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UBUNTU: SAUCE: x86/cacheinfo: Delete global num_cache_leaves

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BugLink: https://bugs.launchpad.net/bugs/2049793

Linux remembers cpu_cachinfo::num_leaves per CPU, but x86 initializes all
CPUs from the same global "num_cache_leaves".

This is erroneous on systems such as Meteor Lake, where each CPU has a
distinct num_leaves value. Delete the global "num_cache_leaves" and
initialize num_leaves on each CPU.

Cc: Andreas Herrmann <aherrmann@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Yu <yu.c.chen@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Radu Rendec <rrendec@redhat.com>
Cc: Pierre Gondois <Pierre.Gondois@arm.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: stable@vger.kernel.org
Reviewed-by: Len Brown <len.brown@intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
(cherry-picked from https://lore.kernel.org/all/20231212222519.12834-4-ricardo.neri-calderon@linux.intel.com/raw)
Signed-off-by: You-Sheng Yang <vicamo.yang@canonical.com>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
This commit is contained in:
Ricardo Neri
2024-03-04 18:32:05 +08:00
committed by Paolo Pisati
parent c451fde27d
commit fab46ec65b
1 changed files with 26 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files
arch/x86/kernel/cpu/cacheinfo.c
+26 -18
View File
@@ -178,7 +178,16 @@ struct _cpuid4_info_regs {
struct amd_northbridge *nb;
};
static unsigned short num_cache_leaves;
static inline unsigned int get_num_cache_leaves(unsigned int cpu)
{
return get_cpu_cacheinfo(cpu)->num_leaves;
}
static inline void
set_num_cache_leaves(unsigned int nr_leaves, unsigned int cpu)
{
get_cpu_cacheinfo(cpu)->num_leaves = nr_leaves;
}
/* AMD doesn't have CPUID4. Emulate it here to report the same
information to the user. This makes some assumptions about the machine:
@@ -718,19 +727,21 @@ void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c)
void init_amd_cacheinfo(struct cpuinfo_x86 *c)
{
unsigned int cpu = c->cpu_index;
if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
num_cache_leaves = find_num_cache_leaves(c);
set_num_cache_leaves(find_num_cache_leaves(c), cpu);
} else if (c->extended_cpuid_level >= 0x80000006) {
if (cpuid_edx(0x80000006) & 0xf000)
num_cache_leaves = 4;
set_num_cache_leaves(4, cpu);
else
num_cache_leaves = 3;
set_num_cache_leaves(3, cpu);
}
}
void init_hygon_cacheinfo(struct cpuinfo_x86 *c)
{
num_cache_leaves = find_num_cache_leaves(c);
set_num_cache_leaves(find_num_cache_leaves(c), c->cpu_index);
}
void init_intel_cacheinfo(struct cpuinfo_x86 *c)
@@ -742,19 +753,19 @@ void init_intel_cacheinfo(struct cpuinfo_x86 *c)
unsigned int l2_id = 0, l3_id = 0, num_threads_sharing, index_msb;
if (c->cpuid_level > 3) {
static int is_initialized;
if (is_initialized == 0) {
/* Init num_cache_leaves from boot CPU */
num_cache_leaves = find_num_cache_leaves(c);
is_initialized++;
}
/*
* There should be at least one leaf. A non-zero value means
* that the number of leaves has been initialized.
*/
if (!get_num_cache_leaves(c->cpu_index))
set_num_cache_leaves(find_num_cache_leaves(c),
c->cpu_index);
/*
* Whenever possible use cpuid(4), deterministic cache
* parameters cpuid leaf to find the cache details
*/
for (i = 0; i < num_cache_leaves; i++) {
for (i = 0; i < get_num_cache_leaves(c->cpu_index); i++) {
struct _cpuid4_info_regs this_leaf = {};
int retval;
@@ -790,14 +801,14 @@ void init_intel_cacheinfo(struct cpuinfo_x86 *c)
* Don't use cpuid2 if cpuid4 is supported. For P4, we use cpuid2 for
* trace cache
*/
if ((num_cache_leaves == 0 || c->x86 == 15) && c->cpuid_level > 1) {
if ((!get_num_cache_leaves(c->cpu_index) || c->x86 == 15) && c->cpuid_level > 1) {
/* supports eax=2 call */
int j, n;
unsigned int regs[4];
unsigned char *dp = (unsigned char *)regs;
int only_trace = 0;
if (num_cache_leaves != 0 && c->x86 == 15)
if (get_num_cache_leaves(c->cpu_index) && c->x86 == 15)
only_trace = 1;
/* Number of times to iterate */
@@ -993,12 +1004,9 @@ int init_cache_level(unsigned int cpu)
{
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
if (!num_cache_leaves)
return -ENOENT;
if (!this_cpu_ci)
return -EINVAL;
this_cpu_ci->num_levels = 3;
this_cpu_ci->num_leaves = num_cache_leaves;
return 0;
}