xref: /titanic_41/usr/src/uts/sun4/os/memnode.c (revision b823d4c7196446cdc012453fe0775037298d56cb)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/systm.h>
30 #include <sys/platform_module.h>
31 #include <sys/sysmacros.h>
32 #include <sys/atomic.h>
33 #include <sys/memlist.h>
34 #include <sys/memnode.h>
35 #include <vm/vm_dep.h>
36 
37 int max_mem_nodes = 1;		/* max memory nodes on this system */
38 
39 struct mem_node_conf mem_node_config[MAX_MEM_NODES];
40 int mem_node_pfn_shift;
41 /*
42  * num_memnodes should be updated atomically and always >=
43  * the number of bits in memnodes_mask or the algorithm may fail.
44  */
45 uint16_t num_memnodes;
46 mnodeset_t memnodes_mask; /* assumes 8*(sizeof(mnodeset_t)) >= MAX_MEM_NODES */
47 
48 /*
49  * If set, mem_node_physalign should be a power of two, and
50  * should reflect the minimum address alignment of each node.
51  */
52 uint64_t mem_node_physalign;
53 
54 /*
55  * Platform hooks we will need.
56  */
57 
58 #pragma weak plat_build_mem_nodes
59 #pragma weak plat_slice_add
60 #pragma weak plat_slice_del
61 
62 /*
63  * Adjust the memnode config after a DR operation.
64  *
65  * It is rather tricky to do these updates since we can't
66  * protect the memnode structures with locks, so we must
67  * be mindful of the order in which updates and reads to
68  * these values can occur.
69  */
70 void
71 mem_node_add_slice(pfn_t start, pfn_t end)
72 {
73 	int mnode;
74 	mnodeset_t newmask, oldmask;
75 
76 	/*
77 	 * DR will pass us the first pfn that is allocatable.
78 	 * We need to round down to get the real start of
79 	 * the slice.
80 	 */
81 	if (mem_node_physalign) {
82 		start &= ~(btop(mem_node_physalign) - 1);
83 		end = roundup(end, btop(mem_node_physalign)) - 1;
84 	}
85 
86 	if (&plat_slice_add)
87 		plat_slice_add(start, end);
88 
89 	mnode = PFN_2_MEM_NODE(start);
90 	ASSERT(mnode < max_mem_nodes);
91 
92 	if (cas32((uint32_t *)&mem_node_config[mnode].exists, 0, 1)) {
93 		/*
94 		 * Add slice to existing node.
95 		 */
96 		if (start < mem_node_config[mnode].physbase)
97 			mem_node_config[mnode].physbase = start;
98 		if (end > mem_node_config[mnode].physmax)
99 			mem_node_config[mnode].physmax = end;
100 	} else {
101 		mem_node_config[mnode].physbase = start;
102 		mem_node_config[mnode].physmax = end;
103 		atomic_add_16(&num_memnodes, 1);
104 		do {
105 			oldmask = memnodes_mask;
106 			newmask = memnodes_mask | (1ull << mnode);
107 		} while (cas64(&memnodes_mask, oldmask, newmask) != oldmask);
108 	}
109 	/*
110 	 * Let the common lgrp framework know about the new memory
111 	 */
112 	lgrp_config(LGRP_CONFIG_MEM_ADD, mnode, MEM_NODE_2_LGRPHAND(mnode));
113 }
114 
115 /* ARGSUSED */
116 void
117 mem_node_pre_del_slice(pfn_t start, pfn_t end)
118 {
119 	int mnode = PFN_2_MEM_NODE(start);
120 
121 	ASSERT(mnode < max_mem_nodes);
122 	ASSERT(mem_node_config[mnode].exists == 1);
123 }
124 
125 /*
126  * Remove a PFN range from a memnode.  On some platforms,
127  * the memnode will be created with physbase at the first
128  * allocatable PFN, but later deleted with the MC slice
129  * base address converted to a PFN, in which case we need
130  * to assume physbase and up.
131  */
132 void
133 mem_node_post_del_slice(pfn_t start, pfn_t end, int cancelled)
134 {
135 	int mnode;
136 	pgcnt_t delta_pgcnt, node_size;
137 	mnodeset_t omask, nmask;
138 
139 	if (mem_node_physalign) {
140 		start &= ~(btop(mem_node_physalign) - 1);
141 		end = roundup(end, btop(mem_node_physalign)) - 1;
142 	}
143 	mnode = PFN_2_MEM_NODE(start);
144 
145 	ASSERT(mnode < max_mem_nodes);
146 	ASSERT(mem_node_config[mnode].exists == 1);
147 
148 	if (!cancelled) {
149 		delta_pgcnt = end - start;
150 		node_size = mem_node_config[mnode].physmax -
151 				mem_node_config[mnode].physbase;
152 
153 		if (node_size > delta_pgcnt) {
154 			/*
155 			 * Subtract the slice from the memnode.
156 			 */
157 			if (start <= mem_node_config[mnode].physbase)
158 				mem_node_config[mnode].physbase = end + 1;
159 			ASSERT(end <= mem_node_config[mnode].physmax);
160 			if (end == mem_node_config[mnode].physmax)
161 				mem_node_config[mnode].physmax = start - 1;
162 		} else {
163 
164 			/*
165 			 * Let the common lgrp framework know the mnode is
166 			 * leaving
167 			 */
168 			lgrp_config(LGRP_CONFIG_MEM_DEL, mnode,
169 			    MEM_NODE_2_LGRPHAND(mnode));
170 
171 			/*
172 			 * Delete the whole node.
173 			 */
174 			ASSERT(MNODE_PGCNT(mnode) == 0);
175 			do {
176 				omask = memnodes_mask;
177 				nmask = omask & ~(1ull << mnode);
178 			} while (cas64(&memnodes_mask, omask, nmask) != omask);
179 			atomic_add_16(&num_memnodes, -1);
180 			mem_node_config[mnode].exists = 0;
181 		}
182 
183 		if (&plat_slice_del)
184 			plat_slice_del(start, end);
185 	}
186 }
187 
188 void
189 startup_build_mem_nodes(u_longlong_t *list, size_t nelems)
190 {
191 	size_t	elem;
192 	pfn_t	basepfn;
193 	pgcnt_t	npgs;
194 
195 	/* LINTED: ASSERT will always true or false */
196 	ASSERT(NBBY * sizeof (mnodeset_t) >= max_mem_nodes);
197 
198 	if (&plat_build_mem_nodes) {
199 		plat_build_mem_nodes(list, nelems);
200 	} else {
201 		/*
202 		 * Boot install lists are arranged <addr, len>, ...
203 		 */
204 		for (elem = 0; elem < nelems; elem += 2) {
205 			basepfn = btop(list[elem]);
206 			npgs = btop(list[elem+1]);
207 			mem_node_add_slice(basepfn, basepfn + npgs - 1);
208 		}
209 		mem_node_physalign = 0;
210 		mem_node_pfn_shift = 0;
211 	}
212 }
213 
214 /*
215  * Allocate an unassigned memnode.
216  */
217 int
218 mem_node_alloc()
219 {
220 	int mnode;
221 	mnodeset_t newmask, oldmask;
222 
223 	/*
224 	 * Find an unused memnode.  Update it atomically to prevent
225 	 * a first time memnode creation race.
226 	 */
227 	for (mnode = 0; mnode < max_mem_nodes; mnode++)
228 		if (cas32((uint32_t *)&mem_node_config[mnode].exists,
229 			0, 1) == 0)
230 			break;
231 
232 	if (mnode >= max_mem_nodes)
233 			panic("Out of free memnodes\n");
234 
235 	mem_node_config[mnode].physbase = (uint64_t)-1;
236 	mem_node_config[mnode].physmax = 0;
237 	atomic_add_16(&num_memnodes, 1);
238 	do {
239 		oldmask = memnodes_mask;
240 		newmask = memnodes_mask | (1ull << mnode);
241 	} while (cas64(&memnodes_mask, oldmask, newmask) != oldmask);
242 
243 	return (mnode);
244 }
245 
246 /*
247  * Find the intersection between a memnode and a memlist
248  * and returns the number of pages that overlap.
249  *
250  * Assumes the list is protected from DR operations by
251  * the memlist lock.
252  */
253 pgcnt_t
254 mem_node_memlist_pages(int mnode, struct memlist *mlist)
255 {
256 	pfn_t		base, end;
257 	pfn_t		cur_base, cur_end;
258 	pgcnt_t		npgs;
259 	struct memlist	*pmem;
260 
261 	base = mem_node_config[mnode].physbase;
262 	end = mem_node_config[mnode].physmax;
263 	npgs = 0;
264 
265 	memlist_read_lock();
266 
267 	for (pmem = mlist; pmem; pmem = pmem->next) {
268 		cur_base = btop(pmem->address);
269 		cur_end = cur_base + btop(pmem->size) - 1;
270 		if (end <= cur_base || base >= cur_end)
271 			continue;
272 		npgs = npgs + (MIN(cur_end, end) -
273 		    MAX(cur_base, base)) + 1;
274 	}
275 
276 	memlist_read_unlock();
277 
278 	return (npgs);
279 }
280