diff options
-rw-r--r-- | tools/perf/util/s390-cpumsf.c | 593 |
1 files changed, 585 insertions, 8 deletions
diff --git a/tools/perf/util/s390-cpumsf.c b/tools/perf/util/s390-cpumsf.c index 14728b0834c6..d2c78ffd9fee 100644 --- a/tools/perf/util/s390-cpumsf.c +++ b/tools/perf/util/s390-cpumsf.c @@ -4,6 +4,138 @@ * Auxtrace support for s390 CPU-Measurement Sampling Facility * * Author(s): Thomas Richter <tmricht@linux.ibm.com> + * + * Auxiliary traces are collected during 'perf record' using rbd000 event. + * Several PERF_RECORD_XXX are generated during recording: + * + * PERF_RECORD_AUX: + * Records that new data landed in the AUX buffer part. + * PERF_RECORD_AUXTRACE: + * Defines auxtrace data. Followed by the actual data. The contents of + * the auxtrace data is dependent on the event and the CPU. + * This record is generated by perf record command. For details + * see Documentation/perf.data-file-format.txt. + * PERF_RECORD_AUXTRACE_INFO: + * Defines a table of contains for PERF_RECORD_AUXTRACE records. This + * record is generated during 'perf record' command. Each record contains up + * to 256 entries describing offset and size of the AUXTRACE data in the + * perf.data file. + * PERF_RECORD_AUXTRACE_ERROR: + * Indicates an error during AUXTRACE collection such as buffer overflow. + * PERF_RECORD_FINISHED_ROUND: + * Perf events are not necessarily in time stamp order, as they can be + * collected in parallel on different CPUs. If the events should be + * processed in time order they need to be sorted first. + * Perf report guarantees that there is no reordering over a + * PERF_RECORD_FINISHED_ROUND boundary event. All perf records with a + * time stamp lower than this record are processed (and displayed) before + * the succeeding perf record are processed. + * + * These records are evaluated during perf report command. + * + * 1. PERF_RECORD_AUXTRACE_INFO is used to set up the infrastructure for + * auxiliary trace data processing. See s390_cpumsf_process_auxtrace_info() + * below. + * Auxiliary trace data is collected per CPU. To merge the data into the report + * an auxtrace_queue is created for each CPU. It is assumed that the auxtrace + * data is in ascending order. + * + * Each queue has a double linked list of auxtrace_buffers. This list contains + * the offset and size of a CPU's auxtrace data. During auxtrace processing + * the data portion is mmap()'ed. + * + * To sort the queues in chronological order, all queue access is controlled + * by the auxtrace_heap. This is basicly a stack, each stack element has two + * entries, the queue number and a time stamp. However the stack is sorted by + * the time stamps. The highest time stamp is at the bottom the lowest + * (nearest) time stamp is at the top. That sort order is maintained at all + * times! + * + * After the auxtrace infrastructure has been setup, the auxtrace queues are + * filled with data (offset/size pairs) and the auxtrace_heap is populated. + * + * 2. PERF_RECORD_XXX processing triggers access to the auxtrace_queues. + * Each record is handled by s390_cpumsf_process_event(). The time stamp of + * the perf record is compared with the time stamp located on the auxtrace_heap + * top element. If that time stamp is lower than the time stamp from the + * record sample, the auxtrace queues will be processed. As auxtrace queues + * control many auxtrace_buffers and each buffer can be quite large, the + * auxtrace buffer might be processed only partially. In this case the + * position in the auxtrace_buffer of that queue is remembered and the time + * stamp of the last processed entry of the auxtrace_buffer replaces the + * current auxtrace_heap top. + * + * 3. Auxtrace_queues might run of out data and are feeded by the + * PERF_RECORD_AUXTRACE handling, see s390_cpumsf_process_auxtrace_event(). + * + * Event Generation + * Each sampling-data entry in the auxilary trace data generates a perf sample. + * This sample is filled + * with data from the auxtrace such as PID/TID, instruction address, CPU state, + * etc. This sample is processed with perf_session__deliver_synth_event() to + * be included into the GUI. + * + * 4. PERF_RECORD_FINISHED_ROUND event is used to process all the remaining + * auxiliary traces entries until the time stamp of this record is reached + * auxtrace_heap top. This is triggered by ordered_event->deliver(). + * + * + * Perf event processing. + * Event processing of PERF_RECORD_XXX entries relies on time stamp entries. + * This is the function call sequence: + * + * __cmd_report() + * | + * perf_session__process_events() + * | + * __perf_session__process_events() + * | + * perf_session__process_event() + * | This functions splits the PERF_RECORD_XXX records. + * | - Those generated by perf record command (type number equal or higher + * | than PERF_RECORD_USER_TYPE_START) are handled by + * | perf_session__process_user_event(see below) + * | - Those generated by the kernel are handled by + * | perf_evlist__parse_sample_timestamp() + * | + * perf_evlist__parse_sample_timestamp() + * | Extract time stamp from sample data. + * | + * perf_session__queue_event() + * | If timestamp is positive the sample is entered into an ordered_event + * | list, sort order is the timestamp. The event processing is deferred until + * | later (see perf_session__process_user_event()). + * | Other timestamps (0 or -1) are handled immediately by + * | perf_session__deliver_event(). These are events generated at start up + * | of command perf record. They create PERF_RECORD_COMM and PERF_RECORD_MMAP* + * | records. They are needed to create a list of running processes and its + * | memory mappings and layout. They are needed at the beginning to enable + * | command perf report to create process trees and memory mappings. + * | + * perf_session__deliver_event() + * | Delivers a PERF_RECORD_XXX entry for handling. + * | + * auxtrace__process_event() + * | The timestamp of the PERF_RECORD_XXX entry is taken to correlate with + * | time stamps from the auxiliary trace buffers. This enables + * | synchronization between auxiliary trace data and the events on the + * | perf.data file. + * | + * machine__deliver_event() + * | Handles the PERF_RECORD_XXX event. This depends on the record type. + * It might update the process tree, update a process memory map or enter + * a sample with IP and call back chain data into GUI data pool. + * + * + * Deferred processing determined by perf_session__process_user_event() is + * finally processed when a PERF_RECORD_FINISHED_ROUND is encountered. These + * are generated during command perf record. + * The timestamp of PERF_RECORD_FINISHED_ROUND event is taken to process all + * PERF_RECORD_XXX entries stored in the ordered_event list. This list was + * built up while reading the perf.data file. + * Each event is now processed by calling perf_session__deliver_event(). + * This enables time synchronization between the data in the perf.data file and + * the data in the auxiliary trace buffers. */ #include <endian.h> @@ -37,6 +169,14 @@ struct s390_cpumsf { u32 auxtrace_type; u32 pmu_type; u16 machine_type; + bool data_queued; +}; + +struct s390_cpumsf_queue { + struct s390_cpumsf *sf; + unsigned int queue_nr; + struct auxtrace_buffer *buffer; + int cpu; }; /* Display s390 CPU measurement facility basic-sampling data entry */ @@ -181,8 +321,8 @@ static void s390_cpumsf_dump(struct s390_cpumsf *sf, const char *color = PERF_COLOR_BLUE; struct hws_basic_entry *basic; struct hws_diag_entry *diag; - size_t pos = 0; unsigned short bsdes, dsdes; + size_t pos = 0; color_fprintf(stdout, color, ". ... s390 AUX data: size %zu bytes\n", @@ -243,15 +383,414 @@ static void s390_cpumsf_dump_event(struct s390_cpumsf *sf, unsigned char *buf, s390_cpumsf_dump(sf, buf, len); } +#define S390_LPP_PID_MASK 0xffffffff + +static bool s390_cpumsf_make_event(size_t pos, + struct hws_basic_entry *basic, + struct s390_cpumsf_queue *sfq) +{ + struct perf_sample sample = { + .ip = basic->ia, + .pid = basic->hpp & S390_LPP_PID_MASK, + .tid = basic->hpp & S390_LPP_PID_MASK, + .cpumode = PERF_RECORD_MISC_CPUMODE_UNKNOWN, + .cpu = sfq->cpu, + .period = 1 + }; + union perf_event event; + + memset(&event, 0, sizeof(event)); + if (basic->CL == 1) /* Native LPAR mode */ + sample.cpumode = basic->P ? PERF_RECORD_MISC_USER + : PERF_RECORD_MISC_KERNEL; + else if (basic->CL == 2) /* Guest kernel/user space */ + sample.cpumode = basic->P ? PERF_RECORD_MISC_GUEST_USER + : PERF_RECORD_MISC_GUEST_KERNEL; + else if (basic->gpp || basic->prim_asn != 0xffff) + /* Use heuristics on old hardware */ + sample.cpumode = basic->P ? PERF_RECORD_MISC_GUEST_USER + : PERF_RECORD_MISC_GUEST_KERNEL; + else + sample.cpumode = basic->P ? PERF_RECORD_MISC_USER + : PERF_RECORD_MISC_KERNEL; + + event.sample.header.type = PERF_RECORD_SAMPLE; + event.sample.header.misc = sample.cpumode; + event.sample.header.size = sizeof(struct perf_event_header); + + pr_debug4("%s pos:%#zx ip:%#" PRIx64 " P:%d CL:%d pid:%d.%d cpumode:%d cpu:%d\n", + __func__, pos, sample.ip, basic->P, basic->CL, sample.pid, + sample.tid, sample.cpumode, sample.cpu); + if (perf_session__deliver_synth_event(sfq->sf->session, &event, + &sample)) { + pr_err("s390 Auxiliary Trace: failed to deliver event\n"); + return false; + } + return true; +} + +static unsigned long long get_trailer_time(const unsigned char *buf) +{ + struct hws_trailer_entry *te; + unsigned long long aux_time; + + te = (struct hws_trailer_entry *)(buf + S390_CPUMSF_PAGESZ + - sizeof(*te)); + + if (!te->clock_base) /* TOD_CLOCK_BASE value missing */ + return 0; + + /* Correct calculation to convert time stamp in trailer entry to + * nano seconds (taken from arch/s390 function tod_to_ns()). + * TOD_CLOCK_BASE is stored in trailer entry member progusage2. + */ + aux_time = trailer_timestamp(te) - te->progusage2; + aux_time = (aux_time >> 9) * 125 + (((aux_time & 0x1ff) * 125) >> 9); + return aux_time; +} + +/* Process the data samples of a single queue. The first parameter is a + * pointer to the queue, the second parameter is the time stamp. This + * is the time stamp: + * - of the event that triggered this processing. + * - or the time stamp when the last proccesing of this queue stopped. + * In this case it stopped at a 4KB page boundary and record the + * position on where to continue processing on the next invocation + * (see buffer->use_data and buffer->use_size). + * + * When this function returns the second parameter is updated to + * reflect the time stamp of the last processed auxiliary data entry + * (taken from the trailer entry of that page). The caller uses this + * returned time stamp to record the last processed entry in this + * queue. + * + * The function returns: + * 0: Processing successful. The second parameter returns the + * time stamp from the trailer entry until which position + * processing took place. Subsequent calls resume from this + * position. + * <0: An error occurred during processing. The second parameter + * returns the maximum time stamp. + * >0: Done on this queue. The second parameter returns the + * maximum time stamp. + */ +static int s390_cpumsf_samples(struct s390_cpumsf_queue *sfq, u64 *ts) +{ + struct s390_cpumsf *sf = sfq->sf; + unsigned char *buf = sfq->buffer->use_data; + size_t len = sfq->buffer->use_size; + struct hws_basic_entry *basic; + unsigned short bsdes, dsdes; + size_t pos = 0; + int err = 1; + u64 aux_ts; + + if (!s390_cpumsf_validate(sf->machine_type, buf, len, &bsdes, + &dsdes)) { + *ts = ~0ULL; + return -1; + } + + /* Get trailer entry time stamp and check if entries in + * this auxiliary page are ready for processing. If the + * time stamp of the first entry is too high, whole buffer + * can be skipped. In this case return time stamp. + */ + aux_ts = get_trailer_time(buf); + if (!aux_ts) { + pr_err("[%#08" PRIx64 "] Invalid AUX trailer entry TOD clock base\n", + sfq->buffer->data_offset); + aux_ts = ~0ULL; + goto out; + } + if (aux_ts > *ts) { + *ts = aux_ts; + return 0; + } + + while (pos < len) { + /* Handle Basic entry */ + basic = (struct hws_basic_entry *)(buf + pos); + if (s390_cpumsf_make_event(pos, basic, sfq)) + pos += bsdes; + else { + err = -EBADF; + goto out; + } + + pos += dsdes; /* Skip diagnositic entry */ + + /* Check for trailer entry */ + if (!s390_cpumsf_reached_trailer(bsdes + dsdes, pos)) { + pos = (pos + S390_CPUMSF_PAGESZ) + & ~(S390_CPUMSF_PAGESZ - 1); + /* Check existence of next page */ + if (pos >= len) + break; + aux_ts = get_trailer_time(buf + pos); + if (!aux_ts) { + aux_ts = ~0ULL; + goto out; + } + if (aux_ts > *ts) { + *ts = aux_ts; + sfq->buffer->use_data += pos; + sfq->buffer->use_size -= pos; + return 0; + } + } + } +out: + *ts = aux_ts; + sfq->buffer->use_size = 0; + sfq->buffer->use_data = NULL; + return err; /* Buffer completely scanned or error */ +} + +/* Run the s390 auxiliary trace decoder. + * Select the queue buffer to operate on, the caller already selected + * the proper queue, depending on second parameter 'ts'. + * This is the time stamp until which the auxiliary entries should + * be processed. This value is updated by called functions and + * returned to the caller. + * + * Resume processing in the current buffer. If there is no buffer + * get a new buffer from the queue and setup start position for + * processing. + * When a buffer is completely processed remove it from the queue + * before returning. + * + * This function returns + * 1: When the queue is empty. Second parameter will be set to + * maximum time stamp. + * 0: Normal processing done. + * <0: Error during queue buffer setup. This causes the caller + * to stop processing completely. + */ +static int s390_cpumsf_run_decoder(struct s390_cpumsf_queue *sfq, + u64 *ts) +{ + + struct auxtrace_buffer *buffer; + struct auxtrace_queue *queue; + int err; + + queue = &sfq->sf->queues.queue_array[sfq->queue_nr]; + + /* Get buffer and last position in buffer to resume + * decoding the auxiliary entries. One buffer might be large + * and decoding might stop in between. This depends on the time + * stamp of the trailer entry in each page of the auxiliary + * data and the time stamp of the event triggering the decoding. + */ + if (sfq->buffer == NULL) { + sfq->buffer = buffer = auxtrace_buffer__next(queue, + sfq->buffer); + if (!buffer) { + *ts = ~0ULL; + return 1; /* Processing done on this queue */ + } + /* Start with a new buffer on this queue */ + if (buffer->data) { + buffer->use_size = buffer->size; + buffer->use_data = buffer->data; + } + } else + buffer = sfq->buffer; + + if (!buffer->data) { + int fd = perf_data__fd(sfq->sf->session->data); + + buffer->data = auxtrace_buffer__get_data(buffer, fd); + if (!buffer->data) + return -ENOMEM; + buffer->use_size = buffer->size; + buffer->use_data = buffer->data; + } + pr_debug4("%s queue_nr:%d buffer:%" PRId64 " offset:%#" PRIx64 " size:%#zx rest:%#zx\n", + __func__, sfq->queue_nr, buffer->buffer_nr, buffer->offset, + buffer->size, buffer->use_size); + err = s390_cpumsf_samples(sfq, ts); + + /* If non-zero, there is either an error (err < 0) or the buffer is + * completely done (err > 0). The error is unrecoverable, usually + * some descriptors could not be read successfully, so continue with + * the next buffer. + * In both cases the parameter 'ts' has been updated. + */ + if (err) { + sfq->buffer = NULL; + list_del(&buffer->list); + auxtrace_buffer__free(buffer); + if (err > 0) /* Buffer done, no error */ + err = 0; + } + return err; +} + +static struct s390_cpumsf_queue * +s390_cpumsf_alloc_queue(struct s390_cpumsf *sf, unsigned int queue_nr) +{ + struct s390_cpumsf_queue *sfq; + + sfq = zalloc(sizeof(struct s390_cpumsf_queue)); + if (sfq == NULL) + return NULL; + + sfq->sf = sf; + sfq->queue_nr = queue_nr; + sfq->cpu = -1; + return sfq; +} + +static int s390_cpumsf_setup_queue(struct s390_cpumsf *sf, + struct auxtrace_queue *queue, + unsigned int queue_nr, u64 ts) +{ + struct s390_cpumsf_queue *sfq = queue->priv; + + if (list_empty(&queue->head)) + return 0; + + if (sfq == NULL) { + sfq = s390_cpumsf_alloc_queue(sf, queue_nr); + if (!sfq) + return -ENOMEM; + queue->priv = sfq; + + if (queue->cpu != -1) + sfq->cpu = queue->cpu; + } + return auxtrace_heap__add(&sf->heap, queue_nr, ts); +} + +static int s390_cpumsf_setup_queues(struct s390_cpumsf *sf, u64 ts) +{ + unsigned int i; + int ret = 0; + + for (i = 0; i < sf->queues.nr_queues; i++) { + ret = s390_cpumsf_setup_queue(sf, &sf->queues.queue_array[i], + i, ts); + if (ret) + break; + } + return ret; +} + +static int s390_cpumsf_update_queues(struct s390_cpumsf *sf, u64 ts) +{ + if (!sf->queues.new_data) + return 0; + + sf->queues.new_data = false; + return s390_cpumsf_setup_queues(sf, ts); +} + +static int s390_cpumsf_process_queues(struct s390_cpumsf *sf, u64 timestamp) +{ + unsigned int queue_nr; + u64 ts; + int ret; + + while (1) { + struct auxtrace_queue *queue; + struct s390_cpumsf_queue *sfq; + + if (!sf->heap.heap_cnt) + return 0; + + if (sf->heap.heap_array[0].ordinal >= timestamp) + return 0; + + queue_nr = sf->heap.heap_array[0].queue_nr; + queue = &sf->queues.queue_array[queue_nr]; + sfq = queue->priv; + + auxtrace_heap__pop(&sf->heap); + if (sf->heap.heap_cnt) { + ts = sf->heap.heap_array[0].ordinal + 1; + if (ts > timestamp) + ts = timestamp; + } else { + ts = timestamp; + } + + ret = s390_cpumsf_run_decoder(sfq, &ts); + if (ret < 0) { + auxtrace_heap__add(&sf->heap, queue_nr, ts); + return ret; + } + if (!ret) { + ret = auxtrace_heap__add(&sf->heap, queue_nr, ts); + if (ret < 0) + return ret; + } + } + return 0; +} + +static int s390_cpumsf_synth_error(struct s390_cpumsf *sf, int code, int cpu, + pid_t pid, pid_t tid, u64 ip) +{ + char msg[MAX_AUXTRACE_ERROR_MSG]; + union perf_event event; + int err; + + strncpy(msg, "Lost Auxiliary Trace Buffer", sizeof(msg) - 1); + auxtrace_synth_error(&event.auxtrace_error, PERF_AUXTRACE_ERROR_ITRACE, + code, cpu, pid, tid, ip, msg); + + err = perf_session__deliver_synth_event(sf->session, &event, NULL); + if (err) + pr_err("s390 Auxiliary Trace: failed to deliver error event," + "error %d\n", err); + return err; +} + +static int s390_cpumsf_lost(struct s390_cpumsf *sf, struct perf_sample *sample) +{ + return s390_cpumsf_synth_error(sf, 1, sample->cpu, + sample->pid, sample->tid, 0); +} + static int s390_cpumsf_process_event(struct perf_session *session __maybe_unused, - union perf_event *event __maybe_unused, - struct perf_sample *sample __maybe_unused, - struct perf_tool *tool __maybe_unused) + union perf_event *event, + struct perf_sample *sample, + struct perf_tool *tool) { - return 0; + struct s390_cpumsf *sf = container_of(session->auxtrace, + struct s390_cpumsf, + auxtrace); + u64 timestamp = sample->time; + int err = 0; + + if (dump_trace) + return 0; + + if (!tool->ordered_events) { + pr_err("s390 Auxiliary Trace requires ordered events\n"); + return -EINVAL; + } + + if (event->header.type == PERF_RECORD_AUX && + event->aux.flags & PERF_AUX_FLAG_TRUNCATED) + return s390_cpumsf_lost(sf, sample); + + if (timestamp) { + err = s390_cpumsf_update_queues(sf, timestamp); + if (!err) + err = s390_cpumsf_process_queues(sf, timestamp); + } + return err; } +struct s390_cpumsf_synth { + struct perf_tool cpumsf_tool; + struct perf_session *session; +}; + static int s390_cpumsf_process_auxtrace_event(struct perf_session *session, union perf_event *event __maybe_unused, @@ -266,6 +805,9 @@ s390_cpumsf_process_auxtrace_event(struct perf_session *session, off_t data_offset; int err; + if (sf->data_queued) + return 0; + if (perf_data__is_pipe(session->data)) { data_offset = 0; } else { @@ -290,17 +832,21 @@ s390_cpumsf_process_auxtrace_event(struct perf_session *session, return 0; } +static void s390_cpumsf_free_events(struct perf_session *session __maybe_unused) +{ +} + static int s390_cpumsf_flush(struct perf_session *session __maybe_unused, struct perf_tool *tool __maybe_unused) { return 0; } -static void s390_cpumsf_free_events(struct perf_session *session) +static void s390_cpumsf_free_queues(struct perf_session *session) { struct s390_cpumsf *sf = container_of(session->auxtrace, struct s390_cpumsf, - auxtrace); + auxtrace); struct auxtrace_queues *queues = &sf->queues; unsigned int i; @@ -316,7 +862,7 @@ static void s390_cpumsf_free(struct perf_session *session) auxtrace); auxtrace_heap__free(&sf->heap); - s390_cpumsf_free_events(session); + s390_cpumsf_free_queues(session); session->auxtrace = NULL; free(sf); } @@ -329,6 +875,19 @@ static int s390_cpumsf_get_type(const char *cpuid) return (ret == 1) ? family : 0; } +/* Check itrace options set on perf report command. + * Return true, if none are set or all options specified can be + * handled on s390. + * Return false otherwise. + */ +static bool check_auxtrace_itrace(struct itrace_synth_opts *itops) +{ + if (!itops || !itops->set) + return true; + pr_err("No --itrace options supported\n"); + return false; +} + int s390_cpumsf_process_auxtrace_info(union perf_event *event, struct perf_session *session) { @@ -343,6 +902,11 @@ int s390_cpumsf_process_auxtrace_info(union perf_event *event, if (sf == NULL) return -ENOMEM; + if (!check_auxtrace_itrace(session->itrace_synth_opts)) { + err = -EINVAL; + goto err_free; + } + err = auxtrace_queues__init(&sf->queues); if (err) goto err_free; @@ -360,8 +924,21 @@ int s390_cpumsf_process_auxtrace_info(union perf_event *event, sf->auxtrace.free = s390_cpumsf_free; session->auxtrace = &sf->auxtrace; + if (dump_trace) + return 0; + + err = auxtrace_queues__process_index(&sf->queues, session); + if (err) + goto err_free_queues; + + if (sf->queues.populated) + sf->data_queued = true; + return 0; +err_free_queues: + auxtrace_queues__free(&sf->queues); + session->auxtrace = NULL; err_free: free(sf); return err; |