From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oleg Nesterov Subject: Re: [PATCH/RFC] signal: Export signal_wake_up_state() to modules Date: Sat, 6 May 2017 21:42:56 +0200 Message-ID: <20170506194256.GA21726@redhat.com> References: <1493977751-19340-1-git-send-email-geert+renesas@glider.be> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Ingo Molnar , Peter Zijlstra , Thomas Gleixner , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Geert Uytterhoeven Return-path: Content-Disposition: inline In-Reply-To: <1493977751-19340-1-git-send-email-geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: On 05/05, Geert Uytterhoeven wrote: > > I'm using signal_wake_up() to abort a task blocked on > wait_for_completion_interruptible(), cfr. sh_msiof_slave_abort() in > "spi: sh-msiof: Add slave mode support" > (http://www.spinics.net/lists/devicetree/msg175575.html). > > Is exporting signal_wake_up_state() an acceptable solution? > Alternatively, I can extract the code to abort an completion into a > generic abort_completion() function, and export that. I too do not think this is a good idea... signal_wake_up() or even set_tsk_thread_flag() should never be used unless you actually send a signal. Yes, freeze_task() does this too but note that recalc_sigpending() checks freezing() and in this case we really want the target to enter the get_signal() path. And in fact I do not really understand why do you need it, it seems that you can easily rework this code and avoid this hack. Not to mention that sh_msiof_slave_abort() plays with struct completion internals, this doesn't look good too. Finally, clear_thread_flag(TIF_SIGPENDING) in sh_msiof_wait_for_completion() looks wrong. Or it is only for kthreads? Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html