[GIT PULL] perf fixes

[Ingo Molnar]

Linus,

Please pull the latest perf-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
perf-urgent-for-linus

   # HEAD: 8fc31ce8896fc3cea1d79688c8ff950ad4e73afe perf/core: Remove invalid 
warning from list_update_cgroup_even()t

A bogus warning fix, a counter width handling fix affecting certain machines, 
plus 
a oneliner hw-enablement patch for Knights Mill CPUs.

 Thanks,

        Ingo

------------------>
David Carrillo-Cisneros (1):
      perf/core: Remove invalid warning from list_update_cgroup_even()t

Peter Zijlstra (Intel) (1):
      perf/x86: Fix full width counter, counter overflow

Piotr Luc (1):
      perf/x86/intel: Enable C-state residency events for Knights Mill


 arch/x86/events/core.c         |  2 +-
 arch/x86/events/intel/core.c   |  2 +-
 arch/x86/events/intel/cstate.c |  1 +
 kernel/events/core.c           | 19 ++++++++-----------
 4 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 9d4bf3ab049e..6e395c996900 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -69,7 +69,7 @@ u64 x86_perf_event_update(struct perf_event *event)
        int shift = 64 - x86_pmu.cntval_bits;
        u64 prev_raw_count, new_raw_count;
        int idx = hwc->idx;
-       s64 delta;
+       u64 delta;
 
        if (idx == INTEL_PMC_IDX_FIXED_BTS)
                return 0;
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index a74a2dbc0180..cb8522290e6a 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -4034,7 +4034,7 @@ __init int intel_pmu_init(void)
 
        /* Support full width counters using alternative MSR range */
        if (x86_pmu.intel_cap.full_width_write) {
-               x86_pmu.max_period = x86_pmu.cntval_mask;
+               x86_pmu.max_period = x86_pmu.cntval_mask >> 1;
                x86_pmu.perfctr = MSR_IA32_PMC0;
                pr_cont("full-width counters, ");
        }
diff --git a/arch/x86/events/intel/cstate.c b/arch/x86/events/intel/cstate.c
index 4f5ac726335f..da51e5a3e2ff 100644
--- a/arch/x86/events/intel/cstate.c
+++ b/arch/x86/events/intel/cstate.c
@@ -540,6 +540,7 @@ static const struct x86_cpu_id intel_cstates_match[] 
__initconst = {
        X86_CSTATES_MODEL(INTEL_FAM6_SKYLAKE_DESKTOP, snb_cstates),
 
        X86_CSTATES_MODEL(INTEL_FAM6_XEON_PHI_KNL, knl_cstates),
+       X86_CSTATES_MODEL(INTEL_FAM6_XEON_PHI_KNM, knl_cstates),
        { },
 };
 MODULE_DEVICE_TABLE(x86cpu, intel_cstates_match);
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 6ee1febdf6ff..02c8421f8c01 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -903,17 +903,14 @@ list_update_cgroup_event(struct perf_event *event,
         */
        cpuctx = __get_cpu_context(ctx);
 
-       /* Only set/clear cpuctx->cgrp if current task uses event->cgrp. */
-       if (perf_cgroup_from_task(current, ctx) != event->cgrp) {
-               /*
-                * We are removing the last cpu event in this context.
-                * If that event is not active in this cpu, cpuctx->cgrp
-                * should've been cleared by perf_cgroup_switch.
-                */
-               WARN_ON_ONCE(!add && cpuctx->cgrp);
-               return;
-       }
-       cpuctx->cgrp = add ? event->cgrp : NULL;
+       /*
+        * cpuctx->cgrp is NULL until a cgroup event is sched in or
+        * ctx->nr_cgroup == 0 .
+        */
+       if (add && perf_cgroup_from_task(current, ctx) == event->cgrp)
+               cpuctx->cgrp = event->cgrp;
+       else if (!add)
+               cpuctx->cgrp = NULL;
 }
 
 #else /* !CONFIG_CGROUP_PERF */