Update scripts to use increment (iovisor#1905)

* Replace boilerplate for increment with a call to `increment`

from new tooling. Found cases to replace using `ripgrep`[1]:
```
$ rg '\(\*\w+\)\s*\+\+' -l | grep tools | grep -v old
```

[1]: https://github.com/BurntSushi/ripgrep

* Replace boilerplate for bigger than 1 increments with the new
`increment` call

from new tooling. Found cases to replace using `ripgrep`[1]:
```
$ rg '\(\*\w+\)\s*\+=' -l | grep tools | grep -v old
```

[1]: https://github.com/BurntSushi/ripgrep

* Update examples indicating the alternative increment call for hash tables

docs/tutorial_bcc_python_developer.md

@@ -557,16 +557,19 @@ struct key_t {
 BPF_HASH(counts, struct key_t);
 
 int count(struct pt_regs *ctx) {
- if (!PT_REGS_PARM1(ctx))
- return 0;
+ if (!PT_REGS_PARM1(ctx))
+ return 0;
 
- struct key_t key = {};
- u64 zero = 0, *val;
+ struct key_t key = {};
+ u64 zero = 0, *val;
 
- bpf_probe_read(&key.c, sizeof(key.c), (void *)PT_REGS_PARM1(ctx));
- val = counts.lookup_or_init(&key, &zero);
- (*val)++;
- return 0;
+ bpf_probe_read(&key.c, sizeof(key.c), (void *)PT_REGS_PARM1(ctx));
+
+ // another possibility is using `counts.increment(key);`. It allows a second
+ // optional parameter to specify the increment step
+ val = counts.lookup_or_init(&key, &zero);
+ (*val)++;
+ return 0;
 };
 """)
 b.attach_uprobe(name="c", sym="strlen", fn_name="count")
@@ -681,6 +684,8 @@ int count_sched(struct pt_regs *ctx, struct task_struct *prev) {
  key.curr_pid = bpf_get_current_pid_tgid();
  key.prev_pid = prev->pid;
 
+ // another possibility is using `counts.increment(key);`. It allows a second
+ // optional parameter to specify the increment step
  val = stats.lookup_or_init(&key, &zero);
  (*val)++;
  return 0;

examples/tracing/mallocstacks.py

@@ -33,6 +33,7 @@
  if (key < 0)
  return 0;
 
+ // could also use `calls.increment(key, size);`
  u64 zero = 0, *val;
  val = calls.lookup_or_init(&key, &zero);
  (*val) += size;

examples/tracing/strlen_count.py

@@ -31,6 +31,7 @@
  u64 zero = 0, *val;
 
  bpf_probe_read(&key.c, sizeof(key.c), (void *)PT_REGS_PARM1(ctx));
+ // could also use `counts.increment(key)`
  val = counts.lookup_or_init(&key, &zero);
  (*val)++;
  return 0;

examples/tracing/task_switch.py

@@ -22,6 +22,7 @@
  key.curr_pid = bpf_get_current_pid_tgid();
  key.prev_pid = prev->pid;
 
+ // could also use `stats.increment(key);`
  val = stats.lookup_or_init(&key, &zero);
  (*val)++;
  return 0;

tools/cachestat.py

@@ -94,12 +94,10 @@ def usage():
 
 int do_count(struct pt_regs *ctx) {
  struct key_t key = {};
- u64 zero = 0, *val;
  u64 ip;
 
  key.ip = PT_REGS_IP(ctx);
- val = counts.lookup_or_init(&key, &zero); // update counter
- (*val)++;
+ counts.increment(key); // update counter
  return 0;
 }
 

tools/cachetop.py

@@ -153,7 +153,6 @@ def handle_loop(stdscr, args):
 
  int do_count(struct pt_regs *ctx) {
  struct key_t key = {};
- u64 zero = 0 , *val;
  u64 pid = bpf_get_current_pid_tgid();
  u32 uid = bpf_get_current_uid_gid();
 
@@ -162,8 +161,7 @@ def handle_loop(stdscr, args):
  key.uid = uid & 0xFFFFFFFF;
  bpf_get_current_comm(&(key.comm), 16);
 
- val = counts.lookup_or_init(&key, &zero); // update counter
- (*val)++;
+ counts.increment(key);
  return 0;
  }
 

tools/hardirqs.py

@@ -84,8 +84,7 @@
 
  irq_key_t key = {.slot = 0 /* ignore */};
  bpf_probe_read(&key.name, sizeof(key.name), name);
- u64 zero = 0, *vp = dist.lookup_or_init(&key, &zero);
- (*vp)++;
+ dist.increment(key);
 
  return 0;
 }
@@ -136,8 +135,7 @@
  bpf_text = bpf_text.replace('STORE',
  'irq_key_t key = {.slot = 0 /* ignore */};' +
  'bpf_probe_read(&key.name, sizeof(key.name), name);' +
- 'u64 zero = 0, *vp = dist.lookup_or_init(&key, &zero);' +
- '(*vp) += delta;')
+ 'dist.increment(key, delta);')
 if debug or args.ebpf:
  print(bpf_text)
  if args.ebpf:

tools/llcstat.py

@@ -58,9 +58,7 @@
  struct key_t key = {};
  get_key(&key);
 
- u64 zero = 0, *val;
- val = miss_count.lookup_or_init(&key, &zero);
- (*val) += ctx->sample_period;
+ miss_count.increment(key, ctx->sample_period);
 
  return 0;
 }
@@ -69,9 +67,7 @@
  struct key_t key = {};
  get_key(&key);
 
- u64 zero = 0, *val;
- val = ref_count.lookup_or_init(&key, &zero);
- (*val) += ctx->sample_period;
+ ref_count.increment(key, ctx->sample_period);
 
  return 0;
 }

tools/offcputime.py

@@ -156,7 +156,6 @@ def signal_ignore(signal, frame):
  }
 
  // create map key
- u64 zero = 0, *val;
  struct key_t key = {};
 
  key.pid = pid;
@@ -165,8 +164,7 @@ def signal_ignore(signal, frame):
  key.kernel_stack_id = KERNEL_STACK_GET;
  bpf_get_current_comm(&key.name, sizeof(key.name));
 
- val = counts.lookup_or_init(&key, &zero);
- (*val) += delta;
+ counts.increment(key, delta);
  return 0;
 }
 """

tools/offwaketime.py

@@ -193,7 +193,6 @@ def signal_ignore(signal, frame):
  }
 
  // create map key
- u64 zero = 0, *val;
  struct key_t key = {};
  struct wokeby_t *woke;
 
@@ -213,8 +212,7 @@ def signal_ignore(signal, frame):
  wokeby.delete(&pid);
  }
 
- val = counts.lookup_or_init(&key, &zero);
- (*val) += delta;
+ counts.increment(key, delta);
  return 0;
 }
 """
@@ -368,7 +366,7 @@ def signal_ignore(signal, frame):
 
  # print waker/wakee delimiter
  print(" %-16s %s" % ("--", "--"))
- 
+
  if not args.user_stacks_only:
  if stack_id_err(k.t_k_stack_id):
  print(" [Missed Kernel Stack]")

tools/profile.py

@@ -145,7 +145,6 @@ def stack_id_err(stack_id):
  return 0;
 
  // create map key
- u64 zero = 0, *val;
  struct key_t key = {.pid = pid};
  bpf_get_current_comm(&key.name, sizeof(key.name));
 
@@ -180,8 +179,7 @@ def stack_id_err(stack_id):
  }
  }
 
- val = counts.lookup_or_init(&key, &zero);
- (*val)++;
+ counts.increment(key);
  return 0;
 }
 """

tools/softirqs.py

@@ -110,8 +110,7 @@
 else:
  bpf_text = bpf_text.replace('STORE',
  'key.vec = valp->vec; ' +
- 'u64 zero = 0, *vp = dist.lookup_or_init(&key, &zero); ' +
- '(*vp) += delta;')
+ 'dist.increment(key, delta);')
 if debug or args.ebpf:
  print(bpf_text)
  if args.ebpf:

tools/stackcount.py

@@ -128,9 +128,7 @@ def load(self):
  key.tgid = GET_TGID;
  STORE_COMM
  %s
- u64 zero = 0;
- u64 *val = counts.lookup_or_init(&key, &zero);
- (*val)++;
+ counts.increment(key);
  return 0;
 }
  """

tools/tcpretrans.py

@@ -131,16 +131,16 @@
 }
 """
 
-struct_init = { 'ipv4': 
- { 'count' : 
+struct_init = { 'ipv4':
+ { 'count' :
  """
  struct ipv4_flow_key_t flow_key = {};
  flow_key.saddr = skp->__sk_common.skc_rcv_saddr;
  flow_key.daddr = skp->__sk_common.skc_daddr;
  // lport is host order
  flow_key.lport = lport;
  flow_key.dport = ntohs(dport);""",
- 'trace' : 
+ 'trace' :
  """
  struct ipv4_data_t data4 = {.pid = pid, .ip = 4, .type = type};
  data4.saddr = skp->__sk_common.skc_rcv_saddr;
@@ -150,7 +150,7 @@
  data4.dport = ntohs(dport);
  data4.state = state; """
  },
- 'ipv6': 
+ 'ipv6':
  { 'count' :
  """
  struct ipv6_flow_key_t flow_key = {};
@@ -175,10 +175,8 @@
  }
 
 count_core_base = """
- u64 zero = 0, *val;
- val = COUNT_STRUCT.lookup_or_init(&flow_key, &zero);
- (*val)++;
-""" 
+ COUNT_STRUCT.increment(flow_key);
+"""
 
 if args.count:
  bpf_text = bpf_text.replace("IPV4_INIT", struct_init['ipv4']['count'])
@@ -266,7 +264,7 @@ def depict_cnt(counts_tab, l3prot='ipv4'):
  ep_fmt = "[%s]#%d"
  if l3prot == 'ipv4':
  depict_key = "%-20s <-> %-20s" % (ep_fmt % (inet_ntop(AF_INET, pack('I', k.saddr)), k.lport),
- ep_fmt % (inet_ntop(AF_INET, pack('I', k.daddr)), k.dport)) 
+ ep_fmt % (inet_ntop(AF_INET, pack('I', k.daddr)), k.dport))
  else:
  depict_key = "%-20s <-> %-20s" % (ep_fmt % (inet_ntop(AF_INET6, k.saddr), k.lport),
  ep_fmt % (inet_ntop(AF_INET6, k.daddr), k.dport))
@@ -290,7 +288,7 @@ def depict_cnt(counts_tab, l3prot='ipv4'):
  # header
  print("\n%-25s %-25s %-10s" % (
  "LADDR:LPORT", "RADDR:RPORT", "RETRANSMITS"))
- depict_cnt(b.get_table("ipv4_count")) 
+ depict_cnt(b.get_table("ipv4_count"))
  depict_cnt(b.get_table("ipv6_count"), l3prot='ipv6')
 # read events
 else:

tools/tcpsubnet.py

@@ -114,7 +114,6 @@
  struct msghdr *msg, size_t size)
 {
  u16 family = sk->__sk_common.skc_family;
- u64 *val, zero = 0;
 
  if (family == AF_INET) {
  u32 dst = sk->__sk_common.skc_daddr;
@@ -176,9 +175,8 @@ def generate_bpf_subnets(subnets):
  if (!categorized && (__NET_ADDR__ & __NET_MASK__) ==
  (dst & __NET_MASK__)) {
  struct index_key_t key = {.index = __POS__};
- val = ipv4_send_bytes.lookup_or_init(&key, &zero);
+ ipv4_send_bytes.increment(key, size);
  categorized = 1;
- (*val) += size;
  }
  """
  bpf = ''

tools/tcptop.py

@@ -104,7 +104,6 @@ def range_check(string):
  u32 pid = bpf_get_current_pid_tgid();
  FILTER
  u16 dport = 0, family = sk->__sk_common.skc_family;
- u64 *val, zero = 0;
 
  if (family == AF_INET) {
  struct ipv4_key_t ipv4_key = {.pid = pid};
@@ -113,8 +112,7 @@ def range_check(string):
  ipv4_key.lport = sk->__sk_common.skc_num;
  dport = sk->__sk_common.skc_dport;
  ipv4_key.dport = ntohs(dport);
- val = ipv4_send_bytes.lookup_or_init(&ipv4_key, &zero);
- (*val) += size;
+ ipv4_send_bytes.increment(ipv4_key, size);
 
  } else if (family == AF_INET6) {
  struct ipv6_key_t ipv6_key = {.pid = pid};
@@ -126,8 +124,8 @@ def range_check(string):
  ipv6_key.lport = sk->__sk_common.skc_num;
  dport = sk->__sk_common.skc_dport;
  ipv6_key.dport = ntohs(dport);
- val = ipv6_send_bytes.lookup_or_init(&ipv6_key, &zero);
- (*val) += size;
+ ipv6_send_bytes.increment(ipv6_key, size);
+
  }
  // else drop
 
@@ -157,8 +155,8 @@ def range_check(string):
  ipv4_key.lport = sk->__sk_common.skc_num;
  dport = sk->__sk_common.skc_dport;
  ipv4_key.dport = ntohs(dport);
- val = ipv4_recv_bytes.lookup_or_init(&ipv4_key, &zero);
- (*val) += copied;
+ ipv4_recv_bytes.increment(ipv4_key, copied);
+
 
  } else if (family == AF_INET6) {
  struct ipv6_key_t ipv6_key = {.pid = pid};
@@ -169,8 +167,7 @@ def range_check(string):
  ipv6_key.lport = sk->__sk_common.skc_num;
  dport = sk->__sk_common.skc_dport;
  ipv6_key.dport = ntohs(dport);
- val = ipv6_recv_bytes.lookup_or_init(&ipv6_key, &zero);
- (*val) += copied;
+ ipv6_recv_bytes.increment(ipv6_key, copied);
  }
  // else drop
 

tools/vfscount.py

@@ -27,10 +27,8 @@
 
 int do_count(struct pt_regs *ctx) {
  struct key_t key = {};
- u64 zero = 0, *val;
  key.ip = PT_REGS_IP(ctx);
- val = counts.lookup_or_init(&key, &zero);
- (*val)++;
+ counts.increment(key);
  return 0;
 }
 """)

tools/wakeuptime.py

@@ -134,14 +134,12 @@ def signal_ignore(signal, frame):
  return 0;
 
  struct key_t key = {};
- u64 zero = 0, *val;
 
  key.w_k_stack_id = stack_traces.get_stackid(ctx, BPF_F_REUSE_STACKID);
  bpf_probe_read(&key.target, sizeof(key.target), p->comm);
  bpf_get_current_comm(&key.waker, sizeof(key.waker));
 
- val = counts.lookup_or_init(&key, &zero);
- (*val) += delta;
+ counts.increment(key, delta);
  return 0;
 }
 """