[for-linus][PATCH 1/5] bootconfig: Allocate xbc_nodes array dynamically

From: Steven Rostedt
Date: Tue Feb 11 2020 - 08:50:13 EST


From: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

To reduce the large static array from kernel data, allocate
xbc_nodes array dynamically only if the kernel loads a
bootconfig.

Note that this also add dummy memblock.h for user-spacae
bootconfig tool.

Link: http://lkml.kernel.org/r/158108569699.3187.6512834527603883707.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
lib/bootconfig.c | 15 ++++++++++++---
tools/bootconfig/include/linux/memblock.h | 12 ++++++++++++
2 files changed, 24 insertions(+), 3 deletions(-)
create mode 100644 tools/bootconfig/include/linux/memblock.h

diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index afb2e767e6fe..3ea601a2eba5 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -6,12 +6,13 @@

#define pr_fmt(fmt) "bootconfig: " fmt

+#include <linux/bootconfig.h>
#include <linux/bug.h>
#include <linux/ctype.h>
#include <linux/errno.h>
#include <linux/kernel.h>
+#include <linux/memblock.h>
#include <linux/printk.h>
-#include <linux/bootconfig.h>
#include <linux/string.h>

/*
@@ -23,7 +24,7 @@
* node (for array).
*/

-static struct xbc_node xbc_nodes[XBC_NODE_MAX] __initdata;
+static struct xbc_node *xbc_nodes __initdata;
static int xbc_node_num __initdata;
static char *xbc_data __initdata;
static size_t xbc_data_size __initdata;
@@ -719,7 +720,8 @@ void __init xbc_destroy_all(void)
xbc_data = NULL;
xbc_data_size = 0;
xbc_node_num = 0;
- memset(xbc_nodes, 0, sizeof(xbc_nodes));
+ memblock_free(__pa(xbc_nodes), sizeof(struct xbc_node) * XBC_NODE_MAX);
+ xbc_nodes = NULL;
}

/**
@@ -748,6 +750,13 @@ int __init xbc_init(char *buf)
return -ERANGE;
}

+ xbc_nodes = memblock_alloc(sizeof(struct xbc_node) * XBC_NODE_MAX,
+ SMP_CACHE_BYTES);
+ if (!xbc_nodes) {
+ pr_err("Failed to allocate memory for bootconfig nodes.\n");
+ return -ENOMEM;
+ }
+ memset(xbc_nodes, 0, sizeof(struct xbc_node) * XBC_NODE_MAX);
xbc_data = buf;
xbc_data_size = ret + 1;
last_parent = NULL;
diff --git a/tools/bootconfig/include/linux/memblock.h b/tools/bootconfig/include/linux/memblock.h
new file mode 100644
index 000000000000..7862f217d85d
--- /dev/null
+++ b/tools/bootconfig/include/linux/memblock.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _XBC_LINUX_MEMBLOCK_H
+#define _XBC_LINUX_MEMBLOCK_H
+
+#include <stdlib.h>
+
+#define __pa(addr) (addr)
+#define SMP_CACHE_BYTES 0
+#define memblock_alloc(size, align) malloc(size)
+#define memblock_free(paddr, size) free(paddr)
+
+#endif
--
2.24.1