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yaml --- r: 43891 b: refs/heads/master c: f049098 h: refs/heads/master i: 43889: a435103 43887: 1497bf9 v: v3
git-mirror · Dec 9, 2006 · d3455fa · d3455fa
1 parent 4cdf103
commit d3455fa
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Showing 2 changed files with 9 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 47bbec0282cce900f16a8dd6397260e076400edb
+refs/heads/master: f0490980a152958d25ce9762bfb296d8fd4c5512
diff --git a/trunk/include/linux/netdevice.h b/trunk/include/linux/netdevice.h
@@ -193,7 +193,14 @@ struct hh_cache
 {
 	struct hh_cache *hh_next;	/* Next entry			     */
 	atomic_t	hh_refcnt;	/* number of users                   */
-	__be16		hh_type;	/* protocol identifier, f.e ETH_P_IP
+/*
+ * We want hh_output, hh_len, hh_lock and hh_data be a in a separate
+ * cache line on SMP.
+ * They are mostly read, but hh_refcnt may be changed quite frequently,
+ * incurring cache line ping pongs.
+ */
+	__be16		hh_type ____cacheline_aligned_in_smp;
+					/* protocol identifier, f.e ETH_P_IP
                                          *  NOTE:  For VLANs, this will be the
                                          *  encapuslated type. --BLG
                                          */