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Date:   Thu, 10 Nov 2022 19:16:51 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc:     linux-kernel <linux-kernel@vger.kernel.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        "rcu@vger.kernel.org" <rcu@vger.kernel.org>,
        "kernel-dev@igalia.com" <kernel-dev@igalia.com>,
        "Guilherme G. Piccoli" <kernel@gpiccoli.net>
Subject: Re: RCU stall on 6.1-rc4 (and some previous releases) related to
 ftrace
Message-ID: <20221110191651.3a177417@rorschach.local.home>
In-Reply-To: <1ef5fe19-a82f-835e-fda5-455e9c2b94b4@igalia.com>
References: <1ef5fe19-a82f-835e-fda5-455e9c2b94b4@igalia.com>
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On Thu, 10 Nov 2022 18:25:41 -0300
"Guilherme G. Piccoli" <gpiccoli@igalia.com> wrote:

> @@ -4184,6 +4184,7 @@ match_records(struct ftrace_hash *hash, char *func, int len, char *mod)
>  		if (rec->flags & FTRACE_FL_DISABLED)
>  			continue;
>  
> +		cond_resched();
>  		if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) {
>  			ret = enter_record(hash, rec, clear_filter);
>  			if (ret < 0) {

This isn't where I would put it. I would add it after the if statement.
That is, at the end of the loop.

-- Steve