ctrliq
diff --git a/‎Documentation/admin-guide/bootconfig.rst‎
Lines changed: 70 additions & 4 deletions b/‎Documentation/admin-guide/bootconfig.rst‎
Lines changed: 70 additions & 4 deletions
diff --git a/‎Documentation/trace/boottime-trace.rst‎
Lines changed: 78 additions & 5 deletions b/‎Documentation/trace/boottime-trace.rst‎
Lines changed: 78 additions & 5 deletions
diff --git a/‎MAINTAINERS‎
Lines changed: 1 addition & 0 deletions b/‎MAINTAINERS‎
Lines changed: 1 addition & 0 deletions
diff --git a/‎include/linux/bootconfig.h‎
Lines changed: 37 additions & 13 deletions b/‎include/linux/bootconfig.h‎
Lines changed: 37 additions & 13 deletions
diff --git a/‎init/Kconfig‎
Lines changed: 33 additions & 1 deletion b/‎init/Kconfig‎
Lines changed: 33 additions & 1 deletion
@@ -158,9 +158,15 @@ Each key-value pair is shown in each line with following style::
 Boot Kernel With a Boot Config
 ==============================
 
-Since the boot configuration file is loaded with initrd, it will be added
-to the end of the initrd (initramfs) image file with padding, size,
-checksum and 12-byte magic word as below.
+There are two options to boot the kernel with bootconfig: attaching the
+bootconfig to the initrd image or embedding it in the kernel itself.
+
+Attaching a Boot Config to Initrd
+---------------------------------
+
+Since the boot configuration file is loaded with initrd by default,
+it will be added to the end of the initrd (initramfs) image file with
+padding, size, checksum and 12-byte magic word as below.
 
 [initrd][bootconfig][padding][size(le32)][checksum(le32)][#BOOTCONFIG\n]
 
@@ -178,7 +184,7 @@ update the boot loader and the kernel image itself as long as the boot
 loader passes the correct initrd file size. If by any chance, the boot
 loader passes a longer size, the kernel fails to find the bootconfig data.
 
-To do this operation, Linux kernel provides "bootconfig" command under
+To do this operation, Linux kernel provides ``bootconfig`` command under
 tools/bootconfig, which allows admin to apply or delete the config file
 to/from initrd image. You can build it by the following command::
 
@@ -195,6 +201,66 @@ To remove the config from the image, you can use -d option as below::
 
 Then add "bootconfig" on the normal kernel command line to tell the
 kernel to look for the bootconfig at the end of the initrd file.
+Alternatively, build your kernel with the ``CONFIG_BOOT_CONFIG_FORCE``
+Kconfig option selected.
+
+Embedding a Boot Config into Kernel
+-----------------------------------
+
+If you can not use initrd, you can also embed the bootconfig file in the
+kernel by Kconfig options. In this case, you need to recompile the kernel
+with the following configs::
+
+ CONFIG_BOOT_CONFIG_EMBED=y
+ CONFIG_BOOT_CONFIG_EMBED_FILE="/PATH/TO/BOOTCONFIG/FILE"
+
+``CONFIG_BOOT_CONFIG_EMBED_FILE`` requires an absolute path or a relative
+path to the bootconfig file from source tree or object tree.
+The kernel will embed it as the default bootconfig.
+
+Just as when attaching the bootconfig to the initrd, you need ``bootconfig``
+option on the kernel command line to enable the embedded bootconfig, or,
+alternatively, build your kernel with the ``CONFIG_BOOT_CONFIG_FORCE``
+Kconfig option selected.
+
+Note that even if you set this option, you can override the embedded
+bootconfig by another bootconfig which attached to the initrd.
+
+Kernel parameters via Boot Config
+=================================
+
+In addition to the kernel command line, the boot config can be used for
+passing the kernel parameters. All the key-value pairs under ``kernel``
+key will be passed to kernel cmdline directly. Moreover, the key-value
+pairs under ``init`` will be passed to init process via the cmdline.
+The parameters are concatenated with user-given kernel cmdline string
+as the following order, so that the command line parameter can override
+bootconfig parameters (this depends on how the subsystem handles parameters
+but in general, earlier parameter will be overwritten by later one.)::
+
+ [bootconfig params][cmdline params] -- [bootconfig init params][cmdline init params]
+
+Here is an example of the bootconfig file for kernel/init parameters.::
+
+ kernel {
+   root = 01234567-89ab-cdef-0123-456789abcd
+ }
+ init {
+  splash
+ }
+
+This will be copied into the kernel cmdline string as the following::
+
+ root="01234567-89ab-cdef-0123-456789abcd" -- splash
+
+If user gives some other command line like,::
+
+ ro bootconfig -- quiet
+
+The final kernel cmdline will be the following::
+
+ root="01234567-89ab-cdef-0123-456789abcd" ro bootconfig -- splash quiet
+
 
 Config File Limitation
 ======================
 
@@ -125,6 +125,69 @@ Note that kprobe and synthetic event definitions can be written under
 instance node, but those are also visible from other instances. So please
 take care for event name conflict.
 
+Ftrace Histogram Options
+------------------------
+
+Since it is too long to write a histogram action as a string for per-event
+action option, there are tree-style options under per-event 'hist' subkey
+for the histogram actions. For the detail of the each parameter,
+please read the event histogram document (Documentation/trace/histogram.rst)
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]keys = KEY1[, KEY2[...]]
+  Set histogram key parameters. (Mandatory)
+  The 'N' is a digit string for the multiple histogram. You can omit it
+  if there is one histogram on the event.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]values = VAL1[, VAL2[...]]
+  Set histogram value parameters.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]sort = SORT1[, SORT2[...]]
+  Set histogram sort parameter options.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]size = NR_ENTRIES
+  Set histogram size (number of entries).
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]name = NAME
+  Set histogram name.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]var.VARIABLE = EXPR
+  Define a new VARIABLE by EXPR expression.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<pause|continue|clear>
+  Set histogram control parameter. You can set one of them.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmatch.[M.]event = GROUP.EVENT
+  Set histogram 'onmatch' handler matching event parameter.
+  The 'M' is a digit string for the multiple 'onmatch' handler. You can omit it
+  if there is one 'onmatch' handler on this histogram.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmatch.[M.]trace = EVENT[, ARG1[...]]
+  Set histogram 'trace' action for 'onmatch'.
+  EVENT must be a synthetic event name, and ARG1... are parameters
+  for that event. Mandatory if 'onmatch.event' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmax.[M.]var = VAR
+  Set histogram 'onmax' handler variable parameter.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onchange.[M.]var = VAR
+  Set histogram 'onchange' handler variable parameter.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<onmax|onchange>.[M.]save = ARG1[, ARG2[...]]
+  Set histogram 'save' action parameters for 'onmax' or 'onchange' handler.
+  This option or below 'snapshot' option is mandatory if 'onmax.var' or
+  'onchange.var' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<onmax|onchange>.[M.]snapshot
+  Set histogram 'snapshot' action for 'onmax' or 'onchange' handler.
+  This option or above 'save' option is mandatory if 'onmax.var' or
+  'onchange.var' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.filter = FILTER_EXPR
+  Set histogram filter expression. You don't need 'if' in the FILTER_EXPR.
+
+Note that this 'hist' option can conflict with the per-event 'actions'
+option if the 'actions' option has a histogram action.
+
 
 When to Start
 =============
@@ -159,13 +222,23 @@ below::
         }
         synthetic.initcall_latency {
                 fields = "unsigned long func", "u64 lat"
-                actions = "hist:keys=func.sym,lat:vals=lat:sort=lat"
+                hist {
+                        keys = func.sym, lat
+                        values = lat
+                        sort = lat
+                }
         }
-        initcall.initcall_start {
-                actions = "hist:keys=func:ts0=common_timestamp.usecs"
+        initcall.initcall_start.hist {
+                keys = func
+                var.ts0 = common_timestamp.usecs
         }
-        initcall.initcall_finish {
-                actions = "hist:keys=func:lat=common_timestamp.usecs-$ts0:onmatch(initcall.initcall_start).initcall_latency(func,$lat)"
+        initcall.initcall_finish.hist {
+                keys = func
+                var.lat = common_timestamp.usecs - $ts0
+                onmatch {
+                        event = initcall.initcall_start
+                        trace = initcall_latency, func, $lat
+                }
         }
   }
 
 
@@ -7238,6 +7238,7 @@ S:	Maintained
 F:	Documentation/admin-guide/bootconfig.rst
 F:	fs/proc/bootconfig.c
 F:	include/linux/bootconfig.h
+F:	lib/bootconfig-data.S
 F:	lib/bootconfig.c
 F:	tools/bootconfig/*
 F:	tools/bootconfig/scripts/*
 
@@ -7,8 +7,18 @@
  * Author: Masami Hiramatsu <mhiramat@kernel.org>
  */
 
+#ifdef __KERNEL__
 #include <linux/kernel.h>
 #include <linux/types.h>
+#else /* !__KERNEL__ */
+/*
+ * NOTE: This is only for tools/bootconfig, because tools/bootconfig will
+ * run the parser sanity test.
+ * This does NOT mean linux/bootconfig.h is available in the user space.
+ * However, if you change this file, please make sure the tools/bootconfig
+ * has no issue on building and running.
+ */
+#endif
 
 #define BOOTCONFIG_MAGIC	"#BOOTCONFIG\n"
 #define BOOTCONFIG_MAGIC_LEN	12
@@ -25,10 +35,10 @@
  * The checksum will be used with the BOOTCONFIG_MAGIC and the size for
  * embedding the bootconfig in the initrd image.
  */
-static inline __init u32 xbc_calc_checksum(void *data, u32 size)
+static inline __init uint32_t xbc_calc_checksum(void *data, uint32_t size)
 {
 	unsigned char *p = data;
-	u32 ret = 0;
+	uint32_t ret = 0;
 
 	while (size--)
 		ret += *p++;
@@ -38,18 +48,18 @@ static inline __init u32 xbc_calc_checksum(void *data, u32 size)
 
 /* XBC tree node */
 struct xbc_node {
-	u16 next;
-	u16 child;
-	u16 parent;
-	u16 data;
+	uint16_t next;
+	uint16_t child;
+	uint16_t parent;
+	uint16_t data;
 } __attribute__ ((__packed__));
 
 #define XBC_KEY		0
 #define XBC_VALUE	(1 << 15)
 /* Maximum size of boot config is 32KB - 1 */
 #define XBC_DATA_MAX	(XBC_VALUE - 1)
 
-#define XBC_NODE_MAX	1024
+#define XBC_NODE_MAX	8192
 #define XBC_KEYLEN_MAX	256
 #define XBC_DEPTH_MAX	16
 
@@ -110,7 +120,7 @@ static inline __init bool xbc_node_is_leaf(struct xbc_node *node)
 }
 
 /* Tree-based key-value access APIs */
-struct xbc_node * __init xbc_node_find_child(struct xbc_node *parent,
+struct xbc_node * __init xbc_node_find_subkey(struct xbc_node *parent,
 					     const char *key);
 
 const char * __init xbc_node_find_value(struct xbc_node *parent,
@@ -148,7 +158,7 @@ xbc_find_value(const char *key, struct xbc_node **vnode)
  */
 static inline struct xbc_node * __init xbc_find_node(const char *key)
 {
-	return xbc_node_find_child(NULL, key);
+	return xbc_node_find_subkey(NULL, key);
 }
 
 /**
@@ -271,13 +281,27 @@ static inline int __init xbc_node_compose_key(struct xbc_node *node,
 }
 
 /* XBC node initializer */
-int __init xbc_init(char *buf, const char **emsg, int *epos);
+int __init xbc_init(const char *buf, size_t size, const char **emsg, int *epos);
 
+/* XBC node and size information */
+int __init xbc_get_info(int *node_size, size_t *data_size);
 
 /* XBC cleanup data structures */
-void __init xbc_destroy_all(void);
+void __init _xbc_exit(bool early);
 
-/* Debug dump functions */
-void __init xbc_debug_dump(void);
+static inline void xbc_exit(void)
+{
+	_xbc_exit(false);
+}
+
+/* XBC embedded bootconfig data in kernel */
+#ifdef CONFIG_BOOT_CONFIG_EMBED
+const char * __init xbc_get_embedded_bootconfig(size_t *size);
+#else
+static inline const char *xbc_get_embedded_bootconfig(size_t *size)
+{
+	return NULL;
+}
+#endif
 
 #endif
@@ -1323,7 +1323,7 @@ endif
 
 config BOOT_CONFIG
 	bool "Boot config support"
-	select BLK_DEV_INITRD
+	select BLK_DEV_INITRD if !BOOT_CONFIG_EMBED
 	help
 	  Extra boot config allows system admin to pass a config file as
 	  complemental extension of kernel cmdline when booting.
@@ -1333,6 +1333,38 @@ config BOOT_CONFIG
 
 	  If unsure, say Y.
 
+config BOOT_CONFIG_FORCE
+	bool "Force unconditional bootconfig processing"
+	depends on BOOT_CONFIG
+	default y if BOOT_CONFIG_EMBED
+	help
+	  With this Kconfig option set, BOOT_CONFIG processing is carried
+	  out even when the "bootconfig" kernel-boot parameter is omitted.
+	  In fact, with this Kconfig option set, there is no way to
+	  make the kernel ignore the BOOT_CONFIG-supplied kernel-boot
+	  parameters.
+
+	  If unsure, say N.
+
+config BOOT_CONFIG_EMBED
+	bool "Embed bootconfig file in the kernel"
+	depends on BOOT_CONFIG
+	help
+	  Embed a bootconfig file given by BOOT_CONFIG_EMBED_FILE in the
+	  kernel. Usually, the bootconfig file is loaded with the initrd
+	  image. But if the system doesn't support initrd, this option will
+	  help you by embedding a bootconfig file while building the kernel.
+
+	  If unsure, say N.
+
+config BOOT_CONFIG_EMBED_FILE
+	string "Embedded bootconfig file path"
+	depends on BOOT_CONFIG_EMBED
+	help
+	  Specify a bootconfig file which will be embedded to the kernel.
+	  This bootconfig will be used if there is no initrd or no other
+	  bootconfig in the initrd.
+
 choice
 	prompt "Compiler optimization level"
 	default CC_OPTIMIZE_FOR_PERFORMANCE