[GIT PULL] tracing: Minor fixes to the bootconfig processing

From: Steven Rostedt
Date: Fri Sep 10 2021 - 19:13:32 EST



Linus,

Minor fixes to the processing of the bootconfig tree.


Please pull the latest trace-v5.15-3 tree, which can be found at:


git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
trace-v5.15-3

Tag SHA1: 38cd35cdd85430a99c001ef2bbf9077f125b07db
Head SHA1: 5dfe50b05588010f347cb2f436434bf22b7a84ed


Masami Hiramatsu (3):
tracing/boot: Fix trace_boot_hist_add_array() to check array is value
tracing/boot: Fix to check the histogram control param is a leaf node
bootconfig: Rename xbc_node_find_child() to xbc_node_find_subkey()

----
include/linux/bootconfig.h | 4 ++--
kernel/trace/trace_boot.c | 37 ++++++++++++++++++-------------------
lib/bootconfig.c | 8 ++++----
3 files changed, 24 insertions(+), 25 deletions(-)
---------------------------
diff --git a/include/linux/bootconfig.h b/include/linux/bootconfig.h
index abe089c27529..537e1b991f11 100644
--- a/include/linux/bootconfig.h
+++ b/include/linux/bootconfig.h
@@ -110,7 +110,7 @@ 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 +148,7 @@ 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);
}

/**
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index 388e65d05978..8d252f63cd78 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -219,13 +219,12 @@ static int __init
trace_boot_hist_add_array(struct xbc_node *hnode, char **bufp,
char *end, const char *key)
{
- struct xbc_node *knode, *anode;
+ struct xbc_node *anode;
const char *p;
char sep;

- knode = xbc_node_find_child(hnode, key);
- if (knode) {
- anode = xbc_node_get_child(knode);
+ p = xbc_node_find_value(hnode, key, &anode);
+ if (p) {
if (!anode) {
pr_err("hist.%s requires value(s).\n", key);
return -EINVAL;
@@ -263,9 +262,9 @@ trace_boot_hist_add_one_handler(struct xbc_node *hnode, char **bufp,
append_printf(bufp, end, ":%s(%s)", handler, p);

/* Compose 'action' parameter */
- knode = xbc_node_find_child(hnode, "trace");
+ knode = xbc_node_find_subkey(hnode, "trace");
if (!knode)
- knode = xbc_node_find_child(hnode, "save");
+ knode = xbc_node_find_subkey(hnode, "save");

if (knode) {
anode = xbc_node_get_child(knode);
@@ -284,7 +283,7 @@ trace_boot_hist_add_one_handler(struct xbc_node *hnode, char **bufp,
sep = ',';
}
append_printf(bufp, end, ")");
- } else if (xbc_node_find_child(hnode, "snapshot")) {
+ } else if (xbc_node_find_subkey(hnode, "snapshot")) {
append_printf(bufp, end, ".snapshot()");
} else {
pr_err("hist.%s requires an action.\n",
@@ -315,7 +314,7 @@ trace_boot_hist_add_handlers(struct xbc_node *hnode, char **bufp,
break;
}

- if (xbc_node_find_child(hnode, param))
+ if (xbc_node_find_subkey(hnode, param))
ret = trace_boot_hist_add_one_handler(hnode, bufp, end, handler, param);

return ret;
@@ -375,7 +374,7 @@ trace_boot_compose_hist_cmd(struct xbc_node *hnode, char *buf, size_t size)
if (p)
append_printf(&buf, end, ":name=%s", p);

- node = xbc_node_find_child(hnode, "var");
+ node = xbc_node_find_subkey(hnode, "var");
if (node) {
xbc_node_for_each_key_value(node, knode, p) {
/* Expression must not include spaces. */
@@ -386,21 +385,21 @@ trace_boot_compose_hist_cmd(struct xbc_node *hnode, char *buf, size_t size)
}

/* Histogram control attributes (mutual exclusive) */
- if (xbc_node_find_child(hnode, "pause"))
+ if (xbc_node_find_value(hnode, "pause", NULL))
append_printf(&buf, end, ":pause");
- else if (xbc_node_find_child(hnode, "continue"))
+ else if (xbc_node_find_value(hnode, "continue", NULL))
append_printf(&buf, end, ":continue");
- else if (xbc_node_find_child(hnode, "clear"))
+ else if (xbc_node_find_value(hnode, "clear", NULL))
append_printf(&buf, end, ":clear");

/* Histogram handler and actions */
- node = xbc_node_find_child(hnode, "onmax");
+ node = xbc_node_find_subkey(hnode, "onmax");
if (node && trace_boot_hist_add_handlers(node, &buf, end, "var") < 0)
return -EINVAL;
- node = xbc_node_find_child(hnode, "onchange");
+ node = xbc_node_find_subkey(hnode, "onchange");
if (node && trace_boot_hist_add_handlers(node, &buf, end, "var") < 0)
return -EINVAL;
- node = xbc_node_find_child(hnode, "onmatch");
+ node = xbc_node_find_subkey(hnode, "onmatch");
if (node && trace_boot_hist_add_handlers(node, &buf, end, "event") < 0)
return -EINVAL;

@@ -437,7 +436,7 @@ trace_boot_init_histograms(struct trace_event_file *file,
}
}

- if (xbc_node_find_child(hnode, "keys")) {
+ if (xbc_node_find_subkey(hnode, "keys")) {
if (trace_boot_compose_hist_cmd(hnode, buf, size) == 0) {
tmp = kstrdup(buf, GFP_KERNEL);
if (trigger_process_regex(file, buf) < 0)
@@ -496,7 +495,7 @@ trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode,
else if (trigger_process_regex(file, buf) < 0)
pr_err("Failed to apply an action: %s\n", p);
}
- anode = xbc_node_find_child(enode, "hist");
+ anode = xbc_node_find_subkey(enode, "hist");
if (anode)
trace_boot_init_histograms(file, anode, buf, ARRAY_SIZE(buf));
} else if (xbc_node_find_value(enode, "actions", NULL))
@@ -518,7 +517,7 @@ trace_boot_init_events(struct trace_array *tr, struct xbc_node *node)
bool enable, enable_all = false;
const char *data;

- node = xbc_node_find_child(node, "event");
+ node = xbc_node_find_subkey(node, "event");
if (!node)
return;
/* per-event key starts with "event.GROUP.EVENT" */
@@ -621,7 +620,7 @@ trace_boot_init_instances(struct xbc_node *node)
struct trace_array *tr;
const char *p;

- node = xbc_node_find_child(node, "instance");
+ node = xbc_node_find_subkey(node, "instance");
if (!node)
return;

diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 927017431fb6..f8419cff1147 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -142,16 +142,16 @@ xbc_node_match_prefix(struct xbc_node *node, const char **prefix)
}

/**
- * xbc_node_find_child() - Find a child node which matches given key
+ * xbc_node_find_subkey() - Find a subkey node which matches given key
* @parent: An XBC node.
* @key: A key string.
*
- * Search a node under @parent which matches @key. The @key can contain
+ * Search a key node under @parent which matches @key. The @key can contain
* several words jointed with '.'. If @parent is NULL, this searches the
* node from whole tree. Return NULL if no node is matched.
*/
struct xbc_node * __init
-xbc_node_find_child(struct xbc_node *parent, const char *key)
+xbc_node_find_subkey(struct xbc_node *parent, const char *key)
{
struct xbc_node *node;

@@ -191,7 +191,7 @@ const char * __init
xbc_node_find_value(struct xbc_node *parent, const char *key,
struct xbc_node **vnode)
{
- struct xbc_node *node = xbc_node_find_child(parent, key);
+ struct xbc_node *node = xbc_node_find_subkey(parent, key);

if (!node || !xbc_node_is_key(node))
return NULL;