Merge tag 'trace-seq-buf-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/roste...

[firefly-linux-kernel-4.4.55.git] / kernel / trace / trace.c

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 26facec4625e205ce2cbed6dbc1bad13e3ec9a40..1af4f8f2ab5d167d01d1a13af72f0250fe4377ff 100644 (file)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1078,13 +1078,14 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
 }
 #endif /* CONFIG_TRACER_MAX_TRACE */
 
-static int wait_on_pipe(struct trace_iterator *iter)
+static int wait_on_pipe(struct trace_iterator *iter, bool full)
 {
        /* Iterators are static, they should be filled or empty */
        if (trace_buffer_iter(iter, iter->cpu_file))
                return 0;
 
-       return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file);
+       return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file,
+                               full);
 }
 
 #ifdef CONFIG_FTRACE_STARTUP_TEST
@@ -2159,9 +2160,7 @@ __trace_array_vprintk(struct ring_buffer *buffer,
                goto out;
        }
 
-       len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args);
-       if (len > TRACE_BUF_SIZE)
-               goto out;
+       len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args);
 
        local_save_flags(flags);
        size = sizeof(*entry) + len + 1;
@@ -2172,8 +2171,7 @@ __trace_array_vprintk(struct ring_buffer *buffer,
        entry = ring_buffer_event_data(event);
        entry->ip = ip;
 
-       memcpy(&entry->buf, tbuffer, len);
-       entry->buf[len] = '\0';
+       memcpy(&entry->buf, tbuffer, len + 1);
        if (!call_filter_check_discard(call, entry, buffer, event)) {
                __buffer_unlock_commit(buffer, event);
                ftrace_trace_stack(buffer, flags, 6, pc);
@@ -4439,15 +4437,12 @@ static int tracing_wait_pipe(struct file *filp)
 
                mutex_unlock(&iter->mutex);
 
-               ret = wait_on_pipe(iter);
+               ret = wait_on_pipe(iter, false);
 
                mutex_lock(&iter->mutex);
 
                if (ret)
                        return ret;
-
-               if (signal_pending(current))
-                       return -EINTR;
        }
 
        return 1;
@@ -5390,16 +5385,12 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
                                goto out_unlock;
                        }
                        mutex_unlock(&trace_types_lock);
-                       ret = wait_on_pipe(iter);
+                       ret = wait_on_pipe(iter, false);
                        mutex_lock(&trace_types_lock);
                        if (ret) {
                                size = ret;
                                goto out_unlock;
                        }
-                       if (signal_pending(current)) {
-                               size = -EINTR;
-                               goto out_unlock;
-                       }
                        goto again;
                }
                size = 0;
@@ -5518,7 +5509,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
        };
        struct buffer_ref *ref;
        int entries, size, i;
-       ssize_t ret;
+       ssize_t ret = 0;
 
        mutex_lock(&trace_types_lock);
 
@@ -5556,13 +5547,16 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                int r;
 
                ref = kzalloc(sizeof(*ref), GFP_KERNEL);
-               if (!ref)
+               if (!ref) {
+                       ret = -ENOMEM;
                        break;
+               }
 
                ref->ref = 1;
                ref->buffer = iter->trace_buffer->buffer;
                ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file);
                if (!ref->page) {
+                       ret = -ENOMEM;
                        kfree(ref);
                        break;
                }
@@ -5600,19 +5594,19 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 
        /* did we read anything? */
        if (!spd.nr_pages) {
+               if (ret)
+                       goto out;
+
                if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) {
                        ret = -EAGAIN;
                        goto out;
                }
                mutex_unlock(&trace_types_lock);
-               ret = wait_on_pipe(iter);
+               ret = wait_on_pipe(iter, true);
                mutex_lock(&trace_types_lock);
                if (ret)
                        goto out;
-               if (signal_pending(current)) {
-                       ret = -EINTR;
-                       goto out;
-               }
+
                goto again;
        }
 
@@ -6439,7 +6433,7 @@ static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t m
        int ret;
 
        /* Paranoid: Make sure the parent is the "instances" directory */
-       parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias);
+       parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias);
        if (WARN_ON_ONCE(parent != trace_instance_dir))
                return -ENOENT;
 
@@ -6466,7 +6460,7 @@ static int instance_rmdir(struct inode *inode, struct dentry *dentry)
        int ret;
 
        /* Paranoid: Make sure the parent is the "instances" directory */
-       parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias);
+       parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias);
        if (WARN_ON_ONCE(parent != trace_instance_dir))
                return -ENOENT;