Messages in this thread Patch in this message | | | From | Adrian Hunter <> | Subject | [PATCH 2/3] perf tools: Add support for PERF_RECORD_TEXT_POKE | Date | Wed, 18 Dec 2019 16:26:17 +0200 |
| |
Add processing for PERF_RECORD_TEXT_POKE events. When a text poke event is processed, then the kernel dso data cache is updated with the poked bytes.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> --- tools/include/uapi/linux/perf_event.h | 19 +++++++++- tools/perf/builtin-record.c | 45 +++++++++++++++++++++++ tools/perf/lib/include/perf/event.h | 8 ++++ tools/perf/util/event.c | 39 ++++++++++++++++++++ tools/perf/util/event.h | 5 +++ tools/perf/util/evlist.h | 1 + tools/perf/util/machine.c | 34 +++++++++++++++++ tools/perf/util/machine.h | 3 ++ tools/perf/util/perf_event_attr_fprintf.c | 1 + tools/perf/util/record.c | 10 +++++ tools/perf/util/record.h | 1 + tools/perf/util/session.c | 20 ++++++++++ tools/perf/util/tool.h | 3 +- 13 files changed, 187 insertions(+), 2 deletions(-)
diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h index 377d794d3105..d8422ebf128c 100644 --- a/tools/include/uapi/linux/perf_event.h +++ b/tools/include/uapi/linux/perf_event.h @@ -377,7 +377,8 @@ struct perf_event_attr { ksymbol : 1, /* include ksymbol events */ bpf_event : 1, /* include bpf events */ aux_output : 1, /* generate AUX records instead of events */ - __reserved_1 : 32; + text_poke : 1, /* include text poke events */ + __reserved_1 : 31; union { __u32 wakeup_events; /* wakeup every n events */ @@ -1006,6 +1007,22 @@ enum perf_event_type { */ PERF_RECORD_BPF_EVENT = 18, + /* + * Records changes to kernel text i.e. self-modified code. + * 'len' is the number of old bytes, which is the same as the number + * of new bytes. 'bytes' contains the old bytes followed immediately + * by the new bytes. + * + * struct { + * struct perf_event_header header; + * u64 addr; + * u16 len; + * u8 bytes[]; + * struct sample_id sample_id; + * }; + */ + PERF_RECORD_TEXT_POKE = 19, + PERF_RECORD_MAX, /* non-ABI */ }; diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 4c301466101b..d56c3cbe97ae 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -723,6 +723,43 @@ static int record__auxtrace_init(struct record *rec __maybe_unused) #endif +static int record__config_text_poke(struct evlist *evlist) +{ + struct evsel *evsel; + int err; + + /* Nothing to do if text poke is already configured */ + evlist__for_each_entry(evlist, evsel) { + if (evsel->core.attr.text_poke) + return 0; + } + + err = parse_events(evlist, "dummy:u", NULL); + if (err) + return err; + + evsel = evlist__last(evlist); + + evsel->core.attr.freq = 0; + evsel->core.attr.sample_period = 1; + evsel->core.attr.text_poke = 1; + + evsel->core.system_wide = true; + evsel->no_aux_samples = true; + evsel->immediate = true; + + /* Text poke must be collected on all CPUs */ + perf_cpu_map__put(evsel->core.own_cpus); + evsel->core.own_cpus = perf_cpu_map__new(NULL); + perf_cpu_map__put(evsel->core.cpus); + evsel->core.cpus = perf_cpu_map__get(evsel->core.own_cpus); + + perf_evsel__set_sample_bit(evsel, TIME); + perf_evsel__reset_sample_bit(evsel, BRANCH_STACK); + + return 0; +} + static bool record__kcore_readable(struct machine *machine) { char kcore[PATH_MAX]; @@ -2610,6 +2647,14 @@ int cmd_record(int argc, const char **argv) if (rec->opts.full_auxtrace) rec->buildid_all = true; + if (rec->opts.text_poke) { + err = record__config_text_poke(rec->evlist); + if (err) { + pr_err("record__config_text_poke failed, error %d\n", err); + goto out; + } + } + if (record_opts__config(&rec->opts)) { err = -EINVAL; goto out; diff --git a/tools/perf/lib/include/perf/event.h b/tools/perf/lib/include/perf/event.h index 18106899cb4e..ecd2087e122e 100644 --- a/tools/perf/lib/include/perf/event.h +++ b/tools/perf/lib/include/perf/event.h @@ -105,6 +105,13 @@ struct perf_record_bpf_event { __u8 tag[BPF_TAG_SIZE]; // prog tag }; +struct perf_record_text_poke_event { + struct perf_event_header header; + __u64 addr; + __u16 len; + __u8 bytes[]; +}; + struct perf_record_sample { struct perf_event_header header; __u64 array[]; @@ -360,6 +367,7 @@ union perf_event { struct perf_record_sample sample; struct perf_record_bpf_event bpf; struct perf_record_ksymbol ksymbol; + struct perf_record_text_poke_event text_poke; struct perf_record_header_attr attr; struct perf_record_event_update event_update; struct perf_record_header_event_type event_type; diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c index c5447ff516a2..b0d934cdda31 100644 --- a/tools/perf/util/event.c +++ b/tools/perf/util/event.c @@ -31,6 +31,7 @@ #include "stat.h" #include "session.h" #include "bpf-event.h" +#include "print_binary.h" #include "tool.h" #include "../perf.h" @@ -54,6 +55,7 @@ static const char *perf_event__names[] = { [PERF_RECORD_NAMESPACES] = "NAMESPACES", [PERF_RECORD_KSYMBOL] = "KSYMBOL", [PERF_RECORD_BPF_EVENT] = "BPF_EVENT", + [PERF_RECORD_TEXT_POKE] = "TEXT_POKE", [PERF_RECORD_HEADER_ATTR] = "ATTR", [PERF_RECORD_HEADER_EVENT_TYPE] = "EVENT_TYPE", [PERF_RECORD_HEADER_TRACING_DATA] = "TRACING_DATA", @@ -252,6 +254,14 @@ int perf_event__process_bpf(struct perf_tool *tool __maybe_unused, return machine__process_bpf(machine, event, sample); } +int perf_event__process_text_poke(struct perf_tool *tool __maybe_unused, + union perf_event *event, + struct perf_sample *sample, + struct machine *machine) +{ + return machine__process_text_poke(machine, event, sample); +} + size_t perf_event__fprintf_mmap(union perf_event *event, FILE *fp) { return fprintf(fp, " %d/%d: [%#" PRI_lx64 "(%#" PRI_lx64 ") @ %#" PRI_lx64 "]: %c %s\n", @@ -398,6 +408,32 @@ size_t perf_event__fprintf_bpf(union perf_event *event, FILE *fp) event->bpf.type, event->bpf.flags, event->bpf.id); } +static int text_poke_printer(enum binary_printer_ops op, unsigned int val, + void *extra __maybe_unused, FILE *fp) +{ + if (op == BINARY_PRINT_NUM_DATA) + return fprintf(fp, " %02x", val); + if (op == BINARY_PRINT_LINE_END) + return fprintf(fp, "\n"); + return 0; +} + +size_t perf_event__fprintf_text_poke(union perf_event *event, FILE *fp) +{ + size_t ret = fprintf(fp, " addr %#" PRI_lx64 " len %u\n", + event->text_poke.addr, + event->text_poke.len); + + ret += fprintf(fp, " old bytes:"); + ret += binary__fprintf(event->text_poke.bytes, event->text_poke.len, 16, + text_poke_printer, NULL, fp); + ret += fprintf(fp, " new bytes:"); + ret += binary__fprintf(event->text_poke.bytes + event->text_poke.len, + event->text_poke.len, 16, text_poke_printer, + NULL, fp); + return ret; +} + size_t perf_event__fprintf(union perf_event *event, FILE *fp) { size_t ret = fprintf(fp, "PERF_RECORD_%s", @@ -439,6 +475,9 @@ size_t perf_event__fprintf(union perf_event *event, FILE *fp) case PERF_RECORD_BPF_EVENT: ret += perf_event__fprintf_bpf(event, fp); break; + case PERF_RECORD_TEXT_POKE: + ret += perf_event__fprintf_text_poke(event, fp); + break; default: ret += fprintf(fp, "\n"); } diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h index 85223159737c..cbe98e22527f 100644 --- a/tools/perf/util/event.h +++ b/tools/perf/util/event.h @@ -345,6 +345,10 @@ int perf_event__process_bpf(struct perf_tool *tool, union perf_event *event, struct perf_sample *sample, struct machine *machine); +int perf_event__process_text_poke(struct perf_tool *tool, + union perf_event *event, + struct perf_sample *sample, + struct machine *machine); int perf_event__process(struct perf_tool *tool, union perf_event *event, struct perf_sample *sample, @@ -378,6 +382,7 @@ size_t perf_event__fprintf_cpu_map(union perf_event *event, FILE *fp); size_t perf_event__fprintf_namespaces(union perf_event *event, FILE *fp); size_t perf_event__fprintf_ksymbol(union perf_event *event, FILE *fp); size_t perf_event__fprintf_bpf(union perf_event *event, FILE *fp); +size_t perf_event__fprintf_text_poke(union perf_event *event, FILE *fp); size_t perf_event__fprintf(union perf_event *event, FILE *fp); int kallsyms__get_function_start(const char *kallsyms_filename, diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h index f5bd5c386df1..93e9b35e53b0 100644 --- a/tools/perf/util/evlist.h +++ b/tools/perf/util/evlist.h @@ -175,6 +175,7 @@ struct callchain_param; void perf_evlist__set_id_pos(struct evlist *evlist); bool perf_can_sample_identifier(void); bool perf_can_record_switch_events(void); +bool perf_can_record_text_poke_events(void); bool perf_can_record_cpu_wide(void); bool perf_can_aux_sample(void); void perf_evlist__config(struct evlist *evlist, struct record_opts *opts, diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index c8c5410315e8..3449af7f6b81 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -770,6 +770,38 @@ int machine__process_ksymbol(struct machine *machine __maybe_unused, return machine__process_ksymbol_register(machine, event, sample); } +int machine__process_text_poke(struct machine *machine, union perf_event *event, + struct perf_sample *sample __maybe_unused) +{ + struct map *map = maps__find(&machine->kmaps, event->text_poke.addr); + + if (dump_trace) + perf_event__fprintf_text_poke(event, stdout); + + if (map) { + u8 *new_bytes = event->text_poke.bytes + event->text_poke.len; + int ret; + + /* + * Kernel maps might be changed when loading symbols so loading + * must be done prior to using kernel maps. + */ + map__load(map); + ret = dso__data_write_cache_addr(map->dso, map, machine, + event->text_poke.addr, + new_bytes, + event->text_poke.len); + if (ret != event->text_poke.len) + pr_err("Failed to write kernel text poke at %#" PRI_lx64 "\n", + event->text_poke.addr); + } else { + pr_err("Failed to find kernel text poke address map for %#" PRI_lx64 "\n", + event->text_poke.addr); + } + + return 0; +} + static struct map *machine__addnew_module_map(struct machine *machine, u64 start, const char *filename) { @@ -1901,6 +1933,8 @@ int machine__process_event(struct machine *machine, union perf_event *event, ret = machine__process_ksymbol(machine, event, sample); break; case PERF_RECORD_BPF_EVENT: ret = machine__process_bpf(machine, event, sample); break; + case PERF_RECORD_TEXT_POKE: + ret = machine__process_text_poke(machine, event, sample); break; default: ret = -1; break; diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h index be0a930eca89..0bb086acb7ed 100644 --- a/tools/perf/util/machine.h +++ b/tools/perf/util/machine.h @@ -135,6 +135,9 @@ int machine__process_mmap2_event(struct machine *machine, union perf_event *even int machine__process_ksymbol(struct machine *machine, union perf_event *event, struct perf_sample *sample); +int machine__process_text_poke(struct machine *machine, + union perf_event *event, + struct perf_sample *sample); int machine__process_event(struct machine *machine, union perf_event *event, struct perf_sample *sample); diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c index 651203126c71..4c6c700335a6 100644 --- a/tools/perf/util/perf_event_attr_fprintf.c +++ b/tools/perf/util/perf_event_attr_fprintf.c @@ -144,6 +144,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr, PRINT_ATTRf(aux_watermark, p_unsigned); PRINT_ATTRf(sample_max_stack, p_unsigned); PRINT_ATTRf(aux_sample_size, p_unsigned); + PRINT_ATTRf(text_poke, p_unsigned); return ret; } diff --git a/tools/perf/util/record.c b/tools/perf/util/record.c index 7def66168503..207ba2a65008 100644 --- a/tools/perf/util/record.c +++ b/tools/perf/util/record.c @@ -97,6 +97,11 @@ static void perf_probe_context_switch(struct evsel *evsel) evsel->core.attr.context_switch = 1; } +static void perf_probe_text_poke(struct evsel *evsel) +{ + evsel->core.attr.text_poke = 1; +} + bool perf_can_sample_identifier(void) { return perf_probe_api(perf_probe_sample_identifier); @@ -112,6 +117,11 @@ bool perf_can_record_switch_events(void) return perf_probe_api(perf_probe_context_switch); } +bool perf_can_record_text_poke_events(void) +{ + return perf_probe_api(perf_probe_text_poke); +} + bool perf_can_record_cpu_wide(void) { struct perf_event_attr attr = { diff --git a/tools/perf/util/record.h b/tools/perf/util/record.h index 5421fd2ad383..127b4ca11fd3 100644 --- a/tools/perf/util/record.h +++ b/tools/perf/util/record.h @@ -46,6 +46,7 @@ struct record_opts { bool sample_id; bool no_bpf_event; bool kcore; + bool text_poke; unsigned int freq; unsigned int mmap_pages; unsigned int auxtrace_mmap_pages; diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index d0d7d25b23e3..c0cd316d8e28 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -489,6 +489,8 @@ void perf_tool__fill_defaults(struct perf_tool *tool) 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) @@ -658,6 +660,21 @@ static void perf_event__switch_swap(union perf_event *event, bool 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.len = bswap_16(event->text_poke.len); + + if (sample_id_all) { + size_t len = sizeof(event->text_poke.len) + + event->text_poke.len * 2; + void *data = &event->text_poke.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) { @@ -931,6 +948,7 @@ static perf_event__swap_op perf_event__swap_ops[] = { [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, @@ -1470,6 +1488,8 @@ static int machines__deliver_event(struct machines *machines, 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; diff --git a/tools/perf/util/tool.h b/tools/perf/util/tool.h index 2abbf668b8de..006182923bbe 100644 --- a/tools/perf/util/tool.h +++ b/tools/perf/util/tool.h @@ -56,7 +56,8 @@ struct perf_tool { throttle, unthrottle, ksymbol, - bpf; + bpf, + text_poke; event_attr_op attr; event_attr_op event_update; -- 2.17.1
| |