[lustre-devel] [PATCH v3 04/13] lustre: libcfs: fix cfs_print_to_console()

[James Simmons]

> > The original code for cfs_print_to_console() used printk() and
> > used tricks to select which printk level to use. Later a cleanup
> > patch landed the just converted printk directly to pr_info which
> > is not exactly correct. Instead of converting back to printk lets
> > move everything to pr_* type functions which simplify the code.
> > This allows us to fold both dbghdr_to_err_string() and the
> > function dbghdr_to_info_string() into cfs_print_to_console().
> > 
> > Signed-off-by: James Simmons <jsimmons at infradead.org>
> > ---
> > .../staging/lustre/lnet/libcfs/linux-tracefile.c   | 55 ++++++----------------
> > 1 file changed, 14 insertions(+), 41 deletions(-)
> > 
> > diff --git a/drivers/staging/lustre/lnet/libcfs/linux-tracefile.c b/drivers/staging/lustre/lnet/libcfs/linux-tracefile.c
> > index 3af7722..c1747c4 100644
> > --- a/drivers/staging/lustre/lnet/libcfs/linux-tracefile.c
> > +++ b/drivers/staging/lustre/lnet/libcfs/linux-tracefile.c
> > @@ -140,54 +140,27 @@ enum cfs_trace_buf_type cfs_trace_buf_idx_get(void)
> > void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
> > 			  const char *buf, int len, const char *file,
> > 			  const char *fn)
> > {
> > +	char *prefix = "Lustre";
> > +
> > +	if (hdr->ph_subsys == S_LND || hdr->ph_subsys == S_LNET)
> > +		prefix = "LNet";
> > 
> > -	if (mask & D_EMERG) {
> > -		prefix = dbghdr_to_err_string(hdr);
> > -		ptype = KERN_EMERG;
> > +	if (mask & (D_CONSOLE | libcfs_printk)) {
> 
> This check is broken.  The default value of libcfs_printk (the mask
> that controls which messages should be printed to the console, and
> which ones should only be logged into the internal buffer) is:
> 
>     #define D_CANTMASK (D_ERROR | D_EMERG | D_WARNING | D_CONSOLE)
> 
> so that means virtually every console message will be printed with
> pr_info() because this is matched first, instead of pr_emerg() or
> pr_err() below.
> 
> That is why the previous code was matching D_EMERG and D_ERROR first,
> then D_WARNING, and (D_CONSOLE | libcfs_printk) at the end.

So to do this right we need:

static void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
                                 const char *buf, int len, const char 
*file,
                                 const char *fn)
{
        char *prefix = "Lustre";

        if (hdr->ph_subsys == S_LND || hdr->ph_subsys == S_LNET)
                prefix = "LNet";

        if (mask & D_CONSOLE) {
                if (mask & D_EMERG) {
                        pr_emerg("%sError: %.*s", prefix, len, buf);
                } else if (mask & D_ERROR) {
                        pr_err("%sError: %.*s", prefix, len, buf);
                } else if (mask & D_WARNING) {
                        pr_warn("%s: %.*s", prefix, len, buf);
                } else if (mask & libcfs_printk) {
                        pr_info("%s: %.*s", prefix, len, buf);
                }
        } else {
                if (mask & D_EMERG) {
                        pr_emerg("%sError: %d:%d:(%s:%d:%s()) %.*s", prefix,
                                 hdr->ph_pid, hdr->ph_extern_pid, file,
                                 hdr->ph_line_num, fn, len, buf);
                } else if (mask & D_ERROR) {
                        pr_err("%sError: %d:%d:(%s:%d:%s()) %.*s", prefix,
                               hdr->ph_pid, hdr->ph_extern_pid, file,
                               hdr->ph_line_num, fn, len, buf);
                } else if (mask & D_WARNING) {
                        pr_warn("%s: %d:%d:(%s:%d:%s()) %.*s", prefix,
                                hdr->ph_pid, hdr->ph_extern_pid, file,
                                hdr->ph_line_num, fn, len, buf);
                } else if (mask & libcfs_printk) {
                        pr_info("%s: %.*s", prefix, len, buf);
                }
        }
}