[src/trunk]: src/sys/external/bsd/drm2/linux Use direct map if available in l...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/43215a144361
branches:  trunk
changeset: 802010:43215a144361
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Wed Aug 27 16:41:50 2014 +0000

description:
Use direct map if available in linux_kmap.

Yields 20% increase in glxgears framerate.

diffstat:

 sys/external/bsd/drm2/linux/linux_kmap.c |  46 ++++++++++++++++++++++++++-----
 1 files changed, 38 insertions(+), 8 deletions(-)

diffs (101 lines):

diff -r 253adecd2628 -r 43215a144361 sys/external/bsd/drm2/linux/linux_kmap.c
--- a/sys/external/bsd/drm2/linux/linux_kmap.c  Wed Aug 27 16:19:54 2014 +0000
+++ b/sys/external/bsd/drm2/linux/linux_kmap.c  Wed Aug 27 16:41:50 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: linux_kmap.c,v 1.9 2014/08/27 16:19:54 riastradh Exp $ */
+/*     $NetBSD: linux_kmap.c,v 1.10 2014/08/27 16:41:50 riastradh Exp $        */
 
 /*-
  * Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -30,13 +30,17 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_kmap.c,v 1.9 2014/08/27 16:19:54 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_kmap.c,v 1.10 2014/08/27 16:41:50 riastradh Exp $");
 
 #include <sys/types.h>
 #include <sys/kmem.h>
 #include <sys/mutex.h>
 #include <sys/rbtree.h>
 
+#ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
+#include <dev/mm.h>
+#endif
+
 #include <uvm/uvm_extern.h>
 
 #include <linux/highmem.h>
@@ -48,12 +52,6 @@
  * use at a time.
  */
 
-/*
- * XXX Use direct-mapped physical pages where available, e.g. amd64.
- *
- * XXX ...or add an abstraction to uvm for this.  (uvm_emap?)
- */
-
 static kmutex_t linux_kmap_atomic_lock;
 static vaddr_t linux_kmap_atomic_vaddr;
 
@@ -146,6 +144,11 @@
        const paddr_t paddr = uvm_vm_page_to_phys(&page->p_vmp);
        vaddr_t vaddr;
 
+#ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
+       if (mm_md_direct_mapped_phys(paddr, &vaddr))
+               return (void *)vaddr;
+#endif
+
        mutex_spin_enter(&linux_kmap_atomic_lock);
        KASSERT(linux_kmap_atomic_vaddr != 0);
        KASSERT(!pmap_extract(pmap_kernel(), linux_kmap_atomic_vaddr, NULL));
@@ -161,6 +164,19 @@
 {
        const vaddr_t vaddr = (vaddr_t)addr;
 
+#ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
+    {
+       paddr_t paddr;
+       vaddr_t vaddr1;
+       bool ok __diagused;
+
+       ok = pmap_extract(pmap_kernel(), vaddr, &paddr);
+       KASSERT(ok);
+       if (mm_md_direct_mapped_phys(paddr, &vaddr1) && vaddr1 == vaddr)
+               return;
+    }
+#endif
+
        KASSERT(mutex_owned(&linux_kmap_atomic_lock));
        KASSERT(linux_kmap_atomic_vaddr == vaddr);
        KASSERT(pmap_extract(pmap_kernel(), vaddr, NULL));
@@ -179,6 +195,11 @@
 
        ASSERT_SLEEPABLE();
 
+#ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
+       if (mm_md_direct_mapped_phys(paddr, &vaddr))
+               return (void *)vaddr;
+#endif
+
        vaddr = uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
            (UVM_KMF_VAONLY | UVM_KMF_WAITVA));
        KASSERT(vaddr != 0);
@@ -208,6 +229,15 @@
 
        ASSERT_SLEEPABLE();
 
+#ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
+    {
+       vaddr_t vaddr1;
+
+       if (mm_md_direct_mapped_phys(paddr, &vaddr1))
+               return;
+    }
+#endif
+
        mutex_enter(&linux_kmap_lock);
        struct linux_kmap_entry *const lke =
            rb_tree_find_node(&linux_kmap_entries, &paddr);