add definition for ability to produce a backtrace

[unix-history] / usr / src / sys / kern / kern_malloc.c

diff --git a/usr/src/sys/kern/kern_malloc.c b/usr/src/sys/kern/kern_malloc.c
index 8edc50d..76d5e1a 100644 (file)
--- a/usr/src/sys/kern/kern_malloc.c
+++ b/usr/src/sys/kern/kern_malloc.c
@@ -1,103 +1,133 @@
 /*
 /*

- * Copyright (c) 1987 Regents of the University of California.
- * All rights reserved.
+ * Copyright (c) 1987, 1991, 1993
+ *     The Regents of the University of California.  All rights reserved.

  *
  * %sccs.include.redist.c%
  *
  *
  * %sccs.include.redist.c%
  *

- *     @(#)kern_malloc.c       7.18 (Berkeley) %G%
+ *     @(#)kern_malloc.c       8.3 (Berkeley) %G%

  */
 
  */
 

-#include "param.h"
-#include "vm.h"
-#include "cmap.h"
-#include "time.h"
-#include "proc.h"
-#include "map.h"
-#include "kernel.h"
-#include "malloc.h"
+#include <sys/param.h>
+#include <sys/proc.h>
+#include <sys/map.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>

 
 

-#include "machine/pte.h"
+#include <vm/vm.h>
+#include <vm/vm_kern.h>

 
 struct kmembuckets bucket[MINBUCKET + 16];
 struct kmemstats kmemstats[M_LAST];
 struct kmemusage *kmemusage;
 
 struct kmembuckets bucket[MINBUCKET + 16];
 struct kmemstats kmemstats[M_LAST];
 struct kmemusage *kmemusage;

-long wantkmemmap;
+char *memname[] = INITKMEMNAMES;
+char *kmembase, *kmemlimit;
+char *memname[] = INITKMEMNAMES;

 long malloc_reentered;
 #define IN { if (malloc_reentered) panic("malloc reentered");\
                        else malloc_reentered = 1;}
 #define OUT (malloc_reentered = 0)
 
 long malloc_reentered;
 #define IN { if (malloc_reentered) panic("malloc reentered");\
                        else malloc_reentered = 1;}
 #define OUT (malloc_reentered = 0)
 

+#ifdef DIAGNOSTIC
+/*
+ * This structure provides a set of masks to catch unaligned frees.
+ */
+long addrmask[] = { 0,
+       0x00000001, 0x00000003, 0x00000007, 0x0000000f,
+       0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff,
+       0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff,
+       0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff,
+};
+
+/*
+ * The WEIRD_ADDR is used as known text to copy into free objects so
+ * that modifications after frees can be detected.
+ */
+#define WEIRD_ADDR     0xdeadbeef
+#define MAX_COPY       32
+
+/*
+ * Normally the first word of the structure is used to hold the list
+ * pointer for free objects. However, when running with diagnostics,
+ * we use the third and fourth fields, so as to catch modifications
+ * in the most commonly trashed first two words.
+ */
+struct freelist {
+       long    spare0;
+       short   type;
+       long    spare1;
+       caddr_t next;
+};
+#else /* !DIAGNOSTIC */
+struct freelist {
+       caddr_t next;
+};
+#endif /* DIAGNOSTIC */
+
+struct uselist {
+       struct  uselist *next;
+       caddr_t mem;
+       long    size;
+       long    type;
+} *listhd;
+

 /*
  * Allocate a block of memory
  */
 /*
  * Allocate a block of memory
  */

-qaddr_t
+void *

 malloc(size, type, flags)
        unsigned long size;
        int type, flags;
 {
        register struct kmembuckets *kbp;
        register struct kmemusage *kup;
 malloc(size, type, flags)
        unsigned long size;
        int type, flags;
 {
        register struct kmembuckets *kbp;
        register struct kmemusage *kup;

-       long indx, npg, alloc, allocsize;
+       register struct freelist *freep;
+       long indx, npg, allocsize;

        int s;
        int s;

-       caddr_t va, cp;
+       caddr_t va, cp, rp;

 #ifdef KMEMSTATS
        register struct kmemstats *ksp = &kmemstats[type];
 
 #ifdef KMEMSTATS
        register struct kmemstats *ksp = &kmemstats[type];
 

+#ifdef DIAGNOSTIC

        if (((unsigned long)type) > M_LAST)
                panic("malloc - bogus type");
        if (((unsigned long)type) > M_LAST)
                panic("malloc - bogus type");

-#endif
-
+       if (type == M_NAMEI)
+               curproc->p_spare[0]++;

        indx = BUCKETINDX(size);
        kbp = &bucket[indx];
        s = splimp();
        IN;
        indx = BUCKETINDX(size);
        kbp = &bucket[indx];
        s = splimp();
        IN;

-again:

 #ifdef KMEMSTATS
        while (ksp->ks_memuse >= ksp->ks_limit) {
                if (flags & M_NOWAIT) {
                        OUT;
                        splx(s);
 #ifdef KMEMSTATS
        while (ksp->ks_memuse >= ksp->ks_limit) {
                if (flags & M_NOWAIT) {
                        OUT;
                        splx(s);

-                       return (0);
+                       return ((void *) NULL);

                }
                if (ksp->ks_limblocks < 65535)
                        ksp->ks_limblocks++;
                OUT;
                }
                if (ksp->ks_limblocks < 65535)
                        ksp->ks_limblocks++;
                OUT;

-               sleep((caddr_t)ksp, PSWP+2);
+               tsleep((caddr_t)ksp, PSWP+2, memname[type], 0);

                IN;
        }
                IN;
        }

+       ksp->ks_size |= 1 << indx;
+#endif
+#ifdef DIAGNOSTIC
+       copysize = 1 << indx < MAX_COPY ? 1 << indx : MAX_COPY;

 #endif
        if (kbp->kb_next == NULL) {
 #endif
        if (kbp->kb_next == NULL) {

+               kbp->kb_last = NULL;

                if (size > MAXALLOCSAVE)
                        allocsize = roundup(size, CLBYTES);
                else
                        allocsize = 1 << indx;
                npg = clrnd(btoc(allocsize));
                if (size > MAXALLOCSAVE)
                        allocsize = roundup(size, CLBYTES);
                else
                        allocsize = 1 << indx;
                npg = clrnd(btoc(allocsize));

-               if ((flags & M_NOWAIT) && freemem < npg) {
+               va = (caddr_t) kmem_malloc(kmem_map, (vm_size_t)ctob(npg),
+                                          !(flags & M_NOWAIT));
+               if (va == NULL) {

                        OUT;
                        splx(s);
                        OUT;
                        splx(s);

-                       return (0);
-               }
-               alloc = rmalloc(kmemmap, npg);
-               if (alloc == 0) {
-                       if (flags & M_NOWAIT) {
-                               OUT;
-                               splx(s);
-                               return (0);
-                       }
-#ifdef KMEMSTATS
-                       if (ksp->ks_mapblocks < 65535)
-                               ksp->ks_mapblocks++;
-#endif
-                       wantkmemmap++;
-                       OUT;
-                       sleep((caddr_t)&wantkmemmap, PSWP+2);
-                       IN;
-                       goto again;
+                       return ((void *) NULL);

                }
                }

-               alloc -= CLSIZE;                /* convert to base 0 */
-               (void) vmemall(&kmempt[alloc], (int)npg, &proc[0], CSYS);
-               va = (caddr_t) kmemxtob(alloc);
-               vmaccess(&kmempt[alloc], va, (int)npg);

 #ifdef KMEMSTATS
                kbp->kb_total += kbp->kb_elmpercl;
 #endif
 #ifdef KMEMSTATS
                kbp->kb_total += kbp->kb_elmpercl;
 #endif


@@ -116,9 +146,15 @@ again:
                kup->ku_freecnt = kbp->kb_elmpercl;
                kbp->kb_totalfree += kbp->kb_elmpercl;
 #endif
                kup->ku_freecnt = kbp->kb_elmpercl;
                kbp->kb_totalfree += kbp->kb_elmpercl;
 #endif

-               kbp->kb_next = va + (npg * NBPG) - allocsize;
+               /*
+                * Just in case we blocked while allocating memory,
+                * and someone else also allocated memory for this
+                * bucket, don't assume the list is still empty.
+                */
+               savedlist = kbp->kb_next;
+               rp = kbp->kb_next; /* returned while blocked in vmemall */

                for (cp = kbp->kb_next; cp >= va; cp -= allocsize) {
                for (cp = kbp->kb_next; cp >= va; cp -= allocsize) {

-                       ((caddr_t *)cp)[2] = (cp > va ? cp - allocsize : NULL);
+                       ((caddr_t *)cp)[2] = (cp > va ? cp - allocsize : rp);

                        if (indx == 7) {
                                long *lp = (long *)cp;
                                lp[0] = lp[1] = lp[3] = lp[4] = -1;
                        if (indx == 7) {
                                long *lp = (long *)cp;
                                lp[0] = lp[1] = lp[3] = lp[4] = -1;


@@ -150,41 +186,102 @@ out:
 #else
 out:
 #endif
 #else
 out:
 #endif

+       if (size > 64 && size <= 128) {
+               mlp = (struct uselist *)malloc(sizeof(*mlp), M_TEMP, M_WAITOK);
+               mlp->type = type;
+               mlp->size = size;
+               mlp->mem = va;
+               mlp->next = listhd;
+               listhd = mlp;
+       }

        OUT;
        splx(s);
        OUT;
        splx(s);

-       return ((qaddr_t)va);
+       return ((void *) va);

 }
 
 }
 

+#ifdef DIAGNOSTIC
+long addrmask[] = { 0x00000000,
+       0x00000001, 0x00000003, 0x00000007, 0x0000000f,
+       0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff,
+       0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff,
+       0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff,
+};
+#endif /* DIAGNOSTIC */
+

 /*
  * Free a block of memory allocated by malloc.
  */
 void
 free(addr, type)
 /*
  * Free a block of memory allocated by malloc.
  */
 void
 free(addr, type)

-       caddr_t addr;
+       void *addr;

        int type;
 {
        register struct kmembuckets *kbp;
        register struct kmemusage *kup;
        int type;
 {
        register struct kmembuckets *kbp;
        register struct kmemusage *kup;

-       long alloc, size;
+       register struct freelist *freep;
+       long size;

        int s;
        int s;

+#ifdef DIAGNOSTIC
+       caddr_t cp;
+       long *end, *lp, alloc, copysize;
+#endif

 #ifdef KMEMSTATS
        register struct kmemstats *ksp = &kmemstats[type];
 #endif
 
        kup = btokup(addr);
 #ifdef KMEMSTATS
        register struct kmemstats *ksp = &kmemstats[type];
 #endif
 
        kup = btokup(addr);

+       size = 1 << kup->ku_indx;
+#ifdef DIAGNOSTIC
+       if (size > NBPG * CLSIZE)
+               alloc = addrmask[BUCKETINDX(NBPG * CLSIZE)];
+       else
+               alloc = addrmask[kup->ku_indx];
+       if (((u_long)addr & alloc) != 0) {
+               printf("free: unaligned addr 0x%x, size %d, type %d, mask %d\n",
+                       addr, size, type, alloc);
+               panic("free: unaligned addr");
+       }
+#endif /* DIAGNOSTIC */
+       size = 1 << kup->ku_indx;

        kbp = &bucket[kup->ku_indx];
        s = splimp();
        kbp = &bucket[kup->ku_indx];
        s = splimp();

+       if (size == 128) {
+               struct uselist *mlp, *pmlp;
+
+               mlp = listhd;
+               if (mlp->mem == addr)
+                       listhd = mlp->next;
+               else for (pmlp = mlp, mlp = mlp->next ; mlp; mlp = mlp->next) {
+                       if (mlp->mem == addr) {
+                               pmlp->next = mlp->next;
+                               break;
+                       }
+                       pmlp = mlp;
+               }
+               if (mlp == NULL)
+                       printf("free: lost type %s size %d\n", memname[type],
+                           size);
+               else
+                       free(mlp, M_TEMP);
+       }
+#ifdef DIAGNOSTIC
+       /*
+        * Check for returns of data that do not point to the
+        * beginning of the allocation.
+        */
+       if (type == M_NAMEI)
+               curproc->p_spare[0]--;
+       if (size > NBPG * CLSIZE)
+               alloc = addrmask[BUCKETINDX(NBPG * CLSIZE)];
+       else
+               alloc = addrmask[kup->ku_indx];
+       if (((u_long)addr & alloc) != 0)
+               panic("free: unaligned addr 0x%x, size %d, type %s, mask %d\n",
+                       addr, size, memname[type], alloc);
+#endif /* DIAGNOSTIC */

        IN;
        IN;

-       size = 1 << kup->ku_indx;

        if (size > MAXALLOCSAVE) {
        if (size > MAXALLOCSAVE) {

-               alloc = btokmemx(addr);
-               (void) memfree(&kmempt[alloc], (int)kup->ku_pagecnt, 1);
-               rmfree(kmemmap, (long)kup->ku_pagecnt, alloc + CLSIZE);
-               OUT;
-               if (wantkmemmap) {
-                       wakeup((caddr_t)&wantkmemmap);
-                       wantkmemmap = 0;
-               }
+               kmem_free(kmem_map, (vm_offset_t)addr, ctob(kup->ku_pagecnt));

 #ifdef KMEMSTATS
                size = kup->ku_pagecnt << PGSHIFT;
                ksp->ks_memuse -= size;
 #ifdef KMEMSTATS
                size = kup->ku_pagecnt << PGSHIFT;
                ksp->ks_memuse -= size;


@@ -199,6 +296,32 @@ free(addr, type)
                splx(s);
                return;
        }
                splx(s);
                return;
        }

+       freep = (struct freelist *)addr;
+#ifdef DIAGNOSTIC
+       /*
+        * Check for multiple frees. Use a quick check to see if
+        * it looks free before laboriously searching the freelist.
+        */
+       if (freep->spare0 == WEIRD_ADDR) {
+               for (cp = kbp->kb_next; cp; cp = *(caddr_t *)cp) {
+                       if (addr != cp)
+                               continue;
+                       printf("multiply freed item 0x%x\n", addr);
+                       panic("free: duplicated free");
+               }
+       }
+       /*
+        * Copy in known text to detect modification after freeing
+        * and to make it look free. Also, save the type being freed
+        * so we can list likely culprit if modification is detected
+        * when the object is reallocated.
+        */
+       copysize = size < MAX_COPY ? size : MAX_COPY;
+       end = (long *)&((caddr_t)addr)[copysize];
+       for (lp = (long *)addr; lp < end; lp++)
+               *lp = WEIRD_ADDR;
+       freep->type = type;
+#endif /* DIAGNOSTIC */

        if (size == 128) {
                long *lp = (long *)addr;
                lp[0] = lp[1] = lp[3] = lp[4] = -1;
        if (size == 128) {
                long *lp = (long *)addr;
                lp[0] = lp[1] = lp[3] = lp[4] = -1;


@@ -217,8 +340,12 @@ free(addr, type)
                wakeup((caddr_t)ksp);
        ksp->ks_inuse--;
 #endif
                wakeup((caddr_t)ksp);
        ksp->ks_inuse--;
 #endif

-       ((caddr_t *)addr)[2] = kbp->kb_next;
-       kbp->kb_next = addr;
+       if (kbp->kb_next == NULL)
+               kbp->kb_next = addr;
+       else
+               ((struct freelist *)kbp->kb_last)->next = addr;
+       freep->next = NULL;
+       kbp->kb_last = addr;

        OUT;
        splx(s);
 }
        OUT;
        splx(s);
 }


@@ -240,8 +367,11 @@ kmeminit()
 #if    (MAXALLOCSAVE < CLBYTES)
                ERROR!_kmeminit:_MAXALLOCSAVE_too_small
 #endif
 #if    (MAXALLOCSAVE < CLBYTES)
                ERROR!_kmeminit:_MAXALLOCSAVE_too_small
 #endif

-       npg = ekmempt - kmempt;
-       rminit(kmemmap, (long)npg, (long)CLSIZE, "malloc map", npg);
+       npg = VM_KMEM_SIZE/ NBPG;
+       kmemusage = (struct kmemusage *) kmem_alloc(kernel_map,
+               (vm_size_t)(npg * sizeof(struct kmemusage)));
+       kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase,
+               (vm_offset_t *)&kmemlimit, (vm_size_t)(npg * NBPG), FALSE);

 #ifdef KMEMSTATS
        for (indx = 0; indx < MINBUCKET + 16; indx++) {
                if (1 << indx >= CLBYTES)
 #ifdef KMEMSTATS
        for (indx = 0; indx < MINBUCKET + 16; indx++) {
                if (1 << indx >= CLBYTES)