Partners have requested the ability to configure more parts of Scudo
at runtime, notably the Secondary cache options (maximum number of
blocks cached, maximum size) as well as the TSD registry options
(the maximum number of TSDs in use).
This CL adds a few more Scudo specific mallopt parameters that are
passed down to the various subcomponents of the Combined allocator.
- M_CACHE_COUNT_MAX: sets the maximum number of Secondary cached items
- M_CACHE_SIZE_MAX: sets the maximum size of a cacheable item in the Secondary
- M_TSDS_COUNT_MAX: sets the maximum number of TSDs that can be used (Shared Registry only)
Regardinbg the TSDs maximum count, this is a one way option, only
allowing to increase the count.
In order to allow for this, I rearranged the code to have some setOption
member function to the relevant classes, using the scudo::Option class
enum to determine what is to be set.