netdev_printk/dynamic_netdev_dbg: Directly call printk_emit

A lot of stack is used in recursive printks with %pV.

Using multiple levels of %pV (a logging function with %pV
that calls another logging function with %pV) can consume
more stack than necessary.

Avoid excessive stack use by not calling dev_printk from
netdev_printk and dynamic_netdev_dbg.  Duplicate the logic
and form of dev_printk instead.

Make __netdev_printk static.
Remove EXPORT_SYMBOL(__netdev_printk)
Whitespace and brace style neatening.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 59dc05f..5f49cc0 100644 (file)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2720,9 +2720,6 @@ static inline const char *netdev_name(const struct net_device *dev)
        return dev->name;
 }
 
-extern int __netdev_printk(const char *level, const struct net_device *dev,
-                       struct va_format *vaf);
-
 extern __printf(3, 4)
 int netdev_printk(const char *level, const struct net_device *dev,
                  const char *format, ...);

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 29ff2e4..2a29f4e 100644 (file)
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -611,20 +611,40 @@ EXPORT_SYMBOL(__dynamic_dev_dbg);
 #ifdef CONFIG_NET
 
 int __dynamic_netdev_dbg(struct _ddebug *descriptor,
-                     const struct net_device *dev, const char *fmt, ...)
+                        const struct net_device *dev, const char *fmt, ...)
 {
        struct va_format vaf;
        va_list args;
        int res;
-       char buf[PREFIX_SIZE];
 
        BUG_ON(!descriptor);
        BUG_ON(!fmt);
 
        va_start(args, fmt);
+
        vaf.fmt = fmt;
        vaf.va = &args;
-       res = __netdev_printk(dynamic_emit_prefix(descriptor, buf), dev, &vaf);
+
+       if (dev && dev->dev.parent) {
+               char buf[PREFIX_SIZE];
+               char dict[128];
+               size_t dictlen;
+
+               dictlen = create_syslog_header(dev->dev.parent,
+                                              dict, sizeof(dict));
+
+               res = printk_emit(0, 7, dictlen ? dict : NULL, dictlen,
+                                 "%s%s %s: %s: %pV",
+                                 dynamic_emit_prefix(descriptor, buf),
+                                 dev_driver_string(dev->dev.parent),
+                                 dev_name(dev->dev.parent),
+                                 netdev_name(dev), &vaf);
+       } else if (dev) {
+               res = printk(KERN_DEBUG "%s: %pV", netdev_name(dev), &vaf);
+       } else {
+               res = printk(KERN_DEBUG "(NULL net_device): %pV", &vaf);
+       }
+
        va_end(args);
 
        return res;

diff --git a/net/core/dev.c b/net/core/dev.c
index d7fe32c..ac890f1 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6423,22 +6423,30 @@ const char *netdev_drivername(const struct net_device *dev)
        return empty;
 }
 
-int __netdev_printk(const char *level, const struct net_device *dev,
+static int __netdev_printk(const char *level, const struct net_device *dev,
                           struct va_format *vaf)
 {
        int r;
 
-       if (dev && dev->dev.parent)
-               r = dev_printk(level, dev->dev.parent, "%s: %pV",
-                              netdev_name(dev), vaf);
-       else if (dev)
+       if (dev && dev->dev.parent) {
+               char dict[128];
+               size_t dictlen = create_syslog_header(dev->dev.parent,
+                                                     dict, sizeof(dict));
+
+               r = printk_emit(0, level[1] - '0',
+                               dictlen ? dict : NULL, dictlen,
+                               "%s %s: %s: %pV",
+                               dev_driver_string(dev->dev.parent),
+                               dev_name(dev->dev.parent),
+                               netdev_name(dev), vaf);
+       } else if (dev) {
                r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
-       else
+       } else {
                r = printk("%s(NULL net_device): %pV", level, vaf);
+       }
 
        return r;
 }
-EXPORT_SYMBOL(__netdev_printk);
 
 int netdev_printk(const char *level, const struct net_device *dev,
                  const char *format, ...)
@@ -6453,6 +6461,7 @@ int netdev_printk(const char *level, const struct net_device *dev,
        vaf.va = &args;
 
        r = __netdev_printk(level, dev, &vaf);
+
        va_end(args);
 
        return r;
@@ -6472,6 +6481,7 @@ int func(const struct net_device *dev, const char *fmt, ...)      \
        vaf.va = &args;                                         \
                                                                \
        r = __netdev_printk(level, dev, &vaf);                  \
+                                                               \
        va_end(args);                                           \
                                                                \
        return r;                                               \