drivers-core: make structured logging play nice with dynamic-debug

commit c4e00daaa96d3a0786f1f4fe6456281c60ef9a16 changed __dev_printk
in a way that broke dynamic-debug's ability to control the dynamic
prefix of dev_dbg(dev,..), but not dev_dbg(NULL,..) or pr_debug(..),
which is why it wasnt noticed sooner.

When dev==NULL, __dev_printk() just calls printk(), which just works.
But otherwise, it assumed that level was always a string like "<L>"
and just plucked out the 'L', ignoring the rest.  However,
dynamic_emit_prefix() adds "[tid] module:func:line:" to the string,
those additions all got lost.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Cc: stable <stable@vger.kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 7 insertions, 2 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index f338037a4f3d..cdd01c52c629 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1865,6 +1865,7 @@ int __dev_printk(const char *level, const struct device *dev,
                  struct va_format *vaf)
 {
         char dict[128];
+        const char *level_extra = "";
         size_t dictlen = 0;
         const char *subsys;
 
@@ -1911,10 +1912,14 @@ int __dev_printk(const char *level, const struct device *dev,
                                     "DEVICE=+%s:%s", subsys, dev_name(dev));
         }
 skip:
+        if (level[3])
+                level_extra = &level[3]; /* skip past "<L>" */
+
         return printk_emit(0, level[1] - '0',
                            dictlen ? dict : NULL, dictlen,
-                           "%s %s: %pV",
-                           dev_driver_string(dev), dev_name(dev), vaf);
+                           "%s %s: %s%pV",
+                           dev_driver_string(dev), dev_name(dev),
+                           level_extra, vaf);
 }
 EXPORT_SYMBOL(__dev_printk);