the uvm_km_putpage is calling into tangly uvm guts again on not pmap direct.

go back to something more like the previous design, and have the thread do
the heavy lifting.  solves vmmaplk panics.
ok deraadt oga thib
[and even simple diffs are hard to get perfect. help from mdempsky and deraadt]

diff --git a/sys/uvm/uvm_km.c b/sys/uvm/uvm_km.c
index 64b3f0b..aee736d 100644 (file)
--- a/sys/uvm/uvm_km.c
+++ b/sys/uvm/uvm_km.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: uvm_km.c,v 1.83 2010/07/02 23:12:38 thib Exp $        */
+/*     $OpenBSD: uvm_km.c,v 1.84 2010/07/15 00:14:17 tedu Exp $        */
 /*     $NetBSD: uvm_km.c,v 1.42 2001/01/14 02:10:01 thorpej Exp $      */
 
 /* 
@@ -707,6 +707,7 @@ struct uvm_km_pages uvm_km_pages;
 
 void uvm_km_createthread(void *);
 void uvm_km_thread(void *);
+struct uvm_km_free_page *uvm_km_doputpage(struct uvm_km_free_page *);
 
 /*
  * Allocate the initial reserve, and create the thread which will
@@ -768,34 +769,47 @@ uvm_km_thread(void *arg)
 {
        vaddr_t pg[16];
        int i;
+       int allocmore = 0;
+       struct uvm_km_free_page *fp = NULL;
 
        for (;;) {
                mtx_enter(&uvm_km_pages.mtx);
-               if (uvm_km_pages.free >= uvm_km_pages.lowat) {
+               if (uvm_km_pages.free >= uvm_km_pages.lowat &&
+                   uvm_km_pages.freelist == NULL) {
                        msleep(&uvm_km_pages.km_proc, &uvm_km_pages.mtx,
                            PVM, "kmalloc", 0);
                }
+               allocmore = uvm_km_pages.free < uvm_km_pages.lowat;
+               fp = uvm_km_pages.freelist;
+               uvm_km_pages.freelist = NULL;
+               uvm_km_pages.freelistlen = 0;
                mtx_leave(&uvm_km_pages.mtx);
 
-               for (i = 0; i < nitems(pg); i++) {
-                       pg[i] = (vaddr_t)uvm_km_kmemalloc(kernel_map, NULL,
-                           PAGE_SIZE, UVM_KMF_VALLOC);
-               }
+               if (allocmore) {
+                       for (i = 0; i < nitems(pg); i++) {
+                               pg[i] = (vaddr_t)uvm_km_kmemalloc(kernel_map,
+                                   NULL, PAGE_SIZE, UVM_KMF_VALLOC);
+                       }
+       
+                       mtx_enter(&uvm_km_pages.mtx);
+                       for (i = 0; i < nitems(pg); i++) {
+                               if (uvm_km_pages.free ==
+                                   nitems(uvm_km_pages.page))
+                                       break;
+                               else
+                                       uvm_km_pages.page[uvm_km_pages.free++]
+                                           = pg[i];
+                       }
+                       wakeup(&uvm_km_pages.free);
+                       mtx_leave(&uvm_km_pages.mtx);
 
-               mtx_enter(&uvm_km_pages.mtx);
-               for (i = 0; i < nitems(pg); i++) {
-                       if (uvm_km_pages.free == nitems(uvm_km_pages.page))
-                               break;
-                       else
-                               uvm_km_pages.page[uvm_km_pages.free++] = pg[i];
+                       /* Cleanup left-over pages (if any). */
+                       for (; i < nitems(pg); i++)
+                               uvm_km_free(kernel_map, pg[i], PAGE_SIZE);
+               }
+               while (fp) {
+                       fp = uvm_km_doputpage(fp);
                }
-
-               wakeup(&uvm_km_pages.free);
-               mtx_leave(&uvm_km_pages.mtx);
-
-               /* Cleanup left-over pages (if any). */
-               for (; i < nitems(pg); i++)
-                       uvm_km_free(kernel_map, pg[i], PAGE_SIZE);
        }
 }
 #endif
@@ -860,14 +874,35 @@ uvm_km_getpage_pla(int flags, int *slowdown, paddr_t low, paddr_t high,
 void
 uvm_km_putpage(void *v)
 {
+#ifdef __HAVE_PMAP_DIRECT
        vaddr_t va = (vaddr_t)v;
        struct vm_page *pg;
 
-#ifdef __HAVE_PMAP_DIRECT
        pg = pmap_unmap_direct(va);
+
+       uvm_pagefree(pg);
 #else  /* !__HAVE_PMAP_DIRECT */
+       struct uvm_km_free_page *fp = v;
+
+       mtx_enter(&uvm_km_pages.mtx);
+       fp->next = uvm_km_pages.freelist;
+       uvm_km_pages.freelist = fp;
+       if (uvm_km_pages.freelistlen++ > 16)
+               wakeup(&uvm_km_pages.km_proc);
+       mtx_leave(&uvm_km_pages.mtx);
+#endif /* !__HAVE_PMAP_DIRECT */
+}
+
+#ifndef __HAVE_PMAP_DIRECT
+struct uvm_km_free_page *
+uvm_km_doputpage(struct uvm_km_free_page *fp)
+{
+       vaddr_t va = (vaddr_t)fp;
+       struct vm_page *pg;
        int     freeva = 1;
        paddr_t pa;
+       struct uvm_km_free_page *nextfp = fp->next;
+
        if (!pmap_extract(pmap_kernel(), va, &pa))
                panic("lost pa");
        pg = PHYS_TO_VM_PAGE(pa);
@@ -886,7 +921,8 @@ uvm_km_putpage(void *v)
 
        if (freeva)
                uvm_km_free(kernel_map, va, PAGE_SIZE);
-#endif /* !__HAVE_PMAP_DIRECT */
 
        uvm_pagefree(pg);
+       return (nextfp);
 }
+#endif /* !__HAVE_PMAP_DIRECT */

diff --git a/sys/uvm/uvm_km.h b/sys/uvm/uvm_km.h
index b14f2e6..76a2ce9 100644 (file)
--- a/sys/uvm/uvm_km.h
+++ b/sys/uvm/uvm_km.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: uvm_km.h,v 1.10 2010/06/28 04:20:29 miod Exp $        */
+/*     $OpenBSD: uvm_km.h,v 1.11 2010/07/15 00:14:17 tedu Exp $        */
 /*     $NetBSD: uvm_km.h,v 1.9 1999/06/21 17:25:11 thorpej Exp $       */
 
 /*
@@ -58,6 +58,9 @@ void uvm_km_pgremove_intrsafe(vaddr_t, vaddr_t);
 #define UVM_KM_PAGES_LOWAT_MAX (2048)
 #define UVM_KM_PAGES_HIWAT_MAX (4 * UVM_KM_PAGES_LOWAT_MAX)
 
+struct uvm_km_free_page {
+       struct uvm_km_free_page *next;
+};
 struct uvm_km_pages {
        struct  mutex mtx;
 
@@ -69,6 +72,9 @@ struct uvm_km_pages {
        int     free;
        vaddr_t page[UVM_KM_PAGES_HIWAT_MAX];
 
+       struct uvm_km_free_page *freelist;
+       int freelistlen;
+
        struct  proc *km_proc;
 };