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>>>> >>>> - if (ctx->enable_cdpl2) >>>> + if (ctx->enable_cdpl2) { >>>> ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, true); >>>> + if (ret) >>>> + goto out_done; >>>> + } >>>> >>>> - if (!ret && ctx->enable_cdpl3) >>>> + if (ctx->enable_cdpl3) { >>>> ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, true); >>>> + if (ret) >>>> + goto out_cdpl2; >>>> + } >>>> >>>> - if (!ret && ctx->enable_mba_mbps) >>>> + if (ctx->enable_mba_mbps) { >>>> ret = set_mba_sc(true); >>>> + if (ret) >>>> + goto out_cdpl3; >>> >>> An error may be encountered here without CDP ever enabled or just >>> enabled for L2 or L3. I think that the error unwinding should >>> take care to not unwind an action that was not done. Considering >>> the information available I think checking either ctx->enable_... >>> or the checks used in rdt_disable_ctx() would be ok but for consistency >>> the resctrl_arch_get_cdp_enabled() checks may be most appropriate. >>> >>>> + } >>>> + >>>> + return 0; >>>> >>>> +out_cdpl3: >>> >>> So here I think there should be a check. >>> if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L3)) >>> >>>> + resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false); >>>> +out_cdpl2: >>> >>> ... and here a check: >>> if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2)) >> >> >> I know it does not hurt to add these checks. But, it may be unnecessary >> considering cdp_disable() has the check "if (r_hw->cdp_enabled)" already. >> Both are same checks. What do you think? > > Yes, good point. Thank you for checking. Considering this it looks like > rdt_disable_ctx() can be simplified also by removing those CDP > enabled checks from it? Also looks like rdt_disable_ctx()-> set_mba_sc(false) > can be called unconditionally. Yes. We can do that. -- Thanks Babu Moger