mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-21 18:11:39 +00:00
Code Issues Releases Wiki Activity

x86/intel_rdt: Support L3 cache performance event of Broadwell

Browse source 
Broadwell microarchitecture supports pseudo-locking. Add support for
the L3 cache related performance events of these systems so that
the success of pseudo-locking can be measured more accurately on these
platforms.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Cc: vikas.shivappa@linux.intel.com
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: dave.hansen@intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/36c1414e9bd17c3faf440f32b644b9c879bcbae2.1529706536.git.reinette.chatre@intel.com
This commit is contained in:
Reinette Chatre 2018-06-22 15:42:29 -07:00 committed by Thomas Gleixner
parent 8a2fc0e1bc
commit f3be1e7b2c
2 changed files with 66 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

56
arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c
View file

@ -850,6 +850,8 @@ static int measure_cycles_lat_fn(void *_plr)
static int measure_cycles_perf_fn(void *_plr)
{
unsigned long long l3_hits = 0, l3_miss = 0;
u64 l3_hit_bits = 0, l3_miss_bits = 0;
struct pseudo_lock_region *plr = _plr;
unsigned long long l2_hits, l2_miss;
u64 l2_hit_bits, l2_miss_bits;
@ -883,6 +885,16 @@ static int measure_cycles_perf_fn(void *_plr)
* L2_HIT 02H
* L1_MISS 08H
* L2_MISS 10H
*
* On Broadwell Microarchitecture the MEM_LOAD_UOPS_RETIRED event
* has two "no fix" errata associated with it: BDM35 and BDM100. On
* this platform we use the following events instead:
* L2_RQSTS 24H (Documented in https://download.01.org/perfmon/BDW/)
* REFERENCES FFH
* MISS 3FH
* LONGEST_LAT_CACHE 2EH (Documented in SDM)
* REFERENCE 4FH
* MISS 41H
*/
/*
@ -901,6 +913,14 @@ static int measure_cycles_perf_fn(void *_plr)
l2_hit_bits = (0x52ULL << 16) | (0x2 << 8) | 0xd1;
l2_miss_bits = (0x52ULL << 16) | (0x10 << 8) | 0xd1;
break;
case INTEL_FAM6_BROADWELL_X:
/* On BDW the l2_hit_bits count references, not hits */
l2_hit_bits = (0x52ULL << 16) | (0xff << 8) | 0x24;
l2_miss_bits = (0x52ULL << 16) | (0x3f << 8) | 0x24;
/* On BDW the l3_hit_bits count references, not hits */
l3_hit_bits = (0x52ULL << 16) | (0x4f << 8) | 0x2e;
l3_miss_bits = (0x52ULL << 16) | (0x41 << 8) | 0x2e;
break;
default:
goto out;
}
@ -917,9 +937,21 @@ static int measure_cycles_perf_fn(void *_plr)
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 1, 0x0);
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_PERFCTR0, 0x0);
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_PERFCTR0 + 1, 0x0);
if (l3_hit_bits > 0) {
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 2, 0x0);
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 3, 0x0);
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_PERFCTR0 + 2, 0x0);
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_PERFCTR0 + 3, 0x0);
}
/* Set and enable the L2 counters */
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0, l2_hit_bits);
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 1, l2_miss_bits);
if (l3_hit_bits > 0) {
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 2,
l3_hit_bits);
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 3,
l3_miss_bits);
}
mem_r = plr->kmem;
size = plr->size;
line_size = plr->line_size;
@ -937,11 +969,35 @@ static int measure_cycles_perf_fn(void *_plr)
l2_hit_bits & ~(0x40ULL << 16));
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 1,
l2_miss_bits & ~(0x40ULL << 16));
if (l3_hit_bits > 0) {
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 2,
l3_hit_bits & ~(0x40ULL << 16));
pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 3,
l3_miss_bits & ~(0x40ULL << 16));
}
l2_hits = native_read_pmc(0);
l2_miss = native_read_pmc(1);
if (l3_hit_bits > 0) {
l3_hits = native_read_pmc(2);
l3_miss = native_read_pmc(3);
}
wrmsr(MSR_MISC_FEATURE_CONTROL, 0x0, 0x0);
local_irq_enable();
/*
* On BDW we count references and misses, need to adjust. Sometimes
* the "hits" counter is a bit more than the references, for
* example, x references but x + 1 hits. To not report invalid
* hit values in this case we treat that as misses eaqual to
* references.
*/
if (boot_cpu_data.x86_model == INTEL_FAM6_BROADWELL_X)
l2_hits -= (l2_miss > l2_hits ? l2_hits : l2_miss);
trace_pseudo_lock_l2(l2_hits, l2_miss);
if (l3_hit_bits > 0) {
if (boot_cpu_data.x86_model == INTEL_FAM6_BROADWELL_X)
l3_hits -= (l3_miss > l3_hits ? l3_hits : l3_miss);
trace_pseudo_lock_l3(l3_hits, l3_miss);
}
out:
plr->thread_done = 1;

10
arch/x86/kernel/cpu/intel_rdt_pseudo_lock_event.h
View file

@ -25,6 +25,16 @@ TRACE_EVENT(pseudo_lock_l2,
TP_printk("hits=%llu miss=%llu",
__entry->l2_hits, __entry->l2_miss));
TRACE_EVENT(pseudo_lock_l3,
TP_PROTO(u64 l3_hits, u64 l3_miss),
TP_ARGS(l3_hits, l3_miss),
TP_STRUCT__entry(__field(u64, l3_hits)
__field(u64, l3_miss)),
TP_fast_assign(__entry->l3_hits = l3_hits;
__entry->l3_miss = l3_miss;),
TP_printk("hits=%llu miss=%llu",
__entry->l3_hits, __entry->l3_miss));
#endif /* _TRACE_PSEUDO_LOCK_H */
#undef TRACE_INCLUDE_PATH