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Date:   Fri, 11 Sep 2020 11:32:21 +0200
From:   peterz@infradead.org
To:     Gabriel Krisman Bertazi <krisman@collabora.com>
Cc:     luto@kernel.org, tglx@linutronix.de, keescook@chromium.org,
        x86@kernel.org, linux-kernel@vger.kernel.org,
        linux-api@vger.kernel.org, willy@infradead.org,
        linux-kselftest@vger.kernel.org, shuah@kernel.org,
        kernel@collabora.com
Subject: Re: [PATCH v6 1/9] kernel: Support TIF_SYSCALL_INTERCEPT flag
Message-ID: <20200911093221.GD1362448@hirez.programming.kicks-ass.net>
References: <20200904203147.2908430-1-krisman@collabora.com>
 <20200904203147.2908430-2-krisman@collabora.com>
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On Fri, Sep 04, 2020 at 04:31:39PM -0400, Gabriel Krisman Bertazi wrote:
> +static inline void __set_tsk_syscall_intercept(struct task_struct *tsk,
> +					   unsigned int type)
> +{
> +	tsk->syscall_intercept |= type;
> +
> +	if (tsk->syscall_intercept)
> +		set_tsk_thread_flag(tsk, TIF_SYSCALL_INTERCEPT);
> +}

Did the above want to be:

	unsigned int old = tsk->syscall_intercept;
	tsk->syscall_intercept |= type;
	if (!old)
		set_tsk_thread_flag(tsk, TIF_SYSCALL_INTERCEPT)

?

> +static inline void __clear_tsk_syscall_intercept(struct task_struct *tsk,
> +					     unsigned int type)
> +{
> +	tsk->syscall_intercept &= ~type;
> +
> +	if (tsk->syscall_intercept == 0)
> +		clear_tsk_thread_flag(tsk, TIF_SYSCALL_INTERCEPT);
> +}