On Wed, Jul 24, 2019 at 05:25:28PM +0100, Julien Grall wrote: > The function check_and_switch_context is used to: > 1) Check whether the ASID is still valid > 2) Generate a new one if it is not valid > 3) Switch the context > > While the latter is specific to the MM subsystem, the rest could be part > of the generic ASID allocator. > > After this patch, the function is now split in 3 parts which corresponds > to the use of the functions: > 1) asid_check_context: Check if the ASID is still valid > 2) asid_new_context: Generate a new ASID for the context > 3) check_and_switch_context: Call 1) and 2) and switch the context > > 1) and 2) have not been merged in a single function because we want to > avoid to add a branch in when the ASID is still valid. This will matter > when the code will be moved in separate file later on as 1) will reside > in the header as a static inline function. > > Signed-off-by: Julien Grall <julien.grall@xxxxxxx> > > --- > Will wants to avoid to add a branch when the ASID is still valid. So > 1) and 2) are in separates function. The former will move to a new > header and make static inline. Was this discussion logged somewhere, just to get the context? I presume by "branch" you meant the function call to asid_check_context(). Personally, I don't like the duplication of this function in patch 13. This is part of the ASID allocation algorithm and I prefer to keep them together (we even had a bug in here with the xchg use). Do you have any numbers to show how non-inlining this function affects the performance (hackbench -P would do). -- Catalin _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
