Commit 50b35c9e authored by Jiri Olsa's avatar Jiri Olsa Committed by Steven Rostedt (Google)
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ftrace: Use hash argument for tmp_ops in update_ftrace_direct_mod 

The modify logic registers temporary ftrace_ops object (tmp_ops) to trigger
the slow path for all direct callers to be able to safely modify attached
addresses.

At the moment we use ops->func_hash for tmp_ops filter, which represents all
the systems attachments. It's faster to use just the passed hash filter, which
contains only the modified sites and is always a subset of the ops->func_hash.

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Menglong Dong <menglong8.dong@gmail.com>
Cc: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/20260312123738.129926-1-jolsa@kernel.org


Fixes: e93672f7 ("ftrace: Add update_ftrace_direct_mod function")
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent f35dbac6

kernel/trace/ftrace.c

+2 −2
Original line number Diff line number Diff line
@@ -6606,9 +6606,9 @@ int update_ftrace_direct_mod(struct ftrace_ops *ops, struct ftrace_hash *hash, b 
	if (!orig_hash)

		goto unlock;



	/* Enable the tmp_ops to have the same functions as the direct ops */

	/* Enable the tmp_ops to have the same functions as the hash object. */

	ftrace_ops_init(&tmp_ops);

	tmp_ops.func_hash = ops->func_hash;

	tmp_ops.func_hash->filter_hash = hash;



	err = register_ftrace_function_nolock(&tmp_ops);

	if (err)