[TIMEWAIT]: Introduce inet_timewait_death_row

That groups all of the tables and variables associated to the TCP timewait
schedulling/recycling/killing code, that now can be isolated from the TCP
specific code and used by other transport protocols, such as DCCP.

Next changeset will move this code to net/ipv4/inet_timewait_sock.c

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 56 insertions, 1 deletions

diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index e00861b16696..a7e8052e2fbf 100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -19,13 +19,69 @@
 
 #include <linux/ip.h>
 #include <linux/list.h>
+#include <linux/timer.h>
 #include <linux/types.h>
+#include <linux/workqueue.h>
 
 #include <net/sock.h>
 #include <net/tcp_states.h>
 
 #include <asm/atomic.h>
 
+struct inet_hashinfo;
+
+#define INET_TWDR_RECYCLE_SLOTS_LOG     5
+#define INET_TWDR_RECYCLE_SLOTS         (1 << INET_TWDR_RECYCLE_SLOTS_LOG)
+
+/*
+ * If time > 4sec, it is "slow" path, no recycling is required,
+ * so that we select tick to get range about 4 seconds.
+ */
+#if HZ <= 16 || HZ > 4096
+# error Unsupported: HZ <= 16 or HZ > 4096
+#elif HZ <= 32
+# define INET_TWDR_RECYCLE_TICK (5 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+#elif HZ <= 64
+# define INET_TWDR_RECYCLE_TICK (6 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+#elif HZ <= 128
+# define INET_TWDR_RECYCLE_TICK (7 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+#elif HZ <= 256
+# define INET_TWDR_RECYCLE_TICK (8 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+#elif HZ <= 512
+# define INET_TWDR_RECYCLE_TICK (9 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+#elif HZ <= 1024
+# define INET_TWDR_RECYCLE_TICK (10 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+#elif HZ <= 2048
+# define INET_TWDR_RECYCLE_TICK (11 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+#else
+# define INET_TWDR_RECYCLE_TICK (12 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
+#endif
+
+/* TIME_WAIT reaping mechanism. */
+#define INET_TWDR_TWKILL_SLOTS  8 /* Please keep this a power of 2. */
+
+#define INET_TWDR_TWKILL_QUOTA 100
+
+struct inet_timewait_death_row {
+        /* Short-time timewait calendar */
+        int                     twcal_hand;
+        int                     twcal_jiffie;
+        struct timer_list       twcal_timer;
+        struct hlist_head       twcal_row[INET_TWDR_RECYCLE_SLOTS];
+
+        spinlock_t              death_lock;
+        int                     tw_count;
+        int                     period;
+        u32                     thread_slots;
+        struct work_struct      twkill_work;
+        struct timer_list       tw_timer;
+        int                     slot;
+        struct hlist_head       cells[INET_TWDR_TWKILL_SLOTS];
+        struct inet_hashinfo    *hashinfo;
+        int                     sysctl_tw_recycle;
+        int                     sysctl_max_tw_buckets;
+};
+
 #if (BITS_PER_LONG == 64)
 #define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 8
 #else
@@ -33,7 +89,6 @@
 #endif
 
 struct inet_bind_bucket;
-struct inet_hashinfo;
 
 /*
  * This is a TIME_WAIT sock. It works around the memory consumption