xref: /freebsd/sys/dev/hwpmc/hwpmc_soft.c (revision 05248206f720394d95c2a7475429311df670a2e9)
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 #include <sys/param.h>
31 #include <sys/pmc.h>
32 #include <sys/pmckern.h>
33 #include <sys/systm.h>
34 #include <sys/mutex.h>
35 
36 #include <machine/cpu.h>
37 #include <machine/cpufunc.h>
38 
39 #include "hwpmc_soft.h"
40 
41 /*
42  * Software PMC support.
43  */
44 
45 #define	SOFT_CAPS (PMC_CAP_READ | PMC_CAP_WRITE | PMC_CAP_INTERRUPT | \
46     PMC_CAP_USER | PMC_CAP_SYSTEM)
47 
48 struct soft_descr {
49 	struct pmc_descr pm_descr;  /* "base class" */
50 };
51 
52 static struct soft_descr soft_pmcdesc[SOFT_NPMCS] =
53 {
54 #define	SOFT_PMCDESCR(N)				\
55 	{						\
56 		.pm_descr =				\
57 		{					\
58 			.pd_name = #N,			\
59 			.pd_class = PMC_CLASS_SOFT,	\
60 			.pd_caps = SOFT_CAPS,		\
61 			.pd_width = 64			\
62 		},					\
63 	}
64 
65 	SOFT_PMCDESCR(SOFT0),
66 	SOFT_PMCDESCR(SOFT1),
67 	SOFT_PMCDESCR(SOFT2),
68 	SOFT_PMCDESCR(SOFT3),
69 	SOFT_PMCDESCR(SOFT4),
70 	SOFT_PMCDESCR(SOFT5),
71 	SOFT_PMCDESCR(SOFT6),
72 	SOFT_PMCDESCR(SOFT7),
73 	SOFT_PMCDESCR(SOFT8),
74 	SOFT_PMCDESCR(SOFT9),
75 	SOFT_PMCDESCR(SOFT10),
76 	SOFT_PMCDESCR(SOFT11),
77 	SOFT_PMCDESCR(SOFT12),
78 	SOFT_PMCDESCR(SOFT13),
79 	SOFT_PMCDESCR(SOFT14),
80 	SOFT_PMCDESCR(SOFT15)
81 };
82 
83 /*
84  * Per-CPU data structure.
85  */
86 
87 struct soft_cpu {
88 	struct pmc_hw	soft_hw[SOFT_NPMCS];
89 	pmc_value_t	soft_values[SOFT_NPMCS];
90 };
91 
92 
93 static struct soft_cpu **soft_pcpu;
94 
95 static int
96 soft_allocate_pmc(int cpu, int ri, struct pmc *pm,
97     const struct pmc_op_pmcallocate *a)
98 {
99 	enum pmc_event ev;
100 	struct pmc_soft *ps;
101 
102 	(void) cpu;
103 
104 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
105 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
106 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
107 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
108 
109 	if (a->pm_class != PMC_CLASS_SOFT)
110 		return (EINVAL);
111 
112 	if ((pm->pm_caps & SOFT_CAPS) == 0)
113 		return (EINVAL);
114 
115 	if ((pm->pm_caps & ~SOFT_CAPS) != 0)
116 		return (EPERM);
117 
118 	ev = pm->pm_event;
119 	if ((int)ev < PMC_EV_SOFT_FIRST || (int)ev > PMC_EV_SOFT_LAST)
120 		return (EINVAL);
121 
122 	/* Check if event is registered. */
123 	ps = pmc_soft_ev_acquire(ev);
124 	if (ps == NULL)
125 		return (EINVAL);
126 	pmc_soft_ev_release(ps);
127 	/* Module unload is protected by pmc SX lock. */
128 	if (ps->ps_alloc != NULL)
129 		ps->ps_alloc();
130 
131 	return (0);
132 }
133 
134 static int
135 soft_config_pmc(int cpu, int ri, struct pmc *pm)
136 {
137 	struct pmc_hw *phw;
138 
139 	PMCDBG3(MDP,CFG,1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
140 
141 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
142 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
143 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
144 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
145 
146 	phw = &soft_pcpu[cpu]->soft_hw[ri];
147 
148 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
149 	    ("[soft,%d] pm=%p phw->pm=%p hwpmc not unconfigured", __LINE__,
150 	    pm, phw->phw_pmc));
151 
152 	phw->phw_pmc = pm;
153 
154 	return (0);
155 }
156 
157 static int
158 soft_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
159 {
160 	const struct soft_descr *pd;
161 	struct pmc_hw *phw;
162 
163 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
164 	    ("[soft,%d] illegal CPU %d", __LINE__, cpu));
165 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
166 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
167 
168 	phw = &soft_pcpu[cpu]->soft_hw[ri];
169 	pd  = &soft_pmcdesc[ri];
170 
171 	strlcpy(pi->pm_name, pd->pm_descr.pd_name, sizeof(pi->pm_name));
172 	pi->pm_class = pd->pm_descr.pd_class;
173 
174 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
175 		pi->pm_enabled = TRUE;
176 		*ppmc          = phw->phw_pmc;
177 	} else {
178 		pi->pm_enabled = FALSE;
179 		*ppmc          = NULL;
180 	}
181 
182 	return (0);
183 }
184 
185 static int
186 soft_get_config(int cpu, int ri, struct pmc **ppm)
187 {
188 	(void) ri;
189 
190 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
191 	    ("[soft,%d] illegal CPU %d", __LINE__, cpu));
192 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
193 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
194 
195 	*ppm = soft_pcpu[cpu]->soft_hw[ri].phw_pmc;
196 	return (0);
197 }
198 
199 static int
200 soft_pcpu_fini(struct pmc_mdep *md, int cpu)
201 {
202 	int ri;
203 	struct pmc_cpu *pc;
204 
205 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
206 	    ("[soft,%d] illegal cpu %d", __LINE__, cpu));
207 	KASSERT(soft_pcpu[cpu] != NULL, ("[soft,%d] null pcpu", __LINE__));
208 
209 	free(soft_pcpu[cpu], M_PMC);
210 	soft_pcpu[cpu] = NULL;
211 
212 	ri = md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_ri;
213 
214 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
215 	    ("[soft,%d] ri=%d", __LINE__, ri));
216 
217 	pc = pmc_pcpu[cpu];
218 	pc->pc_hwpmcs[ri] = NULL;
219 
220 	return (0);
221 }
222 
223 static int
224 soft_pcpu_init(struct pmc_mdep *md, int cpu)
225 {
226 	int first_ri, n;
227 	struct pmc_cpu *pc;
228 	struct soft_cpu *soft_pc;
229 	struct pmc_hw *phw;
230 
231 
232 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
233 	    ("[soft,%d] illegal cpu %d", __LINE__, cpu));
234 	KASSERT(soft_pcpu, ("[soft,%d] null pcpu", __LINE__));
235 	KASSERT(soft_pcpu[cpu] == NULL, ("[soft,%d] non-null per-cpu",
236 	    __LINE__));
237 
238 	soft_pc = malloc(sizeof(struct soft_cpu), M_PMC, M_WAITOK|M_ZERO);
239 	pc = pmc_pcpu[cpu];
240 
241 	KASSERT(pc != NULL, ("[soft,%d] cpu %d null per-cpu", __LINE__, cpu));
242 
243 	soft_pcpu[cpu] = soft_pc;
244 	phw = soft_pc->soft_hw;
245 	first_ri = md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_ri;
246 
247 	for (n = 0; n < SOFT_NPMCS; n++, phw++) {
248 		phw->phw_state = PMC_PHW_FLAG_IS_ENABLED |
249 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(n);
250 		phw->phw_pmc = NULL;
251 		pc->pc_hwpmcs[n + first_ri] = phw;
252 	}
253 
254 	return (0);
255 }
256 
257 static int
258 soft_read_pmc(int cpu, int ri, struct pmc *pm __unused, pmc_value_t *v)
259 {
260 
261 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
262 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
263 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
264 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
265 
266 	PMCDBG1(MDP,REA,1,"soft-read id=%d", ri);
267 
268 	*v = soft_pcpu[cpu]->soft_values[ri];
269 
270 	return (0);
271 }
272 
273 static int
274 soft_write_pmc(int cpu, int ri, struct pmc *pm __unused, pmc_value_t v)
275 {
276 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
277 	    ("[soft,%d] illegal cpu value %d", __LINE__, cpu));
278 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
279 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
280 
281 	PMCDBG3(MDP,WRI,1, "soft-write cpu=%d ri=%d v=%jx", cpu, ri, v);
282 
283 	soft_pcpu[cpu]->soft_values[ri] = v;
284 
285 	return (0);
286 }
287 
288 static int
289 soft_release_pmc(int cpu, int ri, struct pmc *pmc)
290 {
291 	struct pmc_hw *phw __diagused;
292 	enum pmc_event ev;
293 	struct pmc_soft *ps;
294 
295 	(void) pmc;
296 
297 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
298 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
299 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
300 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
301 
302 	phw = &soft_pcpu[cpu]->soft_hw[ri];
303 
304 	KASSERT(phw->phw_pmc == NULL,
305 	    ("[soft,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
306 
307 	ev = pmc->pm_event;
308 
309 	/* Check if event is registered. */
310 	ps = pmc_soft_ev_acquire(ev);
311 	KASSERT(ps != NULL,
312 	    ("[soft,%d] unregistered event %d", __LINE__, ev));
313 	pmc_soft_ev_release(ps);
314 	/* Module unload is protected by pmc SX lock. */
315 	if (ps->ps_release != NULL)
316 		ps->ps_release();
317 	return (0);
318 }
319 
320 static int
321 soft_start_pmc(int cpu, int ri, struct pmc *pm)
322 {
323 	struct pmc_soft *ps;
324 
325 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
326 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
327 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
328 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
329 
330 	ps = pmc_soft_ev_acquire(pm->pm_event);
331 	if (ps == NULL)
332 		return (EINVAL);
333 	atomic_add_int(&ps->ps_running, 1);
334 	pmc_soft_ev_release(ps);
335 
336 	return (0);
337 }
338 
339 static int
340 soft_stop_pmc(int cpu, int ri, struct pmc *pm)
341 {
342 	struct pmc_soft *ps;
343 
344 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
345 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
346 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
347 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
348 
349 	ps = pmc_soft_ev_acquire(pm->pm_event);
350 	/* event unregistered ? */
351 	if (ps != NULL) {
352 		atomic_subtract_int(&ps->ps_running, 1);
353 		pmc_soft_ev_release(ps);
354 	}
355 
356 	return (0);
357 }
358 
359 int
360 pmc_soft_intr(struct pmckern_soft *ks)
361 {
362 	struct pmc *pm;
363 	struct soft_cpu *pc;
364 	int ri, processed, error, user_mode;
365 
366 	KASSERT(ks->pm_cpu >= 0 && ks->pm_cpu < pmc_cpu_max(),
367 	    ("[soft,%d] CPU %d out of range", __LINE__, ks->pm_cpu));
368 
369 	processed = 0;
370 	pc = soft_pcpu[ks->pm_cpu];
371 
372 	for (ri = 0; ri < SOFT_NPMCS; ri++) {
373 
374 		pm = pc->soft_hw[ri].phw_pmc;
375 		if (pm == NULL ||
376 		    pm->pm_state != PMC_STATE_RUNNING ||
377 		    pm->pm_event != ks->pm_ev) {
378 				continue;
379 		}
380 
381 		processed = 1;
382 		if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
383 			if ((pc->soft_values[ri]--) <= 0)
384 				pc->soft_values[ri] += pm->pm_sc.pm_reloadcount;
385 			else
386 				continue;
387 			user_mode = TRAPF_USERMODE(ks->pm_tf);
388 			error = pmc_process_interrupt(PMC_SR, pm, ks->pm_tf);
389 			if (error) {
390 				soft_stop_pmc(ks->pm_cpu, ri, pm);
391 				continue;
392 			}
393 
394 			if (user_mode) {
395 				/*
396 				 * If in user mode setup AST to process
397 				 * callchain out of interrupt context.
398 				 */
399 				ast_sched(curthread, TDA_HWPMC);
400 			}
401 		} else
402 			pc->soft_values[ri]++;
403 	}
404 	if (processed)
405 		counter_u64_add(pmc_stats.pm_intr_processed, 1);
406 	else
407 		counter_u64_add(pmc_stats.pm_intr_ignored, 1);
408 
409 	return (processed);
410 }
411 
412 static void
413 ast_hwpmc(struct thread *td, int tda __unused)
414 {
415 	/* Handle Software PMC callchain capture. */
416 	if (PMC_IS_PENDING_CALLCHAIN(td))
417 		PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_USER_CALLCHAIN_SOFT,
418 		    (void *)td->td_frame);
419 }
420 
421 void
422 pmc_soft_initialize(struct pmc_mdep *md)
423 {
424 	struct pmc_classdep *pcd;
425 
426 	/* Add SOFT PMCs. */
427 	soft_pcpu = malloc(sizeof(struct soft_cpu *) * pmc_cpu_max(), M_PMC,
428 	    M_ZERO|M_WAITOK);
429 
430 	pcd = &md->pmd_classdep[PMC_CLASS_INDEX_SOFT];
431 
432 	pcd->pcd_caps	= SOFT_CAPS;
433 	pcd->pcd_class	= PMC_CLASS_SOFT;
434 	pcd->pcd_num	= SOFT_NPMCS;
435 	pcd->pcd_ri	= md->pmd_npmc;
436 	pcd->pcd_width	= 64;
437 
438 	pcd->pcd_allocate_pmc = soft_allocate_pmc;
439 	pcd->pcd_config_pmc   = soft_config_pmc;
440 	pcd->pcd_describe     = soft_describe;
441 	pcd->pcd_get_config   = soft_get_config;
442 	pcd->pcd_get_msr      = NULL;
443 	pcd->pcd_pcpu_init    = soft_pcpu_init;
444 	pcd->pcd_pcpu_fini    = soft_pcpu_fini;
445 	pcd->pcd_read_pmc     = soft_read_pmc;
446 	pcd->pcd_write_pmc    = soft_write_pmc;
447 	pcd->pcd_release_pmc  = soft_release_pmc;
448 	pcd->pcd_start_pmc    = soft_start_pmc;
449 	pcd->pcd_stop_pmc     = soft_stop_pmc;
450 
451 	md->pmd_npmc += SOFT_NPMCS;
452 
453 	ast_register(TDA_HWPMC, ASTR_UNCOND, 0, ast_hwpmc);
454 }
455 
456 void
457 pmc_soft_finalize(struct pmc_mdep *md)
458 {
459 #ifdef	INVARIANTS
460 	int i, ncpus;
461 
462 	ncpus = pmc_cpu_max();
463 	for (i = 0; i < ncpus; i++)
464 		KASSERT(soft_pcpu[i] == NULL, ("[soft,%d] non-null pcpu cpu %d",
465 		    __LINE__, i));
466 
467 	KASSERT(md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_class ==
468 	    PMC_CLASS_SOFT, ("[soft,%d] class mismatch", __LINE__));
469 #endif
470 	ast_deregister(TDA_HWPMC);
471 	free(soft_pcpu, M_PMC);
472 	soft_pcpu = NULL;
473 }
474