Change Details

Important users of unr like tmpfs or pipes can get away with just ever-increasing counters, making the overhead of managing the state for 32 bit counters a pessimization. The code switches to an atomic variable. This can be further sped up by making the counts variable "allocate" ranges and store them per-cpu. To that end, the code mimics the 32-bit variant by having a struct. Architectures which failed to build with 64-bit atomics use a mutex-protected routine. tmpfs conversion will be done later.

Important users of unr like tmpfs or pipes can get away with just ever-increasing counters, making the overhead of managing the state for 32 bit counters a pessimization. The patch changes it to an atomic variable. This can be further sped up by making the counts variable "allocate" ranges and store them per-cpu. To that end, the code mimics the 32-bit variant by having a struct. Architectures which failed to build with 64-bit atomics use a mutex-protected routine. tmpfs conversion will be done later.

Important users of unr like tmpfs or pipes can get away with just ever-increasing counters, making the overhead of managing the state for 32 bit counters a pessimization. The code switchespatch changes it to an atomic variable. This can be further sped up by making the counts variable "allocate" ranges and store them per-cpu. To that end, the code mimics the 32-bit variant by having a struct. Architectures which failed to build with 64-bit atomics use a mutex-protected routine. tmpfs conversion will be done later.