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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-05 17:00:53 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-05 17:00:53 (GMT) |
commit | a0e9c6efa585897f00eb22e67887e5a25482b1b8 (patch) | |
tree | bf77a44476211119b67fd3872745a58ea6787358 /arch/x86/kernel | |
parent | 5943334737b0447f7f3e6268bd6c7da7c02f5948 (diff) | |
parent | b44a2b53becf2485f484bd6bb6c1d963ebc339f8 (diff) | |
download | linux-a0e9c6efa585897f00eb22e67887e5a25482b1b8.tar.xz |
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"The biggest chunk of the changes are two regression fixes: a HT
workaround fix and an event-group scheduling fix. It's been verified
with 5 days of fuzzer testing.
Other fixes:
- eBPF fix
- a BIOS breakage detection fix
- PMU driver fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/pt: Fix a refactoring bug
perf/x86: Tweak broken BIOS rules during check_hw_exists()
perf/x86/intel/pt: Untangle pt_buffer_reset_markers()
perf: Disallow sparse AUX allocations for non-SG PMUs in overwrite mode
perf/x86: Improve HT workaround GP counter constraint
perf/x86: Fix event/group validation
perf: Fix race in BPF program unregister
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/cpu/perf_event.c | 83 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/perf_event.h | 24 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel.c | 45 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel_ds.c | 4 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel_pt.c | 36 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel_uncore.c | 9 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel_uncore.h | 1 |
7 files changed, 123 insertions, 79 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index 87848eb..4f7001f 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -190,6 +190,7 @@ static bool check_hw_exists(void) u64 val, val_fail, val_new= ~0; int i, reg, reg_fail, ret = 0; int bios_fail = 0; + int reg_safe = -1; /* * Check to see if the BIOS enabled any of the counters, if so @@ -204,6 +205,8 @@ static bool check_hw_exists(void) bios_fail = 1; val_fail = val; reg_fail = reg; + } else { + reg_safe = i; } } @@ -222,11 +225,22 @@ static bool check_hw_exists(void) } /* + * If all the counters are enabled, the below test will always + * fail. The tools will also become useless in this scenario. + * Just fail and disable the hardware counters. + */ + + if (reg_safe == -1) { + reg = reg_safe; + goto msr_fail; + } + + /* * Read the current value, change it and read it back to see if it * matches, this is needed to detect certain hardware emulators * (qemu/kvm) that don't trap on the MSR access and always return 0s. */ - reg = x86_pmu_event_addr(0); + reg = x86_pmu_event_addr(reg_safe); if (rdmsrl_safe(reg, &val)) goto msr_fail; val ^= 0xffffUL; @@ -611,6 +625,7 @@ struct sched_state { int event; /* event index */ int counter; /* counter index */ int unassigned; /* number of events to be assigned left */ + int nr_gp; /* number of GP counters used */ unsigned long used[BITS_TO_LONGS(X86_PMC_IDX_MAX)]; }; @@ -620,27 +635,29 @@ struct sched_state { struct perf_sched { int max_weight; int max_events; - struct perf_event **events; - struct sched_state state; + int max_gp; int saved_states; + struct event_constraint **constraints; + struct sched_state state; struct sched_state saved[SCHED_STATES_MAX]; }; /* * Initialize interator that runs through all events and counters. */ -static void perf_sched_init(struct perf_sched *sched, struct perf_event **events, - int num, int wmin, int wmax) +static void perf_sched_init(struct perf_sched *sched, struct event_constraint **constraints, + int num, int wmin, int wmax, int gpmax) { int idx; memset(sched, 0, sizeof(*sched)); sched->max_events = num; sched->max_weight = wmax; - sched->events = events; + sched->max_gp = gpmax; + sched->constraints = constraints; for (idx = 0; idx < num; idx++) { - if (events[idx]->hw.constraint->weight == wmin) + if (constraints[idx]->weight == wmin) break; } @@ -687,7 +704,7 @@ static bool __perf_sched_find_counter(struct perf_sched *sched) if (sched->state.event >= sched->max_events) return false; - c = sched->events[sched->state.event]->hw.constraint; + c = sched->constraints[sched->state.event]; /* Prefer fixed purpose counters */ if (c->idxmsk64 & (~0ULL << INTEL_PMC_IDX_FIXED)) { idx = INTEL_PMC_IDX_FIXED; @@ -696,11 +713,16 @@ static bool __perf_sched_find_counter(struct perf_sched *sched) goto done; } } + /* Grab the first unused counter starting with idx */ idx = sched->state.counter; for_each_set_bit_from(idx, c->idxmsk, INTEL_PMC_IDX_FIXED) { - if (!__test_and_set_bit(idx, sched->state.used)) + if (!__test_and_set_bit(idx, sched->state.used)) { + if (sched->state.nr_gp++ >= sched->max_gp) + return false; + goto done; + } } return false; @@ -745,7 +767,7 @@ static bool perf_sched_next_event(struct perf_sched *sched) if (sched->state.weight > sched->max_weight) return false; } - c = sched->events[sched->state.event]->hw.constraint; + c = sched->constraints[sched->state.event]; } while (c->weight != sched->state.weight); sched->state.counter = 0; /* start with first counter */ @@ -756,12 +778,12 @@ static bool perf_sched_next_event(struct perf_sched *sched) /* * Assign a counter for each event. */ -int perf_assign_events(struct perf_event **events, int n, - int wmin, int wmax, int *assign) +int perf_assign_events(struct event_constraint **constraints, int n, + int wmin, int wmax, int gpmax, int *assign) { struct perf_sched sched; - perf_sched_init(&sched, events, n, wmin, wmax); + perf_sched_init(&sched, constraints, n, wmin, wmax, gpmax); do { if (!perf_sched_find_counter(&sched)) @@ -788,9 +810,9 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign) x86_pmu.start_scheduling(cpuc); for (i = 0, wmin = X86_PMC_IDX_MAX, wmax = 0; i < n; i++) { - hwc = &cpuc->event_list[i]->hw; + cpuc->event_constraint[i] = NULL; c = x86_pmu.get_event_constraints(cpuc, i, cpuc->event_list[i]); - hwc->constraint = c; + cpuc->event_constraint[i] = c; wmin = min(wmin, c->weight); wmax = max(wmax, c->weight); @@ -801,7 +823,7 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign) */ for (i = 0; i < n; i++) { hwc = &cpuc->event_list[i]->hw; - c = hwc->constraint; + c = cpuc->event_constraint[i]; /* never assigned */ if (hwc->idx == -1) @@ -821,9 +843,26 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign) } /* slow path */ - if (i != n) - unsched = perf_assign_events(cpuc->event_list, n, wmin, - wmax, assign); + if (i != n) { + int gpmax = x86_pmu.num_counters; + + /* + * Do not allow scheduling of more than half the available + * generic counters. + * + * This helps avoid counter starvation of sibling thread by + * ensuring at most half the counters cannot be in exclusive + * mode. There is no designated counters for the limits. Any + * N/2 counters can be used. This helps with events with + * specific counter constraints. + */ + if (is_ht_workaround_enabled() && !cpuc->is_fake && + READ_ONCE(cpuc->excl_cntrs->exclusive_present)) + gpmax /= 2; + + unsched = perf_assign_events(cpuc->event_constraint, n, wmin, + wmax, gpmax, assign); + } /* * In case of success (unsched = 0), mark events as committed, @@ -840,7 +879,7 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign) e = cpuc->event_list[i]; e->hw.flags |= PERF_X86_EVENT_COMMITTED; if (x86_pmu.commit_scheduling) - x86_pmu.commit_scheduling(cpuc, e, assign[i]); + x86_pmu.commit_scheduling(cpuc, i, assign[i]); } } @@ -1292,8 +1331,10 @@ static void x86_pmu_del(struct perf_event *event, int flags) x86_pmu.put_event_constraints(cpuc, event); /* Delete the array entry. */ - while (++i < cpuc->n_events) + while (++i < cpuc->n_events) { cpuc->event_list[i-1] = cpuc->event_list[i]; + cpuc->event_constraint[i-1] = cpuc->event_constraint[i]; + } --cpuc->n_events; perf_event_update_userpage(event); diff --git a/arch/x86/kernel/cpu/perf_event.h b/arch/x86/kernel/cpu/perf_event.h index 6ac5cb7..ef78516 100644 --- a/arch/x86/kernel/cpu/perf_event.h +++ b/arch/x86/kernel/cpu/perf_event.h @@ -74,6 +74,7 @@ struct event_constraint { #define PERF_X86_EVENT_EXCL 0x0040 /* HT exclusivity on counter */ #define PERF_X86_EVENT_DYNAMIC 0x0080 /* dynamic alloc'd constraint */ #define PERF_X86_EVENT_RDPMC_ALLOWED 0x0100 /* grant rdpmc permission */ +#define PERF_X86_EVENT_EXCL_ACCT 0x0200 /* accounted EXCL event */ struct amd_nb { @@ -134,8 +135,6 @@ enum intel_excl_state_type { struct intel_excl_states { enum intel_excl_state_type init_state[X86_PMC_IDX_MAX]; enum intel_excl_state_type state[X86_PMC_IDX_MAX]; - int num_alloc_cntrs;/* #counters allocated */ - int max_alloc_cntrs;/* max #counters allowed */ bool sched_started; /* true if scheduling has started */ }; @@ -144,6 +143,11 @@ struct intel_excl_cntrs { struct intel_excl_states states[2]; + union { + u16 has_exclusive[2]; + u32 exclusive_present; + }; + int refcnt; /* per-core: #HT threads */ unsigned core_id; /* per-core: core id */ }; @@ -172,7 +176,11 @@ struct cpu_hw_events { added in the current transaction */ int assign[X86_PMC_IDX_MAX]; /* event to counter assignment */ u64 tags[X86_PMC_IDX_MAX]; + struct perf_event *event_list[X86_PMC_IDX_MAX]; /* in enabled order */ + struct event_constraint *event_constraint[X86_PMC_IDX_MAX]; + + int n_excl; /* the number of exclusive events */ unsigned int group_flag; int is_fake; @@ -519,9 +527,7 @@ struct x86_pmu { void (*put_event_constraints)(struct cpu_hw_events *cpuc, struct perf_event *event); - void (*commit_scheduling)(struct cpu_hw_events *cpuc, - struct perf_event *event, - int cntr); + void (*commit_scheduling)(struct cpu_hw_events *cpuc, int idx, int cntr); void (*start_scheduling)(struct cpu_hw_events *cpuc); @@ -717,8 +723,8 @@ static inline void __x86_pmu_enable_event(struct hw_perf_event *hwc, void x86_pmu_enable_all(int added); -int perf_assign_events(struct perf_event **events, int n, - int wmin, int wmax, int *assign); +int perf_assign_events(struct event_constraint **constraints, int n, + int wmin, int wmax, int gpmax, int *assign); int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign); void x86_pmu_stop(struct perf_event *event, int flags); @@ -929,4 +935,8 @@ static inline struct intel_shared_regs *allocate_shared_regs(int cpu) return NULL; } +static inline int is_ht_workaround_enabled(void) +{ + return 0; +} #endif /* CONFIG_CPU_SUP_INTEL */ diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 3998131..a1e35c9 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1923,7 +1923,6 @@ intel_start_scheduling(struct cpu_hw_events *cpuc) xl = &excl_cntrs->states[tid]; xl->sched_started = true; - xl->num_alloc_cntrs = 0; /* * lock shared state until we are done scheduling * in stop_event_scheduling() @@ -2000,6 +1999,11 @@ intel_get_excl_constraints(struct cpu_hw_events *cpuc, struct perf_event *event, * across HT threads */ is_excl = c->flags & PERF_X86_EVENT_EXCL; + if (is_excl && !(event->hw.flags & PERF_X86_EVENT_EXCL_ACCT)) { + event->hw.flags |= PERF_X86_EVENT_EXCL_ACCT; + if (!cpuc->n_excl++) + WRITE_ONCE(excl_cntrs->has_exclusive[tid], 1); + } /* * xl = state of current HT @@ -2008,18 +2012,6 @@ intel_get_excl_constraints(struct cpu_hw_events *cpuc, struct perf_event *event, xl = &excl_cntrs->states[tid]; xlo = &excl_cntrs->states[o_tid]; - /* - * do not allow scheduling of more than max_alloc_cntrs - * which is set to half the available generic counters. - * this helps avoid counter starvation of sibling thread - * by ensuring at most half the counters cannot be in - * exclusive mode. There is not designated counters for the - * limits. Any N/2 counters can be used. This helps with - * events with specifix counter constraints - */ - if (xl->num_alloc_cntrs++ == xl->max_alloc_cntrs) - return &emptyconstraint; - cx = c; /* @@ -2106,7 +2098,7 @@ static struct event_constraint * intel_get_event_constraints(struct cpu_hw_events *cpuc, int idx, struct perf_event *event) { - struct event_constraint *c1 = event->hw.constraint; + struct event_constraint *c1 = cpuc->event_constraint[idx]; struct event_constraint *c2; /* @@ -2150,6 +2142,11 @@ static void intel_put_excl_constraints(struct cpu_hw_events *cpuc, xl = &excl_cntrs->states[tid]; xlo = &excl_cntrs->states[o_tid]; + if (hwc->flags & PERF_X86_EVENT_EXCL_ACCT) { + hwc->flags &= ~PERF_X86_EVENT_EXCL_ACCT; + if (!--cpuc->n_excl) + WRITE_ONCE(excl_cntrs->has_exclusive[tid], 0); + } /* * put_constraint may be called from x86_schedule_events() @@ -2188,8 +2185,6 @@ intel_put_shared_regs_event_constraints(struct cpu_hw_events *cpuc, static void intel_put_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event) { - struct event_constraint *c = event->hw.constraint; - intel_put_shared_regs_event_constraints(cpuc, event); /* @@ -2197,19 +2192,14 @@ static void intel_put_event_constraints(struct cpu_hw_events *cpuc, * all events are subject to and must call the * put_excl_constraints() routine */ - if (c && cpuc->excl_cntrs) + if (cpuc->excl_cntrs) intel_put_excl_constraints(cpuc, event); - - /* cleanup dynamic constraint */ - if (c && (c->flags & PERF_X86_EVENT_DYNAMIC)) - event->hw.constraint = NULL; } -static void intel_commit_scheduling(struct cpu_hw_events *cpuc, - struct perf_event *event, int cntr) +static void intel_commit_scheduling(struct cpu_hw_events *cpuc, int idx, int cntr) { struct intel_excl_cntrs *excl_cntrs = cpuc->excl_cntrs; - struct event_constraint *c = event->hw.constraint; + struct event_constraint *c = cpuc->event_constraint[idx]; struct intel_excl_states *xlo, *xl; int tid = cpuc->excl_thread_id; int o_tid = 1 - tid; @@ -2639,8 +2629,6 @@ static void intel_pmu_cpu_starting(int cpu) cpuc->lbr_sel = &cpuc->shared_regs->regs[EXTRA_REG_LBR]; if (x86_pmu.flags & PMU_FL_EXCL_CNTRS) { - int h = x86_pmu.num_counters >> 1; - for_each_cpu(i, topology_thread_cpumask(cpu)) { struct intel_excl_cntrs *c; @@ -2654,11 +2642,6 @@ static void intel_pmu_cpu_starting(int cpu) } cpuc->excl_cntrs->core_id = core_id; cpuc->excl_cntrs->refcnt++; - /* - * set hard limit to half the number of generic counters - */ - cpuc->excl_cntrs->states[0].max_alloc_cntrs = h; - cpuc->excl_cntrs->states[1].max_alloc_cntrs = h; } } diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c index 813f75d..7f73b35 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_ds.c +++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c @@ -706,9 +706,9 @@ void intel_pmu_pebs_disable(struct perf_event *event) cpuc->pebs_enabled &= ~(1ULL << hwc->idx); - if (event->hw.constraint->flags & PERF_X86_EVENT_PEBS_LDLAT) + if (event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT) cpuc->pebs_enabled &= ~(1ULL << (hwc->idx + 32)); - else if (event->hw.constraint->flags & PERF_X86_EVENT_PEBS_ST) + else if (event->hw.flags & PERF_X86_EVENT_PEBS_ST) cpuc->pebs_enabled &= ~(1ULL << 63); if (cpuc->enabled) diff --git a/arch/x86/kernel/cpu/perf_event_intel_pt.c b/arch/x86/kernel/cpu/perf_event_intel_pt.c index ffe666c..123ff1b 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_pt.c +++ b/arch/x86/kernel/cpu/perf_event_intel_pt.c @@ -151,7 +151,7 @@ static int __init pt_pmu_hw_init(void) de_attr->attr.attr.name = pt_caps[i].name; - sysfs_attr_init(&de_attrs->attr.attr); + sysfs_attr_init(&de_attr->attr.attr); de_attr->attr.attr.mode = S_IRUGO; de_attr->attr.show = pt_cap_show; @@ -615,7 +615,8 @@ static int pt_buffer_reset_markers(struct pt_buffer *buf, struct perf_output_handle *handle) { - unsigned long idx, npages, end; + unsigned long head = local64_read(&buf->head); + unsigned long idx, npages, wakeup; if (buf->snapshot) return 0; @@ -634,17 +635,26 @@ static int pt_buffer_reset_markers(struct pt_buffer *buf, buf->topa_index[buf->stop_pos]->stop = 0; buf->topa_index[buf->intr_pos]->intr = 0; - if (pt_cap_get(PT_CAP_topa_multiple_entries)) { - npages = (handle->size + 1) >> PAGE_SHIFT; - end = (local64_read(&buf->head) >> PAGE_SHIFT) + npages; - /*if (end > handle->wakeup >> PAGE_SHIFT) - end = handle->wakeup >> PAGE_SHIFT;*/ - idx = end & (buf->nr_pages - 1); - buf->stop_pos = idx; - idx = (local64_read(&buf->head) >> PAGE_SHIFT) + npages - 1; - idx &= buf->nr_pages - 1; - buf->intr_pos = idx; - } + /* how many pages till the STOP marker */ + npages = handle->size >> PAGE_SHIFT; + + /* if it's on a page boundary, fill up one more page */ + if (!offset_in_page(head + handle->size + 1)) + npages++; + + idx = (head >> PAGE_SHIFT) + npages; + idx &= buf->nr_pages - 1; + buf->stop_pos = idx; + + wakeup = handle->wakeup >> PAGE_SHIFT; + + /* in the worst case, wake up the consumer one page before hard stop */ + idx = (head >> PAGE_SHIFT) + npages - 1; + if (idx > wakeup) + idx = wakeup; + + idx &= buf->nr_pages - 1; + buf->intr_pos = idx; buf->topa_index[buf->stop_pos]->stop = 1; buf->topa_index[buf->intr_pos]->intr = 1; diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c index c635b8b..dd319e5 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c @@ -365,9 +365,8 @@ static int uncore_assign_events(struct intel_uncore_box *box, int assign[], int bitmap_zero(used_mask, UNCORE_PMC_IDX_MAX); for (i = 0, wmin = UNCORE_PMC_IDX_MAX, wmax = 0; i < n; i++) { - hwc = &box->event_list[i]->hw; c = uncore_get_event_constraint(box, box->event_list[i]); - hwc->constraint = c; + box->event_constraint[i] = c; wmin = min(wmin, c->weight); wmax = max(wmax, c->weight); } @@ -375,7 +374,7 @@ static int uncore_assign_events(struct intel_uncore_box *box, int assign[], int /* fastpath, try to reuse previous register */ for (i = 0; i < n; i++) { hwc = &box->event_list[i]->hw; - c = hwc->constraint; + c = box->event_constraint[i]; /* never assigned */ if (hwc->idx == -1) @@ -395,8 +394,8 @@ static int uncore_assign_events(struct intel_uncore_box *box, int assign[], int } /* slow path */ if (i != n) - ret = perf_assign_events(box->event_list, n, - wmin, wmax, assign); + ret = perf_assign_events(box->event_constraint, n, + wmin, wmax, n, assign); if (!assign || ret) { for (i = 0; i < n; i++) diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.h b/arch/x86/kernel/cpu/perf_event_intel_uncore.h index 6c8c1e7..f789ec9 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.h +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.h @@ -97,6 +97,7 @@ struct intel_uncore_box { atomic_t refcnt; struct perf_event *events[UNCORE_PMC_IDX_MAX]; struct perf_event *event_list[UNCORE_PMC_IDX_MAX]; + struct event_constraint *event_constraint[UNCORE_PMC_IDX_MAX]; unsigned long active_mask[BITS_TO_LONGS(UNCORE_PMC_IDX_MAX)]; u64 tags[UNCORE_PMC_IDX_MAX]; struct pci_dev *pci_dev; |