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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-20 11:19:48 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-20 11:19:48 -0700
commit45979a956b92c9bab652a2c4a5c39d8f94f6df2c (patch)
treeb13d28f9069a6acd9b02277063871fbeec5e5a95 /kernel/trace
parent3207598ab00e0fb06c8d73c9ae567afa4847e70e (diff)
parentb78b94b82122208902c0f83805e614e1239f9893 (diff)
downloadlinux-45979a956b92c9bab652a2c4a5c39d8f94f6df2c.tar.bz2
Merge tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt: - Addition of multiprobes to kprobe and uprobe events (allows for more than one probe attached to the same location) - Addition of adding immediates to probe parameters - Clean up of the recordmcount.c code. This brings us closer to merging recordmcount into objtool, and reuse code. - Other small clean ups * tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits) selftests/ftrace: Update kprobe event error testcase tracing/probe: Reject exactly same probe event tracing/probe: Fix to allow user to enable events on unloaded modules selftests/ftrace: Select an existing function in kprobe_eventname test tracing/kprobe: Fix NULL pointer access in trace_porbe_unlink() tracing: Make sure variable reference alias has correct var_ref_idx tracing: Be more clever when dumping hex in __print_hex() ftrace: Simplify ftrace hash lookup code in clear_func_from_hash() tracing: Add "gfp_t" support in synthetic_events tracing: Rename tracing_reset() to tracing_reset_cpu() tracing: Document the stack trace algorithm in the comments tracing/arm64: Have max stack tracer handle the case of return address after data recordmcount: Clarify what cleanup() does recordmcount: Remove redundant cleanup() calls recordmcount: Kernel style formatting recordmcount: Kernel style function signature formatting recordmcount: Rewrite error/success handling selftests/ftrace: Add syntax error test for multiprobe selftests/ftrace: Add syntax error test for immediates selftests/ftrace: Add a testcase for kprobe multiprobe event ...
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/ftrace.c6
-rw-r--r--kernel/trace/trace.c14
-rw-r--r--kernel/trace/trace.h1
-rw-r--r--kernel/trace/trace_dynevent.c10
-rw-r--r--kernel/trace/trace_dynevent.h7
-rw-r--r--kernel/trace/trace_events_hist.c25
-rw-r--r--kernel/trace/trace_kprobe.c268
-rw-r--r--kernel/trace/trace_output.c6
-rw-r--r--kernel/trace/trace_probe.c178
-rw-r--r--kernel/trace/trace_probe.h68
-rw-r--r--kernel/trace/trace_stack.c112
-rw-r--r--kernel/trace/trace_uprobe.c299
12 files changed, 818 insertions, 176 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 356b848c697a..62a50bf399d6 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -6036,11 +6036,7 @@ clear_func_from_hash(struct ftrace_init_func *func, struct ftrace_hash *hash)
{
struct ftrace_func_entry *entry;
- if (ftrace_hash_empty(hash))
- return;
-
- entry = __ftrace_lookup_ip(hash, func->ip);
-
+ entry = ftrace_lookup_ip(hash, func->ip);
/*
* Do not allow this rec to match again.
* Yeah, it may waste some memory, but will be removed
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 947ba433865f..252f79c435f8 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1854,7 +1854,7 @@ int __init register_tracer(struct tracer *type)
return ret;
}
-void tracing_reset(struct trace_buffer *buf, int cpu)
+static void tracing_reset_cpu(struct trace_buffer *buf, int cpu)
{
struct ring_buffer *buffer = buf->buffer;
@@ -4251,7 +4251,7 @@ static int tracing_open(struct inode *inode, struct file *file)
if (cpu == RING_BUFFER_ALL_CPUS)
tracing_reset_online_cpus(trace_buf);
else
- tracing_reset(trace_buf, cpu);
+ tracing_reset_cpu(trace_buf, cpu);
}
if (file->f_mode & FMODE_READ) {
@@ -4815,15 +4815,15 @@ static const char readme_msg[] =
#endif
#endif /* CONFIG_STACK_TRACER */
#ifdef CONFIG_DYNAMIC_EVENTS
- " dynamic_events\t\t- Add/remove/show the generic dynamic events\n"
+ " dynamic_events\t\t- Create/append/remove/show the generic dynamic events\n"
"\t\t\t Write into this file to define/undefine new trace events.\n"
#endif
#ifdef CONFIG_KPROBE_EVENTS
- " kprobe_events\t\t- Add/remove/show the kernel dynamic events\n"
+ " kprobe_events\t\t- Create/append/remove/show the kernel dynamic events\n"
"\t\t\t Write into this file to define/undefine new trace events.\n"
#endif
#ifdef CONFIG_UPROBE_EVENTS
- " uprobe_events\t\t- Add/remove/show the userspace dynamic events\n"
+ " uprobe_events\t\t- Create/append/remove/show the userspace dynamic events\n"
"\t\t\t Write into this file to define/undefine new trace events.\n"
#endif
#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS)
@@ -4848,7 +4848,7 @@ static const char readme_msg[] =
#else
"\t $stack<index>, $stack, $retval, $comm,\n"
#endif
- "\t +|-[u]<offset>(<fetcharg>)\n"
+ "\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n"
"\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string, symbol,\n"
"\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n"
"\t <type>\\[<array-size>\\]\n"
@@ -6742,7 +6742,7 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
tracing_reset_online_cpus(&tr->max_buffer);
else
- tracing_reset(&tr->max_buffer, iter->cpu_file);
+ tracing_reset_cpu(&tr->max_buffer, iter->cpu_file);
}
break;
}
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 005f08629b8b..26b0a08f3c7d 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -677,7 +677,6 @@ trace_buffer_iter(struct trace_iterator *iter, int cpu)
int tracer_init(struct tracer *t, struct trace_array *tr);
int tracing_is_enabled(void);
-void tracing_reset(struct trace_buffer *buf, int cpu);
void tracing_reset_online_cpus(struct trace_buffer *buf);
void tracing_reset_current(int cpu);
void tracing_reset_all_online_cpus(void);
diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
index fa100ed3b4de..a41fed46c285 100644
--- a/kernel/trace/trace_dynevent.c
+++ b/kernel/trace/trace_dynevent.c
@@ -47,6 +47,7 @@ int dyn_event_release(int argc, char **argv, struct dyn_event_operations *type)
return -EINVAL;
event++;
}
+ argc--; argv++;
p = strchr(event, '/');
if (p) {
@@ -61,10 +62,13 @@ int dyn_event_release(int argc, char **argv, struct dyn_event_operations *type)
for_each_dyn_event_safe(pos, n) {
if (type && type != pos->ops)
continue;
- if (pos->ops->match(system, event, pos)) {
- ret = pos->ops->free(pos);
+ if (!pos->ops->match(system, event,
+ argc, (const char **)argv, pos))
+ continue;
+
+ ret = pos->ops->free(pos);
+ if (ret)
break;
- }
}
mutex_unlock(&event_mutex);
diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h
index 8c334064e4d6..46898138d2df 100644
--- a/kernel/trace/trace_dynevent.h
+++ b/kernel/trace/trace_dynevent.h
@@ -31,8 +31,9 @@ struct dyn_event;
* @is_busy: Check whether given event is busy so that it can not be deleted.
* Return true if it is busy, otherwides false.
* @free: Delete the given event. Return 0 if success, otherwides error.
- * @match: Check whether given event and system name match this event.
- * Return true if it matches, otherwides false.
+ * @match: Check whether given event and system name match this event. The argc
+ * and argv is used for exact match. Return true if it matches, otherwides
+ * false.
*
* Except for @create, these methods are called under holding event_mutex.
*/
@@ -43,7 +44,7 @@ struct dyn_event_operations {
bool (*is_busy)(struct dyn_event *ev);
int (*free)(struct dyn_event *ev);
bool (*match)(const char *system, const char *event,
- struct dyn_event *ev);
+ int argc, const char **argv, struct dyn_event *ev);
};
/* Register new dyn_event type -- must be called at first */
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index ca6b0dff60c5..9468bd8d44a2 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -13,6 +13,10 @@
#include <linux/rculist.h>
#include <linux/tracefs.h>
+/* for gfp flag names */
+#include <linux/trace_events.h>
+#include <trace/events/mmflags.h>
+
#include "tracing_map.h"
#include "trace.h"
#include "trace_dynevent.h"
@@ -374,7 +378,7 @@ static int synth_event_show(struct seq_file *m, struct dyn_event *ev);
static int synth_event_release(struct dyn_event *ev);
static bool synth_event_is_busy(struct dyn_event *ev);
static bool synth_event_match(const char *system, const char *event,
- struct dyn_event *ev);
+ int argc, const char **argv, struct dyn_event *ev);
static struct dyn_event_operations synth_event_ops = {
.create = synth_event_create,
@@ -422,7 +426,7 @@ static bool synth_event_is_busy(struct dyn_event *ev)
}
static bool synth_event_match(const char *system, const char *event,
- struct dyn_event *ev)
+ int argc, const char **argv, struct dyn_event *ev)
{
struct synth_event *sev = to_synth_event(ev);
@@ -752,6 +756,8 @@ static int synth_field_size(char *type)
size = sizeof(unsigned long);
else if (strcmp(type, "pid_t") == 0)
size = sizeof(pid_t);
+ else if (strcmp(type, "gfp_t") == 0)
+ size = sizeof(gfp_t);
else if (synth_field_is_string(type))
size = synth_field_string_size(type);
@@ -792,6 +798,8 @@ static const char *synth_field_fmt(char *type)
fmt = "%lu";
else if (strcmp(type, "pid_t") == 0)
fmt = "%d";
+ else if (strcmp(type, "gfp_t") == 0)
+ fmt = "%x";
else if (synth_field_is_string(type))
fmt = "%s";
@@ -834,9 +842,20 @@ static enum print_line_t print_synth_event(struct trace_iterator *iter,
i == se->n_fields - 1 ? "" : " ");
n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
} else {
+ struct trace_print_flags __flags[] = {
+ __def_gfpflag_names, {-1, NULL} };
+
trace_seq_printf(s, print_fmt, se->fields[i]->name,
entry->fields[n_u64],
i == se->n_fields - 1 ? "" : " ");
+
+ if (strcmp(se->fields[i]->type, "gfp_t") == 0) {
+ trace_seq_puts(s, " (");
+ trace_print_flags_seq(s, "|",
+ entry->fields[n_u64],
+ __flags);
+ trace_seq_putc(s, ')');
+ }
n_u64++;
}
}
@@ -2785,6 +2804,8 @@ static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
return NULL;
}
+ alias->var_ref_idx = var_ref->var_ref_idx;
+
return alias;
}
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 9d483ad9bb6c..a6697e28ddda 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -39,7 +39,7 @@ static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev);
static int trace_kprobe_release(struct dyn_event *ev);
static bool trace_kprobe_is_busy(struct dyn_event *ev);
static bool trace_kprobe_match(const char *system, const char *event,
- struct dyn_event *ev);
+ int argc, const char **argv, struct dyn_event *ev);
static struct dyn_event_operations trace_kprobe_ops = {
.create = trace_kprobe_create,
@@ -137,13 +137,36 @@ static bool trace_kprobe_is_busy(struct dyn_event *ev)
return trace_probe_is_enabled(&tk->tp);
}
+static bool trace_kprobe_match_command_head(struct trace_kprobe *tk,
+ int argc, const char **argv)
+{
+ char buf[MAX_ARGSTR_LEN + 1];
+
+ if (!argc)
+ return true;
+
+ if (!tk->symbol)
+ snprintf(buf, sizeof(buf), "0x%p", tk->rp.kp.addr);
+ else if (tk->rp.kp.offset)
+ snprintf(buf, sizeof(buf), "%s+%u",
+ trace_kprobe_symbol(tk), tk->rp.kp.offset);
+ else
+ snprintf(buf, sizeof(buf), "%s", trace_kprobe_symbol(tk));
+ if (strcmp(buf, argv[0]))
+ return false;
+ argc--; argv++;
+
+ return trace_probe_match_command_args(&tk->tp, argc, argv);
+}
+
static bool trace_kprobe_match(const char *system, const char *event,
- struct dyn_event *ev)
+ int argc, const char **argv, struct dyn_event *ev)
{
struct trace_kprobe *tk = to_trace_kprobe(ev);
return strcmp(trace_probe_name(&tk->tp), event) == 0 &&
- (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0);
+ (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) &&
+ trace_kprobe_match_command_head(tk, argc, argv);
}
static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
@@ -180,20 +203,33 @@ unsigned long trace_kprobe_address(struct trace_kprobe *tk)
return addr;
}
+static nokprobe_inline struct trace_kprobe *
+trace_kprobe_primary_from_call(struct trace_event_call *call)
+{
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return NULL;
+
+ return container_of(tp, struct trace_kprobe, tp);
+}
+
bool trace_kprobe_on_func_entry(struct trace_event_call *call)
{
- struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
+ struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
- return kprobe_on_func_entry(tk->rp.kp.addr,
+ return tk ? kprobe_on_func_entry(tk->rp.kp.addr,
tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name,
- tk->rp.kp.addr ? 0 : tk->rp.kp.offset);
+ tk->rp.kp.addr ? 0 : tk->rp.kp.offset) : false;
}
bool trace_kprobe_error_injectable(struct trace_event_call *call)
{
- struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
+ struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
- return within_error_injection_list(trace_kprobe_address(tk));
+ return tk ? within_error_injection_list(trace_kprobe_address(tk)) :
+ false;
}
static int register_kprobe_event(struct trace_kprobe *tk);
@@ -291,32 +327,68 @@ static inline int __enable_trace_kprobe(struct trace_kprobe *tk)
return ret;
}
+static void __disable_trace_kprobe(struct trace_probe *tp)
+{
+ struct trace_probe *pos;
+ struct trace_kprobe *tk;
+
+ list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+ tk = container_of(pos, struct trace_kprobe, tp);
+ if (!trace_kprobe_is_registered(tk))
+ continue;
+ if (trace_kprobe_is_return(tk))
+ disable_kretprobe(&tk->rp);
+ else
+ disable_kprobe(&tk->rp.kp);
+ }
+}
+
/*
* Enable trace_probe
* if the file is NULL, enable "perf" handler, or enable "trace" handler.
*/
-static int
-enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
+static int enable_trace_kprobe(struct trace_event_call *call,
+ struct trace_event_file *file)
{
- bool enabled = trace_probe_is_enabled(&tk->tp);
+ struct trace_probe *pos, *tp;
+ struct trace_kprobe *tk;
+ bool enabled;
int ret = 0;
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENODEV;
+ enabled = trace_probe_is_enabled(tp);
+
+ /* This also changes "enabled" state */
if (file) {
- ret = trace_probe_add_file(&tk->tp, file);
+ ret = trace_probe_add_file(tp, file);
if (ret)
return ret;
} else
- trace_probe_set_flag(&tk->tp, TP_FLAG_PROFILE);
+ trace_probe_set_flag(tp, TP_FLAG_PROFILE);
if (enabled)
return 0;
- ret = __enable_trace_kprobe(tk);
+ list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+ tk = container_of(pos, struct trace_kprobe, tp);
+ if (trace_kprobe_has_gone(tk))
+ continue;
+ ret = __enable_trace_kprobe(tk);
+ if (ret)
+ break;
+ enabled = true;
+ }
+
if (ret) {
+ /* Failed to enable one of them. Roll back all */
+ if (enabled)
+ __disable_trace_kprobe(tp);
if (file)
- trace_probe_remove_file(&tk->tp, file);
+ trace_probe_remove_file(tp, file);
else
- trace_probe_clear_flag(&tk->tp, TP_FLAG_PROFILE);
+ trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
}
return ret;
@@ -326,11 +398,14 @@ enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
* Disable trace_probe
* if the file is NULL, disable "perf" handler, or disable "trace" handler.
*/
-static int
-disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
+static int disable_trace_kprobe(struct trace_event_call *call,
+ struct trace_event_file *file)
{
- struct trace_probe *tp = &tk->tp;
- int ret = 0;
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENODEV;
if (file) {
if (!trace_probe_get_file_link(tp, file))
@@ -341,12 +416,8 @@ disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
} else
trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
- if (!trace_probe_is_enabled(tp) && trace_kprobe_is_registered(tk)) {
- if (trace_kprobe_is_return(tk))
- disable_kretprobe(&tk->rp);
- else
- disable_kprobe(&tk->rp.kp);
- }
+ if (!trace_probe_is_enabled(tp))
+ __disable_trace_kprobe(tp);
out:
if (file)
@@ -358,7 +429,7 @@ disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
*/
trace_probe_remove_file(tp, file);
- return ret;
+ return 0;
}
#if defined(CONFIG_KPROBES_ON_FTRACE) && \
@@ -437,6 +508,10 @@ static void __unregister_trace_kprobe(struct trace_kprobe *tk)
/* Unregister a trace_probe and probe_event */
static int unregister_trace_kprobe(struct trace_kprobe *tk)
{
+ /* If other probes are on the event, just unregister kprobe */
+ if (trace_probe_has_sibling(&tk->tp))
+ goto unreg;
+
/* Enabled event can not be unregistered */
if (trace_probe_is_enabled(&tk->tp))
return -EBUSY;
@@ -445,12 +520,81 @@ static int unregister_trace_kprobe(struct trace_kprobe *tk)
if (unregister_kprobe_event(tk))
return -EBUSY;
+unreg:
__unregister_trace_kprobe(tk);
dyn_event_remove(&tk->devent);
+ trace_probe_unlink(&tk->tp);
return 0;
}
+static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig,
+ struct trace_kprobe *comp)
+{
+ struct trace_probe_event *tpe = orig->tp.event;
+ struct trace_probe *pos;
+ int i;
+
+ list_for_each_entry(pos, &tpe->probes, list) {
+ orig = container_of(pos, struct trace_kprobe, tp);
+ if (strcmp(trace_kprobe_symbol(orig),
+ trace_kprobe_symbol(comp)) ||
+ trace_kprobe_offset(orig) != trace_kprobe_offset(comp))
+ continue;
+
+ /*
+ * trace_probe_compare_arg_type() ensured that nr_args and
+ * each argument name and type are same. Let's compare comm.
+ */
+ for (i = 0; i < orig->tp.nr_args; i++) {
+ if (strcmp(orig->tp.args[i].comm,
+ comp->tp.args[i].comm))
+ continue;
+ }
+
+ return true;
+ }
+
+ return false;
+}
+
+static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to)
+{
+ int ret;
+
+ ret = trace_probe_compare_arg_type(&tk->tp, &to->tp);
+ if (ret) {
+ /* Note that argument starts index = 2 */
+ trace_probe_log_set_index(ret + 1);
+ trace_probe_log_err(0, DIFF_ARG_TYPE);
+ return -EEXIST;
+ }
+ if (trace_kprobe_has_same_kprobe(to, tk)) {
+ trace_probe_log_set_index(0);
+ trace_probe_log_err(0, SAME_PROBE);
+ return -EEXIST;
+ }
+
+ /* Append to existing event */
+ ret = trace_probe_append(&tk->tp, &to->tp);
+ if (ret)
+ return ret;
+
+ /* Register k*probe */
+ ret = __register_trace_kprobe(tk);
+ if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) {
+ pr_warn("This probe might be able to register after target module is loaded. Continue.\n");
+ ret = 0;
+ }
+
+ if (ret)
+ trace_probe_unlink(&tk->tp);
+ else
+ dyn_event_add(&tk->devent);
+
+ return ret;
+}
+
/* Register a trace_probe and probe_event */
static int register_trace_kprobe(struct trace_kprobe *tk)
{
@@ -459,14 +603,17 @@ static int register_trace_kprobe(struct trace_kprobe *tk)
mutex_lock(&event_mutex);
- /* Delete old (same name) event if exist */
old_tk = find_trace_kprobe(trace_probe_name(&tk->tp),
trace_probe_group_name(&tk->tp));
if (old_tk) {
- ret = unregister_trace_kprobe(old_tk);
- if (ret < 0)
- goto end;
- free_trace_kprobe(old_tk);
+ if (trace_kprobe_is_return(tk) != trace_kprobe_is_return(old_tk)) {
+ trace_probe_log_set_index(0);
+ trace_probe_log_err(0, DIFF_PROBE_TYPE);
+ ret = -EEXIST;
+ } else {
+ ret = append_trace_kprobe(tk, old_tk);
+ }
+ goto end;
}
/* Register new event */
@@ -700,7 +847,7 @@ static int trace_kprobe_create(int argc, const char *argv[])
trace_probe_log_err(0, BAD_INSN_BNDRY);
else if (ret == -ENOENT)
trace_probe_log_err(0, BAD_PROBE_ADDR);
- else if (ret != -ENOMEM)
+ else if (ret != -ENOMEM && ret != -EEXIST)
trace_probe_log_err(0, FAIL_REG_PROBE);
goto error;
}
@@ -965,6 +1112,9 @@ retry:
case FETCH_OP_COMM:
val = (unsigned long)current->comm;
break;
+ case FETCH_OP_DATA:
+ val = (unsigned long)code->data;
+ break;
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
case FETCH_OP_ARG:
val = regs_get_kernel_argument(regs, code->param);
@@ -1089,7 +1239,10 @@ print_kprobe_event(struct trace_iterator *iter, int flags,
struct trace_probe *tp;
field = (struct kprobe_trace_entry_head *)iter->ent;
- tp = container_of(event, struct trace_probe, call.event);
+ tp = trace_probe_primary_from_call(
+ container_of(event, struct trace_event_call, event));
+ if (WARN_ON_ONCE(!tp))
+ goto out;
trace_seq_printf(s, "%s: (", trace_probe_name(tp));
@@ -1116,7 +1269,10 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,
struct trace_probe *tp;
field = (struct kretprobe_trace_entry_head *)iter->ent;
- tp = container_of(event, struct trace_probe, call.event);
+ tp = trace_probe_primary_from_call(
+ container_of(event, struct trace_event_call, event));
+ if (WARN_ON_ONCE(!tp))
+ goto out;
trace_seq_printf(s, "%s: (", trace_probe_name(tp));
@@ -1145,23 +1301,31 @@ static int kprobe_event_define_fields(struct trace_event_call *event_call)
{
int ret;
struct kprobe_trace_entry_head field;
- struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data;
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(event_call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENOENT;
DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
- return traceprobe_define_arg_fields(event_call, sizeof(field), &tk->tp);
+ return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
}
static int kretprobe_event_define_fields(struct trace_event_call *event_call)
{
int ret;
struct kretprobe_trace_entry_head field;
- struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data;
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(event_call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENOENT;
DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
- return traceprobe_define_arg_fields(event_call, sizeof(field), &tk->tp);
+ return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
}
#ifdef CONFIG_PERF_EVENTS
@@ -1289,20 +1453,19 @@ int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type,
static int kprobe_register(struct trace_event_call *event,
enum trace_reg type, void *data)
{
- struct trace_kprobe *tk = (struct trace_kprobe *)event->data;
struct trace_event_file *file = data;
switch (type) {
case TRACE_REG_REGISTER:
- return enable_trace_kprobe(tk, file);
+ return enable_trace_kprobe(event, file);
case TRACE_REG_UNREGISTER:
- return disable_trace_kprobe(tk, file);
+ return disable_trace_kprobe(event, file);
#ifdef CONFIG_PERF_EVENTS
case TRACE_REG_PERF_REGISTER:
- return enable_trace_kprobe(tk, NULL);
+ return enable_trace_kprobe(event, NULL);
case TRACE_REG_PERF_UNREGISTER:
- return disable_trace_kprobe(tk, NULL);
+ return disable_trace_kprobe(event, NULL);
case TRACE_REG_PERF_OPEN:
case TRACE_REG_PERF_CLOSE:
case TRACE_REG_PERF_ADD:
@@ -1369,7 +1532,6 @@ static inline void init_trace_event_call(struct trace_kprobe *tk)
call->flags = TRACE_EVENT_FL_KPROBE;
call->class->reg = kprobe_register;
- call->data = tk;
}
static int register_kprobe_event(struct trace_kprobe *tk)
@@ -1432,7 +1594,9 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call)
{
struct trace_kprobe *tk;
- tk = container_of(event_call, struct trace_kprobe, tp.call);
+ tk = trace_kprobe_primary_from_call(event_call);
+ if (unlikely(!tk))
+ return;
if (trace_probe_is_enabled(&tk->tp)) {
WARN_ON(1);
@@ -1577,7 +1741,8 @@ static __init int kprobe_trace_self_tests_init(void)
pr_warn("error on getting probe file.\n");
warn++;
} else
- enable_trace_kprobe(tk, file);
+ enable_trace_kprobe(
+ trace_probe_event_call(&tk->tp), file);
}
}
@@ -1598,7 +1763,8 @@ static __init int kprobe_trace_self_tests_init(void)
pr_warn("error on getting probe file.\n");
warn++;
} else
- enable_trace_kprobe(tk, file);
+ enable_trace_kprobe(
+ trace_probe_event_call(&tk->tp), file);
}
}
@@ -1631,7 +1797,8 @@ static __init int kprobe_trace_self_tests_init(void)
pr_warn("error on getting probe file.\n");
warn++;
} else
- disable_trace_kprobe(tk, file);
+ disable_trace_kprobe(
+ trace_probe_event_call(&tk->tp), file);
}
tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
@@ -1649,7 +1816,8 @@ static __init int kprobe_trace_self_tests_init(void)
pr_warn("error on getting probe file.\n");
warn++;
} else
- disable_trace_kprobe(tk, file);
+ disable_trace_kprobe(
+ trace_probe_event_call(&tk->tp), file);
}
ret = trace_run_command("-:testprobe", create_or_delete_trace_kprobe);
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index cab4a5398f1d..d54ce252b05a 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -219,10 +219,10 @@ trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len,
{
int i;
const char *ret = trace_seq_buffer_ptr(p);
+ const char *fmt = concatenate ? "%*phN" : "%*ph";
- for (i = 0; i < buf_len; i++)
- trace_seq_printf(p, "%s%2.2x", concatenate || i == 0 ? "" : " ",
- buf[i]);
+ for (i = 0; i < buf_len; i += 16)
+ trace_seq_printf(p, fmt, min(buf_len - i, 16), &buf[i]);
trace_seq_putc(p, 0);
return ret;
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index fb6bfbc5bf86..baf58a3612c0 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -316,6 +316,29 @@ inval_var:
return -EINVAL;
}
+static int str_to_immediate(char *str, unsigned long *imm)
+{
+ if (isdigit(str[0]))
+ return kstrtoul(str, 0, imm);
+ else if (str[0] == '-')
+ return kstrtol(str, 0, (long *)imm);
+ else if (str[0] == '+')
+ return kstrtol(str + 1, 0, (long *)imm);
+ return -EINVAL;
+}
+
+static int __parse_imm_string(char *str, char **pbuf, int offs)
+{
+ size_t len = strlen(str);
+
+ if (str[len - 1] != '"') {
+ trace_probe_log_err(offs + len, IMMSTR_NO_CLOSE);
+ return -EINVAL;
+ }
+ *pbuf = kstrndup(str, len - 1, GFP_KERNEL);
+ return 0;
+}
+
/* Recursive argument parser */
static int
parse_probe_arg(char *arg, const struct fetch_type *type,
@@ -430,7 +453,8 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
ret = parse_probe_arg(arg, t2, &code, end, flags, offs);
if (ret)
break;
- if (code->op == FETCH_OP_COMM) {
+ if (code->op == FETCH_OP_COMM ||
+ code->op == FETCH_OP_DATA) {
trace_probe_log_err(offs, COMM_CANT_DEREF);
return -EINVAL;
}
@@ -444,6 +468,21 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
code->offset = offset;
}
break;
+ case '\\': /* Immediate value */
+ if (arg[1] == '"') { /* Immediate string */
+ ret = __parse_imm_string(arg + 2, &tmp, offs + 2);
+ if (ret)
+ break;
+ code->op = FETCH_OP_DATA;
+ code->data = tmp;
+ } else {
+ ret = str_to_immediate(arg + 1, &code->immediate);
+ if (ret)
+ trace_probe_log_err(offs + 1, BAD_IMM);
+ else
+ code->op = FETCH_OP_IMM;
+ }
+ break;
}
if (!ret && code->op == FETCH_OP_NOP) {
/* Parsed, but do not find fetch method */
@@ -542,8 +581,11 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
}
}
- /* Since $comm can not be dereferred, we can find $comm by strcmp */
- if (strcmp(arg, "$comm") == 0) {
+ /*
+ * Since $comm and immediate string can not be dereferred,
+ * we can find those by strcmp.
+ */
+ if (strcmp(arg, "$comm") == 0 || strncmp(arg, "\\\"", 2) == 0) {
/* The type of $comm must be "string", and not an array. */
if (parg->count || (t && strcmp(t, "string")))
return -EINVAL;
@@ -580,7 +622,8 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
if (!strcmp(parg->type->name, "string") ||
!strcmp(parg->type->name, "ustring")) {
if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF &&
- code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM) {
+ code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM &&
+ code->op != FETCH_OP_DATA) {
trace_probe_log_err(offset + (t ? (t - arg) : 0),
BAD_STRING);
ret = -EINVAL;
@@ -589,9 +632,10 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
if ((code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM) ||
parg->count) {
/*
- * IMM and COMM is pointing actual address, those must
- * be kept, and if parg->count != 0, this is an array
- * of string pointers instead of string address itself.
+ * IMM, DATA and COMM is pointing actual address, those
+ * must be kept, and if parg->count != 0, this is an
+ * array of string pointers instead of string address
+ * itself.
*/
code++;
if (code->op != FETCH_OP_NOP) {
@@ -665,7 +709,8 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
fail:
if (ret) {
for (code = tmp; code < tmp + FETCH_INSN_MAX; code++)
- if (code->op == FETCH_NOP_SYMBOL)
+ if (code->op == FETCH_NOP_SYMBOL ||
+ code->op == FETCH_OP_DATA)
kfree(code->data);
}
kfree(tmp);
@@ -736,7 +781,8 @@ void traceprobe_free_probe_arg(struct probe_arg *arg)
struct fetch_insn *code = arg->code;
while (code && code->op != FETCH_OP_END) {
- if (code->op == FETCH_NOP_SYMBOL)
+ if (code->op == FETCH_NOP_SYMBOL ||
+ code->op == FETCH_OP_DATA)
kfree(code->data);
code++;
}
@@ -886,44 +932,85 @@ int traceprobe_define_arg_fields(struct trace_event_call *event_call,
return 0;
}
+static void trace_probe_event_free(struct trace_probe_event *tpe)
+{
+ kfree(tpe->class.system);
+ kfree(tpe->call.name);
+ kfree(tpe->call.print_fmt);
+ kfree(tpe);
+}
+
+int trace_probe_append(struct trace_probe *tp, struct trace_probe *to)
+{
+ if (trace_probe_has_sibling(tp))
+ return -EBUSY;
+
+ list_del_init(&tp->list);
+ trace_probe_event_free(tp->event);
+
+ tp->event = to->event;
+ list_add_tail(&tp->list, trace_probe_probe_list(to));
+
+ return 0;
+}
+
+void trace_probe_unlink(struct trace_probe *tp)
+{
+ list_del_init(&tp->list);
+ if (list_empty(trace_probe_probe_list(tp)))
+ trace_probe_event_free(tp->event);
+ tp->event = NULL;
+}
void trace_probe_cleanup(struct trace_probe *tp)
{
- struct trace_event_call *call = trace_probe_event_call(tp);
int i;
for (i = 0; i < tp->nr_args; i++)
traceprobe_free_probe_arg(&tp->args[i]);
- if (call->class)
- kfree(call->class->system);
- kfree(call->name);
- kfree(call->print_fmt);
+ if (tp->event)
+ trace_probe_unlink(tp);
}
int trace_probe_init(struct trace_probe *tp, const char *event,
const char *group)
{
- struct trace_event_call *call = trace_probe_event_call(tp);
+ struct trace_event_call *call;
+ int ret = 0;
if (!event || !group)
return -EINVAL;
- call->class = &tp->class;
- call->name = kstrdup(event, GFP_KERNEL);
- if (!call->name)
+ tp->event = kzalloc(sizeof(struct trace_probe_event), GFP_KERNEL);
+ if (!tp->event)
return -ENOMEM;
- tp->class.system = kstrdup(group, GFP_KERNEL);
- if (!tp->class.system) {
- kfree(call->name);
- call->name = NULL;
- return -ENOMEM;
+ INIT_LIST_HEAD(&tp->event->files);
+ INIT_LIST_HEAD(&tp->event->class.fields);
+ INIT_LIST_HEAD(&tp->event->probes);
+ INIT_LIST_HEAD(&tp->list);
+ list_add(&tp->event->probes, &tp->list);
+
+ call = trace_probe_event_call(tp);
+ call->class = &tp->event->class;
+ call->name = kstrdup(event, GFP_KERNEL);
+ if (!call->name) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ tp->event->class.system = kstrdup(group, GFP_KERNEL);
+ if (!tp->event->class.system) {
+ ret = -ENOMEM;
+ goto error;
}
- INIT_LIST_HEAD(&tp->files);
- INIT_LIST_HEAD(&tp->class.fields);
return 0;
+
+error:
+ trace_probe_cleanup(tp);
+ return ret;
}
int trace_probe_register_event_call(struct trace_probe *tp)
@@ -952,7 +1039,7 @@ int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file)
link->file = file;
INIT_LIST_HEAD(&link->list);
- list_add_tail_rcu(&link->list, &tp->files);
+ list_add_tail_rcu(&link->list, &tp->event->files);
trace_probe_set_flag(tp, TP_FLAG_TRACE);
return 0;
}
@@ -983,8 +1070,45 @@ int trace_probe_remove_file(struct trace_probe *tp,
synchronize_rcu();
kfree(link);
- if (list_empty(&tp->files))
+ if (list_empty(&tp->event->files))
trace_probe_clear_flag(tp, TP_FLAG_TRACE);
return 0;
}
+
+/*
+ * Return the smallest index of different type argument (start from 1).
+ * If all argument types and name are same, return 0.
+ */
+int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b)
+{
+ int i;
+
+ for (i = 0; i < a->nr_args; i++) {
+ if ((b->nr_args <= i) ||
+ ((a->args[i].type != b->args[i].type) ||
+ (a->args[i].count != b->args[i].count) ||
+ strcmp(a->args[i].name, b->args[i].name)))
+ return i + 1;
+ }
+
+ return 0;
+}
+
+bool trace_probe_match_command_args(struct trace_probe *tp,
+ int argc, const char **argv)
+{
+ char buf[MAX_ARGSTR_LEN + 1];
+ int i;
+
+ if (tp->nr_args < argc)
+ return false;
+
+ for (i = 0; i < argc; i++) {
+ snprintf(buf, sizeof(buf), "%s=%s",
+ tp->args[i].name, tp->args[i].comm);
+ if (strcmp(buf, argv[i]))
+ return false;
+ }
+ return true;
+}
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index d1714820efe1..4ee703728aec 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -89,6 +89,7 @@ enum fetch_op {
FETCH_OP_COMM, /* Current comm */
FETCH_OP_ARG, /* Function argument : .param */
FETCH_OP_FOFFS, /* File offset: .immediate */
+ FETCH_OP_DATA, /* Allocated data: .data */
// Stage 2 (dereference) op
FETCH_OP_DEREF, /* Dereference: .offset */
FETCH_OP_UDEREF, /* User-space Dereference: .offset */
@@ -222,11 +223,18 @@ struct probe_arg {
const struct fetch_type *type; /* Type of this argument */
};
-struct trace_probe {
+/* Event call and class holder */
+struct trace_probe_event {
unsigned int flags; /* For TP_FLAG_* */
struct trace_event_class class;
struct trace_event_call call;
struct list_head files;
+ struct list_head probes;
+};
+
+struct trace_probe {
+ struct list_head list;
+ struct trace_probe_event *event;
ssize_t size; /* trace entry size */
unsigned int nr_args;
struct probe_arg args[];
@@ -240,19 +248,19 @@ struct event_file_link {
static inline bool trace_probe_test_flag(struct trace_probe *tp,
unsigned int flag)
{
- return !!(tp->flags & flag);
+ return !!(tp->event->flags & flag);
}
static inline void trace_probe_set_flag(struct trace_probe *tp,
unsigned int flag)
{
- tp->flags |= flag;
+ tp->event->flags |= flag;
}
static inline void trace_probe_clear_flag(struct trace_probe *tp,
unsigned int flag)
{
- tp->flags &= ~flag;
+ tp->event->flags &= ~flag;
}
static inline bool trace_probe_is_enabled(struct trace_probe *tp)
@@ -262,45 +270,76 @@ static inline bool trace_probe_is_enabled(struct trace_probe *tp)
static inline const char *trace_probe_name(struct trace_probe *tp)
{
- return trace_event_name(&tp->call);
+ return trace_event_name(&tp->event->call);
}
static inline const char *trace_probe_group_name(struct trace_probe *tp)
{
- return tp->call.class->system;
+ return tp->event->call.class->system;
}
static inline struct trace_event_call *
trace_probe_event_call(struct trace_probe *tp)
{
- return &tp->call;
+ return &tp->event->call;
+}
+
+static inline struct trace_probe_event *
+trace_probe_event_from_call(struct trace_event_call *event_call)
+{
+ return container_of(event_call, struct trace_probe_event, call);
+}
+
+static inline struct trace_probe *
+trace_probe_primary_from_call(struct trace_event_call *call)
+{
+ struct trace_probe_event *tpe = trace_probe_event_from_call(call);
+
+ return list_first_entry(&tpe->probes, struct trace_probe, list);
+}
+
+static inline struct list_head *trace_probe_probe_list(struct trace_probe *tp)
+{
+ return &tp->event->probes;
+}
+
+static inline bool trace_probe_has_sibling(struct trace_probe *tp)
+{
+ struct list_head *list = trace_probe_probe_list(tp);
+
+ return !list_empty(list) && !list_is_singular(list);
}
static inline int trace_probe_unregister_event_call(struct trace_probe *tp)
{
/* tp->event is unregistered in trace_remove_event_call() */
- return trace_remove_event_call(&tp->call);
+ return trace_remove_event_call(&tp->event->call);
}
static inline bool trace_probe_has_single_file(struct trace_probe *tp)
{
- return !!list_is_singular(&tp->files);
+ return !!list_is_singular(&tp->event->files);
}
int trace_probe_init(struct trace_probe *tp, const char *event,
const char *group);
void trace_probe_cleanup(struct trace_probe *tp);
+int trace_probe_append(struct trace_probe *tp, struct trace_probe *to);
+void trace_probe_unlink(struct trace_probe *tp);
int trace_probe_register_event_call(struct trace_probe *tp);
int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file);
int trace_probe_remove_file(struct trace_probe *tp,
struct trace_event_file *file);
struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp,
struct trace_event_file *file);
+int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b);
+bool trace_probe_match_command_args(struct trace_probe *tp,
+ int argc, const char **argv);
#define trace_probe_for_each_link(pos, tp) \
- list_for_each_entry(pos, &(tp)->files, list)
+ list_for_each_entry(pos, &(tp)->event->files, list)
#define trace_probe_for_each_link_rcu(pos, tp) \
- list_for_each_entry_rcu(pos, &(tp)->files, list)
+ list_for_each_entry_rcu(pos, &(tp)->event->files, list)
/* Check the name is good for event/group/fields */
static inline bool is_good_name(const char *name)
@@ -370,6 +409,8 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(BAD_VAR, "Invalid $-valiable specified"), \
C(BAD_REG_NAME, "Invalid register name"), \
C(BAD_MEM_ADDR, "Invalid memory address"), \
+ C(BAD_IMM, "Invalid immediate value"), \
+ C(IMMSTR_NO_CLOSE, "String is not closed with '\"'"), \
C(FILE_ON_KPROBE, "File offset is not available with kprobe"), \
C(BAD_FILE_OFFS, "Invalid file offset value"), \
C(SYM_ON_UPROBE, "Symbol is not available with uprobe"), \
@@ -393,7 +434,10 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(ARG_TOO_LONG, "Argument expression is too long"), \
C(NO_ARG_BODY, "No argument expression"), \
C(BAD_INSN_BNDRY, "Probe point is not an instruction boundary"),\
- C(FAIL_REG_PROBE, "Failed to register probe event"),
+ C(FAIL_REG_PROBE, "Failed to register probe event"),\
+ C(DIFF_PROBE_TYPE, "Probe type is different from existing probe"),\
+ C(DIFF_ARG_TYPE, "Argument type or name is different from existing probe"),\
+ C(SAME_PROBE, "There is already the exact same probe event"),
#undef C
#define C(a, b) TP_ERR_##a
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 5d16f73898db..ec9a34a97129 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -53,6 +53,104 @@ static void print_max_stack(void)
}
}
+/*
+ * The stack tracer looks for a maximum stack at each call from a function. It
+ * registers a callback from ftrace, and in that callback it examines the stack
+ * size. It determines the stack size from the variable passed in, which is the
+ * address of a local variable in the stack_trace_call() callback function.
+ * The stack size is calculated by the address of the local variable to the top
+ * of the current stack. If that size is smaller than the currently saved max
+ * stack size, nothing more is done.
+ *
+ * If the size of the stack is greater than the maximum recorded size, then the
+ * following algorithm takes place.
+ *
+ * For architectures (like x86) that store the function's return address before
+ * saving the function's local variables, the stack will look something like
+ * this:
+ *
+ * [ top of stack ]
+ * 0: sys call entry frame
+ * 10: return addr to entry code
+ * 11: start of sys_foo frame
+ * 20: return addr to sys_foo
+ * 21: start of kernel_func_bar frame
+ * 30: return addr to kernel_func_bar
+ * 31: [ do trace stack here ]
+ *
+ * The save_stack_trace() is called returning all the functions it finds in the
+ * current stack. Which would be (from the bottom of the stack to the top):
+ *
+ * return addr to kernel_func_bar
+ * return addr to sys_foo
+ * return addr to entry code
+ *
+ * Now to figure out how much each of these functions' local variable size is,
+ * a search of the stack is made to find these values. When a match is made, it
+ * is added to the stack_dump_trace[] array. The offset into the stack is saved
+ * in the stack_trace_index[] array. The above example would show:
+ *
+ * stack_dump_trace[] | stack_trace_index[]
+ * ------------------ + -------------------
+ * return addr to kernel_func_bar | 30
+ * return addr to sys_foo | 20
+ * return addr to entry | 10
+ *
+ * The print_max_stack() function above, uses these values to print the size of
+ * each function's portion of the stack.
+ *
+ * for (i = 0; i < nr_entries; i++) {
+ * size = i == nr_entries - 1 ? stack_trace_index[i] :
+ * stack_trace_index[i] - stack_trace_index[i+1]
+ * print "%d %d %d %s\n", i, stack_trace_index[i], size, stack_dump_trace[i]);
+ * }
+ *
+ * The above shows
+ *
+ * depth size location
+ * ----- ---- --------
+ * 0 30 10 kernel_func_bar
+ * 1 20 10 sys_foo
+ * 2 10 10 entry code
+ *
+ * Now for architectures that might save the return address after the functions
+ * local variables (saving the link register before calling nested functions),
+ * this will cause the stack to look a little different:
+ *
+ * [ top of stack ]
+ * 0: sys call entry frame
+ * 10: start of sys_foo_frame
+ * 19: return addr to entry code << lr saved before calling kernel_func_bar
+ * 20: start of kernel_func_bar frame
+ * 29: return addr to sys_foo_frame << lr saved before calling next function
+ * 30: [ do trace stack here ]
+ *
+ * Although the functions returned by save_stack_trace() may be the same, the
+ * placement in the stack will be different. Using the same algorithm as above
+ * would yield:
+ *
+ * stack_dump_trace[] | stack_trace_index[]
+ * ------------------ + -------------------
+ * return addr to kernel_func_bar | 30
+ * return addr to sys_foo | 29
+ * return addr to entry | 19
+ *
+ * Where the mapping is off by one:
+ *
+ * kernel_func_bar stack frame size is 29 - 19 not 30 - 29!
+ *
+ * To fix this, if the architecture sets ARCH_RET_ADDR_AFTER_LOCAL_VARS the
+ * values in stack_trace_index[] are shifted by one to and the number of
+ * stack trace entries is decremented by one.
+ *
+ * stack_dump_trace[] | stack_trace_index[]
+ * ------------------ + -------------------
+ * return addr to kernel_func_bar | 29
+ * return addr to sys_foo | 19
+ *
+ * Although the entry function is not displayed, the first function (sys_foo)
+ * will still include the stack size of it.
+ */
static void check_stack(unsigned long ip, unsigned long *stack)
{
unsigned long this_size, flags; unsigned long *p, *top, *start;
@@ -158,6 +256,20 @@ static void check_stack(unsigned long ip, unsigned long *stack)
i++;
}
+#ifdef ARCH_FTRACE_SHIFT_STACK_TRACER
+ /*
+ * Some archs will store the link register before calling
+ * nested functions. This means the saved return address
+ * comes after the local storage, and we need to shift
+ * for that.
+ */
+ if (x > 1) {
+ memmove(&stack_trace_index[0], &stack_trace_index[1],
+ sizeof(stack_trace_index[0]) * (x - 1));
+ x--;
+ }
+#endif
+
stack_trace_nr_entries = x;
if (task_stack_end_corrupted(current)) {
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 1ceedb9146b1..34dd6d0016a3 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -44,7 +44,7 @@ static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev);
static int trace_uprobe_release(struct dyn_event *ev);
static bool trace_uprobe_is_busy(struct dyn_event *ev);
static bool trace_uprobe_match(const char *system, const char *event,
- struct dyn_event *ev);
+ int argc, const char **argv, struct dyn_event *ev);
static struct dyn_event_operations trace_uprobe_ops = {
.create = trace_uprobe_create,
@@ -248,6 +248,9 @@ process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
case FETCH_OP_COMM:
val = FETCH_TOKEN_COMM;
break;
+ case FETCH_OP_DATA:
+ val = (unsigned long)code->data;
+ break;
case FETCH_OP_FOFFS:
val = translate_user_vaddr(code->immediate);
break;
@@ -284,13 +287,54 @@ static bool trace_uprobe_is_busy(struct dyn_event *ev)
return trace_probe_is_enabled(&tu->tp);
}
+static bool trace_uprobe_match_command_head(struct trace_uprobe *tu,
+ int argc, const char **argv)
+{
+ char buf[MAX_ARGSTR_LEN + 1];
+ int len;
+
+ if (!argc)
+ return true;
+
+ len = strlen(tu->filename);
+ if (strncmp(tu->filename, argv[0], len) || argv[0][len] != ':')
+ return false;
+
+ if (tu->ref_ctr_offset == 0)
+ snprintf(buf, sizeof(buf), "0x%0*lx",
+ (int)(sizeof(void *) * 2), tu->offset);
+ else
+ snprintf(buf, sizeof(buf), "0x%0*lx(0x%lx)",
+ (int)(sizeof(void *) * 2), tu->offset,
+ tu->ref_ctr_offset);
+ if (strcmp(buf, &argv[0][len + 1]))
+ return false;
+
+ argc--; argv++;
+
+ return trace_probe_match_command_args(&tu->tp, argc, argv);
+}
+
static bool trace_uprobe_match(const char *system, const char *event,
- struct dyn_event *ev)
+ int argc, const char **argv, struct dyn_event *ev)
{
struct trace_uprobe *tu = to_trace_uprobe(ev);
return strcmp(trace_probe_name(&tu->tp), event) == 0 &&
- (!system || strcmp(trace_probe_group_name(&tu->tp), system) == 0);
+ (!system || strcmp(trace_probe_group_name(&tu->tp), system) == 0) &&
+ trace_uprobe_match_command_head(tu, argc, argv);
+}
+
+static nokprobe_inline struct trace_uprobe *
+trace_uprobe_primary_from_call(struct trace_event_call *call)
+{
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return NULL;
+
+ return container_of(tp, struct trace_uprobe, tp);
}
/*
@@ -352,15 +396,75 @@ static int unregister_trace_uprobe(struct trace_uprobe *tu)
{
int ret;
+ if (trace_probe_has_sibling(&tu->tp))
+ goto unreg;
+
ret = unregister_uprobe_event(tu);
if (ret)
return ret;
+unreg:
dyn_event_remove(&tu->devent);
+ trace_probe_unlink(&tu->tp);
free_trace_uprobe(tu);
return 0;
}
+static bool trace_uprobe_has_same_uprobe(struct trace_uprobe *orig,
+ struct trace_uprobe *comp)
+{
+ struct trace_probe_event *tpe = orig->tp.event;
+ struct trace_probe *pos;
+ struct inode *comp_inode = d_real_inode(comp->path.dentry);
+ int i;
+
+ list_for_each_entry(pos, &tpe->probes, list) {
+ orig = container_of(pos, struct trace_uprobe, tp);
+ if (comp_inode != d_real_inode(orig->path.dentry) ||
+ comp->offset != orig->offset)
+ continue;
+
+ /*
+ * trace_probe_compare_arg_type() ensured that nr_args and
+ * each argument name and type are same. Let's compare comm.
+ */
+ for (i = 0; i < orig->tp.nr_args; i++) {
+ if (strcmp(orig->tp.args[i].comm,
+ comp->tp.args[i].comm))
+ continue;
+ }
+
+ return true;
+ }
+
+ return false;
+}
+
+static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to)
+{
+ int ret;
+
+ ret = trace_probe_compare_arg_type(&tu->tp, &to->tp);
+ if (ret) {
+ /* Note that argument starts index = 2 */
+ trace_probe_log_set_index(ret + 1);
+ trace_probe_log_err(0, DIFF_ARG_TYPE);
+ return -EEXIST;
+ }
+ if (trace_uprobe_has_same_uprobe(to, tu)) {
+ trace_probe_log_set_index(0);
+ trace_probe_log_err(0, SAME_PROBE);
+ return -EEXIST;
+ }
+
+ /* Append to existing event */
+ ret = trace_probe_append(&tu->tp, &to->tp);
+ if (!ret)
+ dyn_event_add(&tu->devent);
+
+ return ret;
+}
+
/*
* Uprobe with multiple reference counter is not allowed. i.e.
* If inode and offset matches, reference counter offset *must*
@@ -370,25 +474,21 @@ static int unregister_trace_uprobe(struct trace_uprobe *tu)
* as the new one does not conflict with any other existing
* ones.
*/
-static struct trace_uprobe *find_old_trace_uprobe(struct trace_uprobe *new)
+static int validate_ref_ctr_offset(struct trace_uprobe *new)
{
struct dyn_event *pos;
- struct trace_uprobe *tmp, *old = NULL;
+ struct trace_uprobe *tmp;
struct inode *new_inode = d_real_inode(new->path.dentry);
- old = find_probe_event(trace_probe_name(&new->tp),
- trace_probe_group_name(&new->tp));
-
for_each_trace_uprobe(tmp, pos) {
- if ((old ? old != tmp : true) &&
- new_inode == d_real_inode(tmp->path.dentry) &&
+ if (new_inode == d_real_inode(tmp->path.dentry) &&
new->offset == tmp->offset &&
new->ref_ctr_offset != tmp->ref_ctr_offset) {
pr_warn("Reference counter offset mismatch.");
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
}
}
- return old;
+ return 0;
}
/* Register a trace_uprobe and probe_event */
@@ -399,18 +499,22 @@ static int register_trace_uprobe(struct trace_uprobe *tu)
mutex_lock(&event_mutex);
- /* register as an event */
- old_tu = find_old_trace_uprobe(tu);
- if (IS_ERR(old_tu)) {
- ret = PTR_ERR(old_tu);
+ ret = validate_ref_ctr_offset(tu);
+ if (ret)
goto end;
- }
+ /* register as an event */
+ old_tu = find_probe_event(trace_probe_name(&tu->tp),
+ trace_probe_group_name(&tu->tp));
if (old_tu) {
- /* delete old event */
- ret = unregister_trace_uprobe(old_tu);
- if (ret)
- goto end;
+ if (is_ret_probe(tu) != is_ret_probe(old_tu)) {
+ trace_probe_log_set_index(0);
+ trace_probe_log_err(0, DIFF_PROBE_TYPE);
+ ret = -EEXIST;
+ } else {
+ ret = append_trace_uprobe(tu, old_tu);
+ }
+ goto end;
}
ret = register_uprobe_event(tu);
@@ -897,7 +1001,10 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e
u8 *data;
entry = (struct uprobe_trace_entry_head *)iter->ent;
- tu = container_of(event, struct trace_uprobe, tp.call.event);
+ tu = trace_uprobe_primary_from_call(
+ container_of(event, struct trace_event_call, event));
+ if (unlikely(!tu))
+ goto out;
if (is_ret_probe(tu)) {
trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)",
@@ -924,27 +1031,71 @@ typedef bool (*filter_func_t)(struct uprobe_consumer *self,
enum uprobe_filter_ctx ctx,
struct mm_struct *mm);
-static int
-probe_event_enable(struct trace_uprobe *tu, struct trace_event_file *file,
- filter_func_t filter)
+static int trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter)
{
- bool enabled = trace_probe_is_enabled(&tu->tp);
int ret;
+ tu->consumer.filter = filter;
+ tu->inode = d_real_inode(tu->path.dentry);
+
+ if (tu->ref_ctr_offset)
+ ret = uprobe_register_refctr(tu->inode, tu->offset,
+ tu->ref_ctr_offset, &tu->consumer);
+ else
+ ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
+
+ if (ret)
+ tu->inode = NULL;
+
+ return ret;
+}
+
+static void __probe_event_disable(struct trace_probe *tp)
+{
+ struct trace_probe *pos;
+ struct trace_uprobe *tu;
+
+ list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+ tu = container_of(pos, struct trace_uprobe, tp);
+ if (!tu->inode)
+ continue;
+
+ WARN_ON(!uprobe_filter_is_empty(&tu->filter));
+
+ uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
+ tu->inode = NULL;
+ }
+}
+
+static int probe_event_enable(struct trace_event_call *call,
+ struct trace_event_file *file, filter_func_t filter)
+{
+ struct trace_probe *pos, *tp;
+ struct trace_uprobe *tu;
+ bool enabled;
+ int ret;
+
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENODEV;
+ enabled = trace_probe_is_enabled(tp);
+
+ /* This may also change "enabled" state */
if (file) {
- if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE))
+ if (trace_probe_test_flag(tp, TP_FLAG_PROFILE))
return -EINTR;
- ret = trace_probe_add_file(&tu->tp, file);
+ ret = trace_probe_add_file(tp, file);
if (ret < 0)
return ret;
} else {
- if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
+ if (trace_probe_test_flag(tp, TP_FLAG_TRACE))
return -EINTR;
- trace_probe_set_flag(&tu->tp, TP_FLAG_PROFILE);
+ trace_probe_set_flag(tp, TP_FLAG_PROFILE);
}
+ tu = container_of(tp, struct trace_uprobe, tp);
WARN_ON(!uprobe_filter_is_empty(&tu->filter));
if (enabled)
@@ -954,18 +1105,15 @@ probe_event_enable(struct trace_uprobe *tu, struct trace_event_file *file,
if (ret)
goto err_flags;
- tu->consumer.filter = filter;
- tu->inode = d_real_inode(tu->path.dentry);
- if (tu->ref_ctr_offset) {
- ret = uprobe_register_refctr(tu->inode, tu->offset,
- tu->ref_ctr_offset, &tu->consumer);
- } else {
- ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
+ list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+ tu = container_of(pos, struct trace_uprobe, tp);
+ ret = trace_uprobe_enable(tu, filter);
+ if (ret) {
+ __probe_event_disable(tp);
+ goto err_buffer;
+ }
}
- if (ret)
- goto err_buffer;
-
return 0;
err_buffer:
@@ -973,33 +1121,35 @@ probe_event_enable(struct trace_uprobe *tu, struct trace_event_file *file,
err_flags:
if (file)
- trace_probe_remove_file(&tu->tp, file);
+ trace_probe_remove_file(tp, file);
else
- trace_probe_clear_flag(&tu->tp, TP_FLAG_PROFILE);
+ trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
return ret;
}
-static void
-probe_event_disable(struct trace_uprobe *tu, struct trace_event_file *file)
+static void probe_event_disable(struct trace_event_call *call,
+ struct trace_event_file *file)
{
- if (!trace_probe_is_enabled(&tu->tp))
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return;
+
+ if (!trace_probe_is_enabled(tp))
return;
if (file) {
- if (trace_probe_remove_file(&tu->tp, file) < 0)
+ if (trace_probe_remove_file(tp, file) < 0)
return;
- if (trace_probe_is_enabled(&tu->tp))
+ if (trace_probe_is_enabled(tp))
return;
} else
- trace_probe_clear_flag(&tu->tp, TP_FLAG_PROFILE);
-
- WARN_ON(!uprobe_filter_is_empty(&tu->filter));
-
- uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
- tu->inode = NULL;
+ trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
+ __probe_event_disable(tp);
uprobe_buffer_disable();
}
@@ -1007,7 +1157,11 @@ static int uprobe_event_define_fields(struct trace_event_call *event_call)
{
int ret, size;
struct uprobe_trace_entry_head field;
- struct trace_uprobe *tu = event_call->data;
+ struct trace_uprobe *tu;
+
+ tu = trace_uprobe_primary_from_call(event_call);
+ if (unlikely(!tu))
+ return -ENODEV;
if (is_ret_probe(tu)) {
DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_FUNC, 0);
@@ -1100,6 +1254,27 @@ static int uprobe_perf_open(struct trace_uprobe *tu, struct perf_event *event)
return err;
}
+static int uprobe_perf_multi_call(struct trace_event_call *call,
+ struct perf_event *event,
+ int (*op)(struct trace_uprobe *tu, struct perf_event *event))
+{
+ struct trace_probe *pos, *tp;
+ struct trace_uprobe *tu;
+ int ret = 0;
+
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENODEV;
+
+ list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+ tu = container_of(pos, struct trace_uprobe, tp);
+ ret = op(tu, event);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
static bool uprobe_perf_filter(struct uprobe_consumer *uc,
enum uprobe_filter_ctx ctx, struct mm_struct *mm)
{
@@ -1213,30 +1388,29 @@ static int
trace_uprobe_register(struct trace_event_call *event, enum trace_reg type,
void *data)
{
- struct trace_uprobe *tu = event->data;
struct trace_event_file *file = data;
switch (type) {
case TRACE_REG_REGISTER:
- return probe_event_enable(tu, file, NULL);
+ return probe_event_enable(event, file, NULL);
case TRACE_REG_UNREGISTER:
- probe_event_disable(tu, file);
+ probe_event_disable(event, file);
return 0;
#ifdef CONFIG_PERF_EVENTS
case TRACE_REG_PERF_REGISTER:
- return probe_event_enable(tu, NULL, uprobe_perf_filter);
+ return probe_event_enable(event, NULL, uprobe_perf_filter);
case TRACE_REG_PERF_UNREGISTER:
- probe_event_disable(tu, NULL);
+ probe_event_disable(event, NULL);
return 0;
case TRACE_REG_PERF_OPEN:
- return uprobe_perf_open(tu, data);
+ return uprobe_perf_multi_call(event, data, uprobe_perf_open);
case TRACE_REG_PERF_CLOSE:
- return uprobe_perf_close(tu, data);
+ return uprobe_perf_multi_call(event, data, uprobe_perf_close);
#endif
default:
@@ -1330,7 +1504,6 @@ static inline void init_trace_event_call(struct trace_uprobe *tu)
call->flags = TRACE_EVENT_FL_UPROBE | TRACE_EVENT_FL_CAP_ANY;
call->class->reg = trace_uprobe_register;
- call->data = tu;
}
static int register_uprobe_event(struct trace_uprobe *tu)
@@ -1399,7 +1572,7 @@ void destroy_local_trace_uprobe(struct trace_event_call *event_call)
{
struct trace_uprobe *tu;
- tu = container_of(event_call, struct trace_uprobe, tp.call);
+ tu = trace_uprobe_primary_from_call(event_call);
free_trace_uprobe(tu);
}