[RFC 4/8] hw/core: Add cache topology options in -smp

[Zhao Liu]

From: Zhao Liu <zhao1.liu@intel.com>

Add "l1d-cache", "l1i-cache". "l2-cache", and "l3-cache" options in
-smp to define the cache topology for SMP system.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
---
 hw/core/machine-smp.c | 128 ++++++++++++++++++++++++++++++++++++++++++
 hw/core/machine.c     |   4 ++
 qapi/machine.json     |  14 ++++-
 system/vl.c           |  15 +++++
 4 files changed, 160 insertions(+), 1 deletion(-)

diff --git a/hw/core/machine-smp.c b/hw/core/machine-smp.c
index 8a8296b0d05b..2cbd19f4aa57 100644
--- a/hw/core/machine-smp.c
+++ b/hw/core/machine-smp.c
@@ -61,6 +61,132 @@ static char *cpu_hierarchy_to_string(MachineState *ms)
     return g_string_free(s, false);
 }
 
+static bool machine_check_topo_support(MachineState *ms,
+                                       CPUTopoLevel topo)
+{
+    MachineClass *mc = MACHINE_GET_CLASS(ms);
+
+    if (topo == CPU_TOPO_LEVEL_MODULE && !mc->smp_props.modules_supported) {
+        return false;
+    }
+
+    if (topo == CPU_TOPO_LEVEL_CLUSTER && !mc->smp_props.clusters_supported) {
+        return false;
+    }
+
+    if (topo == CPU_TOPO_LEVEL_DIE && !mc->smp_props.dies_supported) {
+        return false;
+    }
+
+    if (topo == CPU_TOPO_LEVEL_BOOK && !mc->smp_props.books_supported) {
+        return false;
+    }
+
+    if (topo == CPU_TOPO_LEVEL_DRAWER && !mc->smp_props.drawers_supported) {
+        return false;
+    }
+
+    return true;
+}
+
+static int smp_cache_string_to_topology(MachineState *ms,
+                                        char *topo_str,
+                                        CPUTopoLevel *topo,
+                                        Error **errp)
+{
+    *topo = string_to_cpu_topo(topo_str);
+
+    if (*topo == CPU_TOPO_LEVEL_MAX || *topo == CPU_TOPO_LEVEL_INVALID) {
+        error_setg(errp, "Invalid cache topology level: %s. The cache "
+                   "topology should match the CPU topology level", topo_str);
+        return -1;
+    }
+
+    if (!machine_check_topo_support(ms, *topo)) {
+        error_setg(errp, "Invalid cache topology level: %s. The topology "
+                   "level is not supported by this machine", topo_str);
+        return -1;
+    }
+
+    return 0;
+}
+
+static void machine_parse_smp_cache_config(MachineState *ms,
+                                           const SMPConfiguration *config,
+                                           Error **errp)
+{
+    MachineClass *mc = MACHINE_GET_CLASS(ms);
+
+    if (config->l1d_cache) {
+        if (!mc->smp_props.l1_separated_cache_supported) {
+            error_setg(errp, "L1 D-cache topology not "
+                       "supported by this machine");
+            return;
+        }
+
+        if (smp_cache_string_to_topology(ms, config->l1d_cache,
+            &ms->smp_cache.l1d, errp)) {
+            return;
+        }
+    }
+
+    if (config->l1i_cache) {
+        if (!mc->smp_props.l1_separated_cache_supported) {
+            error_setg(errp, "L1 I-cache topology not "
+                       "supported by this machine");
+            return;
+        }
+
+        if (smp_cache_string_to_topology(ms, config->l1i_cache,
+            &ms->smp_cache.l1i, errp)) {
+            return;
+        }
+    }
+
+    if (config->l2_cache) {
+        if (!mc->smp_props.l2_unified_cache_supported) {
+            error_setg(errp, "L2 cache topology not "
+                       "supported by this machine");
+            return;
+        }
+
+        if (smp_cache_string_to_topology(ms, config->l2_cache,
+            &ms->smp_cache.l2, errp)) {
+            return;
+        }
+
+        if (ms->smp_cache.l1d > ms->smp_cache.l2 ||
+            ms->smp_cache.l1i > ms->smp_cache.l2) {
+            error_setg(errp, "Invalid L2 cache topology. "
+                       "L2 cache topology level should not be "
+                       "lower than L1 D-cache/L1 I-cache");
+            return;
+        }
+    }
+
+    if (config->l3_cache) {
+        if (!mc->smp_props.l2_unified_cache_supported) {
+            error_setg(errp, "L3 cache topology not "
+                       "supported by this machine");
+            return;
+        }
+
+        if (smp_cache_string_to_topology(ms, config->l3_cache,
+            &ms->smp_cache.l3, errp)) {
+            return;
+        }
+
+        if (ms->smp_cache.l1d > ms->smp_cache.l3 ||
+            ms->smp_cache.l1i > ms->smp_cache.l3 ||
+            ms->smp_cache.l2 > ms->smp_cache.l3) {
+            error_setg(errp, "Invalid L3 cache topology. "
+                       "L3 cache topology level should not be "
+                       "lower than L1 D-cache/L1 I-cache/L2 cache");
+            return;
+        }
+    }
+}
+
 /*
  * machine_parse_smp_config: Generic function used to parse the given
  *                           SMP configuration
@@ -249,6 +375,8 @@ void machine_parse_smp_config(MachineState *ms,
                    mc->name, mc->max_cpus);
         return;
     }
+
+    machine_parse_smp_cache_config(ms, config, errp);
 }
 
 unsigned int machine_topo_get_cores_per_socket(const MachineState *ms)
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 426f71770a84..cb5173927b0d 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -886,6 +886,10 @@ static void machine_get_smp(Object *obj, Visitor *v, const 
char *name,
         .has_cores = true, .cores = ms->smp.cores,
         .has_threads = true, .threads = ms->smp.threads,
         .has_maxcpus = true, .maxcpus = ms->smp.max_cpus,
+        .l1d_cache = g_strdup(cpu_topo_to_string(ms->smp_cache.l1d)),
+        .l1i_cache = g_strdup(cpu_topo_to_string(ms->smp_cache.l1i)),
+        .l2_cache = g_strdup(cpu_topo_to_string(ms->smp_cache.l2)),
+        .l3_cache = g_strdup(cpu_topo_to_string(ms->smp_cache.l3)),
     };
 
     if (!visit_type_SMPConfiguration(v, name, &config, &error_abort)) {
diff --git a/qapi/machine.json b/qapi/machine.json
index d0e7f1f615f3..0a923ac38803 100644
--- a/qapi/machine.json
+++ b/qapi/machine.json
@@ -1650,6 +1650,14 @@
 #
 # @threads: number of threads per core
 #
+# @l1d-cache: topology hierarchy of L1 data cache (since 9.0)
+#
+# @l1i-cache: topology hierarchy of L1 instruction cache (since 9.0)
+#
+# @l2-cache: topology hierarchy of L2 unified cache (since 9.0)
+#
+# @l3-cache: topology hierarchy of L3 unified cache (since 9.0)
+#
 # Since: 6.1
 ##
 { 'struct': 'SMPConfiguration', 'data': {
@@ -1662,7 +1670,11 @@
      '*modules': 'int',
      '*cores': 'int',
      '*threads': 'int',
-     '*maxcpus': 'int' } }
+     '*maxcpus': 'int',
+     '*l1d-cache': 'str',
+     '*l1i-cache': 'str',
+     '*l2-cache': 'str',
+     '*l3-cache': 'str' } }
 
 ##
 # @x-query-irq:
diff --git a/system/vl.c b/system/vl.c
index a82555ae1558..ac95e5ddb656 100644
--- a/system/vl.c
+++ b/system/vl.c
@@ -741,6 +741,9 @@ static QemuOptsList qemu_smp_opts = {
         }, {
             .name = "clusters",
             .type = QEMU_OPT_NUMBER,
+        }, {
+            .name = "modules",
+            .type = QEMU_OPT_NUMBER,
         }, {
             .name = "cores",
             .type = QEMU_OPT_NUMBER,
@@ -750,6 +753,18 @@ static QemuOptsList qemu_smp_opts = {
         }, {
             .name = "maxcpus",
             .type = QEMU_OPT_NUMBER,
+        }, {
+            .name = "l1d-cache",
+            .type = QEMU_OPT_STRING,
+        }, {
+            .name = "l1i-cache",
+            .type = QEMU_OPT_STRING,
+        }, {
+            .name = "l2-cache",
+            .type = QEMU_OPT_STRING,
+        }, {
+            .name = "l3-cache",
+            .type = QEMU_OPT_STRING,
         },
         { /*End of list */ }
     },
-- 
2.34.1