Commit 3e278c0d authored by Namhyung Kim's avatar Namhyung Kim Committed by Steven Rostedt (VMware)
Browse files

ftrace: Factor out __ftrace_hash_move() 

The __ftrace_hash_move() is to allocates properly-sized hash and move
entries in the src ftrace_hash.  It will be used to set function graph
filters which has nothing to do with the dyn_ftrace records.

Link: http://lkml.kernel.org/r/20170120024447.26097-1-namhyung@kernel.org



Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent 068f530b

kernel/trace/ftrace.c

+24 −16
Original line number Diff line number Diff line
@@ -1383,9 +1383,8 @@ ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); 
static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops,

				       struct ftrace_hash *new_hash);



static int

ftrace_hash_move(struct ftrace_ops *ops, int enable,

		 struct ftrace_hash **dst, struct ftrace_hash *src)

static struct ftrace_hash *

__ftrace_hash_move(struct ftrace_hash *src)

{

	struct ftrace_func_entry *entry;

	struct hlist_node *tn;
@@ -1393,21 +1392,13 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable, 
	struct ftrace_hash *new_hash;

	int size = src->count;

	int bits = 0;

	int ret;

	int i;



	/* Reject setting notrace hash on IPMODIFY ftrace_ops */

	if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable)

		return -EINVAL;



	/*

	 * If the new source is empty, just free dst and assign it

	 * the empty_hash.

	 * If the new source is empty, just return the empty_hash.

	 */

	if (!src->count) {

		new_hash = EMPTY_HASH;

		goto update;

	}

	if (!src->count)

		return EMPTY_HASH;



	/*

	 * Make the hash size about 1/2 the # found
@@ -1421,7 +1412,7 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable, 


	new_hash = alloc_ftrace_hash(bits);

	if (!new_hash)

		return -ENOMEM;

		return NULL;



	size = 1 << src->size_bits;

	for (i = 0; i < size; i++) {
@@ -1432,7 +1423,24 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable, 
		}

	}



update:

	return new_hash;

}



static int

ftrace_hash_move(struct ftrace_ops *ops, int enable,

		 struct ftrace_hash **dst, struct ftrace_hash *src)

{

	struct ftrace_hash *new_hash;

	int ret;



	/* Reject setting notrace hash on IPMODIFY ftrace_ops */

	if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable)

		return -EINVAL;



	new_hash = __ftrace_hash_move(src);

	if (!new_hash)

		return -ENOMEM;



	/* Make sure this can be applied if it is IPMODIFY ftrace_ops */

	if (enable) {

		/* IPMODIFY should be updated only when filter_hash updating */

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