *tracefs_kretprobe_raw*(const char pass:[*]_system_, const char pass:[*]_event_, const char pass:[*]_addr_, const char pass:[*]_format_);
--
DESCRIPTION
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v6 11/12] libtracefs: Document dynamic events APIs
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (9 preceding siblings ...)
2021-11-08 8:04 ` [PATCH v6 10/12] libtracefs: Update kprobes man pages Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:04 ` Tzvetomir Stoyanov (VMware)
2021-11-11 19:53 ` Steven Rostedt
2021-11-08 8:04 ` [PATCH v6 12/12] libtracefs: Do not clean sqlhist man page source Tzvetomir Stoyanov (VMware)
11 siblings, 1 reply; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:04 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
As a new set of APIs for ftrace dynamic events were added recently,
they must be documented. A new man page is added, describing these
APIs:
tracefs_dynevent_create();
tracefs_dynevent_destroy();
tracefs_dynevent_destroy_all();
tracefs_dynevent_free();
tracefs_dynevent_list_free();
tracefs_dynevent_get_all();
tracefs_dynevent_info();
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
Documentation/libtracefs-dynevents.txt | 266 +++++++++++++++++++++++++
Documentation/libtracefs.txt | 11 +
2 files changed, 277 insertions(+)
create mode 100644 Documentation/libtracefs-dynevents.txt
diff --git a/Documentation/libtracefs-dynevents.txt b/Documentation/libtracefs-dynevents.txt
new file mode 100644
index 0000000..95032ef
--- /dev/null
+++ b/Documentation/libtracefs-dynevents.txt
@@ -0,0 +1,266 @@
+libtracefs(3)
+=============
+
+NAME
+----
+tracefs_dynevent_create, tracefs_dynevent_destroy, tracefs_dynevent_destroy_all,
+tracefs_dynevent_free, tracefs_dynevent_list_free, tracefs_dynevent_get_all, tracefs_dynevent_info -
+Create, destroy, free and get dynamic events.
+
+SYNOPSIS
+--------
+[verse]
+--
+*#include <tracefs.h>*
+
+struct *tracefs_dynevent*;
+enum *tracefs_dynevent_type*;
+int *tracefs_dynevent_create*(struct tracefs_dynevent pass:[*]_devent_);
+int *tracefs_dynevent_destroy*(struct tracefs_dynevent pass:[*]_devent_, bool _force_);
+int *tracefs_dynevent_destroy_all*(unsigned int _types_, bool _force_);
+void *tracefs_dynevent_free*(struct tracefs_dynevent pass:[*]_devent_);
+void *tracefs_dynevent_list_free*(struct tracefs_dynevent pass:[*]pass:[*]_events_);
+struct tracefs_dynevent pass:[*]pass:[*]*tracefs_dynevent_get_all*(unsigned int _types_, const char pass:[*]_system_);
+enum tracefs_dynevent_type *tracefs_dynevent_info*(struct tracefs_dynevent pass:[*]_dynevent_, char pass:[*]pass:[*]_system_, char pass:[*]pass:[*]_event_, char pass:[*]pass:[*]_prefix_, char pass:[*]pass:[*]_addr_, char pass:[*]pass:[*]_format_);
+--
+
+DESCRIPTION
+-----------
+
+The *tracefs_dynevent_create*() function creates dynamic event _devent_ in the system.
+
+The *tracefs_dynevent_destroy*() function removes dynamic event _devent_ from the system. If _force_
+is true, the function will attempt to disable all events in all trace instances, before removing
+the dynamic event. The _devent_ context is not freed, use *tracefs_dynevent_free*() to free it.
+
+The *tracefs_dynevent_destroy_all*() function removes all dynamic events of given types from the
+system. The _types_ parameter is a type of specific dynamic event, or a bitmask of dynamic events
+types *tracefs_dynevent_type*, that will be removed. If _types_ is 0, dynamic events from all types
+will be removed. If _force_ is true, the function will attempt to disable all events in all trace
+instances, before removing the dynamic events.
+
+The *tracefs_dynevent_get_all*() function allocates and returns an array of pointers to dynamic
+events of given types that exist in the system. The last element of the array is a NULL pointer.
+The array must be freed with *tracefs_dynevent_list_free*(). If there are no events a NULL pointer is
+returned. The _types_ parameter is a type of specific dynamic event, or a bitmask of dynamic events
+types *tracefs_dynevent_type*, that will be retrieved. If _types_ is 0, dynamic events from all
+types will be retrieved.
+
+The *tracefs_dynevent_free*() function frees a dynamic event context _devent_.
+
+The *tracefs_dynevent_list_free*() function frees an array of pointers to dynamic event, returned
+by *tracefs_dynevent_get_all()* API.
+
+The *tracefs_dynevent_info*() function returns the type and information of a given dynamic event
+_dynevent_. If any of the _system_, _event_, _prefix_, _addr_ or _format_ arguments are not NULL,
+then strings are allocated and returned back via these arguments. The _system_ and _event_ holds the
+system and the name of the dynamic event. If _prefix_ is non NULL, then it will hold an allocated
+string that holds the prefix portion of the dynamic event (the content up to the ":", exluding it).
+If _addr_ is non NULL, it will hold the address or function that the dynamic event is attached to,
+if relevant for this event type. If _format_ is non NULL, it will hold the format string of the
+dynamic event. Note, that the content in _group_, _event_, _prefix_, _addr_, and _format_ must be
+freed with free(3) if they are set.
+
+RETURN VALUE
+------------
+
+*tracefs_dynevent_create*() returns 0 on success, or -1 on error. If a parsing error occurs then
+*tracefs_error_last*(3) may be used to retrieve the error message explaining the parsing issue.
+
+*tracefs_dynevent_destroy*() and *tracefs_dynevent_destroy_all*() return 0 on success, or -1 on
+error. If _force_ is enabled, the functions may fail on disabling the events.
+
+*tracefs_dynevent_get_all*() function returns allocated array of pointers to dynamic events, or NULL
+in case of an error or in case there are no events in the system. That array must be freed by
+*tracefs_dynevent_list_free*().
+
+*tracefs_dynevent_info*() returns the type of the given dynamic event or TRACEFS_DYNEVENT_UNKNOWN
+on error. If _system_, _event_, _prefix_, _addr_, or _format_ are non NULL, they will contain
+allocated strings that must be freed by free(3).
+
+ERRORS
+------
+The following errors are for all the above calls:
+
+*EPERM* Not run as root user
+
+*ENODEV* dynamic events of requested type are not configured for the running kernel.
+
+*ENOMEM* Memory allocation error.
+
+*tracefs_dynevent_create*() can fail with the following errors:
+
+*EINVAL* Most likely a parsing error occurred (use *tracefs_error_last*(3) to possibly
+ see what that error was).
+
+Other errors may also happen caused by internal system calls.
+
+EXAMPLE
+-------
+[source,c]
+--
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/wait.h>
+
+#include <tracefs/tracefs.h>
+
+static struct tep_event *open_event;
+static struct tep_format_field *file_field;
+
+static struct tep_event *openret_event;
+static struct tep_format_field *ret_field;
+
+static int callback(struct tep_event *event, struct tep_record *record,
+ int cpu, void *data)
+{
+ struct trace_seq seq;
+
+ trace_seq_init(&seq);
+ tep_print_event(event->tep, &seq, record, "%d-%s: ", TEP_PRINT_PID, TEP_PRINT_COMM);
+
+ if (event->id == open_event->id) {
+ trace_seq_puts(&seq, "open file='");
+ tep_print_field(&seq, record->data, file_field);
+ trace_seq_puts(&seq, "'\n");
+ } else if (event->id == openret_event->id) {
+ unsigned long long ret;
+ tep_read_number_field(ret_field, record->data, &ret);
+ trace_seq_printf(&seq, "open ret=%lld\n", ret);
+ } else {
+ goto out;
+ }
+
+ trace_seq_terminate(&seq);
+ trace_seq_do_printf(&seq);
+out:
+ trace_seq_destroy(&seq);
+
+ return 0;
+}
+
+static pid_t run_exec(char **argv, char **env)
+{
+ pid_t pid;
+
+ pid = fork();
+ if (pid)
+ return pid;
+
+ execve(argv[0], argv, env);
+ perror("exec");
+ exit(-1);
+}
+
+const char *mykprobe = "my_kprobes";
+
+int main (int argc, char **argv, char **env)
+{
+ struct tracefs_dynevent *kprobe, *kretprobe;
+ const char *sysnames[] = { mykprobe, NULL };
+ struct tracefs_instance *instance;
+ struct tep_handle *tep;
+ pid_t pid;
+
+ if (argc < 2) {
+ printf("usage: %s command\n", argv[0]);
+ exit(-1);
+ }
+
+ instance = tracefs_instance_create("exec_open");
+ if (!instance) {
+ perror("creating instance");
+ exit(-1);
+ }
+
+ tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
+
+ kprobe = tracefs_kprobe_alloc(mykprobe, "open", "do_sys_openat2",
+ "file=+0($arg2):ustring flags=+0($arg3):x64 mode=+8($arg3):x64\n");
+ kretprobe = tracefs_kretprobe_alloc(mykprobe, "openret", "do_sys_openat2", "ret=%ax", 0);
+ if (!kprobe || !kretprobe) {
+ perror("allocating dynamic events");
+ exit(-1);
+ }
+
+ if (tracefs_dynevent_create(kprobe) || tracefs_dynevent_create(kretprobe)){
+ err = tracefs_error_last(NULL);
+ perror("Failed to create kprobes:");
+ if (err && strlen(err))
+ fprintf(stderr, "%s\n", err);
+ exit(-1);
+ }
+
+ tep = tracefs_local_events_system(NULL, sysnames);
+ if (!tep) {
+ perror("reading events");
+ exit(-1);
+ }
+ open_event = tep_find_event_by_name(tep, mykprobe, "open");
+ file_field = tep_find_field(open_event, "file");
+
+ openret_event = tep_find_event_by_name(tep, mykprobe, "openret");
+ ret_field = tep_find_field(openret_event, "ret");
+
+ tracefs_event_enable(instance, mykprobe, NULL);
+ pid = run_exec(&argv[1], env);
+
+ /* Let the child start to run */
+ sched_yield();
+
+ do {
+ tracefs_load_cmdlines(NULL, tep);
+ tracefs_iterate_raw_events(tep, instance, NULL, 0, callback, NULL);
+ } while (waitpid(pid, NULL, WNOHANG) != pid);
+
+ /* Will disable the events */
+ tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
+ tracefs_dynevent_free(kprobe);
+ tracefs_dynevent_free(kretprobe);
+ tracefs_instance_destroy(instance);
+ tep_free(tep);
+
+ return 0;
+}
+--
+
+FILES
+-----
+[verse]
+--
+*tracefs.h*
+ Header file to include in order to have access to the library APIs.
+*-ltracefs*
+ Linker switch to add when building a program that uses the library.
+--
+
+SEE ALSO
+--------
+_libtracefs(3)_,
+_libtraceevent(3)_,
+_trace-cmd(1)_
+
+AUTHOR
+------
+[verse]
+--
+*Steven Rostedt* <rostedt@goodmis.org>
+*Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>
+*Yordan Karadzhov* <y.karadz@gmail.com>
+--
+REPORTING BUGS
+--------------
+Report bugs to <linux-trace-devel@vger.kernel.org>
+
+LICENSE
+-------
+libtracefs is Free Software licensed under the GNU LGPL 2.1
+
+RESOURCES
+---------
+https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/
+
+COPYING
+-------
+Copyright \(C) 2021 VMware, Inc. Free use of this software is granted under
+the terms of the GNU Public License (GPL).
diff --git a/Documentation/libtracefs.txt b/Documentation/libtracefs.txt
index 430d02e..6850860 100644
--- a/Documentation/libtracefs.txt
+++ b/Documentation/libtracefs.txt
@@ -64,6 +64,17 @@ Writing data in the trace buffer:
Control library logs:
int *tracefs_set_loglevel*(enum tep_loglevel _level_);
+Dynamic event generic APIs:
+ struct *tracefs_dynevent*;
+ enum *tracefs_dynevent_type*;
+ int *tracefs_dynevent_create*(struct tracefs_dynevent pass:[*]_devent_);
+ int *tracefs_dynevent_destroy*(struct tracefs_dynevent pass:[*]_devent_, bool _force_);
+ int *tracefs_dynevent_destroy_all*(unsigned int _types_, bool _force_);
+ void *tracefs_dynevent_free*(struct tracefs_dynevent pass:[*]_devent_);
+ void *tracefs_dynevent_list_free*(struct tracefs_dynevent pass:[*]pass:[*]_events_);
+ struct tracefs_dynevent pass:[*]pass:[*]*tracefs_dynevent_get_all*(unsigned int _types_, const char pass:[*]_system_);
+ enum tracefs_dynevent_type *tracefs_dynevent_info*(struct tracefs_dynevent pass:[*]_dynevent_, char pass:[*]pass:[*]_system_, char pass:[*]pass:[*]_event_, char pass:[*]pass:[*]_prefix_, char pass:[*]pass:[*]_addr_, char pass:[*]pass:[*]_format_);
+
Kprobes and Kretprobes:
struct tracefs_dynevent pass:[*] *tracefs_kprobe_alloc*(const char pass:[*]_system_, const char pass:[*]_event_, const char pass:[*]_addr_, const char pass:[*]_format_);
struct tracefs_dynevent pass:[*] *tracefs_kretprobe_alloc*(const char pass:[*]_system_, const char pass:[*]_event_, const char pass:[*]_addr_, const char pass:[*]_format_, unsigned int _max_);
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* Re: [PATCH v6 11/12] libtracefs: Document dynamic events APIs
2021-11-08 8:04 ` [PATCH v6 11/12] libtracefs: Document dynamic events APIs Tzvetomir Stoyanov (VMware)
@ 2021-11-11 19:53 ` Steven Rostedt
0 siblings, 0 replies; 17+ messages in thread
From: Steven Rostedt @ 2021-11-11 19:53 UTC (permalink / raw)
To: Tzvetomir Stoyanov (VMware); +Cc: y.karadz, linux-trace-devel
On Mon, 8 Nov 2021 10:04:03 +0200
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:
> +ERRORS
> +------
> +The following errors are for all the above calls:
> +
> +*EPERM* Not run as root user
We should probably stop stating this. Because starting with 5.16, you do
not need to be root. You only need to be in the group that allows tracing.
# groupadd tracing
# usermod -a tracing rostedt
# mount -t tracefs nodev /sys/krenel/tracing
# chmod 770 /sys/kernel/tracing
# chmod g+w /sys/kernel/tracing/*
# chgrp -R tracing /sys/kernel/tracing
And now my "rostedt" user can have full access to tracing. We need to
update trace-cmd to allow this too.
But this is outside the scope of this patch series.
> +
> +*ENODEV* dynamic events of requested type are not configured for the running kernel.
> +
> +*ENOMEM* Memory allocation error.
> +
> +*tracefs_dynevent_create*() can fail with the following errors:
> +
> +*EINVAL* Most likely a parsing error occurred (use *tracefs_error_last*(3) to possibly
> + see what that error was).
> +
> +Other errors may also happen caused by internal system calls.
> +
> +EXAMPLE
> +-------
> +[source,c]
> +--
> +#include <stdlib.h>
> +#include <unistd.h>
> +#include <sys/wait.h>
> +
> +#include <tracefs/tracefs.h>
> +
> +static struct tep_event *open_event;
> +static struct tep_format_field *file_field;
> +
> +static struct tep_event *openret_event;
> +static struct tep_format_field *ret_field;
> +
> +static int callback(struct tep_event *event, struct tep_record *record,
> + int cpu, void *data)
> +{
> + struct trace_seq seq;
> +
> + trace_seq_init(&seq);
> + tep_print_event(event->tep, &seq, record, "%d-%s: ", TEP_PRINT_PID, TEP_PRINT_COMM);
> +
> + if (event->id == open_event->id) {
> + trace_seq_puts(&seq, "open file='");
> + tep_print_field(&seq, record->data, file_field);
> + trace_seq_puts(&seq, "'\n");
> + } else if (event->id == openret_event->id) {
> + unsigned long long ret;
> + tep_read_number_field(ret_field, record->data, &ret);
> + trace_seq_printf(&seq, "open ret=%lld\n", ret);
> + } else {
> + goto out;
> + }
> +
> + trace_seq_terminate(&seq);
> + trace_seq_do_printf(&seq);
> +out:
> + trace_seq_destroy(&seq);
> +
> + return 0;
> +}
> +
> +static pid_t run_exec(char **argv, char **env)
> +{
> + pid_t pid;
> +
> + pid = fork();
> + if (pid)
> + return pid;
> +
> + execve(argv[0], argv, env);
> + perror("exec");
> + exit(-1);
> +}
> +
> +const char *mykprobe = "my_kprobes";
> +
> +int main (int argc, char **argv, char **env)
> +{
> + struct tracefs_dynevent *kprobe, *kretprobe;
> + const char *sysnames[] = { mykprobe, NULL };
> + struct tracefs_instance *instance;
> + struct tep_handle *tep;
> + pid_t pid;
> +
> + if (argc < 2) {
> + printf("usage: %s command\n", argv[0]);
> + exit(-1);
> + }
> +
> + instance = tracefs_instance_create("exec_open");
> + if (!instance) {
> + perror("creating instance");
> + exit(-1);
> + }
> +
> + tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
> +
> + kprobe = tracefs_kprobe_alloc(mykprobe, "open", "do_sys_openat2",
> + "file=+0($arg2):ustring flags=+0($arg3):x64 mode=+8($arg3):x64\n");
> + kretprobe = tracefs_kretprobe_alloc(mykprobe, "openret", "do_sys_openat2", "ret=%ax", 0);
> + if (!kprobe || !kretprobe) {
> + perror("allocating dynamic events");
> + exit(-1);
> + }
> +
> + if (tracefs_dynevent_create(kprobe) || tracefs_dynevent_create(kretprobe)){
Missing:
char *err;
I can add it.
-- Steve
> + err = tracefs_error_last(NULL);
> + perror("Failed to create kprobes:");
> + if (err && strlen(err))
> + fprintf(stderr, "%s\n", err);
> + exit(-1);
> + }
> +
> + tep = tracefs_local_events_system(NULL, sysnames);
> + if (!tep) {
> + perror("reading events");
> + exit(-1);
> + }
> + open_event = tep_find_event_by_name(tep, mykprobe, "open");
> + file_field = tep_find_field(open_event, "file");
> +
> + openret_event = tep_find_event_by_name(tep, mykprobe, "openret");
> + ret_field = tep_find_field(openret_event, "ret");
> +
> + tracefs_event_enable(instance, mykprobe, NULL);
> + pid = run_exec(&argv[1], env);
> +
> + /* Let the child start to run */
> + sched_yield();
> +
> + do {
> + tracefs_load_cmdlines(NULL, tep);
> + tracefs_iterate_raw_events(tep, instance, NULL, 0, callback, NULL);
> + } while (waitpid(pid, NULL, WNOHANG) != pid);
> +
> + /* Will disable the events */
> + tracefs_dynevent_destroy_all(TRACEFS_DYNEVENT_KPROBE | TRACEFS_DYNEVENT_KRETPROBE, true);
> + tracefs_dynevent_free(kprobe);
> + tracefs_dynevent_free(kretprobe);
> + tracefs_instance_destroy(instance);
> + tep_free(tep);
> +
> + return 0;
> +}
> +--
> +
> +FILES
> +-----
> +[verse]
> +--
> +*tracefs.h*
> + Header file to include in order to have access to the library APIs.
> +*-ltracefs*
> + Linker switch to add when building a program that uses the library.
> +--
> +
> +SEE ALSO
> +--------
> +_libtracefs(3)_,
> +_libtraceevent(3)_,
> +_trace-cmd(1)_
> +
> +AUTHOR
> +------
> +[verse]
> +--
> +*Steven Rostedt* <rostedt@goodmis.org>
> +*Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>
> +*Yordan Karadzhov* <y.karadz@gmail.com>
> +--
> +REPORTING BUGS
> +--------------
> +Report bugs to <linux-trace-devel@vger.kernel.org>
> +
> +LICENSE
> +-------
> +libtracefs is Free Software licensed under the GNU LGPL 2.1
> +
> +RESOURCES
> +---------
> +https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/
> +
> +COPYING
> +-------
> +Copyright \(C) 2021 VMware, Inc. Free use of this software is granted under
> +the terms of the GNU Public License (GPL).
> diff --git a/Documentation/libtracefs.txt b/Documentation/libtracefs.txt
> index 430d02e..6850860 100644
> --- a/Documentation/libtracefs.txt
> +++ b/Documentation/libtracefs.txt
> @@ -64,6 +64,17 @@ Writing data in the trace buffer:
> Control library logs:
> int *tracefs_set_loglevel*(enum tep_loglevel _level_);
>
> +Dynamic event generic APIs:
> + struct *tracefs_dynevent*;
> + enum *tracefs_dynevent_type*;
> + int *tracefs_dynevent_create*(struct tracefs_dynevent pass:[*]_devent_);
> + int *tracefs_dynevent_destroy*(struct tracefs_dynevent pass:[*]_devent_, bool _force_);
> + int *tracefs_dynevent_destroy_all*(unsigned int _types_, bool _force_);
> + void *tracefs_dynevent_free*(struct tracefs_dynevent pass:[*]_devent_);
> + void *tracefs_dynevent_list_free*(struct tracefs_dynevent pass:[*]pass:[*]_events_);
> + struct tracefs_dynevent pass:[*]pass:[*]*tracefs_dynevent_get_all*(unsigned int _types_, const char pass:[*]_system_);
> + enum tracefs_dynevent_type *tracefs_dynevent_info*(struct tracefs_dynevent pass:[*]_dynevent_, char pass:[*]pass:[*]_system_, char pass:[*]pass:[*]_event_, char pass:[*]pass:[*]_prefix_, char pass:[*]pass:[*]_addr_, char pass:[*]pass:[*]_format_);
> +
> Kprobes and Kretprobes:
> struct tracefs_dynevent pass:[*] *tracefs_kprobe_alloc*(const char pass:[*]_system_, const char pass:[*]_event_, const char pass:[*]_addr_, const char pass:[*]_format_);
> struct tracefs_dynevent pass:[*] *tracefs_kretprobe_alloc*(const char pass:[*]_system_, const char pass:[*]_event_, const char pass:[*]_addr_, const char pass:[*]_format_, unsigned int _max_);
^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH v6 12/12] libtracefs: Do not clean sqlhist man page source
2021-11-08 8:03 [PATCH v6 00/12] libtracefs dynamic events support Tzvetomir Stoyanov (VMware)
` (10 preceding siblings ...)
2021-11-08 8:04 ` [PATCH v6 11/12] libtracefs: Document dynamic events APIs Tzvetomir Stoyanov (VMware)
@ 2021-11-08 8:04 ` Tzvetomir Stoyanov (VMware)
11 siblings, 0 replies; 17+ messages in thread
From: Tzvetomir Stoyanov (VMware) @ 2021-11-08 8:04 UTC (permalink / raw)
To: rostedt, y.karadz; +Cc: linux-trace-devel
The "make doc_clean" command assumes that all *.1 files are being
generated with "make doc" command and removes all of them. This
assumption is wrong, as the sources of man pages from section one
have prefix "*.txt.1" and must not be removed. A more precise filtering
is added, so only files generated during "make doc" are removed.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
Documentation/Makefile | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/Documentation/Makefile b/Documentation/Makefile
index 0c00505..92a67aa 100644
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@ -197,7 +197,8 @@ endif
CLEAN_FILES = \
$(MAN_XML) $(addsuffix +,$(MAN_XML)) \
$(MAN_HTML) $(addsuffix +,$(MAN_HTML)) \
- $(DOC_MAN3) *.3 *.1 *.m
+ $(filter-out $(MAN1_TEXT),$(wildcard *.1)) \
+ $(DOC_MAN3) *.3 *.m
clean:
$(Q) $(RM) $(CLEAN_FILES)
--
2.31.1
^ permalink raw reply related [flat|nested] 17+ messages in thread