[03/54] tracing: Add hist_field_name() accessor

Commit Message

[e-mail] Aug. 29, 2018, 12:17 p.m. UTC

In preparation for hist_fields that won't be strictly based on
trace_event_fields, add a new hist_field_name() accessor to allow that
flexibility and update associated users.

Link: http://lkml.kernel.org/r/5b5[e-mail]

Signed-off-by: Tom Zanussi <[e-mail]>
Signed-off-by: Steven Rostedt (VMware) <[e-mail]>
(cherry picked from commit 85013256cf01629f72a327674c5d007b4a4b40da)
Signed-off-by: Hirotaka MOTAI <[e-mail]>
---
 kernel/trace/trace_events_hist.c | 67 +++++++++++++++++++++-----------
 1 file changed, 45 insertions(+), 22 deletions(-)

Patch

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 0c7ec304..34edf5fd 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -141,16 +141,33 @@  struct hist_trigger_data {
 	unsigned int			key_size;
 	struct tracing_map_sort_key	sort_keys[TRACING_MAP_SORT_KEYS_MAX];
 	unsigned int			n_sort_keys;
 	struct trace_event_file		*event_file;
 	struct hist_trigger_attrs	*attrs;
 	struct tracing_map		*map;
 };
 
+static const char *hist_field_name(struct hist_field *field,
+				   unsigned int level)
+{
+	const char *field_name = "";
+
+	if (level > 1)
+		return field_name;
+
+	if (field->field)
+		field_name = field->field->name;
+
+	if (field_name == NULL)
+		field_name = "";
+
+	return field_name;
+}
+
 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed)
 {
 	hist_field_fn_t fn = NULL;
 
 	switch (field_size) {
 	case 8:
 		if (field_is_signed)
 			fn = hist_field_s64;
@@ -648,34 +665,35 @@  static int is_descending(const char *str)
 		return 0;
 
 	return -EINVAL;
 }
 
 static int create_sort_keys(struct hist_trigger_data *hist_data)
 {
 	char *fields_str = hist_data->attrs->sort_key_str;
-	struct ftrace_event_field *field = NULL;
 	struct tracing_map_sort_key *sort_key;
 	int descending, ret = 0;
 	unsigned int i, j;
 
 	hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
 
 	if (!fields_str)
 		goto out;
 
 	strsep(&fields_str, "=");
 	if (!fields_str) {
 		ret = -EINVAL;
 		goto out;
 	}
 
 	for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
+		struct hist_field *hist_field;
 		char *field_str, *field_name;
+		const char *test_name;
 
 		sort_key = &hist_data->sort_keys[i];
 
 		field_str = strsep(&fields_str, ",");
 		if (!field_str) {
 			if (i == 0)
 				ret = -EINVAL;
 			break;
@@ -698,18 +716,20 @@  static int create_sort_keys(struct hist_trigger_data *hist_data)
 				ret = descending;
 				break;
 			}
 			sort_key->descending = descending;
 			continue;
 		}
 
 		for (j = 1; j < hist_data->n_fields; j++) {
-			field = hist_data->fields[j]->field;
-			if (field && (strcmp(field_name, field->name) == 0)) {
+			hist_field = hist_data->fields[j];
+			test_name = hist_field_name(hist_field, 0);
+
+			if (strcmp(field_name, test_name) == 0) {
 				sort_key->field_idx = j;
 				descending = is_descending(field_str);
 				if (descending < 0) {
 					ret = descending;
 					goto out;
 				}
 				sort_key->descending = descending;
 				break;
@@ -947,92 +967,93 @@  static void hist_trigger_stacktrace_print(struct seq_file *m,
 static void
 hist_trigger_entry_print(struct seq_file *m,
 			 struct hist_trigger_data *hist_data, void *key,
 			 struct tracing_map_elt *elt)
 {
 	struct hist_field *key_field;
 	char str[KSYM_SYMBOL_LEN];
 	bool multiline = false;
+	const char *field_name;
 	unsigned int i;
 	u64 uval;
 
 	seq_puts(m, "{ ");
 
 	for_each_hist_key_field(i, hist_data) {
 		key_field = hist_data->fields[i];
 
 		if (i > hist_data->n_vals)
 			seq_puts(m, ", ");
 
+		field_name = hist_field_name(key_field, 0);
+
 		if (key_field->flags & HIST_FIELD_FL_HEX) {
 			uval = *(u64 *)(key + key_field->offset);
-			seq_printf(m, "%s: %llx",
-				   key_field->field->name, uval);
+			seq_printf(m, "%s: %llx", field_name, uval);
 		} else if (key_field->flags & HIST_FIELD_FL_SYM) {
 			uval = *(u64 *)(key + key_field->offset);
 			sprint_symbol_no_offset(str, uval);
-			seq_printf(m, "%s: [%llx] %-45s",
-				   key_field->field->name, uval, str);
+			seq_printf(m, "%s: [%llx] %-45s", field_name,
+				   uval, str);
 		} else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
 			uval = *(u64 *)(key + key_field->offset);
 			sprint_symbol(str, uval);
-			seq_printf(m, "%s: [%llx] %-55s",
-				   key_field->field->name, uval, str);
+			seq_printf(m, "%s: [%llx] %-55s", field_name,
+				   uval, str);
 		} else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
 			char *comm = elt->private_data;
 
 			uval = *(u64 *)(key + key_field->offset);
-			seq_printf(m, "%s: %-16s[%10llu]",
-				   key_field->field->name, comm, uval);
+			seq_printf(m, "%s: %-16s[%10llu]", field_name,
+				   comm, uval);
 		} else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
 			const char *syscall_name;
 
 			uval = *(u64 *)(key + key_field->offset);
 			syscall_name = get_syscall_name(uval);
 			if (!syscall_name)
 				syscall_name = "unknown_syscall";
 
-			seq_printf(m, "%s: %-30s[%3llu]",
-				   key_field->field->name, syscall_name, uval);
+			seq_printf(m, "%s: %-30s[%3llu]", field_name,
+				   syscall_name, uval);
 		} else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
 			seq_puts(m, "stacktrace:\n");
 			hist_trigger_stacktrace_print(m,
 						      key + key_field->offset,
 						      HIST_STACKTRACE_DEPTH);
 			multiline = true;
 		} else if (key_field->flags & HIST_FIELD_FL_LOG2) {
-			seq_printf(m, "%s: ~ 2^%-2llu", key_field->field->name,
+			seq_printf(m, "%s: ~ 2^%-2llu", field_name,
 				   *(u64 *)(key + key_field->offset));
 		} else if (key_field->flags & HIST_FIELD_FL_STRING) {
-			seq_printf(m, "%s: %-50s", key_field->field->name,
+			seq_printf(m, "%s: %-50s", field_name,
 				   (char *)(key + key_field->offset));
 		} else {
 			uval = *(u64 *)(key + key_field->offset);
-			seq_printf(m, "%s: %10llu", key_field->field->name,
-				   uval);
+			seq_printf(m, "%s: %10llu", field_name, uval);
 		}
 	}
 
 	if (!multiline)
 		seq_puts(m, " ");
 
 	seq_puts(m, "}");
 
 	seq_printf(m, " hitcount: %10llu",
 		   tracing_map_read_sum(elt, HITCOUNT_IDX));
 
 	for (i = 1; i < hist_data->n_vals; i++) {
+		field_name = hist_field_name(hist_data->fields[i], 0);
+
 		if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
-			seq_printf(m, "  %s: %10llx",
-				   hist_data->fields[i]->field->name,
+			seq_printf(m, "  %s: %10llx", field_name,
 				   tracing_map_read_sum(elt, i));
 		} else {
-			seq_printf(m, "  %s: %10llu",
-				   hist_data->fields[i]->field->name,
+			seq_printf(m, "  %s: %10llu", field_name,
 				   tracing_map_read_sum(elt, i));
 		}
 	}
 
 	seq_puts(m, "\n");
 }
 
 static int print_entries(struct seq_file *m,
@@ -1135,17 +1156,19 @@  static const char *get_hist_field_flags(struct hist_field *hist_field)
 	else if (hist_field->flags & HIST_FIELD_FL_LOG2)
 		flags_str = "log2";
 
 	return flags_str;
 }
 
 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
 {
-	seq_printf(m, "%s", hist_field->field->name);
+	const char *field_name = hist_field_name(hist_field, 0);
+
+	seq_printf(m, "%s", field_name);
 	if (hist_field->flags) {
 		const char *flags_str = get_hist_field_flags(hist_field);
 
 		if (flags_str)
 			seq_printf(m, ".%s", flags_str);
 	}
 }