Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 1087 insertions, 0 deletions

diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
new file mode 100644
index 000000000..c0e2b9d5f
--- /dev/null
+++ b/tools/perf/util/env.c
@@ -0,0 +1,1087 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "cpumap.h"
+#include "dwarf-regs.h"
+#include "debug.h"
+#include "env.h"
+#include "util/header.h"
+#include "util/rwsem.h"
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/rbtree.h>
+#include <linux/string.h>
+#include <linux/zalloc.h>
+#include "cgroup.h"
+#include <errno.h>
+#include <sys/utsname.h>
+#include <stdlib.h>
+#include <string.h>
+#include "pmu.h"
+#include "pmus.h"
+#include "strbuf.h"
+#include "trace/beauty/beauty.h"
+
+#ifdef HAVE_LIBBPF_SUPPORT
+#include "bpf-event.h"
+#include "bpf-utils.h"
+#include <bpf/libbpf.h>
+
+bool perf_env__insert_bpf_prog_info(struct perf_env *env,
+				    struct bpf_prog_info_node *info_node)
+{
+	bool ret;
+
+	down_write(&env->bpf_progs.lock);
+	ret = __perf_env__insert_bpf_prog_info(env, info_node);
+	up_write(&env->bpf_progs.lock);
+
+	return ret;
+}
+
+bool __perf_env__insert_bpf_prog_info(struct perf_env *env, struct bpf_prog_info_node *info_node)
+{
+	__u32 prog_id = info_node->info_linear->info.id;
+	struct bpf_prog_info_node *node;
+	struct rb_node *parent = NULL;
+	struct rb_node **p;
+
+	p = &env->bpf_progs.infos.rb_node;
+
+	while (*p != NULL) {
+		parent = *p;
+		node = rb_entry(parent, struct bpf_prog_info_node, rb_node);
+		if (prog_id < node->info_linear->info.id) {
+			p = &(*p)->rb_left;
+		} else if (prog_id > node->info_linear->info.id) {
+			p = &(*p)->rb_right;
+		} else {
+			pr_debug("duplicated bpf prog info %u\n", prog_id);
+			return false;
+		}
+	}
+
+	rb_link_node(&info_node->rb_node, parent, p);
+	rb_insert_color(&info_node->rb_node, &env->bpf_progs.infos);
+	env->bpf_progs.infos_cnt++;
+	return true;
+}
+
+struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
+							__u32 prog_id)
+{
+	struct bpf_prog_info_node *node = NULL;
+	struct rb_node *n;
+
+	down_read(&env->bpf_progs.lock);
+	n = env->bpf_progs.infos.rb_node;
+
+	while (n) {
+		node = rb_entry(n, struct bpf_prog_info_node, rb_node);
+		if (prog_id < node->info_linear->info.id)
+			n = n->rb_left;
+		else if (prog_id > node->info_linear->info.id)
+			n = n->rb_right;
+		else
+			goto out;
+	}
+	node = NULL;
+
+out:
+	up_read(&env->bpf_progs.lock);
+	return node;
+}
+
+void perf_env__iterate_bpf_prog_info(struct perf_env *env,
+				     void (*cb)(struct bpf_prog_info_node *node,
+						void *data),
+				     void *data)
+{
+	struct rb_node *first;
+
+	down_read(&env->bpf_progs.lock);
+	first = rb_first(&env->bpf_progs.infos);
+	for (struct rb_node *node = first; node != NULL; node = rb_next(node))
+		(*cb)(rb_entry(node, struct bpf_prog_info_node, rb_node), data);
+	up_read(&env->bpf_progs.lock);
+}
+
+bool perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node)
+{
+	bool ret;
+
+	down_write(&env->bpf_progs.lock);
+	ret = __perf_env__insert_btf(env, btf_node);
+	up_write(&env->bpf_progs.lock);
+	return ret;
+}
+
+bool __perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node)
+{
+	struct rb_node *parent = NULL;
+	__u32 btf_id = btf_node->id;
+	struct btf_node *node;
+	struct rb_node **p;
+
+	p = &env->bpf_progs.btfs.rb_node;
+
+	while (*p != NULL) {
+		parent = *p;
+		node = rb_entry(parent, struct btf_node, rb_node);
+		if (btf_id < node->id) {
+			p = &(*p)->rb_left;
+		} else if (btf_id > node->id) {
+			p = &(*p)->rb_right;
+		} else {
+			pr_debug("duplicated btf %u\n", btf_id);
+			return false;
+		}
+	}
+
+	rb_link_node(&btf_node->rb_node, parent, p);
+	rb_insert_color(&btf_node->rb_node, &env->bpf_progs.btfs);
+	env->bpf_progs.btfs_cnt++;
+	return true;
+}
+
+struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id)
+{
+	struct btf_node *res;
+
+	down_read(&env->bpf_progs.lock);
+	res = __perf_env__find_btf(env, btf_id);
+	up_read(&env->bpf_progs.lock);
+	return res;
+}
+
+struct btf_node *__perf_env__find_btf(struct perf_env *env, __u32 btf_id)
+{
+	struct btf_node *node = NULL;
+	struct rb_node *n;
+
+	n = env->bpf_progs.btfs.rb_node;
+
+	while (n) {
+		node = rb_entry(n, struct btf_node, rb_node);
+		if (btf_id < node->id)
+			n = n->rb_left;
+		else if (btf_id > node->id)
+			n = n->rb_right;
+		else
+			return node;
+	}
+	return NULL;
+}
+
+/* purge data in bpf_progs.infos tree */
+static void perf_env__purge_bpf(struct perf_env *env)
+{
+	struct rb_root *root;
+	struct rb_node *next;
+
+	down_write(&env->bpf_progs.lock);
+
+	root = &env->bpf_progs.infos;
+	next = rb_first(root);
+
+	while (next) {
+		struct bpf_prog_info_node *node;
+
+		node = rb_entry(next, struct bpf_prog_info_node, rb_node);
+		next = rb_next(&node->rb_node);
+		rb_erase(&node->rb_node, root);
+		zfree(&node->info_linear);
+		bpf_metadata_free(node->metadata);
+		free(node);
+	}
+
+	env->bpf_progs.infos_cnt = 0;
+
+	root = &env->bpf_progs.btfs;
+	next = rb_first(root);
+
+	while (next) {
+		struct btf_node *node;
+
+		node = rb_entry(next, struct btf_node, rb_node);
+		next = rb_next(&node->rb_node);
+		rb_erase(&node->rb_node, root);
+		free(node);
+	}
+
+	env->bpf_progs.btfs_cnt = 0;
+
+	up_write(&env->bpf_progs.lock);
+}
+#else // HAVE_LIBBPF_SUPPORT
+static void perf_env__purge_bpf(struct perf_env *env __maybe_unused)
+{
+}
+#endif // HAVE_LIBBPF_SUPPORT
+
+void free_cpu_domain_info(struct cpu_domain_map **cd_map, u32 schedstat_version, u32 nr)
+{
+	if (!cd_map)
+		return;
+
+	for (u32 i = 0; i < nr; i++) {
+		if (!cd_map[i])
+			continue;
+
+		for (u32 j = 0; j < cd_map[i]->nr_domains; j++) {
+			struct domain_info *d_info = cd_map[i]->domains[j];
+
+			if (!d_info)
+				continue;
+
+			if (schedstat_version >= 17)
+				zfree(&d_info->dname);
+
+			zfree(&d_info->cpumask);
+			zfree(&d_info->cpulist);
+			zfree(&d_info);
+		}
+		zfree(&cd_map[i]->domains);
+		zfree(&cd_map[i]);
+	}
+	zfree(&cd_map);
+}
+
+void perf_env__exit(struct perf_env *env)
+{
+	int i, j;
+
+	mutex_destroy(&env->lock);
+
+	perf_env__purge_bpf(env);
+	perf_env__purge_cgroups(env);
+	zfree(&env->hostname);
+	zfree(&env->os_release);
+	zfree(&env->version);
+	zfree(&env->arch);
+	zfree(&env->cpu_desc);
+	zfree(&env->cpuid);
+	zfree(&env->cmdline);
+	zfree(&env->cmdline_argv);
+	zfree(&env->sibling_dies);
+	zfree(&env->sibling_cores);
+	zfree(&env->sibling_threads);
+	zfree(&env->pmu_mappings);
+	zfree(&env->cpu);
+	for (i = 0; i < env->nr_cpu_pmu_caps; i++)
+		zfree(&env->cpu_pmu_caps[i]);
+	zfree(&env->cpu_pmu_caps);
+	zfree(&env->numa_map);
+
+	for (i = 0; i < env->nr_numa_nodes; i++)
+		perf_cpu_map__put(env->numa_nodes[i].map);
+	zfree(&env->numa_nodes);
+
+	for (i = 0; i < env->caches_cnt; i++)
+		cpu_cache_level__free(&env->caches[i]);
+	zfree(&env->caches);
+
+	for (i = 0; i < env->nr_memory_nodes; i++)
+		zfree(&env->memory_nodes[i].set);
+	zfree(&env->memory_nodes);
+
+	for (i = 0; i < env->nr_hybrid_nodes; i++) {
+		zfree(&env->hybrid_nodes[i].pmu_name);
+		zfree(&env->hybrid_nodes[i].cpus);
+	}
+	zfree(&env->hybrid_nodes);
+
+	for (i = 0; i < env->nr_pmus_with_caps; i++) {
+		for (j = 0; j < env->pmu_caps[i].nr_caps; j++)
+			zfree(&env->pmu_caps[i].caps[j]);
+		zfree(&env->pmu_caps[i].caps);
+		zfree(&env->pmu_caps[i].pmu_name);
+	}
+	zfree(&env->pmu_caps);
+	free_cpu_domain_info(env->cpu_domain, env->schedstat_version, env->nr_cpus_avail);
+}
+
+void perf_env__init(struct perf_env *env)
+{
+	memset(env, 0, sizeof(*env));
+#ifdef HAVE_LIBBPF_SUPPORT
+	env->bpf_progs.infos = RB_ROOT;
+	env->bpf_progs.btfs = RB_ROOT;
+	init_rwsem(&env->bpf_progs.lock);
+#endif
+	env->kernel_is_64_bit = -1;
+	mutex_init(&env->lock);
+}
+
+static void perf_env__init_kernel_mode(struct perf_env *env)
+{
+	const char *arch = env->arch;
+
+	if (!arch) {
+		static struct utsname uts = { .machine[0] = '\0', };
+
+		if (uts.machine[0] == '\0')
+			uname(&uts);
+		if (uts.machine[0] != '\0')
+			arch = uts.machine;
+	}
+
+	if (arch) {
+		if (strstr(arch, "64") || strstr(arch, "s390x"))
+			env->kernel_is_64_bit = 1;
+		else
+			env->kernel_is_64_bit = 0;
+		return;
+	}
+
+	/* Fallback if completely unresolvable (assume host-bitness) */
+	env->kernel_is_64_bit = (sizeof(void *) == 8) ? 1 : 0;
+}
+
+int perf_env__kernel_is_64_bit(struct perf_env *env)
+{
+	if (env->kernel_is_64_bit == -1)
+		perf_env__init_kernel_mode(env);
+
+	return env->kernel_is_64_bit;
+}
+
+bool perf_arch_is_big_endian(const char *arch)
+{
+	if (!arch)
+		return __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__;
+
+	if (str_ends_with(arch, "_be") || !strcmp(arch, "sparc") || !strcmp(arch, "sparc64") ||
+	    !strcmp(arch, "s390") || !strcmp(arch, "s390x") || !strcmp(arch, "powerpc") ||
+	    !strcmp(arch, "ppc") || !strcmp(arch, "ppc64") ||
+	    !strcmp(arch, "mips") || !strcmp(arch, "mips64") || !strcmp(arch, "parisc") ||
+	    !strcmp(arch, "parisc64") || !strcmp(arch, "m68k") ||
+	    !strcmp(arch, "armeb") || !strcmp(arch, "mipseb") || !strcmp(arch, "mips64eb"))
+		return true;
+
+	return false;
+}
+
+const char *perf_env__os_release(struct perf_env *env)
+{
+	struct utsname uts;
+	int ret;
+	const char *release;
+
+	if (!env)
+		return perf_version_string;
+
+	mutex_lock(&env->lock);
+	if (env->os_release) {
+		release = env->os_release;
+		goto out;
+	}
+
+	/*
+	 * If env->arch is set, this is an offline target environment.
+	 * If the os_release is not populated in the file, we do not want
+	 * to poison it with the host's release which would break guest checks.
+	 */
+	if (env->arch) {
+		release = NULL;
+		goto out;
+	}
+
+	/*
+	 * The os_release is being accessed but wasn't initialized from a data
+	 * file, assume this is 'live' mode and use the release from uname. If
+	 * uname or strdup fails then use the current perf tool version.
+	 */
+	ret = uname(&uts);
+	env->os_release = strdup(ret < 0 ? perf_version_string : uts.release);
+	release = env->os_release ?: perf_version_string;
+out:
+	mutex_unlock(&env->lock);
+	return release;
+}
+
+int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[])
+{
+	int i;
+
+	/* do not include NULL termination */
+	env->cmdline_argv = calloc(argc, sizeof(char *));
+	if (env->cmdline_argv == NULL)
+		goto out_enomem;
+
+	/*
+	 * Must copy argv contents because it gets moved around during option
+	 * parsing:
+	 */
+	for (i = 0; i < argc ; i++) {
+		env->cmdline_argv[i] = argv[i];
+		if (env->cmdline_argv[i] == NULL)
+			goto out_free;
+	}
+
+	env->nr_cmdline = argc;
+
+	return 0;
+out_free:
+	zfree(&env->cmdline_argv);
+out_enomem:
+	return -ENOMEM;
+}
+
+int perf_env__read_cpu_topology_map(struct perf_env *env)
+{
+	int idx, nr_cpus;
+
+	if (env->cpu != NULL)
+		return 0;
+
+	if (env->nr_cpus_avail == 0)
+		env->nr_cpus_avail = cpu__max_present_cpu().cpu;
+
+	nr_cpus = env->nr_cpus_avail;
+	if (nr_cpus == -1)
+		return -EINVAL;
+
+	env->cpu = calloc(nr_cpus, sizeof(env->cpu[0]));
+	if (env->cpu == NULL)
+		return -ENOMEM;
+
+	for (idx = 0; idx < nr_cpus; ++idx) {
+		struct perf_cpu cpu = { .cpu = idx };
+		int core_id   = cpu__get_core_id(cpu);
+		int socket_id = cpu__get_socket_id(cpu);
+		int die_id    = cpu__get_die_id(cpu);
+
+		env->cpu[idx].core_id	= core_id >= 0 ? core_id : -1;
+		env->cpu[idx].socket_id	= socket_id >= 0 ? socket_id : -1;
+		env->cpu[idx].die_id	= die_id >= 0 ? die_id : -1;
+	}
+
+	env->nr_cpus_avail = nr_cpus;
+	return 0;
+}
+
+int perf_env__read_pmu_mappings(struct perf_env *env)
+{
+	struct perf_pmu *pmu = NULL;
+	u32 pmu_num = 0;
+	struct strbuf sb;
+
+	while ((pmu = perf_pmus__scan(pmu)))
+		pmu_num++;
+
+	if (!pmu_num) {
+		pr_debug("pmu mappings not available\n");
+		return -ENOENT;
+	}
+	env->nr_pmu_mappings = pmu_num;
+
+	if (strbuf_init(&sb, 128 * pmu_num) < 0)
+		return -ENOMEM;
+
+	while ((pmu = perf_pmus__scan(pmu))) {
+		if (strbuf_addf(&sb, "%u:%s", pmu->type, pmu->name) < 0)
+			goto error;
+		/* include a NULL character at the end */
+		if (strbuf_add(&sb, "", 1) < 0)
+			goto error;
+	}
+
+	env->pmu_mappings = strbuf_detach(&sb, NULL);
+
+	return 0;
+
+error:
+	strbuf_release(&sb);
+	return -1;
+}
+
+int perf_env__read_cpuid(struct perf_env *env)
+{
+	char cpuid[128];
+	struct perf_cpu cpu = {-1};
+	int err = get_cpuid(cpuid, sizeof(cpuid), cpu);
+
+	if (err)
+		return err;
+
+	free(env->cpuid);
+	env->cpuid = strdup(cpuid);
+	if (env->cpuid == NULL)
+		return ENOMEM;
+	return 0;
+}
+
+static int perf_env__read_nr_cpus_avail(struct perf_env *env)
+{
+	if (env->nr_cpus_avail == 0)
+		env->nr_cpus_avail = cpu__max_present_cpu().cpu;
+
+	return env->nr_cpus_avail ? 0 : -ENOENT;
+}
+
+static int __perf_env__read_core_pmu_caps(const struct perf_pmu *pmu,
+					  int *nr_caps, char ***caps,
+					  unsigned int *max_branches,
+					  unsigned int *br_cntr_nr,
+					  unsigned int *br_cntr_width)
+{
+	struct perf_pmu_caps *pcaps = NULL;
+	char *ptr, **tmp;
+	int ret = 0;
+
+	*nr_caps = 0;
+	*caps = NULL;
+
+	if (!pmu->nr_caps)
+		return 0;
+
+	*caps = calloc(pmu->nr_caps, sizeof(char *));
+	if (!*caps)
+		return -ENOMEM;
+
+	tmp = *caps;
+	list_for_each_entry(pcaps, &pmu->caps, list) {
+		if (asprintf(&ptr, "%s=%s", pcaps->name, pcaps->value) < 0) {
+			ret = -ENOMEM;
+			goto error;
+		}
+
+		*tmp++ = ptr;
+
+		if (!strcmp(pcaps->name, "branches"))
+			*max_branches = atoi(pcaps->value);
+		else if (!strcmp(pcaps->name, "branch_counter_nr"))
+			*br_cntr_nr = atoi(pcaps->value);
+		else if (!strcmp(pcaps->name, "branch_counter_width"))
+			*br_cntr_width = atoi(pcaps->value);
+	}
+	*nr_caps = pmu->nr_caps;
+	return 0;
+error:
+	while (tmp-- != *caps)
+		zfree(tmp);
+	zfree(caps);
+	*nr_caps = 0;
+	return ret;
+}
+
+int perf_env__read_core_pmu_caps(struct perf_env *env)
+{
+	struct pmu_caps *pmu_caps;
+	struct perf_pmu *pmu = NULL;
+	int nr_pmu, i = 0, j;
+	int ret;
+
+	nr_pmu = perf_pmus__num_core_pmus();
+
+	if (!nr_pmu)
+		return -ENODEV;
+
+	if (nr_pmu == 1) {
+		pmu = perf_pmus__find_core_pmu();
+		if (!pmu)
+			return -ENODEV;
+		ret = perf_pmu__caps_parse(pmu);
+		if (ret < 0)
+			return ret;
+		return __perf_env__read_core_pmu_caps(pmu, &env->nr_cpu_pmu_caps,
+						      &env->cpu_pmu_caps,
+						      &env->max_branches,
+						      &env->br_cntr_nr,
+						      &env->br_cntr_width);
+	}
+
+	pmu_caps = calloc(nr_pmu, sizeof(*pmu_caps));
+	if (!pmu_caps)
+		return -ENOMEM;
+
+	while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
+		if (perf_pmu__caps_parse(pmu) <= 0)
+			continue;
+		ret = __perf_env__read_core_pmu_caps(pmu, &pmu_caps[i].nr_caps,
+						     &pmu_caps[i].caps,
+						     &pmu_caps[i].max_branches,
+						     &pmu_caps[i].br_cntr_nr,
+						     &pmu_caps[i].br_cntr_width);
+		if (ret)
+			goto error;
+
+		pmu_caps[i].pmu_name = strdup(pmu->name);
+		if (!pmu_caps[i].pmu_name) {
+			ret = -ENOMEM;
+			goto error;
+		}
+		i++;
+	}
+
+	env->nr_pmus_with_caps = nr_pmu;
+	env->pmu_caps = pmu_caps;
+
+	return 0;
+error:
+	for (i = 0; i < nr_pmu; i++) {
+		for (j = 0; j < pmu_caps[i].nr_caps; j++)
+			zfree(&pmu_caps[i].caps[j]);
+		zfree(&pmu_caps[i].caps);
+		zfree(&pmu_caps[i].pmu_name);
+	}
+	zfree(&pmu_caps);
+	return ret;
+}
+
+int perf_env__nr_cpus_avail(struct perf_env *env)
+{
+	return env && !perf_env__read_nr_cpus_avail(env) ? env->nr_cpus_avail : 0;
+}
+
+void cpu_cache_level__free(struct cpu_cache_level *cache)
+{
+	zfree(&cache->type);
+	zfree(&cache->map);
+	zfree(&cache->size);
+}
+
+struct arch_to_e_machine {
+	const char *prefix;
+	uint16_t e_machine;
+};
+
+/*
+ * A mapping from an arch prefix string to an ELF machine that can be used in a
+ * bsearch. Some arch prefixes are shared an need additional processing as
+ * marked next to the architecture. The prefixes handle both perf's architecture
+ * naming and those from uname.
+ */
+static const struct arch_to_e_machine prefix_to_e_machine[] = {
+	{"aarch64", EM_AARCH64},
+	{"alpha", EM_ALPHA},
+	{"arc", EM_ARC},
+	{"arm", EM_ARM}, /* Check also for EM_AARCH64. */
+	{"avr", EM_AVR},  /* Check also for EM_AVR32. */
+	{"bfin", EM_BLACKFIN},
+	{"blackfin", EM_BLACKFIN},
+	{"cris", EM_CRIS},
+	{"csky", EM_CSKY},
+	{"hppa", EM_PARISC},
+	{"i386", EM_386},
+	{"i486", EM_386},
+	{"i586", EM_386},
+	{"i686", EM_386},
+	{"loongarch", EM_LOONGARCH},
+	{"m32r", EM_M32R},
+	{"m68k", EM_68K},
+	{"microblaze", EM_MICROBLAZE},
+	{"mips", EM_MIPS},
+	{"msp430", EM_MSP430},
+	{"parisc", EM_PARISC},
+	{"powerpc", EM_PPC}, /* Check also for EM_PPC64. */
+	{"ppc", EM_PPC}, /* Check also for EM_PPC64. */
+	{"riscv", EM_RISCV},
+	{"s390", EM_S390},
+	{"sa110", EM_ARM},
+	{"sh", EM_SH},
+	{"sparc", EM_SPARC}, /* Check also for EM_SPARCV9. */
+	{"sun4u", EM_SPARC},
+	{"x86", EM_X86_64}, /* Check also for EM_386. */
+	{"xtensa", EM_XTENSA},
+};
+
+static int compare_prefix(const void *key, const void *element)
+{
+	const char *search_key = key;
+	const struct arch_to_e_machine *map_element = element;
+	size_t prefix_len = strlen(map_element->prefix);
+
+	return strncmp(search_key, map_element->prefix, prefix_len);
+}
+
+static uint16_t perf_arch_to_e_machine(const char *perf_arch, int is_64_bit)
+{
+	/* Binary search for a matching prefix. */
+	const struct arch_to_e_machine *result;
+
+	if (!perf_arch)
+		return EM_HOST;
+
+	result = bsearch(perf_arch,
+			 prefix_to_e_machine, ARRAY_SIZE(prefix_to_e_machine),
+			 sizeof(prefix_to_e_machine[0]),
+			 compare_prefix);
+
+	if (!result) {
+		pr_debug("Unknown perf arch for ELF machine mapping: %s\n", perf_arch);
+		return EM_NONE;
+	}
+
+	/*
+	 * Handle conflicting prefixes. If the is_64_bit is unknown (-1) then
+	 * assume 64-bit. We can't use perf_env__kernel_is_64_bit as that
+	 * depends on the arch string.
+	 */
+	switch (result->e_machine) {
+	case EM_ARM:
+		return !strcmp(perf_arch, "arm64") || !strcmp(perf_arch, "aarch64")
+			? EM_AARCH64 : EM_ARM;
+	case EM_AVR:
+		return !strcmp(perf_arch, "avr32") ? EM_AVR32 : EM_AVR;
+	case EM_PPC:
+		if (is_64_bit == 1)
+			return EM_PPC64;
+		if (is_64_bit == 0)
+			return EM_PPC;
+		return strstarts(perf_arch, "ppc64") ? EM_PPC64 : EM_PPC;
+	case EM_SPARC:
+		if (is_64_bit == 1)
+			return EM_SPARCV9;
+		if (is_64_bit == 0)
+			return EM_SPARC;
+		return !strcmp(perf_arch, "sparc64") || !strcmp(perf_arch, "sun4u")
+			? EM_SPARCV9 : EM_SPARC;
+	case EM_X86_64:
+		if (is_64_bit == 1)
+			return EM_X86_64;
+		if (is_64_bit == 0)
+			return EM_386;
+		return !strcmp(perf_arch, "x86_64") || !strcmp(perf_arch, "x86")
+			? EM_X86_64 : EM_386;
+	default:
+		return result->e_machine;
+	}
+}
+
+static const char *e_machine_to_perf_arch(uint16_t e_machine)
+{
+	/*
+	 * Table for if either the perf arch string differs from uname or there
+	 * are >1 ELF machine with the prefix.
+	 */
+	static const struct arch_to_e_machine extras[] = {
+		{"arm64", EM_AARCH64},
+		{"avr32", EM_AVR32},
+		{"powerpc", EM_PPC},
+		{"powerpc", EM_PPC64},
+		{"sparc", EM_SPARCV9},
+		{"x86", EM_386},
+		{"x86", EM_X86_64},
+		{"none", EM_NONE},
+	};
+
+	for (size_t i = 0; i < ARRAY_SIZE(extras); i++) {
+		if (extras[i].e_machine == e_machine)
+			return extras[i].prefix;
+	}
+
+	for (size_t i = 0; i < ARRAY_SIZE(prefix_to_e_machine); i++) {
+		if (prefix_to_e_machine[i].e_machine == e_machine)
+			return prefix_to_e_machine[i].prefix;
+
+	}
+	return "unknown";
+}
+
+uint16_t perf_env__e_machine_nocache(struct perf_env *env, uint32_t *e_flags)
+{
+	uint16_t e_machine = EM_NONE;
+	const char *arch = NULL;
+	int is_64_bit = -1;
+
+	if (e_flags)
+		*e_flags = 0;
+
+	if (env) {
+		arch = env->arch;
+		is_64_bit = env->kernel_is_64_bit;
+	}
+
+	if (!arch) {
+		static struct utsname uts = { .machine[0] = '\0', };
+
+		if (uts.machine[0] == '\0')
+			uname(&uts);
+		if (uts.machine[0] != '\0')
+			arch = uts.machine;
+	}
+
+	e_machine = perf_arch_to_e_machine(arch, is_64_bit);
+
+	if (e_flags)
+		*e_flags = (e_machine == EM_HOST) ? EF_HOST : 0;
+
+	return e_machine;
+}
+
+uint16_t perf_env__e_machine(struct perf_env *env, uint32_t *e_flags)
+{
+	uint16_t e_machine;
+	uint32_t local_e_flags = 0;
+
+	if (env && env->e_machine != EM_NONE) {
+		if (e_flags)
+			*e_flags = env->e_flags;
+
+		return env->e_machine;
+	}
+	e_machine = perf_env__e_machine_nocache(env, &local_e_flags);
+	/*
+	 * Only cache the e_machine in perf_env if env->arch is not NULL.
+	 * If env->arch is NULL, the e_machine is just a fallback to EM_HOST.
+	 * Caching it permanently would prevent dynamic, more accurate
+	 * thread-based session e_machine scanning later in
+	 * perf_session__e_machine().
+	 */
+	if (env && env->arch) {
+		env->e_machine = e_machine;
+		env->e_flags = local_e_flags;
+	}
+	if (e_flags)
+		*e_flags = local_e_flags;
+
+	return e_machine;
+}
+
+const char *perf_env__arch(struct perf_env *env)
+{
+	uint16_t e_machine;
+	const char *arch;
+
+	if (!env) {
+		static struct utsname uts = { .machine[0] = '\0', };
+		uint16_t host_e_machine;
+
+		if (uts.machine[0] == '\0')
+			uname(&uts);
+		if (uts.machine[0] != '\0') {
+			host_e_machine = perf_arch_to_e_machine(uts.machine, -1);
+			return e_machine_to_perf_arch(host_e_machine);
+		}
+		return e_machine_to_perf_arch(EM_HOST);
+	}
+
+	/*
+	 * Lazily compute/allocate arch. The e_machine may have been
+	 * read from a data file and so may not be EM_HOST.
+	 */
+	e_machine = perf_env__e_machine(env, /*e_flags=*/NULL);
+	arch = e_machine_to_perf_arch(e_machine);
+
+	if (e_machine == EM_RISCV && perf_env__kernel_is_64_bit(env) == 1)
+		arch = "riscv64";
+	else if (e_machine == EM_MIPS && perf_env__kernel_is_64_bit(env) == 1)
+		arch = "mips64";
+	else if (e_machine == EM_PARISC && perf_env__kernel_is_64_bit(env) == 1)
+		arch = "parisc64";
+
+	return arch;
+}
+
+const char *arch_syscalls__strerrno(uint16_t e_machine, int err);
+
+const char *perf_env__arch_strerrno(uint16_t e_machine, int err)
+{
+	return arch_syscalls__strerrno(e_machine, err);
+}
+
+const char *perf_env__cpuid(struct perf_env *env)
+{
+	int status;
+
+	if (!env->cpuid) { /* Assume local operation */
+		status = perf_env__read_cpuid(env);
+		if (status)
+			return NULL;
+	}
+
+	return env->cpuid;
+}
+
+int perf_env__nr_pmu_mappings(struct perf_env *env)
+{
+	int status;
+
+	if (!env->nr_pmu_mappings) { /* Assume local operation */
+		status = perf_env__read_pmu_mappings(env);
+		if (status)
+			return 0;
+	}
+
+	return env->nr_pmu_mappings;
+}
+
+const char *perf_env__pmu_mappings(struct perf_env *env)
+{
+	int status;
+
+	if (!env->pmu_mappings) { /* Assume local operation */
+		status = perf_env__read_pmu_mappings(env);
+		if (status)
+			return NULL;
+	}
+
+	return env->pmu_mappings;
+}
+
+int perf_env__numa_node(struct perf_env *env, struct perf_cpu cpu)
+{
+	if (!env->nr_numa_map) {
+		struct numa_node *nn;
+		int i, nr = 0;
+
+		for (i = 0; i < env->nr_numa_nodes; i++) {
+			nn = &env->numa_nodes[i];
+			nr = max(nr, (int)perf_cpu_map__max(nn->map).cpu);
+		}
+
+		nr++;
+
+		/*
+		 * We initialize the numa_map array to prepare
+		 * it for missing cpus, which return node -1
+		 */
+		env->numa_map = malloc(nr * sizeof(int));
+		if (!env->numa_map)
+			return -1;
+
+		for (i = 0; i < nr; i++)
+			env->numa_map[i] = -1;
+
+		env->nr_numa_map = nr;
+
+		for (i = 0; i < env->nr_numa_nodes; i++) {
+			struct perf_cpu tmp;
+			unsigned int j;
+
+			nn = &env->numa_nodes[i];
+			perf_cpu_map__for_each_cpu(tmp, j, nn->map)
+				env->numa_map[tmp.cpu] = i;
+		}
+	}
+
+	return cpu.cpu >= 0 && cpu.cpu < env->nr_numa_map ? env->numa_map[cpu.cpu] : -1;
+}
+
+bool perf_env__has_pmu_mapping(struct perf_env *env, const char *pmu_name)
+{
+	char *pmu_mapping = env->pmu_mappings, *colon;
+
+	for (int i = 0; i < env->nr_pmu_mappings; ++i) {
+		if (strtoul(pmu_mapping, &colon, 0) == ULONG_MAX || *colon != ':')
+			goto out_error;
+
+		pmu_mapping = colon + 1;
+		if (strcmp(pmu_mapping, pmu_name) == 0)
+			return true;
+
+		pmu_mapping += strlen(pmu_mapping) + 1;
+	}
+out_error:
+	return false;
+}
+
+char *perf_env__find_pmu_cap(struct perf_env *env, const char *pmu_name,
+			     const char *cap)
+{
+	char *cap_eq;
+	int cap_size;
+	char **ptr;
+	int i, j;
+
+	if (!pmu_name || !cap)
+		return NULL;
+
+	cap_size = strlen(cap);
+	cap_eq = zalloc(cap_size + 2);
+	if (!cap_eq)
+		return NULL;
+
+	memcpy(cap_eq, cap, cap_size);
+	cap_eq[cap_size] = '=';
+
+	if (!strcmp(pmu_name, "cpu")) {
+		for (i = 0; i < env->nr_cpu_pmu_caps; i++) {
+			if (!strncmp(env->cpu_pmu_caps[i], cap_eq, cap_size + 1)) {
+				free(cap_eq);
+				return &env->cpu_pmu_caps[i][cap_size + 1];
+			}
+		}
+		goto out;
+	}
+
+	for (i = 0; i < env->nr_pmus_with_caps; i++) {
+		if (strcmp(env->pmu_caps[i].pmu_name, pmu_name))
+			continue;
+
+		ptr = env->pmu_caps[i].caps;
+
+		for (j = 0; j < env->pmu_caps[i].nr_caps; j++) {
+			if (!strncmp(ptr[j], cap_eq, cap_size + 1)) {
+				free(cap_eq);
+				return &ptr[j][cap_size + 1];
+			}
+		}
+	}
+
+out:
+	free(cap_eq);
+	return NULL;
+}
+
+void perf_env__find_br_cntr_info(struct perf_env *env,
+				 unsigned int *nr,
+				 unsigned int *width)
+{
+	if (nr) {
+		*nr = env->cpu_pmu_caps ? env->br_cntr_nr :
+					  env->pmu_caps->br_cntr_nr;
+	}
+
+	if (width) {
+		*width = env->cpu_pmu_caps ? env->br_cntr_width :
+					     env->pmu_caps->br_cntr_width;
+	}
+}
+
+bool perf_env__is_x86_amd_cpu(struct perf_env *env)
+{
+	static int is_amd; /* 0: Uninitialized, 1: Yes, -1: No */
+
+	if (is_amd == 0)
+		is_amd = env->cpuid && strstarts(env->cpuid, "AuthenticAMD") ? 1 : -1;
+
+	return is_amd >= 1 ? true : false;
+}
+
+bool x86__is_amd_cpu(void)
+{
+	struct perf_env env = { .total_mem = 0, };
+	bool is_amd;
+
+	perf_env__init(&env);
+	perf_env__cpuid(&env);
+	is_amd = perf_env__is_x86_amd_cpu(&env);
+	perf_env__exit(&env);
+
+	return is_amd;
+}
+
+bool perf_env__is_x86_intel_cpu(struct perf_env *env)
+{
+	static int is_intel; /* 0: Uninitialized, 1: Yes, -1: No */
+
+	if (is_intel == 0)
+		is_intel = env->cpuid && strstarts(env->cpuid, "GenuineIntel") ? 1 : -1;
+
+	return is_intel >= 1 ? true : false;
+}
+
+bool x86__is_intel_cpu(void)
+{
+	struct perf_env env = { .total_mem = 0, };
+	bool is_intel;
+
+	perf_env__init(&env);
+	perf_env__cpuid(&env);
+	is_intel = perf_env__is_x86_intel_cpu(&env);
+	perf_env__exit(&env);
+
+	return is_intel;
+}