diff options
Diffstat (limited to 'scripts/bpf_doc.py')
| -rwxr-xr-x | scripts/bpf_doc.py | 78 |
1 files changed, 71 insertions, 7 deletions
diff --git a/scripts/bpf_doc.py b/scripts/bpf_doc.py index dfb260de17a8..d5c389df6045 100755 --- a/scripts/bpf_doc.py +++ b/scripts/bpf_doc.py @@ -10,6 +10,9 @@ from __future__ import print_function import argparse import re import sys, os +import subprocess + +helpersDocStart = 'Start of BPF helper function descriptions:' class NoHelperFound(BaseException): pass @@ -47,6 +50,10 @@ class Helper(APIElement): @desc: textual description of the helper function @ret: description of the return value of the helper function """ + def __init__(self, *args, **kwargs): + super().__init__(*args, **kwargs) + self.enum_val = None + def proto_break_down(self): """ Break down helper function protocol into smaller chunks: return type, @@ -89,6 +96,7 @@ class HeaderParser(object): self.commands = [] self.desc_unique_helpers = set() self.define_unique_helpers = [] + self.helper_enum_vals = {} self.desc_syscalls = [] self.enum_syscalls = [] @@ -233,7 +241,7 @@ class HeaderParser(object): self.enum_syscalls = re.findall('(BPF\w+)+', bpf_cmd_str) def parse_desc_helpers(self): - self.seek_to('* Start of BPF helper function descriptions:', + self.seek_to(helpersDocStart, 'Could not find start of eBPF helper descriptions list') while True: try: @@ -245,30 +253,54 @@ class HeaderParser(object): break def parse_define_helpers(self): - # Parse the number of FN(...) in #define __BPF_FUNC_MAPPER to compare - # later with the number of unique function names present in description. + # Parse FN(...) in #define __BPF_FUNC_MAPPER to compare later with the + # number of unique function names present in description and use the + # correct enumeration value. # Note: seek_to(..) discards the first line below the target search text, # resulting in FN(unspec) being skipped and not added to self.define_unique_helpers. self.seek_to('#define __BPF_FUNC_MAPPER(FN)', 'Could not find start of eBPF helper definition list') - # Searches for either one or more FN(\w+) defines or a backslash for newline - p = re.compile('\s*(FN\(\w+\))+|\\\\') + # Searches for one FN(\w+) define or a backslash for newline + p = re.compile('\s*FN\((\w+)\)|\\\\') fn_defines_str = '' + i = 1 # 'unspec' is skipped as mentioned above while True: capture = p.match(self.line) if capture: fn_defines_str += self.line + self.helper_enum_vals[capture.expand(r'bpf_\1')] = i + i += 1 else: break self.line = self.reader.readline() # Find the number of occurences of FN(\w+) self.define_unique_helpers = re.findall('FN\(\w+\)', fn_defines_str) + def assign_helper_values(self): + seen_helpers = set() + for helper in self.helpers: + proto = helper.proto_break_down() + name = proto['name'] + try: + enum_val = self.helper_enum_vals[name] + except KeyError: + raise Exception("Helper %s is missing from enum bpf_func_id" % name) + + # Enforce current practice of having the descriptions ordered + # by enum value. + seen_helpers.add(name) + desc_val = len(seen_helpers) + if desc_val != enum_val: + raise Exception("Helper %s comment order (#%d) must be aligned with its position (#%d) in enum bpf_func_id" % (name, desc_val, enum_val)) + + helper.enum_val = enum_val + def run(self): self.parse_desc_syscall() self.parse_enum_syscall() self.parse_desc_helpers() self.parse_define_helpers() + self.assign_helper_values() self.reader.close() ############################################################################### @@ -357,6 +389,31 @@ class PrinterRST(Printer): print('') + def get_kernel_version(self): + try: + version = subprocess.run(['git', 'describe'], cwd=linuxRoot, + capture_output=True, check=True) + version = version.stdout.decode().rstrip() + except: + try: + version = subprocess.run(['make', 'kernelversion'], cwd=linuxRoot, + capture_output=True, check=True) + version = version.stdout.decode().rstrip() + except: + return 'Linux' + return 'Linux {version}'.format(version=version) + + def get_last_doc_update(self, delimiter): + try: + cmd = ['git', 'log', '-1', '--pretty=format:%cs', '--no-patch', + '-L', + '/{}/,/\*\//:include/uapi/linux/bpf.h'.format(delimiter)] + date = subprocess.run(cmd, cwd=linuxRoot, + capture_output=True, check=True) + return date.stdout.decode().rstrip() + except: + return '' + class PrinterHelpersRST(PrinterRST): """ A printer for dumping collected information about helpers as a ReStructured @@ -378,6 +435,8 @@ list of eBPF helper functions ------------------------------------------------------------------------------- :Manual section: 7 +:Version: {version} +{date_field}{date} DESCRIPTION =========== @@ -410,8 +469,13 @@ kernel at the top). HELPERS ======= ''' + kernelVersion = self.get_kernel_version() + lastUpdate = self.get_last_doc_update(helpersDocStart) + PrinterRST.print_license(self) - print(header) + print(header.format(version=kernelVersion, + date_field = ':Date: ' if lastUpdate else '', + date=lastUpdate)) def print_footer(self): footer = ''' @@ -761,7 +825,7 @@ class PrinterHelpers(Printer): comma = ', ' print(one_arg, end='') - print(') = (void *) %d;' % len(self.seen_helpers)) + print(') = (void *) %d;' % helper.enum_val) print('') ############################################################################### |