diff options
| -rwxr-xr-x | tools/perf/pmu-events/jevents.py | 207 |
1 files changed, 162 insertions, 45 deletions
diff --git a/tools/perf/pmu-events/jevents.py b/tools/perf/pmu-events/jevents.py index 4b7948ba57d6..d722fcba2d9f 100755 --- a/tools/perf/pmu-events/jevents.py +++ b/tools/perf/pmu-events/jevents.py @@ -6,7 +6,8 @@ import csv import json import os import sys -from typing import (Callable, Optional, Sequence) +from typing import (Callable, Dict, Optional, Sequence, Set, Tuple) +import collections # Global command line arguments. _args = None @@ -20,6 +21,19 @@ _arch_std_events = {} _close_table = False # Events to write out when the table is closed _pending_events = [] +# Global BigCString shared by all structures. +_bcs = None +# Order specific JsonEvent attributes will be visited. +_json_event_attributes = [ + # cmp_sevent related attributes. + 'name', 'pmu', 'topic', 'desc', 'metric_name', 'metric_group', + # Seems useful, put it early. + 'event', + # Short things in alphabetical order. + 'aggr_mode', 'compat', 'deprecated', 'perpkg', 'unit', + # Longer things (the last won't be iterated over during decompress). + 'metric_constraint', 'metric_expr', 'long_desc' +] def removesuffix(s: str, suffix: str) -> str: @@ -39,6 +53,66 @@ def file_name_to_table_name(parents: Sequence[str], dirname: str) -> str: tblname += '_' + dirname return tblname.replace('-', '_') +def c_len(s: str) -> int: + """Return the length of s a C string + + This doesn't handle all escape characters properly. It first assumes + all \ are for escaping, it then adjusts as it will have over counted + \\. The code uses \000 rather than \0 as a terminator as an adjacent + number would be folded into a string of \0 (ie. "\0" + "5" doesn't + equal a terminator followed by the number 5 but the escape of + \05). The code adjusts for \000 but not properly for all octal, hex + or unicode values. + """ + try: + utf = s.encode(encoding='utf-8',errors='strict') + except: + print(f'broken string {s}') + raise + return len(utf) - utf.count(b'\\') + utf.count(b'\\\\') - (utf.count(b'\\000') * 2) + +class BigCString: + """A class to hold many strings concatenated together. + + Generating a large number of stand-alone C strings creates a large + number of relocations in position independent code. The BigCString + is a helper for this case. It builds a single string which within it + are all the other C strings (to avoid memory issues the string + itself is held as a list of strings). The offsets within the big + string are recorded and when stored to disk these don't need + relocation. + """ + strings: Set[str] + big_string: Sequence[str] + offsets: Dict[str, int] + + def __init__(self): + self.strings = set() + + def add(self, s: str) -> None: + """Called to add to the big string.""" + self.strings.add(s) + + def compute(self) -> None: + """Called once all strings are added to compute the string and offsets.""" + + # big_string_offset is the current location within the C string + # being appended to - comments, etc. don't count. big_string is + # the string contents represented as a list. Strings are immutable + # in Python and so appending to one causes memory issues, while + # lists are mutable. + big_string_offset = 0 + self.big_string = [] + self.offsets = {} + # Emit all strings in a sorted manner. + for s in sorted(self.strings): + self.offsets[s] = big_string_offset + self.big_string.append(f'/* offset={big_string_offset} */ "') + self.big_string.append(s) + self.big_string.append('"\n') + big_string_offset += c_len(s) + +_bcs = BigCString() class JsonEvent: """Representation of an event loaded from a json file dictionary.""" @@ -203,26 +277,18 @@ class JsonEvent: s += f'\t{attr} = {value},\n' return s + '}' + def build_c_string(self) -> str: + s = '' + for attr in _json_event_attributes: + x = getattr(self, attr) + s += f'{x}\\000' if x else '\\000' + return s + def to_c_string(self) -> str: """Representation of the event as a C struct initializer.""" - def attr_string(attr: str, value: str) -> str: - return f'\t.{attr} = \"{value}\",\n' - - def str_if_present(self, attr: str) -> str: - if not getattr(self, attr): - return '' - return attr_string(attr, getattr(self, attr)) - - s = '{\n' - for attr in [ - 'aggr_mode', 'compat', 'deprecated', 'desc', 'event', 'long_desc', - 'metric_constraint', 'metric_expr', 'metric_group', 'metric_name', - 'name', 'perpkg', 'pmu', 'topic', 'unit' - ]: - s += str_if_present(self, attr) - s += '},\n' - return s + s = self.build_c_string() + return f'{{ { _bcs.offsets[s] } }}, /* {s} */\n' def read_json_events(path: str, topic: str) -> Sequence[JsonEvent]: @@ -237,7 +303,6 @@ def read_json_events(path: str, topic: str) -> Sequence[JsonEvent]: event.topic = topic return result - def preprocess_arch_std_files(archpath: str) -> None: """Read in all architecture standard events.""" global _arch_std_events @@ -253,7 +318,7 @@ def print_events_table_prefix(tblname: str) -> None: global _close_table if _close_table: raise IOError('Printing table prefix but last table has no suffix') - _args.output_file.write(f'static const struct pmu_event {tblname}[] = {{\n') + _args.output_file.write(f'static const struct compact_pmu_event {tblname}[] = {{\n') _close_table = True @@ -268,13 +333,13 @@ def add_events_table_entries(item: os.DirEntry, topic: str) -> None: def print_events_table_suffix() -> None: """Optionally close events table.""" - def event_cmp_key(j: JsonEvent): - def fix_none(s: str): + def event_cmp_key(j: JsonEvent) -> Tuple[bool, str, str, str, str]: + def fix_none(s: Optional[str]) -> str: if s is None: return '' return s - return (not j.desc is None, fix_none(j.topic), fix_none(j.name), fix_none(j.pmu), + return (j.desc is not None, fix_none(j.topic), fix_none(j.name), fix_none(j.pmu), fix_none(j.metric_name)) global _close_table @@ -286,23 +351,37 @@ def print_events_table_suffix() -> None: _args.output_file.write(event.to_c_string()) _pending_events = [] - _args.output_file.write("""{ -\t.name = 0, -\t.event = 0, -\t.desc = 0, -}, -}; -""") + _args.output_file.write('};\n\n') _close_table = False +def get_topic(topic: str) -> str: + if topic.endswith('metrics.json'): + return 'metrics' + return removesuffix(topic, '.json').replace('-', ' ') + +def preprocess_one_file(parents: Sequence[str], item: os.DirEntry) -> None: + + if item.is_dir(): + return + + # base dir or too deep + level = len(parents) + if level == 0 or level > 4: + return + + # Ignore other directories. If the file name does not have a .json + # extension, ignore it. It could be a readme.txt for instance. + if not item.is_file() or not item.name.endswith('.json'): + return + + topic = get_topic(item.name) + for event in read_json_events(item.path, topic): + _bcs.add(event.build_c_string()) def process_one_file(parents: Sequence[str], item: os.DirEntry) -> None: """Process a JSON file during the main walk.""" global _sys_event_tables - def get_topic(topic: str) -> str: - return removesuffix(topic, '.json').replace('-', ' ') - def is_leaf_dir(path: str) -> bool: for item in os.scandir(path): if item.is_dir(): @@ -337,7 +416,8 @@ def print_mapping_table(archs: Sequence[str]) -> None: _args.output_file.write(""" /* Struct used to make the PMU event table implementation opaque to callers. */ struct pmu_events_table { - const struct pmu_event *entries; + const struct compact_pmu_event *entries; + size_t length; }; /* @@ -365,7 +445,10 @@ const struct pmu_events_map pmu_events_map[] = { _args.output_file.write("""{ \t.arch = "testarch", \t.cpuid = "testcpu", -\t.table = { pme_test_soc_cpu }, +\t.table = { +\t.entries = pme_test_soc_cpu, +\t.length = ARRAY_SIZE(pme_test_soc_cpu), +\t} }, """) else: @@ -380,7 +463,10 @@ const struct pmu_events_map pmu_events_map[] = { _args.output_file.write(f"""{{ \t.arch = "{arch}", \t.cpuid = "{cpuid}", -\t.table = {{ {tblname} }} +\t.table = {{ +\t\t.entries = {tblname}, +\t\t.length = ARRAY_SIZE({tblname}) +\t}} }}, """) first = False @@ -388,7 +474,7 @@ const struct pmu_events_map pmu_events_map[] = { _args.output_file.write("""{ \t.arch = 0, \t.cpuid = 0, -\t.table = { 0 }, +\t.table = { 0, 0 }, } }; """) @@ -406,23 +492,41 @@ static const struct pmu_sys_events pmu_sys_event_tables[] = { """) for tblname in _sys_event_tables: _args.output_file.write(f"""\t{{ -\t\t.table = {{ {tblname} }}, +\t\t.table = {{ +\t\t\t.entries = {tblname}, +\t\t\t.length = ARRAY_SIZE({tblname}) +\t\t}}, \t\t.name = \"{tblname}\", \t}}, """) _args.output_file.write("""\t{ -\t\t.table = { 0 } +\t\t.table = { 0, 0 } \t}, }; -int pmu_events_table_for_each_event(const struct pmu_events_table *table, pmu_event_iter_fn fn, +static void decompress(int offset, struct pmu_event *pe) +{ +\tconst char *p = &big_c_string[offset]; +""") + for attr in _json_event_attributes: + _args.output_file.write(f""" +\tpe->{attr} = (*p == '\\0' ? NULL : p); +""") + if attr == _json_event_attributes[-1]: + continue + _args.output_file.write('\twhile (*p++);') + _args.output_file.write("""} + +int pmu_events_table_for_each_event(const struct pmu_events_table *table, + pmu_event_iter_fn fn, void *data) { - for (const struct pmu_event *pe = &table->entries[0]; - pe->name || pe->metric_group || pe->metric_name; - pe++) { - int ret = fn(pe, table, data); + for (size_t i = 0; i < table->length; i++) { + struct pmu_event pe; + int ret; + decompress(table->entries[i].offset, &pe); + ret = fn(&pe, table, data); if (ret) return ret; } @@ -531,7 +635,7 @@ def main() -> None: help='Root of tree containing architecture directories containing json files' ) ap.add_argument( - 'output_file', type=argparse.FileType('w'), nargs='?', default=sys.stdout) + 'output_file', type=argparse.FileType('w', encoding='utf-8'), nargs='?', default=sys.stdout) _args = ap.parse_args() _args.output_file.write(""" @@ -541,6 +645,10 @@ def main() -> None: #include <string.h> #include <stddef.h> +struct compact_pmu_event { + int offset; +}; + """) archs = [] for item in os.scandir(_args.starting_dir): @@ -556,6 +664,15 @@ def main() -> None: for arch in archs: arch_path = f'{_args.starting_dir}/{arch}' preprocess_arch_std_files(arch_path) + ftw(arch_path, [], preprocess_one_file) + + _bcs.compute() + _args.output_file.write('static const char *const big_c_string =\n') + for s in _bcs.big_string: + _args.output_file.write(s) + _args.output_file.write(';\n\n') + for arch in archs: + arch_path = f'{_args.starting_dir}/{arch}' ftw(arch_path, [], process_one_file) print_events_table_suffix() |