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32 results

session.c

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  • session.c 67.08 KiB
    // SPDX-License-Identifier: GPL-2.0
    #include <errno.h>
    #include <inttypes.h>
    #include <linux/err.h>
    #include <linux/kernel.h>
    #include <linux/zalloc.h>
    #include <api/fs/fs.h>
    
    #include <byteswap.h>
    #include <unistd.h>
    #include <sys/types.h>
    #include <sys/mman.h>
    #include <perf/cpumap.h>
    
    #include "map_symbol.h"
    #include "branch.h"
    #include "debug.h"
    #include "evlist.h"
    #include "evsel.h"
    #include "memswap.h"
    #include "map.h"
    #include "symbol.h"
    #include "session.h"
    #include "tool.h"
    #include "perf_regs.h"
    #include "asm/bug.h"
    #include "auxtrace.h"
    #include "thread.h"
    #include "thread-stack.h"
    #include "sample-raw.h"
    #include "stat.h"
    #include "ui/progress.h"
    #include "../perf.h"
    #include "arch/common.h"
    #include <internal/lib.h>
    
    #ifdef HAVE_ZSTD_SUPPORT
    static int perf_session__process_compressed_event(struct perf_session *session,
    						  union perf_event *event, u64 file_offset)
    {
    	void *src;
    	size_t decomp_size, src_size;
    	u64 decomp_last_rem = 0;
    	size_t mmap_len, decomp_len = session->header.env.comp_mmap_len;
    	struct decomp *decomp, *decomp_last = session->decomp_last;
    
    	if (decomp_last) {
    		decomp_last_rem = decomp_last->size - decomp_last->head;
    		decomp_len += decomp_last_rem;
    	}
    
    	mmap_len = sizeof(struct decomp) + decomp_len;
    	decomp = mmap(NULL, mmap_len, PROT_READ|PROT_WRITE,
    		      MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
    	if (decomp == MAP_FAILED) {
    		pr_err("Couldn't allocate memory for decompression\n");
    		return -1;
    	}
    
    	decomp->file_pos = file_offset;
    	decomp->mmap_len = mmap_len;
    	decomp->head = 0;
    
    	if (decomp_last_rem) {
    		memcpy(decomp->data, &(decomp_last->data[decomp_last->head]), decomp_last_rem);
    		decomp->size = decomp_last_rem;
    	}
    
    	src = (void *)event + sizeof(struct perf_record_compressed);
    	src_size = event->pack.header.size - sizeof(struct perf_record_compressed);
    
    	decomp_size = zstd_decompress_stream(&(session->zstd_data), src, src_size,
    				&(decomp->data[decomp_last_rem]), decomp_len - decomp_last_rem);
    	if (!decomp_size) {
    		munmap(decomp, mmap_len);
    		pr_err("Couldn't decompress data\n");
    		return -1;
    	}
    
    	decomp->size += decomp_size;
    
    	if (session->decomp == NULL) {
    		session->decomp = decomp;
    		session->decomp_last = decomp;
    	} else {
    		session->decomp_last->next = decomp;
    		session->decomp_last = decomp;
    	}
    
    	pr_debug("decomp (B): %zd to %zd\n", src_size, decomp_size);
    
    	return 0;
    }
    #else /* !HAVE_ZSTD_SUPPORT */
    #define perf_session__process_compressed_event perf_session__process_compressed_event_stub
    #endif
    
    static int perf_session__deliver_event(struct perf_session *session,
    				       union perf_event *event,
    				       struct perf_tool *tool,
    				       u64 file_offset);
    
    static int perf_session__open(struct perf_session *session)
    {
    	struct perf_data *data = session->data;
    
    	if (perf_session__read_header(session) < 0) {
    		pr_err("incompatible file format (rerun with -v to learn more)\n");
    		return -1;
    	}
    
    	if (perf_data__is_pipe(data))
    		return 0;
    
    	if (perf_header__has_feat(&session->header, HEADER_STAT))
    		return 0;
    
    	if (!evlist__valid_sample_type(session->evlist)) {
    		pr_err("non matching sample_type\n");
    		return -1;
    	}
    
    	if (!evlist__valid_sample_id_all(session->evlist)) {
    		pr_err("non matching sample_id_all\n");
    		return -1;
    	}
    
    	if (!perf_evlist__valid_read_format(session->evlist)) {
    		pr_err("non matching read_format\n");
    		return -1;
    	}
    
    	return 0;
    }
    
    void perf_session__set_id_hdr_size(struct perf_session *session)
    {
    	u16 id_hdr_size = perf_evlist__id_hdr_size(session->evlist);
    
    	machines__set_id_hdr_size(&session->machines, id_hdr_size);
    }
    
    int perf_session__create_kernel_maps(struct perf_session *session)
    {
    	int ret = machine__create_kernel_maps(&session->machines.host);
    
    	if (ret >= 0)
    		ret = machines__create_guest_kernel_maps(&session->machines);
    	return ret;
    }
    
    static void perf_session__destroy_kernel_maps(struct perf_session *session)
    {
    	machines__destroy_kernel_maps(&session->machines);
    }
    
    static bool perf_session__has_comm_exec(struct perf_session *session)
    {
    	struct evsel *evsel;
    
    	evlist__for_each_entry(session->evlist, evsel) {
    		if (evsel->core.attr.comm_exec)
    			return true;
    	}
    
    	return false;
    }
    
    static void perf_session__set_comm_exec(struct perf_session *session)
    {
    	bool comm_exec = perf_session__has_comm_exec(session);
    
    	machines__set_comm_exec(&session->machines, comm_exec);
    }
    
    static int ordered_events__deliver_event(struct ordered_events *oe,
    					 struct ordered_event *event)
    {
    	struct perf_session *session = container_of(oe, struct perf_session,
    						    ordered_events);
    
    	return perf_session__deliver_event(session, event->event,
    					   session->tool, event->file_offset);
    }
    
    struct perf_session *perf_session__new(struct perf_data *data,
    				       bool repipe, struct perf_tool *tool)
    {
    	int ret = -ENOMEM;
    	struct perf_session *session = zalloc(sizeof(*session));
    
    	if (!session)
    		goto out;
    
    	session->repipe = repipe;
    	session->tool   = tool;
    	INIT_LIST_HEAD(&session->auxtrace_index);
    	machines__init(&session->machines);
    	ordered_events__init(&session->ordered_events,
    			     ordered_events__deliver_event, NULL);
    
    	perf_env__init(&session->header.env);
    	if (data) {
    		ret = perf_data__open(data);
    		if (ret < 0)
    			goto out_delete;
    
    		session->data = data;
    
    		if (perf_data__is_read(data)) {
    			ret = perf_session__open(session);
    			if (ret < 0)
    				goto out_delete;
    
    			/*
    			 * set session attributes that are present in perf.data
    			 * but not in pipe-mode.
    			 */
    			if (!data->is_pipe) {
    				perf_session__set_id_hdr_size(session);
    				perf_session__set_comm_exec(session);
    			}
    
    			perf_evlist__init_trace_event_sample_raw(session->evlist);
    
    			/* Open the directory data. */
    			if (data->is_dir) {
    				ret = perf_data__open_dir(data);
    				if (ret)
    					goto out_delete;
    			}
    
    			if (!symbol_conf.kallsyms_name &&
    			    !symbol_conf.vmlinux_name)
    				symbol_conf.kallsyms_name = perf_data__kallsyms_name(data);
    		}
    	} else  {
    		session->machines.host.env = &perf_env;
    	}
    
    	session->machines.host.single_address_space =
    		perf_env__single_address_space(session->machines.host.env);
    
    	if (!data || perf_data__is_write(data)) {
    		/*
    		 * In O_RDONLY mode this will be performed when reading the
    		 * kernel MMAP event, in perf_event__process_mmap().
    		 */
    		if (perf_session__create_kernel_maps(session) < 0)
    			pr_warning("Cannot read kernel map\n");
    	}
    
    	/*
    	 * In pipe-mode, evlist is empty until PERF_RECORD_HEADER_ATTR is
    	 * processed, so evlist__sample_id_all is not meaningful here.
    	 */
    	if ((!data || !data->is_pipe) && tool && tool->ordering_requires_timestamps &&
    	    tool->ordered_events && !evlist__sample_id_all(session->evlist)) {
    		dump_printf("WARNING: No sample_id_all support, falling back to unordered processing\n");
    		tool->ordered_events = false;
    	}
    
    	return session;
    
     out_delete:
    	perf_session__delete(session);
     out:
    	return ERR_PTR(ret);
    }
    
    static void perf_session__delete_threads(struct perf_session *session)
    {
    	machine__delete_threads(&session->machines.host);
    }
    
    static void perf_session__release_decomp_events(struct perf_session *session)
    {
    	struct decomp *next, *decomp;
    	size_t mmap_len;
    	next = session->decomp;
    	do {
    		decomp = next;
    		if (decomp == NULL)
    			break;
    		next = decomp->next;
    		mmap_len = decomp->mmap_len;
    		munmap(decomp, mmap_len);
    	} while (1);
    }
    
    void perf_session__delete(struct perf_session *session)
    {
    	if (session == NULL)
    		return;
    	auxtrace__free(session);
    	auxtrace_index__free(&session->auxtrace_index);
    	perf_session__destroy_kernel_maps(session);
    	perf_session__delete_threads(session);
    	perf_session__release_decomp_events(session);
    	perf_env__exit(&session->header.env);
    	machines__exit(&session->machines);
    	if (session->data)
    		perf_data__close(session->data);
    	free(session);
    }
    
    static int process_event_synth_tracing_data_stub(struct perf_session *session
    						 __maybe_unused,
    						 union perf_event *event
    						 __maybe_unused)
    {
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int process_event_synth_attr_stub(struct perf_tool *tool __maybe_unused,
    					 union perf_event *event __maybe_unused,
    					 struct evlist **pevlist
    					 __maybe_unused)
    {
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int process_event_synth_event_update_stub(struct perf_tool *tool __maybe_unused,
    						 union perf_event *event __maybe_unused,
    						 struct evlist **pevlist
    						 __maybe_unused)
    {
    	if (dump_trace)
    		perf_event__fprintf_event_update(event, stdout);
    
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int process_event_sample_stub(struct perf_tool *tool __maybe_unused,
    				     union perf_event *event __maybe_unused,
    				     struct perf_sample *sample __maybe_unused,
    				     struct evsel *evsel __maybe_unused,
    				     struct machine *machine __maybe_unused)
    {
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int process_event_stub(struct perf_tool *tool __maybe_unused,
    			      union perf_event *event __maybe_unused,
    			      struct perf_sample *sample __maybe_unused,
    			      struct machine *machine __maybe_unused)
    {
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int process_finished_round_stub(struct perf_tool *tool __maybe_unused,
    				       union perf_event *event __maybe_unused,
    				       struct ordered_events *oe __maybe_unused)
    {
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int process_finished_round(struct perf_tool *tool,
    				  union perf_event *event,
    				  struct ordered_events *oe);
    
    static int skipn(int fd, off_t n)
    {
    	char buf[4096];
    	ssize_t ret;
    
    	while (n > 0) {
    		ret = read(fd, buf, min(n, (off_t)sizeof(buf)));
    		if (ret <= 0)
    			return ret;
    		n -= ret;
    	}
    
    	return 0;
    }
    
    static s64 process_event_auxtrace_stub(struct perf_session *session __maybe_unused,
    				       union perf_event *event)
    {
    	dump_printf(": unhandled!\n");
    	if (perf_data__is_pipe(session->data))
    		skipn(perf_data__fd(session->data), event->auxtrace.size);
    	return event->auxtrace.size;
    }
    
    static int process_event_op2_stub(struct perf_session *session __maybe_unused,
    				  union perf_event *event __maybe_unused)
    {
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    
    static
    int process_event_thread_map_stub(struct perf_session *session __maybe_unused,
    				  union perf_event *event __maybe_unused)
    {
    	if (dump_trace)
    		perf_event__fprintf_thread_map(event, stdout);
    
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static
    int process_event_cpu_map_stub(struct perf_session *session __maybe_unused,
    			       union perf_event *event __maybe_unused)
    {
    	if (dump_trace)
    		perf_event__fprintf_cpu_map(event, stdout);
    
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static
    int process_event_stat_config_stub(struct perf_session *session __maybe_unused,
    				   union perf_event *event __maybe_unused)
    {
    	if (dump_trace)
    		perf_event__fprintf_stat_config(event, stdout);
    
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int process_stat_stub(struct perf_session *perf_session __maybe_unused,
    			     union perf_event *event)
    {
    	if (dump_trace)
    		perf_event__fprintf_stat(event, stdout);
    
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int process_stat_round_stub(struct perf_session *perf_session __maybe_unused,
    				   union perf_event *event)
    {
    	if (dump_trace)
    		perf_event__fprintf_stat_round(event, stdout);
    
    	dump_printf(": unhandled!\n");
    	return 0;
    }
    
    static int perf_session__process_compressed_event_stub(struct perf_session *session __maybe_unused,
    						       union perf_event *event __maybe_unused,
    						       u64 file_offset __maybe_unused)
    {
           dump_printf(": unhandled!\n");
           return 0;
    }
    
    void perf_tool__fill_defaults(struct perf_tool *tool)
    {
    	if (tool->sample == NULL)
    		tool->sample = process_event_sample_stub;
    	if (tool->mmap == NULL)
    		tool->mmap = process_event_stub;
    	if (tool->mmap2 == NULL)
    		tool->mmap2 = process_event_stub;
    	if (tool->comm == NULL)
    		tool->comm = process_event_stub;
    	if (tool->namespaces == NULL)
    		tool->namespaces = process_event_stub;
    	if (tool->cgroup == NULL)
    		tool->cgroup = process_event_stub;
    	if (tool->fork == NULL)
    		tool->fork = process_event_stub;
    	if (tool->exit == NULL)
    		tool->exit = process_event_stub;
    	if (tool->lost == NULL)
    		tool->lost = perf_event__process_lost;
    	if (tool->lost_samples == NULL)
    		tool->lost_samples = perf_event__process_lost_samples;
    	if (tool->aux == NULL)
    		tool->aux = perf_event__process_aux;
    	if (tool->itrace_start == NULL)
    		tool->itrace_start = perf_event__process_itrace_start;
    	if (tool->context_switch == NULL)
    		tool->context_switch = perf_event__process_switch;
    	if (tool->ksymbol == NULL)
    		tool->ksymbol = perf_event__process_ksymbol;
    	if (tool->bpf == NULL)
    		tool->bpf = perf_event__process_bpf;
    	if (tool->text_poke == NULL)
    		tool->text_poke = perf_event__process_text_poke;
    	if (tool->read == NULL)
    		tool->read = process_event_sample_stub;
    	if (tool->throttle == NULL)
    		tool->throttle = process_event_stub;
    	if (tool->unthrottle == NULL)
    		tool->unthrottle = process_event_stub;
    	if (tool->attr == NULL)
    		tool->attr = process_event_synth_attr_stub;
    	if (tool->event_update == NULL)
    		tool->event_update = process_event_synth_event_update_stub;
    	if (tool->tracing_data == NULL)
    		tool->tracing_data = process_event_synth_tracing_data_stub;
    	if (tool->build_id == NULL)
    		tool->build_id = process_event_op2_stub;
    	if (tool->finished_round == NULL) {
    		if (tool->ordered_events)
    			tool->finished_round = process_finished_round;
    		else
    			tool->finished_round = process_finished_round_stub;
    	}
    	if (tool->id_index == NULL)
    		tool->id_index = process_event_op2_stub;
    	if (tool->auxtrace_info == NULL)
    		tool->auxtrace_info = process_event_op2_stub;
    	if (tool->auxtrace == NULL)
    		tool->auxtrace = process_event_auxtrace_stub;
    	if (tool->auxtrace_error == NULL)
    		tool->auxtrace_error = process_event_op2_stub;
    	if (tool->thread_map == NULL)
    		tool->thread_map = process_event_thread_map_stub;
    	if (tool->cpu_map == NULL)
    		tool->cpu_map = process_event_cpu_map_stub;
    	if (tool->stat_config == NULL)
    		tool->stat_config = process_event_stat_config_stub;
    	if (tool->stat == NULL)
    		tool->stat = process_stat_stub;
    	if (tool->stat_round == NULL)
    		tool->stat_round = process_stat_round_stub;
    	if (tool->time_conv == NULL)
    		tool->time_conv = process_event_op2_stub;
    	if (tool->feature == NULL)
    		tool->feature = process_event_op2_stub;
    	if (tool->compressed == NULL)
    		tool->compressed = perf_session__process_compressed_event;
    }
    
    static void swap_sample_id_all(union perf_event *event, void *data)
    {
    	void *end = (void *) event + event->header.size;
    	int size = end - data;
    
    	BUG_ON(size % sizeof(u64));
    	mem_bswap_64(data, size);
    }
    
    static void perf_event__all64_swap(union perf_event *event,
    				   bool sample_id_all __maybe_unused)
    {
    	struct perf_event_header *hdr = &event->header;
    	mem_bswap_64(hdr + 1, event->header.size - sizeof(*hdr));
    }
    
    static void perf_event__comm_swap(union perf_event *event, bool sample_id_all)
    {
    	event->comm.pid = bswap_32(event->comm.pid);
    	event->comm.tid = bswap_32(event->comm.tid);
    
    	if (sample_id_all) {
    		void *data = &event->comm.comm;
    
    		data += PERF_ALIGN(strlen(data) + 1, sizeof(u64));
    		swap_sample_id_all(event, data);
    	}
    }
    
    static void perf_event__mmap_swap(union perf_event *event,
    				  bool sample_id_all)
    {
    	event->mmap.pid	  = bswap_32(event->mmap.pid);
    	event->mmap.tid	  = bswap_32(event->mmap.tid);
    	event->mmap.start = bswap_64(event->mmap.start);
    	event->mmap.len	  = bswap_64(event->mmap.len);
    	event->mmap.pgoff = bswap_64(event->mmap.pgoff);
    
    	if (sample_id_all) {
    		void *data = &event->mmap.filename;
    
    		data += PERF_ALIGN(strlen(data) + 1, sizeof(u64));
    		swap_sample_id_all(event, data);
    	}
    }
    
    static void perf_event__mmap2_swap(union perf_event *event,
    				  bool sample_id_all)
    {
    	event->mmap2.pid   = bswap_32(event->mmap2.pid);
    	event->mmap2.tid   = bswap_32(event->mmap2.tid);
    	event->mmap2.start = bswap_64(event->mmap2.start);
    	event->mmap2.len   = bswap_64(event->mmap2.len);
    	event->mmap2.pgoff = bswap_64(event->mmap2.pgoff);
    	event->mmap2.maj   = bswap_32(event->mmap2.maj);
    	event->mmap2.min   = bswap_32(event->mmap2.min);
    	event->mmap2.ino   = bswap_64(event->mmap2.ino);
    	event->mmap2.ino_generation = bswap_64(event->mmap2.ino_generation);
    
    	if (sample_id_all) {
    		void *data = &event->mmap2.filename;
    
    		data += PERF_ALIGN(strlen(data) + 1, sizeof(u64));
    		swap_sample_id_all(event, data);
    	}
    }
    static void perf_event__task_swap(union perf_event *event, bool sample_id_all)
    {
    	event->fork.pid	 = bswap_32(event->fork.pid);
    	event->fork.tid	 = bswap_32(event->fork.tid);
    	event->fork.ppid = bswap_32(event->fork.ppid);
    	event->fork.ptid = bswap_32(event->fork.ptid);
    	event->fork.time = bswap_64(event->fork.time);
    
    	if (sample_id_all)
    		swap_sample_id_all(event, &event->fork + 1);
    }
    
    static void perf_event__read_swap(union perf_event *event, bool sample_id_all)
    {
    	event->read.pid		 = bswap_32(event->read.pid);
    	event->read.tid		 = bswap_32(event->read.tid);
    	event->read.value	 = bswap_64(event->read.value);
    	event->read.time_enabled = bswap_64(event->read.time_enabled);
    	event->read.time_running = bswap_64(event->read.time_running);
    	event->read.id		 = bswap_64(event->read.id);
    
    	if (sample_id_all)
    		swap_sample_id_all(event, &event->read + 1);
    }
    
    static void perf_event__aux_swap(union perf_event *event, bool sample_id_all)
    {
    	event->aux.aux_offset = bswap_64(event->aux.aux_offset);
    	event->aux.aux_size   = bswap_64(event->aux.aux_size);
    	event->aux.flags      = bswap_64(event->aux.flags);
    
    	if (sample_id_all)
    		swap_sample_id_all(event, &event->aux + 1);
    }
    
    static void perf_event__itrace_start_swap(union perf_event *event,
    					  bool sample_id_all)
    {
    	event->itrace_start.pid	 = bswap_32(event->itrace_start.pid);
    	event->itrace_start.tid	 = bswap_32(event->itrace_start.tid);
    
    	if (sample_id_all)
    		swap_sample_id_all(event, &event->itrace_start + 1);
    }
    
    static void perf_event__switch_swap(union perf_event *event, bool sample_id_all)
    {
    	if (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE) {
    		event->context_switch.next_prev_pid =
    				bswap_32(event->context_switch.next_prev_pid);
    		event->context_switch.next_prev_tid =
    				bswap_32(event->context_switch.next_prev_tid);
    	}
    
    	if (sample_id_all)
    		swap_sample_id_all(event, &event->context_switch + 1);
    }
    
    static void perf_event__text_poke_swap(union perf_event *event, bool sample_id_all)
    {
    	event->text_poke.addr    = bswap_64(event->text_poke.addr);
    	event->text_poke.old_len = bswap_16(event->text_poke.old_len);
    	event->text_poke.new_len = bswap_16(event->text_poke.new_len);
    
    	if (sample_id_all) {
    		size_t len = sizeof(event->text_poke.old_len) +
    			     sizeof(event->text_poke.new_len) +
    			     event->text_poke.old_len +
    			     event->text_poke.new_len;
    		void *data = &event->text_poke.old_len;
    
    		data += PERF_ALIGN(len, sizeof(u64));
    		swap_sample_id_all(event, data);
    	}
    }
    
    static void perf_event__throttle_swap(union perf_event *event,
    				      bool sample_id_all)
    {
    	event->throttle.time	  = bswap_64(event->throttle.time);
    	event->throttle.id	  = bswap_64(event->throttle.id);
    	event->throttle.stream_id = bswap_64(event->throttle.stream_id);
    
    	if (sample_id_all)
    		swap_sample_id_all(event, &event->throttle + 1);
    }
    
    static void perf_event__namespaces_swap(union perf_event *event,
    					bool sample_id_all)
    {
    	u64 i;
    
    	event->namespaces.pid		= bswap_32(event->namespaces.pid);
    	event->namespaces.tid		= bswap_32(event->namespaces.tid);
    	event->namespaces.nr_namespaces	= bswap_64(event->namespaces.nr_namespaces);
    
    	for (i = 0; i < event->namespaces.nr_namespaces; i++) {
    		struct perf_ns_link_info *ns = &event->namespaces.link_info[i];
    
    		ns->dev = bswap_64(ns->dev);
    		ns->ino = bswap_64(ns->ino);
    	}
    
    	if (sample_id_all)
    		swap_sample_id_all(event, &event->namespaces.link_info[i]);
    }
    
    static u8 revbyte(u8 b)
    {
    	int rev = (b >> 4) | ((b & 0xf) << 4);
    	rev = ((rev & 0xcc) >> 2) | ((rev & 0x33) << 2);
    	rev = ((rev & 0xaa) >> 1) | ((rev & 0x55) << 1);
    	return (u8) rev;
    }
    
    /*
     * XXX this is hack in attempt to carry flags bitfield
     * through endian village. ABI says:
     *
     * Bit-fields are allocated from right to left (least to most significant)
     * on little-endian implementations and from left to right (most to least
     * significant) on big-endian implementations.
     *
     * The above seems to be byte specific, so we need to reverse each
     * byte of the bitfield. 'Internet' also says this might be implementation
     * specific and we probably need proper fix and carry perf_event_attr
     * bitfield flags in separate data file FEAT_ section. Thought this seems
     * to work for now.
     */
    static void swap_bitfield(u8 *p, unsigned len)
    {
    	unsigned i;
    
    	for (i = 0; i < len; i++) {
    		*p = revbyte(*p);
    		p++;
    	}
    }
    
    /* exported for swapping attributes in file header */
    void perf_event__attr_swap(struct perf_event_attr *attr)
    {
    	attr->type		= bswap_32(attr->type);
    	attr->size		= bswap_32(attr->size);
    
    #define bswap_safe(f, n) 					\
    	(attr->size > (offsetof(struct perf_event_attr, f) + 	\
    		       sizeof(attr->f) * (n)))
    #define bswap_field(f, sz) 			\
    do { 						\
    	if (bswap_safe(f, 0))			\
    		attr->f = bswap_##sz(attr->f);	\
    } while(0)
    #define bswap_field_16(f) bswap_field(f, 16)
    #define bswap_field_32(f) bswap_field(f, 32)
    #define bswap_field_64(f) bswap_field(f, 64)
    
    	bswap_field_64(config);
    	bswap_field_64(sample_period);
    	bswap_field_64(sample_type);
    	bswap_field_64(read_format);
    	bswap_field_32(wakeup_events);
    	bswap_field_32(bp_type);
    	bswap_field_64(bp_addr);
    	bswap_field_64(bp_len);
    	bswap_field_64(branch_sample_type);
    	bswap_field_64(sample_regs_user);
    	bswap_field_32(sample_stack_user);
    	bswap_field_32(aux_watermark);
    	bswap_field_16(sample_max_stack);
    	bswap_field_32(aux_sample_size);
    
    	/*
    	 * After read_format are bitfields. Check read_format because
    	 * we are unable to use offsetof on bitfield.
    	 */
    	if (bswap_safe(read_format, 1))
    		swap_bitfield((u8 *) (&attr->read_format + 1),
    			      sizeof(u64));
    #undef bswap_field_64
    #undef bswap_field_32
    #undef bswap_field
    #undef bswap_safe
    }
    
    static void perf_event__hdr_attr_swap(union perf_event *event,
    				      bool sample_id_all __maybe_unused)
    {
    	size_t size;
    
    	perf_event__attr_swap(&event->attr.attr);
    
    	size = event->header.size;
    	size -= (void *)&event->attr.id - (void *)event;
    	mem_bswap_64(event->attr.id, size);
    }
    
    static void perf_event__event_update_swap(union perf_event *event,
    					  bool sample_id_all __maybe_unused)
    {
    	event->event_update.type = bswap_64(event->event_update.type);
    	event->event_update.id   = bswap_64(event->event_update.id);
    }
    
    static void perf_event__event_type_swap(union perf_event *event,
    					bool sample_id_all __maybe_unused)
    {
    	event->event_type.event_type.event_id =
    		bswap_64(event->event_type.event_type.event_id);
    }
    
    static void perf_event__tracing_data_swap(union perf_event *event,
    					  bool sample_id_all __maybe_unused)
    {
    	event->tracing_data.size = bswap_32(event->tracing_data.size);
    }
    
    static void perf_event__auxtrace_info_swap(union perf_event *event,
    					   bool sample_id_all __maybe_unused)
    {
    	size_t size;
    
    	event->auxtrace_info.type = bswap_32(event->auxtrace_info.type);
    
    	size = event->header.size;
    	size -= (void *)&event->auxtrace_info.priv - (void *)event;
    	mem_bswap_64(event->auxtrace_info.priv, size);
    }
    
    static void perf_event__auxtrace_swap(union perf_event *event,
    				      bool sample_id_all __maybe_unused)
    {
    	event->auxtrace.size      = bswap_64(event->auxtrace.size);
    	event->auxtrace.offset    = bswap_64(event->auxtrace.offset);
    	event->auxtrace.reference = bswap_64(event->auxtrace.reference);
    	event->auxtrace.idx       = bswap_32(event->auxtrace.idx);
    	event->auxtrace.tid       = bswap_32(event->auxtrace.tid);
    	event->auxtrace.cpu       = bswap_32(event->auxtrace.cpu);
    }
    
    static void perf_event__auxtrace_error_swap(union perf_event *event,
    					    bool sample_id_all __maybe_unused)
    {
    	event->auxtrace_error.type = bswap_32(event->auxtrace_error.type);
    	event->auxtrace_error.code = bswap_32(event->auxtrace_error.code);
    	event->auxtrace_error.cpu  = bswap_32(event->auxtrace_error.cpu);
    	event->auxtrace_error.pid  = bswap_32(event->auxtrace_error.pid);
    	event->auxtrace_error.tid  = bswap_32(event->auxtrace_error.tid);
    	event->auxtrace_error.fmt  = bswap_32(event->auxtrace_error.fmt);
    	event->auxtrace_error.ip   = bswap_64(event->auxtrace_error.ip);
    	if (event->auxtrace_error.fmt)
    		event->auxtrace_error.time = bswap_64(event->auxtrace_error.time);
    }
    
    static void perf_event__thread_map_swap(union perf_event *event,
    					bool sample_id_all __maybe_unused)
    {
    	unsigned i;
    
    	event->thread_map.nr = bswap_64(event->thread_map.nr);
    
    	for (i = 0; i < event->thread_map.nr; i++)
    		event->thread_map.entries[i].pid = bswap_64(event->thread_map.entries[i].pid);
    }
    
    static void perf_event__cpu_map_swap(union perf_event *event,
    				     bool sample_id_all __maybe_unused)
    {
    	struct perf_record_cpu_map_data *data = &event->cpu_map.data;
    	struct cpu_map_entries *cpus;
    	struct perf_record_record_cpu_map *mask;
    	unsigned i;
    
    	data->type = bswap_64(data->type);
    
    	switch (data->type) {
    	case PERF_CPU_MAP__CPUS:
    		cpus = (struct cpu_map_entries *)data->data;
    
    		cpus->nr = bswap_16(cpus->nr);
    
    		for (i = 0; i < cpus->nr; i++)
    			cpus->cpu[i] = bswap_16(cpus->cpu[i]);
    		break;
    	case PERF_CPU_MAP__MASK:
    		mask = (struct perf_record_record_cpu_map *)data->data;
    
    		mask->nr = bswap_16(mask->nr);
    		mask->long_size = bswap_16(mask->long_size);
    
    		switch (mask->long_size) {
    		case 4: mem_bswap_32(&mask->mask, mask->nr); break;
    		case 8: mem_bswap_64(&mask->mask, mask->nr); break;
    		default:
    			pr_err("cpu_map swap: unsupported long size\n");
    		}
    	default:
    		break;
    	}
    }
    
    static void perf_event__stat_config_swap(union perf_event *event,
    					 bool sample_id_all __maybe_unused)
    {
    	u64 size;
    
    	size  = event->stat_config.nr * sizeof(event->stat_config.data[0]);
    	size += 1; /* nr item itself */
    	mem_bswap_64(&event->stat_config.nr, size);
    }
    
    static void perf_event__stat_swap(union perf_event *event,
    				  bool sample_id_all __maybe_unused)
    {
    	event->stat.id     = bswap_64(event->stat.id);
    	event->stat.thread = bswap_32(event->stat.thread);
    	event->stat.cpu    = bswap_32(event->stat.cpu);
    	event->stat.val    = bswap_64(event->stat.val);
    	event->stat.ena    = bswap_64(event->stat.ena);
    	event->stat.run    = bswap_64(event->stat.run);
    }
    
    static void perf_event__stat_round_swap(union perf_event *event,
    					bool sample_id_all __maybe_unused)
    {
    	event->stat_round.type = bswap_64(event->stat_round.type);
    	event->stat_round.time = bswap_64(event->stat_round.time);
    }
    
    typedef void (*perf_event__swap_op)(union perf_event *event,
    				    bool sample_id_all);
    
    static perf_event__swap_op perf_event__swap_ops[] = {
    	[PERF_RECORD_MMAP]		  = perf_event__mmap_swap,
    	[PERF_RECORD_MMAP2]		  = perf_event__mmap2_swap,
    	[PERF_RECORD_COMM]		  = perf_event__comm_swap,
    	[PERF_RECORD_FORK]		  = perf_event__task_swap,
    	[PERF_RECORD_EXIT]		  = perf_event__task_swap,
    	[PERF_RECORD_LOST]		  = perf_event__all64_swap,
    	[PERF_RECORD_READ]		  = perf_event__read_swap,
    	[PERF_RECORD_THROTTLE]		  = perf_event__throttle_swap,
    	[PERF_RECORD_UNTHROTTLE]	  = perf_event__throttle_swap,
    	[PERF_RECORD_SAMPLE]		  = perf_event__all64_swap,
    	[PERF_RECORD_AUX]		  = perf_event__aux_swap,
    	[PERF_RECORD_ITRACE_START]	  = perf_event__itrace_start_swap,
    	[PERF_RECORD_LOST_SAMPLES]	  = perf_event__all64_swap,
    	[PERF_RECORD_SWITCH]		  = perf_event__switch_swap,
    	[PERF_RECORD_SWITCH_CPU_WIDE]	  = perf_event__switch_swap,
    	[PERF_RECORD_NAMESPACES]	  = perf_event__namespaces_swap,
    	[PERF_RECORD_TEXT_POKE]		  = perf_event__text_poke_swap,
    	[PERF_RECORD_HEADER_ATTR]	  = perf_event__hdr_attr_swap,
    	[PERF_RECORD_HEADER_EVENT_TYPE]	  = perf_event__event_type_swap,
    	[PERF_RECORD_HEADER_TRACING_DATA] = perf_event__tracing_data_swap,
    	[PERF_RECORD_HEADER_BUILD_ID]	  = NULL,
    	[PERF_RECORD_ID_INDEX]		  = perf_event__all64_swap,
    	[PERF_RECORD_AUXTRACE_INFO]	  = perf_event__auxtrace_info_swap,
    	[PERF_RECORD_AUXTRACE]		  = perf_event__auxtrace_swap,
    	[PERF_RECORD_AUXTRACE_ERROR]	  = perf_event__auxtrace_error_swap,
    	[PERF_RECORD_THREAD_MAP]	  = perf_event__thread_map_swap,
    	[PERF_RECORD_CPU_MAP]		  = perf_event__cpu_map_swap,
    	[PERF_RECORD_STAT_CONFIG]	  = perf_event__stat_config_swap,
    	[PERF_RECORD_STAT]		  = perf_event__stat_swap,
    	[PERF_RECORD_STAT_ROUND]	  = perf_event__stat_round_swap,
    	[PERF_RECORD_EVENT_UPDATE]	  = perf_event__event_update_swap,
    	[PERF_RECORD_TIME_CONV]		  = perf_event__all64_swap,
    	[PERF_RECORD_HEADER_MAX]	  = NULL,
    };
    
    /*
     * When perf record finishes a pass on every buffers, it records this pseudo
     * event.
     * We record the max timestamp t found in the pass n.
     * Assuming these timestamps are monotonic across cpus, we know that if
     * a buffer still has events with timestamps below t, they will be all
     * available and then read in the pass n + 1.
     * Hence when we start to read the pass n + 2, we can safely flush every
     * events with timestamps below t.
     *
     *    ============ PASS n =================
     *       CPU 0         |   CPU 1
     *                     |
     *    cnt1 timestamps  |   cnt2 timestamps
     *          1          |         2
     *          2          |         3
     *          -          |         4  <--- max recorded
     *
     *    ============ PASS n + 1 ==============
     *       CPU 0         |   CPU 1
     *                     |
     *    cnt1 timestamps  |   cnt2 timestamps
     *          3          |         5
     *          4          |         6
     *          5          |         7 <---- max recorded
     *
     *      Flush every events below timestamp 4
     *
     *    ============ PASS n + 2 ==============
     *       CPU 0         |   CPU 1
     *                     |
     *    cnt1 timestamps  |   cnt2 timestamps
     *          6          |         8
     *          7          |         9
     *          -          |         10
     *
     *      Flush every events below timestamp 7
     *      etc...
     */
    static int process_finished_round(struct perf_tool *tool __maybe_unused,
    				  union perf_event *event __maybe_unused,
    				  struct ordered_events *oe)
    {
    	if (dump_trace)
    		fprintf(stdout, "\n");
    	return ordered_events__flush(oe, OE_FLUSH__ROUND);
    }
    
    int perf_session__queue_event(struct perf_session *s, union perf_event *event,
    			      u64 timestamp, u64 file_offset)
    {
    	return ordered_events__queue(&s->ordered_events, event, timestamp, file_offset);
    }
    
    static void callchain__lbr_callstack_printf(struct perf_sample *sample)
    {
    	struct ip_callchain *callchain = sample->callchain;
    	struct branch_stack *lbr_stack = sample->branch_stack;
    	struct branch_entry *entries = perf_sample__branch_entries(sample);
    	u64 kernel_callchain_nr = callchain->nr;
    	unsigned int i;
    
    	for (i = 0; i < kernel_callchain_nr; i++) {
    		if (callchain->ips[i] == PERF_CONTEXT_USER)
    			break;
    	}
    
    	if ((i != kernel_callchain_nr) && lbr_stack->nr) {
    		u64 total_nr;
    		/*
    		 * LBR callstack can only get user call chain,
    		 * i is kernel call chain number,
    		 * 1 is PERF_CONTEXT_USER.
    		 *
    		 * The user call chain is stored in LBR registers.
    		 * LBR are pair registers. The caller is stored
    		 * in "from" register, while the callee is stored
    		 * in "to" register.
    		 * For example, there is a call stack
    		 * "A"->"B"->"C"->"D".
    		 * The LBR registers will recorde like
    		 * "C"->"D", "B"->"C", "A"->"B".
    		 * So only the first "to" register and all "from"
    		 * registers are needed to construct the whole stack.
    		 */
    		total_nr = i + 1 + lbr_stack->nr + 1;
    		kernel_callchain_nr = i + 1;
    
    		printf("... LBR call chain: nr:%" PRIu64 "\n", total_nr);
    
    		for (i = 0; i < kernel_callchain_nr; i++)
    			printf("..... %2d: %016" PRIx64 "\n",
    			       i, callchain->ips[i]);
    
    		printf("..... %2d: %016" PRIx64 "\n",
    		       (int)(kernel_callchain_nr), entries[0].to);
    		for (i = 0; i < lbr_stack->nr; i++)
    			printf("..... %2d: %016" PRIx64 "\n",
    			       (int)(i + kernel_callchain_nr + 1), entries[i].from);
    	}
    }
    
    static void callchain__printf(struct evsel *evsel,
    			      struct perf_sample *sample)
    {
    	unsigned int i;
    	struct ip_callchain *callchain = sample->callchain;
    
    	if (evsel__has_branch_callstack(evsel))
    		callchain__lbr_callstack_printf(sample);
    
    	printf("... FP chain: nr:%" PRIu64 "\n", callchain->nr);
    
    	for (i = 0; i < callchain->nr; i++)
    		printf("..... %2d: %016" PRIx64 "\n",
    		       i, callchain->ips[i]);
    }
    
    static void branch_stack__printf(struct perf_sample *sample, bool callstack)
    {
    	struct branch_entry *entries = perf_sample__branch_entries(sample);
    	uint64_t i;
    
    	printf("%s: nr:%" PRIu64 "\n",
    		!callstack ? "... branch stack" : "... branch callstack",
    		sample->branch_stack->nr);
    
    	for (i = 0; i < sample->branch_stack->nr; i++) {
    		struct branch_entry *e = &entries[i];
    
    		if (!callstack) {
    			printf("..... %2"PRIu64": %016" PRIx64 " -> %016" PRIx64 " %hu cycles %s%s%s%s %x\n",
    				i, e->from, e->to,
    				(unsigned short)e->flags.cycles,
    				e->flags.mispred ? "M" : " ",
    				e->flags.predicted ? "P" : " ",
    				e->flags.abort ? "A" : " ",
    				e->flags.in_tx ? "T" : " ",
    				(unsigned)e->flags.reserved);
    		} else {
    			printf("..... %2"PRIu64": %016" PRIx64 "\n",
    				i, i > 0 ? e->from : e->to);
    		}
    	}
    }
    
    static void regs_dump__printf(u64 mask, u64 *regs)
    {
    	unsigned rid, i = 0;
    
    	for_each_set_bit(rid, (unsigned long *) &mask, sizeof(mask) * 8) {
    		u64 val = regs[i++];
    
    		printf(".... %-5s 0x%016" PRIx64 "\n",
    		       perf_reg_name(rid), val);
    	}
    }
    
    static const char *regs_abi[] = {
    	[PERF_SAMPLE_REGS_ABI_NONE] = "none",
    	[PERF_SAMPLE_REGS_ABI_32] = "32-bit",
    	[PERF_SAMPLE_REGS_ABI_64] = "64-bit",
    };
    
    static inline const char *regs_dump_abi(struct regs_dump *d)
    {
    	if (d->abi > PERF_SAMPLE_REGS_ABI_64)
    		return "unknown";
    
    	return regs_abi[d->abi];
    }
    
    static void regs__printf(const char *type, struct regs_dump *regs)
    {
    	u64 mask = regs->mask;
    
    	printf("... %s regs: mask 0x%" PRIx64 " ABI %s\n",
    	       type,
    	       mask,
    	       regs_dump_abi(regs));
    
    	regs_dump__printf(mask, regs->regs);
    }
    
    static void regs_user__printf(struct perf_sample *sample)
    {
    	struct regs_dump *user_regs = &sample->user_regs;
    
    	if (user_regs->regs)
    		regs__printf("user", user_regs);
    }
    
    static void regs_intr__printf(struct perf_sample *sample)
    {
    	struct regs_dump *intr_regs = &sample->intr_regs;
    
    	if (intr_regs->regs)
    		regs__printf("intr", intr_regs);
    }
    
    static void stack_user__printf(struct stack_dump *dump)
    {
    	printf("... ustack: size %" PRIu64 ", offset 0x%x\n",
    	       dump->size, dump->offset);
    }
    
    static void perf_evlist__print_tstamp(struct evlist *evlist,
    				       union perf_event *event,
    				       struct perf_sample *sample)
    {
    	u64 sample_type = __evlist__combined_sample_type(evlist);
    
    	if (event->header.type != PERF_RECORD_SAMPLE &&
    	    !evlist__sample_id_all(evlist)) {
    		fputs("-1 -1 ", stdout);
    		return;
    	}
    
    	if ((sample_type & PERF_SAMPLE_CPU))
    		printf("%u ", sample->cpu);
    
    	if (sample_type & PERF_SAMPLE_TIME)
    		printf("%" PRIu64 " ", sample->time);
    }
    
    static void sample_read__printf(struct perf_sample *sample, u64 read_format)
    {
    	printf("... sample_read:\n");
    
    	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
    		printf("...... time enabled %016" PRIx64 "\n",
    		       sample->read.time_enabled);
    
    	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
    		printf("...... time running %016" PRIx64 "\n",
    		       sample->read.time_running);
    
    	if (read_format & PERF_FORMAT_GROUP) {
    		u64 i;
    
    		printf(".... group nr %" PRIu64 "\n", sample->read.group.nr);
    
    		for (i = 0; i < sample->read.group.nr; i++) {
    			struct sample_read_value *value;
    
    			value = &sample->read.group.values[i];
    			printf("..... id %016" PRIx64
    			       ", value %016" PRIx64 "\n",
    			       value->id, value->value);
    		}
    	} else
    		printf("..... id %016" PRIx64 ", value %016" PRIx64 "\n",
    			sample->read.one.id, sample->read.one.value);
    }
    
    static void dump_event(struct evlist *evlist, union perf_event *event,
    		       u64 file_offset, struct perf_sample *sample)
    {
    	if (!dump_trace)
    		return;
    
    	printf("\n%#" PRIx64 " [%#x]: event: %d\n",
    	       file_offset, event->header.size, event->header.type);
    
    	trace_event(event);
    	if (event->header.type == PERF_RECORD_SAMPLE && evlist->trace_event_sample_raw)
    		evlist->trace_event_sample_raw(evlist, event, sample);
    
    	if (sample)
    		perf_evlist__print_tstamp(evlist, event, sample);
    
    	printf("%#" PRIx64 " [%#x]: PERF_RECORD_%s", file_offset,
    	       event->header.size, perf_event__name(event->header.type));
    }
    
    static void dump_sample(struct evsel *evsel, union perf_event *event,
    			struct perf_sample *sample)
    {
    	u64 sample_type;
    
    	if (!dump_trace)
    		return;
    
    	printf("(IP, 0x%x): %d/%d: %#" PRIx64 " period: %" PRIu64 " addr: %#" PRIx64 "\n",
    	       event->header.misc, sample->pid, sample->tid, sample->ip,
    	       sample->period, sample->addr);
    
    	sample_type = evsel->core.attr.sample_type;
    
    	if (evsel__has_callchain(evsel))
    		callchain__printf(evsel, sample);
    
    	if (evsel__has_br_stack(evsel))
    		branch_stack__printf(sample, evsel__has_branch_callstack(evsel));
    
    	if (sample_type & PERF_SAMPLE_REGS_USER)
    		regs_user__printf(sample);
    
    	if (sample_type & PERF_SAMPLE_REGS_INTR)
    		regs_intr__printf(sample);
    
    	if (sample_type & PERF_SAMPLE_STACK_USER)
    		stack_user__printf(&sample->user_stack);
    
    	if (sample_type & PERF_SAMPLE_WEIGHT)
    		printf("... weight: %" PRIu64 "\n", sample->weight);
    
    	if (sample_type & PERF_SAMPLE_DATA_SRC)
    		printf(" . data_src: 0x%"PRIx64"\n", sample->data_src);
    
    	if (sample_type & PERF_SAMPLE_PHYS_ADDR)
    		printf(" .. phys_addr: 0x%"PRIx64"\n", sample->phys_addr);
    
    	if (sample_type & PERF_SAMPLE_TRANSACTION)
    		printf("... transaction: %" PRIx64 "\n", sample->transaction);
    
    	if (sample_type & PERF_SAMPLE_READ)
    		sample_read__printf(sample, evsel->core.attr.read_format);
    }
    
    static void dump_read(struct evsel *evsel, union perf_event *event)
    {
    	struct perf_record_read *read_event = &event->read;
    	u64 read_format;
    
    	if (!dump_trace)
    		return;
    
    	printf(": %d %d %s %" PRI_lu64 "\n", event->read.pid, event->read.tid,
    	       evsel__name(evsel), event->read.value);
    
    	if (!evsel)
    		return;
    
    	read_format = evsel->core.attr.read_format;
    
    	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
    		printf("... time enabled : %" PRI_lu64 "\n", read_event->time_enabled);
    
    	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
    		printf("... time running : %" PRI_lu64 "\n", read_event->time_running);
    
    	if (read_format & PERF_FORMAT_ID)
    		printf("... id           : %" PRI_lu64 "\n", read_event->id);
    }
    
    static struct machine *machines__find_for_cpumode(struct machines *machines,
    					       union perf_event *event,
    					       struct perf_sample *sample)
    {
    	struct machine *machine;
    
    	if (perf_guest &&
    	    ((sample->cpumode == PERF_RECORD_MISC_GUEST_KERNEL) ||
    	     (sample->cpumode == PERF_RECORD_MISC_GUEST_USER))) {
    		u32 pid;
    
    		if (event->header.type == PERF_RECORD_MMAP
    		    || event->header.type == PERF_RECORD_MMAP2)
    			pid = event->mmap.pid;
    		else
    			pid = sample->pid;
    
    		machine = machines__find(machines, pid);
    		if (!machine)
    			machine = machines__findnew(machines, DEFAULT_GUEST_KERNEL_ID);
    		return machine;
    	}
    
    	return &machines->host;
    }
    
    static int deliver_sample_value(struct evlist *evlist,
    				struct perf_tool *tool,
    				union perf_event *event,
    				struct perf_sample *sample,
    				struct sample_read_value *v,
    				struct machine *machine)
    {
    	struct perf_sample_id *sid = perf_evlist__id2sid(evlist, v->id);
    	struct evsel *evsel;
    
    	if (sid) {
    		sample->id     = v->id;
    		sample->period = v->value - sid->period;
    		sid->period    = v->value;
    	}
    
    	if (!sid || sid->evsel == NULL) {
    		++evlist->stats.nr_unknown_id;
    		return 0;
    	}
    
    	/*
    	 * There's no reason to deliver sample
    	 * for zero period, bail out.
    	 */
    	if (!sample->period)
    		return 0;
    
    	evsel = container_of(sid->evsel, struct evsel, core);
    	return tool->sample(tool, event, sample, evsel, machine);
    }
    
    static int deliver_sample_group(struct evlist *evlist,
    				struct perf_tool *tool,
    				union  perf_event *event,
    				struct perf_sample *sample,
    				struct machine *machine)
    {
    	int ret = -EINVAL;
    	u64 i;
    
    	for (i = 0; i < sample->read.group.nr; i++) {
    		ret = deliver_sample_value(evlist, tool, event, sample,
    					   &sample->read.group.values[i],
    					   machine);
    		if (ret)
    			break;
    	}
    
    	return ret;
    }
    
    static int
     perf_evlist__deliver_sample(struct evlist *evlist,
    			     struct perf_tool *tool,
    			     union  perf_event *event,
    			     struct perf_sample *sample,
    			     struct evsel *evsel,
    			     struct machine *machine)
    {
    	/* We know evsel != NULL. */
    	u64 sample_type = evsel->core.attr.sample_type;
    	u64 read_format = evsel->core.attr.read_format;
    
    	/* Standard sample delivery. */
    	if (!(sample_type & PERF_SAMPLE_READ))
    		return tool->sample(tool, event, sample, evsel, machine);
    
    	/* For PERF_SAMPLE_READ we have either single or group mode. */
    	if (read_format & PERF_FORMAT_GROUP)
    		return deliver_sample_group(evlist, tool, event, sample,
    					    machine);
    	else
    		return deliver_sample_value(evlist, tool, event, sample,
    					    &sample->read.one, machine);
    }
    
    static int machines__deliver_event(struct machines *machines,
    				   struct evlist *evlist,
    				   union perf_event *event,
    				   struct perf_sample *sample,
    				   struct perf_tool *tool, u64 file_offset)
    {
    	struct evsel *evsel;
    	struct machine *machine;
    
    	dump_event(evlist, event, file_offset, sample);
    
    	evsel = perf_evlist__id2evsel(evlist, sample->id);
    
    	machine = machines__find_for_cpumode(machines, event, sample);
    
    	switch (event->header.type) {
    	case PERF_RECORD_SAMPLE:
    		if (evsel == NULL) {
    			++evlist->stats.nr_unknown_id;
    			return 0;
    		}
    		dump_sample(evsel, event, sample);
    		if (machine == NULL) {
    			++evlist->stats.nr_unprocessable_samples;
    			return 0;
    		}
    		return perf_evlist__deliver_sample(evlist, tool, event, sample, evsel, machine);
    	case PERF_RECORD_MMAP:
    		return tool->mmap(tool, event, sample, machine);
    	case PERF_RECORD_MMAP2:
    		if (event->header.misc & PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT)
    			++evlist->stats.nr_proc_map_timeout;
    		return tool->mmap2(tool, event, sample, machine);
    	case PERF_RECORD_COMM:
    		return tool->comm(tool, event, sample, machine);
    	case PERF_RECORD_NAMESPACES:
    		return tool->namespaces(tool, event, sample, machine);
    	case PERF_RECORD_CGROUP:
    		return tool->cgroup(tool, event, sample, machine);
    	case PERF_RECORD_FORK:
    		return tool->fork(tool, event, sample, machine);
    	case PERF_RECORD_EXIT:
    		return tool->exit(tool, event, sample, machine);
    	case PERF_RECORD_LOST:
    		if (tool->lost == perf_event__process_lost)
    			evlist->stats.total_lost += event->lost.lost;
    		return tool->lost(tool, event, sample, machine);
    	case PERF_RECORD_LOST_SAMPLES:
    		if (tool->lost_samples == perf_event__process_lost_samples)
    			evlist->stats.total_lost_samples += event->lost_samples.lost;
    		return tool->lost_samples(tool, event, sample, machine);
    	case PERF_RECORD_READ:
    		dump_read(evsel, event);
    		return tool->read(tool, event, sample, evsel, machine);
    	case PERF_RECORD_THROTTLE:
    		return tool->throttle(tool, event, sample, machine);
    	case PERF_RECORD_UNTHROTTLE:
    		return tool->unthrottle(tool, event, sample, machine);
    	case PERF_RECORD_AUX:
    		if (tool->aux == perf_event__process_aux) {
    			if (event->aux.flags & PERF_AUX_FLAG_TRUNCATED)
    				evlist->stats.total_aux_lost += 1;
    			if (event->aux.flags & PERF_AUX_FLAG_PARTIAL)
    				evlist->stats.total_aux_partial += 1;
    		}
    		return tool->aux(tool, event, sample, machine);
    	case PERF_RECORD_ITRACE_START:
    		return tool->itrace_start(tool, event, sample, machine);
    	case PERF_RECORD_SWITCH:
    	case PERF_RECORD_SWITCH_CPU_WIDE:
    		return tool->context_switch(tool, event, sample, machine);
    	case PERF_RECORD_KSYMBOL:
    		return tool->ksymbol(tool, event, sample, machine);
    	case PERF_RECORD_BPF_EVENT:
    		return tool->bpf(tool, event, sample, machine);
    	case PERF_RECORD_TEXT_POKE:
    		return tool->text_poke(tool, event, sample, machine);
    	default:
    		++evlist->stats.nr_unknown_events;
    		return -1;
    	}
    }
    
    static int perf_session__deliver_event(struct perf_session *session,
    				       union perf_event *event,
    				       struct perf_tool *tool,
    				       u64 file_offset)
    {
    	struct perf_sample sample;
    	int ret;
    
    	ret = perf_evlist__parse_sample(session->evlist, event, &sample);
    	if (ret) {
    		pr_err("Can't parse sample, err = %d\n", ret);
    		return ret;
    	}
    
    	ret = auxtrace__process_event(session, event, &sample, tool);
    	if (ret < 0)
    		return ret;
    	if (ret > 0)
    		return 0;
    
    	ret = machines__deliver_event(&session->machines, session->evlist,
    				      event, &sample, tool, file_offset);
    
    	if (dump_trace && sample.aux_sample.size)
    		auxtrace__dump_auxtrace_sample(session, &sample);
    
    	return ret;
    }
    
    static s64 perf_session__process_user_event(struct perf_session *session,
    					    union perf_event *event,
    					    u64 file_offset)
    {
    	struct ordered_events *oe = &session->ordered_events;
    	struct perf_tool *tool = session->tool;
    	struct perf_sample sample = { .time = 0, };
    	int fd = perf_data__fd(session->data);
    	int err;
    
    	if (event->header.type != PERF_RECORD_COMPRESSED ||
    	    tool->compressed == perf_session__process_compressed_event_stub)
    		dump_event(session->evlist, event, file_offset, &sample);
    
    	/* These events are processed right away */
    	switch (event->header.type) {
    	case PERF_RECORD_HEADER_ATTR:
    		err = tool->attr(tool, event, &session->evlist);
    		if (err == 0) {
    			perf_session__set_id_hdr_size(session);
    			perf_session__set_comm_exec(session);
    		}
    		return err;
    	case PERF_RECORD_EVENT_UPDATE:
    		return tool->event_update(tool, event, &session->evlist);
    	case PERF_RECORD_HEADER_EVENT_TYPE:
    		/*
    		 * Depreceated, but we need to handle it for sake
    		 * of old data files create in pipe mode.
    		 */
    		return 0;
    	case PERF_RECORD_HEADER_TRACING_DATA:
    		/*
    		 * Setup for reading amidst mmap, but only when we
    		 * are in 'file' mode. The 'pipe' fd is in proper
    		 * place already.
    		 */
    		if (!perf_data__is_pipe(session->data))
    			lseek(fd, file_offset, SEEK_SET);
    		return tool->tracing_data(session, event);
    	case PERF_RECORD_HEADER_BUILD_ID:
    		return tool->build_id(session, event);
    	case PERF_RECORD_FINISHED_ROUND:
    		return tool->finished_round(tool, event, oe);
    	case PERF_RECORD_ID_INDEX:
    		return tool->id_index(session, event);
    	case PERF_RECORD_AUXTRACE_INFO:
    		return tool->auxtrace_info(session, event);
    	case PERF_RECORD_AUXTRACE:
    		/* setup for reading amidst mmap */
    		lseek(fd, file_offset + event->header.size, SEEK_SET);
    		return tool->auxtrace(session, event);
    	case PERF_RECORD_AUXTRACE_ERROR:
    		perf_session__auxtrace_error_inc(session, event);
    		return tool->auxtrace_error(session, event);
    	case PERF_RECORD_THREAD_MAP:
    		return tool->thread_map(session, event);
    	case PERF_RECORD_CPU_MAP:
    		return tool->cpu_map(session, event);
    	case PERF_RECORD_STAT_CONFIG:
    		return tool->stat_config(session, event);
    	case PERF_RECORD_STAT:
    		return tool->stat(session, event);
    	case PERF_RECORD_STAT_ROUND:
    		return tool->stat_round(session, event);
    	case PERF_RECORD_TIME_CONV:
    		session->time_conv = event->time_conv;
    		return tool->time_conv(session, event);
    	case PERF_RECORD_HEADER_FEATURE:
    		return tool->feature(session, event);
    	case PERF_RECORD_COMPRESSED:
    		err = tool->compressed(session, event, file_offset);
    		if (err)
    			dump_event(session->evlist, event, file_offset, &sample);
    		return err;
    	default:
    		return -EINVAL;
    	}
    }
    
    int perf_session__deliver_synth_event(struct perf_session *session,
    				      union perf_event *event,
    				      struct perf_sample *sample)
    {
    	struct evlist *evlist = session->evlist;
    	struct perf_tool *tool = session->tool;
    
    	events_stats__inc(&evlist->stats, event->header.type);
    
    	if (event->header.type >= PERF_RECORD_USER_TYPE_START)
    		return perf_session__process_user_event(session, event, 0);
    
    	return machines__deliver_event(&session->machines, evlist, event, sample, tool, 0);
    }
    
    static void event_swap(union perf_event *event, bool sample_id_all)
    {
    	perf_event__swap_op swap;
    
    	swap = perf_event__swap_ops[event->header.type];
    	if (swap)
    		swap(event, sample_id_all);
    }
    
    int perf_session__peek_event(struct perf_session *session, off_t file_offset,
    			     void *buf, size_t buf_sz,
    			     union perf_event **event_ptr,
    			     struct perf_sample *sample)
    {
    	union perf_event *event;
    	size_t hdr_sz, rest;
    	int fd;
    
    	if (session->one_mmap && !session->header.needs_swap) {
    		event = file_offset - session->one_mmap_offset +
    			session->one_mmap_addr;
    		goto out_parse_sample;
    	}
    
    	if (perf_data__is_pipe(session->data))
    		return -1;
    
    	fd = perf_data__fd(session->data);
    	hdr_sz = sizeof(struct perf_event_header);
    
    	if (buf_sz < hdr_sz)
    		return -1;
    
    	if (lseek(fd, file_offset, SEEK_SET) == (off_t)-1 ||
    	    readn(fd, buf, hdr_sz) != (ssize_t)hdr_sz)
    		return -1;
    
    	event = (union perf_event *)buf;
    
    	if (session->header.needs_swap)
    		perf_event_header__bswap(&event->header);
    
    	if (event->header.size < hdr_sz || event->header.size > buf_sz)
    		return -1;
    
    	rest = event->header.size - hdr_sz;
    
    	if (readn(fd, buf, rest) != (ssize_t)rest)
    		return -1;
    
    	if (session->header.needs_swap)
    		event_swap(event, evlist__sample_id_all(session->evlist));
    
    out_parse_sample:
    
    	if (sample && event->header.type < PERF_RECORD_USER_TYPE_START &&
    	    perf_evlist__parse_sample(session->evlist, event, sample))
    		return -1;
    
    	*event_ptr = event;
    
    	return 0;
    }
    
    int perf_session__peek_events(struct perf_session *session, u64 offset,
    			      u64 size, peek_events_cb_t cb, void *data)
    {
    	u64 max_offset = offset + size;
    	char buf[PERF_SAMPLE_MAX_SIZE];
    	union perf_event *event;
    	int err;
    
    	do {
    		err = perf_session__peek_event(session, offset, buf,
    					       PERF_SAMPLE_MAX_SIZE, &event,
    					       NULL);
    		if (err)
    			return err;
    
    		err = cb(session, event, offset, data);
    		if (err)
    			return err;
    
    		offset += event->header.size;
    		if (event->header.type == PERF_RECORD_AUXTRACE)
    			offset += event->auxtrace.size;
    
    	} while (offset < max_offset);
    
    	return err;
    }
    
    static s64 perf_session__process_event(struct perf_session *session,
    				       union perf_event *event, u64 file_offset)
    {
    	struct evlist *evlist = session->evlist;
    	struct perf_tool *tool = session->tool;
    	int ret;
    
    	if (session->header.needs_swap)
    		event_swap(event, evlist__sample_id_all(evlist));
    
    	if (event->header.type >= PERF_RECORD_HEADER_MAX)
    		return -EINVAL;
    
    	events_stats__inc(&evlist->stats, event->header.type);
    
    	if (event->header.type >= PERF_RECORD_USER_TYPE_START)
    		return perf_session__process_user_event(session, event, file_offset);
    
    	if (tool->ordered_events) {
    		u64 timestamp = -1ULL;
    
    		ret = perf_evlist__parse_sample_timestamp(evlist, event, &timestamp);
    		if (ret && ret != -1)
    			return ret;
    
    		ret = perf_session__queue_event(session, event, timestamp, file_offset);
    		if (ret != -ETIME)
    			return ret;
    	}
    
    	return perf_session__deliver_event(session, event, tool, file_offset);
    }
    
    void perf_event_header__bswap(struct perf_event_header *hdr)
    {
    	hdr->type = bswap_32(hdr->type);
    	hdr->misc = bswap_16(hdr->misc);
    	hdr->size = bswap_16(hdr->size);
    }
    
    struct thread *perf_session__findnew(struct perf_session *session, pid_t pid)
    {
    	return machine__findnew_thread(&session->machines.host, -1, pid);
    }
    
    /*
     * Threads are identified by pid and tid, and the idle task has pid == tid == 0.
     * So here a single thread is created for that, but actually there is a separate
     * idle task per cpu, so there should be one 'struct thread' per cpu, but there
     * is only 1. That causes problems for some tools, requiring workarounds. For
     * example get_idle_thread() in builtin-sched.c, or thread_stack__per_cpu().
     */
    int perf_session__register_idle_thread(struct perf_session *session)
    {
    	struct thread *thread;
    	int err = 0;
    
    	thread = machine__findnew_thread(&session->machines.host, 0, 0);
    	if (thread == NULL || thread__set_comm(thread, "swapper", 0)) {
    		pr_err("problem inserting idle task.\n");
    		err = -1;
    	}
    
    	if (thread == NULL || thread__set_namespaces(thread, 0, NULL)) {
    		pr_err("problem inserting idle task.\n");
    		err = -1;
    	}
    
    	/* machine__findnew_thread() got the thread, so put it */
    	thread__put(thread);
    	return err;
    }
    
    static void
    perf_session__warn_order(const struct perf_session *session)
    {
    	const struct ordered_events *oe = &session->ordered_events;
    	struct evsel *evsel;
    	bool should_warn = true;
    
    	evlist__for_each_entry(session->evlist, evsel) {
    		if (evsel->core.attr.write_backward)
    			should_warn = false;
    	}
    
    	if (!should_warn)
    		return;
    	if (oe->nr_unordered_events != 0)
    		ui__warning("%u out of order events recorded.\n", oe->nr_unordered_events);
    }
    
    static void perf_session__warn_about_errors(const struct perf_session *session)
    {
    	const struct events_stats *stats = &session->evlist->stats;
    
    	if (session->tool->lost == perf_event__process_lost &&
    	    stats->nr_events[PERF_RECORD_LOST] != 0) {
    		ui__warning("Processed %d events and lost %d chunks!\n\n"
    			    "Check IO/CPU overload!\n\n",
    			    stats->nr_events[0],
    			    stats->nr_events[PERF_RECORD_LOST]);
    	}
    
    	if (session->tool->lost_samples == perf_event__process_lost_samples) {
    		double drop_rate;
    
    		drop_rate = (double)stats->total_lost_samples /
    			    (double) (stats->nr_events[PERF_RECORD_SAMPLE] + stats->total_lost_samples);
    		if (drop_rate > 0.05) {
    			ui__warning("Processed %" PRIu64 " samples and lost %3.2f%%!\n\n",
    				    stats->nr_events[PERF_RECORD_SAMPLE] + stats->total_lost_samples,
    				    drop_rate * 100.0);
    		}
    	}
    
    	if (session->tool->aux == perf_event__process_aux &&
    	    stats->total_aux_lost != 0) {
    		ui__warning("AUX data lost %" PRIu64 " times out of %u!\n\n",
    			    stats->total_aux_lost,
    			    stats->nr_events[PERF_RECORD_AUX]);
    	}
    
    	if (session->tool->aux == perf_event__process_aux &&
    	    stats->total_aux_partial != 0) {
    		bool vmm_exclusive = false;
    
    		(void)sysfs__read_bool("module/kvm_intel/parameters/vmm_exclusive",
    		                       &vmm_exclusive);
    
    		ui__warning("AUX data had gaps in it %" PRIu64 " times out of %u!\n\n"
    		            "Are you running a KVM guest in the background?%s\n\n",
    			    stats->total_aux_partial,
    			    stats->nr_events[PERF_RECORD_AUX],
    			    vmm_exclusive ?
    			    "\nReloading kvm_intel module with vmm_exclusive=0\n"
    			    "will reduce the gaps to only guest's timeslices." :
    			    "");
    	}
    
    	if (stats->nr_unknown_events != 0) {
    		ui__warning("Found %u unknown events!\n\n"
    			    "Is this an older tool processing a perf.data "
    			    "file generated by a more recent tool?\n\n"
    			    "If that is not the case, consider "
    			    "reporting to linux-kernel@vger.kernel.org.\n\n",
    			    stats->nr_unknown_events);
    	}
    
    	if (stats->nr_unknown_id != 0) {
    		ui__warning("%u samples with id not present in the header\n",
    			    stats->nr_unknown_id);
    	}
    
    	if (stats->nr_invalid_chains != 0) {
    		ui__warning("Found invalid callchains!\n\n"
    			    "%u out of %u events were discarded for this reason.\n\n"
    			    "Consider reporting to linux-kernel@vger.kernel.org.\n\n",
    			    stats->nr_invalid_chains,
    			    stats->nr_events[PERF_RECORD_SAMPLE]);
    	}
    
    	if (stats->nr_unprocessable_samples != 0) {
    		ui__warning("%u unprocessable samples recorded.\n"
    			    "Do you have a KVM guest running and not using 'perf kvm'?\n",
    			    stats->nr_unprocessable_samples);
    	}
    
    	perf_session__warn_order(session);
    
    	events_stats__auxtrace_error_warn(stats);
    
    	if (stats->nr_proc_map_timeout != 0) {
    		ui__warning("%d map information files for pre-existing threads were\n"
    			    "not processed, if there are samples for addresses they\n"
    			    "will not be resolved, you may find out which are these\n"
    			    "threads by running with -v and redirecting the output\n"
    			    "to a file.\n"
    			    "The time limit to process proc map is too short?\n"
    			    "Increase it by --proc-map-timeout\n",
    			    stats->nr_proc_map_timeout);
    	}
    }
    
    static int perf_session__flush_thread_stack(struct thread *thread,
    					    void *p __maybe_unused)
    {
    	return thread_stack__flush(thread);
    }
    
    static int perf_session__flush_thread_stacks(struct perf_session *session)
    {
    	return machines__for_each_thread(&session->machines,
    					 perf_session__flush_thread_stack,
    					 NULL);
    }
    
    volatile int session_done;
    
    static int __perf_session__process_decomp_events(struct perf_session *session);
    
    static int __perf_session__process_pipe_events(struct perf_session *session)
    {
    	struct ordered_events *oe = &session->ordered_events;
    	struct perf_tool *tool = session->tool;
    	int fd = perf_data__fd(session->data);
    	union perf_event *event;
    	uint32_t size, cur_size = 0;
    	void *buf = NULL;
    	s64 skip = 0;
    	u64 head;
    	ssize_t err;
    	void *p;
    
    	perf_tool__fill_defaults(tool);
    
    	head = 0;
    	cur_size = sizeof(union perf_event);
    
    	buf = malloc(cur_size);
    	if (!buf)
    		return -errno;
    	ordered_events__set_copy_on_queue(oe, true);
    more:
    	event = buf;
    	err = readn(fd, event, sizeof(struct perf_event_header));
    	if (err <= 0) {
    		if (err == 0)
    			goto done;
    
    		pr_err("failed to read event header\n");
    		goto out_err;
    	}
    
    	if (session->header.needs_swap)
    		perf_event_header__bswap(&event->header);
    
    	size = event->header.size;
    	if (size < sizeof(struct perf_event_header)) {
    		pr_err("bad event header size\n");
    		goto out_err;
    	}
    
    	if (size > cur_size) {
    		void *new = realloc(buf, size);
    		if (!new) {
    			pr_err("failed to allocate memory to read event\n");
    			goto out_err;
    		}
    		buf = new;
    		cur_size = size;
    		event = buf;
    	}
    	p = event;
    	p += sizeof(struct perf_event_header);
    
    	if (size - sizeof(struct perf_event_header)) {
    		err = readn(fd, p, size - sizeof(struct perf_event_header));
    		if (err <= 0) {
    			if (err == 0) {
    				pr_err("unexpected end of event stream\n");
    				goto done;
    			}
    
    			pr_err("failed to read event data\n");
    			goto out_err;
    		}
    	}
    
    	if ((skip = perf_session__process_event(session, event, head)) < 0) {
    		pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
    		       head, event->header.size, event->header.type);
    		err = -EINVAL;
    		goto out_err;
    	}
    
    	head += size;
    
    	if (skip > 0)
    		head += skip;
    
    	err = __perf_session__process_decomp_events(session);
    	if (err)
    		goto out_err;
    
    	if (!session_done())
    		goto more;
    done:
    	/* do the final flush for ordered samples */
    	err = ordered_events__flush(oe, OE_FLUSH__FINAL);
    	if (err)
    		goto out_err;
    	err = auxtrace__flush_events(session, tool);
    	if (err)
    		goto out_err;
    	err = perf_session__flush_thread_stacks(session);
    out_err:
    	free(buf);
    	if (!tool->no_warn)
    		perf_session__warn_about_errors(session);
    	ordered_events__free(&session->ordered_events);
    	auxtrace__free_events(session);
    	return err;
    }
    
    static union perf_event *
    prefetch_event(char *buf, u64 head, size_t mmap_size,
    	       bool needs_swap, union perf_event *error)
    {
    	union perf_event *event;
    
    	/*
    	 * Ensure we have enough space remaining to read
    	 * the size of the event in the headers.
    	 */
    	if (head + sizeof(event->header) > mmap_size)
    		return NULL;
    
    	event = (union perf_event *)(buf + head);
    	if (needs_swap)
    		perf_event_header__bswap(&event->header);
    
    	if (head + event->header.size <= mmap_size)
    		return event;
    
    	/* We're not fetching the event so swap back again */
    	if (needs_swap)
    		perf_event_header__bswap(&event->header);
    
    	pr_debug("%s: head=%#" PRIx64 " event->header_size=%#x, mmap_size=%#zx:"
    		 " fuzzed or compressed perf.data?\n",__func__, head, event->header.size, mmap_size);
    
    	return error;
    }
    
    static union perf_event *
    fetch_mmaped_event(u64 head, size_t mmap_size, char *buf, bool needs_swap)
    {
    	return prefetch_event(buf, head, mmap_size, needs_swap, ERR_PTR(-EINVAL));
    }
    
    static union perf_event *
    fetch_decomp_event(u64 head, size_t mmap_size, char *buf, bool needs_swap)
    {
    	return prefetch_event(buf, head, mmap_size, needs_swap, NULL);
    }
    
    static int __perf_session__process_decomp_events(struct perf_session *session)
    {
    	s64 skip;
    	u64 size, file_pos = 0;
    	struct decomp *decomp = session->decomp_last;
    
    	if (!decomp)
    		return 0;
    
    	while (decomp->head < decomp->size && !session_done()) {
    		union perf_event *event = fetch_decomp_event(decomp->head, decomp->size, decomp->data,
    							     session->header.needs_swap);
    
    		if (!event)
    			break;
    
    		size = event->header.size;
    
    		if (size < sizeof(struct perf_event_header) ||
    		    (skip = perf_session__process_event(session, event, file_pos)) < 0) {
    			pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
    				decomp->file_pos + decomp->head, event->header.size, event->header.type);
    			return -EINVAL;
    		}
    
    		if (skip)
    			size += skip;
    
    		decomp->head += size;
    	}
    
    	return 0;
    }
    
    /*
     * On 64bit we can mmap the data file in one go. No need for tiny mmap
     * slices. On 32bit we use 32MB.
     */
    #if BITS_PER_LONG == 64
    #define MMAP_SIZE ULLONG_MAX
    #define NUM_MMAPS 1
    #else
    #define MMAP_SIZE (32 * 1024 * 1024ULL)
    #define NUM_MMAPS 128
    #endif
    
    struct reader;
    
    typedef s64 (*reader_cb_t)(struct perf_session *session,
    			   union perf_event *event,
    			   u64 file_offset);
    
    struct reader {
    	int		 fd;
    	u64		 data_size;
    	u64		 data_offset;
    	reader_cb_t	 process;
    };
    
    static int
    reader__process_events(struct reader *rd, struct perf_session *session,
    		       struct ui_progress *prog)
    {
    	u64 data_size = rd->data_size;
    	u64 head, page_offset, file_offset, file_pos, size;
    	int err = 0, mmap_prot, mmap_flags, map_idx = 0;
    	size_t	mmap_size;
    	char *buf, *mmaps[NUM_MMAPS];
    	union perf_event *event;
    	s64 skip;
    
    	page_offset = page_size * (rd->data_offset / page_size);
    	file_offset = page_offset;
    	head = rd->data_offset - page_offset;
    
    	ui_progress__init_size(prog, data_size, "Processing events...");
    
    	data_size += rd->data_offset;
    
    	mmap_size = MMAP_SIZE;
    	if (mmap_size > data_size) {
    		mmap_size = data_size;
    		session->one_mmap = true;
    	}
    
    	memset(mmaps, 0, sizeof(mmaps));
    
    	mmap_prot  = PROT_READ;
    	mmap_flags = MAP_SHARED;
    
    	if (session->header.needs_swap) {
    		mmap_prot  |= PROT_WRITE;
    		mmap_flags = MAP_PRIVATE;
    	}
    remap:
    	buf = mmap(NULL, mmap_size, mmap_prot, mmap_flags, rd->fd,
    		   file_offset);
    	if (buf == MAP_FAILED) {
    		pr_err("failed to mmap file\n");
    		err = -errno;
    		goto out;
    	}
    	mmaps[map_idx] = buf;
    	map_idx = (map_idx + 1) & (ARRAY_SIZE(mmaps) - 1);
    	file_pos = file_offset + head;
    	if (session->one_mmap) {
    		session->one_mmap_addr = buf;
    		session->one_mmap_offset = file_offset;
    	}
    
    more:
    	event = fetch_mmaped_event(head, mmap_size, buf, session->header.needs_swap);
    	if (IS_ERR(event))
    		return PTR_ERR(event);
    
    	if (!event) {
    		if (mmaps[map_idx]) {
    			munmap(mmaps[map_idx], mmap_size);
    			mmaps[map_idx] = NULL;
    		}
    
    		page_offset = page_size * (head / page_size);
    		file_offset += page_offset;
    		head -= page_offset;
    		goto remap;
    	}
    
    	size = event->header.size;
    
    	skip = -EINVAL;
    
    	if (size < sizeof(struct perf_event_header) ||
    	    (skip = rd->process(session, event, file_pos)) < 0) {
    		pr_err("%#" PRIx64 " [%#x]: failed to process type: %d [%s]\n",
    		       file_offset + head, event->header.size,
    		       event->header.type, strerror(-skip));
    		err = skip;
    		goto out;
    	}
    
    	if (skip)
    		size += skip;
    
    	head += size;
    	file_pos += size;
    
    	err = __perf_session__process_decomp_events(session);
    	if (err)
    		goto out;
    
    	ui_progress__update(prog, size);
    
    	if (session_done())
    		goto out;
    
    	if (file_pos < data_size)
    		goto more;
    
    out:
    	return err;
    }
    
    static s64 process_simple(struct perf_session *session,
    			  union perf_event *event,
    			  u64 file_offset)
    {
    	return perf_session__process_event(session, event, file_offset);
    }
    
    static int __perf_session__process_events(struct perf_session *session)
    {
    	struct reader rd = {
    		.fd		= perf_data__fd(session->data),
    		.data_size	= session->header.data_size,
    		.data_offset	= session->header.data_offset,
    		.process	= process_simple,
    	};
    	struct ordered_events *oe = &session->ordered_events;
    	struct perf_tool *tool = session->tool;
    	struct ui_progress prog;
    	int err;
    
    	perf_tool__fill_defaults(tool);
    
    	if (rd.data_size == 0)
    		return -1;
    
    	ui_progress__init_size(&prog, rd.data_size, "Processing events...");
    
    	err = reader__process_events(&rd, session, &prog);
    	if (err)
    		goto out_err;
    	/* do the final flush for ordered samples */
    	err = ordered_events__flush(oe, OE_FLUSH__FINAL);
    	if (err)
    		goto out_err;
    	err = auxtrace__flush_events(session, tool);
    	if (err)
    		goto out_err;
    	err = perf_session__flush_thread_stacks(session);
    out_err:
    	ui_progress__finish();
    	if (!tool->no_warn)
    		perf_session__warn_about_errors(session);
    	/*
    	 * We may switching perf.data output, make ordered_events
    	 * reusable.
    	 */
    	ordered_events__reinit(&session->ordered_events);
    	auxtrace__free_events(session);
    	session->one_mmap = false;
    	return err;
    }
    
    int perf_session__process_events(struct perf_session *session)
    {
    	if (perf_session__register_idle_thread(session) < 0)
    		return -ENOMEM;
    
    	if (perf_data__is_pipe(session->data))
    		return __perf_session__process_pipe_events(session);
    
    	return __perf_session__process_events(session);
    }
    
    bool perf_session__has_traces(struct perf_session *session, const char *msg)
    {
    	struct evsel *evsel;
    
    	evlist__for_each_entry(session->evlist, evsel) {
    		if (evsel->core.attr.type == PERF_TYPE_TRACEPOINT)
    			return true;
    	}
    
    	pr_err("No trace sample to read. Did you call 'perf %s'?\n", msg);
    	return false;
    }
    
    int map__set_kallsyms_ref_reloc_sym(struct map *map, const char *symbol_name, u64 addr)
    {
    	char *bracket;
    	struct ref_reloc_sym *ref;
    	struct kmap *kmap;
    
    	ref = zalloc(sizeof(struct ref_reloc_sym));
    	if (ref == NULL)
    		return -ENOMEM;
    
    	ref->name = strdup(symbol_name);
    	if (ref->name == NULL) {
    		free(ref);
    		return -ENOMEM;
    	}
    
    	bracket = strchr(ref->name, ']');
    	if (bracket)
    		*bracket = '\0';
    
    	ref->addr = addr;
    
    	kmap = map__kmap(map);
    	if (kmap)
    		kmap->ref_reloc_sym = ref;
    
    	return 0;
    }
    
    size_t perf_session__fprintf_dsos(struct perf_session *session, FILE *fp)
    {
    	return machines__fprintf_dsos(&session->machines, fp);
    }
    
    size_t perf_session__fprintf_dsos_buildid(struct perf_session *session, FILE *fp,
    					  bool (skip)(struct dso *dso, int parm), int parm)
    {
    	return machines__fprintf_dsos_buildid(&session->machines, fp, skip, parm);
    }
    
    size_t perf_session__fprintf_nr_events(struct perf_session *session, FILE *fp)
    {
    	size_t ret;
    	const char *msg = "";
    
    	if (perf_header__has_feat(&session->header, HEADER_AUXTRACE))
    		msg = " (excludes AUX area (e.g. instruction trace) decoded / synthesized events)";
    
    	ret = fprintf(fp, "\nAggregated stats:%s\n", msg);
    
    	ret += events_stats__fprintf(&session->evlist->stats, fp);
    	return ret;
    }
    
    size_t perf_session__fprintf(struct perf_session *session, FILE *fp)
    {
    	/*
    	 * FIXME: Here we have to actually print all the machines in this
    	 * session, not just the host...
    	 */
    	return machine__fprintf(&session->machines.host, fp);
    }
    
    struct evsel *perf_session__find_first_evtype(struct perf_session *session,
    					      unsigned int type)
    {
    	struct evsel *pos;
    
    	evlist__for_each_entry(session->evlist, pos) {
    		if (pos->core.attr.type == type)
    			return pos;
    	}
    	return NULL;
    }
    
    int perf_session__cpu_bitmap(struct perf_session *session,
    			     const char *cpu_list, unsigned long *cpu_bitmap)
    {
    	int i, err = -1;
    	struct perf_cpu_map *map;
    	int nr_cpus = min(session->header.env.nr_cpus_online, MAX_NR_CPUS);
    
    	for (i = 0; i < PERF_TYPE_MAX; ++i) {
    		struct evsel *evsel;
    
    		evsel = perf_session__find_first_evtype(session, i);
    		if (!evsel)
    			continue;
    
    		if (!(evsel->core.attr.sample_type & PERF_SAMPLE_CPU)) {
    			pr_err("File does not contain CPU events. "
    			       "Remove -C option to proceed.\n");
    			return -1;
    		}
    	}
    
    	map = perf_cpu_map__new(cpu_list);
    	if (map == NULL) {
    		pr_err("Invalid cpu_list\n");
    		return -1;
    	}
    
    	for (i = 0; i < map->nr; i++) {
    		int cpu = map->map[i];
    
    		if (cpu >= nr_cpus) {
    			pr_err("Requested CPU %d too large. "
    			       "Consider raising MAX_NR_CPUS\n", cpu);
    			goto out_delete_map;
    		}
    
    		set_bit(cpu, cpu_bitmap);
    	}
    
    	err = 0;
    
    out_delete_map:
    	perf_cpu_map__put(map);
    	return err;
    }
    
    void perf_session__fprintf_info(struct perf_session *session, FILE *fp,
    				bool full)
    {
    	if (session == NULL || fp == NULL)
    		return;
    
    	fprintf(fp, "# ========\n");
    	perf_header__fprintf_info(session, fp, full);
    	fprintf(fp, "# ========\n#\n");
    }
    
    int perf_event__process_id_index(struct perf_session *session,
    				 union perf_event *event)
    {
    	struct evlist *evlist = session->evlist;
    	struct perf_record_id_index *ie = &event->id_index;
    	size_t i, nr, max_nr;
    
    	max_nr = (ie->header.size - sizeof(struct perf_record_id_index)) /
    		 sizeof(struct id_index_entry);
    	nr = ie->nr;
    	if (nr > max_nr)
    		return -EINVAL;
    
    	if (dump_trace)
    		fprintf(stdout, " nr: %zu\n", nr);
    
    	for (i = 0; i < nr; i++) {
    		struct id_index_entry *e = &ie->entries[i];
    		struct perf_sample_id *sid;
    
    		if (dump_trace) {
    			fprintf(stdout,	" ... id: %"PRI_lu64, e->id);
    			fprintf(stdout,	"  idx: %"PRI_lu64, e->idx);
    			fprintf(stdout,	"  cpu: %"PRI_ld64, e->cpu);
    			fprintf(stdout,	"  tid: %"PRI_ld64"\n", e->tid);
    		}
    
    		sid = perf_evlist__id2sid(evlist, e->id);
    		if (!sid)
    			return -ENOENT;
    		sid->idx = e->idx;
    		sid->cpu = e->cpu;
    		sid->tid = e->tid;
    	}
    	return 0;
    }