public inbox for linux-trace-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Jiri Olsa <jolsa@kernel.org>
To: Steven Rostedt <rostedt@kernel.org>, Alexei Starovoitov <ast@kernel.org>
Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-trace-kernel@vger.kernel.org,
	Daniel Borkmann <daniel@iogearbox.net>,
	Andrii Nakryiko <andrii@kernel.org>,
	Menglong Dong <menglong8.dong@gmail.com>,
	Song Liu <song@kernel.org>
Subject: [PATCH bpf-next] ftrace: Use hash argument for tmp_ops in update_ftrace_direct_mod
Date: Thu, 12 Mar 2026 12:47:46 +0100	[thread overview]
Message-ID: <20260312114746.122174-1-jolsa@kernel.org> (raw)

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 is always a subset of the ops->func_hash.

Fixes: e93672f770d7 ("ftrace: Add update_ftrace_direct_mod function")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 kernel/trace/ftrace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8df69e702706..71dcbfeac86c 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -6608,7 +6608,7 @@ int update_ftrace_direct_mod(struct ftrace_ops *ops, struct ftrace_hash *hash, b
 
 	/* Enable the tmp_ops to have the same functions as the direct ops */
 	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)
-- 
2.53.0


             reply	other threads:[~2026-03-12 11:47 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-12 11:47 Jiri Olsa [this message]
2026-03-12 12:24 ` [PATCH bpf-next] ftrace: Use hash argument for tmp_ops in update_ftrace_direct_mod bot+bpf-ci
2026-03-12 12:38   ` Jiri Olsa

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260312114746.122174-1-jolsa@kernel.org \
    --to=jolsa@kernel.org \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-trace-kernel@vger.kernel.org \
    --cc=menglong8.dong@gmail.com \
    --cc=rostedt@kernel.org \
    --cc=song@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox