aboutsummaryrefslogtreecommitdiffstats
path: root/arch/sparc64/mm/tsb.c
diff options
context:
space:
mode:
authorSam Ravnborg <sam@ravnborg.org>2008-11-16 23:08:45 -0500
committerDavid S. Miller <davem@davemloft.net>2008-12-04 12:16:59 -0500
commit27137e5285a3388e8f86d7bc5fe0ed8b92bd4624 (patch)
tree70cd698fb5561743913b5f7615f61df6e8883537 /arch/sparc64/mm/tsb.c
parentc37ddd936d96b46cf2bb17e7b1a18b2bd24ec1fb (diff)
sparc,sparc64: unify mm/
- move all sparc64/mm/ files to arch/sparc/mm/ - commonly named files are named _64.c - add files to sparc/mm/Makefile preserving link order - delete now unused sparc64/mm/Makefile - sparc64 now finds mm/ in sparc Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/sparc64/mm/tsb.c')
-rw-r--r--arch/sparc64/mm/tsb.c496
1 files changed, 0 insertions, 496 deletions
diff --git a/arch/sparc64/mm/tsb.c b/arch/sparc64/mm/tsb.c
deleted file mode 100644
index f0282fad632a..000000000000
--- a/arch/sparc64/mm/tsb.c
+++ /dev/null
@@ -1,496 +0,0 @@
1/* arch/sparc64/mm/tsb.c
2 *
3 * Copyright (C) 2006, 2008 David S. Miller <davem@davemloft.net>
4 */
5
6#include <linux/kernel.h>
7#include <linux/preempt.h>
8#include <asm/system.h>
9#include <asm/page.h>
10#include <asm/tlbflush.h>
11#include <asm/tlb.h>
12#include <asm/mmu_context.h>
13#include <asm/pgtable.h>
14#include <asm/tsb.h>
15#include <asm/oplib.h>
16
17extern struct tsb swapper_tsb[KERNEL_TSB_NENTRIES];
18
19static inline unsigned long tsb_hash(unsigned long vaddr, unsigned long hash_shift, unsigned long nentries)
20{
21 vaddr >>= hash_shift;
22 return vaddr & (nentries - 1);
23}
24
25static inline int tag_compare(unsigned long tag, unsigned long vaddr)
26{
27 return (tag == (vaddr >> 22));
28}
29
30/* TSB flushes need only occur on the processor initiating the address
31 * space modification, not on each cpu the address space has run on.
32 * Only the TLB flush needs that treatment.
33 */
34
35void flush_tsb_kernel_range(unsigned long start, unsigned long end)
36{
37 unsigned long v;
38
39 for (v = start; v < end; v += PAGE_SIZE) {
40 unsigned long hash = tsb_hash(v, PAGE_SHIFT,
41 KERNEL_TSB_NENTRIES);
42 struct tsb *ent = &swapper_tsb[hash];
43
44 if (tag_compare(ent->tag, v))
45 ent->tag = (1UL << TSB_TAG_INVALID_BIT);
46 }
47}
48
49static void __flush_tsb_one(struct mmu_gather *mp, unsigned long hash_shift, unsigned long tsb, unsigned long nentries)
50{
51 unsigned long i;
52
53 for (i = 0; i < mp->tlb_nr; i++) {
54 unsigned long v = mp->vaddrs[i];
55 unsigned long tag, ent, hash;
56
57 v &= ~0x1UL;
58
59 hash = tsb_hash(v, hash_shift, nentries);
60 ent = tsb + (hash * sizeof(struct tsb));
61 tag = (v >> 22UL);
62
63 tsb_flush(ent, tag);
64 }
65}
66
67void flush_tsb_user(struct mmu_gather *mp)
68{
69 struct mm_struct *mm = mp->mm;
70 unsigned long nentries, base, flags;
71
72 spin_lock_irqsave(&mm->context.lock, flags);
73
74 base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb;
75 nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries;
76 if (tlb_type == cheetah_plus || tlb_type == hypervisor)
77 base = __pa(base);
78 __flush_tsb_one(mp, PAGE_SHIFT, base, nentries);
79
80#ifdef CONFIG_HUGETLB_PAGE
81 if (mm->context.tsb_block[MM_TSB_HUGE].tsb) {
82 base = (unsigned long) mm->context.tsb_block[MM_TSB_HUGE].tsb;
83 nentries = mm->context.tsb_block[MM_TSB_HUGE].tsb_nentries;
84 if (tlb_type == cheetah_plus || tlb_type == hypervisor)
85 base = __pa(base);
86 __flush_tsb_one(mp, HPAGE_SHIFT, base, nentries);
87 }
88#endif
89 spin_unlock_irqrestore(&mm->context.lock, flags);
90}
91
92#if defined(CONFIG_SPARC64_PAGE_SIZE_8KB)
93#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_8K
94#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_8K
95#elif defined(CONFIG_SPARC64_PAGE_SIZE_64KB)
96#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_64K
97#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_64K
98#else
99#error Broken base page size setting...
100#endif
101
102#ifdef CONFIG_HUGETLB_PAGE
103#if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
104#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_64K
105#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_64K
106#elif defined(CONFIG_HUGETLB_PAGE_SIZE_512K)
107#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_512K
108#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_512K
109#elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB)
110#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_4MB
111#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_4MB
112#else
113#error Broken huge page size setting...
114#endif
115#endif
116
117static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_idx, unsigned long tsb_bytes)
118{
119 unsigned long tsb_reg, base, tsb_paddr;
120 unsigned long page_sz, tte;
121
122 mm->context.tsb_block[tsb_idx].tsb_nentries =
123 tsb_bytes / sizeof(struct tsb);
124
125 base = TSBMAP_BASE;
126 tte = pgprot_val(PAGE_KERNEL_LOCKED);
127 tsb_paddr = __pa(mm->context.tsb_block[tsb_idx].tsb);
128 BUG_ON(tsb_paddr & (tsb_bytes - 1UL));
129
130 /* Use the smallest page size that can map the whole TSB
131 * in one TLB entry.
132 */
133 switch (tsb_bytes) {
134 case 8192 << 0:
135 tsb_reg = 0x0UL;
136#ifdef DCACHE_ALIASING_POSSIBLE
137 base += (tsb_paddr & 8192);
138#endif
139 page_sz = 8192;
140 break;
141
142 case 8192 << 1:
143 tsb_reg = 0x1UL;
144 page_sz = 64 * 1024;
145 break;
146
147 case 8192 << 2:
148 tsb_reg = 0x2UL;
149 page_sz = 64 * 1024;
150 break;
151
152 case 8192 << 3:
153 tsb_reg = 0x3UL;
154 page_sz = 64 * 1024;
155 break;
156
157 case 8192 << 4:
158 tsb_reg = 0x4UL;
159 page_sz = 512 * 1024;
160 break;
161
162 case 8192 << 5:
163 tsb_reg = 0x5UL;
164 page_sz = 512 * 1024;
165 break;
166
167 case 8192 << 6:
168 tsb_reg = 0x6UL;
169 page_sz = 512 * 1024;
170 break;
171
172 case 8192 << 7:
173 tsb_reg = 0x7UL;
174 page_sz = 4 * 1024 * 1024;
175 break;
176
177 default:
178 printk(KERN_ERR "TSB[%s:%d]: Impossible TSB size %lu, killing process.\n",
179 current->comm, current->pid, tsb_bytes);
180 do_exit(SIGSEGV);
181 };
182 tte |= pte_sz_bits(page_sz);
183
184 if (tlb_type == cheetah_plus || tlb_type == hypervisor) {
185 /* Physical mapping, no locked TLB entry for TSB. */
186 tsb_reg |= tsb_paddr;
187
188 mm->context.tsb_block[tsb_idx].tsb_reg_val = tsb_reg;
189 mm->context.tsb_block[tsb_idx].tsb_map_vaddr = 0;
190 mm->context.tsb_block[tsb_idx].tsb_map_pte = 0;
191 } else {
192 tsb_reg |= base;
193 tsb_reg |= (tsb_paddr & (page_sz - 1UL));
194 tte |= (tsb_paddr & ~(page_sz - 1UL));
195
196 mm->context.tsb_block[tsb_idx].tsb_reg_val = tsb_reg;
197 mm->context.tsb_block[tsb_idx].tsb_map_vaddr = base;
198 mm->context.tsb_block[tsb_idx].tsb_map_pte = tte;
199 }
200
201 /* Setup the Hypervisor TSB descriptor. */
202 if (tlb_type == hypervisor) {
203 struct hv_tsb_descr *hp = &mm->context.tsb_descr[tsb_idx];
204
205 switch (tsb_idx) {
206 case MM_TSB_BASE:
207 hp->pgsz_idx = HV_PGSZ_IDX_BASE;
208 break;
209#ifdef CONFIG_HUGETLB_PAGE
210 case MM_TSB_HUGE:
211 hp->pgsz_idx = HV_PGSZ_IDX_HUGE;
212 break;
213#endif
214 default:
215 BUG();
216 };
217 hp->assoc = 1;
218 hp->num_ttes = tsb_bytes / 16;
219 hp->ctx_idx = 0;
220 switch (tsb_idx) {
221 case MM_TSB_BASE:
222 hp->pgsz_mask = HV_PGSZ_MASK_BASE;
223 break;
224#ifdef CONFIG_HUGETLB_PAGE
225 case MM_TSB_HUGE:
226 hp->pgsz_mask = HV_PGSZ_MASK_HUGE;
227 break;
228#endif
229 default:
230 BUG();
231 };
232 hp->tsb_base = tsb_paddr;
233 hp->resv = 0;
234 }
235}
236
237static struct kmem_cache *tsb_caches[8] __read_mostly;
238
239static const char *tsb_cache_names[8] = {
240 "tsb_8KB",
241 "tsb_16KB",
242 "tsb_32KB",
243 "tsb_64KB",
244 "tsb_128KB",
245 "tsb_256KB",
246 "tsb_512KB",
247 "tsb_1MB",
248};
249
250void __init pgtable_cache_init(void)
251{
252 unsigned long i;
253
254 for (i = 0; i < 8; i++) {
255 unsigned long size = 8192 << i;
256 const char *name = tsb_cache_names[i];
257
258 tsb_caches[i] = kmem_cache_create(name,
259 size, size,
260 0, NULL);
261 if (!tsb_caches[i]) {
262 prom_printf("Could not create %s cache\n", name);
263 prom_halt();
264 }
265 }
266}
267
268/* When the RSS of an address space exceeds tsb_rss_limit for a TSB,
269 * do_sparc64_fault() invokes this routine to try and grow it.
270 *
271 * When we reach the maximum TSB size supported, we stick ~0UL into
272 * tsb_rss_limit for that TSB so the grow checks in do_sparc64_fault()
273 * will not trigger any longer.
274 *
275 * The TSB can be anywhere from 8K to 1MB in size, in increasing powers
276 * of two. The TSB must be aligned to it's size, so f.e. a 512K TSB
277 * must be 512K aligned. It also must be physically contiguous, so we
278 * cannot use vmalloc().
279 *
280 * The idea here is to grow the TSB when the RSS of the process approaches
281 * the number of entries that the current TSB can hold at once. Currently,
282 * we trigger when the RSS hits 3/4 of the TSB capacity.
283 */
284void tsb_grow(struct mm_struct *mm, unsigned long tsb_index, unsigned long rss)
285{
286 unsigned long max_tsb_size = 1 * 1024 * 1024;
287 unsigned long new_size, old_size, flags;
288 struct tsb *old_tsb, *new_tsb;
289 unsigned long new_cache_index, old_cache_index;
290 unsigned long new_rss_limit;
291 gfp_t gfp_flags;
292
293 if (max_tsb_size > (PAGE_SIZE << MAX_ORDER))
294 max_tsb_size = (PAGE_SIZE << MAX_ORDER);
295
296 new_cache_index = 0;
297 for (new_size = 8192; new_size < max_tsb_size; new_size <<= 1UL) {
298 unsigned long n_entries = new_size / sizeof(struct tsb);
299
300 n_entries = (n_entries * 3) / 4;
301 if (n_entries > rss)
302 break;
303
304 new_cache_index++;
305 }
306
307 if (new_size == max_tsb_size)
308 new_rss_limit = ~0UL;
309 else
310 new_rss_limit = ((new_size / sizeof(struct tsb)) * 3) / 4;
311
312retry_tsb_alloc:
313 gfp_flags = GFP_KERNEL;
314 if (new_size > (PAGE_SIZE * 2))
315 gfp_flags = __GFP_NOWARN | __GFP_NORETRY;
316
317 new_tsb = kmem_cache_alloc_node(tsb_caches[new_cache_index],
318 gfp_flags, numa_node_id());
319 if (unlikely(!new_tsb)) {
320 /* Not being able to fork due to a high-order TSB
321 * allocation failure is very bad behavior. Just back
322 * down to a 0-order allocation and force no TSB
323 * growing for this address space.
324 */
325 if (mm->context.tsb_block[tsb_index].tsb == NULL &&
326 new_cache_index > 0) {
327 new_cache_index = 0;
328 new_size = 8192;
329 new_rss_limit = ~0UL;
330 goto retry_tsb_alloc;
331 }
332
333 /* If we failed on a TSB grow, we are under serious
334 * memory pressure so don't try to grow any more.
335 */
336 if (mm->context.tsb_block[tsb_index].tsb != NULL)
337 mm->context.tsb_block[tsb_index].tsb_rss_limit = ~0UL;
338 return;
339 }
340
341 /* Mark all tags as invalid. */
342 tsb_init(new_tsb, new_size);
343
344 /* Ok, we are about to commit the changes. If we are
345 * growing an existing TSB the locking is very tricky,
346 * so WATCH OUT!
347 *
348 * We have to hold mm->context.lock while committing to the
349 * new TSB, this synchronizes us with processors in
350 * flush_tsb_user() and switch_mm() for this address space.
351 *
352 * But even with that lock held, processors run asynchronously
353 * accessing the old TSB via TLB miss handling. This is OK
354 * because those actions are just propagating state from the
355 * Linux page tables into the TSB, page table mappings are not
356 * being changed. If a real fault occurs, the processor will
357 * synchronize with us when it hits flush_tsb_user(), this is
358 * also true for the case where vmscan is modifying the page
359 * tables. The only thing we need to be careful with is to
360 * skip any locked TSB entries during copy_tsb().
361 *
362 * When we finish committing to the new TSB, we have to drop
363 * the lock and ask all other cpus running this address space
364 * to run tsb_context_switch() to see the new TSB table.
365 */
366 spin_lock_irqsave(&mm->context.lock, flags);
367
368 old_tsb = mm->context.tsb_block[tsb_index].tsb;
369 old_cache_index =
370 (mm->context.tsb_block[tsb_index].tsb_reg_val & 0x7UL);
371 old_size = (mm->context.tsb_block[tsb_index].tsb_nentries *
372 sizeof(struct tsb));
373
374
375 /* Handle multiple threads trying to grow the TSB at the same time.
376 * One will get in here first, and bump the size and the RSS limit.
377 * The others will get in here next and hit this check.
378 */
379 if (unlikely(old_tsb &&
380 (rss < mm->context.tsb_block[tsb_index].tsb_rss_limit))) {
381 spin_unlock_irqrestore(&mm->context.lock, flags);
382
383 kmem_cache_free(tsb_caches[new_cache_index], new_tsb);
384 return;
385 }
386
387 mm->context.tsb_block[tsb_index].tsb_rss_limit = new_rss_limit;
388
389 if (old_tsb) {
390 extern void copy_tsb(unsigned long old_tsb_base,
391 unsigned long old_tsb_size,
392 unsigned long new_tsb_base,
393 unsigned long new_tsb_size);
394 unsigned long old_tsb_base = (unsigned long) old_tsb;
395 unsigned long new_tsb_base = (unsigned long) new_tsb;
396
397 if (tlb_type == cheetah_plus || tlb_type == hypervisor) {
398 old_tsb_base = __pa(old_tsb_base);
399 new_tsb_base = __pa(new_tsb_base);
400 }
401 copy_tsb(old_tsb_base, old_size, new_tsb_base, new_size);
402 }
403
404 mm->context.tsb_block[tsb_index].tsb = new_tsb;
405 setup_tsb_params(mm, tsb_index, new_size);
406
407 spin_unlock_irqrestore(&mm->context.lock, flags);
408
409 /* If old_tsb is NULL, we're being invoked for the first time
410 * from init_new_context().
411 */
412 if (old_tsb) {
413 /* Reload it on the local cpu. */
414 tsb_context_switch(mm);
415
416 /* Now force other processors to do the same. */
417 preempt_disable();
418 smp_tsb_sync(mm);
419 preempt_enable();
420
421 /* Now it is safe to free the old tsb. */
422 kmem_cache_free(tsb_caches[old_cache_index], old_tsb);
423 }
424}
425
426int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
427{
428#ifdef CONFIG_HUGETLB_PAGE
429 unsigned long huge_pte_count;
430#endif
431 unsigned int i;
432
433 spin_lock_init(&mm->context.lock);
434
435 mm->context.sparc64_ctx_val = 0UL;
436
437#ifdef CONFIG_HUGETLB_PAGE
438 /* We reset it to zero because the fork() page copying
439 * will re-increment the counters as the parent PTEs are
440 * copied into the child address space.
441 */
442 huge_pte_count = mm->context.huge_pte_count;
443 mm->context.huge_pte_count = 0;
444#endif
445
446 /* copy_mm() copies over the parent's mm_struct before calling
447 * us, so we need to zero out the TSB pointer or else tsb_grow()
448 * will be confused and think there is an older TSB to free up.
449 */
450 for (i = 0; i < MM_NUM_TSBS; i++)
451 mm->context.tsb_block[i].tsb = NULL;
452
453 /* If this is fork, inherit the parent's TSB size. We would
454 * grow it to that size on the first page fault anyways.
455 */
456 tsb_grow(mm, MM_TSB_BASE, get_mm_rss(mm));
457
458#ifdef CONFIG_HUGETLB_PAGE
459 if (unlikely(huge_pte_count))
460 tsb_grow(mm, MM_TSB_HUGE, huge_pte_count);
461#endif
462
463 if (unlikely(!mm->context.tsb_block[MM_TSB_BASE].tsb))
464 return -ENOMEM;
465
466 return 0;
467}
468
469static void tsb_destroy_one(struct tsb_config *tp)
470{
471 unsigned long cache_index;
472
473 if (!tp->tsb)
474 return;
475 cache_index = tp->tsb_reg_val & 0x7UL;
476 kmem_cache_free(tsb_caches[cache_index], tp->tsb);
477 tp->tsb = NULL;
478 tp->tsb_reg_val = 0UL;
479}
480
481void destroy_context(struct mm_struct *mm)
482{
483 unsigned long flags, i;
484
485 for (i = 0; i < MM_NUM_TSBS; i++)
486 tsb_destroy_one(&mm->context.tsb_block[i]);
487
488 spin_lock_irqsave(&ctx_alloc_lock, flags);
489
490 if (CTX_VALID(mm->context)) {
491 unsigned long nr = CTX_NRBITS(mm->context);
492 mmu_context_bmap[nr>>6] &= ~(1UL << (nr & 63));
493 }
494
495 spin_unlock_irqrestore(&ctx_alloc_lock, flags);
496}
generated by cgit v1.2.2 (git 2.25.0) at 2025-03-05 09:35:43 -0500