meminfo: Show reliable memory info

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4PM01
CVE: NA

--------------------------------

Add ReliMemTotal & ReliMemUsed in /proc/meminfo to show memory info about
reliable memory.

- ReliableTotal: total reliable RAM

- ReliableUsed: thei used amount of reliable memory kernel
Signed-off-by: NMa Wupeng <mawupeng1@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

Documentation/filesystems/proc.rst

@@ -963,6 +963,8 @@ varies by architecture and compile options.  The following is from a
     AnonHugePages:   49152 kB
     ShmemHugePages:      0 kB
     ShmemPmdMapped:      0 kB
+    ReliableTotal: 7340032 kB
+    ReliableUsed:   418824 kB
 
 MemTotal
               Total usable RAM (i.e. physical RAM minus a few reserved
@@ -1092,6 +1094,10 @@ VmallocChunk
 Percpu
               Memory allocated to the percpu allocator used to back percpu
               allocations. This stat excludes the cost of metadata.
+ReliableTotal
+              Total reliable memory size
+ReliableUsed
+              The used amount of reliable memory
 
 vmallocinfo
 ~~~~~~~~~~~

fs/proc/meminfo.c

@@ -150,6 +150,8 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 
 	arch_report_meminfo(m);
 
+	reliable_report_meminfo(m);
+
 	return 0;
 }
 

include/linux/mem_reliable.h

@@ -17,6 +17,7 @@ extern bool reliable_enabled;
 extern void add_reliable_mem_size(long sz);
 extern void mem_reliable_init(bool has_unmirrored_mem,
 			      unsigned long *zone_movable_pfn);
+extern void reliable_report_meminfo(struct seq_file *m);
 
 static inline bool mem_reliable_is_enabled(void)
 {
@@ -57,6 +58,7 @@ static inline bool skip_none_movable_zone(gfp_t gfp, struct zoneref *z)
 {
 	return false;
 }
+static inline void reliable_report_meminfo(struct seq_file *m) {}
 #endif
 
 #endif

mm/mem_reliable.c

@@ -5,6 +5,8 @@
 #include <linux/mm.h>
 #include <linux/memory.h>
 #include <linux/memory_hotplug.h>
+#include <linux/seq_file.h>
+#include <linux/mmzone.h>
 
 DEFINE_STATIC_KEY_FALSE(mem_reliable);
 
@@ -22,6 +24,18 @@ static unsigned long total_reliable_mem_sz(void)
 	return atomic_long_read(&total_reliable_mem);
 }
 
+static unsigned long used_reliable_mem_sz(void)
+{
+	unsigned long nr_page = 0;
+	struct zone *z;
+
+	for_each_populated_zone(z)
+		if (zone_idx(z) < ZONE_MOVABLE)
+			nr_page += zone_page_state(z, NR_FREE_PAGES);
+
+	return total_reliable_mem_sz() - nr_page * PAGE_SIZE;
+}
+
 static int reliable_mem_notifier(struct notifier_block *nb,
 				 unsigned long action, void *arg)
 {
@@ -77,3 +91,14 @@ void mem_reliable_init(bool has_unmirrored_mem, unsigned long *zone_movable_pfn)
 	pr_info("init succeed, mirrored memory size(%lu)\n",
 		total_reliable_mem_sz());
 }
+
+void reliable_report_meminfo(struct seq_file *m)
+{
+	if (!mem_reliable_is_enabled())
+		return;
+
+	seq_printf(m, "ReliableTotal:    %8lu kB\n",
+		   total_reliable_mem_sz() >> 10);
+	seq_printf(m, "ReliableUsed:     %8lu kB\n",
+		   used_reliable_mem_sz() >> 10);
+}