tools: remove redundant Python event data structure definitions (iovi…

…sor#2204)

Simplify code following iovisor#2198 (iovisor#2198).

Some tools are not touched: mountsnoop.py, trace.py, lib/*.py, old/*.py.

tools/bashreadline.py

@@ -14,7 +14,6 @@
 from __future__ import print_function
 from bcc import BPF
 from time import strftime
-import ctypes as ct
 
 # load BPF program
 bpf_text = """
@@ -40,13 +39,6 @@
     return 0;
 };
 """
-STR_DATA = 80
-
-class Data(ct.Structure):
-    _fields_ = [
-        ("pid", ct.c_ulonglong),
-        ("str", ct.c_char * STR_DATA)
-    ]
 
 b = BPF(text=bpf_text)
 b.attach_uretprobe(name="/bin/bash", sym="readline", fn_name="printret")
@@ -55,7 +47,7 @@ class Data(ct.Structure):
 print("%-9s %-6s %s" % ("TIME", "PID", "COMMAND"))
 
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = b["events"].event(data)
     print("%-9s %-6d %s" % (strftime("%H:%M:%S"), event.pid,
                             event.str.decode('utf-8', 'replace')))
 

tools/biosnoop.py

@@ -15,7 +15,6 @@
 
 from __future__ import print_function
 from bcc import BPF
-import ctypes as ct
 import re
 
 # load BPF program
@@ -128,21 +127,6 @@
 b.attach_kprobe(event="blk_account_io_completion",
     fn_name="trace_req_completion")
 
-TASK_COMM_LEN = 16  # linux/sched.h
-DISK_NAME_LEN = 32  # linux/genhd.h
-
-class Data(ct.Structure):
-    _fields_ = [
-        ("pid", ct.c_ulonglong),
-        ("rwflag", ct.c_ulonglong),
-        ("delta", ct.c_ulonglong),
-        ("sector", ct.c_ulonglong),
-        ("len", ct.c_ulonglong),
-        ("ts", ct.c_ulonglong),
-        ("disk_name", ct.c_char * DISK_NAME_LEN),
-        ("name", ct.c_char * TASK_COMM_LEN)
-    ]
-
 # header
 print("%-14s %-14s %-6s %-7s %-2s %-9s %-7s %7s" % ("TIME(s)", "COMM", "PID",
     "DISK", "T", "SECTOR", "BYTES", "LAT(ms)"))
@@ -154,7 +138,7 @@ class Data(ct.Structure):
 
 # process event
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = b["events"].event(data)
 
     val = -1
     global start_ts

tools/btrfsslower.py

@@ -28,7 +28,6 @@
 from bcc import BPF
 import argparse
 from time import strftime
-import ctypes as ct
 
 # symbols
 kallsyms = "/proc/kallsyms"
@@ -287,24 +286,9 @@
     if args.ebpf:
         exit()
 
-# kernel->user event data: struct data_t
-DNAME_INLINE_LEN = 32   # linux/dcache.h
-TASK_COMM_LEN = 16      # linux/sched.h
-class Data(ct.Structure):
-    _fields_ = [
-        ("ts_us", ct.c_ulonglong),
-        ("type", ct.c_ulonglong),
-        ("size", ct.c_ulonglong),
-        ("offset", ct.c_ulonglong),
-        ("delta_us", ct.c_ulonglong),
-        ("pid", ct.c_ulonglong),
-        ("task", ct.c_char * TASK_COMM_LEN),
-        ("file", ct.c_char * DNAME_INLINE_LEN)
-    ]
-
 # process event
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = b["events"].event(data)
 
     type = 'R'
     if event.type == 1:

tools/capable.py

@@ -18,7 +18,6 @@
 import errno
 import argparse
 from time import strftime
-import ctypes as ct
 
 # arguments
 examples = """examples:
@@ -165,19 +164,6 @@ def __getattr__(self, name):
 # initialize BPF
 b = BPF(text=bpf_text)
 
-TASK_COMM_LEN = 16    # linux/sched.h
-
-class Data(ct.Structure):
-    _fields_ = [
-        ("tgid", ct.c_uint32),
-        ("pid", ct.c_uint32),
-        ("uid", ct.c_uint32),
-        ("cap", ct.c_int),
-        ("audit", ct.c_int),
-        ("comm", ct.c_char * TASK_COMM_LEN),
-    ] + ([("kernel_stack_id", ct.c_int)] if args.kernel_stack else []) \
-      + ([("user_stack_id", ct.c_int)] if args.user_stack else [])
-
 # header
 print("%-9s %-6s %-6s %-6s %-16s %-4s %-20s %s" % (
     "TIME", "UID", "PID", "TID", "COMM", "CAP", "NAME", "AUDIT"))
@@ -198,7 +184,7 @@ def print_stack(bpf, stack_id, stack_type, tgid):
 
 # process event
 def print_event(bpf, cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = b["events"].event(data)
 
     if event.cap in capabilities:
         name = capabilities[event.cap]

tools/cpuunclaimed.py

@@ -59,11 +59,9 @@
 from __future__ import print_function
 from bcc import BPF, PerfType, PerfSWConfig
 from time import sleep, strftime
-from ctypes import c_int
 import argparse
 import multiprocessing
 from os import getpid, system, open, close, dup, unlink, O_WRONLY
-import ctypes as ct
 from tempfile import NamedTemporaryFile
 
 # arguments
@@ -248,20 +246,14 @@ def check_runnable_weight_field():
 else:
     print(("Sampling run queues... Output every %s seconds. " +
           "Hit Ctrl-C to end.") % args.interval)
-class Data(ct.Structure):
-    _fields_ = [
-        ("ts", ct.c_ulonglong),
-        ("cpu", ct.c_ulonglong),
-        ("len", ct.c_ulonglong)
-    ]
 
 samples = {}
 group = {}
 last = 0
 
 # process event
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = b["events"].event(data)
     samples[event.ts] = {}
     samples[event.ts]['cpu'] = event.cpu
     samples[event.ts]['len'] = event.len

tools/criticalstat.py

@@ -15,7 +15,6 @@
 from __future__ import print_function
 from bcc import BPF
 import argparse
-import ctypes as ct
 import sys
 import subprocess
 import os.path
@@ -271,18 +270,6 @@
 
 b = BPF(text=bpf_text)
 
-TASK_COMM_LEN = 16    # linux/sched.h
-
-class Data(ct.Structure):
-    _fields_ = [
-        ("time", ct.c_ulonglong),
-        ("stack_id", ct.c_longlong),
-        ("cpu", ct.c_int),
-        ("id", ct.c_ulonglong),
-        ("addrs", ct.c_int * 4),
-        ("comm", ct.c_char * TASK_COMM_LEN),
-    ]
-
 def get_syms(kstack):
     syms = []
 
@@ -296,7 +283,7 @@ def get_syms(kstack):
 def print_event(cpu, data, size):
     try:
         global b
-        event = ct.cast(data, ct.POINTER(Data)).contents
+        event = b["events"].event(data)
         stack_traces = b['stack_traces']
         stext = b.ksymname('_stext')
 

tools/dbslower.py

@@ -27,7 +27,6 @@
 from bcc import BPF, USDT
 import argparse
 import re
-import ctypes as ct
 import subprocess
 
 examples = """examples:
@@ -203,18 +202,10 @@
     if args.ebpf:
         exit()
 
-class Data(ct.Structure):
-    _fields_ = [
-        ("pid", ct.c_ulonglong),
-        ("timestamp", ct.c_ulonglong),
-        ("delta", ct.c_ulonglong),
-        ("query", ct.c_char * 256)
-    ]
-
 start = BPF.monotonic_time()
 
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = bpf["events"].event(data)
     print("%-14.6f %-6d %8.3f %s" % (
         float(event.timestamp - start) / 1000000000,
         event.pid, float(event.delta) / 1000000, event.query))

tools/execsnoop.py

@@ -21,7 +21,6 @@
 from bcc.utils import ArgString, printb
 import bcc.utils as utils
 import argparse
-import ctypes as ct
 import re
 import time
 from collections import defaultdict
@@ -173,19 +172,6 @@
     print("%-8s" % ("TIME(s)"), end="")
 print("%-16s %-6s %-6s %3s %s" % ("PCOMM", "PID", "PPID", "RET", "ARGS"))
 
-TASK_COMM_LEN = 16      # linux/sched.h
-ARGSIZE = 128           # should match #define in C above
-
-class Data(ct.Structure):
-    _fields_ = [
-        ("pid", ct.c_uint),
-        ("ppid", ct.c_uint),
-        ("comm", ct.c_char * TASK_COMM_LEN),
-        ("type", ct.c_int),
-        ("argv", ct.c_char * ARGSIZE),
-        ("retval", ct.c_int),
-    ]
-
 class EventType(object):
     EVENT_ARG = 0
     EVENT_RET = 1
@@ -209,8 +195,7 @@ def get_ppid(pid):
 
 # process event
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
-
+    event = b["events"].event(data)
     skip = False
 
     if event.type == EventType.EVENT_ARG:

tools/ext4slower.py

@@ -29,7 +29,6 @@
 from bcc import BPF
 import argparse
 from time import strftime
-import ctypes as ct
 
 # symbols
 kallsyms = "/proc/kallsyms"
@@ -285,24 +284,9 @@
     if args.ebpf:
         exit()
 
-# kernel->user event data: struct data_t
-DNAME_INLINE_LEN = 32   # linux/dcache.h
-TASK_COMM_LEN = 16      # linux/sched.h
-class Data(ct.Structure):
-    _fields_ = [
-        ("ts_us", ct.c_ulonglong),
-        ("type", ct.c_ulonglong),
-        ("size", ct.c_ulonglong),
-        ("offset", ct.c_ulonglong),
-        ("delta_us", ct.c_ulonglong),
-        ("pid", ct.c_ulonglong),
-        ("task", ct.c_char * TASK_COMM_LEN),
-        ("file", ct.c_char * DNAME_INLINE_LEN)
-    ]
-
 # process event
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = b["events"].event(data)
 
     type = 'R'
     if event.type == 1:

tools/filelife.py

@@ -21,7 +21,6 @@
 from bcc import BPF
 import argparse
 from time import strftime
-import ctypes as ct
 
 # arguments
 examples = """examples:
@@ -100,17 +99,6 @@
 }
 """
 
-TASK_COMM_LEN = 16            # linux/sched.h
-DNAME_INLINE_LEN = 255        # linux/dcache.h
-
-class Data(ct.Structure):
-    _fields_ = [
-        ("pid", ct.c_uint),
-        ("delta", ct.c_ulonglong),
-        ("comm", ct.c_char * TASK_COMM_LEN),
-        ("fname", ct.c_char * DNAME_INLINE_LEN)
-    ]
-
 if args.pid:
     bpf_text = bpf_text.replace('FILTER',
         'if (pid != %s) { return 0; }' % args.pid)
@@ -134,7 +122,7 @@ class Data(ct.Structure):
 
 # process event
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = b["events"].event(data)
     print("%-8s %-6d %-16s %-7.2f %s" % (strftime("%H:%M:%S"), event.pid,
         event.comm.decode('utf-8', 'replace'), float(event.delta) / 1000,
         event.fname.decode('utf-8', 'replace')))

tools/fileslower.py

@@ -31,7 +31,6 @@
 from __future__ import print_function
 from bcc import BPF
 import argparse
-import ctypes as ct
 import time
 
 # arguments
@@ -210,20 +209,6 @@
     b.attach_kprobe(event="vfs_write", fn_name="trace_write_entry")
     b.attach_kretprobe(event="vfs_write", fn_name="trace_write_return")
 
-TASK_COMM_LEN = 16  # linux/sched.h
-DNAME_INLINE_LEN = 32  # linux/dcache.h
-
-class Data(ct.Structure):
-    _fields_ = [
-        ("mode", ct.c_int),
-        ("pid", ct.c_uint),
-        ("sz", ct.c_uint),
-        ("delta_us", ct.c_ulonglong),
-        ("name_len", ct.c_uint),
-        ("name", ct.c_char * DNAME_INLINE_LEN),
-        ("comm", ct.c_char * TASK_COMM_LEN),
-    ]
-
 mode_s = {
     0: 'R',
     1: 'W',
@@ -237,7 +222,7 @@ class Data(ct.Structure):
 start_ts = time.time()
 
 def print_event(cpu, data, size):
-    event = ct.cast(data, ct.POINTER(Data)).contents
+    event = b["events"].event(data)
 
     ms = float(event.delta_us) / 1000
     name = event.name.decode('utf-8', 'replace')