[PATCH v9 4/7] i386: Clean up cache CPUID code

Babu Moger
2018-05-14T16:41:53Z

From: Eduardo Habkost <ehabkost@redhat.com>

Always initialize CPUCaches structs with cache information, even
if legacy_cache=true. Use different CPUCaches struct for
CPUID[2], CPUID[4], and the AMD CPUID leaves.

This will simplify a lot the logic inside cpu_x86_cpuid().

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
---
target/i386/cpu.c | 145 +++++++++++++++++++++-------------------------
target/i386/cpu.h | 14 +++--
2 files changed, 75 insertions(+), 84 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 7f40241786..c06a9f5ebe 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1156,7 +1156,7 @@ struct X86CPUDefinition {
};

static CPUCaches epyc_cache_info = {
- .l1d_cache = {
+ .l1d_cache = &(CPUCacheInfo) {
.type = DCACHE,
.level = 1,
.size = 32 * KiB,
@@ -1168,7 +1168,7 @@ static CPUCaches epyc_cache_info = {
.self_init = 1,
.no_invd_sharing = true,
},
- .l1i_cache = {
+ .l1i_cache = &(CPUCacheInfo) {
.type = ICACHE,
.level = 1,
.size = 64 * KiB,
@@ -1180,7 +1180,7 @@ static CPUCaches epyc_cache_info = {
.self_init = 1,
.no_invd_sharing = true,
},
- .l2_cache = {
+ .l2_cache = &(CPUCacheInfo) {
.type = UNIFIED_CACHE,
.level = 2,
.size = 512 * KiB,
@@ -1190,7 +1190,7 @@ static CPUCaches epyc_cache_info = {
.sets = 1024,
.lines_per_tag = 1,
},
- .l3_cache = {
+ .l3_cache = &(CPUCacheInfo) {
.type = UNIFIED_CACHE,
.level = 3,
.size = 8 * MiB,
@@ -3384,9 +3384,8 @@ static void x86_cpu_load_def(X86CPU *cpu, X86CPUDefinition *def, Error **errp)
env->features[w] = def->features[w];
}

- /* Store Cache information from the X86CPUDefinition if available */
- env->cache_info = def->cache_info;
- cpu->legacy_cache = def->cache_info ? 0 : 1;
+ /* legacy-cache defaults to 'off' if CPU model provides cache info */
+ cpu->legacy_cache = !def->cache_info;

/* Special cases not set in the X86CPUDefinition structs: */
/* TODO: in-kernel irqchip for hvf */
@@ -3737,21 +3736,11 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
if (!cpu->enable_l3_cache) {
*ecx = 0;
} else {
- if (env->cache_info && !cpu->legacy_cache) {
- *ecx = cpuid2_cache_descriptor(&env->cache_info->l3_cache);
- } else {
- *ecx = cpuid2_cache_descriptor(&legacy_l3_cache);
- }
- }
- if (env->cache_info && !cpu->legacy_cache) {
- *edx = (cpuid2_cache_descriptor(&env->cache_info->l1d_cache) << 16) |
- (cpuid2_cache_descriptor(&env->cache_info->l1i_cache) << 8) |
- (cpuid2_cache_descriptor(&env->cache_info->l2_cache));
- } else {
- *edx = (cpuid2_cache_descriptor(&legacy_l1d_cache) << 16) |
- (cpuid2_cache_descriptor(&legacy_l1i_cache) << 8) |
- (cpuid2_cache_descriptor(&legacy_l2_cache_cpuid2));
+ *ecx = cpuid2_cache_descriptor(env->cache_info_cpuid2.l3_cache);
}
+ *edx = (cpuid2_cache_descriptor(env->cache_info_cpuid2.l1d_cache) << 16) |
+ (cpuid2_cache_descriptor(env->cache_info_cpuid2.l1i_cache) << 8) |
+ (cpuid2_cache_descriptor(env->cache_info_cpuid2.l2_cache));
break;
case 4:
/* cache info: needed for Core compatibility */
@@ -3764,35 +3753,27 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
}
} else {
*eax = 0;
- CPUCacheInfo *l1d, *l1i, *l2, *l3;
- if (env->cache_info && !cpu->legacy_cache) {
- l1d = &env->cache_info->l1d_cache;
- l1i = &env->cache_info->l1i_cache;
- l2 = &env->cache_info->l2_cache;
- l3 = &env->cache_info->l3_cache;
- } else {
- l1d = &legacy_l1d_cache;
- l1i = &legacy_l1i_cache;
- l2 = &legacy_l2_cache;
- l3 = &legacy_l3_cache;
- }
switch (count) {
case 0: /* L1 dcache info */
- encode_cache_cpuid4(l1d, 1, cs->nr_cores,
+ encode_cache_cpuid4(env->cache_info_cpuid4.l1d_cache,
+ 1, cs->nr_cores,
eax, ebx, ecx, edx);
break;
case 1: /* L1 icache info */
- encode_cache_cpuid4(l1i, 1, cs->nr_cores,
+ encode_cache_cpuid4(env->cache_info_cpuid4.l1i_cache,
+ 1, cs->nr_cores,
eax, ebx, ecx, edx);
break;
case 2: /* L2 cache info */
- encode_cache_cpuid4(l2, cs->nr_threads, cs->nr_cores,
+ encode_cache_cpuid4(env->cache_info_cpuid4.l2_cache,
+ cs->nr_threads, cs->nr_cores,
eax, ebx, ecx, edx);
break;
case 3: /* L3 cache info */
pkg_offset = apicid_pkg_offset(cs->nr_cores, cs->nr_threads);
if (cpu->enable_l3_cache) {
- encode_cache_cpuid4(l3, (1 << pkg_offset), cs->nr_cores,
+ encode_cache_cpuid4(env->cache_info_cpuid4.l3_cache,
+ (1 << pkg_offset), cs->nr_cores,
eax, ebx, ecx, edx);
break;
}
@@ -4005,13 +3986,8 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
(L1_ITLB_2M_ASSOC << 8) | (L1_ITLB_2M_ENTRIES);
*ebx = (L1_DTLB_4K_ASSOC << 24) | (L1_DTLB_4K_ENTRIES << 16) | \
(L1_ITLB_4K_ASSOC << 8) | (L1_ITLB_4K_ENTRIES);
- if (env->cache_info && !cpu->legacy_cache) {
- *ecx = encode_cache_cpuid80000005(&env->cache_info->l1d_cache);
- *edx = encode_cache_cpuid80000005(&env->cache_info->l1i_cache);
- } else {
- *ecx = encode_cache_cpuid80000005(&legacy_l1d_cache_amd);
- *edx = encode_cache_cpuid80000005(&legacy_l1i_cache_amd);
- }
+ *ecx = encode_cache_cpuid80000005(env->cache_info_amd.l1d_cache);
+ *edx = encode_cache_cpuid80000005(env->cache_info_amd.l1i_cache);
break;
case 0x80000006:
/* cache info (L2 cache) */
@@ -4027,17 +4003,10 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
(L2_DTLB_4K_ENTRIES << 16) | \
(AMD_ENC_ASSOC(L2_ITLB_4K_ASSOC) << 12) | \
(L2_ITLB_4K_ENTRIES);
- if (env->cache_info && !cpu->legacy_cache) {
- encode_cache_cpuid80000006(&env->cache_info->l2_cache,
- cpu->enable_l3_cache ?
- &env->cache_info->l3_cache : NULL,
- ecx, edx);
- } else {
- encode_cache_cpuid80000006(&legacy_l2_cache_amd,
- cpu->enable_l3_cache ?
- &legacy_l3_cache : NULL,
- ecx, edx);
- }
+ encode_cache_cpuid80000006(env->cache_info_amd.l2_cache,
+ cpu->enable_l3_cache ?
+ env->cache_info_amd.l3_cache : NULL,
+ ecx, edx);
break;
case 0x80000007:
*eax = 0;
@@ -4080,34 +4049,22 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
break;
case 0x8000001D:
*eax = 0;
- CPUCacheInfo *l1d, *l1i, *l2, *l3;
- if (env->cache_info && !cpu->legacy_cache) {
- l1d = &env->cache_info->l1d_cache;
- l1i = &env->cache_info->l1i_cache;
- l2 = &env->cache_info->l2_cache;
- l3 = &env->cache_info->l3_cache;
- } else {
- l1d = &legacy_l1d_cache_amd;
- l1i = &legacy_l1i_cache_amd;
- l2 = &legacy_l2_cache_amd;
- l3 = &legacy_l3_cache;
- }
switch (count) {
case 0: /* L1 dcache info */
- encode_cache_cpuid8000001d(l1d, cs->nr_threads,
- eax, ebx, ecx, edx);
+ encode_cache_cpuid8000001d(env->cache_info_amd.l1d_cache,
+ cs->nr_threads, eax, ebx, ecx, edx);
break;
case 1: /* L1 icache info */
- encode_cache_cpuid8000001d(l1i, cs->nr_threads,
- eax, ebx, ecx, edx);
+ encode_cache_cpuid8000001d(env->cache_info_amd.l1i_cache,
+ cs->nr_threads, eax, ebx, ecx, edx);
break;
case 2: /* L2 cache info */
- encode_cache_cpuid8000001d(l2, cs->nr_threads,
- eax, ebx, ecx, edx);
+ encode_cache_cpuid8000001d(env->cache_info_amd.l2_cache,
+ cs->nr_threads, eax, ebx, ecx, edx);
break;
case 3: /* L3 cache info */
- encode_cache_cpuid8000001d(l3, cs->nr_threads,
- eax, ebx, ecx, edx);
+ encode_cache_cpuid8000001d(env->cache_info_amd.l3_cache,
+ cs->nr_threads, eax, ebx, ecx, edx);
break;
default: /* end of info */
*eax = *ebx = *ecx = *edx = 0;
@@ -4770,6 +4727,37 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
cpu->phys_bits = 32;
}
}
+
+ /* Cache information initialization */
+ if (!cpu->legacy_cache) {
+ if (!xcc->cpu_def || !xcc->cpu_def->cache_info) {
+ char *name = x86_cpu_class_get_model_name(xcc);
+ error_setg(errp,
+ "CPU model '%s' doesn't support legacy-cache=off", name);
+ g_free(name);
+ return;
+ }
+ env->cache_info_cpuid2 = env->cache_info_cpuid4 = env->cache_info_amd =
+ *xcc->cpu_def->cache_info;
+ } else {
+ /* Build legacy cache information */
+ env->cache_info_cpuid2.l1d_cache = &legacy_l1d_cache;
+ env->cache_info_cpuid2.l1i_cache = &legacy_l1i_cache;
+ env->cache_info_cpuid2.l2_cache = &legacy_l2_cache_cpuid2;
+ env->cache_info_cpuid2.l3_cache = &legacy_l3_cache;
+
+ env->cache_info_cpuid4.l1d_cache = &legacy_l1d_cache;
+ env->cache_info_cpuid4.l1i_cache = &legacy_l1i_cache;
+ env->cache_info_cpuid4.l2_cache = &legacy_l2_cache;
+ env->cache_info_cpuid4.l3_cache = &legacy_l3_cache;
+
+ env->cache_info_amd.l1d_cache = &legacy_l1d_cache_amd;
+ env->cache_info_amd.l1i_cache = &legacy_l1i_cache_amd;
+ env->cache_info_amd.l2_cache = &legacy_l2_cache_amd;
+ env->cache_info_amd.l3_cache = &legacy_l3_cache;
+ }
+
+
cpu_exec_realizefn(cs, &local_err);
if (local_err != NULL) {
error_propagate(errp, local_err);
@@ -5252,11 +5240,10 @@ static Property x86_cpu_properties[] = {
DEFINE_PROP_BOOL("vmware-cpuid-freq", X86CPU, vmware_cpuid_freq, true),
DEFINE_PROP_BOOL("tcg-cpuid", X86CPU, expose_tcg, true),
/*
- * lecacy_cache defaults to CPU model being chosen. This is set in
- * x86_cpu_load_def based on cache_info which is initialized in
- * builtin_x86_defs
+ * lecacy_cache defaults to true unless the CPU model provides its
+ * own cache information (see x86_cpu_load_def()).
*/
- DEFINE_PROP_BOOL("legacy-cache", X86CPU, legacy_cache, false),
+ DEFINE_PROP_BOOL("legacy-cache", X86CPU, legacy_cache, true),

/*
* From "Requirements for Implementing the Microsoft
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 1f9ccd47d9..e64b7da997 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1098,10 +1098,10 @@ typedef struct CPUCacheInfo {

typedef struct CPUCaches {
- CPUCacheInfo l1d_cache;
- CPUCacheInfo l1i_cache;
- CPUCacheInfo l2_cache;
- CPUCacheInfo l3_cache;
+ CPUCacheInfo *l1d_cache;
+ CPUCacheInfo *l1i_cache;
+ CPUCacheInfo *l2_cache;
+ CPUCacheInfo *l3_cache;
} CPUCaches;

typedef struct CPUX86State {
@@ -1289,7 +1289,11 @@ typedef struct CPUX86State {
/* Features that were explicitly enabled/disabled */
FeatureWordArray user_features;
uint32_t cpuid_model[12];
- CPUCaches *cache_info;
+ /* Cache information for CPUID. When legacy-cache=on, the cache data
+ * on each CPUID leaf will be different, because we keep compatibility
+ * with old QEMU versions.
+ */
+ CPUCaches cache_info_cpuid2, cache_info_cpuid4, cache_info_amd;

/* MTRRs */
uint64_t mtrr_fixed[11];
--
2.17.0