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> wrmsr(MSR_IA32_PQR_ASSOC, rmid, closid); > } > + > + if (static_branch_likely(&rdt_plza_enable_key)) { > + tmp = READ_ONCE(tsk->plza); > + if (tmp) > + plza = tmp; > + > + if (plza != state->cur_plza) { > + state->cur_plza = plza; > + wrmsr(MSR_IA32_PQR_PLZA_ASSOC, > + RMID_EN | state->plza_rmid, > + (plza ? PLZA_EN : 0) | CLOSID_EN | state->plza_closid); > + } > + } > + Babu, This addition to the context switch code surprised me. After your talk at LPC I had imagined that PLZA would be a single global setting so that every syscall/page-fault/interrupt would run with a different CLOSID (presumably one configured with more cache and memory bandwidth). But this patch series looks like things are more flexible with the ability to set different values (of RMID as well as CLOSID) per group. It looks like it is possible to have some resctrl group with very limited resources just bump up a bit when in ring0, while other groups may get some different amount. The additions for plza to the Documentation aren't helping me understand how users will apply this. Do you have some more examples? -Tony