Add init_param3() to subr_param. This function is called

immediately after the kernel map has been sized, and is
the optimal place for the autosizing of memory allocations
which occur within the kernel map to occur.

Suggested by:	bde

2 files changed, 21 insertions, 26 deletions

diff --git a/sys/kern/kern_malloc.c b/sys/kern/kern_malloc.c
index 2d8daa3..a90d628 100644
--- a/sys/kern/kern_malloc.c
+++ b/sys/kern/kern_malloc.c
@@ -445,6 +445,11 @@ kmeminit(dummy)
 		vm_kmem_size = 2 * cnt.v_page_count * PAGE_SIZE;
 
 	/*
+	 * Tune settings based on the kernel map's size at this time.
+	 */
+	init_param3(vm_kmem_size / PAGE_SIZE);
+
+	/*
 	 * In mbuf_init(), we set up submaps for mbufs and clusters, in which
 	 * case we rounddown() (nmbufs * MSIZE) and (nmbclusters * MCLBYTES),
 	 * respectively. Mathematically, this means that what we do here may
diff --git a/sys/kern/subr_param.c b/sys/kern/subr_param.c
index 427a94a..0482aa9 100644
--- a/sys/kern/subr_param.c
+++ b/sys/kern/subr_param.c
@@ -135,23 +135,6 @@ void
 init_param2(long physpages)
 {
 
-	/* Kernel map size */
-	int kmempages, kmemtunable;
-	kmempages = VM_KMEM_SIZE / PAGE_SIZE;
-#if defined(VM_KMEM_SIZE_SCALE)
-        if ((physpages / VM_KMEM_SIZE_SCALE) > kmempages)
-                kmempages = (physpages / VM_KMEM_SIZE_SCALE);
-#endif   
-      
-#if defined(VM_KMEM_SIZE_MAX)
-        if (kmempages * PAGE_SIZE >= VM_KMEM_SIZE_MAX)
-                kmempages = VM_KMEM_SIZE_MAX / PAGE_SIZE;
-#endif
-	kmemtunable = 0;
-	TUNABLE_INT_FETCH("kern.vm.kmem.size", &kmemtunable);
-	if (kmemtunable != 0)
-		kmempages = kmemtunable / PAGE_SIZE;
-	kmempages = min(physpages, kmempages);
 	/* Base parameters */
 	maxusers = MAXUSERS;
 	TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
@@ -179,7 +162,23 @@ init_param2(long physpages)
 	TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
 	maxprocperuid = (maxproc * 9) / 10;
 	maxfilesperproc = (maxfiles * 9) / 10;
+	
+	/*
+	 * Cannot be changed after boot.
+	 */
+	nbuf = NBUF;
+	TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
+
+	ncallout = 16 + maxproc + maxfiles;
+	TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
+}
 
+/*
+ * Boot time overrides that are scaled against the kernel map
+ */
+void
+init_param3(long kmempages)
+{
 	/*
 	 * Limit number of pipes to a reasonable fraction of kmap entries,
 	 * pageable pipe memory usage to 2.5% of the kernel map, and wired
@@ -196,13 +195,4 @@ init_param2(long physpages)
 		maxpipekva = 512 * 1024;
 	if (maxpipekvawired < 512 * 1024)
 		maxpipekvawired = 512 * 1024;
-	
-	/*
-	 * Cannot be changed after boot.
-	 */
-	nbuf = NBUF;
-	TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
-
-	ncallout = 16 + maxproc + maxfiles;
-	TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
 }