Remove semaphore map entry count "semmap" field and its tuning

option that is highly recommended to be adjusted in too much
documentation while doing nothing in FreeBSD since r2729 (rev 1.1).

ipcs(1) needs to be recompiled as it is accessing _KERNEL private
variables.

Reviewed by:	jhb (before comment change on linux code)
Sponsored by:	Sandvine Incorporated

7 files changed, 11 insertions, 18 deletions

diff --git a/sys/compat/linux/linux_ipc.c b/sys/compat/linux/linux_ipc.c
index 97cea53..a43de95 100644
--- a/sys/compat/linux/linux_ipc.c
+++ b/sys/compat/linux/linux_ipc.c
@@ -575,7 +575,15 @@ linux_semctl(struct thread *td, struct linux_semctl_args *args)
 		return (error);
 	case LINUX_IPC_INFO:
 	case LINUX_SEM_INFO:
-		bcopy(&seminfo, &linux_seminfo, sizeof(linux_seminfo) );
+		bcopy(&seminfo, &linux_seminfo.semmni, sizeof(linux_seminfo) -
+		    sizeof(linux_seminfo.semmap) );
+		/*
+		 * Linux does not use the semmap field either but populates it
+		 * with the defined value from SEMMAP, which really is redefined
+		 * to SEMMNS, which they define as SEMMNI * SEMMSL.
+		 * Try to simulate this returning our dynamic semmns value.
+		 */
+		linux_seminfo.semmap = linux_seminfo.semmns;
 /* XXX BSD equivalent?
 #define used_semids 10
 #define used_sems 10
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index 69378c6..dc44387 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -2833,9 +2833,6 @@ options 	VERBOSE_SYSINIT
 #####################################################################
 # SYSV IPC KERNEL PARAMETERS
 #
-# Maximum number of entries in a semaphore map.
-options 	SEMMAP=31
-
 # Maximum number of System V semaphores that can be used on the system at
 # one time.
 options 	SEMMNI=11
diff --git a/sys/conf/options b/sys/conf/options
index a77a54d..9f1ac80 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -164,7 +164,6 @@ MSGMNI		opt_sysvipc.h
 MSGSEG		opt_sysvipc.h
 MSGSSZ		opt_sysvipc.h
 MSGTQL		opt_sysvipc.h
-SEMMAP		opt_sysvipc.h
 SEMMNI		opt_sysvipc.h
 SEMMNS		opt_sysvipc.h
 SEMMNU		opt_sysvipc.h
diff --git a/sys/kern/sysv_sem.c b/sys/kern/sysv_sem.c
index 4bbe787..4a4c479 100644
--- a/sys/kern/sysv_sem.c
+++ b/sys/kern/sysv_sem.c
@@ -149,9 +149,6 @@ struct sem_undo {
 #endif
 
 /* shouldn't need tuning */
-#ifndef SEMMAP
-#define SEMMAP	30		/* # of entries in semaphore map */
-#endif
 #ifndef SEMMSL
 #define SEMMSL	SEMMNS		/* max # of semaphores per id */
 #endif
@@ -182,7 +179,6 @@ struct sem_undo {
  * semaphore info struct
  */
 struct seminfo seminfo = {
-                SEMMAP,         /* # of entries in semaphore map */
                 SEMMNI,         /* # of semaphore identifiers */
                 SEMMNS,         /* # of semaphores in system */
                 SEMMNU,         /* # of undo structures in system */
@@ -194,8 +190,6 @@ struct seminfo seminfo = {
                 SEMAEM          /* adjust on exit max value */
 };
 
-SYSCTL_INT(_kern_ipc, OID_AUTO, semmap, CTLFLAG_RW, &seminfo.semmap, 0,
-    "Number of entries in the semaphore map");
 SYSCTL_INT(_kern_ipc, OID_AUTO, semmni, CTLFLAG_RDTUN, &seminfo.semmni, 0,
     "Number of semaphore identifiers");
 SYSCTL_INT(_kern_ipc, OID_AUTO, semmns, CTLFLAG_RDTUN, &seminfo.semmns, 0,
@@ -255,7 +249,6 @@ seminit(void)
 {
 	int i, error;
 
-	TUNABLE_INT_FETCH("kern.ipc.semmap", &seminfo.semmap);
 	TUNABLE_INT_FETCH("kern.ipc.semmni", &seminfo.semmni);
 	TUNABLE_INT_FETCH("kern.ipc.semmns", &seminfo.semmns);
 	TUNABLE_INT_FETCH("kern.ipc.semmnu", &seminfo.semmnu);
diff --git a/sys/sys/sem.h b/sys/sys/sem.h
index cce28f0..f52bc0c 100644
--- a/sys/sys/sem.h
+++ b/sys/sys/sem.h
@@ -107,8 +107,7 @@ union semun {
  * semaphore info struct
  */
 struct seminfo {
-	int	semmap,		/* # of entries in semaphore map */
-		semmni,		/* # of semaphore identifiers */
+	int	semmni,		/* # of semaphore identifiers */
 		semmns,		/* # of semaphores in system */
 		semmnu,		/* # of undo structures in system */
 		semmsl,		/* max # of semaphores per id */
diff --git a/usr.bin/ipcs/ipc.c b/usr.bin/ipcs/ipc.c
index 14fbe1f..e0601dc 100644
--- a/usr.bin/ipcs/ipc.c
+++ b/usr.bin/ipcs/ipc.c
@@ -73,8 +73,7 @@ struct nlist symbols[] = {
 			X(shmseg, sizeof(u_long))			\
 			X(shmall, sizeof(u_long))
 
-#define	SEMINFO_XVEC	X(semmap, sizeof(int))				\
-			X(semmni, sizeof(int))				\
+#define	SEMINFO_XVEC	X(semmni, sizeof(int))				\
 			X(semmns, sizeof(int))				\
 			X(semmnu, sizeof(int))				\
 			X(semmsl, sizeof(int))				\
diff --git a/usr.bin/ipcs/ipcs.c b/usr.bin/ipcs/ipcs.c
index 3ddfa25..1d8e354 100644
--- a/usr.bin/ipcs/ipcs.c
+++ b/usr.bin/ipcs/ipcs.c
@@ -474,8 +474,6 @@ print_ksemtotal(struct seminfo seminfo)
 {
 
 	printf("seminfo:\n");
-	printf("\tsemmap: %12d\t(# of entries in semaphore map)\n",
-	    seminfo.semmap);
 	printf("\tsemmni: %12d\t(# of semaphore identifiers)\n",
 	    seminfo.semmni);
 	printf("\tsemmns: %12d\t(# of semaphores in system)\n",