Cache the result of getpagesize() so we only make one syscall.

Use getpagesize instead of CLBYTES.

2 files changed, 19 insertions, 16 deletions

diff --git a/lib/libc/gen/getpagesize.c b/lib/libc/gen/getpagesize.c
index d586cf6..556ff9e 100644
--- a/lib/libc/gen/getpagesize.c
+++ b/lib/libc/gen/getpagesize.c
@@ -38,16 +38,24 @@ static char sccsid[] = "@(#)getpagesize.c	8.1 (Berkeley) 6/4/93";
 #include <sys/param.h>
 #include <sys/sysctl.h>
 
+/*
+ * This is unlikely to change over the running time of any
+ * program, so we cache the result to save some syscalls.
+ */
+
 int
 getpagesize()
 {
-	int mib[2], value;
+	int mib[2]; 
+	static int value;
 	size_t size;
 
-	mib[0] = CTL_HW;
-	mib[1] = HW_PAGESIZE;
-	size = sizeof value;
-	if (sysctl(mib, 2, &value, &size, NULL, 0) == -1)
-		return (-1);
+	if (!value) {
+		mib[0] = CTL_HW;
+		mib[1] = HW_PAGESIZE;
+		size = sizeof value;
+		if (sysctl(mib, 2, &value, &size, NULL, 0) == -1)
+			return (-1);
+	}
 	return (value);
 }
diff --git a/lib/libc/gen/opendir.c b/lib/libc/gen/opendir.c
index 8cba9cf..a3db45b 100644
--- a/lib/libc/gen/opendir.c
+++ b/lib/libc/gen/opendir.c
@@ -79,18 +79,13 @@ opendir(name)
 	    (dirp = malloc(sizeof(DIR))) == NULL)
 		goto fail;
 	/*
-	 * If CLBYTES is an exact multiple of DIRBLKSIZ, use a CLBYTES
-	 * buffer that it cluster boundary aligned.
-	 * Hopefully this can be a big win someday by allowing page trades
-	 * to user space to be done by getdirentries()
+	 * Use the system page size if that is a multiple of DIRBLKSIZ
+	 * this could speed things up in some cases we hope
 	 */
-	if ((CLBYTES % DIRBLKSIZ) == 0) {
-		dirp->dd_buf = malloc(CLBYTES);
-		dirp->dd_len = CLBYTES;
-	} else {
-		dirp->dd_buf = malloc(DIRBLKSIZ);
+	dirp->dd_len = getpagesize();
+	if ((dirp->dd_len % DIRBLKSIZ) != 0) 
 		dirp->dd_len = DIRBLKSIZ;
-	}
+	dirp->dd_buf = malloc(dirp->dd_len);
 	if (dirp->dd_buf == NULL)
 		goto fail;
 	dirp->dd_fd = fd;