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Sender: Guenter Roeck <groeck7@gmail.com>
Date:   Tue, 18 Jul 2023 21:08:06 -0700
From:   Guenter Roeck <linux@roeck-us.net>
To:     Bill O'Donnell <billodo@redhat.com>
Cc:     Rob Barnes <robbarnes@google.com>, bleung@chromium.org,
        linux-fsdevel@vger.kernel.org,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <brauner@kernel.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] fs: export emergency_sync
Message-ID: <ad539fad-999b-46cd-9372-a196469b4631@roeck-us.net>
References: <20230718214540.1.I763efc30c57dcc0284d81f704ef581cded8960c8@changeid>
 <ZLcOcr6N+Ty59rBD@redhat.com>
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On Tue, Jul 18, 2023 at 05:13:06PM -0500, Bill O'Donnell wrote:
> On Tue, Jul 18, 2023 at 09:45:40PM +0000, Rob Barnes wrote:
> > emergency_sync forces a filesystem sync in emergency situations.
> > Export this function so it can be used by modules.
> > 
> > Signed-off-by: Rob Barnes <robbarnes@google.com>
> 
> Example of an emergency situation?

An example from existing code in
drivers/firmware/arm_scmi/scmi_power_control.c:

static inline void
scmi_request_forceful_transition(struct scmi_syspower_conf *sc)
{
        dev_dbg(sc->dev, "Serving forceful request:%d\n",
                sc->required_transition);

#ifndef MODULE
        emergency_sync();
#endif

Arguably emergency_sync() should also be called if the file is built
as module.

Either case, I think it would make sense to add an example to the commit
description.

Thanks,
Guenter