KYLIN: osinfo: Add /proc/osinfo interface

Mainline: NA
From: NA
Category: Feature
CVE: NA

内核新增 /proc/osinfo 接口，主要目的是为了方便在特定的情况下
进行内核的信息收集，方便后端开发者快速定位潜在的问题。

Cc: nh <nh@tj.kylinos.cn> #linux-hwe-5.15
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Change-Id: Icf07252a70c76ca0883e001667c8bfc0707ecb62
Signed-off-by: chen zhang <chenzhang@kylinos.cn>
Reviewed-on: http://gerrit.kylin.com/c/kfocal/+/23609

Makefile

@@ -359,6 +359,8 @@ include $(srctree)/scripts/Kbuild.include
 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
+SOURCEVERSION = $(shell git rev-parse HEAD 2> /dev/null)
+
 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 
 include $(srctree)/scripts/subarch.include
@@ -1248,7 +1250,8 @@ define filechk_utsrelease.h
 	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
 	  exit 1;                                                         \
 	fi;                                                               \
-	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
+	(echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";		\
+	echo \#define SOURCE_VERSION \"$(SOURCEVERSION)\";)
 endef
 
 define filechk_version.h

fs/proc/Makefile

@@ -11,6 +11,9 @@ proc-$(CONFIG_MMU)	:= task_mmu.o
 
 proc-y       += inode.o root.o base.o generic.o array.o \
 		fd.o
+
+$(obj)/osinfo.o: include/generated/compile.h
+
 proc-$(CONFIG_TTY)      += proc_tty.o
 proc-y	+= cmdline.o
 proc-y	+= consoles.o
@@ -19,6 +22,7 @@ proc-y	+= devices.o
 proc-y	+= interrupts.o
 proc-y	+= loadavg.o
 proc-y	+= meminfo.o
+proc-y	+= osinfo.o
 proc-y	+= stat.o
 proc-y	+= uptime.o
 proc-y	+= util.o
@@ -34,3 +38,17 @@ proc-$(CONFIG_PROC_VMCORE)	+= vmcore.o
 proc-$(CONFIG_PRINTK)	+= kmsg.o
 proc-$(CONFIG_PROC_PAGE_MONITOR)	+= page.o
 proc-$(CONFIG_BOOT_CONFIG)	+= bootconfig.o
+
+# compile.h changes depending on hostname, generation number, etc,
+# so we regenerate it always.
+# mkcompile_h will make sure to only update the
+# actual file if its content has changed.
+
+       chk_compile.h = :
+ quiet_chk_compile.h = echo '  CHK     $@'
+silent_chk_compile.h = :
+include/generated/compile.h: FORCE
+	@$($(quiet)chk_compile.h)
+	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkcompile_h $@   \
+	"$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)"    \
+	"$(CONFIG_PREEMPT_RT)" "$(CC) $(KBUILD_CFLAGS)"

fs/proc/osinfo.c

@@ -0,0 +1,72 @@
+/*
+ * fs/proc/osinfo.c
+ *
+ * Authors: Jackie Liu <liuyun01@kylinos.cn>
+ * Copyright (C) 2020, KylinSoft Co., Ltd.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/cpumask.h>
+#include <linux/mm.h>
+#include <generated/utsrelease.h>
+#include <generated/compile.h>
+
+static int osinfo_proc_show(struct seq_file *m, void *v)
+{
+	struct sysinfo i;
+	struct timespec64 uptime;
+
+	si_meminfo(&i);
+	ktime_get_boottime_ts64(&uptime);
+
+	seq_printf(m, "Kernel Version:\t\t%s\n", UTS_RELEASE);
+	seq_printf(m, "Source Version:\t\t%s\n",
+		   strlen(SOURCE_VERSION) ? SOURCE_VERSION : "Unknown");
+	seq_printf(m, "Build Time:\t\t%s\n", UTS_VERSION);
+	seq_printf(m, "Architecture:\t\t%s\n", UTS_MACHINE);
+	seq_printf(m, "Online CPUs:\t\t%d\n", num_online_cpus());
+	seq_printf(m, "MemTotal:\t\t%ld KB\n"
+		      "PageSize:\t\t%ld KB\n", i.totalram << (PAGE_SHIFT - 10),
+		      PAGE_SIZE >> 10);
+	seq_printf(m, "Uptime:\t\t\t%lu.%02lu Sec\n", (unsigned long) uptime.tv_sec,
+		      (uptime.tv_nsec / (NSEC_PER_SEC / 100)));
+	seq_printf(m, "Cmdline:\t\t%s\n", saved_command_line);
+
+	return 0;
+}
+
+static int osinfo_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, osinfo_proc_show, NULL);
+}
+
+static const struct proc_ops osinfo_proc_ops = {
+	.proc_open	= osinfo_proc_open,
+	.proc_read	= seq_read,
+	.proc_lseek	= seq_lseek,
+	.proc_release	= single_release,
+};
+
+static int __init proc_osinfo_init(void)
+{
+	proc_create("osinfo", 0, NULL, &osinfo_proc_ops);
+	return 0;
+}
+fs_initcall(proc_osinfo_init);