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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c193
1 files changed, 133 insertions, 60 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 64a4dde073ef..2b4ded753367 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -199,7 +199,7 @@ static int boot_snapshot_index;
static int __init set_cmdline_ftrace(char *str)
{
- strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
+ strscpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
ring_buffer_expanded = true;
@@ -284,7 +284,7 @@ static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata;
static int __init set_trace_boot_options(char *str)
{
- strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
+ strscpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
return 1;
}
__setup("trace_options=", set_trace_boot_options);
@@ -294,7 +294,7 @@ static char *trace_boot_clock __initdata;
static int __init set_trace_boot_clock(char *str)
{
- strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE);
+ strscpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE);
trace_boot_clock = trace_boot_clock_buf;
return 1;
}
@@ -1928,9 +1928,10 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
* place on this CPU. We fail to record, but we reset
* the max trace buffer (no one writes directly to it)
* and flag that it failed.
+ * Another reason is resize is in progress.
*/
trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_,
- "Failed to swap buffers due to commit in progress\n");
+ "Failed to swap buffers due to commit or resize in progress\n");
}
WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY);
@@ -2546,7 +2547,7 @@ static void __trace_find_cmdline(int pid, char comm[])
if (map != NO_CMDLINE_MAP) {
tpid = savedcmd->map_cmdline_to_pid[map];
if (tpid == pid) {
- strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN);
+ strscpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN);
return;
}
}
@@ -3155,16 +3156,16 @@ static void __ftrace_trace_stack(struct trace_buffer *buffer,
nr_entries = stack_trace_save(fstack->calls, size, skip);
}
- size = nr_entries * sizeof(unsigned long);
event = __trace_buffer_lock_reserve(buffer, TRACE_STACK,
- (sizeof(*entry) - sizeof(entry->caller)) + size,
+ struct_size(entry, caller, nr_entries),
trace_ctx);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
- memcpy(&entry->caller, fstack->calls, size);
entry->size = nr_entries;
+ memcpy(&entry->caller, fstack->calls,
+ flex_array_size(entry, caller, nr_entries));
if (!call_filter_check_discard(call, entry, buffer, event))
__buffer_unlock_commit(buffer, event);
@@ -4188,15 +4189,16 @@ static void *s_start(struct seq_file *m, loff_t *pos)
loff_t l = 0;
int cpu;
- /*
- * copy the tracer to avoid using a global lock all around.
- * iter->trace is a copy of current_trace, the pointer to the
- * name may be used instead of a strcmp(), as iter->trace->name
- * will point to the same string as current_trace->name.
- */
mutex_lock(&trace_types_lock);
- if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name))
- *iter->trace = *tr->current_trace;
+ if (unlikely(tr->current_trace != iter->trace)) {
+ /* Close iter->trace before switching to the new current tracer */
+ if (iter->trace->close)
+ iter->trace->close(iter);
+ iter->trace = tr->current_trace;
+ /* Reopen the new current tracer */
+ if (iter->trace->open)
+ iter->trace->open(iter);
+ }
mutex_unlock(&trace_types_lock);
#ifdef CONFIG_TRACER_MAX_TRACE
@@ -4804,6 +4806,25 @@ static const struct seq_operations tracer_seq_ops = {
.show = s_show,
};
+/*
+ * Note, as iter itself can be allocated and freed in different
+ * ways, this function is only used to free its content, and not
+ * the iterator itself. The only requirement to all the allocations
+ * is that it must zero all fields (kzalloc), as freeing works with
+ * ethier allocated content or NULL.
+ */
+static void free_trace_iter_content(struct trace_iterator *iter)
+{
+ /* The fmt is either NULL, allocated or points to static_fmt_buf */
+ if (iter->fmt != static_fmt_buf)
+ kfree(iter->fmt);
+
+ kfree(iter->temp);
+ kfree(iter->buffer_iter);
+ mutex_destroy(&iter->mutex);
+ free_cpumask_var(iter->started);
+}
+
static struct trace_iterator *
__tracing_open(struct inode *inode, struct file *file, bool snapshot)
{
@@ -4845,16 +4866,8 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
iter->fmt = NULL;
iter->fmt_size = 0;
- /*
- * We make a copy of the current tracer to avoid concurrent
- * changes on it while we are reading.
- */
mutex_lock(&trace_types_lock);
- iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL);
- if (!iter->trace)
- goto fail;
-
- *iter->trace = *tr->current_trace;
+ iter->trace = tr->current_trace;
if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL))
goto fail;
@@ -4919,9 +4932,7 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
fail:
mutex_unlock(&trace_types_lock);
- kfree(iter->trace);
- kfree(iter->temp);
- kfree(iter->buffer_iter);
+ free_trace_iter_content(iter);
release:
seq_release_private(inode, file);
return ERR_PTR(-ENOMEM);
@@ -5000,12 +5011,7 @@ static int tracing_release(struct inode *inode, struct file *file)
mutex_unlock(&trace_types_lock);
- mutex_destroy(&iter->mutex);
- free_cpumask_var(iter->started);
- kfree(iter->fmt);
- kfree(iter->temp);
- kfree(iter->trace);
- kfree(iter->buffer_iter);
+ free_trace_iter_content(iter);
seq_release_private(inode, file);
return 0;
@@ -5199,7 +5205,7 @@ static const struct file_operations tracing_fops = {
.open = tracing_open,
.read = seq_read,
.read_iter = seq_read_iter,
- .splice_read = generic_file_splice_read,
+ .splice_read = copy_splice_read,
.write = tracing_write_stub,
.llseek = tracing_lseek,
.release = tracing_release,
@@ -5259,11 +5265,17 @@ int tracing_set_cpumask(struct trace_array *tr,
!cpumask_test_cpu(cpu, tracing_cpumask_new)) {
atomic_inc(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled);
ring_buffer_record_disable_cpu(tr->array_buffer.buffer, cpu);
+#ifdef CONFIG_TRACER_MAX_TRACE
+ ring_buffer_record_disable_cpu(tr->max_buffer.buffer, cpu);
+#endif
}
if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) &&
cpumask_test_cpu(cpu, tracing_cpumask_new)) {
atomic_dec(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled);
ring_buffer_record_enable_cpu(tr->array_buffer.buffer, cpu);
+#ifdef CONFIG_TRACER_MAX_TRACE
+ ring_buffer_record_enable_cpu(tr->max_buffer.buffer, cpu);
+#endif
}
}
arch_spin_unlock(&tr->max_lock);
@@ -5672,10 +5684,17 @@ static const char readme_msg[] =
" 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)
+#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) || \
+ defined(CONFIG_FPROBE_EVENTS)
"\t accepts: event-definitions (one definition per line)\n"
+#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS)
"\t Format: p[:[<group>/][<event>]] <place> [<args>]\n"
"\t r[maxactive][:[<group>/][<event>]] <place> [<args>]\n"
+#endif
+#ifdef CONFIG_FPROBE_EVENTS
+ "\t f[:[<group>/][<event>]] <func-name>[%return] [<args>]\n"
+ "\t t[:[<group>/][<event>]] <tracepoint> [<args>]\n"
+#endif
#ifdef CONFIG_HIST_TRIGGERS
"\t s:[synthetic/]<event> <field> [<field>]\n"
#endif
@@ -5691,7 +5710,12 @@ static const char readme_msg[] =
"\t args: <name>=fetcharg[:type]\n"
"\t fetcharg: (%<register>|$<efield>), @<address>, @<symbol>[+|-<offset>],\n"
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
+#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
"\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
+ "\t <argname>[->field[->field|.field...]],\n"
+#else
+ "\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
+#endif
#else
"\t $stack<index>, $stack, $retval, $comm,\n"
#endif
@@ -6276,6 +6300,15 @@ static void set_buffer_entries(struct array_buffer *buf, unsigned long val)
per_cpu_ptr(buf->data, cpu)->entries = val;
}
+static void update_buffer_entries(struct array_buffer *buf, int cpu)
+{
+ if (cpu == RING_BUFFER_ALL_CPUS) {
+ set_buffer_entries(buf, ring_buffer_size(buf->buffer, 0));
+ } else {
+ per_cpu_ptr(buf->data, cpu)->entries = ring_buffer_size(buf->buffer, cpu);
+ }
+}
+
#ifdef CONFIG_TRACER_MAX_TRACE
/* resize @tr's buffer to the size of @size_tr's entries */
static int resize_buffer_duplicate_size(struct array_buffer *trace_buf,
@@ -6354,18 +6387,12 @@ static int __tracing_resize_ring_buffer(struct trace_array *tr,
return ret;
}
- if (cpu == RING_BUFFER_ALL_CPUS)
- set_buffer_entries(&tr->max_buffer, size);
- else
- per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size;
+ update_buffer_entries(&tr->max_buffer, cpu);
out:
#endif /* CONFIG_TRACER_MAX_TRACE */
- if (cpu == RING_BUFFER_ALL_CPUS)
- set_buffer_entries(&tr->array_buffer, size);
- else
- per_cpu_ptr(tr->array_buffer.data, cpu)->entries = size;
+ update_buffer_entries(&tr->array_buffer, cpu);
return ret;
}
@@ -6676,10 +6703,36 @@ tracing_max_lat_write(struct file *filp, const char __user *ubuf,
#endif
+static int open_pipe_on_cpu(struct trace_array *tr, int cpu)
+{
+ if (cpu == RING_BUFFER_ALL_CPUS) {
+ if (cpumask_empty(tr->pipe_cpumask)) {
+ cpumask_setall(tr->pipe_cpumask);
+ return 0;
+ }
+ } else if (!cpumask_test_cpu(cpu, tr->pipe_cpumask)) {
+ cpumask_set_cpu(cpu, tr->pipe_cpumask);
+ return 0;
+ }
+ return -EBUSY;
+}
+
+static void close_pipe_on_cpu(struct trace_array *tr, int cpu)
+{
+ if (cpu == RING_BUFFER_ALL_CPUS) {
+ WARN_ON(!cpumask_full(tr->pipe_cpumask));
+ cpumask_clear(tr->pipe_cpumask);
+ } else {
+ WARN_ON(!cpumask_test_cpu(cpu, tr->pipe_cpumask));
+ cpumask_clear_cpu(cpu, tr->pipe_cpumask);
+ }
+}
+
static int tracing_open_pipe(struct inode *inode, struct file *filp)
{
struct trace_array *tr = inode->i_private;
struct trace_iterator *iter;
+ int cpu;
int ret;
ret = tracing_check_open_get_tr(tr);
@@ -6687,13 +6740,16 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
return ret;
mutex_lock(&trace_types_lock);
+ cpu = tracing_get_cpu(inode);
+ ret = open_pipe_on_cpu(tr, cpu);
+ if (ret)
+ goto fail_pipe_on_cpu;
/* create a buffer to store the information to pass to userspace */
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
if (!iter) {
ret = -ENOMEM;
- __trace_array_put(tr);
- goto out;
+ goto fail_alloc_iter;
}
trace_seq_init(&iter->seq);
@@ -6716,7 +6772,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
iter->tr = tr;
iter->array_buffer = &tr->array_buffer;
- iter->cpu_file = tracing_get_cpu(inode);
+ iter->cpu_file = cpu;
mutex_init(&iter->mutex);
filp->private_data = iter;
@@ -6726,12 +6782,15 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
nonseekable_open(inode, filp);
tr->trace_ref++;
-out:
+
mutex_unlock(&trace_types_lock);
return ret;
fail:
kfree(iter);
+fail_alloc_iter:
+ close_pipe_on_cpu(tr, cpu);
+fail_pipe_on_cpu:
__trace_array_put(tr);
mutex_unlock(&trace_types_lock);
return ret;
@@ -6748,12 +6807,10 @@ static int tracing_release_pipe(struct inode *inode, struct file *file)
if (iter->trace->pipe_close)
iter->trace->pipe_close(iter);
-
+ close_pipe_on_cpu(tr, iter->cpu_file);
mutex_unlock(&trace_types_lock);
- free_cpumask_var(iter->started);
- kfree(iter->fmt);
- mutex_destroy(&iter->mutex);
+ free_trace_iter_content(iter);
kfree(iter);
trace_array_put(tr);
@@ -7543,6 +7600,11 @@ out:
return ret;
}
+static void tracing_swap_cpu_buffer(void *tr)
+{
+ update_max_tr_single((struct trace_array *)tr, current, smp_processor_id());
+}
+
static ssize_t
tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
loff_t *ppos)
@@ -7601,13 +7663,15 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
ret = tracing_alloc_snapshot_instance(tr);
if (ret < 0)
break;
- local_irq_disable();
/* Now, we're going to swap */
- if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
+ if (iter->cpu_file == RING_BUFFER_ALL_CPUS) {
+ local_irq_disable();
update_max_tr(tr, current, smp_processor_id(), NULL);
- else
- update_max_tr_single(tr, current, iter->cpu_file);
- local_irq_enable();
+ local_irq_enable();
+ } else {
+ smp_call_function_single(iter->cpu_file, tracing_swap_cpu_buffer,
+ (void *)tr, 1);
+ }
break;
default:
if (tr->allocated_snapshot) {
@@ -8135,7 +8199,7 @@ static const struct file_operations tracing_err_log_fops = {
.open = tracing_err_log_open,
.write = tracing_err_log_write,
.read = seq_read,
- .llseek = seq_lseek,
+ .llseek = tracing_lseek,
.release = tracing_err_log_release,
};
@@ -9411,6 +9475,9 @@ static struct trace_array *trace_array_create(const char *name)
if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL))
goto out_free_tr;
+ if (!zalloc_cpumask_var(&tr->pipe_cpumask, GFP_KERNEL))
+ goto out_free_tr;
+
tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS;
cpumask_copy(tr->tracing_cpumask, cpu_all_mask);
@@ -9452,6 +9519,7 @@ static struct trace_array *trace_array_create(const char *name)
out_free_tr:
ftrace_free_ftrace_ops(tr);
free_trace_buffers(tr);
+ free_cpumask_var(tr->pipe_cpumask);
free_cpumask_var(tr->tracing_cpumask);
kfree(tr->name);
kfree(tr);
@@ -9554,6 +9622,7 @@ static int __remove_instance(struct trace_array *tr)
}
kfree(tr->topts);
+ free_cpumask_var(tr->pipe_cpumask);
free_cpumask_var(tr->tracing_cpumask);
kfree(tr->name);
kfree(tr);
@@ -10351,12 +10420,14 @@ __init static int tracer_alloc_buffers(void)
if (trace_create_savedcmd() < 0)
goto out_free_temp_buffer;
+ if (!zalloc_cpumask_var(&global_trace.pipe_cpumask, GFP_KERNEL))
+ goto out_free_savedcmd;
+
/* TODO: make the number of buffers hot pluggable with CPUS */
if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) {
MEM_FAIL(1, "tracer: failed to allocate ring buffer!\n");
- goto out_free_savedcmd;
+ goto out_free_pipe_cpumask;
}
-
if (global_trace.buffer_disabled)
tracing_off();
@@ -10409,6 +10480,8 @@ __init static int tracer_alloc_buffers(void)
return 0;
+out_free_pipe_cpumask:
+ free_cpumask_var(global_trace.pipe_cpumask);
out_free_savedcmd:
free_saved_cmdlines_buffer(savedcmd);
out_free_temp_buffer: