From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bob Peterson <rpeterso@redhat.com>
Date: Fri, 5 Jun 2020 10:48:52 -0400 (EDT)
Subject: [Cluster-devel] [PATCH 6/8] gfs2: instrumentation wrt log_flush
 stuck
In-Reply-To: <CAHc6FU6Zo3gQCRt=rj8Xf3yyf4T8uX1vfHL9L1DJy3L90XkARQ@mail.gmail.com>
References: <20200526130536.295081-1-rpeterso@redhat.com>
	<20200526130536.295081-7-rpeterso@redhat.com>
	<CAHc6FU6Zo3gQCRt=rj8Xf3yyf4T8uX1vfHL9L1DJy3L90XkARQ@mail.gmail.com>
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Hi Andreas,

----- Original Message -----
(snip)
> > @@ -970,7 +969,16 @@ void gfs2_log_flush(struct gfs2_sbd *sdp, struct
> > gfs2_glock *gl, u32 flags)
> >
> >         if (!(flags & GFS2_LOG_HEAD_FLUSH_NORMAL)) {
> >                 if (!sdp->sd_log_idle) {
> > +                       unsigned long start = jiffies;
> > +
> >                         for (;;) {
> > +                               if (time_after(jiffies, start + (HZ *
> > 600))) {
> 
> This should probably have some rate limiting as well, for example:

Seems unnecessary. If the log flush gets stuck, the message will be printed
once, and at most every 10 minutes.
 
>                                         start = jiffies;
> 
> I'm not sure what provides similar rate limiting in gfs2_ail1_flush.
> 
> > +                                       fs_err(sdp, "Error: In
> > gfs2_log_flush "
> > +                                              "for 10 minutes! t=%d\n",
> > +                                              current->journal_info ? 1 :
> > 0);
> 
> Please don't break the format string up like that; this makes grepping
> harder.

How do you propose I break present it without going over 80 character?
I could #define it as a constant, or put it into a separate function
that has less indentation, I suppose.
 
Bob