1 files changed, 170 insertions, 41 deletions

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 0207aeed31e6..a6061a69aa84 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -65,7 +65,8 @@
 	C(INVALID_SORT_MODIFIER,"Invalid sort modifier"),		\
 	C(EMPTY_SORT_FIELD,	"Empty sort field"),			\
 	C(TOO_MANY_SORT_FIELDS,	"Too many sort fields (Max = 2)"),	\
-	C(INVALID_SORT_FIELD,	"Sort field must be a key or a val"),
+	C(INVALID_SORT_FIELD,	"Sort field must be a key or a val"),	\
+	C(INVALID_STR_OPERAND,	"String type can not be an operand in expression"),
 
 #undef C
 #define C(a, b)		HIST_ERR_##a
@@ -120,6 +121,7 @@ struct hist_field {
 	unsigned int			size;
 	unsigned int			offset;
 	unsigned int                    is_signed;
+	unsigned long			buckets;
 	const char			*type;
 	struct hist_field		*operands[HIST_FIELD_OPERANDS_MAX];
 	struct hist_trigger_data	*hist_data;
@@ -218,6 +220,27 @@ static u64 hist_field_log2(struct hist_field *hist_field,
 	return (u64) ilog2(roundup_pow_of_two(val));
 }
 
+static u64 hist_field_bucket(struct hist_field *hist_field,
+			     struct tracing_map_elt *elt,
+			     struct trace_buffer *buffer,
+			     struct ring_buffer_event *rbe,
+			     void *event)
+{
+	struct hist_field *operand = hist_field->operands[0];
+	unsigned long buckets = hist_field->buckets;
+
+	u64 val = operand->fn(operand, elt, buffer, rbe, event);
+
+	if (WARN_ON_ONCE(!buckets))
+		return val;
+
+	if (val >= LONG_MAX)
+		val = div64_ul(val, buckets);
+	else
+		val = (u64)((unsigned long)val / buckets);
+	return val * buckets;
+}
+
 static u64 hist_field_plus(struct hist_field *hist_field,
 			   struct tracing_map_elt *elt,
 			   struct trace_buffer *buffer,
@@ -317,6 +340,7 @@ enum hist_field_flags {
 	HIST_FIELD_FL_VAR_REF		= 1 << 14,
 	HIST_FIELD_FL_CPU		= 1 << 15,
 	HIST_FIELD_FL_ALIAS		= 1 << 16,
+	HIST_FIELD_FL_BUCKET		= 1 << 17,
 };
 
 struct var_defs {
@@ -484,7 +508,8 @@ struct track_data {
 struct hist_elt_data {
 	char *comm;
 	u64 *var_ref_vals;
-	char *field_var_str[SYNTH_FIELDS_MAX];
+	char **field_var_str;
+	int n_field_var_str;
 };
 
 struct snapshot_context {
@@ -1108,10 +1133,11 @@ static const char *hist_field_name(struct hist_field *field,
 	if (field->field)
 		field_name = field->field->name;
 	else if (field->flags & HIST_FIELD_FL_LOG2 ||
-		 field->flags & HIST_FIELD_FL_ALIAS)
+		 field->flags & HIST_FIELD_FL_ALIAS ||
+		 field->flags & HIST_FIELD_FL_BUCKET)
 		field_name = hist_field_name(field->operands[0], ++level);
 	else if (field->flags & HIST_FIELD_FL_CPU)
-		field_name = "cpu";
+		field_name = "common_cpu";
 	else if (field->flags & HIST_FIELD_FL_EXPR ||
 		 field->flags & HIST_FIELD_FL_VAR_REF) {
 		if (field->system) {
@@ -1376,9 +1402,11 @@ static void hist_elt_data_free(struct hist_elt_data *elt_data)
 {
 	unsigned int i;
 
-	for (i = 0; i < SYNTH_FIELDS_MAX; i++)
+	for (i = 0; i < elt_data->n_field_var_str; i++)
 		kfree(elt_data->field_var_str[i]);
 
+	kfree(elt_data->field_var_str);
+
 	kfree(elt_data->comm);
 	kfree(elt_data);
 }
@@ -1395,17 +1423,17 @@ static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
 	struct hist_trigger_data *hist_data = elt->map->private_data;
 	unsigned int size = TASK_COMM_LEN;
 	struct hist_elt_data *elt_data;
-	struct hist_field *key_field;
+	struct hist_field *hist_field;
 	unsigned int i, n_str;
 
 	elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
 	if (!elt_data)
 		return -ENOMEM;
 
-	for_each_hist_key_field(i, hist_data) {
-		key_field = hist_data->fields[i];
+	for_each_hist_field(i, hist_data) {
+		hist_field = hist_data->fields[i];
 
-		if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
+		if (hist_field->flags & HIST_FIELD_FL_EXECNAME) {
 			elt_data->comm = kzalloc(size, GFP_KERNEL);
 			if (!elt_data->comm) {
 				kfree(elt_data);
@@ -1426,6 +1454,13 @@ static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
 
 	size = STR_VAR_LEN_MAX;
 
+	elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL);
+	if (!elt_data->field_var_str) {
+		hist_elt_data_free(elt_data);
+		return -EINVAL;
+	}
+	elt_data->n_field_var_str = n_str;
+
 	for (i = 0; i < n_str; i++) {
 		elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
 		if (!elt_data->field_var_str[i]) {
@@ -1469,6 +1504,8 @@ static const char *get_hist_field_flags(struct hist_field *hist_field)
 		flags_str = "syscall";
 	else if (hist_field->flags & HIST_FIELD_FL_LOG2)
 		flags_str = "log2";
+	else if (hist_field->flags & HIST_FIELD_FL_BUCKET)
+		flags_str = "buckets";
 	else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
 		flags_str = "usecs";
 
@@ -1589,7 +1626,9 @@ static void __destroy_hist_field(struct hist_field *hist_field)
 
 	kfree(hist_field->var.name);
 	kfree(hist_field->name);
-	kfree(hist_field->type);
+
+	/* Can likely be a const */
+	kfree_const(hist_field->type);
 
 	kfree(hist_field->system);
 	kfree(hist_field->event_name);
@@ -1646,9 +1685,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	if (flags & HIST_FIELD_FL_HITCOUNT) {
 		hist_field->fn = hist_field_counter;
 		hist_field->size = sizeof(u64);
-		hist_field->type = kstrdup("u64", GFP_KERNEL);
-		if (!hist_field->type)
-			goto free;
+		hist_field->type = "u64";
 		goto out;
 	}
 
@@ -1657,12 +1694,13 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 		goto out;
 	}
 
-	if (flags & HIST_FIELD_FL_LOG2) {
-		unsigned long fl = flags & ~HIST_FIELD_FL_LOG2;
-		hist_field->fn = hist_field_log2;
+	if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) {
+		unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET);
+		hist_field->fn = flags & HIST_FIELD_FL_LOG2 ? hist_field_log2 :
+			hist_field_bucket;
 		hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
 		hist_field->size = hist_field->operands[0]->size;
-		hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL);
+		hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL);
 		if (!hist_field->type)
 			goto free;
 		goto out;
@@ -1671,29 +1709,27 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	if (flags & HIST_FIELD_FL_TIMESTAMP) {
 		hist_field->fn = hist_field_timestamp;
 		hist_field->size = sizeof(u64);
-		hist_field->type = kstrdup("u64", GFP_KERNEL);
-		if (!hist_field->type)
-			goto free;
+		hist_field->type = "u64";
 		goto out;
 	}
 
 	if (flags & HIST_FIELD_FL_CPU) {
 		hist_field->fn = hist_field_cpu;
 		hist_field->size = sizeof(int);
-		hist_field->type = kstrdup("unsigned int", GFP_KERNEL);
-		if (!hist_field->type)
-			goto free;
+		hist_field->type = "unsigned int";
 		goto out;
 	}
 
 	if (WARN_ON_ONCE(!field))
 		goto out;
 
-	if (is_string_field(field)) {
+	/* Pointers to strings are just pointers and dangerous to dereference */
+	if (is_string_field(field) &&
+	    (field->filter_type != FILTER_PTR_STRING)) {
 		flags |= HIST_FIELD_FL_STRING;
 
 		hist_field->size = MAX_FILTER_STR_VAL;
-		hist_field->type = kstrdup(field->type, GFP_KERNEL);
+		hist_field->type = kstrdup_const(field->type, GFP_KERNEL);
 		if (!hist_field->type)
 			goto free;
 
@@ -1706,7 +1742,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	} else {
 		hist_field->size = field->size;
 		hist_field->is_signed = field->is_signed;
-		hist_field->type = kstrdup(field->type, GFP_KERNEL);
+		hist_field->type = kstrdup_const(field->type, GFP_KERNEL);
 		if (!hist_field->type)
 			goto free;
 
@@ -1792,7 +1828,7 @@ static int init_var_ref(struct hist_field *ref_field,
 		}
 	}
 
-	ref_field->type = kstrdup(var_field->type, GFP_KERNEL);
+	ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL);
 	if (!ref_field->type) {
 		err = -ENOMEM;
 		goto free;
@@ -1950,7 +1986,7 @@ static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
 
 static struct ftrace_event_field *
 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
-	    char *field_str, unsigned long *flags)
+	    char *field_str, unsigned long *flags, unsigned long *buckets)
 {
 	struct ftrace_event_field *field = NULL;
 	char *field_name, *modifier, *str;
@@ -1977,7 +2013,22 @@ parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
 			*flags |= HIST_FIELD_FL_LOG2;
 		else if (strcmp(modifier, "usecs") == 0)
 			*flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
-		else {
+		else if (strncmp(modifier, "bucket", 6) == 0) {
+			int ret;
+
+			modifier += 6;
+
+			if (*modifier == 's')
+				modifier++;
+			if (*modifier != '=')
+				goto error;
+			modifier++;
+			ret = kstrtoul(modifier, 0, buckets);
+			if (ret || !(*buckets))
+				goto error;
+			*flags |= HIST_FIELD_FL_BUCKET;
+		} else {
+ error:
 			hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier));
 			field = ERR_PTR(-EINVAL);
 			goto out;
@@ -1989,14 +2040,24 @@ parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
 		hist_data->enable_timestamps = true;
 		if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
 			hist_data->attrs->ts_in_usecs = true;
-	} else if (strcmp(field_name, "cpu") == 0)
+	} else if (strcmp(field_name, "common_cpu") == 0)
 		*flags |= HIST_FIELD_FL_CPU;
 	else {
 		field = trace_find_event_field(file->event_call, field_name);
 		if (!field || !field->size) {
-			hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, errpos(field_name));
-			field = ERR_PTR(-EINVAL);
-			goto out;
+			/*
+			 * For backward compatibility, if field_name
+			 * was "cpu", then we treat this the same as
+			 * common_cpu.
+			 */
+			if (strcmp(field_name, "cpu") == 0) {
+				*flags |= HIST_FIELD_FL_CPU;
+			} else {
+				hist_err(tr, HIST_ERR_FIELD_NOT_FOUND,
+					 errpos(field_name));
+				field = ERR_PTR(-EINVAL);
+				goto out;
+			}
 		}
 	}
  out:
@@ -2036,6 +2097,7 @@ static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
 	char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
 	struct ftrace_event_field *field = NULL;
 	struct hist_field *hist_field = NULL;
+	unsigned long buckets = 0;
 	int ret = 0;
 
 	s = strchr(str, '.');
@@ -2073,7 +2135,7 @@ static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
 	} else
 		str = s;
 
-	field = parse_field(hist_data, file, str, flags);
+	field = parse_field(hist_data, file, str, flags, &buckets);
 	if (IS_ERR(field)) {
 		ret = PTR_ERR(field);
 		goto out;
@@ -2084,6 +2146,7 @@ static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
 		ret = -ENOMEM;
 		goto out;
 	}
+	hist_field->buckets = buckets;
 
 	return hist_field;
  out:
@@ -2144,6 +2207,13 @@ static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
 		ret = PTR_ERR(operand1);
 		goto free;
 	}
+	if (operand1->flags & HIST_FIELD_FL_STRING) {
+		/* String type can not be the operand of unary operator. */
+		hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
+		destroy_hist_field(operand1, 0);
+		ret = -EINVAL;
+		goto free;
+	}
 
 	expr->flags |= operand1->flags &
 		(HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
@@ -2151,7 +2221,7 @@ static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
 	expr->operands[0] = operand1;
 	expr->operator = FIELD_OP_UNARY_MINUS;
 	expr->name = expr_str(expr, 0);
-	expr->type = kstrdup(operand1->type, GFP_KERNEL);
+	expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
 	if (!expr->type) {
 		ret = -ENOMEM;
 		goto free;
@@ -2245,6 +2315,11 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
 		operand1 = NULL;
 		goto free;
 	}
+	if (operand1->flags & HIST_FIELD_FL_STRING) {
+		hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str));
+		ret = -EINVAL;
+		goto free;
+	}
 
 	/* rest of string could be another expression e.g. b+c in a+b+c */
 	operand_flags = 0;
@@ -2254,6 +2329,11 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
 		operand2 = NULL;
 		goto free;
 	}
+	if (operand2->flags & HIST_FIELD_FL_STRING) {
+		hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
+		ret = -EINVAL;
+		goto free;
+	}
 
 	ret = check_expr_operands(file->tr, operand1, operand2);
 	if (ret)
@@ -2275,9 +2355,13 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
 
 	expr->operands[0] = operand1;
 	expr->operands[1] = operand2;
+
+	/* The operand sizes should be the same, so just pick one */
+	expr->size = operand1->size;
+
 	expr->operator = field_op;
 	expr->name = expr_str(expr, 0);
-	expr->type = kstrdup(operand1->type, GFP_KERNEL);
+	expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
 	if (!expr->type) {
 		ret = -ENOMEM;
 		goto free;
@@ -2665,10 +2749,10 @@ static struct hist_field *create_var(struct hist_trigger_data *hist_data,
 	var->var.hist_data = var->hist_data = hist_data;
 	var->size = size;
 	var->var.name = kstrdup(name, GFP_KERNEL);
-	var->type = kstrdup(type, GFP_KERNEL);
+	var->type = kstrdup_const(type, GFP_KERNEL);
 	if (!var->var.name || !var->type) {
+		kfree_const(var->type);
 		kfree(var->var.name);
-		kfree(var->type);
 		kfree(var);
 		var = ERR_PTR(-ENOMEM);
 	}
@@ -3396,6 +3480,8 @@ trace_action_create_field_var(struct hist_trigger_data *hist_data,
 			event = data->match_data.event;
 		}
 
+		if (!event)
+			goto free;
 		/*
 		 * At this point, we're looking at a field on another
 		 * event.  Because we can't modify a hist trigger on
@@ -3695,6 +3781,41 @@ static int create_val_field(struct hist_trigger_data *hist_data,
 	return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
 }
 
+static const char *no_comm = "(no comm)";
+
+static u64 hist_field_execname(struct hist_field *hist_field,
+			       struct tracing_map_elt *elt,
+			       struct trace_buffer *buffer,
+			       struct ring_buffer_event *rbe,
+			       void *event)
+{
+	struct hist_elt_data *elt_data;
+
+	if (WARN_ON_ONCE(!elt))
+		return (u64)(unsigned long)no_comm;
+
+	elt_data = elt->private_data;
+
+	if (WARN_ON_ONCE(!elt_data->comm))
+		return (u64)(unsigned long)no_comm;
+
+	return (u64)(unsigned long)(elt_data->comm);
+}
+
+/* Convert a var that points to common_pid.execname to a string */
+static void update_var_execname(struct hist_field *hist_field)
+{
+	hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR |
+		HIST_FIELD_FL_EXECNAME;
+	hist_field->size = MAX_FILTER_STR_VAL;
+	hist_field->is_signed = 0;
+
+	kfree_const(hist_field->type);
+	hist_field->type = "char[]";
+
+	hist_field->fn = hist_field_execname;
+}
+
 static int create_var_field(struct hist_trigger_data *hist_data,
 			    unsigned int val_idx,
 			    struct trace_event_file *file,
@@ -3719,6 +3840,9 @@ static int create_var_field(struct hist_trigger_data *hist_data,
 
 	ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
 
+	if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME)
+		update_var_execname(hist_data->fields[val_idx]);
+
 	if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING)
 		hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++;
 
@@ -4495,8 +4619,6 @@ static inline void add_to_key(char *compound_key, void *key,
 		field = key_field->field;
 		if (field->filter_type == FILTER_DYN_STRING)
 			size = *(u32 *)(rec + field->offset) >> 16;
-		else if (field->filter_type == FILTER_PTR_STRING)
-			size = strlen(key);
 		else if (field->filter_type == FILTER_STATIC_STRING)
 			size = field->size;
 
@@ -4664,6 +4786,11 @@ static void hist_trigger_print_key(struct seq_file *m,
 		} else if (key_field->flags & HIST_FIELD_FL_LOG2) {
 			seq_printf(m, "%s: ~ 2^%-2llu", field_name,
 				   *(u64 *)(key + key_field->offset));
+		} else if (key_field->flags & HIST_FIELD_FL_BUCKET) {
+			unsigned long buckets = key_field->buckets;
+			uval = *(u64 *)(key + key_field->offset);
+			seq_printf(m, "%s: ~ %llu-%llu", field_name,
+				   uval, uval + buckets -1);
 		} else if (key_field->flags & HIST_FIELD_FL_STRING) {
 			seq_printf(m, "%s: %-50s", field_name,
 				   (char *)(key + key_field->offset));
@@ -5085,7 +5212,7 @@ static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
 		seq_printf(m, "%s=", hist_field->var.name);
 
 	if (hist_field->flags & HIST_FIELD_FL_CPU)
-		seq_puts(m, "cpu");
+		seq_puts(m, "common_cpu");
 	else if (field_name) {
 		if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
 		    hist_field->flags & HIST_FIELD_FL_ALIAS)
@@ -5103,6 +5230,8 @@ static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
 				seq_printf(m, ".%s", flags);
 		}
 	}
+	if (hist_field->buckets)
+		seq_printf(m, "=%ld", hist_field->buckets);
 }
 
 static int event_hist_trigger_print(struct seq_file *m,