svn commit: r343147 - head/sys/x86/x86

[Konstantin Belousov]

Author: kib
Date: Fri Jan 18 13:43:11 2019
New Revision: 343147
URL: https://svnweb.freebsd.org/changeset/base/343147

Log:
  i386/PAE busdma: allow more bounce pages.
  
  If i386 has more than 4G of memory, allow the same number of busdma
  bounce pages as for amd64.  In fact, in this case bouncing sometimes
  is much heavier than on amd64.
  
  Reviewed by:	markj
  Tested by:	pho
  Sponsored by:	The FreeBSD Foundation
  MFC after:	2 weeks
  Differential revision:	https://reviews.freebsd.org/D18854

Modified:
  head/sys/x86/x86/busdma_bounce.c

Modified: head/sys/x86/x86/busdma_bounce.c
==============================================================================
--- head/sys/x86/x86/busdma_bounce.c	Fri Jan 18 13:38:56 2019	(r343146)
+++ head/sys/x86/x86/busdma_bounce.c	Fri Jan 18 13:43:11 2019	(r343147)
@@ -57,7 +57,7 @@ __FBSDID("$FreeBSD$");
 #include <x86/include/busdma_impl.h>
 
 #ifdef __i386__
-#define MAX_BPAGES 512
+#define MAX_BPAGES (Maxmem > atop(0x100000000ULL) ? 8192 : 512)
 #else
 #define MAX_BPAGES 8192
 #endif