From 51290a9442c1b9347c43b2fec34b7aa979d26c77 Mon Sep 17 00:00:00 2001 Message-Id: <51290a9442c1b9347c43b2fec34b7aa979d26c77@dist-git> From: Jiri Denemark Date: Tue, 26 May 2020 10:59:34 +0200 Subject: [PATCH] cpu_x86: Add support for stepping part of CPU signature MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit CPU models defined in the cpu_map can use signature/@stepping attribute to match a limited set of stepping numbers. The value is a bitmap for bits 0..15 each corresponding to a single stepping value. For example, stepping='4-6,9' will match 4, 5, 6, and 9. Omitting the attribute is equivalent to stepping='0-15'. Signed-off-by: Jiri Denemark Reviewed-by: Ján Tomko (cherry picked from commit c7a27949954d78dc95459758e329fb9c580361bb) https://bugzilla.redhat.com/show_bug.cgi?id=1840010 Signed-off-by: Jiri Denemark Message-Id: <20bd9df72a22a004bb665409ddba20ff89a5b66d.1590483392.git.jdenemar@redhat.com> Reviewed-by: Ján Tomko --- src/cpu/cpu_x86.c | 60 +++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 50 insertions(+), 10 deletions(-) diff --git a/src/cpu/cpu_x86.c b/src/cpu/cpu_x86.c index 45a073c1d0..0d81f3d2ae 100644 --- a/src/cpu/cpu_x86.c +++ b/src/cpu/cpu_x86.c @@ -125,6 +125,7 @@ typedef struct _virCPUx86Signature virCPUx86Signature; struct _virCPUx86Signature { unsigned int family; unsigned int model; + virBitmapPtr stepping; }; typedef struct _virCPUx86Signatures virCPUx86Signatures; @@ -732,7 +733,17 @@ x86MakeSignature(unsigned int family, static uint32_t virCPUx86SignatureToCPUID(virCPUx86Signature *sig) { - return x86MakeSignature(sig->family, sig->model, 0); + unsigned int stepping = 0; + + if (sig->stepping) { + ssize_t firstBit; + + firstBit = virBitmapNextSetBit(sig->stepping, -1); + if (firstBit >= 0) + stepping = firstBit; + } + + return x86MakeSignature(sig->family, sig->model, stepping); } @@ -767,8 +778,8 @@ x86DataToSignatureFull(const virCPUx86Data *data, } -/* Mask out irrelevant bits (R and Step) from processor signature. */ -#define SIGNATURE_MASK 0x0fff3ff0 +/* Mask out reserved bits from processor signature. */ +#define SIGNATURE_MASK 0x0fff3fff static uint32_t x86DataToSignature(const virCPUx86Data *data) @@ -1134,9 +1145,14 @@ virCPUx86SignaturesNew(size_t count) static void virCPUx86SignaturesFree(virCPUx86SignaturesPtr sigs) { + size_t i; + if (!sigs) return; + for (i = 0; i < sigs->count; i++) + virBitmapFree(sigs->items[i].stepping); + g_free(sigs->items); g_free(sigs); } @@ -1153,8 +1169,12 @@ virCPUx86SignaturesCopy(virCPUx86SignaturesPtr src) dst = virCPUx86SignaturesNew(src->count); - for (i = 0; i < src->count; i++) - dst->items[i] = src->items[i]; + for (i = 0; i < src->count; i++) { + dst->items[i].family = src->items[i].family; + dst->items[i].model = src->items[i].model; + if (src->items[i].stepping) + dst->items[i].stepping = virBitmapNewCopy(src->items[i].stepping); + } return dst; } @@ -1176,7 +1196,9 @@ virCPUx86SignaturesMatch(virCPUx86SignaturesPtr sigs, for (i = 0; i < sigs->count; i++) { if (sigs->items[i].family == family && - sigs->items[i].model == model) + sigs->items[i].model == model && + (!sigs->items[i].stepping || + virBitmapIsBitSet(sigs->items[i].stepping, stepping))) return true; } @@ -1194,9 +1216,15 @@ virCPUx86SignaturesFormat(virCPUx86SignaturesPtr sigs) return virBufferContentAndReset(&buf); for (i = 0; i < sigs->count; i++) { - virBufferAsprintf(&buf, "(%u,%u,0), ", + g_autofree char *stepping = NULL; + + if (sigs->items[i].stepping) + stepping = virBitmapFormat(sigs->items[i].stepping); + + virBufferAsprintf(&buf, "(%u,%u,%s), ", sigs->items[i].family, - sigs->items[i].model); + sigs->items[i].model, + stepping ? stepping : "0-15"); } virBufferTrim(&buf, ", ", -1); @@ -1473,6 +1501,7 @@ x86ModelParseSignatures(virCPUx86ModelPtr model, for (i = 0; i < n; i++) { virCPUx86Signature *sig = &model->signatures->items[i]; + g_autofree char *stepping = NULL; int rc; ctxt->node = nodes[i]; @@ -1492,6 +1521,11 @@ x86ModelParseSignatures(virCPUx86ModelPtr model, model->name); return -1; } + + stepping = virXPathString("string(@stepping)", ctxt); + /* stepping corresponds to 4 bits in 32b signature, see above */ + if (stepping && virBitmapParse(stepping, &sig->stepping, 16) < 0) + return -1; } ctxt->node = root; @@ -2090,6 +2124,9 @@ x86Decode(virCPUDefPtr cpu, virDomainCapsCPUModelPtr hvModel = NULL; g_autofree char *sigs = NULL; uint32_t signature; + unsigned int sigFamily; + unsigned int sigModel; + unsigned int sigStepping; ssize_t i; int rc; @@ -2103,6 +2140,7 @@ x86Decode(virCPUDefPtr cpu, vendor = x86DataToVendor(&data, map); signature = x86DataToSignature(&data); + virCPUx86SignatureFromCPUID(signature, &sigFamily, &sigModel, &sigStepping); x86DataFilterTSX(&data, vendor, map); @@ -2184,8 +2222,10 @@ x86Decode(virCPUDefPtr cpu, sigs = virCPUx86SignaturesFormat(model->signatures); - VIR_DEBUG("Using CPU model %s (signatures %s) for CPU with signature %06lx", - model->name, NULLSTR(sigs), (unsigned long)signature); + VIR_DEBUG("Using CPU model %s with signatures [%s] for " + "CPU with signature (%u,%u,%u)", + model->name, NULLSTR(sigs), + sigFamily, sigModel, sigStepping); cpu->model = g_steal_pointer(&cpuModel->model); cpu->features = g_steal_pointer(&cpuModel->features); -- 2.26.2