Source code review around jump label usage

[SF Markus Elfring]

Hello,

I have tried another specific analysis out on the source files
of "Linux next-20151211" with help of the software "Coccinelle 1.0.4".
I have taken a more detailed look on the use of the goto statement
and corresponding jump labels.

Can statistics like the following support software evolution
and further constructive considerations?

âââââââââââââââââââââââââââââââââââââââââââââââââââââââ
â                 target                  â incidence â
âââââââââââââââââââââââââââââââââââââââââââââââââââââââ
â out                                     â      9782 â
â done                                    â      1344 â
â exit                                    â       950 â
â out_unlock                              â       538 â
â unlock                                  â       509 â
â bail                                    â       486 â
â error                                   â       418 â
â retry                                   â       414 â
â err                                     â       400 â
â end                                     â       332 â
â                 â                       â     â     â
â abts_pending                            â         1 â
â abts_err                                â         1 â
â absolute_address                        â         1 â
â abort2                                  â         1 â
â abort_fail                              â         1 â
â abort_end                               â         1 â
â abituguru_probe_error                   â         1 â
â abituguru_detect_no_pwms_exit           â         1 â
â abituguru_detect_bank1_sensor_type_exit â         1 â
âââââââââââââââââââââââââââââââââââââââââââââââââââââââ


How often are different jump targets used within function implementations?
(Functions without jump labels were not searched for this analysis approach.)

âââââââââââââââââââââââ
â counter â incidence â
âââââââââââââââââââââââ
â       1 â     18442 â
â       2 â      2002 â
â       3 â       356 â
â       4 â       106 â
â       5 â        31 â
â       6 â         7 â
â       7 â         2 â
â       8 â         3 â
âââââââââââââââââââââââ


How does the text length distribution look like for the used jump targets?

ââââââââââââââââââââââ
â length â incidence â
ââââââââââââââââââââââ
â      1 â         2 â
â      2 â        29 â
â      3 â     10640 â
â      4 â      3564 â
â      5 â      1714 â
â      6 â      1162 â
â      7 â      1245 â
â      8 â       881 â
â      9 â       787 â
â     10 â      1252 â
â   â    â     â     â
â     35 â         4 â
â     36 â         1 â
â     37 â         2 â
â     38 â         1 â
â     39 â         1 â
ââââââââââââââââââââââ


How often are jump targets called within specific function implementations?

ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
â         function         â          source file                    â line â      go to           â counter â
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
â do_ipv6_setsockopt       â net/ipv6/ipv6_sockglue.c                â  140 â e_inval              â      52 â
â dvb_register             â drivers/media/pci/cx88/cx88-dvb.c       â 1005 â frontend_detach      â      43 â
â dvb_init                 â drivers/media/pci/saa7134/saa7134-dvb.c â 1210 â detach_frontend      â      40 â
â gdbstub_single_step      â arch/mn10300/kernel/gdb-stub.c          â  491 â fault                â      38 â
â uinput_ioctl_handler     â drivers/input/misc/uinput.c             â  701 â out                  â      32 â
â         â                â               â                         â  â   â        â             â    â    â
â kvm_vm_compat_ioctl      â virt/kvm/kvm_main.c                     â 2916 â out                  â       1 â
â kvm_vm_ioctl             â virt/kvm/kvm_main.c                     â 2742 â out_free_irq_routing â       1 â
â kvm_vm_ioctl_create_vcpu â virt/kvm/kvm_main.c                     â 2257 â vcpu_destroy         â       1 â
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ


Do any of these numbers indicate update candidates which correspond to the
"one error jump label bug" symptom that is mentioned in the Linux coding
style documentation?

Regards,
Markus
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