<div dir="ltr">Hi,<div> </div><div>Thanks alot for all the reviews, I'm updating the codes, as for those headers,</div><div>hwcap.h is here: <a href="https://github.com/torvalds/linux/blob/v5.6/arch/arm/include/asm/hwcap.h">https://github.com/torvalds/linux/blob/v5.6/arch/arm/include/asm/hwcap.h</a> and should be available for 5.6,</div><div>auxv.h is from glibc: <a href="https://sourceware.org/git/?p=glibc.git;a=blob;f=misc/sys/auxv.h;h=1a563e1337e64e4218c1613b68dc2551a762ba00;hb=HEAD">https://sourceware.org/git/?p=glibc.git;a=blob;f=misc/sys/auxv.h;h=1a563e1337e64e4218c1613b68dc2551a762ba00;hb=HEAD</a></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">virCPUarmGetHost and the helpers it calls are architecture specific and should not be even compiled in on non-ARM. </blockquote><div> yeah, understandable, I just don't see other archs like ppc and s390 doing this so I didn't do it. </div><div> </div><div>BR,</div></div> <div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Apr 9, 2020 at 7:03 PM Jiri Denemark <<a href="mailto:jdenemar@redhat.com">jdenemar@redhat.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On Thu, Apr 02, 2020 at 17:03:59 +0800, Zhenyu Zheng wrote: > Introduce getHost support for ARM CPU driver, read > CPU vendor_id, part_id and flags from registers > directly. > > Signed-off-by: Zhenyu Zheng <<a href="mailto:zhengzhenyulixi@gmail.com" target="_blank">zhengzhenyulixi@gmail.com</a>> > --- > src/cpu/cpu_arm.c | 194 +++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 193 insertions(+), 1 deletion(-) In addition to all the coding style issues which Daniel pointed out... > diff --git a/src/cpu/cpu_arm.c b/src/cpu/cpu_arm.c > index 88b4d91946..c8f5ce7e8a 100644 > --- a/src/cpu/cpu_arm.c > +++ b/src/cpu/cpu_arm.c > @@ -21,6 +21,8 @@ > */ > > #include <config.h> > +#include <asm/hwcap.h> > +#include <sys/auxv.h> None of these header files exist on my system with linux 5.6 headers. > #include "viralloc.h" > #include "cpu.h" > @@ -31,6 +33,10 @@ > #include "virxml.h" > > #define VIR_FROM_THIS VIR_FROM_CPU > +/* Shift bit mask for parsing cpu flags */ > +#define BIT_SHIFTS(n) (1UL << (n)) > +/* The current max number of cpu flags on ARM is 32 */ > +#define MAX_CPU_FLAGS 32 > > VIR_LOG_INIT("cpu.cpu_arm"); > > @@ -498,14 +504,200 @@ virCPUarmValidateFeatures(virCPUDefPtr cpu) > return 0; > } > > +/** > + * armCpuDataFromRegs: > + * > + * @data: 64-bit arm CPU specific data > + * > + * Fetches CPU vendor_id and part_id from MIDR_EL1 register, parse CPU > + * flags from AT_HWCAP. There are currently 32 valid flags on ARM arch > + * represented by each bit. > + */ > +static int > +armCpuDataFromRegs(virCPUarmData *data) > +{ > + /* Generate human readable flag list according to the order of */ > + /* AT_HWCAP bit map */ > + const char *flag_list[MAX_CPU_FLAGS] = { > + "fp", "asimd", "evtstrm", "aes", "pmull", "sha1", "sha2", > + "crc32", "atomics", "fphp", "asimdhp", "cpuid", "asimdrdm", > + "jscvt", "fcma", "lrcpc", "dcpop", "sha3", "sm3", "sm4", > + "asimddp", "sha512", "sve", "asimdfhm", "dit", "uscat", > + "ilrcpc", "flagm", "ssbs", "sb", "paca", "pacg"}; I would expect these to be defined in src/cpu_map/arm_features.xml, although I'm not sure how well the new features would play with the existing ones... What do you think, Andrea? > + unsigned long cpuid, hwcaps; > + char **features = NULL; > + char *cpu_feature_str = NULL; > + int cpu_feature_index = 0; > + size_t i; > + > + if (!(getauxval(AT_HWCAP) & HWCAP_CPUID)) { > + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", > + _("CPUID registers unavailable")); > + return -1; > + } > + > + /* read the cpuid data from MIDR_EL1 register */ > + asm("mrs %0, MIDR_EL1" : "=r" (cpuid)); > + VIR_DEBUG("CPUID read from register: 0x%016lx", cpuid); > + > + /* parse the coresponding part_id bits */ > + data->pvr = cpuid>>4&0xFFF; > + /* parse the coresponding vendor_id bits */ > + data->vendor_id = cpuid>>24&0xFF; > + > + hwcaps = getauxval(AT_HWCAP); > + VIR_DEBUG("CPU flags read from register: 0x%016lx", hwcaps); > + > + if (VIR_ALLOC_N(features, MAX_CPU_FLAGS) < 0) > + return -1; > + > + /* shift bit map mask to parse for CPU flags */ > + for (i = 0; i< MAX_CPU_FLAGS; i++) { > + if (hwcaps & BIT_SHIFTS(i)) { > + features[cpu_feature_index] = g_strdup(flag_list[i]); > + cpu_feature_index++; > + } > + } > + > + if (cpu_feature_index > 1) { > + cpu_feature_str = virStringListJoin((const char **)features, " "); > + if (!cpu_feature_str) > + goto cleanup; > + } > + data->features = g_strdup(cpu_feature_str); > + > + return 0; > + > + cleanup: > + virStringListFree(features); > + VIR_FREE(cpu_feature_str); > + return -1; > +} > + > +static int > +armCpuDataParseFeatures(virCPUDefPtr cpu, > + const virCPUarmData *cpuData) > +{ > + int ret = -1; > + size_t i; > + char **features; > + > + if (!cpu || !cpuData) > + return ret; > + > + if (!(features = virStringSplitCount(cpuData->features, " ", > + 0, &cpu->nfeatures))) > + return ret; > + if (cpu->nfeatures) { > + if (VIR_ALLOC_N(cpu->features, cpu->nfeatures) < 0) > + goto error; > + > + for (i = 0; i < cpu->nfeatures; i++) { > + cpu->features[i].policy = VIR_CPU_FEATURE_REQUIRE; > + cpu->features[i].name = g_strdup(features[i]); > + } > + } > + > + ret = 0; > + > + cleanup: > + virStringListFree(features); > + return ret; > + > + error: > + for (i = 0; i < cpu->nfeatures; i++) > + VIR_FREE(cpu->features[i].name); > + VIR_FREE(cpu->features); > + cpu->nfeatures = 0; > + goto cleanup; > +} > + > +static int > +armDecode(virCPUDefPtr cpu, > + const virCPUarmData *cpuData, > + virDomainCapsCPUModelsPtr models) > +{ > + virCPUarmMapPtr map; > + virCPUarmModelPtr model; > + virCPUarmVendorPtr vendor = NULL; > + > + if (!cpuData || !(map = virCPUarmGetMap())) > + return -1; > + > + if (!(model = armModelFindByPVR(map, cpuData->pvr))) { > + virReportError(VIR_ERR_OPERATION_FAILED, > + _("Cannot find CPU model with PVR 0x%03lx"), > + cpuData->pvr); > + return -1; > + } > + > + if (!virCPUModelIsAllowed(model->name, models)) { > + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, > + _("CPU model %s is not supported by hypervisor"), > + model->name); > + return -1; > + } > + > + cpu->model = g_strdup(model->name); > + > + if (cpuData->vendor_id && > + !(vendor = armVendorFindByID(map, cpuData->vendor_id))) { > + virReportError(VIR_ERR_OPERATION_FAILED, > + _("Cannot find CPU vendor with vendor id 0x%02lx"), > + cpuData->vendor_id); > + return -1; > + } > + > + if (vendor) > + cpu->vendor = g_strdup(vendor->name); > + > + if (cpuData->features && > + armCpuDataParseFeatures(cpu, cpuData) < 0) > + return -1; > + > + return 0; > +} > + > +static int > +armDecodeCPUData(virCPUDefPtr cpu, > + const virCPUData *data, > + virDomainCapsCPUModelsPtr models) > +{ > + return armDecode(cpu, &data->data.arm, models); > +} > + > +static int > +virCPUarmGetHost(virCPUDefPtr cpu, > + virDomainCapsCPUModelsPtr models) > +{ > + virCPUDataPtr cpuData = NULL; > + int ret = -1; > + > + if (virCPUarmDriverInitialize() < 0) > + goto cleanup; > + > + if (!(cpuData = virCPUDataNew(archs[0]))) > + goto cleanup; > + > + if (armCpuDataFromRegs(&cpuData->data.arm) < 0) > + goto cleanup; > + > + ret = armDecodeCPUData(cpu, cpuData, models); > + > + cleanup: > + virCPUarmDataFree(cpuData); > + return ret; > +} virCPUarmGetHost and the helpers it calls are architecture specific and should not be even compiled in on non-ARM. Jirka </blockquote></div>