[PATCH 2/2] x86, cacheinfo: Enable L3 CID only on AMD

From: Borislav Petkov
Date: Thu Feb 18 2010 - 15:11:12 EST


On Tue, Feb 16, 2010 at 03:02:46PM +0100, Ingo Molnar wrote:
>
> * tip-bot for Borislav Petkov <borislav.petkov@xxxxxxx> wrote:
>
> > Commit-ID: 472bf751b56324f8c96d97ada3c9dcdc8b2ec4f7
> > Gitweb: http://git.kernel.org/tip/472bf751b56324f8c96d97ada3c9dcdc8b2ec4f7
> > Author: Borislav Petkov <borislav.petkov@xxxxxxx>
> > AuthorDate: Mon, 15 Feb 2010 12:43:56 +0100
> > Committer: H. Peter Anvin <hpa@xxxxxxxxx>
> > CommitDate: Mon, 15 Feb 2010 12:32:48 -0800
> >
> > x86, cacheinfo: Remove NUMA dependency, fix for D1 Isntanbul
>
> FYI, this commit broke the build in -tip testing:
>
> arch/x86/built-in.o: In function `store_cache_disable':
> intel_cacheinfo.c:(.text+0xc509): undefined reference to `amd_get_nb_id'
> arch/x86/built-in.o: In function `show_cache_disable':
> intel_cacheinfo.c:(.text+0xc7d3): undefined reference to `amd_get_nb_id'

How's that:

---
From: Borislav Petkov <borislav.petkov@xxxxxxx>
Date: Thu, 18 Feb 2010 19:37:14 +0100
Subject: [PATCH 2/2] x86, cacheinfo: Enable L3 CID only on AMD

Final stage linking can fail with

arch/x86/built-in.o: In function `store_cache_disable':
intel_cacheinfo.c:(.text+0xc509): undefined reference to `amd_get_nb_id'
arch/x86/built-in.o: In function `show_cache_disable':
intel_cacheinfo.c:(.text+0xc7d3): undefined reference to `amd_get_nb_id'

when CONFIG_CPU_SUP_AMD is not enabled because the amd_get_nb_id
helper is defined in AMD-specific code but also used in generic code
(intel_cacheinfo.c). Reorganize the L3 cache index disable code under
CONFIG_CPU_SUP_AMD since it is AMD-only anyway.

Signed-off-by: Borislav Petkov <borislav.petkov@xxxxxxx>
---
arch/x86/kernel/cpu/intel_cacheinfo.c | 186 +++++++++++++++++----------------
1 files changed, 98 insertions(+), 88 deletions(-)

diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
index be5f5c2..d440123 100644
--- a/arch/x86/kernel/cpu/intel_cacheinfo.c
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -293,6 +293,13 @@ amd_cpuid4(int leaf, union _cpuid4_leaf_eax *eax,
(ebx->split.ways_of_associativity + 1) - 1;
}

+struct _cache_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct _cpuid4_info *, char *);
+ ssize_t (*store)(struct _cpuid4_info *, const char *, size_t count);
+};
+
+#ifdef CONFIG_CPU_SUP_AMD
static unsigned int __cpuinit amd_calc_l3_indices(void)
{
/*
@@ -303,7 +310,7 @@ static unsigned int __cpuinit amd_calc_l3_indices(void)
int node = cpu_to_node(cpu);
struct pci_dev *dev = node_to_k8_nb_misc(node);
unsigned int sc0, sc1, sc2, sc3;
- u32 val;
+ u32 val = 0;

pci_read_config_dword(dev, 0x1C4, &val);

@@ -335,6 +342,94 @@ amd_check_l3_disable(int index, struct _cpuid4_info_regs *this_leaf)
this_leaf->l3_indices = amd_calc_l3_indices();
}

+static ssize_t show_cache_disable(struct _cpuid4_info *this_leaf, char *buf,
+ unsigned int index)
+{
+ int cpu = cpumask_first(to_cpumask(this_leaf->shared_cpu_map));
+ int node = amd_get_nb_id(cpu);
+ struct pci_dev *dev = node_to_k8_nb_misc(node);
+ unsigned int reg = 0;
+
+ if (!this_leaf->can_disable)
+ return -EINVAL;
+
+ if (!dev)
+ return -EINVAL;
+
+ pci_read_config_dword(dev, 0x1BC + index * 4, &reg);
+ return sprintf(buf, "0x%08x\n", reg);
+}
+
+#define SHOW_CACHE_DISABLE(index) \
+static ssize_t \
+show_cache_disable_##index(struct _cpuid4_info *this_leaf, char *buf) \
+{ \
+ return show_cache_disable(this_leaf, buf, index); \
+}
+SHOW_CACHE_DISABLE(0)
+SHOW_CACHE_DISABLE(1)
+
+static ssize_t store_cache_disable(struct _cpuid4_info *this_leaf,
+ const char *buf, size_t count, unsigned int index)
+{
+ int cpu = cpumask_first(to_cpumask(this_leaf->shared_cpu_map));
+ int node = amd_get_nb_id(cpu);
+ struct pci_dev *dev = node_to_k8_nb_misc(node);
+ unsigned long val = 0;
+
+#define SUBCACHE_MASK (3UL << 20)
+#define SUBCACHE_INDEX 0xfff
+
+ if (!this_leaf->can_disable)
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (!dev)
+ return -EINVAL;
+
+ if (strict_strtoul(buf, 10, &val) < 0)
+ return -EINVAL;
+
+ /* do not allow writes outside of allowed bits */
+ if ((val & ~(SUBCACHE_MASK | SUBCACHE_INDEX)) ||
+ ((val & SUBCACHE_INDEX) > this_leaf->l3_indices))
+ return -EINVAL;
+
+ val |= BIT(30);
+ pci_write_config_dword(dev, 0x1BC + index * 4, val);
+ /*
+ * We need to WBINVD on a core on the node containing the L3 cache which
+ * indices we disable therefore a simple wbinvd() is not sufficient.
+ */
+ wbinvd_on_cpu(cpu);
+ pci_write_config_dword(dev, 0x1BC + index * 4, val | BIT(31));
+ return count;
+}
+
+#define STORE_CACHE_DISABLE(index) \
+static ssize_t \
+store_cache_disable_##index(struct _cpuid4_info *this_leaf, \
+ const char *buf, size_t count) \
+{ \
+ return store_cache_disable(this_leaf, buf, count, index); \
+}
+STORE_CACHE_DISABLE(0)
+STORE_CACHE_DISABLE(1)
+
+static struct _cache_attr cache_disable_0 = __ATTR(cache_disable_0, 0644,
+ show_cache_disable_0, store_cache_disable_0);
+static struct _cache_attr cache_disable_1 = __ATTR(cache_disable_1, 0644,
+ show_cache_disable_1, store_cache_disable_1);
+
+#else /* CONFIG_CPU_SUP_AMD */
+static void __cpuinit
+amd_check_l3_disable(int index, struct _cpuid4_info_regs *this_leaf)
+{
+};
+#endif /* CONFIG_CPU_SUP_AMD */
+
static int
__cpuinit cpuid4_cache_lookup_regs(int index,
struct _cpuid4_info_regs *this_leaf)
@@ -740,88 +835,6 @@ static ssize_t show_type(struct _cpuid4_info *this_leaf, char *buf)
#define to_object(k) container_of(k, struct _index_kobject, kobj)
#define to_attr(a) container_of(a, struct _cache_attr, attr)

-static ssize_t show_cache_disable(struct _cpuid4_info *this_leaf, char *buf,
- unsigned int index)
-{
- int cpu = cpumask_first(to_cpumask(this_leaf->shared_cpu_map));
- int node = amd_get_nb_id(cpu);
- struct pci_dev *dev = node_to_k8_nb_misc(node);
- unsigned int reg = 0;
-
- if (!this_leaf->can_disable)
- return -EINVAL;
-
- if (!dev)
- return -EINVAL;
-
- pci_read_config_dword(dev, 0x1BC + index * 4, &reg);
- return sprintf(buf, "0x%08x\n", reg);
-}
-
-#define SHOW_CACHE_DISABLE(index) \
-static ssize_t \
-show_cache_disable_##index(struct _cpuid4_info *this_leaf, char *buf) \
-{ \
- return show_cache_disable(this_leaf, buf, index); \
-}
-SHOW_CACHE_DISABLE(0)
-SHOW_CACHE_DISABLE(1)
-
-static ssize_t store_cache_disable(struct _cpuid4_info *this_leaf,
- const char *buf, size_t count, unsigned int index)
-{
- int cpu = cpumask_first(to_cpumask(this_leaf->shared_cpu_map));
- int node = amd_get_nb_id(cpu);
- struct pci_dev *dev = node_to_k8_nb_misc(node);
- unsigned long val = 0;
-
-#define SUBCACHE_MASK (3UL << 20)
-#define SUBCACHE_INDEX 0xfff
-
- if (!this_leaf->can_disable)
- return -EINVAL;
-
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
-
- if (!dev)
- return -EINVAL;
-
- if (strict_strtoul(buf, 10, &val) < 0)
- return -EINVAL;
-
- /* do not allow writes outside of allowed bits */
- if ((val & ~(SUBCACHE_MASK | SUBCACHE_INDEX)) ||
- ((val & SUBCACHE_INDEX) > this_leaf->l3_indices))
- return -EINVAL;
-
- val |= BIT(30);
- pci_write_config_dword(dev, 0x1BC + index * 4, val);
- /*
- * We need to WBINVD on a core on the node containing the L3 cache which
- * indices we disable therefore a simple wbinvd() is not sufficient.
- */
- wbinvd_on_cpu(cpu);
- pci_write_config_dword(dev, 0x1BC + index * 4, val | BIT(31));
- return count;
-}
-
-#define STORE_CACHE_DISABLE(index) \
-static ssize_t \
-store_cache_disable_##index(struct _cpuid4_info *this_leaf, \
- const char *buf, size_t count) \
-{ \
- return store_cache_disable(this_leaf, buf, count, index); \
-}
-STORE_CACHE_DISABLE(0)
-STORE_CACHE_DISABLE(1)
-
-struct _cache_attr {
- struct attribute attr;
- ssize_t (*show)(struct _cpuid4_info *, char *);
- ssize_t (*store)(struct _cpuid4_info *, const char *, size_t count);
-};
-
#define define_one_ro(_name) \
static struct _cache_attr _name = \
__ATTR(_name, 0444, show_##_name, NULL)
@@ -836,11 +849,6 @@ define_one_ro(size);
define_one_ro(shared_cpu_map);
define_one_ro(shared_cpu_list);

-static struct _cache_attr cache_disable_0 = __ATTR(cache_disable_0, 0644,
- show_cache_disable_0, store_cache_disable_0);
-static struct _cache_attr cache_disable_1 = __ATTR(cache_disable_1, 0644,
- show_cache_disable_1, store_cache_disable_1);
-
#define DEFAULT_SYSFS_CACHE_ATTRS \
&type.attr, \
&level.attr, \
@@ -859,8 +867,10 @@ static struct attribute *default_attrs[] = {

static struct attribute *default_l3_attrs[] = {
DEFAULT_SYSFS_CACHE_ATTRS,
+#ifdef CONFIG_CPU_SUP_AMD
&cache_disable_0.attr,
&cache_disable_1.attr,
+#endif
NULL
};

--
1.6.4.2


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