inpcb: retire the inpcbinfo list lock

With the SMR locking of inpcbs the use of this lock reduced down to the
global list and generation number.  It was used only on an inpcb creation
and destruction.  Use the inpcbinfo hash lock for this purpose.

Reviewed by:		pouria, rrs, markj
Differential Revision:	https://reviews.freebsd.org/D55966

sys/netinet/in_pcb.c

@@ -558,7 +558,6 @@ in_pcbinfo_init(struct inpcbinfo *pcbinfo, struct inpcbstorage *pcbstor,
 		.head = HASH_HEAD_CK_LIST,
 	};
 
-	mtx_init(&pcbinfo->ipi_lock, pcbstor->ips_infolock_name, NULL, MTX_DEF);
 	mtx_init(&pcbinfo->ipi_hash_lock, pcbstor->ips_hashlock_name,
 	    NULL, MTX_DEF);
 #ifdef VIMAGE
@@ -602,7 +601,6 @@ in_pcbinfo_destroy(struct inpcbinfo *pcbinfo)
 	hashfree(pcbinfo->ipi_porthashbase, &ha);
 	hashfree(pcbinfo->ipi_lbgrouphashbase, &ha);
 	mtx_destroy(&pcbinfo->ipi_hash_lock);
-	mtx_destroy(&pcbinfo->ipi_lock);
 }
 
 /*
@@ -697,11 +695,11 @@ in_pcballoc(struct socket *so, struct inpcbinfo *pcbinfo)
 	inp->inp_route.ro_flags = RT_LLE_CACHE;
 	refcount_init(&inp->inp_refcount, 1);   /* Reference from socket. */
 	INP_WLOCK(inp);
-	INP_INFO_WLOCK(pcbinfo);
+	INP_HASH_WLOCK(pcbinfo);
 	pcbinfo->ipi_count++;
 	inp->inp_gencnt = ++pcbinfo->ipi_gencnt;
 	CK_LIST_INSERT_HEAD(&pcbinfo->ipi_listhead, inp, inp_list);
-	INP_INFO_WUNLOCK(pcbinfo);
+	INP_HASH_WUNLOCK(pcbinfo);
 	so->so_pcb = inp;
 
 	return (0);
@@ -1799,13 +1797,13 @@ in_pcbfree(struct inpcb *inp)
 	 * from the hash without acquiring inpcb lock, they rely on the hash
 	 * lock, thus in_pcbremhash() should be the first action.
 	 */
+	INP_HASH_WLOCK(pcbinfo);
 	if (inp->inp_flags & INP_INHASHLIST)
-		in_pcbremhash(inp);
-	INP_INFO_WLOCK(pcbinfo);
+		in_pcbremhash_locked(inp);
 	inp->inp_gencnt = ++pcbinfo->ipi_gencnt;
 	pcbinfo->ipi_count--;
 	CK_LIST_REMOVE(inp, inp_list);
-	INP_INFO_WUNLOCK(pcbinfo);
+	INP_HASH_WUNLOCK(pcbinfo);
 
 #ifdef RATELIMIT
 	if (inp->inp_snd_tag != NULL)

sys/netinet/in_pcb.h

@@ -422,30 +422,23 @@ struct inpcb {
  * IPv4 and IPv6.
  *
  * The pcbs are protected with SMR section and thus all lists in inpcbinfo
- * are CK-lists.  Locking is required to insert a pcb into database. Two
- * locks are provided: one for the hash and one for the global list of pcbs,
- * as well as overall count and generation count.
+ * are CK-lists.  Locking is required to insert a pcb into database.
  *
  * Locking key:
  *
  * (c) Constant or nearly constant after initialisation
  * (e) Protected by SMR section
- * (g) Locked by ipi_lock
  * (h) Locked by ipi_hash_lock
  */
 struct inpcbinfo {
-	/*
-	 * Global lock protecting inpcb list modification
-	 */
-	struct mtx		 ipi_lock;
-	struct inpcbhead	 ipi_listhead;		/* (r:e/w:g) */
-	u_int			 ipi_count;		/* (g) */
+	struct inpcbhead	 ipi_listhead;		/* (r:e/w:h) */
+	u_int			 ipi_count;		/* (h) */
 
 	/*
 	 * Generation count -- incremented each time a connection is allocated
 	 * or freed.
 	 */
-	u_quad_t		 ipi_gencnt;		/* (g) */
+	u_quad_t		 ipi_gencnt;		/* (h) */
 
 	/*
 	 * Fields associated with port lookup and allocation.
@@ -498,11 +491,10 @@ struct inpcbstorage {
 	uma_init	ips_pcbinit;
 	size_t		ips_size;
 	const char *	ips_zone_name;
-	const char *	ips_infolock_name;
 	const char *	ips_hashlock_name;
 };
 
-#define INPCBSTORAGE_DEFINE(prot, ppcb, lname, zname, iname, hname)	\
+#define INPCBSTORAGE_DEFINE(prot, ppcb, lname, zname, hname)		\
 static int								\
 prot##_inpcb_init(void *mem, int size __unused, int flags __unused)	\
 {									\
@@ -515,7 +507,6 @@ static struct inpcbstorage prot = {					\
 	.ips_size = sizeof(struct ppcb),				\
 	.ips_pcbinit = prot##_inpcb_init,				\
 	.ips_zone_name = zname,						\
-	.ips_infolock_name = iname,					\
 	.ips_hashlock_name = hname,					\
 };									\
 SYSINIT(prot##_inpcbstorage_init, SI_SUB_PROTO_DOMAIN,			\
@@ -564,15 +555,6 @@ struct socket *
 void 	inp_4tuple_get(struct inpcb *inp, uint32_t *laddr, uint16_t *lp,
 		uint32_t *faddr, uint16_t *fp);
 
-#define INP_INFO_WLOCK(ipi)	mtx_lock(&(ipi)->ipi_lock)
-#define INP_INFO_WLOCKED(ipi)	mtx_owned(&(ipi)->ipi_lock)
-#define INP_INFO_WUNLOCK(ipi)	mtx_unlock(&(ipi)->ipi_lock)
-#define	INP_INFO_LOCK_ASSERT(ipi)	MPASS(SMR_ENTERED((ipi)->ipi_smr) || \
-					mtx_owned(&(ipi)->ipi_lock))
-#define INP_INFO_WLOCK_ASSERT(ipi)	mtx_assert(&(ipi)->ipi_lock, MA_OWNED)
-#define INP_INFO_WUNLOCK_ASSERT(ipi)	\
-				mtx_assert(&(ipi)->ipi_lock, MA_NOTOWNED)
-
 #define	INP_HASH_WLOCK(ipi)		mtx_lock(&(ipi)->ipi_hash_lock)
 #define	INP_HASH_WUNLOCK(ipi)		mtx_unlock(&(ipi)->ipi_hash_lock)
 #define	INP_HASH_LOCK_ASSERT(ipi)	MPASS(SMR_ENTERED((ipi)->ipi_smr) || \

sys/netinet/raw_ip.c

@@ -181,7 +181,7 @@ rip_delhash(struct inpcb *inp)
 }
 #endif /* INET */
 
-INPCBSTORAGE_DEFINE(ripcbstor, inpcb, "rawinp", "ripcb", "rip", "riphash");
+INPCBSTORAGE_DEFINE(ripcbstor, inpcb, "rawinp", "ripcb", "riphash");
 
 static void
 rip_init(void *arg __unused)

sys/netinet/tcp_subr.c

@@ -1140,7 +1140,7 @@ static struct mtx isn_mtx;
 #define	ISN_LOCK()	mtx_lock(&isn_mtx)
 #define	ISN_UNLOCK()	mtx_unlock(&isn_mtx)
 
-INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcp", "tcphash");
+INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcphash");
 
 /*
  * Take a value and get the next power of 2 that doesn't overflow.

sys/netinet/udp_usrreq.c

@@ -165,9 +165,9 @@ VNET_PCPUSTAT_SYSUNINIT(udpstat);
 static void	udp_detach(struct socket *so);
 #endif
 
-INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udp", "udphash");
+INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udphash");
 INPCBSTORAGE_DEFINE(udplitecbstor, udpcb, "udpliteinp", "udplite_inpcb",
-    "udplite", "udplitehash");
+    "udplitehash");
 
 static void
 udp_vnet_init(void *arg __unused)