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([2600:6c56:7d00:582f::64e]) by smtp.googlemail.com with ESMTPSA id 586e51a60fabf-306e1c4e079sm245752fac.11.2025.07.23.21.09.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 23 Jul 2025 21:09:54 -0700 (PDT) Message-ID: Date: Wed, 23 Jul 2025 23:09:53 -0500 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Ping: How should userland app be notified when kernel comes out of suspend or hibernation? To: mcron-lsfnyl@rdmp.org, linux-pm@vger.kernel.org References: <1e2af6bddb8cd51e5076285659a6f5bc92b026f9.camel@rdmp.org> Content-Language: en-US From: Russell Haley In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/1/25 11:54 AM, Dale Mellor wrote: > Just bouncing this back up. Is anybody able to give any advice? > Thanks in advance. TFD_TIMER_CANCEL_ON_SET flag, perhaps? Maybe for belt-and-suspenders, check wallclock time before taking any action. I think a descehdule/suspend/resume can happen between any two CPU instructions though, so I don't think there's any way to save you from the ToC/ToU problem. Good luck, Russell