Re: [PATCH v2 2/5] ftrace: Do not add duplicate entries in subops manager ops
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Date: 2025-02-20 06:59:47
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On Wed, 19 Feb 2025 17:04:38 -0500 Steven Rostedt [off-list ref] wrote:
From: Steven Rostedt <rostedt@goodmis.org>
Check if a function is already in the manager ops of a subops. A manager
ops contains multiple subops, and if two or more subops are tracing the
same function, the manager ops only needs a single entry in its hash.
Cc: stable@vger.kernel.org
Fixes: 4f554e955614f ("ftrace: Add ftrace_set_filter_ips function")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>Looks good to me. Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Thank you,
quoted hunk ↗ jump to hunk
--- kernel/trace/ftrace.c | 3 +++ 1 file changed, 3 insertions(+)diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 03b35a05808c..189eb0a12f4b 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c@@ -5717,6 +5717,9 @@ __ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) return -ENOENT; free_hash_entry(hash, entry); return 0; + } else if (__ftrace_lookup_ip(hash, ip) != NULL) { + /* Already exists */ + return 0; } entry = add_hash_entry(hash, ip);-- 2.47.2
-- Masami Hiramatsu (Google) [off-list ref]