xref: /freebsd/sys/dev/hwpmc/hwpmc_soft.c (revision f5463265955b829775bbb32e1fd0bc11dafc36ce)
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/param.h>
30 #include <sys/pmc.h>
31 #include <sys/pmckern.h>
32 #include <sys/systm.h>
33 #include <sys/mutex.h>
34 
35 #include <machine/cpu.h>
36 #include <machine/cpufunc.h>
37 
38 #include "hwpmc_soft.h"
39 
40 /*
41  * Software PMC support.
42  */
43 
44 #define	SOFT_CAPS (PMC_CAP_READ | PMC_CAP_WRITE | PMC_CAP_INTERRUPT | \
45     PMC_CAP_USER | PMC_CAP_SYSTEM)
46 
47 struct soft_descr {
48 	struct pmc_descr pm_descr;  /* "base class" */
49 };
50 
51 static struct soft_descr soft_pmcdesc[SOFT_NPMCS] =
52 {
53 #define	SOFT_PMCDESCR(N)				\
54 	{						\
55 		.pm_descr =				\
56 		{					\
57 			.pd_name = #N,			\
58 			.pd_class = PMC_CLASS_SOFT,	\
59 			.pd_caps = SOFT_CAPS,		\
60 			.pd_width = 64			\
61 		},					\
62 	}
63 
64 	SOFT_PMCDESCR(SOFT0),
65 	SOFT_PMCDESCR(SOFT1),
66 	SOFT_PMCDESCR(SOFT2),
67 	SOFT_PMCDESCR(SOFT3),
68 	SOFT_PMCDESCR(SOFT4),
69 	SOFT_PMCDESCR(SOFT5),
70 	SOFT_PMCDESCR(SOFT6),
71 	SOFT_PMCDESCR(SOFT7),
72 	SOFT_PMCDESCR(SOFT8),
73 	SOFT_PMCDESCR(SOFT9),
74 	SOFT_PMCDESCR(SOFT10),
75 	SOFT_PMCDESCR(SOFT11),
76 	SOFT_PMCDESCR(SOFT12),
77 	SOFT_PMCDESCR(SOFT13),
78 	SOFT_PMCDESCR(SOFT14),
79 	SOFT_PMCDESCR(SOFT15)
80 };
81 
82 /*
83  * Per-CPU data structure.
84  */
85 
86 struct soft_cpu {
87 	struct pmc_hw	soft_hw[SOFT_NPMCS];
88 	pmc_value_t	soft_values[SOFT_NPMCS];
89 };
90 
91 
92 static struct soft_cpu **soft_pcpu;
93 
94 static int
95 soft_allocate_pmc(int cpu, int ri, struct pmc *pm,
96     const struct pmc_op_pmcallocate *a)
97 {
98 	enum pmc_event ev;
99 	struct pmc_soft *ps;
100 
101 	(void) cpu;
102 
103 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
104 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
105 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
106 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
107 
108 	if (a->pm_class != PMC_CLASS_SOFT)
109 		return (EINVAL);
110 
111 	if ((pm->pm_caps & SOFT_CAPS) == 0)
112 		return (EINVAL);
113 
114 	if ((pm->pm_caps & ~SOFT_CAPS) != 0)
115 		return (EPERM);
116 
117 	ev = pm->pm_event;
118 	if ((int)ev < PMC_EV_SOFT_FIRST || (int)ev > PMC_EV_SOFT_LAST)
119 		return (EINVAL);
120 
121 	/* Check if event is registered. */
122 	ps = pmc_soft_ev_acquire(ev);
123 	if (ps == NULL)
124 		return (EINVAL);
125 	pmc_soft_ev_release(ps);
126 	/* Module unload is protected by pmc SX lock. */
127 	if (ps->ps_alloc != NULL)
128 		ps->ps_alloc();
129 
130 	return (0);
131 }
132 
133 static int
134 soft_config_pmc(int cpu, int ri, struct pmc *pm)
135 {
136 	struct pmc_hw *phw;
137 
138 	PMCDBG3(MDP,CFG,1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
139 
140 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
141 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
142 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
143 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
144 
145 	phw = &soft_pcpu[cpu]->soft_hw[ri];
146 
147 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
148 	    ("[soft,%d] pm=%p phw->pm=%p hwpmc not unconfigured", __LINE__,
149 	    pm, phw->phw_pmc));
150 
151 	phw->phw_pmc = pm;
152 
153 	return (0);
154 }
155 
156 static int
157 soft_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
158 {
159 	const struct soft_descr *pd;
160 	struct pmc_hw *phw;
161 
162 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
163 	    ("[soft,%d] illegal CPU %d", __LINE__, cpu));
164 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
165 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
166 
167 	phw = &soft_pcpu[cpu]->soft_hw[ri];
168 	pd  = &soft_pmcdesc[ri];
169 
170 	strlcpy(pi->pm_name, pd->pm_descr.pd_name, sizeof(pi->pm_name));
171 	pi->pm_class = pd->pm_descr.pd_class;
172 
173 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
174 		pi->pm_enabled = TRUE;
175 		*ppmc          = phw->phw_pmc;
176 	} else {
177 		pi->pm_enabled = FALSE;
178 		*ppmc          = NULL;
179 	}
180 
181 	return (0);
182 }
183 
184 static int
185 soft_get_config(int cpu, int ri, struct pmc **ppm)
186 {
187 	(void) ri;
188 
189 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
190 	    ("[soft,%d] illegal CPU %d", __LINE__, cpu));
191 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
192 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
193 
194 	*ppm = soft_pcpu[cpu]->soft_hw[ri].phw_pmc;
195 	return (0);
196 }
197 
198 static int
199 soft_pcpu_fini(struct pmc_mdep *md, int cpu)
200 {
201 	int ri;
202 	struct pmc_cpu *pc;
203 
204 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
205 	    ("[soft,%d] illegal cpu %d", __LINE__, cpu));
206 	KASSERT(soft_pcpu[cpu] != NULL, ("[soft,%d] null pcpu", __LINE__));
207 
208 	free(soft_pcpu[cpu], M_PMC);
209 	soft_pcpu[cpu] = NULL;
210 
211 	ri = md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_ri;
212 
213 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
214 	    ("[soft,%d] ri=%d", __LINE__, ri));
215 
216 	pc = pmc_pcpu[cpu];
217 	pc->pc_hwpmcs[ri] = NULL;
218 
219 	return (0);
220 }
221 
222 static int
223 soft_pcpu_init(struct pmc_mdep *md, int cpu)
224 {
225 	int first_ri, n;
226 	struct pmc_cpu *pc;
227 	struct soft_cpu *soft_pc;
228 	struct pmc_hw *phw;
229 
230 
231 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
232 	    ("[soft,%d] illegal cpu %d", __LINE__, cpu));
233 	KASSERT(soft_pcpu, ("[soft,%d] null pcpu", __LINE__));
234 	KASSERT(soft_pcpu[cpu] == NULL, ("[soft,%d] non-null per-cpu",
235 	    __LINE__));
236 
237 	soft_pc = malloc(sizeof(struct soft_cpu), M_PMC, M_WAITOK|M_ZERO);
238 	pc = pmc_pcpu[cpu];
239 
240 	KASSERT(pc != NULL, ("[soft,%d] cpu %d null per-cpu", __LINE__, cpu));
241 
242 	soft_pcpu[cpu] = soft_pc;
243 	phw = soft_pc->soft_hw;
244 	first_ri = md->pmd_classdep[PMC_CLASS_INDEX_SOFT].pcd_ri;
245 
246 	for (n = 0; n < SOFT_NPMCS; n++, phw++) {
247 		phw->phw_state = PMC_PHW_FLAG_IS_ENABLED |
248 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(n);
249 		phw->phw_pmc = NULL;
250 		pc->pc_hwpmcs[n + first_ri] = phw;
251 	}
252 
253 	return (0);
254 }
255 
256 static int
257 soft_read_pmc(int cpu, int ri, struct pmc *pm __unused, pmc_value_t *v)
258 {
259 
260 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
261 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
262 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
263 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
264 
265 	PMCDBG1(MDP,REA,1,"soft-read id=%d", ri);
266 
267 	*v = soft_pcpu[cpu]->soft_values[ri];
268 
269 	return (0);
270 }
271 
272 static int
273 soft_write_pmc(int cpu, int ri, struct pmc *pm __unused, pmc_value_t v)
274 {
275 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
276 	    ("[soft,%d] illegal cpu value %d", __LINE__, cpu));
277 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
278 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
279 
280 	PMCDBG3(MDP,WRI,1, "soft-write cpu=%d ri=%d v=%jx", cpu, ri, v);
281 
282 	soft_pcpu[cpu]->soft_values[ri] = v;
283 
284 	return (0);
285 }
286 
287 static int
288 soft_release_pmc(int cpu, int ri, struct pmc *pmc)
289 {
290 	struct pmc_hw *phw __diagused;
291 	enum pmc_event ev;
292 	struct pmc_soft *ps;
293 
294 	(void) pmc;
295 
296 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
297 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
298 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
299 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
300 
301 	phw = &soft_pcpu[cpu]->soft_hw[ri];
302 
303 	KASSERT(phw->phw_pmc == NULL,
304 	    ("[soft,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
305 
306 	ev = pmc->pm_event;
307 
308 	/* Check if event is registered. */
309 	ps = pmc_soft_ev_acquire(ev);
310 	KASSERT(ps != NULL,
311 	    ("[soft,%d] unregistered event %d", __LINE__, ev));
312 	pmc_soft_ev_release(ps);
313 	/* Module unload is protected by pmc SX lock. */
314 	if (ps->ps_release != NULL)
315 		ps->ps_release();
316 	return (0);
317 }
318 
319 static int
320 soft_start_pmc(int cpu, int ri, struct pmc *pm)
321 {
322 	struct pmc_soft *ps;
323 
324 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
325 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
326 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
327 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
328 
329 	ps = pmc_soft_ev_acquire(pm->pm_event);
330 	if (ps == NULL)
331 		return (EINVAL);
332 	atomic_add_int(&ps->ps_running, 1);
333 	pmc_soft_ev_release(ps);
334 
335 	return (0);
336 }
337 
338 static int
339 soft_stop_pmc(int cpu, int ri, struct pmc *pm)
340 {
341 	struct pmc_soft *ps;
342 
343 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
344 	    ("[soft,%d] illegal CPU value %d", __LINE__, cpu));
345 	KASSERT(ri >= 0 && ri < SOFT_NPMCS,
346 	    ("[soft,%d] illegal row-index %d", __LINE__, ri));
347 
348 	ps = pmc_soft_ev_acquire(pm->pm_event);
349 	/* event unregistered ? */
350 	if (ps != NULL) {
351 		atomic_subtract_int(&ps->ps_running, 1);
352 		pmc_soft_ev_release(ps);
353 	}
354 
355 	return (0);
356 }
357 
358 int
359 pmc_soft_intr(struct pmckern_soft *ks)
360 {
361 	struct pmc *pm;
362 	struct soft_cpu *pc;
363 	int ri, processed, error, user_mode;
364 
365 	KASSERT(ks->pm_cpu >= 0 && ks->pm_cpu < pmc_cpu_max(),
366 	    ("[soft,%d] CPU %d out of range", __LINE__, ks->pm_cpu));
367 
368 	processed = 0;
369 	pc = soft_pcpu[ks->pm_cpu];
370 
371 	for (ri = 0; ri < SOFT_NPMCS; ri++) {
372 
373 		pm = pc->soft_hw[ri].phw_pmc;
374 		if (pm == NULL ||
375 		    pm->pm_state != PMC_STATE_RUNNING ||
376 		    pm->pm_event != ks->pm_ev) {
377 				continue;
378 		}
379 
380 		processed = 1;
381 		if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
382 			if ((pc->soft_values[ri]--) <= 0)
383 				pc->soft_values[ri] += pm->pm_sc.pm_reloadcount;
384 			else
385 				continue;
386 			user_mode = TRAPF_USERMODE(ks->pm_tf);
387 			error = pmc_process_interrupt(PMC_SR, pm, ks->pm_tf);
388 			if (error) {
389 				soft_stop_pmc(ks->pm_cpu, ri, pm);
390 				continue;
391 			}
392 
393 			if (user_mode) {
394 				/*
395 				 * If in user mode setup AST to process
396 				 * callchain out of interrupt context.
397 				 */
398 				ast_sched(curthread, TDA_HWPMC);
399 			}
400 		} else
401 			pc->soft_values[ri]++;
402 	}
403 	if (processed)
404 		counter_u64_add(pmc_stats.pm_intr_processed, 1);
405 	else
406 		counter_u64_add(pmc_stats.pm_intr_ignored, 1);
407 
408 	return (processed);
409 }
410 
411 static void
412 ast_hwpmc(struct thread *td, int tda __unused)
413 {
414 	/* Handle Software PMC callchain capture. */
415 	if (PMC_IS_PENDING_CALLCHAIN(td))
416 		PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_USER_CALLCHAIN_SOFT,
417 		    (void *)td->td_frame);
418 }
419 
420 void
421 pmc_soft_initialize(struct pmc_mdep *md)
422 {
423 	struct pmc_classdep *pcd;
424 
425 	/* Add SOFT PMCs. */
426 	soft_pcpu = malloc(sizeof(struct soft_cpu *) * pmc_cpu_max(), M_PMC,
427 	    M_ZERO|M_WAITOK);
428 
429 	pcd = &md->pmd_classdep[PMC_CLASS_INDEX_SOFT];
430 
431 	pcd->pcd_caps	= SOFT_CAPS;
432 	pcd->pcd_class	= PMC_CLASS_SOFT;
433 	pcd->pcd_num	= SOFT_NPMCS;
434 	pcd->pcd_ri	= md->pmd_npmc;
435 	pcd->pcd_width	= 64;
436 
437 	pcd->pcd_allocate_pmc = soft_allocate_pmc;
438 	pcd->pcd_config_pmc   = soft_config_pmc;
439 	pcd->pcd_describe     = soft_describe;
440 	pcd->pcd_get_config   = soft_get_config;
441 	pcd->pcd_get_msr      = NULL;
442 	pcd->pcd_pcpu_init    = soft_pcpu_init;
443 	pcd->pcd_pcpu_fini    = soft_pcpu_fini;
444 	pcd->pcd_read_pmc     = soft_read_pmc;
445 	pcd->pcd_write_pmc    = soft_write_pmc;
446 	pcd->pcd_release_pmc  = soft_release_pmc;
447 	pcd->pcd_start_pmc    = soft_start_pmc;
448 	pcd->pcd_stop_pmc     = soft_stop_pmc;
449 
450 	md->pmd_npmc += SOFT_NPMCS;
451 
452 	ast_register(TDA_HWPMC, ASTR_UNCOND, 0, ast_hwpmc);
453 }
454 
455 void
456 pmc_soft_finalize(struct pmc_mdep *md)
457 {
458 	PMCDBG0(MDP, INI, 1, "soft-finalize");
459 
460 	for (int i = 0; i < pmc_cpu_max(); i++)
461 		KASSERT(soft_pcpu[i] == NULL, ("[soft,%d] non-null pcpu cpu %d",
462 		    __LINE__, i));
463 
464 	ast_deregister(TDA_HWPMC);
465 	free(soft_pcpu, M_PMC);
466 	soft_pcpu = NULL;
467 }
468