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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c585
1 files changed, 202 insertions, 383 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index be62f0ea1814..0e6d517e74e0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -26,6 +26,7 @@
#include <linux/hardirq.h>
#include <linux/linkage.h>
#include <linux/uaccess.h>
+#include <linux/cleanup.h>
#include <linux/vmalloc.h>
#include <linux/ftrace.h>
#include <linux/module.h>
@@ -535,19 +536,16 @@ LIST_HEAD(ftrace_trace_arrays);
int trace_array_get(struct trace_array *this_tr)
{
struct trace_array *tr;
- int ret = -ENODEV;
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
list_for_each_entry(tr, &ftrace_trace_arrays, list) {
if (tr == this_tr) {
tr->ref++;
- ret = 0;
- break;
+ return 0;
}
}
- mutex_unlock(&trace_types_lock);
- return ret;
+ return -ENODEV;
}
static void __trace_array_put(struct trace_array *this_tr)
@@ -1443,22 +1441,20 @@ EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data,
cond_update_fn_t update)
{
- struct cond_snapshot *cond_snapshot;
- int ret = 0;
+ struct cond_snapshot *cond_snapshot __free(kfree) =
+ kzalloc(sizeof(*cond_snapshot), GFP_KERNEL);
+ int ret;
- cond_snapshot = kzalloc(sizeof(*cond_snapshot), GFP_KERNEL);
if (!cond_snapshot)
return -ENOMEM;
cond_snapshot->cond_data = cond_data;
cond_snapshot->update = update;
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
- if (tr->current_trace->use_max_tr) {
- ret = -EBUSY;
- goto fail_unlock;
- }
+ if (tr->current_trace->use_max_tr)
+ return -EBUSY;
/*
* The cond_snapshot can only change to NULL without the
@@ -1468,29 +1464,20 @@ int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data,
* do safely with only holding the trace_types_lock and not
* having to take the max_lock.
*/
- if (tr->cond_snapshot) {
- ret = -EBUSY;
- goto fail_unlock;
- }
+ if (tr->cond_snapshot)
+ return -EBUSY;
ret = tracing_arm_snapshot_locked(tr);
if (ret)
- goto fail_unlock;
+ return ret;
local_irq_disable();
arch_spin_lock(&tr->max_lock);
- tr->cond_snapshot = cond_snapshot;
+ tr->cond_snapshot = no_free_ptr(cond_snapshot);
arch_spin_unlock(&tr->max_lock);
local_irq_enable();
- mutex_unlock(&trace_types_lock);
-
- return ret;
-
- fail_unlock:
- mutex_unlock(&trace_types_lock);
- kfree(cond_snapshot);
- return ret;
+ return 0;
}
EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable);
@@ -2203,10 +2190,10 @@ static __init int init_trace_selftests(void)
selftests_can_run = true;
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
if (list_empty(&postponed_selftests))
- goto out;
+ return 0;
pr_info("Running postponed tracer tests:\n");
@@ -2235,9 +2222,6 @@ static __init int init_trace_selftests(void)
}
tracing_selftest_running = false;
- out:
- mutex_unlock(&trace_types_lock);
-
return 0;
}
core_initcall(init_trace_selftests);
@@ -2807,7 +2791,7 @@ int tracepoint_printk_sysctl(const struct ctl_table *table, int write,
int save_tracepoint_printk;
int ret;
- mutex_lock(&tracepoint_printk_mutex);
+ guard(mutex)(&tracepoint_printk_mutex);
save_tracepoint_printk = tracepoint_printk;
ret = proc_dointvec(table, write, buffer, lenp, ppos);
@@ -2820,16 +2804,13 @@ int tracepoint_printk_sysctl(const struct ctl_table *table, int write,
tracepoint_printk = 0;
if (save_tracepoint_printk == tracepoint_printk)
- goto out;
+ return ret;
if (tracepoint_printk)
static_key_enable(&tracepoint_printk_key.key);
else
static_key_disable(&tracepoint_printk_key.key);
- out:
- mutex_unlock(&tracepoint_printk_mutex);
-
return ret;
}
@@ -3611,17 +3592,12 @@ char *trace_iter_expand_format(struct trace_iterator *iter)
}
/* Returns true if the string is safe to dereference from an event */
-static bool trace_safe_str(struct trace_iterator *iter, const char *str,
- bool star, int len)
+static bool trace_safe_str(struct trace_iterator *iter, const char *str)
{
unsigned long addr = (unsigned long)str;
struct trace_event *trace_event;
struct trace_event_call *event;
- /* Ignore strings with no length */
- if (star && !len)
- return true;
-
/* OK if part of the event data */
if ((addr >= (unsigned long)iter->ent) &&
(addr < (unsigned long)iter->ent + iter->ent_size))
@@ -3661,181 +3637,69 @@ static bool trace_safe_str(struct trace_iterator *iter, const char *str,
return false;
}
-static DEFINE_STATIC_KEY_FALSE(trace_no_verify);
-
-static int test_can_verify_check(const char *fmt, ...)
-{
- char buf[16];
- va_list ap;
- int ret;
-
- /*
- * The verifier is dependent on vsnprintf() modifies the va_list
- * passed to it, where it is sent as a reference. Some architectures
- * (like x86_32) passes it by value, which means that vsnprintf()
- * does not modify the va_list passed to it, and the verifier
- * would then need to be able to understand all the values that
- * vsnprintf can use. If it is passed by value, then the verifier
- * is disabled.
- */
- va_start(ap, fmt);
- vsnprintf(buf, 16, "%d", ap);
- ret = va_arg(ap, int);
- va_end(ap);
-
- return ret;
-}
-
-static void test_can_verify(void)
-{
- if (!test_can_verify_check("%d %d", 0, 1)) {
- pr_info("trace event string verifier disabled\n");
- static_branch_inc(&trace_no_verify);
- }
-}
-
/**
- * trace_check_vprintf - Check dereferenced strings while writing to the seq buffer
+ * ignore_event - Check dereferenced fields while writing to the seq buffer
* @iter: The iterator that holds the seq buffer and the event being printed
- * @fmt: The format used to print the event
- * @ap: The va_list holding the data to print from @fmt.
*
- * This writes the data into the @iter->seq buffer using the data from
- * @fmt and @ap. If the format has a %s, then the source of the string
- * is examined to make sure it is safe to print, otherwise it will
- * warn and print "[UNSAFE MEMORY]" in place of the dereferenced string
- * pointer.
+ * At boot up, test_event_printk() will flag any event that dereferences
+ * a string with "%s" that does exist in the ring buffer. It may still
+ * be valid, as the string may point to a static string in the kernel
+ * rodata that never gets freed. But if the string pointer is pointing
+ * to something that was allocated, there's a chance that it can be freed
+ * by the time the user reads the trace. This would cause a bad memory
+ * access by the kernel and possibly crash the system.
+ *
+ * This function will check if the event has any fields flagged as needing
+ * to be checked at runtime and perform those checks.
+ *
+ * If it is found that a field is unsafe, it will write into the @iter->seq
+ * a message stating what was found to be unsafe.
+ *
+ * @return: true if the event is unsafe and should be ignored,
+ * false otherwise.
*/
-void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
- va_list ap)
+bool ignore_event(struct trace_iterator *iter)
{
- long text_delta = 0;
- long data_delta = 0;
- const char *p = fmt;
- const char *str;
- bool good;
- int i, j;
+ struct ftrace_event_field *field;
+ struct trace_event *trace_event;
+ struct trace_event_call *event;
+ struct list_head *head;
+ struct trace_seq *seq;
+ const void *ptr;
- if (WARN_ON_ONCE(!fmt))
- return;
+ trace_event = ftrace_find_event(iter->ent->type);
- if (static_branch_unlikely(&trace_no_verify))
- goto print;
+ seq = &iter->seq;
- /*
- * When the kernel is booted with the tp_printk command line
- * parameter, trace events go directly through to printk().
- * It also is checked by this function, but it does not
- * have an associated trace_array (tr) for it.
- */
- if (iter->tr) {
- text_delta = iter->tr->text_delta;
- data_delta = iter->tr->data_delta;
+ if (!trace_event) {
+ trace_seq_printf(seq, "EVENT ID %d NOT FOUND?\n", iter->ent->type);
+ return true;
}
- /* Don't bother checking when doing a ftrace_dump() */
- if (iter->fmt == static_fmt_buf)
- goto print;
-
- while (*p) {
- bool star = false;
- int len = 0;
-
- j = 0;
-
- /*
- * We only care about %s and variants
- * as well as %p[sS] if delta is non-zero
- */
- for (i = 0; p[i]; i++) {
- if (i + 1 >= iter->fmt_size) {
- /*
- * If we can't expand the copy buffer,
- * just print it.
- */
- if (!trace_iter_expand_format(iter))
- goto print;
- }
-
- if (p[i] == '\\' && p[i+1]) {
- i++;
- continue;
- }
- if (p[i] == '%') {
- /* Need to test cases like %08.*s */
- for (j = 1; p[i+j]; j++) {
- if (isdigit(p[i+j]) ||
- p[i+j] == '.')
- continue;
- if (p[i+j] == '*') {
- star = true;
- continue;
- }
- break;
- }
- if (p[i+j] == 's')
- break;
-
- if (text_delta && p[i+1] == 'p' &&
- ((p[i+2] == 's' || p[i+2] == 'S')))
- break;
-
- star = false;
- }
- j = 0;
- }
- /* If no %s found then just print normally */
- if (!p[i])
- break;
-
- /* Copy up to the %s, and print that */
- strncpy(iter->fmt, p, i);
- iter->fmt[i] = '\0';
- trace_seq_vprintf(&iter->seq, iter->fmt, ap);
+ event = container_of(trace_event, struct trace_event_call, event);
+ if (!(event->flags & TRACE_EVENT_FL_TEST_STR))
+ return false;
- /* Add delta to %pS pointers */
- if (p[i+1] == 'p') {
- unsigned long addr;
- char fmt[4];
+ head = trace_get_fields(event);
+ if (!head) {
+ trace_seq_printf(seq, "FIELDS FOR EVENT '%s' NOT FOUND?\n",
+ trace_event_name(event));
+ return true;
+ }
- fmt[0] = '%';
- fmt[1] = 'p';
- fmt[2] = p[i+2]; /* Either %ps or %pS */
- fmt[3] = '\0';
+ /* Offsets are from the iter->ent that points to the raw event */
+ ptr = iter->ent;
- addr = va_arg(ap, unsigned long);
- addr += text_delta;
- trace_seq_printf(&iter->seq, fmt, (void *)addr);
+ list_for_each_entry(field, head, link) {
+ const char *str;
+ bool good;
- p += i + 3;
+ if (!field->needs_test)
continue;
- }
- /*
- * If iter->seq is full, the above call no longer guarantees
- * that ap is in sync with fmt processing, and further calls
- * to va_arg() can return wrong positional arguments.
- *
- * Ensure that ap is no longer used in this case.
- */
- if (iter->seq.full) {
- p = "";
- break;
- }
-
- if (star)
- len = va_arg(ap, int);
-
- /* The ap now points to the string data of the %s */
- str = va_arg(ap, const char *);
+ str = *(const char **)(ptr + field->offset);
- good = trace_safe_str(iter, str, star, len);
-
- /* Could be from the last boot */
- if (data_delta && !good) {
- str += data_delta;
- good = trace_safe_str(iter, str, star, len);
- }
+ good = trace_safe_str(iter, str);
/*
* If you hit this warning, it is likely that the
@@ -3846,44 +3710,14 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
* instead. See samples/trace_events/trace-events-sample.h
* for reference.
*/
- if (WARN_ONCE(!good, "fmt: '%s' current_buffer: '%s'",
- fmt, seq_buf_str(&iter->seq.seq))) {
- int ret;
-
- /* Try to safely read the string */
- if (star) {
- if (len + 1 > iter->fmt_size)
- len = iter->fmt_size - 1;
- if (len < 0)
- len = 0;
- ret = copy_from_kernel_nofault(iter->fmt, str, len);
- iter->fmt[len] = 0;
- star = false;
- } else {
- ret = strncpy_from_kernel_nofault(iter->fmt, str,
- iter->fmt_size);
- }
- if (ret < 0)
- trace_seq_printf(&iter->seq, "(0x%px)", str);
- else
- trace_seq_printf(&iter->seq, "(0x%px:%s)",
- str, iter->fmt);
- str = "[UNSAFE-MEMORY]";
- strcpy(iter->fmt, "%s");
- } else {
- strncpy(iter->fmt, p + i, j + 1);
- iter->fmt[j+1] = '\0';
+ if (WARN_ONCE(!good, "event '%s' has unsafe pointer field '%s'",
+ trace_event_name(event), field->name)) {
+ trace_seq_printf(seq, "EVENT %s: HAS UNSAFE POINTER FIELD '%s'\n",
+ trace_event_name(event), field->name);
+ return true;
}
- if (star)
- trace_seq_printf(&iter->seq, iter->fmt, len, str);
- else
- trace_seq_printf(&iter->seq, iter->fmt, str);
-
- p += i + j + 1;
}
- print:
- if (*p)
- trace_seq_vprintf(&iter->seq, p, ap);
+ return false;
}
const char *trace_event_format(struct trace_iterator *iter, const char *fmt)
@@ -4269,6 +4103,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
preempt_model_none() ? "server" :
preempt_model_voluntary() ? "desktop" :
preempt_model_full() ? "preempt" :
+ preempt_model_lazy() ? "lazy" :
preempt_model_rt() ? "preempt_rt" :
"unknown",
/* These are reserved for later use */
@@ -4353,6 +4188,15 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
if (event) {
if (tr->trace_flags & TRACE_ITER_FIELDS)
return print_event_fields(iter, event);
+ /*
+ * For TRACE_EVENT() events, the print_fmt is not
+ * safe to use if the array has delta offsets
+ * Force printing via the fields.
+ */
+ if ((tr->text_delta || tr->data_delta) &&
+ event->type > __TRACE_LAST_TYPE)
+ return print_event_fields(iter, event);
+
return event->funcs->trace(iter, sym_flags, event);
}
@@ -5225,6 +5069,9 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
cpumask_var_t tracing_cpumask_new;
int err;
+ if (count == 0 || count > KMALLOC_MAX_SIZE)
+ return -EINVAL;
+
if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM;
@@ -5261,7 +5108,8 @@ static int tracing_trace_options_show(struct seq_file *m, void *v)
u32 tracer_flags;
int i;
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
+
tracer_flags = tr->current_trace->flags->val;
trace_opts = tr->current_trace->flags->opts;
@@ -5278,7 +5126,6 @@ static int tracing_trace_options_show(struct seq_file *m, void *v)
else
seq_printf(m, "no%s\n", trace_opts[i].name);
}
- mutex_unlock(&trace_types_lock);
return 0;
}
@@ -5671,6 +5518,8 @@ static const char readme_msg[] =
"\t efield: For event probes ('e' types), the field is on of the fields\n"
"\t of the <attached-group>/<attached-event>.\n"
#endif
+ " set_event\t\t- Enables events by name written into it\n"
+ "\t\t\t Can enable module events via: :mod:<module>\n"
" events/\t\t- Directory containing all trace event subsystems:\n"
" enable\t\t- Write 0/1 to enable/disable tracing of all events\n"
" events/<system>/\t- Directory containing all trace events for <system>:\n"
@@ -5943,7 +5792,7 @@ trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start,
return;
}
- mutex_lock(&trace_eval_mutex);
+ guard(mutex)(&trace_eval_mutex);
if (!trace_eval_maps)
trace_eval_maps = map_array;
@@ -5967,8 +5816,6 @@ trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start,
map_array++;
}
memset(map_array, 0, sizeof(*map_array));
-
- mutex_unlock(&trace_eval_mutex);
}
static void trace_create_eval_file(struct dentry *d_tracer)
@@ -6130,26 +5977,15 @@ static int __tracing_resize_ring_buffer(struct trace_array *tr,
ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
unsigned long size, int cpu_id)
{
- int ret;
-
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
if (cpu_id != RING_BUFFER_ALL_CPUS) {
/* make sure, this cpu is enabled in the mask */
- if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) {
- ret = -EINVAL;
- goto out;
- }
+ if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask))
+ return -EINVAL;
}
- ret = __tracing_resize_ring_buffer(tr, size, cpu_id);
- if (ret < 0)
- ret = -ENOMEM;
-
-out:
- mutex_unlock(&trace_types_lock);
-
- return ret;
+ return __tracing_resize_ring_buffer(tr, size, cpu_id);
}
static void update_last_data(struct trace_array *tr)
@@ -6240,9 +6076,9 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf)
#ifdef CONFIG_TRACER_MAX_TRACE
bool had_max_tr;
#endif
- int ret = 0;
+ int ret;
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
update_last_data(tr);
@@ -6250,7 +6086,7 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf)
ret = __tracing_resize_ring_buffer(tr, trace_buf_size,
RING_BUFFER_ALL_CPUS);
if (ret < 0)
- goto out;
+ return ret;
ret = 0;
}
@@ -6258,43 +6094,37 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf)
if (strcmp(t->name, buf) == 0)
break;
}
- if (!t) {
- ret = -EINVAL;
- goto out;
- }
+ if (!t)
+ return -EINVAL;
+
if (t == tr->current_trace)
- goto out;
+ return 0;
#ifdef CONFIG_TRACER_SNAPSHOT
if (t->use_max_tr) {
local_irq_disable();
arch_spin_lock(&tr->max_lock);
- if (tr->cond_snapshot)
- ret = -EBUSY;
+ ret = tr->cond_snapshot ? -EBUSY : 0;
arch_spin_unlock(&tr->max_lock);
local_irq_enable();
if (ret)
- goto out;
+ return ret;
}
#endif
/* Some tracers won't work on kernel command line */
if (system_state < SYSTEM_RUNNING && t->noboot) {
pr_warn("Tracer '%s' is not allowed on command line, ignored\n",
t->name);
- goto out;
+ return -EINVAL;
}
/* Some tracers are only allowed for the top level buffer */
- if (!trace_ok_for_array(t, tr)) {
- ret = -EINVAL;
- goto out;
- }
+ if (!trace_ok_for_array(t, tr))
+ return -EINVAL;
/* If trace pipe files are being read, we can't change the tracer */
- if (tr->trace_ref) {
- ret = -EBUSY;
- goto out;
- }
+ if (tr->trace_ref)
+ return -EBUSY;
trace_branch_disable();
@@ -6325,7 +6155,7 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf)
if (!had_max_tr && t->use_max_tr) {
ret = tracing_arm_snapshot_locked(tr);
if (ret)
- goto out;
+ return ret;
}
#else
tr->current_trace = &nop_trace;
@@ -6338,17 +6168,15 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf)
if (t->use_max_tr)
tracing_disarm_snapshot(tr);
#endif
- goto out;
+ return ret;
}
}
tr->current_trace = t;
tr->current_trace->enabled++;
trace_branch_enable(tr);
- out:
- mutex_unlock(&trace_types_lock);
- return ret;
+ return 0;
}
static ssize_t
@@ -6426,22 +6254,18 @@ tracing_thresh_write(struct file *filp, const char __user *ubuf,
struct trace_array *tr = filp->private_data;
int ret;
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos);
if (ret < 0)
- goto out;
+ return ret;
if (tr->current_trace->update_thresh) {
ret = tr->current_trace->update_thresh(tr);
if (ret < 0)
- goto out;
+ return ret;
}
- ret = cnt;
-out:
- mutex_unlock(&trace_types_lock);
-
- return ret;
+ return cnt;
}
#ifdef CONFIG_TRACER_MAX_TRACE
@@ -6660,31 +6484,29 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
* This is just a matter of traces coherency, the ring buffer itself
* is protected.
*/
- mutex_lock(&iter->mutex);
+ guard(mutex)(&iter->mutex);
/* return any leftover data */
sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
if (sret != -EBUSY)
- goto out;
+ return sret;
trace_seq_init(&iter->seq);
if (iter->trace->read) {
sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
if (sret)
- goto out;
+ return sret;
}
waitagain:
sret = tracing_wait_pipe(filp);
if (sret <= 0)
- goto out;
+ return sret;
/* stop when tracing is finished */
- if (trace_empty(iter)) {
- sret = 0;
- goto out;
- }
+ if (trace_empty(iter))
+ return 0;
if (cnt >= TRACE_SEQ_BUFFER_SIZE)
cnt = TRACE_SEQ_BUFFER_SIZE - 1;
@@ -6748,9 +6570,6 @@ waitagain:
if (sret == -EBUSY)
goto waitagain;
-out:
- mutex_unlock(&iter->mutex);
-
return sret;
}
@@ -7342,25 +7161,19 @@ u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_eve
*/
int tracing_set_filter_buffering(struct trace_array *tr, bool set)
{
- int ret = 0;
-
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
if (set && tr->no_filter_buffering_ref++)
- goto out;
+ return 0;
if (!set) {
- if (WARN_ON_ONCE(!tr->no_filter_buffering_ref)) {
- ret = -EINVAL;
- goto out;
- }
+ if (WARN_ON_ONCE(!tr->no_filter_buffering_ref))
+ return -EINVAL;
--tr->no_filter_buffering_ref;
}
- out:
- mutex_unlock(&trace_types_lock);
- return ret;
+ return 0;
}
struct ftrace_buffer_info {
@@ -7436,12 +7249,10 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
if (ret)
return ret;
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
- if (tr->current_trace->use_max_tr) {
- ret = -EBUSY;
- goto out;
- }
+ if (tr->current_trace->use_max_tr)
+ return -EBUSY;
local_irq_disable();
arch_spin_lock(&tr->max_lock);
@@ -7450,24 +7261,20 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
arch_spin_unlock(&tr->max_lock);
local_irq_enable();
if (ret)
- goto out;
+ return ret;
switch (val) {
case 0:
- if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
- ret = -EINVAL;
- break;
- }
+ if (iter->cpu_file != RING_BUFFER_ALL_CPUS)
+ return -EINVAL;
if (tr->allocated_snapshot)
free_snapshot(tr);
break;
case 1:
/* Only allow per-cpu swap if the ring buffer supports it */
#ifndef CONFIG_RING_BUFFER_ALLOW_SWAP
- if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
- ret = -EINVAL;
- break;
- }
+ if (iter->cpu_file != RING_BUFFER_ALL_CPUS)
+ return -EINVAL;
#endif
if (tr->allocated_snapshot)
ret = resize_buffer_duplicate_size(&tr->max_buffer,
@@ -7475,7 +7282,7 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
ret = tracing_arm_snapshot_locked(tr);
if (ret)
- break;
+ return ret;
/* Now, we're going to swap */
if (iter->cpu_file == RING_BUFFER_ALL_CPUS) {
@@ -7502,8 +7309,7 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
*ppos += cnt;
ret = cnt;
}
-out:
- mutex_unlock(&trace_types_lock);
+
return ret;
}
@@ -7889,12 +7695,11 @@ void tracing_log_err(struct trace_array *tr,
len += sizeof(CMD_PREFIX) + 2 * sizeof("\n") + strlen(cmd) + 1;
- mutex_lock(&tracing_err_log_lock);
+ guard(mutex)(&tracing_err_log_lock);
+
err = get_tracing_log_err(tr, len);
- if (PTR_ERR(err) == -ENOMEM) {
- mutex_unlock(&tracing_err_log_lock);
+ if (PTR_ERR(err) == -ENOMEM)
return;
- }
snprintf(err->loc, TRACING_LOG_LOC_MAX, "%s: error: ", loc);
snprintf(err->cmd, len, "\n" CMD_PREFIX "%s\n", cmd);
@@ -7905,7 +7710,6 @@ void tracing_log_err(struct trace_array *tr,
err->info.ts = local_clock();
list_add_tail(&err->list, &tr->err_log);
- mutex_unlock(&tracing_err_log_lock);
}
static void clear_tracing_err_log(struct trace_array *tr)
@@ -8475,6 +8279,10 @@ static int tracing_buffers_mmap(struct file *filp, struct vm_area_struct *vma)
struct trace_iterator *iter = &info->iter;
int ret = 0;
+ /* Currently the boot mapped buffer is not supported for mmap */
+ if (iter->tr->flags & TRACE_ARRAY_FL_BOOT)
+ return -ENODEV;
+
ret = get_snapshot_map(iter->tr);
if (ret)
return ret;
@@ -9601,6 +9409,10 @@ trace_array_create_systems(const char *name, const char *systems,
INIT_LIST_HEAD(&tr->hist_vars);
INIT_LIST_HEAD(&tr->err_log);
+#ifdef CONFIG_MODULES
+ INIT_LIST_HEAD(&tr->mod_events);
+#endif
+
if (allocate_trace_buffers(tr, trace_buf_size) < 0)
goto out_free_tr;
@@ -9649,20 +9461,17 @@ static int instance_mkdir(const char *name)
struct trace_array *tr;
int ret;
- mutex_lock(&event_mutex);
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&event_mutex);
+ guard(mutex)(&trace_types_lock);
ret = -EEXIST;
if (trace_array_find(name))
- goto out_unlock;
+ return -EEXIST;
tr = trace_array_create(name);
ret = PTR_ERR_OR_ZERO(tr);
-out_unlock:
- mutex_unlock(&trace_types_lock);
- mutex_unlock(&event_mutex);
return ret;
}
@@ -9712,24 +9521,23 @@ struct trace_array *trace_array_get_by_name(const char *name, const char *system
{
struct trace_array *tr;
- mutex_lock(&event_mutex);
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&event_mutex);
+ guard(mutex)(&trace_types_lock);
list_for_each_entry(tr, &ftrace_trace_arrays, list) {
- if (tr->name && strcmp(tr->name, name) == 0)
- goto out_unlock;
+ if (tr->name && strcmp(tr->name, name) == 0) {
+ tr->ref++;
+ return tr;
+ }
}
tr = trace_array_create_systems(name, systems, 0, 0);
if (IS_ERR(tr))
tr = NULL;
-out_unlock:
- if (tr)
+ else
tr->ref++;
- mutex_unlock(&trace_types_lock);
- mutex_unlock(&event_mutex);
return tr;
}
EXPORT_SYMBOL_GPL(trace_array_get_by_name);
@@ -9780,48 +9588,36 @@ static int __remove_instance(struct trace_array *tr)
int trace_array_destroy(struct trace_array *this_tr)
{
struct trace_array *tr;
- int ret;
if (!this_tr)
return -EINVAL;
- mutex_lock(&event_mutex);
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&event_mutex);
+ guard(mutex)(&trace_types_lock);
- ret = -ENODEV;
/* Making sure trace array exists before destroying it. */
list_for_each_entry(tr, &ftrace_trace_arrays, list) {
- if (tr == this_tr) {
- ret = __remove_instance(tr);
- break;
- }
+ if (tr == this_tr)
+ return __remove_instance(tr);
}
- mutex_unlock(&trace_types_lock);
- mutex_unlock(&event_mutex);
-
- return ret;
+ return -ENODEV;
}
EXPORT_SYMBOL_GPL(trace_array_destroy);
static int instance_rmdir(const char *name)
{
struct trace_array *tr;
- int ret;
- mutex_lock(&event_mutex);
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&event_mutex);
+ guard(mutex)(&trace_types_lock);
- ret = -ENODEV;
tr = trace_array_find(name);
- if (tr)
- ret = __remove_instance(tr);
-
- mutex_unlock(&trace_types_lock);
- mutex_unlock(&event_mutex);
+ if (!tr)
+ return -ENODEV;
- return ret;
+ return __remove_instance(tr);
}
static __init void create_trace_instances(struct dentry *d_tracer)
@@ -9834,19 +9630,16 @@ static __init void create_trace_instances(struct dentry *d_tracer)
if (MEM_FAIL(!trace_instance_dir, "Failed to create instances directory\n"))
return;
- mutex_lock(&event_mutex);
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&event_mutex);
+ guard(mutex)(&trace_types_lock);
list_for_each_entry(tr, &ftrace_trace_arrays, list) {
if (!tr->name)
continue;
if (MEM_FAIL(trace_array_create_dir(tr) < 0,
"Failed to create instance directory\n"))
- break;
+ return;
}
-
- mutex_unlock(&trace_types_lock);
- mutex_unlock(&event_mutex);
}
static void
@@ -10036,6 +9829,24 @@ late_initcall_sync(trace_eval_sync);
#ifdef CONFIG_MODULES
+
+bool module_exists(const char *module)
+{
+ /* All modules have the symbol __this_module */
+ static const char this_mod[] = "__this_module";
+ char modname[MAX_PARAM_PREFIX_LEN + sizeof(this_mod) + 2];
+ unsigned long val;
+ int n;
+
+ n = snprintf(modname, sizeof(modname), "%s:%s", module, this_mod);
+
+ if (n > sizeof(modname) - 1)
+ return false;
+
+ val = module_kallsyms_lookup_name(modname);
+ return val != 0;
+}
+
static void trace_module_add_evals(struct module *mod)
{
if (!mod->num_trace_evals)
@@ -10060,7 +9871,7 @@ static void trace_module_remove_evals(struct module *mod)
if (!mod->num_trace_evals)
return;
- mutex_lock(&trace_eval_mutex);
+ guard(mutex)(&trace_eval_mutex);
map = trace_eval_maps;
@@ -10072,12 +9883,10 @@ static void trace_module_remove_evals(struct module *mod)
map = map->tail.next;
}
if (!map)
- goto out;
+ return;
*last = trace_eval_jmp_to_tail(map)->tail.next;
kfree(map);
- out:
- mutex_unlock(&trace_eval_mutex);
}
#else
static inline void trace_module_remove_evals(struct module *mod) { }
@@ -10750,6 +10559,10 @@ __init static int tracer_alloc_buffers(void)
#endif
ftrace_init_global_array_ops(&global_trace);
+#ifdef CONFIG_MODULES
+ INIT_LIST_HEAD(&global_trace.mod_events);
+#endif
+
init_trace_flags_index(&global_trace);
register_tracer(&nop_trace);
@@ -10777,8 +10590,6 @@ __init static int tracer_alloc_buffers(void)
register_snapshot_cmd();
- test_can_verify();
-
return 0;
out_free_pipe_cpumask:
@@ -10797,6 +10608,14 @@ out:
return ret;
}
+#ifdef CONFIG_FUNCTION_TRACER
+/* Used to set module cached ftrace filtering at boot up */
+__init struct trace_array *trace_get_global_array(void)
+{
+ return &global_trace;
+}
+#endif
+
void __init ftrace_boot_snapshot(void)
{
#ifdef CONFIG_TRACER_MAX_TRACE