xref: /freebsd/sys/dev/hwpmc/hwpmc_soft.c (revision 2ff63af9b88c7413b7d71715b5532625752a248e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 	const struct soft_descr *pd;
163 	struct pmc_hw *phw;
164 
165 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
166 	    ("[soft,%d] illegal CPU %d", __LINE__, cpu));
167 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
168 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
169 
170 	phw = &soft_pcpu[cpu]->soft_hw[ri];
171 	pd  = &soft_pmcdesc[ri];
172 
173 	strlcpy(pi->pm_name, pd->pm_descr.pd_name, sizeof(pi->pm_name));
174 	pi->pm_class = pd->pm_descr.pd_class;
175 
176 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
177 		pi->pm_enabled = TRUE;
178 		*ppmc          = phw->phw_pmc;
179 	} else {
180 		pi->pm_enabled = FALSE;
181 		*ppmc          = NULL;
182 	}
183 
184 	return (0);
185 }
186 
187 static int
188 soft_get_config(int cpu, int ri, struct pmc **ppm)
189 {
190 	(void) ri;
191 
192 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
193 	    ("[soft,%d] illegal CPU %d", __LINE__, cpu));
194 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
195 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
196 
197 	*ppm = soft_pcpu[cpu]->soft_hw[ri].phw_pmc;
198 	return (0);
199 }
200 
201 static int
202 soft_pcpu_fini(struct pmc_mdep *md, int cpu)
203 {
204 	int ri;
205 	struct pmc_cpu *pc;
206 
207 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
208 	    ("[soft,%d] illegal cpu %d", __LINE__, cpu));
209 	KASSERT(soft_pcpu[cpu] != NULL, ("[soft,%d] null pcpu", __LINE__));
210 
211 	free(soft_pcpu[cpu], M_PMC);
212 	soft_pcpu[cpu] = NULL;
213 
214 	ri = md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_ri;
215 
216 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
217 	    ("[soft,%d] ri=%d", __LINE__, ri));
218 
219 	pc = pmc_pcpu[cpu];
220 	pc->pc_hwpmcs[ri] = NULL;
221 
222 	return (0);
223 }
224 
225 static int
226 soft_pcpu_init(struct pmc_mdep *md, int cpu)
227 {
228 	int first_ri, n;
229 	struct pmc_cpu *pc;
230 	struct soft_cpu *soft_pc;
231 	struct pmc_hw *phw;
232 
233 
234 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
235 	    ("[soft,%d] illegal cpu %d", __LINE__, cpu));
236 	KASSERT(soft_pcpu, ("[soft,%d] null pcpu", __LINE__));
237 	KASSERT(soft_pcpu[cpu] == NULL, ("[soft,%d] non-null per-cpu",
238 	    __LINE__));
239 
240 	soft_pc = malloc(sizeof(struct soft_cpu), M_PMC, M_WAITOK|M_ZERO);
241 	pc = pmc_pcpu[cpu];
242 
243 	KASSERT(pc != NULL, ("[soft,%d] cpu %d null per-cpu", __LINE__, cpu));
244 
245 	soft_pcpu[cpu] = soft_pc;
246 	phw = soft_pc->soft_hw;
247 	first_ri = md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_ri;
248 
249 	for (n = 0; n < SOFT_NPMCS; n++, phw++) {
250 		phw->phw_state = PMC_PHW_FLAG_IS_ENABLED |
251 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(n);
252 		phw->phw_pmc = NULL;
253 		pc->pc_hwpmcs[n + first_ri] = phw;
254 	}
255 
256 	return (0);
257 }
258 
259 static int
260 soft_read_pmc(int cpu, int ri, struct pmc *pm __unused, pmc_value_t *v)
261 {
262 
263 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
264 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
265 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
266 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
267 
268 	PMCDBG1(MDP,REA,1,"soft-read id=%d", ri);
269 
270 	*v = soft_pcpu[cpu]->soft_values[ri];
271 
272 	return (0);
273 }
274 
275 static int
276 soft_write_pmc(int cpu, int ri, struct pmc *pm __unused, pmc_value_t v)
277 {
278 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
279 	    ("[soft,%d] illegal cpu value %d", __LINE__, cpu));
280 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
281 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
282 
283 	PMCDBG3(MDP,WRI,1, "soft-write cpu=%d ri=%d v=%jx", cpu, ri, v);
284 
285 	soft_pcpu[cpu]->soft_values[ri] = v;
286 
287 	return (0);
288 }
289 
290 static int
291 soft_release_pmc(int cpu, int ri, struct pmc *pmc)
292 {
293 	struct pmc_hw *phw __diagused;
294 	enum pmc_event ev;
295 	struct pmc_soft *ps;
296 
297 	(void) pmc;
298 
299 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
300 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
301 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
302 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
303 
304 	phw = &soft_pcpu[cpu]->soft_hw[ri];
305 
306 	KASSERT(phw->phw_pmc == NULL,
307 	    ("[soft,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
308 
309 	ev = pmc->pm_event;
310 
311 	/* Check if event is registered. */
312 	ps = pmc_soft_ev_acquire(ev);
313 	KASSERT(ps != NULL,
314 	    ("[soft,%d] unregistered event %d", __LINE__, ev));
315 	pmc_soft_ev_release(ps);
316 	/* Module unload is protected by pmc SX lock. */
317 	if (ps->ps_release != NULL)
318 		ps->ps_release();
319 	return (0);
320 }
321 
322 static int
323 soft_start_pmc(int cpu, int ri, struct pmc *pm)
324 {
325 	struct pmc_soft *ps;
326 
327 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
328 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
329 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
330 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
331 
332 	ps = pmc_soft_ev_acquire(pm->pm_event);
333 	if (ps == NULL)
334 		return (EINVAL);
335 	atomic_add_int(&ps->ps_running, 1);
336 	pmc_soft_ev_release(ps);
337 
338 	return (0);
339 }
340 
341 static int
342 soft_stop_pmc(int cpu, int ri, struct pmc *pm)
343 {
344 	struct pmc_soft *ps;
345 
346 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
347 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
348 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
349 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
350 
351 	ps = pmc_soft_ev_acquire(pm->pm_event);
352 	/* event unregistered ? */
353 	if (ps != NULL) {
354 		atomic_subtract_int(&ps->ps_running, 1);
355 		pmc_soft_ev_release(ps);
356 	}
357 
358 	return (0);
359 }
360 
361 int
362 pmc_soft_intr(struct pmckern_soft *ks)
363 {
364 	struct pmc *pm;
365 	struct soft_cpu *pc;
366 	int ri, processed, error, user_mode;
367 
368 	KASSERT(ks->pm_cpu >= 0 && ks->pm_cpu < pmc_cpu_max(),
369 	    ("[soft,%d] CPU %d out of range", __LINE__, ks->pm_cpu));
370 
371 	processed = 0;
372 	pc = soft_pcpu[ks->pm_cpu];
373 
374 	for (ri = 0; ri < SOFT_NPMCS; ri++) {
375 
376 		pm = pc->soft_hw[ri].phw_pmc;
377 		if (pm == NULL ||
378 		    pm->pm_state != PMC_STATE_RUNNING ||
379 		    pm->pm_event != ks->pm_ev) {
380 				continue;
381 		}
382 
383 		processed = 1;
384 		if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
385 			if ((pc->soft_values[ri]--) <= 0)
386 				pc->soft_values[ri] += pm->pm_sc.pm_reloadcount;
387 			else
388 				continue;
389 			user_mode = TRAPF_USERMODE(ks->pm_tf);
390 			error = pmc_process_interrupt(PMC_SR, pm, ks->pm_tf);
391 			if (error) {
392 				soft_stop_pmc(ks->pm_cpu, ri, pm);
393 				continue;
394 			}
395 
396 			if (user_mode) {
397 				/*
398 				 * If in user mode setup AST to process
399 				 * callchain out of interrupt context.
400 				 */
401 				ast_sched(curthread, TDA_HWPMC);
402 			}
403 		} else
404 			pc->soft_values[ri]++;
405 	}
406 	if (processed)
407 		counter_u64_add(pmc_stats.pm_intr_processed, 1);
408 	else
409 		counter_u64_add(pmc_stats.pm_intr_ignored, 1);
410 
411 	return (processed);
412 }
413 
414 static void
415 ast_hwpmc(struct thread *td, int tda __unused)
416 {
417 	/* Handle Software PMC callchain capture. */
418 	if (PMC_IS_PENDING_CALLCHAIN(td))
419 		PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_USER_CALLCHAIN_SOFT,
420 		    (void *)td->td_frame);
421 }
422 
423 void
424 pmc_soft_initialize(struct pmc_mdep *md)
425 {
426 	struct pmc_classdep *pcd;
427 
428 	/* Add SOFT PMCs. */
429 	soft_pcpu = malloc(sizeof(struct soft_cpu *) * pmc_cpu_max(), M_PMC,
430 	    M_ZERO|M_WAITOK);
431 
432 	pcd = &md->pmd_classdep[PMC_CLASS_INDEX_SOFT];
433 
434 	pcd->pcd_caps	= SOFT_CAPS;
435 	pcd->pcd_class	= PMC_CLASS_SOFT;
436 	pcd->pcd_num	= SOFT_NPMCS;
437 	pcd->pcd_ri	= md->pmd_npmc;
438 	pcd->pcd_width	= 64;
439 
440 	pcd->pcd_allocate_pmc = soft_allocate_pmc;
441 	pcd->pcd_config_pmc   = soft_config_pmc;
442 	pcd->pcd_describe     = soft_describe;
443 	pcd->pcd_get_config   = soft_get_config;
444 	pcd->pcd_get_msr      = NULL;
445 	pcd->pcd_pcpu_init    = soft_pcpu_init;
446 	pcd->pcd_pcpu_fini    = soft_pcpu_fini;
447 	pcd->pcd_read_pmc     = soft_read_pmc;
448 	pcd->pcd_write_pmc    = soft_write_pmc;
449 	pcd->pcd_release_pmc  = soft_release_pmc;
450 	pcd->pcd_start_pmc    = soft_start_pmc;
451 	pcd->pcd_stop_pmc     = soft_stop_pmc;
452 
453 	md->pmd_npmc += SOFT_NPMCS;
454 
455 	ast_register(TDA_HWPMC, ASTR_UNCOND, 0, ast_hwpmc);
456 }
457 
458 void
459 pmc_soft_finalize(struct pmc_mdep *md)
460 {
461 #ifdef	INVARIANTS
462 	int i, ncpus;
463 
464 	ncpus = pmc_cpu_max();
465 	for (i = 0; i < ncpus; i++)
466 		KASSERT(soft_pcpu[i] == NULL, ("[soft,%d] non-null pcpu cpu %d",
467 		    __LINE__, i));
468 
469 	KASSERT(md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_class ==
470 	    PMC_CLASS_SOFT, ("[soft,%d] class mismatch", __LINE__));
471 #endif
472 	ast_deregister(TDA_HWPMC);
473 	free(soft_pcpu, M_PMC);
474 	soft_pcpu = NULL;
475 }
476