buffer

source/buffer/trace_buffer.c

@@ -0,0 +1,215 @@
+/*
+ * diagnose-tools 工具通用调试缓冲区模块
+ * 这是为了解决procfs/trace的问题而编写 
+ *
+ * Copyright (C) 20２０ Alibaba Ltd.
+ *
+ * 作者： Baoyou Xie <baoyou.xie@linux.alibaba.com>
+ *
+ * License terms: GNU General Public License (GPL) version 3
+ *
+ */
+
+#include <linux/vmalloc.h>
+
+// #include "internal.h"
+#include "trace_buffer.h"
+
+int init_diag_trace_buffer(struct diag_trace_buffer *buffer,
+	unsigned int buf_size)
+{
+	int ret = -ENOMEM;
+	char *buf1 = NULL, *buf2 = NULL;
+
+	ret = -EINVAL;
+	if (buf_size < 10 * DIAG_TRACE_BUF_SIZE)
+		return ret;
+
+	buf1 = vmalloc(buf_size);
+	if (!buf1)
+		goto out_nomem;
+
+	buf2 = vmalloc(buf_size);
+	if (!buf2)
+		goto out_nomem;
+
+	memset(buf1, 0, buf_size);
+	memset(buf2, 0, buf_size);
+	memset(buffer, 0, sizeof(struct diag_trace_buffer));
+	buffer->buf_size = buf_size;
+	buffer->buffer.data = buf1;
+	spin_lock_init(&buffer->buffer.lock);
+	mutex_init(&buffer->buffer.mutex);
+	buffer->product.data = buf2;
+
+ 	ret = 0;
+	return ret;
+out_nomem:
+	if (buf1)
+		vfree(buf1);
+	if (buf2)
+		vfree(buf2);
+	
+	return ret;
+}
+
+void destroy_diag_trace_buffer(struct diag_trace_buffer *buffer)
+{
+	if (buffer->buffer.data)
+		vfree(buffer->buffer.data);
+	if (buffer->product.data)
+		vfree(buffer->product.data);
+
+	memset(buffer, 0, sizeof(struct diag_trace_buffer));
+}
+
+void discard_diag_trace_buffer(struct diag_trace_buffer *buffer)
+{
+	unsigned long flags;
+
+	diag_trace_buffer_mutex_lock(buffer);
+	diag_trace_buffer_spin_lock(buffer, flags);
+	buffer->buffer.circle = buffer->buffer.pos = buffer->buffer.tail = 0;
+	diag_trace_buffer_spin_unlock(buffer, flags);
+	diag_trace_buffer_mutex_unlock(buffer);
+}
+
+void backup_diag_trace_buffer(struct diag_trace_buffer *buffer)
+{
+	unsigned long flags;
+
+	if (!buffer->buffer.data || !buffer->product.data)
+		return;
+
+	diag_trace_buffer_mutex_lock(buffer);
+	diag_trace_buffer_spin_lock(buffer, flags);
+
+	buffer->product.len = 0;
+	if (buffer->buffer.pos < buffer->buf_size) {
+		if (buffer->buffer.circle) {
+			int tail_len = 0;
+			if (buffer->buffer.tail > buffer->buffer.pos) {
+				tail_len = buffer->buffer.tail - buffer->buffer.pos;
+
+				memcpy(buffer->product.data,
+					buffer->buffer.data + buffer->buffer.pos,
+					tail_len);
+			}
+			memcpy(buffer->product.data + tail_len,
+				buffer->buffer.data,
+				buffer->buffer.pos);
+			buffer->product.len = buffer->buffer.pos + tail_len;
+		} else {
+			memcpy(buffer->product.data, buffer->buffer.data, buffer->buffer.pos);
+			buffer->product.len = buffer->buffer.pos;
+		}
+	}
+
+	buffer->buffer.circle = buffer->buffer.pos = buffer->buffer.tail = 0;
+
+	diag_trace_buffer_spin_unlock(buffer, flags);
+	diag_trace_buffer_mutex_unlock(buffer);
+}
+
+asmlinkage int
+diag_trace_buffer_write_nolock(struct diag_trace_buffer *buffer,
+	const void *data, size_t len)
+{
+	unsigned int left;
+
+	left = buffer->buf_size - buffer->buffer.pos;
+	if (len < left) {
+		memcpy(buffer->buffer.data + buffer->buffer.pos,
+			data, len);
+		buffer->buffer.pos += len;
+	} else {
+		buffer->buffer.tail = buffer->buffer.pos;
+		memcpy(buffer->buffer.data, data, len);
+		buffer->buffer.pos = len;
+		buffer->buffer.circle = 1;
+	}
+
+	return len;
+}
+
+asmlinkage int
+diag_trace_buffer_write(struct diag_trace_buffer *buffer,
+	const void *data, size_t len)
+{
+	int ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(&buffer->buffer.lock, flags);
+	ret = diag_trace_buffer_write_nolock(buffer, data, len);
+	spin_unlock_irqrestore(&buffer->buffer.lock, flags);
+
+	return ret;
+}
+
+static asmlinkage int
+__diag_trace_buffer_printk_nolock(struct diag_trace_buffer *buffer,
+	const char *fmt, va_list ap)
+{
+	unsigned int len = 0;
+	unsigned int left;
+
+	len = vsnprintf(buffer->fmt_buffer, DIAG_TRACE_BUF_SIZE, fmt, ap);
+	if (len > DIAG_TRACE_BUF_SIZE)
+		return len;
+
+	left = buffer->buf_size - buffer->buffer.pos;
+	if (len < left) {
+		memcpy(buffer->buffer.data + buffer->buffer.pos,
+			buffer->fmt_buffer, len);
+		buffer->buffer.pos += len;
+	} else {
+		buffer->buffer.tail = buffer->buffer.pos;
+		memcpy(buffer->buffer.data, buffer->fmt_buffer, len);
+		buffer->buffer.pos = len;
+		buffer->buffer.circle = 1;
+	}
+
+	return len;
+}
+
+asmlinkage int
+diag_trace_buffer_printk_nolock(struct diag_trace_buffer *buffer,
+	const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+	
+	va_start(ap, fmt);
+	ret = __diag_trace_buffer_printk_nolock(buffer, fmt, ap);
+	va_end(ap);
+	
+	return ret;
+}
+
+asmlinkage int
+diag_trace_buffer_printk(struct diag_trace_buffer *buffer,
+	const char *fmt, ...)
+{
+	int ret;
+	unsigned long flags;
+	va_list ap;
+	
+	spin_lock_irqsave(&buffer->buffer.lock, flags);
+	va_start(ap, fmt);
+	ret = __diag_trace_buffer_printk_nolock(buffer, fmt, ap);
+	va_end(ap);
+	spin_unlock_irqrestore(&buffer->buffer.lock, flags);
+
+	return ret;
+}
+
+void diag_trace_buffer_mutex_lock(struct diag_trace_buffer *buffer)
+{
+	mutex_lock(&buffer->buffer.mutex);
+}
+
+void diag_trace_buffer_mutex_unlock(struct diag_trace_buffer *buffer)
+{
+	mutex_unlock(&buffer->buffer.mutex);
+}
+