On 09/24/2015 01:32 AM, Alvise Rigo wrote:
> + if (cpu == smp_cpus) {
> + if (smp_cpus >= EXCL_BITMAP_CELL_SZ) {
> + return bitmap[EXCL_BITMAP_GET_BYTE_OFFSET(addr)];
> + } else {
> + return bitmap[EXCL_BITMAP_GET_BYTE_OFFSET(addr)] &
> + ((1 << smp_cpus) - 1);
> + }
> + } else {
> + return bitmap[EXCL_BITMAP_GET_BYTE_OFFSET(addr)] & (1 <<
> EXCL_IDX(cpu));
> + }
How can more than one cpu have the same address exclusively?
Isn't this scheme giving a whole page to a cpu, not a cacheline?
That's going to cause ll/sc conflicts where real hardware wouldn't.
r~
