arm64: context: Fix comments and remove pointless smp_wmb()

The comments in the ASID allocator incorrectly hint at an MP-style idiom
using the asid_generation and the active_asids array. In fact, the
synchronisation is achieved using a combination of an xchg operation
and a spinlock, so update the comments and remove the pointless smp_wmb().

Cc: James Morse <>
Signed-off-by: Will Deacon <>
1 file changed