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Groups > linux.kernel > #1295181
| From | tip-bot for Fenghua Yu <tipbot@zytor.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [tip:x86/cache] x86/intel_rdt: Add L3 cache capacity bitmask management |
| Date | 2015-12-18 22:40 +0100 |
| Message-ID | <qHaUO-2Dm-7@gated-at.bofh.it> (permalink) |
| References | <qGN2b-48Z-43@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
Commit-ID: a424209c74c3c30fb1677075afa5d9277e01c46b
Gitweb: http://git.kernel.org/tip/a424209c74c3c30fb1677075afa5d9277e01c46b
Author: Fenghua Yu <fenghua.yu@intel.com>
AuthorDate: Thu, 17 Dec 2015 14:46:11 -0800
Committer: H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Fri, 18 Dec 2015 13:17:56 -0800
x86/intel_rdt: Add L3 cache capacity bitmask management
From: Vikas Shivappa <vikas.shivappa@linux.intel.com>
This patch adds different APIs to manage the L3 cache capacity bitmask.
The capacity bit mask(CBM) needs to have only contiguous bits set. The
current implementation has a global CBM for each class of service id.
There are APIs added to update the CBM via MSR write to IA32_L3_MASK_n
on all packages. Other APIs are to read and write entries to the
clos_cbm_table.
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Link: http://lkml.kernel.org/r/1450392376-6397-7-git-send-email-fenghua.yu@intel.com
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
---
arch/x86/include/asm/intel_rdt.h | 4 ++
arch/x86/kernel/cpu/intel_rdt.c | 133 ++++++++++++++++++++++++++++++++++++++-
2 files changed, 136 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h
index 88b7643..4f45dc8 100644
--- a/arch/x86/include/asm/intel_rdt.h
+++ b/arch/x86/include/asm/intel_rdt.h
@@ -3,6 +3,10 @@
#ifdef CONFIG_INTEL_RDT
+#define MAX_CBM_LENGTH 32
+#define IA32_L3_CBM_BASE 0xc90
+#define CBM_FROM_INDEX(x) (IA32_L3_CBM_BASE + x)
+
struct clos_cbm_table {
unsigned long l3_cbm;
unsigned int clos_refcnt;
diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index d79213a..6ad5b48 100644
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -34,8 +34,22 @@ static struct clos_cbm_table *cctable;
* closid availability bit map.
*/
unsigned long *closmap;
+/*
+ * Mask of CPUs for writing CBM values. We only need one CPU per-socket.
+ */
+static cpumask_t rdt_cpumask;
+/*
+ * Temporary cpumask used during hot cpu notificaiton handling. The usage
+ * is serialized by hot cpu locks.
+ */
+static cpumask_t tmp_cpumask;
static DEFINE_MUTEX(rdt_group_mutex);
+struct rdt_remote_data {
+ int msr;
+ u64 val;
+};
+
static inline void closid_get(u32 closid)
{
struct clos_cbm_table *cct = &cctable[closid];
@@ -82,11 +96,126 @@ static void closid_put(u32 closid)
closid_free(closid);
}
+static bool cbm_validate(unsigned long var)
+{
+ u32 max_cbm_len = boot_cpu_data.x86_cache_max_cbm_len;
+ unsigned long first_bit, zero_bit;
+ u64 max_cbm;
+
+ if (bitmap_weight(&var, max_cbm_len) < 1)
+ return false;
+
+ max_cbm = (1ULL << max_cbm_len) - 1;
+ if (var & ~max_cbm)
+ return false;
+
+ first_bit = find_first_bit(&var, max_cbm_len);
+ zero_bit = find_next_zero_bit(&var, max_cbm_len, first_bit);
+
+ if (find_next_bit(&var, max_cbm_len, zero_bit) < max_cbm_len)
+ return false;
+
+ return true;
+}
+
+static int clos_cbm_table_read(u32 closid, unsigned long *l3_cbm)
+{
+ u32 maxid = boot_cpu_data.x86_cache_max_closid;
+
+ lockdep_assert_held(&rdt_group_mutex);
+
+ if (closid >= maxid)
+ return -EINVAL;
+
+ *l3_cbm = cctable[closid].l3_cbm;
+
+ return 0;
+}
+
+/*
+ * clos_cbm_table_update() - Update a clos cbm table entry.
+ * @closid: the closid whose cbm needs to be updated
+ * @cbm: the new cbm value that has to be updated
+ *
+ * This assumes the cbm is validated as per the interface requirements
+ * and the cache allocation requirements(through the cbm_validate).
+ */
+static int clos_cbm_table_update(u32 closid, unsigned long cbm)
+{
+ u32 maxid = boot_cpu_data.x86_cache_max_closid;
+
+ lockdep_assert_held(&rdt_group_mutex);
+
+ if (closid >= maxid)
+ return -EINVAL;
+
+ cctable[closid].l3_cbm = cbm;
+
+ return 0;
+}
+
+static bool cbm_search(unsigned long cbm, u32 *closid)
+{
+ u32 maxid = boot_cpu_data.x86_cache_max_closid;
+ u32 i;
+
+ for (i = 0; i < maxid; i++) {
+ if (cctable[i].clos_refcnt &&
+ bitmap_equal(&cbm, &cctable[i].l3_cbm, MAX_CBM_LENGTH)) {
+ *closid = i;
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static void closcbm_map_dump(void)
+{
+ u32 i;
+
+ pr_debug("CBMMAP\n");
+ for (i = 0; i < boot_cpu_data.x86_cache_max_closid; i++) {
+ pr_debug("l3_cbm: 0x%x,clos_refcnt: %u\n",
+ (unsigned int)cctable[i].l3_cbm, cctable[i].clos_refcnt);
+ }
+}
+
+static void msr_cpu_update(void *arg)
+{
+ struct rdt_remote_data *info = arg;
+
+ wrmsrl(info->msr, info->val);
+}
+
+/*
+ * msr_update_all() - Update the msr for all packages.
+ */
+static inline void msr_update_all(int msr, u64 val)
+{
+ struct rdt_remote_data info;
+
+ info.msr = msr;
+ info.val = val;
+ on_each_cpu_mask(&rdt_cpumask, msr_cpu_update, &info, 1);
+}
+
+static inline bool rdt_cpumask_update(int cpu)
+{
+ cpumask_and(&tmp_cpumask, &rdt_cpumask, topology_core_cpumask(cpu));
+ if (cpumask_empty(&tmp_cpumask)) {
+ cpumask_set_cpu(cpu, &rdt_cpumask);
+ return true;
+ }
+
+ return false;
+}
+
static int __init intel_rdt_late_init(void)
{
struct cpuinfo_x86 *c = &boot_cpu_data;
u32 maxid, max_cbm_len;
- int err = 0, size;
+ int err = 0, size, i;
if (!cpu_has(c, X86_FEATURE_CAT_L3))
return -ENODEV;
@@ -109,6 +238,8 @@ static int __init intel_rdt_late_init(void)
goto out_err;
}
+ for_each_online_cpu(i)
+ rdt_cpumask_update(i);
pr_info("Intel cache allocation enabled\n");
out_err:
--
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[PATCH V16 00/11] x86: Intel Cache Allocation Technology Support "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[PATCH V16 01/11] x86/intel_cqm: Modify hot cpu notification handling "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[tip:x86/cache] x86/intel_cqm: Modify hot cpu notification handling tip-bot for Fenghua Yu <tipbot@zytor.com> - 2015-12-18 22:40 +0100
[PATCH V16 03/11] x86/intel_rdt: Cache Allocation documentation "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[tip:x86/cache] x86/intel_rdt: Cache Allocation documentation tip-bot for Fenghua Yu <tipbot@zytor.com> - 2015-12-18 22:40 +0100
[PATCH V16 07/11] x86/intel_rdt: Implement scheduling support for Intel RDT "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[tip:x86/cache] x86/intel_rdt: Implement scheduling support for Intel RDT tip-bot for Fenghua Yu <tipbot@zytor.com> - 2015-12-18 22:40 +0100
[PATCH V16 04/11] x86/intel_rdt: Add support for Cache Allocation detection "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[tip:x86/cache] x86/intel_rdt: Add support for Cache Allocation detection tip-bot for Fenghua Yu <tipbot@zytor.com> - 2015-12-18 22:40 +0100
[PATCH V16 09/11] x86/intel_rdt: Intel haswell Cache Allocation enumeration "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[tip:x86/cache] x86/intel_rdt: Intel haswell Cache Allocation enumeration tip-bot for Fenghua Yu <tipbot@zytor.com> - 2015-12-18 22:40 +0100
[PATCH V16 08/11] x86/intel_rdt: Hot cpu support for Cache Allocation "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[tip:x86/cache] x86/intel_rdt: Hot cpu support for Cache Allocation tip-bot for Fenghua Yu <tipbot@zytor.com> - 2015-12-18 22:40 +0100
[PATCH V16 06/11] x86/intel_rdt: Add L3 cache capacity bitmask management "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[tip:x86/cache] x86/intel_rdt: Add L3 cache capacity bitmask management tip-bot for Fenghua Yu <tipbot@zytor.com> - 2015-12-18 22:40 +0100
[PATCH V16 11/11] x86,cgroup/intel_rdt : Add a cgroup interface to manage Intel cache allocation "Fenghua Yu" <fenghua.yu@intel.com> - 2015-12-17 21:10 +0100
[tip:x86/cache] x86,cgroup/intel_rdt : Add a cgroup interface to manage Intel cache allocation tip-bot for Fenghua Yu <tipbot@zytor.com> - 2015-12-18 22:40 +0100
Re: [PATCH V16 11/11] x86,cgroup/intel_rdt : Add a cgroup interface to manage Intel cache allocation Thomas Gleixner <tglx@linutronix.de> - 2015-12-19 11:50 +0100
Re: [PATCH V16 11/11] x86,cgroup/intel_rdt : Add a cgroup interface to manage Intel cache allocation Marcelo Tosatti <mtosatti@redhat.com> - 2015-12-21 13:00 +0100
Re: [PATCH V16 11/11] x86,cgroup/intel_rdt : Add a cgroup interface to manage Intel cache allocation Thomas Gleixner <tglx@linutronix.de> - 2015-12-21 14:50 +0100
Re: [PATCH V16 11/11] x86,cgroup/intel_rdt : Add a cgroup interface to manage Intel cache allocation Luiz Capitulino <lcapitulino@redhat.com> - 2015-12-21 16:50 +0100
Re: [PATCH V16 11/11] x86,cgroup/intel_rdt : Add a cgroup interface to manage Intel cache allocation Marcelo Tosatti <mtosatti@redhat.com> - 2015-12-22 00:10 +0100
Re: [PATCH V16 00/11] x86: Intel Cache Allocation Technology Support Christoph Lameter <cl@linux.com> - 2015-12-18 18:50 +0100
Re: [PATCH V16 00/11] x86: Intel Cache Allocation Technology Support Marcelo Tosatti <mtosatti@redhat.com> - 2015-12-21 13:00 +0100
Re: [PATCH V16 00/11] x86: Intel Cache Allocation Technology Support Christoph Lameter <cl@linux.com> - 2015-12-21 14:00 +0100
Re: [PATCH V16 00/11] x86: Intel Cache Allocation Technology Support Luiz Capitulino <lcapitulino@redhat.com> - 2015-12-21 17:00 +0100
Re: [PATCH V16 00/11] x86: Intel Cache Allocation Technology Support Tejun Heo <tj@kernel.org> - 2015-12-23 17:00 +0100
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