[PATCH] Improve endian conversion in umac.c

[rapier]

On 3/11/22 12:56 AM, Rolf Eike Beer wrote:
>> + * Forward declaration of the functions in order to maintain
>> + * the attributes.
>> + * Chris Rapier <rapier at psc.edu> 2022-03-09 */
>> +
>> +static u_int32_t umac_get_u32_le(const void *)
>> +    __attribute__((__bounded__(__minbytes__, 1, 4)));
>> +
>> +static u_int32_t
>> +umac_get_u32_le(const void *vp)
> 
> You should be able to combine this into one statement if you write:
> 
> static __attribute__((__bounded__(__minbytes__, 1, 4)))
> u_int32_t umac_get_u32_le(const void *)
> {

Excellent! Thank you. I had it in one statement before but the order was 
wrong so it kept throwing errors.



diff --git a/misc.c b/misc.c
index 0134d694..20a2a186 100644
--- a/misc.c
+++ b/misc.c
@@ -1533,20 +1533,6 @@ get_u32(const void *vp)
  	return (v);
  }

-u_int32_t
-get_u32_le(const void *vp)
-{
-	const u_char *p = (const u_char *)vp;
-	u_int32_t v;
-
-	v  = (u_int32_t)p[0];
-	v |= (u_int32_t)p[1] << 8;
-	v |= (u_int32_t)p[2] << 16;
-	v |= (u_int32_t)p[3] << 24;
-
-	return (v);
-}
-
  u_int16_t
  get_u16(const void *vp)
  {
@@ -1585,17 +1571,6 @@ put_u32(void *vp, u_int32_t v)
  	p[3] = (u_char)v & 0xff;
  }

-void
-put_u32_le(void *vp, u_int32_t v)
-{
-	u_char *p = (u_char *)vp;
-
-	p[0] = (u_char)v & 0xff;
-	p[1] = (u_char)(v >> 8) & 0xff;
-	p[2] = (u_char)(v >> 16) & 0xff;
-	p[3] = (u_char)(v >> 24) & 0xff;
-}
-
  void
  put_u16(void *vp, u_int16_t v)
  {
diff --git a/misc.h b/misc.h
index 2e2dca54..b0c64270 100644
--- a/misc.h
+++ b/misc.h
@@ -154,12 +154,6 @@ void		put_u32(void *, u_int32_t)
  void		put_u16(void *, u_int16_t)
      __attribute__((__bounded__( __minbytes__, 1, 2)));

-/* Little-endian store/load, used by umac.c */
-u_int32_t	get_u32_le(const void *)
-    __attribute__((__bounded__(__minbytes__, 1, 4)));
-void		put_u32_le(void *, u_int32_t)
-    __attribute__((__bounded__(__minbytes__, 1, 4)));
-
  struct bwlimit {
  	size_t buflen;
  	u_int64_t rate;		/* desired rate in kbit/s */
diff --git a/umac.c b/umac.c
index e5ec19f0..81040b97 100644
--- a/umac.c
+++ b/umac.c
@@ -134,15 +134,48 @@ typedef unsigned int	UWORD;  /* Register */
  /* --- Endian Conversion --- Forcing assembly on some platforms 
     */
  /* 
---------------------------------------------------------------------- */

+
+/* Using local statically defined versions of the get/put functions
+ * found in misc.c allows them to be inlined. This improves throughput
+ * performance by 10% to 15% on well connected (10Gb/s+) systems.
+ * Chris Rapier <rapier at psc.edu> 2022-03-09 */
+
+static  __attribute__((__bounded__(__minbytes__, 1, 4)))
+u_int32_t umac_get_u32_le(const void *vp)
+{
+        const u_char *p = (const u_char *)vp;
+        u_int32_t v;
+
+        v  = (u_int32_t)p[0];
+        v |= (u_int32_t)p[1] << 8;
+        v |= (u_int32_t)p[2] << 16;
+        v |= (u_int32_t)p[3] << 24;
+
+        return (v);
+}
+
+#if (! __LITTLE_ENDIAN__) /* compile time warning thrown otherwise */
+static __attribute__((__bounded__(__minbytes__, 1, 4)));
+void umac_put_u32_le(void *vp, u_int32_t v)
+{
+        u_char *p = (u_char *)vp;
+
+        p[0] = (u_char)v & 0xff;
+        p[1] = (u_char)(v >> 8) & 0xff;
+        p[2] = (u_char)(v >> 16) & 0xff;
+        p[3] = (u_char)(v >> 24) & 0xff;
+}
+#endif
+
  #if (__LITTLE_ENDIAN__)
  #define LOAD_UINT32_REVERSED(p)		get_u32(p)
  #define STORE_UINT32_REVERSED(p,v)	put_u32(p,v)
  #else
-#define LOAD_UINT32_REVERSED(p)		get_u32_le(p)
-#define STORE_UINT32_REVERSED(p,v)	put_u32_le(p,v)
+#define LOAD_UINT32_REVERSED(p)		umac_get_u32_le(p)
+#define STORE_UINT32_REVERSED(p,v)	umac_put_u32_le(p,v)
  #endif

-#define LOAD_UINT32_LITTLE(p)		(get_u32_le(p))
+#define LOAD_UINT32_LITTLE(p)		(umac_get_u32_le(p))
  #define STORE_UINT32_BIG(p,v)		put_u32(p, v)

  /* 
---------------------------------------------------------------------- */