> From: Ankit Agrawal <ankita@xxxxxxxxxx> > Sent: Thursday, February 8, 2024 3:13 PM > >> > + * Determine how many bytes to be actually read from the > >> > device memory. > >> > + * Read request beyond the actual device memory size is > >> > filled with ~0, > >> > + * while those beyond the actual reported size is skipped. > >> > + */ > >> > + if (offset >= memregion->memlength) > >> > + mem_count = 0; > >> > >> If mem_count == 0, going through nvgrace_gpu_map_and_read() is not > >> necessary. > > > > Harmless, other than the possibly unnecessary call through to > > nvgrace_gpu_map_device_mem(). Maybe both > nvgrace_gpu_map_and_read() > > and nvgrace_gpu_map_and_write() could conditionally return 0 as their > > first operation when !mem_count. Thanks, > > > >Alex > > IMO, this seems like adding too much code to reduce the call length for a > very specific case. If there aren't any strong opinion on this, I'm planning to > leave this code as it is. a slight difference. if mem_count==0 the result should always succeed no matter nvgrace_gpu_map_device_mem() succeeds or not. Of course if it fails it's already a big problem probably nobody cares about the subtle difference when reading non-exist range. but regarding to readability it's still clearer: if (mem_count) nvgrace_gpu_map_and_read();
