Hi Mike, After looking at this a little more, I think it would perhaps be better to define the real-mode function that causes IPI in book3s_hv_rm_xics.c along with other real-mode functions that operate on the xics.
Hope this is acceptable to you. If not, we can discuss when I re-submit the patch. Thanks. -suresh On 11/16/2015 03:34 PM, Suresh E. Warrier wrote: > Hi Mike, > > The changes you proposed look nicer than what I have here. > I will get that coded and tested and re=submit. > > Thanks. > -suresh > > On 11/15/2015 11:53 PM, Michael Ellerman wrote: >> Hi Suresh, >> >> On Thu, 2015-29-10 at 23:40:45 UTC, "Suresh E. Warrier" wrote: >>> This function supports IPI message passing for real >>> mode callers. >>> >>> diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c >>> index a53a130..8c07bfad 100644 >>> --- a/arch/powerpc/kernel/smp.c >>> +++ b/arch/powerpc/kernel/smp.c >>> @@ -235,6 +238,33 @@ void smp_muxed_ipi_message_pass(int cpu, int msg) >>> smp_ops->cause_ipi(cpu, info->data); >>> } >>> >>> +#if defined(CONFIG_KVM_XICS) && defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) >>> +/* >>> + * Message passing code for real mode callers. It does not use the >>> + * smp_ops->cause_ipi function to cause an IPI, because those functions >>> + * access the MFFR through an ioremapped address. >>> + */ >>> +void smp_muxed_ipi_rm_message_pass(int cpu, int msg) >>> +{ >>> + struct cpu_messages *info = &per_cpu(ipi_message, cpu); >>> + char *message = (char *)&info->messages; >>> + unsigned long xics_phys; >>> + >>> + /* >>> + * Order previous accesses before accesses in the IPI handler. >>> + */ >>> + smp_mb(); >>> + message[msg] = 1; >>> + >>> + /* >>> + * cause_ipi functions are required to include a full barrier >>> + * before doing whatever causes the IPI. >>> + */ >>> + xics_phys = paca[cpu].kvm_hstate.xics_phys; >>> + out_rm8((u8 *)(xics_phys + XICS_MFRR), IPI_PRIORITY); >>> +} >>> +#endif >> >> >> I'm not all that happy with this. This function does two things, one of which >> belongs in this file (setting message), and the other which definitely does >> not (the XICs part). >> >> I think the end result would be cleaner if we did something like: >> >> void smp_muxed_ipi_set_message(int cpu, int msg) >> { >> struct cpu_messages *info = &per_cpu(ipi_message, cpu); >> char *message = (char *)&info->messages; >> unsigned long xics_phys; >> >> /* >> * Order previous accesses before accesses in the IPI handler. >> */ >> smp_mb(); >> message[msg] = 1; >> } >> >> Which would be exported, and could also be used by >> smp_muxed_ipi_message_pass(). >> >> Then in icp_rm_set_vcpu_irq(), you would do something like: >> >> if (hcore != -1) { >> hcpu = hcore << threads_shift; >> kvmppc_host_rm_ops_hv->rm_core[hcore].rm_data = vcpu; >> smp_muxed_ipi_set_message(hcpu, PPC_MSG_RM_HOST_ACTION); >> icp_native_cause_ipi_real_mode(); >> } >> >> Where icp_native_cause_ipi_real_mode() is a new hook you define in >> icp_native.c >> which does the real mode write to MFRR. >> >> cheers >> _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev