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1// SPDX-License-Identifier: GPL-2.02#include <perf/evlist.h>3#include <perf/evsel.h>4#include <linux/bitops.h>5#include <linux/list.h>6#include <linux/hash.h>7#include <sys/ioctl.h>8#include <internal/evlist.h>9#include <internal/evsel.h>10#include <internal/xyarray.h>11#include <internal/mmap.h>12#include <internal/cpumap.h>13#include <internal/threadmap.h>14#include <internal/lib.h>15#include <linux/zalloc.h>16#include <stdlib.h>17#include <errno.h>18#include <unistd.h>19#include <fcntl.h>20#include <signal.h>21#include <poll.h>22#include <sys/mman.h>23#include <perf/cpumap.h>24#include <perf/threadmap.h>25#include <api/fd/array.h>26#include "internal.h"27 28void perf_evlist__init(struct perf_evlist *evlist)29{30	INIT_LIST_HEAD(&evlist->entries);31	evlist->nr_entries = 0;32	fdarray__init(&evlist->pollfd, 64);33	perf_evlist__reset_id_hash(evlist);34}35 36static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,37					  struct perf_evsel *evsel)38{39	if (evsel->system_wide) {40		/* System wide: set the cpu map of the evsel to all online CPUs. */41		perf_cpu_map__put(evsel->cpus);42		evsel->cpus = perf_cpu_map__new_online_cpus();43	} else if (evlist->has_user_cpus && evsel->is_pmu_core) {44		/*45		 * User requested CPUs on a core PMU, ensure the requested CPUs46		 * are valid by intersecting with those of the PMU.47		 */48		perf_cpu_map__put(evsel->cpus);49		evsel->cpus = perf_cpu_map__intersect(evlist->user_requested_cpus, evsel->own_cpus);50	} else if (!evsel->own_cpus || evlist->has_user_cpus ||51		(!evsel->requires_cpu && perf_cpu_map__has_any_cpu(evlist->user_requested_cpus))) {52		/*53		 * The PMU didn't specify a default cpu map, this isn't a core54		 * event and the user requested CPUs or the evlist user55		 * requested CPUs have the "any CPU" (aka dummy) CPU value. In56		 * which case use the user requested CPUs rather than the PMU57		 * ones.58		 */59		perf_cpu_map__put(evsel->cpus);60		evsel->cpus = perf_cpu_map__get(evlist->user_requested_cpus);61	} else if (evsel->cpus != evsel->own_cpus) {62		/*63		 * No user requested cpu map but the PMU cpu map doesn't match64		 * the evsel's. Reset it back to the PMU cpu map.65		 */66		perf_cpu_map__put(evsel->cpus);67		evsel->cpus = perf_cpu_map__get(evsel->own_cpus);68	}69 70	if (evsel->system_wide) {71		perf_thread_map__put(evsel->threads);72		evsel->threads = perf_thread_map__new_dummy();73	} else {74		perf_thread_map__put(evsel->threads);75		evsel->threads = perf_thread_map__get(evlist->threads);76	}77 78	evlist->all_cpus = perf_cpu_map__merge(evlist->all_cpus, evsel->cpus);79}80 81static void perf_evlist__propagate_maps(struct perf_evlist *evlist)82{83	struct perf_evsel *evsel;84 85	evlist->needs_map_propagation = true;86 87	perf_evlist__for_each_evsel(evlist, evsel)88		__perf_evlist__propagate_maps(evlist, evsel);89}90 91void perf_evlist__add(struct perf_evlist *evlist,92		      struct perf_evsel *evsel)93{94	evsel->idx = evlist->nr_entries;95	list_add_tail(&evsel->node, &evlist->entries);96	evlist->nr_entries += 1;97 98	if (evlist->needs_map_propagation)99		__perf_evlist__propagate_maps(evlist, evsel);100}101 102void perf_evlist__remove(struct perf_evlist *evlist,103			 struct perf_evsel *evsel)104{105	list_del_init(&evsel->node);106	evlist->nr_entries -= 1;107}108 109struct perf_evlist *perf_evlist__new(void)110{111	struct perf_evlist *evlist = zalloc(sizeof(*evlist));112 113	if (evlist != NULL)114		perf_evlist__init(evlist);115 116	return evlist;117}118 119struct perf_evsel *120perf_evlist__next(struct perf_evlist *evlist, struct perf_evsel *prev)121{122	struct perf_evsel *next;123 124	if (!prev) {125		next = list_first_entry(&evlist->entries,126					struct perf_evsel,127					node);128	} else {129		next = list_next_entry(prev, node);130	}131 132	/* Empty list is noticed here so don't need checking on entry. */133	if (&next->node == &evlist->entries)134		return NULL;135 136	return next;137}138 139static void perf_evlist__purge(struct perf_evlist *evlist)140{141	struct perf_evsel *pos, *n;142 143	perf_evlist__for_each_entry_safe(evlist, n, pos) {144		list_del_init(&pos->node);145		perf_evsel__delete(pos);146	}147 148	evlist->nr_entries = 0;149}150 151void perf_evlist__exit(struct perf_evlist *evlist)152{153	perf_cpu_map__put(evlist->user_requested_cpus);154	perf_cpu_map__put(evlist->all_cpus);155	perf_thread_map__put(evlist->threads);156	evlist->user_requested_cpus = NULL;157	evlist->all_cpus = NULL;158	evlist->threads = NULL;159	fdarray__exit(&evlist->pollfd);160}161 162void perf_evlist__delete(struct perf_evlist *evlist)163{164	if (evlist == NULL)165		return;166 167	perf_evlist__munmap(evlist);168	perf_evlist__close(evlist);169	perf_evlist__purge(evlist);170	perf_evlist__exit(evlist);171	free(evlist);172}173 174void perf_evlist__set_maps(struct perf_evlist *evlist,175			   struct perf_cpu_map *cpus,176			   struct perf_thread_map *threads)177{178	/*179	 * Allow for the possibility that one or another of the maps isn't being180	 * changed i.e. don't put it.  Note we are assuming the maps that are181	 * being applied are brand new and evlist is taking ownership of the182	 * original reference count of 1.  If that is not the case it is up to183	 * the caller to increase the reference count.184	 */185	if (cpus != evlist->user_requested_cpus) {186		perf_cpu_map__put(evlist->user_requested_cpus);187		evlist->user_requested_cpus = perf_cpu_map__get(cpus);188	}189 190	if (threads != evlist->threads) {191		perf_thread_map__put(evlist->threads);192		evlist->threads = perf_thread_map__get(threads);193	}194 195	perf_evlist__propagate_maps(evlist);196}197 198int perf_evlist__open(struct perf_evlist *evlist)199{200	struct perf_evsel *evsel;201	int err;202 203	perf_evlist__for_each_entry(evlist, evsel) {204		err = perf_evsel__open(evsel, evsel->cpus, evsel->threads);205		if (err < 0)206			goto out_err;207	}208 209	return 0;210 211out_err:212	perf_evlist__close(evlist);213	return err;214}215 216void perf_evlist__close(struct perf_evlist *evlist)217{218	struct perf_evsel *evsel;219 220	perf_evlist__for_each_entry_reverse(evlist, evsel)221		perf_evsel__close(evsel);222}223 224void perf_evlist__enable(struct perf_evlist *evlist)225{226	struct perf_evsel *evsel;227 228	perf_evlist__for_each_entry(evlist, evsel)229		perf_evsel__enable(evsel);230}231 232void perf_evlist__disable(struct perf_evlist *evlist)233{234	struct perf_evsel *evsel;235 236	perf_evlist__for_each_entry(evlist, evsel)237		perf_evsel__disable(evsel);238}239 240u64 perf_evlist__read_format(struct perf_evlist *evlist)241{242	struct perf_evsel *first = perf_evlist__first(evlist);243 244	return first->attr.read_format;245}246 247#define SID(e, x, y) xyarray__entry(e->sample_id, x, y)248 249static void perf_evlist__id_hash(struct perf_evlist *evlist,250				 struct perf_evsel *evsel,251				 int cpu_map_idx, int thread, u64 id)252{253	int hash;254	struct perf_sample_id *sid = SID(evsel, cpu_map_idx, thread);255 256	sid->id = id;257	sid->evsel = evsel;258	hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);259	hlist_add_head(&sid->node, &evlist->heads[hash]);260}261 262void perf_evlist__reset_id_hash(struct perf_evlist *evlist)263{264	int i;265 266	for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)267		INIT_HLIST_HEAD(&evlist->heads[i]);268}269 270void perf_evlist__id_add(struct perf_evlist *evlist,271			 struct perf_evsel *evsel,272			 int cpu_map_idx, int thread, u64 id)273{274	if (!SID(evsel, cpu_map_idx, thread))275		return;276 277	perf_evlist__id_hash(evlist, evsel, cpu_map_idx, thread, id);278	evsel->id[evsel->ids++] = id;279}280 281int perf_evlist__id_add_fd(struct perf_evlist *evlist,282			   struct perf_evsel *evsel,283			   int cpu_map_idx, int thread, int fd)284{285	u64 read_data[4] = { 0, };286	int id_idx = 1; /* The first entry is the counter value */287	u64 id;288	int ret;289 290	if (!SID(evsel, cpu_map_idx, thread))291		return -1;292 293	ret = ioctl(fd, PERF_EVENT_IOC_ID, &id);294	if (!ret)295		goto add;296 297	if (errno != ENOTTY)298		return -1;299 300	/* Legacy way to get event id.. All hail to old kernels! */301 302	/*303	 * This way does not work with group format read, so bail304	 * out in that case.305	 */306	if (perf_evlist__read_format(evlist) & PERF_FORMAT_GROUP)307		return -1;308 309	if (!(evsel->attr.read_format & PERF_FORMAT_ID) ||310	    read(fd, &read_data, sizeof(read_data)) == -1)311		return -1;312 313	if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)314		++id_idx;315	if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)316		++id_idx;317 318	id = read_data[id_idx];319 320add:321	perf_evlist__id_add(evlist, evsel, cpu_map_idx, thread, id);322	return 0;323}324 325int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)326{327	int nr_cpus = perf_cpu_map__nr(evlist->all_cpus);328	int nr_threads = perf_thread_map__nr(evlist->threads);329	int nfds = 0;330	struct perf_evsel *evsel;331 332	perf_evlist__for_each_entry(evlist, evsel) {333		if (evsel->system_wide)334			nfds += nr_cpus;335		else336			nfds += nr_cpus * nr_threads;337	}338 339	if (fdarray__available_entries(&evlist->pollfd) < nfds &&340	    fdarray__grow(&evlist->pollfd, nfds) < 0)341		return -ENOMEM;342 343	return 0;344}345 346int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd,347			    void *ptr, short revent, enum fdarray_flags flags)348{349	int pos = fdarray__add(&evlist->pollfd, fd, revent | POLLERR | POLLHUP, flags);350 351	if (pos >= 0) {352		evlist->pollfd.priv[pos].ptr = ptr;353		fcntl(fd, F_SETFL, O_NONBLOCK);354	}355 356	return pos;357}358 359static void perf_evlist__munmap_filtered(struct fdarray *fda, int fd,360					 void *arg __maybe_unused)361{362	struct perf_mmap *map = fda->priv[fd].ptr;363 364	if (map)365		perf_mmap__put(map);366}367 368int perf_evlist__filter_pollfd(struct perf_evlist *evlist, short revents_and_mask)369{370	return fdarray__filter(&evlist->pollfd, revents_and_mask,371			       perf_evlist__munmap_filtered, NULL);372}373 374int perf_evlist__poll(struct perf_evlist *evlist, int timeout)375{376	return fdarray__poll(&evlist->pollfd, timeout);377}378 379static struct perf_mmap* perf_evlist__alloc_mmap(struct perf_evlist *evlist, bool overwrite)380{381	int i;382	struct perf_mmap *map;383 384	map = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));385	if (!map)386		return NULL;387 388	for (i = 0; i < evlist->nr_mmaps; i++) {389		struct perf_mmap *prev = i ? &map[i - 1] : NULL;390 391		/*392		 * When the perf_mmap() call is made we grab one refcount, plus393		 * one extra to let perf_mmap__consume() get the last394		 * events after all real references (perf_mmap__get()) are395		 * dropped.396		 *397		 * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and398		 * thus does perf_mmap__get() on it.399		 */400		perf_mmap__init(&map[i], prev, overwrite, NULL);401	}402 403	return map;404}405 406static void perf_evsel__set_sid_idx(struct perf_evsel *evsel, int idx, int cpu, int thread)407{408	struct perf_sample_id *sid = SID(evsel, cpu, thread);409 410	sid->idx = idx;411	sid->cpu = perf_cpu_map__cpu(evsel->cpus, cpu);412	sid->tid = perf_thread_map__pid(evsel->threads, thread);413}414 415static struct perf_mmap*416perf_evlist__mmap_cb_get(struct perf_evlist *evlist, bool overwrite, int idx)417{418	struct perf_mmap *maps;419 420	maps = overwrite ? evlist->mmap_ovw : evlist->mmap;421 422	if (!maps) {423		maps = perf_evlist__alloc_mmap(evlist, overwrite);424		if (!maps)425			return NULL;426 427		if (overwrite)428			evlist->mmap_ovw = maps;429		else430			evlist->mmap = maps;431	}432 433	return &maps[idx];434}435 436#define FD(e, x, y) (*(int *) xyarray__entry(e->fd, x, y))437 438static int439perf_evlist__mmap_cb_mmap(struct perf_mmap *map, struct perf_mmap_param *mp,440			  int output, struct perf_cpu cpu)441{442	return perf_mmap__mmap(map, mp, output, cpu);443}444 445static void perf_evlist__set_mmap_first(struct perf_evlist *evlist, struct perf_mmap *map,446					bool overwrite)447{448	if (overwrite)449		evlist->mmap_ovw_first = map;450	else451		evlist->mmap_first = map;452}453 454static int455mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,456	       int idx, struct perf_mmap_param *mp, int cpu_idx,457	       int thread, int *_output, int *_output_overwrite, int *nr_mmaps)458{459	struct perf_cpu evlist_cpu = perf_cpu_map__cpu(evlist->all_cpus, cpu_idx);460	struct perf_evsel *evsel;461	int revent;462 463	perf_evlist__for_each_entry(evlist, evsel) {464		bool overwrite = evsel->attr.write_backward;465		enum fdarray_flags flgs;466		struct perf_mmap *map;467		int *output, fd, cpu;468 469		if (evsel->system_wide && thread)470			continue;471 472		cpu = perf_cpu_map__idx(evsel->cpus, evlist_cpu);473		if (cpu == -1)474			continue;475 476		map = ops->get(evlist, overwrite, idx);477		if (map == NULL)478			return -ENOMEM;479 480		if (overwrite) {481			mp->prot = PROT_READ;482			output   = _output_overwrite;483		} else {484			mp->prot = PROT_READ | PROT_WRITE;485			output   = _output;486		}487 488		fd = FD(evsel, cpu, thread);489 490		if (*output == -1) {491			*output = fd;492 493			/*494			 * The last one will be done at perf_mmap__consume(), so that we495			 * make sure we don't prevent tools from consuming every last event in496			 * the ring buffer.497			 *498			 * I.e. we can get the POLLHUP meaning that the fd doesn't exist499			 * anymore, but the last events for it are still in the ring buffer,500			 * waiting to be consumed.501			 *502			 * Tools can chose to ignore this at their own discretion, but the503			 * evlist layer can't just drop it when filtering events in504			 * perf_evlist__filter_pollfd().505			 */506			refcount_set(&map->refcnt, 2);507 508			if (ops->idx)509				ops->idx(evlist, evsel, mp, idx);510 511			/* Debug message used by test scripts */512			pr_debug("idx %d: mmapping fd %d\n", idx, *output);513			if (ops->mmap(map, mp, *output, evlist_cpu) < 0)514				return -1;515 516			*nr_mmaps += 1;517 518			if (!idx)519				perf_evlist__set_mmap_first(evlist, map, overwrite);520		} else {521			/* Debug message used by test scripts */522			pr_debug("idx %d: set output fd %d -> %d\n", idx, fd, *output);523			if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0)524				return -1;525 526			perf_mmap__get(map);527		}528 529		revent = !overwrite ? POLLIN : 0;530 531		flgs = evsel->system_wide ? fdarray_flag__nonfilterable : fdarray_flag__default;532		if (perf_evlist__add_pollfd(evlist, fd, map, revent, flgs) < 0) {533			perf_mmap__put(map);534			return -1;535		}536 537		if (evsel->attr.read_format & PERF_FORMAT_ID) {538			if (perf_evlist__id_add_fd(evlist, evsel, cpu, thread,539						   fd) < 0)540				return -1;541			perf_evsel__set_sid_idx(evsel, idx, cpu, thread);542		}543	}544 545	return 0;546}547 548static int549mmap_per_thread(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,550		struct perf_mmap_param *mp)551{552	int nr_threads = perf_thread_map__nr(evlist->threads);553	int nr_cpus    = perf_cpu_map__nr(evlist->all_cpus);554	int cpu, thread, idx = 0;555	int nr_mmaps = 0;556 557	pr_debug("%s: nr cpu values (may include -1) %d nr threads %d\n",558		 __func__, nr_cpus, nr_threads);559 560	/* per-thread mmaps */561	for (thread = 0; thread < nr_threads; thread++, idx++) {562		int output = -1;563		int output_overwrite = -1;564 565		if (mmap_per_evsel(evlist, ops, idx, mp, 0, thread, &output,566				   &output_overwrite, &nr_mmaps))567			goto out_unmap;568	}569 570	/* system-wide mmaps i.e. per-cpu */571	for (cpu = 1; cpu < nr_cpus; cpu++, idx++) {572		int output = -1;573		int output_overwrite = -1;574 575		if (mmap_per_evsel(evlist, ops, idx, mp, cpu, 0, &output,576				   &output_overwrite, &nr_mmaps))577			goto out_unmap;578	}579 580	if (nr_mmaps != evlist->nr_mmaps)581		pr_err("Miscounted nr_mmaps %d vs %d\n", nr_mmaps, evlist->nr_mmaps);582 583	return 0;584 585out_unmap:586	perf_evlist__munmap(evlist);587	return -1;588}589 590static int591mmap_per_cpu(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,592	     struct perf_mmap_param *mp)593{594	int nr_threads = perf_thread_map__nr(evlist->threads);595	int nr_cpus    = perf_cpu_map__nr(evlist->all_cpus);596	int nr_mmaps = 0;597	int cpu, thread;598 599	pr_debug("%s: nr cpu values %d nr threads %d\n", __func__, nr_cpus, nr_threads);600 601	for (cpu = 0; cpu < nr_cpus; cpu++) {602		int output = -1;603		int output_overwrite = -1;604 605		for (thread = 0; thread < nr_threads; thread++) {606			if (mmap_per_evsel(evlist, ops, cpu, mp, cpu,607					   thread, &output, &output_overwrite, &nr_mmaps))608				goto out_unmap;609		}610	}611 612	if (nr_mmaps != evlist->nr_mmaps)613		pr_err("Miscounted nr_mmaps %d vs %d\n", nr_mmaps, evlist->nr_mmaps);614 615	return 0;616 617out_unmap:618	perf_evlist__munmap(evlist);619	return -1;620}621 622static int perf_evlist__nr_mmaps(struct perf_evlist *evlist)623{624	int nr_mmaps;625 626	/* One for each CPU */627	nr_mmaps = perf_cpu_map__nr(evlist->all_cpus);628	if (perf_cpu_map__has_any_cpu_or_is_empty(evlist->all_cpus)) {629		/* Plus one for each thread */630		nr_mmaps += perf_thread_map__nr(evlist->threads);631		/* Minus the per-thread CPU (-1) */632		nr_mmaps -= 1;633	}634 635	return nr_mmaps;636}637 638int perf_evlist__mmap_ops(struct perf_evlist *evlist,639			  struct perf_evlist_mmap_ops *ops,640			  struct perf_mmap_param *mp)641{642	const struct perf_cpu_map *cpus = evlist->all_cpus;643	struct perf_evsel *evsel;644 645	if (!ops || !ops->get || !ops->mmap)646		return -EINVAL;647 648	mp->mask = evlist->mmap_len - page_size - 1;649 650	evlist->nr_mmaps = perf_evlist__nr_mmaps(evlist);651 652	perf_evlist__for_each_entry(evlist, evsel) {653		if ((evsel->attr.read_format & PERF_FORMAT_ID) &&654		    evsel->sample_id == NULL &&655		    perf_evsel__alloc_id(evsel, evsel->fd->max_x, evsel->fd->max_y) < 0)656			return -ENOMEM;657	}658 659	if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0)660		return -ENOMEM;661 662	if (perf_cpu_map__has_any_cpu_or_is_empty(cpus))663		return mmap_per_thread(evlist, ops, mp);664 665	return mmap_per_cpu(evlist, ops, mp);666}667 668int perf_evlist__mmap(struct perf_evlist *evlist, int pages)669{670	struct perf_mmap_param mp;671	struct perf_evlist_mmap_ops ops = {672		.get  = perf_evlist__mmap_cb_get,673		.mmap = perf_evlist__mmap_cb_mmap,674	};675 676	evlist->mmap_len = (pages + 1) * page_size;677 678	return perf_evlist__mmap_ops(evlist, &ops, &mp);679}680 681void perf_evlist__munmap(struct perf_evlist *evlist)682{683	int i;684 685	if (evlist->mmap) {686		for (i = 0; i < evlist->nr_mmaps; i++)687			perf_mmap__munmap(&evlist->mmap[i]);688	}689 690	if (evlist->mmap_ovw) {691		for (i = 0; i < evlist->nr_mmaps; i++)692			perf_mmap__munmap(&evlist->mmap_ovw[i]);693	}694 695	zfree(&evlist->mmap);696	zfree(&evlist->mmap_ovw);697}698 699struct perf_mmap*700perf_evlist__next_mmap(struct perf_evlist *evlist, struct perf_mmap *map,701		       bool overwrite)702{703	if (map)704		return map->next;705 706	return overwrite ? evlist->mmap_ovw_first : evlist->mmap_first;707}708 709void __perf_evlist__set_leader(struct list_head *list, struct perf_evsel *leader)710{711	struct perf_evsel *evsel;712	int n = 0;713 714	__perf_evlist__for_each_entry(list, evsel) {715		evsel->leader = leader;716		n++;717	}718	leader->nr_members = n;719}720 721void perf_evlist__set_leader(struct perf_evlist *evlist)722{723	if (evlist->nr_entries) {724		struct perf_evsel *first = list_entry(evlist->entries.next,725						struct perf_evsel, node);726 727		__perf_evlist__set_leader(&evlist->entries, first);728	}729}730 731int perf_evlist__nr_groups(struct perf_evlist *evlist)732{733	struct perf_evsel *evsel;734	int nr_groups = 0;735 736	perf_evlist__for_each_evsel(evlist, evsel) {737		/*738		 * evsels by default have a nr_members of 1, and they are their739		 * own leader. If the nr_members is >1 then this is an740		 * indication of a group.741		 */742		if (evsel->leader == evsel && evsel->nr_members > 1)743			nr_groups++;744	}745	return nr_groups;746}747 748void perf_evlist__go_system_wide(struct perf_evlist *evlist, struct perf_evsel *evsel)749{750	if (!evsel->system_wide) {751		evsel->system_wide = true;752		if (evlist->needs_map_propagation)753			__perf_evlist__propagate_maps(evlist, evsel);754	}755}756