[Linux-cluster] Re: GFS, what's remaining

[Jörn Engel]

On Fri, 2 September 2005 17:44:03 +0800, David Teigland wrote:
> On Thu, Sep 01, 2005 at 01:35:23PM +0200, Arjan van de Ven wrote:
> 
> > +	gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_count) > 0,);
> 
> > what is gfs2_assert() about anyway? please just use BUG_ON directly
> > everywhere
> 
> When a machine has many gfs file systems mounted at once it can be useful
> to know which one failed.  Does the following look ok?
> 
> #define gfs2_assert(sdp, assertion)                                       \
> do {                                                                      \
>         if (unlikely(!(assertion))) {                                     \
>                 printk(KERN_ERR                                           \
>                         "GFS2: fsid=%s: fatal: assertion \"%s\" failed\n" \
>                         "GFS2: fsid=%s:   function = %s\n"                \
>                         "GFS2: fsid=%s:   file = %s, line = %u\n"         \
>                         "GFS2: fsid=%s:   time = %lu\n",                  \
>                         sdp->sd_fsname, # assertion,                      \
>                         sdp->sd_fsname,  __FUNCTION__,                    \
>                         sdp->sd_fsname, __FILE__, __LINE__,               \
>                         sdp->sd_fsname, get_seconds());                   \
>                 BUG();                                                    \
>         }                                                                 \
> } while (0)

That's a lot of string constants.  I'm not sure how smart current
versions of gcc are, but older ones created a new constant for each
invocation of such a macro, iirc.  So you might want to move the code
out of line.

Jörn

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