• John Baldwin's avatar
    Decode kevent structures logged via ktrace(2) in kdump. · ffb66079
    John Baldwin authored
    - Add a new KTR_STRUCT_ARRAY ktrace record type which dumps an array of
      The structure name in the record payload is preceded by a size_t
      containing the size of the individual structures.  Use this to
      replace the previous code that dumped the kevent arrays dumped for
      kevent().  kdump is now able to decode the kevent structures rather
      than dumping their contents via a hexdump.
      One change from before is that the 'changes' and 'events' arrays are
      not marked with separate 'read' and 'write' annotations in kdump
      output.  Instead, the first array is the 'changes' array, and the
      second array (only present if kevent doesn't fail with an error) is
      the 'events' array.  For kevent(), empty arrays are denoted by an
      entry with an array containing zero entries rather than no record.
    - Move kevent decoding tables from truss to libsysdecode.
      This adds three new functions to decode members of struct kevent:
      sysdecode_kevent_filter, sysdecode_kevent_flags, and
      kdump uses these helper functions to pretty-print kevent fields.
    - Move structure definitions for freebsd11 and freebsd32 kevent
      structures to <sys/event.h> so that they can be shared with userland.
      The 32-bit structures are only exposed if _WANT_KEVENT32 is defined.
      The freebsd11 structures are only exposed if _WANT_FREEBSD11_KEVENT is
      defined.  The 32-bit freebsd11 structure requires both.
    - Decode freebsd11 kevent structures in truss for the compat11.kevent()
      system call.
    - Log 32-bit kevent structures via ktrace for 32-bit compat kevent()
      system calls.
    - While here, constify the 'void *data' argument to ktrstruct().
    Reviewed by:	kib (earlier version)
    MFC after:	1 month
    Differential Revision:	https://reviews.freebsd.org/D12470