Thread (28 messages) 28 messages, 2 authors, 2021-06-22

Re: [PATCH V4 06/12] trace: Add a generic function to read/write u64 values from tracefs

From: Steven Rostedt <rostedt@goodmis.org>
Date: 2021-06-18 16:56:58
Also in: lkml

On Tue, 15 Jun 2021 11:28:45 +0200
Daniel Bristot de Oliveira [off-list ref] wrote:
+static ssize_t
+trace_min_max_read(struct file *filp, char __user *ubuf, size_t cnt,
+		      loff_t *ppos)
+{
+	struct trace_min_max_param *param = filp->private_data;
+	char buf[ULL_STR_SIZE];
+	u64 val;
+        int len;
White space issue above?
+
+        if (!param)
+                return -EFAULT;
And above here too?

+
+	val = *param->val;
+
+        if (cnt > sizeof(buf))
+                cnt = sizeof(buf);
+
+        len = snprintf(buf, sizeof(buf), "%llu\n", val);
+
+        return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
Egad, this entire patch is filled with whitespace issues!

Please check your other patches too.
+}
+
+
+#define ULL_STR_SIZE		22	/* 20 digits max */
Nit. I'd make this 24, just to be integer aligned. I mean, it's used as:


trace_min_max_read(struct file *filp, char __user *ubuf, size_t cnt,
		      loff_t *ppos)
{
	struct trace_min_max_param *param = filp->private_data;
	char buf[ULL_STR_SIZE];
	u64 val;
	int len;

Probably should reverse the above as well, that way if you do have
ULL_STR_SIZE as 24, then the int len, will fit right in before the u64
val. Although, I think compilers are free to optimize that too :-/

-- Steve
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help