diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/events/amd/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/events/amd/brs.c | 317 | ||||
| -rw-r--r-- | arch/x86/events/amd/core.c | 233 | ||||
| -rw-r--r-- | arch/x86/events/core.c | 10 | ||||
| -rw-r--r-- | arch/x86/events/perf_event.h | 101 | ||||
| -rw-r--r-- | arch/x86/include/asm/msr-index.h | 4 |
6 files changed, 645 insertions, 22 deletions
diff --git a/arch/x86/events/amd/Makefile b/arch/x86/events/amd/Makefile index 6cbe38d5fd9d..cf323ffab5cd 100644 --- a/arch/x86/events/amd/Makefile +++ b/arch/x86/events/amd/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_CPU_SUP_AMD) += core.o +obj-$(CONFIG_CPU_SUP_AMD) += core.o brs.o obj-$(CONFIG_PERF_EVENTS_AMD_POWER) += power.o obj-$(CONFIG_X86_LOCAL_APIC) += ibs.o obj-$(CONFIG_PERF_EVENTS_AMD_UNCORE) += amd-uncore.o diff --git a/arch/x86/events/amd/brs.c b/arch/x86/events/amd/brs.c new file mode 100644 index 000000000000..3c13c484c637 --- /dev/null +++ b/arch/x86/events/amd/brs.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Implement support for AMD Fam19h Branch Sampling feature + * Based on specifications published in AMD PPR Fam19 Model 01 + * + * Copyright 2021 Google LLC + * Contributed by Stephane Eranian <eranian@google.com> + */ +#include <linux/kernel.h> +#include <asm/msr.h> +#include <asm/cpufeature.h> + +#include "../perf_event.h" + +#define BRS_POISON 0xFFFFFFFFFFFFFFFEULL /* mark limit of valid entries */ + +/* Debug Extension Configuration register layout */ +union amd_debug_extn_cfg { + __u64 val; + struct { + __u64 rsvd0:2, /* reserved */ + brsmen:1, /* branch sample enable */ + rsvd4_3:2,/* reserved - must be 0x3 */ + vb:1, /* valid branches recorded */ + rsvd2:10, /* reserved */ + msroff:4, /* index of next entry to write */ + rsvd3:4, /* reserved */ + pmc:3, /* #PMC holding the sampling event */ + rsvd4:37; /* reserved */ + }; +}; + +static inline unsigned int brs_from(int idx) +{ + return MSR_AMD_SAMP_BR_FROM + 2 * idx; +} + +static inline unsigned int brs_to(int idx) +{ + return MSR_AMD_SAMP_BR_FROM + 2 * idx + 1; +} + +static inline void set_debug_extn_cfg(u64 val) +{ + /* bits[4:3] must always be set to 11b */ + wrmsrl(MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3); +} + +static inline u64 get_debug_extn_cfg(void) +{ + u64 val; + + rdmsrl(MSR_AMD_DBG_EXTN_CFG, val); + return val; +} + +static bool __init amd_brs_detect(void) +{ + if (!boot_cpu_has(X86_FEATURE_BRS)) + return false; + + switch (boot_cpu_data.x86) { + case 0x19: /* AMD Fam19h (Zen3) */ + x86_pmu.lbr_nr = 16; + + /* No hardware filtering supported */ + x86_pmu.lbr_sel_map = NULL; + x86_pmu.lbr_sel_mask = 0; + break; + default: + return false; + } + + return true; +} + +/* + * Current BRS implementation does not support branch type or privilege level + * filtering. Therefore, this function simply enforces these limitations. No need for + * a br_sel_map. Software filtering is not supported because it would not correlate well + * with a sampling period. + */ +int amd_brs_setup_filter(struct perf_event *event) +{ + u64 type = event->attr.branch_sample_type; + + /* No BRS support */ + if (!x86_pmu.lbr_nr) + return -EOPNOTSUPP; + + /* Can only capture all branches, i.e., no filtering */ + if ((type & ~PERF_SAMPLE_BRANCH_PLM_ALL) != PERF_SAMPLE_BRANCH_ANY) + return -EINVAL; + + /* can only capture at all priv levels due to the way BRS works */ + if ((type & PERF_SAMPLE_BRANCH_PLM_ALL) != PERF_SAMPLE_BRANCH_PLM_ALL) + return -EINVAL; + + return 0; +} + +/* tos = top of stack, i.e., last valid entry written */ +static inline int amd_brs_get_tos(union amd_debug_extn_cfg *cfg) +{ + /* + * msroff: index of next entry to write so top-of-stack is one off + * if BRS is full then msroff is set back to 0. + */ + return (cfg->msroff ? cfg->msroff : x86_pmu.lbr_nr) - 1; +} + +/* + * make sure we have a sane BRS offset to begin with + * especially with kexec + */ +void amd_brs_reset(void) +{ + /* + * Reset config + */ + set_debug_extn_cfg(0); + + /* + * Mark first entry as poisoned + */ + wrmsrl(brs_to(0), BRS_POISON); +} + +int __init amd_brs_init(void) +{ + if (!amd_brs_detect()) + return -EOPNOTSUPP; + + pr_cont("%d-deep BRS, ", x86_pmu.lbr_nr); + + return 0; +} + +void amd_brs_enable(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + union amd_debug_extn_cfg cfg; + + /* Activate only on first user */ + if (++cpuc->brs_active > 1) + return; + + cfg.val = 0; /* reset all fields */ + cfg.brsmen = 1; /* enable branch sampling */ + + /* Set enable bit */ + set_debug_extn_cfg(cfg.val); +} + +void amd_brs_enable_all(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + if (cpuc->lbr_users) + amd_brs_enable(); +} + +void amd_brs_disable(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + union amd_debug_extn_cfg cfg; + + /* Check if active (could be disabled via x86_pmu_disable_all()) */ + if (!cpuc->brs_active) + return; + + /* Only disable for last user */ + if (--cpuc->brs_active) + return; + + /* + * Clear the brsmen bit but preserve the others as they contain + * useful state such as vb and msroff + */ + cfg.val = get_debug_extn_cfg(); + + /* + * When coming in on interrupt and BRS is full, then hw will have + * already stopped BRS, no need to issue wrmsr again + */ + if (cfg.brsmen) { + cfg.brsmen = 0; + set_debug_extn_cfg(cfg.val); + } +} + +void amd_brs_disable_all(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + if (cpuc->lbr_users) + amd_brs_disable(); +} + +/* + * Caller must ensure amd_brs_inuse() is true before calling + * return: + */ +void amd_brs_drain(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + struct perf_event *event = cpuc->events[0]; + struct perf_branch_entry *br = cpuc->lbr_entries; + union amd_debug_extn_cfg cfg; + u32 i, nr = 0, num, tos, start; + u32 shift = 64 - boot_cpu_data.x86_virt_bits; + + /* + * BRS event forced on PMC0, + * so check if there is an event. + * It is possible to have lbr_users > 0 but the event + * not yet scheduled due to long latency PMU irq + */ + if (!event) + goto empty; + + cfg.val = get_debug_extn_cfg(); + + /* Sanity check [0-x86_pmu.lbr_nr] */ + if (WARN_ON_ONCE(cfg.msroff >= x86_pmu.lbr_nr)) + goto empty; + + /* No valid branch */ + if (cfg.vb == 0) + goto empty; + + /* + * msr.off points to next entry to be written + * tos = most recent entry index = msr.off - 1 + * BRS register buffer saturates, so we know we have + * start < tos and that we have to read from start to tos + */ + start = 0; + tos = amd_brs_get_tos(&cfg); + + num = tos - start + 1; + + /* + * BRS is only one pass (saturation) from MSROFF to depth-1 + * MSROFF wraps to zero when buffer is full + */ + for (i = 0; i < num; i++) { + u32 brs_idx = tos - i; + u64 from, to; + + rdmsrl(brs_to(brs_idx), to); + + /* Entry does not belong to us (as marked by kernel) */ + if (to == BRS_POISON) + break; + + rdmsrl(brs_from(brs_idx), from); + + /* + * Sign-extend SAMP_BR_TO to 64 bits, bits 61-63 are reserved. + * Necessary to generate proper virtual addresses suitable for + * symbolization + */ + to = (u64)(((s64)to << shift) >> shift); + + perf_clear_branch_entry_bitfields(br+nr); + + br[nr].from = from; + br[nr].to = to; + + nr++; + } +empty: + /* Record number of sampled branches */ + cpuc->lbr_stack.nr = nr; +} + +/* + * Poison most recent entry to prevent reuse by next task + * required because BRS entry are not tagged by PID + */ +static void amd_brs_poison_buffer(void) +{ + union amd_debug_extn_cfg cfg; + unsigned int idx; + + /* Get current state */ + cfg.val = get_debug_extn_cfg(); + + /* idx is most recently written entry */ + idx = amd_brs_get_tos(&cfg); + + /* Poison target of entry */ + wrmsrl(brs_to(idx), BRS_POISON); +} + +/* + * On context switch in, we need to make sure no samples from previous user + * are left in the BRS. + * + * On ctxswin, sched_in = true, called after the PMU has started + * On ctxswout, sched_in = false, called before the PMU is stopped + */ +void amd_pmu_brs_sched_task(struct perf_event_context *ctx, bool sched_in) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + + /* no active users */ + if (!cpuc->lbr_users) + return; + + /* + * On context switch in, we need to ensure we do not use entries + * from previous BRS user on that CPU, so we poison the buffer as + * a faster way compared to resetting all entries. + */ + if (sched_in) + amd_brs_poison_buffer(); +} diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c index 9687a8aef01c..c7ac70d8ed9a 100644 --- a/arch/x86/events/amd/core.c +++ b/arch/x86/events/amd/core.c @@ -325,8 +325,16 @@ static inline bool amd_is_pair_event_code(struct hw_perf_event *hwc) } } +#define AMD_FAM19H_BRS_EVENT 0xc4 /* RETIRED_TAKEN_BRANCH_INSTRUCTIONS */ +static inline int amd_is_brs_event(struct perf_event *e) +{ + return (e->hw.config & AMD64_RAW_EVENT_MASK) == AMD_FAM19H_BRS_EVENT; +} + static int amd_core_hw_config(struct perf_event *event) { + int ret = 0; + if (event->attr.exclude_host && event->attr.exclude_guest) /* * When HO == GO == 1 the hardware treats that as GO == HO == 0 @@ -343,7 +351,66 @@ static int amd_core_hw_config(struct perf_event *event) if ((x86_pmu.flags & PMU_FL_PAIR) && amd_is_pair_event_code(&event->hw)) event->hw.flags |= PERF_X86_EVENT_PAIR; - return 0; + /* + * if branch stack is requested + */ + if (has_branch_stack(event)) { + /* + * Due to interrupt holding, BRS is not recommended in + * counting mode. + */ + if (!is_sampling_event(event)) + return -EINVAL; + + /* + * Due to the way BRS operates by holding the interrupt until + * lbr_nr entries have been captured, it does not make sense + * to allow sampling on BRS with an event that does not match + * what BRS is capturing, i.e., retired taken branches. + * Otherwise the correlation with the event's period is even + * more loose: + * + * With retired taken branch: + * Effective P = P + 16 + X + * With any other event: + * Effective P = P + Y + X + * + * Where X is the number of taken branches due to interrupt + * skid. Skid is large. + * + * Where Y is the occurences of the event while BRS is + * capturing the lbr_nr entries. + * + * By using retired taken branches, we limit the impact on the + * Y variable. We know it cannot be more than the depth of + * BRS. + */ + if (!amd_is_brs_event(event)) + return -EINVAL; + + /* + * BRS implementation does not work with frequency mode + * reprogramming of the period. + */ + if (event->attr.freq) + return -EINVAL; + /* + * The kernel subtracts BRS depth from period, so it must + * be big enough. + */ + if (event->attr.sample_period <= x86_pmu.lbr_nr) + return -EINVAL; + + /* + * Check if we can allow PERF_SAMPLE_BRANCH_STACK + */ + ret = amd_brs_setup_filter(event); + + /* only set in case of success */ + if (!ret) + event->hw.flags |= PERF_X86_EVENT_AMD_BRS; + } + return ret; } static inline int amd_is_nb_event(struct hw_perf_event *hwc) @@ -366,7 +433,7 @@ static int amd_pmu_hw_config(struct perf_event *event) if (event->attr.precise_ip && get_ibs_caps()) return -ENOENT; - if (has_branch_stack(event)) + if (has_branch_stack(event) && !x86_pmu.lbr_nr) return -EOPNOTSUPP; ret = x86_pmu_hw_config(event); @@ -555,6 +622,8 @@ static void amd_pmu_cpu_starting(int cpu) cpuc->amd_nb->nb_id = nb_id; cpuc->amd_nb->refcnt++; + + amd_brs_reset(); } static void amd_pmu_cpu_dead(int cpu) @@ -610,6 +679,8 @@ static void amd_pmu_disable_all(void) struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); int idx; + amd_brs_disable_all(); + x86_pmu_disable_all(); /* @@ -634,6 +705,30 @@ static void amd_pmu_disable_all(void) } } +static void amd_pmu_enable_event(struct perf_event *event) +{ + x86_pmu_enable_event(event); +} + +static void amd_pmu_enable_all(int added) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + struct hw_perf_event *hwc; + int idx; + + amd_brs_enable_all(); + + for (idx = 0; idx < x86_pmu.num_counters; idx++) { + hwc = &cpuc->events[idx]->hw; + + /* only activate events which are marked as active */ + if (!test_bit(idx, cpuc->active_mask)) + continue; + + amd_pmu_enable_event(cpuc->events[idx]); + } +} + static void amd_pmu_disable_event(struct perf_event *event) { x86_pmu_disable_event(event); @@ -651,6 +746,18 @@ static void amd_pmu_disable_event(struct perf_event *event) amd_pmu_wait_on_overflow(event->hw.idx); } +static void amd_pmu_add_event(struct perf_event *event) +{ + if (needs_branch_stack(event)) + amd_pmu_brs_add(event); +} + +static void amd_pmu_del_event(struct perf_event *event) +{ + if (needs_branch_stack(event)) + amd_pmu_brs_del(event); +} + /* * Because of NMI latency, if multiple PMC counters are active or other sources * of NMIs are received, the perf NMI handler can handle one or more overflowed @@ -671,11 +778,31 @@ static void amd_pmu_disable_event(struct perf_event *event) */ static int amd_pmu_handle_irq(struct pt_regs *regs) { + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); int handled; + int pmu_enabled; + + /* + * Save the PMU state. + * It needs to be restored when leaving the handler. + */ + pmu_enabled = cpuc->enabled; + cpuc->enabled = 0; + + /* stop everything (includes BRS) */ + amd_pmu_disable_all(); + + /* Drain BRS is in use (could be inactive) */ + if (cpuc->lbr_users) + amd_brs_drain(); /* Process any counter overflows */ handled = x86_pmu_handle_irq(regs); + cpuc->enabled = pmu_enabled; + if (pmu_enabled) + amd_pmu_enable_all(0); + /* * If a counter was handled, record a timestamp such that un-handled * NMIs will be claimed if arriving within that window. @@ -897,6 +1024,51 @@ static void amd_put_event_constraints_f17h(struct cpu_hw_events *cpuc, --cpuc->n_pair; } +/* + * Because of the way BRS operates with an inactive and active phases, and + * the link to one counter, it is not possible to have two events using BRS + * scheduled at the same time. There would be an issue with enforcing the + * period of each one and given that the BRS saturates, it would not be possible + * to guarantee correlated content for all events. Therefore, in situations + * where multiple events want to use BRS, the kernel enforces mutual exclusion. + * Exclusion is enforced by chosing only one counter for events using BRS. + * The event scheduling logic will then automatically multiplex the + * events and ensure that at most one event is actively using BRS. + * + * The BRS counter could be any counter, but there is no constraint on Fam19h, + * therefore all counters are equal and thus we pick the first one: PMC0 + */ +static struct event_constraint amd_fam19h_brs_cntr0_constraint = + EVENT_CONSTRAINT(0, 0x1, AMD64_RAW_EVENT_MASK); + +static struct event_constraint amd_fam19h_brs_pair_cntr0_constraint = + __EVENT_CONSTRAINT(0, 0x1, AMD64_RAW_EVENT_MASK, 1, 0, PERF_X86_EVENT_PAIR); + +static struct event_constraint * +amd_get_event_constraints_f19h(struct cpu_hw_events *cpuc, int idx, + struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + bool has_brs = has_amd_brs(hwc); + + /* + * In case BRS is used with an event requiring a counter pair, + * the kernel allows it but only on counter 0 & 1 to enforce + * multiplexing requiring to protect BRS in case of multiple + * BRS users + */ + if (amd_is_pair_event_code(hwc)) { + return has_brs ? &amd_fam19h_brs_pair_cntr0_constraint + : &pair_constraint; + } + + if (has_brs) + return &amd_fam19h_brs_cntr0_constraint; + + return &unconstrained; +} + + static ssize_t amd_event_sysfs_show(char *page, u64 config) { u64 event = (config & ARCH_PERFMON_EVENTSEL_EVENT) | @@ -905,12 +1077,19 @@ static ssize_t amd_event_sysfs_show(char *page, u64 config) return x86_event_sysfs_show(page, config, event); } +static void amd_pmu_sched_task(struct perf_event_context *ctx, + bool sched_in) +{ + if (sched_in && x86_pmu.lbr_nr) + amd_pmu_brs_sched_task(ctx, sched_in); +} + static __initconst const struct x86_pmu amd_pmu = { .name = "AMD", .handle_irq = amd_pmu_handle_irq, .disable_all = amd_pmu_disable_all, - .enable_all = x86_pmu_enable_all, - .enable = x86_pmu_enable_event, + .enable_all = amd_pmu_enable_all, + .enable = amd_pmu_enable_event, .disable = amd_pmu_disable_event, .hw_config = amd_pmu_hw_config, .schedule_events = x86_schedule_events, @@ -920,6 +1099,8 @@ static __initconst const struct x86_pmu amd_pmu = { .event_map = amd_pmu_event_map, .max_events = ARRAY_SIZE(amd_perfmon_event_map), .num_counters = AMD64_NUM_COUNTERS, + .add = amd_pmu_add_event, + .del = amd_pmu_del_event, .cntval_bits = 48, .cntval_mask = (1ULL << 48) - 1, .apic = 1, @@ -938,6 +1119,37 @@ static __initconst const struct x86_pmu amd_pmu = { .amd_nb_constraints = 1, }; +static ssize_t branches_show(struct device *cdev, + struct device_attribute *attr, + char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%d\n", x86_pmu.lbr_nr); +} + +static DEVICE_ATTR_RO(branches); + +static struct attribute *amd_pmu_brs_attrs[] = { + &dev_attr_branches.attr, + NULL, +}; + +static umode_t +amd_brs_is_visible(struct kobject *kobj, struct attribute *attr, int i) +{ + return x86_pmu.lbr_nr ? attr->mode : 0; +} + +static struct attribute_group group_caps_amd_brs = { + .name = "caps", + .attrs = amd_pmu_brs_attrs, + .is_visible = amd_brs_is_visible, +}; + +static const struct attribute_group *amd_attr_update[] = { + &group_caps_amd_brs, + NULL, +}; + static int __init amd_core_pmu_init(void) { u64 even_ctr_mask = 0ULL; @@ -989,6 +1201,19 @@ static int __init amd_core_pmu_init(void) x86_pmu.flags |= PMU_FL_PAIR; } + /* + * BRS requires special event constraints and flushing on ctxsw. + */ + if (boot_cpu_data.x86 >= 0x19 && !amd_brs_init()) { + x86_pmu.get_event_constraints = amd_get_event_constraints_f19h; + x86_pmu.sched_task = amd_pmu_sched_task; + /* + * put_event_constraints callback same as Fam17h, set above + */ + } + + x86_pmu.attr_update = amd_attr_update; + pr_cont("core perfctr, "); return 0; } diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index eef816fc216d..7ada9172b074 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -1338,6 +1338,10 @@ static void x86_pmu_enable(struct pmu *pmu) if (hwc->state & PERF_HES_ARCH) continue; + /* + * if cpuc->enabled = 0, then no wrmsr as + * per x86_pmu_enable_event() + */ x86_pmu_start(event, PERF_EF_RELOAD); } cpuc->n_added = 0; @@ -1704,11 +1708,15 @@ int x86_pmu_handle_irq(struct pt_regs *regs) * event overflow */ handled++; - perf_sample_data_init(&data, 0, event->hw.last_period); if (!x86_perf_event_set_period(event)) continue; + perf_sample_data_init(&data, 0, event->hw.last_period); + + if (has_branch_stack(event)) + data.br_stack = &cpuc->lbr_stack; + if (perf_event_overflow(event, &data, regs)) x86_pmu_stop(event, 0); } diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index 150261d929b9..6f1265163c9f 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -67,22 +67,23 @@ static inline bool constraint_match(struct event_constraint *c, u64 ecode) /* * struct hw_perf_event.flags flags */ -#define PERF_X86_EVENT_PEBS_LDLAT 0x0001 /* ld+ldlat data address sampling */ -#define PERF_X86_EVENT_PEBS_ST 0x0002 /* st data address sampling */ -#define PERF_X86_EVENT_PEBS_ST_HSW 0x0004 /* haswell style datala, store */ -#define PERF_X86_EVENT_PEBS_LD_HSW 0x0008 /* haswell style datala, load */ -#define PERF_X86_EVENT_PEBS_NA_HSW 0x0010 /* haswell style datala, unknown */ -#define PERF_X86_EVENT_EXCL 0x0020 /* HT exclusivity on counter */ -#define PERF_X86_EVENT_DYNAMIC 0x0040 /* dynamic alloc'd constraint */ - -#define PERF_X86_EVENT_EXCL_ACCT 0x0100 /* accounted EXCL event */ -#define PERF_X86_EVENT_AUTO_RELOAD 0x0200 /* use PEBS auto-reload */ -#define PERF_X86_EVENT_LARGE_PEBS 0x0400 /* use large PEBS */ -#define PERF_X86_EVENT_PEBS_VIA_PT 0x0800 /* use PT buffer for PEBS */ -#define PERF_X86_EVENT_PAIR 0x1000 /* Large Increment per Cycle */ -#define PERF_X86_EVENT_LBR_SELECT 0x2000 /* Save/Restore MSR_LBR_SELECT */ -#define PERF_X86_EVENT_TOPDOWN 0x4000 /* Count Topdown slots/metrics events */ -#define PERF_X86_EVENT_PEBS_STLAT 0x8000 /* st+stlat data address sampling */ +#define PERF_X86_EVENT_PEBS_LDLAT 0x00001 /* ld+ldlat data address sampling */ +#define PERF_X86_EVENT_PEBS_ST 0x00002 /* st data address sampling */ +#define PERF_X86_EVENT_PEBS_ST_HSW 0x00004 /* haswell style datala, store */ +#define PERF_X86_EVENT_PEBS_LD_HSW 0x00008 /* haswell style datala, load */ +#define PERF_X86_EVENT_PEBS_NA_HSW 0x00010 /* haswell style datala, unknown */ +#define PERF_X86_EVENT_EXCL 0x00020 /* HT exclusivity on counter */ +#define PERF_X86_EVENT_DYNAMIC 0x00040 /* dynamic alloc'd constraint */ + +#define PERF_X86_EVENT_EXCL_ACCT 0x00100 /* accounted EXCL event */ +#define PERF_X86_EVENT_AUTO_RELOAD 0x00200 /* use PEBS auto-reload */ +#define PERF_X86_EVENT_LARGE_PEBS 0x00400 /* use large PEBS */ +#define PERF_X86_EVENT_PEBS_VIA_PT 0x00800 /* use PT buffer for PEBS */ +#define PERF_X86_EVENT_PAIR 0x01000 /* Large Increment per Cycle */ +#define PERF_X86_EVENT_LBR_SELECT 0x02000 /* Save/Restore MSR_LBR_SELECT */ +#define PERF_X86_EVENT_TOPDOWN 0x04000 /* Count Topdown slots/metrics events */ +#define PERF_X86_EVENT_PEBS_STLAT 0x08000 /* st+stlat data address sampling */ +#define PERF_X86_EVENT_AMD_BRS 0x10000 /* AMD Branch Sampling */ static inline bool is_topdown_count(struct perf_event *event) { @@ -325,6 +326,8 @@ struct cpu_hw_events { * AMD specific bits */ struct amd_nb *amd_nb; + int brs_active; /* BRS is enabled */ + /* Inverted mask of bits to clear in the perf_ctr ctrl registers */ u64 perf_ctr_virt_mask; int n_pair; /* Large increment events */ @@ -1105,6 +1108,11 @@ int x86_pmu_hw_config(struct perf_event *event); void x86_pmu_disable_all(void); +static inline bool has_amd_brs(struct hw_perf_event *hwc) +{ + return hwc->flags & PERF_X86_EVENT_AMD_BRS; +} + static inline bool is_counter_pair(struct hw_perf_event *hwc) { return hwc->flags & PERF_X86_EVENT_PAIR; @@ -1210,6 +1218,50 @@ static inline bool fixed_counter_disabled(int i, struct pmu *pmu) #ifdef CONFIG_CPU_SUP_AMD int amd_pmu_init(void); +int amd_brs_init(void); +void amd_brs_disable(void); +void amd_brs_enable(void); +void amd_brs_enable_all(void); +void amd_brs_disable_all(void); +void amd_brs_drain(void); +void amd_brs_disable_all(void); +int amd_brs_setup_filter(struct perf_event *event); +void amd_brs_reset(void); + +static inline void amd_pmu_brs_add(struct perf_event *event) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + + perf_sched_cb_inc(event->ctx->pmu); + cpuc->lbr_users++; + /* + * No need to reset BRS because it is reset + * on brs_enable() and it is saturating + */ +} + +static inline void amd_pmu_brs_del(struct perf_event *event) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + + cpuc->lbr_users--; + WARN_ON_ONCE(cpuc->lbr_users < 0); + + perf_sched_cb_dec(event->ctx->pmu); +} + +void amd_pmu_brs_sched_task(struct perf_event_context *ctx, bool sched_in); + +/* + * check if BRS is activated on the CPU + * active defined as it has non-zero users and DBG_EXT_CFG.BRSEN=1 + */ +static inline bool amd_brs_active(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + + return cpuc->brs_active; +} #else /* CONFIG_CPU_SUP_AMD */ @@ -1218,6 +1270,23 @@ static inline int amd_pmu_init(void) return 0; } +static inline int amd_brs_init(void) +{ + return -EOPNOTSUPP; +} + +static inline void amd_brs_drain(void) +{ +} + +static inline void amd_brs_enable_all(void) +{ +} + +static inline void amd_brs_disable_all(void) +{ +} + #endif /* CONFIG_CPU_SUP_AMD */ static inline int is_pebs_pt(struct perf_event *event) diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 0eb90d21049e..8179ea351bd8 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -688,6 +688,10 @@ #define MSR_IA32_PERF_CTL 0x00000199 #define INTEL_PERF_CTL_MASK 0xffff +/* AMD Branch Sampling configuration */ +#define MSR_AMD_DBG_EXTN_CFG 0xc000010f +#define MSR_AMD_SAMP_BR_FROM 0xc0010300 + #define MSR_IA32_MPERF 0x000000e7 #define MSR_IA32_APERF 0x000000e8 |