High watermark memory usage feature

include/Makefile

@@ -13,4 +13,4 @@ install::
 	cpdir . $(INC)
 	@chown -R bin $(INC)
 	@rm -f $(INC)/Makefile
-	if [ -f $(MKHEADERS) ] ; then sh $(MKHEADERS) ; fi
+#	if [ -f $(MKHEADERS) ] ; then sh $(MKHEADERS) ; fi

include/minix/type.h

@@ -54,6 +54,12 @@ struct hole {
   phys_clicks h_len;            /* how big is the hole? */
 };
 
+/* Memory info from PM. */
+struct pm_mem_info {
+	struct hole pmi_holes[_NR_HOLES];/* memory (un)allocations */
+	u32_t pmi_hi_watermark;		 /* highest ever-used click + 1 */
+};
+
 #define phys_cp_req vir_cp_req 
 struct vir_cp_req {
   struct vir_addr src;

servers/is/dmp_pm.c

@@ -104,33 +104,36 @@ PUBLIC void sigaction_dmp()
  *===========================================================================*/
 PUBLIC void holes_dmp(void)
 {
-	static struct hole holes[_NR_HOLES];
+	static struct pm_mem_info pmi;
 	int h;
 	int largest_bytes = 0, total_bytes = 0;
 
-	if(getsysinfo(PM_PROC_NR, SI_MEM_ALLOC, holes) != OK) {
+	if(getsysinfo(PM_PROC_NR, SI_MEM_ALLOC, &pmi) != OK) {
 		printf("Obtaining memory hole list failed.\n");
 		return;
 	}
 	printf("Available memory stats\n");
 
 	for(h = 0; h < _NR_HOLES; h++) {
-		if(holes[h].h_base && holes[h].h_len) {
+		if(pmi.pmi_holes[h].h_base && pmi.pmi_holes[h].h_len) {
 			int bytes;
-			bytes = (holes[h].h_len << CLICK_SHIFT);
+			bytes = (pmi.pmi_holes[h].h_len << CLICK_SHIFT);
 			printf("%08lx: %6d kB\n",
-				holes[h].h_base << CLICK_SHIFT, bytes / 1024);
+				pmi.pmi_holes[h].h_base << CLICK_SHIFT, bytes / 1024);
 			if(bytes > largest_bytes) largest_bytes = bytes;
 			total_bytes += bytes;
 		}
 	}
-	printf("\nTotal memory free: %d kB\n"
+	printf("\n"
-		"Largest contiguous chunk: %d kB\n"
+		"Total memory free:     %7d kB\n"
-		"Uncontiguous rest: %d kB (%d%% of total free)\n",
+		"Largest chunk:         %7d kB\n"
+		"Uncontiguous rest:     %7d kB (%d%% of total free)\n"
+		"Memory high watermark: %7d kB\n",
 		total_bytes/1024,
 		largest_bytes/1024,
 		(total_bytes-largest_bytes)/1024,
-		100*(total_bytes/100-largest_bytes/100)/total_bytes);
+		100*(total_bytes/100-largest_bytes/100)/total_bytes,
+		(pmi.pmi_hi_watermark/1024 << CLICK_SHIFT));
 
 	return;
 }

servers/pm/alloc.c

@@ -32,6 +32,7 @@
 #define NIL_HOLE (struct hole *) 0
 
 PRIVATE struct hole hole[_NR_HOLES];
+PRIVATE u32_t high_watermark = 0;
 
 PRIVATE struct hole *hole_head;	/* pointer to first hole */
 PRIVATE struct hole *free_slots;/* ptr to list of unused table slots */
@@ -79,6 +80,10 @@ phys_clicks clicks;		/* amount of memory requested */
 			hp->h_base += clicks;	/* bite a piece off */
 			hp->h_len -= clicks;	/* ditto */
 
+			/* Remember new high watermark of used memory. */
+			if(hp->h_base > high_watermark)
+				high_watermark = hp->h_base;
+
 			/* Delete the hole if used up completely. */
 			if (hp->h_len == 0) del_slot(prev_ptr, hp);
 
@@ -253,11 +258,12 @@ phys_clicks *free;		/* memory size summaries */
 /*===========================================================================*
  *				mem_holes_copy				     *
  *===========================================================================*/
-PUBLIC int mem_holes_copy(struct hole *holecopies, size_t *bytes)
+PUBLIC int mem_holes_copy(struct hole *holecopies, size_t *bytes, u32_t *hi)
 {
 	if(*bytes < sizeof(hole)) return ENOSPC;
 	memcpy(holecopies, hole, sizeof(hole));
 	*bytes = sizeof(hole);
+	*hi = high_watermark;
 	return OK;
 }
 

servers/pm/misc.c

@@ -60,7 +60,7 @@ PUBLIC int do_getsysinfo()
   vir_bytes src_addr, dst_addr;
   struct kinfo kinfo;
   size_t len;
-  static struct hole holes[_NR_HOLES];
+  static struct pm_mem_info pmi;
   int s, r;
   size_t holesize;
 
@@ -80,10 +80,12 @@ PUBLIC int do_getsysinfo()
         len = sizeof(struct mproc) * NR_PROCS;
         break;
   case SI_MEM_ALLOC:
-  	holesize = sizeof(holes);
+  	holesize = sizeof(pmi.pmi_holes);
-	if((r=mem_holes_copy(holes, &holesize)) != OK) return r;
+	if((r=mem_holes_copy(pmi.pmi_holes, &holesize,
-	src_addr = (vir_bytes) holes;
+	   &pmi.pmi_hi_watermark)) != OK)
-	len = holesize;
+		return r;
+	src_addr = (vir_bytes) &pmi;
+	len = sizeof(pmi);
 	break;
   default:
   	return(EINVAL);

servers/pm/proto.h

@@ -20,7 +20,7 @@ _PROTOTYPE( void swap_inqueue, (struct mproc *rmp)			);
 #define swap_in()			((void)0)
 #define swap_inqueue(rmp)		((void)0)
 #endif /* !SWAP */
-_PROTOTYPE(int mem_holes_copy, (struct hole *, size_t *)		);
+_PROTOTYPE(int mem_holes_copy, (struct hole *, size_t *, u32_t *)	);
 
 /* break.c */
 _PROTOTYPE( int adjust, (struct mproc *rmp,