svn commit: r343101 - head/sys/kern

[Gleb Smirnoff]

Author: glebius
Date: Wed Jan 16 20:20:38 2019
New Revision: 343101
URL: https://svnweb.freebsd.org/changeset/base/343101

Log:
  Fix mistake in r343030: move nswbuf calculation back to
  kern_vfs_bio_buffer_alloc(), because in init_param2() nbuf
  isn't really initialized yet.
  
  Pointed out by:	bde

Modified:
  head/sys/kern/subr_param.c
  head/sys/kern/vfs_bio.c

Modified: head/sys/kern/subr_param.c
==============================================================================
--- head/sys/kern/subr_param.c	Wed Jan 16 20:14:16 2019	(r343100)
+++ head/sys/kern/subr_param.c	Wed Jan 16 20:20:38 2019	(r343101)
@@ -291,10 +291,7 @@ init_param2(long physpages)
 	 * Physical buffers are pre-allocated buffers (struct buf) that
 	 * are used as temporary holders for I/O, such as paging I/O.
 	 */
-	nswbuf = min(nbuf / 4, 256);
 	TUNABLE_INT_FETCH("kern.nswbuf", &nswbuf);
-	if (nswbuf < NSWBUF_MIN)
-		nswbuf = NSWBUF_MIN;
 
 	/*
 	 * The default for maxpipekva is min(1/64 of the kernel address space,

Modified: head/sys/kern/vfs_bio.c
==============================================================================
--- head/sys/kern/vfs_bio.c	Wed Jan 16 20:14:16 2019	(r343100)
+++ head/sys/kern/vfs_bio.c	Wed Jan 16 20:20:38 2019	(r343101)
@@ -1124,6 +1124,12 @@ kern_vfs_bio_buffer_alloc(caddr_t v, long physmem_est)
 			nbuf = buf_sz / BKVASIZE;
 	}
 
+	if (nswbuf == 0) {
+		nswbuf = min(nbuf / 4, 256);
+		if (nswbuf < NSWBUF_MIN)
+			nswbuf = NSWBUF_MIN;
+	}
+
 	/*
 	 * Reserve space for the buffer cache buffers
 	 */