xref: /freebsd/sys/dev/hwpmc/hwpmc_soft.c (revision d9a42747950146bf03cda7f6e25d219253f8a57a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2012 Fabien Thomas
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/pmc.h>
34 #include <sys/pmckern.h>
35 #include <sys/systm.h>
36 #include <sys/mutex.h>
37 
38 #include <machine/cpu.h>
39 #include <machine/cpufunc.h>
40 
41 #include "hwpmc_soft.h"
42 
43 /*
44  * Software PMC support.
45  */
46 
47 #define	SOFT_CAPS (PMC_CAP_READ | PMC_CAP_WRITE | PMC_CAP_INTERRUPT | \
48     PMC_CAP_USER | PMC_CAP_SYSTEM)
49 
50 struct soft_descr {
51 	struct pmc_descr pm_descr;  /* "base class" */
52 };
53 
54 static struct soft_descr soft_pmcdesc[SOFT_NPMCS] =
55 {
56 #define	SOFT_PMCDESCR(N)				\
57 	{						\
58 		.pm_descr =				\
59 		{					\
60 			.pd_name = #N,			\
61 			.pd_class = PMC_CLASS_SOFT,	\
62 			.pd_caps = SOFT_CAPS,		\
63 			.pd_width = 64			\
64 		},					\
65 	}
66 
67 	SOFT_PMCDESCR(SOFT0),
68 	SOFT_PMCDESCR(SOFT1),
69 	SOFT_PMCDESCR(SOFT2),
70 	SOFT_PMCDESCR(SOFT3),
71 	SOFT_PMCDESCR(SOFT4),
72 	SOFT_PMCDESCR(SOFT5),
73 	SOFT_PMCDESCR(SOFT6),
74 	SOFT_PMCDESCR(SOFT7),
75 	SOFT_PMCDESCR(SOFT8),
76 	SOFT_PMCDESCR(SOFT9),
77 	SOFT_PMCDESCR(SOFT10),
78 	SOFT_PMCDESCR(SOFT11),
79 	SOFT_PMCDESCR(SOFT12),
80 	SOFT_PMCDESCR(SOFT13),
81 	SOFT_PMCDESCR(SOFT14),
82 	SOFT_PMCDESCR(SOFT15)
83 };
84 
85 /*
86  * Per-CPU data structure.
87  */
88 
89 struct soft_cpu {
90 	struct pmc_hw	soft_hw[SOFT_NPMCS];
91 	pmc_value_t	soft_values[SOFT_NPMCS];
92 };
93 
94 
95 static struct soft_cpu **soft_pcpu;
96 
97 static int
98 soft_allocate_pmc(int cpu, int ri, struct pmc *pm,
99     const struct pmc_op_pmcallocate *a)
100 {
101 	enum pmc_event ev;
102 	struct pmc_soft *ps;
103 
104 	(void) cpu;
105 
106 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
107 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
108 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
109 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
110 
111 	if (a->pm_class != PMC_CLASS_SOFT)
112 		return (EINVAL);
113 
114 	if ((pm->pm_caps & SOFT_CAPS) == 0)
115 		return (EINVAL);
116 
117 	if ((pm->pm_caps & ~SOFT_CAPS) != 0)
118 		return (EPERM);
119 
120 	ev = pm->pm_event;
121 	if ((int)ev < PMC_EV_SOFT_FIRST || (int)ev > PMC_EV_SOFT_LAST)
122 		return (EINVAL);
123 
124 	/* Check if event is registered. */
125 	ps = pmc_soft_ev_acquire(ev);
126 	if (ps == NULL)
127 		return (EINVAL);
128 	pmc_soft_ev_release(ps);
129 	/* Module unload is protected by pmc SX lock. */
130 	if (ps->ps_alloc != NULL)
131 		ps->ps_alloc();
132 
133 	return (0);
134 }
135 
136 static int
137 soft_config_pmc(int cpu, int ri, struct pmc *pm)
138 {
139 	struct pmc_hw *phw;
140 
141 	PMCDBG3(MDP,CFG,1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
142 
143 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
144 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
145 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
146 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
147 
148 	phw = &soft_pcpu[cpu]->soft_hw[ri];
149 
150 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
151 	    ("[soft,%d] pm=%p phw->pm=%p hwpmc not unconfigured", __LINE__,
152 	    pm, phw->phw_pmc));
153 
154 	phw->phw_pmc = pm;
155 
156 	return (0);
157 }
158 
159 static int
160 soft_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
161 {
162 	int error;
163 	size_t copied;
164 	const struct soft_descr *pd;
165 	struct pmc_hw *phw;
166 
167 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
168 	    ("[soft,%d] illegal CPU %d", __LINE__, cpu));
169 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
170 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
171 
172 	phw = &soft_pcpu[cpu]->soft_hw[ri];
173 	pd  = &soft_pmcdesc[ri];
174 
175 	if ((error = copystr(pd->pm_descr.pd_name, pi->pm_name,
176 	    PMC_NAME_MAX, &copied)) != 0)
177 		return (error);
178 
179 	pi->pm_class = pd->pm_descr.pd_class;
180 
181 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
182 		pi->pm_enabled = TRUE;
183 		*ppmc          = phw->phw_pmc;
184 	} else {
185 		pi->pm_enabled = FALSE;
186 		*ppmc          = NULL;
187 	}
188 
189 	return (0);
190 }
191 
192 static int
193 soft_get_config(int cpu, int ri, struct pmc **ppm)
194 {
195 	(void) ri;
196 
197 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
198 	    ("[soft,%d] illegal CPU %d", __LINE__, cpu));
199 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
200 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
201 
202 	*ppm = soft_pcpu[cpu]->soft_hw[ri].phw_pmc;
203 	return (0);
204 }
205 
206 static int
207 soft_pcpu_fini(struct pmc_mdep *md, int cpu)
208 {
209 	int ri;
210 	struct pmc_cpu *pc;
211 
212 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
213 	    ("[soft,%d] illegal cpu %d", __LINE__, cpu));
214 	KASSERT(soft_pcpu[cpu] != NULL, ("[soft,%d] null pcpu", __LINE__));
215 
216 	free(soft_pcpu[cpu], M_PMC);
217 	soft_pcpu[cpu] = NULL;
218 
219 	ri = md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_ri;
220 
221 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
222 	    ("[soft,%d] ri=%d", __LINE__, ri));
223 
224 	pc = pmc_pcpu[cpu];
225 	pc->pc_hwpmcs[ri] = NULL;
226 
227 	return (0);
228 }
229 
230 static int
231 soft_pcpu_init(struct pmc_mdep *md, int cpu)
232 {
233 	int first_ri, n;
234 	struct pmc_cpu *pc;
235 	struct soft_cpu *soft_pc;
236 	struct pmc_hw *phw;
237 
238 
239 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
240 	    ("[soft,%d] illegal cpu %d", __LINE__, cpu));
241 	KASSERT(soft_pcpu, ("[soft,%d] null pcpu", __LINE__));
242 	KASSERT(soft_pcpu[cpu] == NULL, ("[soft,%d] non-null per-cpu",
243 	    __LINE__));
244 
245 	soft_pc = malloc(sizeof(struct soft_cpu), M_PMC, M_WAITOK|M_ZERO);
246 	pc = pmc_pcpu[cpu];
247 
248 	KASSERT(pc != NULL, ("[soft,%d] cpu %d null per-cpu", __LINE__, cpu));
249 
250 	soft_pcpu[cpu] = soft_pc;
251 	phw = soft_pc->soft_hw;
252 	first_ri = md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_ri;
253 
254 	for (n = 0; n < SOFT_NPMCS; n++, phw++) {
255 		phw->phw_state = PMC_PHW_FLAG_IS_ENABLED |
256 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(n);
257 		phw->phw_pmc = NULL;
258 		pc->pc_hwpmcs[n + first_ri] = phw;
259 	}
260 
261 	return (0);
262 }
263 
264 static int
265 soft_read_pmc(int cpu, int ri, pmc_value_t *v)
266 {
267 	struct pmc *pm __diagused;
268 	const struct pmc_hw *phw;
269 
270 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
271 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
272 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
273 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
274 
275 	phw = &soft_pcpu[cpu]->soft_hw[ri];
276 	pm  = phw->phw_pmc;
277 
278 	KASSERT(pm != NULL,
279 	    ("[soft,%d] no owner for PHW [cpu%d,pmc%d]", __LINE__, cpu, ri));
280 
281 	PMCDBG1(MDP,REA,1,"soft-read id=%d", ri);
282 
283 	*v = soft_pcpu[cpu]->soft_values[ri];
284 
285 	return (0);
286 }
287 
288 static int
289 soft_write_pmc(int cpu, int ri, pmc_value_t v)
290 {
291 	struct pmc *pm __diagused;
292 
293 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
294 	    ("[soft,%d] illegal cpu value %d", __LINE__, cpu));
295 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
296 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
297 
298 	pm = soft_pcpu[cpu]->soft_hw[ri].phw_pmc;
299 
300 	KASSERT(pm,
301 	    ("[soft,%d] cpu %d ri %d pmc not configured", __LINE__, cpu, ri));
302 
303 	PMCDBG3(MDP,WRI,1, "soft-write cpu=%d ri=%d v=%jx", cpu, ri, v);
304 
305 	soft_pcpu[cpu]->soft_values[ri] = v;
306 
307 	return (0);
308 }
309 
310 static int
311 soft_release_pmc(int cpu, int ri, struct pmc *pmc)
312 {
313 	struct pmc_hw *phw __diagused;
314 	enum pmc_event ev;
315 	struct pmc_soft *ps;
316 
317 	(void) pmc;
318 
319 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
320 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
321 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
322 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
323 
324 	phw = &soft_pcpu[cpu]->soft_hw[ri];
325 
326 	KASSERT(phw->phw_pmc == NULL,
327 	    ("[soft,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
328 
329 	ev = pmc->pm_event;
330 
331 	/* Check if event is registered. */
332 	ps = pmc_soft_ev_acquire(ev);
333 	KASSERT(ps != NULL,
334 	    ("[soft,%d] unregistered event %d", __LINE__, ev));
335 	pmc_soft_ev_release(ps);
336 	/* Module unload is protected by pmc SX lock. */
337 	if (ps->ps_release != NULL)
338 		ps->ps_release();
339 	return (0);
340 }
341 
342 static int
343 soft_start_pmc(int cpu, int ri)
344 {
345 	struct pmc *pm;
346 	struct soft_cpu *pc;
347 	struct pmc_soft *ps;
348 
349 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
350 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
351 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
352 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
353 
354 	pc = soft_pcpu[cpu];
355 	pm = pc->soft_hw[ri].phw_pmc;
356 
357 	KASSERT(pm,
358 	    ("[soft,%d] cpu %d ri %d pmc not configured", __LINE__, cpu, ri));
359 
360 	ps = pmc_soft_ev_acquire(pm->pm_event);
361 	if (ps == NULL)
362 		return (EINVAL);
363 	atomic_add_int(&ps->ps_running, 1);
364 	pmc_soft_ev_release(ps);
365 
366 	return (0);
367 }
368 
369 static int
370 soft_stop_pmc(int cpu, int ri)
371 {
372 	struct pmc *pm;
373 	struct soft_cpu *pc;
374 	struct pmc_soft *ps;
375 
376 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
377 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
378 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
379 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
380 
381 	pc = soft_pcpu[cpu];
382 	pm = pc->soft_hw[ri].phw_pmc;
383 
384 	KASSERT(pm,
385 	    ("[soft,%d] cpu %d ri %d pmc not configured", __LINE__, cpu, ri));
386 
387 	ps = pmc_soft_ev_acquire(pm->pm_event);
388 	/* event unregistered ? */
389 	if (ps != NULL) {
390 		atomic_subtract_int(&ps->ps_running, 1);
391 		pmc_soft_ev_release(ps);
392 	}
393 
394 	return (0);
395 }
396 
397 int
398 pmc_soft_intr(struct pmckern_soft *ks)
399 {
400 	struct pmc *pm;
401 	struct soft_cpu *pc;
402 	int ri, processed, error, user_mode;
403 
404 	KASSERT(ks->pm_cpu >= 0 && ks->pm_cpu < pmc_cpu_max(),
405 	    ("[soft,%d] CPU %d out of range", __LINE__, ks->pm_cpu));
406 
407 	processed = 0;
408 	pc = soft_pcpu[ks->pm_cpu];
409 
410 	for (ri = 0; ri < SOFT_NPMCS; ri++) {
411 
412 		pm = pc->soft_hw[ri].phw_pmc;
413 		if (pm == NULL ||
414 		    pm->pm_state != PMC_STATE_RUNNING ||
415 		    pm->pm_event != ks->pm_ev) {
416 				continue;
417 		}
418 
419 		processed = 1;
420 		if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
421 			if ((pc->soft_values[ri]--) <= 0)
422 				pc->soft_values[ri] += pm->pm_sc.pm_reloadcount;
423 			else
424 				continue;
425 			user_mode = TRAPF_USERMODE(ks->pm_tf);
426 			error = pmc_process_interrupt(PMC_SR, pm, ks->pm_tf);
427 			if (error) {
428 				soft_stop_pmc(ks->pm_cpu, ri);
429 				continue;
430 			}
431 
432 			if (user_mode) {
433 				/*
434 				 * If in user mode setup AST to process
435 				 * callchain out of interrupt context.
436 				 */
437 				ast_sched(curthread, TDA_HWPMC);
438 			}
439 		} else
440 			pc->soft_values[ri]++;
441 	}
442 	if (processed)
443 		counter_u64_add(pmc_stats.pm_intr_processed, 1);
444 	else
445 		counter_u64_add(pmc_stats.pm_intr_ignored, 1);
446 
447 	return (processed);
448 }
449 
450 static void
451 ast_hwpmc(struct thread *td, int tda __unused)
452 {
453 	/* Handle Software PMC callchain capture. */
454 	if (PMC_IS_PENDING_CALLCHAIN(td))
455 		PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_USER_CALLCHAIN_SOFT,
456 		    (void *)td->td_frame);
457 }
458 
459 void
460 pmc_soft_initialize(struct pmc_mdep *md)
461 {
462 	struct pmc_classdep *pcd;
463 
464 	/* Add SOFT PMCs. */
465 	soft_pcpu = malloc(sizeof(struct soft_cpu *) * pmc_cpu_max(), M_PMC,
466 	    M_ZERO|M_WAITOK);
467 
468 	pcd = &md->pmd_classdep[PMC_CLASS_INDEX_SOFT];
469 
470 	pcd->pcd_caps	= SOFT_CAPS;
471 	pcd->pcd_class	= PMC_CLASS_SOFT;
472 	pcd->pcd_num	= SOFT_NPMCS;
473 	pcd->pcd_ri	= md->pmd_npmc;
474 	pcd->pcd_width	= 64;
475 
476 	pcd->pcd_allocate_pmc = soft_allocate_pmc;
477 	pcd->pcd_config_pmc   = soft_config_pmc;
478 	pcd->pcd_describe     = soft_describe;
479 	pcd->pcd_get_config   = soft_get_config;
480 	pcd->pcd_get_msr      = NULL;
481 	pcd->pcd_pcpu_init    = soft_pcpu_init;
482 	pcd->pcd_pcpu_fini    = soft_pcpu_fini;
483 	pcd->pcd_read_pmc     = soft_read_pmc;
484 	pcd->pcd_write_pmc    = soft_write_pmc;
485 	pcd->pcd_release_pmc  = soft_release_pmc;
486 	pcd->pcd_start_pmc    = soft_start_pmc;
487 	pcd->pcd_stop_pmc     = soft_stop_pmc;
488 
489 	md->pmd_npmc += SOFT_NPMCS;
490 
491 	ast_register(TDA_HWPMC, ASTR_UNCOND, 0, ast_hwpmc);
492 }
493 
494 void
495 pmc_soft_finalize(struct pmc_mdep *md)
496 {
497 #ifdef	INVARIANTS
498 	int i, ncpus;
499 
500 	ncpus = pmc_cpu_max();
501 	for (i = 0; i < ncpus; i++)
502 		KASSERT(soft_pcpu[i] == NULL, ("[soft,%d] non-null pcpu cpu %d",
503 		    __LINE__, i));
504 
505 	KASSERT(md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_class ==
506 	    PMC_CLASS_SOFT, ("[soft,%d] class mismatch", __LINE__));
507 #endif
508 	ast_deregister(TDA_HWPMC);
509 	free(soft_pcpu, M_PMC);
510 	soft_pcpu = NULL;
511 }
512