diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-05-26 15:40:23 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-05-26 15:40:23 -0700 |
| commit | ddddf9d64f7361323da663637adb4a02466bfc99 (patch) | |
| tree | 5fa3fc48db5d0ed98d0386754cf435fc6cd67cbb | |
| parent | eaed94d1f68c3476834e07409f5fc9bd8efd6395 (diff) | |
| parent | e7d952cc39fca34386ec9f15f68cb2eaac01b5ae (diff) | |
| download | linux-ddddf9d64f7361323da663637adb4a02466bfc99.tar.gz linux-ddddf9d64f7361323da663637adb4a02466bfc99.tar.bz2 linux-ddddf9d64f7361323da663637adb4a02466bfc99.zip | |
Merge tag 'perf-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events updates from Ingo Molnar:
"Core & generic-arch updates:
- Add support for dynamic constraints and propagate it to the Intel
driver (Kan Liang)
- Fix & enhance driver-specific throttling support (Kan Liang)
- Record sample last_period before updating on the x86 and PowerPC
platforms (Mark Barnett)
- Make perf_pmu_unregister() usable (Peter Zijlstra)
- Unify perf_event_free_task() / perf_event_exit_task_context()
(Peter Zijlstra)
- Simplify perf_event_release_kernel() and perf_event_free_task()
(Peter Zijlstra)
- Allocate non-contiguous AUX pages by default (Yabin Cui)
Uprobes updates:
- Add support to emulate NOP instructions (Jiri Olsa)
- selftests/bpf: Add 5-byte NOP uprobe trigger benchmark (Jiri Olsa)
x86 Intel PMU enhancements:
- Support Intel Auto Counter Reload [ACR] (Kan Liang)
- Add PMU support for Clearwater Forest (Dapeng Mi)
- Arch-PEBS preparatory changes: (Dapeng Mi)
- Parse CPUID archPerfmonExt leaves for non-hybrid CPUs
- Decouple BTS initialization from PEBS initialization
- Introduce pairs of PEBS static calls
x86 AMD PMU enhancements:
- Use hrtimer for handling overflows in the AMD uncore driver
(Sandipan Das)
- Prevent UMC counters from saturating (Sandipan Das)
Fixes and cleanups:
- Fix put_ctx() ordering (Frederic Weisbecker)
- Fix irq work dereferencing garbage (Frederic Weisbecker)
- Misc fixes and cleanups (Changbin Du, Frederic Weisbecker, Ian
Rogers, Ingo Molnar, Kan Liang, Peter Zijlstra, Qing Wang, Sandipan
Das, Thorsten Blum)"
* tag 'perf-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
perf/headers: Clean up <linux/perf_event.h> a bit
perf/uapi: Clean up <uapi/linux/perf_event.h> a bit
perf/uapi: Fix PERF_RECORD_SAMPLE comments in <uapi/linux/perf_event.h>
mips/perf: Remove driver-specific throttle support
xtensa/perf: Remove driver-specific throttle support
sparc/perf: Remove driver-specific throttle support
loongarch/perf: Remove driver-specific throttle support
csky/perf: Remove driver-specific throttle support
arc/perf: Remove driver-specific throttle support
alpha/perf: Remove driver-specific throttle support
perf/apple_m1: Remove driver-specific throttle support
perf/arm: Remove driver-specific throttle support
s390/perf: Remove driver-specific throttle support
powerpc/perf: Remove driver-specific throttle support
perf/x86/zhaoxin: Remove driver-specific throttle support
perf/x86/amd: Remove driver-specific throttle support
perf/x86/intel: Remove driver-specific throttle support
perf: Only dump the throttle log for the leader
perf: Fix the throttle logic for a group
perf/core: Add the is_event_in_freq_mode() helper to simplify the code
...
44 files changed, 1996 insertions, 1210 deletions
diff --git a/arch/alpha/kernel/perf_event.c b/arch/alpha/kernel/perf_event.c index 1f0eb4f25c0f..a3eaab094ece 100644 --- a/arch/alpha/kernel/perf_event.c +++ b/arch/alpha/kernel/perf_event.c @@ -852,14 +852,9 @@ static void alpha_perf_event_irq_handler(unsigned long la_ptr, alpha_perf_event_update(event, hwc, idx, alpha_pmu->pmc_max_period[idx]+1); perf_sample_data_init(&data, 0, hwc->last_period); - if (alpha_perf_event_set_period(event, hwc, idx)) { - if (perf_event_overflow(event, &data, regs)) { - /* Interrupts coming too quickly; "throttle" the - * counter, i.e., disable it for a little while. - */ - alpha_pmu_stop(event, 0); - } - } + if (alpha_perf_event_set_period(event, hwc, idx)) + perf_event_overflow(event, &data, regs); + wrperfmon(PERFMON_CMD_ENABLE, cpuc->idx_mask); return; diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c index 6e5a651cd75c..ed6d4f0cd621 100644 --- a/arch/arc/kernel/perf_event.c +++ b/arch/arc/kernel/perf_event.c @@ -599,10 +599,8 @@ static irqreturn_t arc_pmu_intr(int irq, void *dev) arc_perf_event_update(event, &event->hw, event->hw.idx); perf_sample_data_init(&data, 0, hwc->last_period); - if (arc_pmu_event_set_period(event)) { - if (perf_event_overflow(event, &data, regs)) - arc_pmu_stop(event, 0); - } + if (arc_pmu_event_set_period(event)) + perf_event_overflow(event, &data, regs); active_ints &= ~BIT(idx); } while (active_ints); diff --git a/arch/csky/kernel/perf_event.c b/arch/csky/kernel/perf_event.c index e5f18420ce64..e0a36acd265b 100644 --- a/arch/csky/kernel/perf_event.c +++ b/arch/csky/kernel/perf_event.c @@ -1139,8 +1139,7 @@ static irqreturn_t csky_pmu_handle_irq(int irq_num, void *dev) perf_sample_data_init(&data, 0, hwc->last_period); csky_pmu_event_set_period(event); - if (perf_event_overflow(event, &data, regs)) - csky_pmu_stop_event(event); + perf_event_overflow(event, &data, regs); } csky_pmu_enable(&csky_pmu.pmu); diff --git a/arch/loongarch/kernel/perf_event.c b/arch/loongarch/kernel/perf_event.c index f86a4b838dd7..8ad098703488 100644 --- a/arch/loongarch/kernel/perf_event.c +++ b/arch/loongarch/kernel/perf_event.c @@ -479,8 +479,7 @@ static void handle_associated_event(struct cpu_hw_events *cpuc, int idx, if (!loongarch_pmu_event_set_period(event, hwc, idx)) return; - if (perf_event_overflow(event, data, regs)) - loongarch_pmu_disable_event(idx); + perf_event_overflow(event, data, regs); } static irqreturn_t pmu_handle_irq(int irq, void *dev) diff --git a/arch/mips/kernel/perf_event_mipsxx.c b/arch/mips/kernel/perf_event_mipsxx.c index c4d6b09136b1..196a070349b0 100644 --- a/arch/mips/kernel/perf_event_mipsxx.c +++ b/arch/mips/kernel/perf_event_mipsxx.c @@ -791,8 +791,7 @@ static void handle_associated_event(struct cpu_hw_events *cpuc, if (!mipspmu_event_set_period(event, hwc, idx)) return; - if (perf_event_overflow(event, data, regs)) - mipsxx_pmu_disable_event(idx); + perf_event_overflow(event, data, regs); } diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index b906d28f74fd..8b0081441f85 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -2239,6 +2239,7 @@ static void record_and_restart(struct perf_event *event, unsigned long val, struct pt_regs *regs) { u64 period = event->hw.sample_period; + const u64 last_period = event->hw.last_period; s64 prev, delta, left; int record = 0; @@ -2320,7 +2321,7 @@ static void record_and_restart(struct perf_event *event, unsigned long val, if (record) { struct perf_sample_data data; - perf_sample_data_init(&data, ~0ULL, event->hw.last_period); + perf_sample_data_init(&data, ~0ULL, last_period); if (event->attr.sample_type & PERF_SAMPLE_ADDR_TYPE) perf_get_data_addr(event, regs, &data.addr); @@ -2343,12 +2344,10 @@ static void record_and_restart(struct perf_event *event, unsigned long val, ppmu->get_mem_weight(&data.weight.full, event->attr.sample_type); data.sample_flags |= PERF_SAMPLE_WEIGHT_TYPE; } - if (perf_event_overflow(event, &data, regs)) - power_pmu_stop(event, 0); + perf_event_overflow(event, &data, regs); } else if (period) { /* Account for interrupt in case of invalid SIAR */ - if (perf_event_account_interrupt(event)) - power_pmu_stop(event, 0); + perf_event_account_interrupt(event); } } diff --git a/arch/powerpc/perf/core-fsl-emb.c b/arch/powerpc/perf/core-fsl-emb.c index 1a53ab08447c..7120ab20cbfe 100644 --- a/arch/powerpc/perf/core-fsl-emb.c +++ b/arch/powerpc/perf/core-fsl-emb.c @@ -590,6 +590,7 @@ static void record_and_restart(struct perf_event *event, unsigned long val, struct pt_regs *regs) { u64 period = event->hw.sample_period; + const u64 last_period = event->hw.last_period; s64 prev, delta, left; int record = 0; @@ -632,10 +633,9 @@ static void record_and_restart(struct perf_event *event, unsigned long val, if (record) { struct perf_sample_data data; - perf_sample_data_init(&data, 0, event->hw.last_period); + perf_sample_data_init(&data, 0, last_period); - if (perf_event_overflow(event, &data, regs)) - fsl_emb_pmu_stop(event, 0); + perf_event_overflow(event, &data, regs); } } diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c index e657fad7e376..6a262e198e35 100644 --- a/arch/s390/kernel/perf_cpum_cf.c +++ b/arch/s390/kernel/perf_cpum_cf.c @@ -980,8 +980,6 @@ static int cfdiag_push_sample(struct perf_event *event, } overflow = perf_event_overflow(event, &data, ®s); - if (overflow) - event->pmu->stop(event, 0); perf_event_update_userpage(event); return overflow; diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c index ad22799d8a7d..91469401f2c9 100644 --- a/arch/s390/kernel/perf_cpum_sf.c +++ b/arch/s390/kernel/perf_cpum_sf.c @@ -1072,10 +1072,7 @@ static int perf_push_sample(struct perf_event *event, overflow = 0; if (perf_event_exclude(event, ®s, sde_regs)) goto out; - if (perf_event_overflow(event, &data, ®s)) { - overflow = 1; - event->pmu->stop(event, 0); - } + overflow = perf_event_overflow(event, &data, ®s); perf_event_update_userpage(event); out: return overflow; diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c index f02a283a8e8f..cae4d33002a5 100644 --- a/arch/sparc/kernel/perf_event.c +++ b/arch/sparc/kernel/perf_event.c @@ -1668,8 +1668,7 @@ static int __kprobes perf_event_nmi_handler(struct notifier_block *self, if (!sparc_perf_event_set_period(event, hwc, idx)) continue; - if (perf_event_overflow(event, &data, regs)) - sparc_pmu_stop(event, 0); + perf_event_overflow(event, &data, regs); } finish_clock = sched_clock(); diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c index 30d6ceb4c8ad..5e64283b9bf2 100644 --- a/arch/x86/events/amd/core.c +++ b/arch/x86/events/amd/core.c @@ -1003,8 +1003,7 @@ static int amd_pmu_v2_handle_irq(struct pt_regs *regs) perf_sample_save_brstack(&data, event, &cpuc->lbr_stack, NULL); - if (perf_event_overflow(event, &data, regs)) - x86_pmu_stop(event, 0); + perf_event_overflow(event, &data, regs); } /* diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c index 0252b7ea8bca..4bbbca02aeb1 100644 --- a/arch/x86/events/amd/ibs.c +++ b/arch/x86/events/amd/ibs.c @@ -1373,9 +1373,7 @@ fail: hwc->sample_period = perf_ibs->min_period; out: - if (throttle) { - perf_ibs_stop(event, 0); - } else { + if (!throttle) { if (perf_ibs == &perf_ibs_op) { if (ibs_caps & IBS_CAPS_OPCNTEXT) { new_config = period & IBS_OP_MAX_CNT_EXT_MASK; diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c index 49c26ce2b115..d328de166481 100644 --- a/arch/x86/events/amd/uncore.c +++ b/arch/x86/events/amd/uncore.c @@ -21,6 +21,7 @@ #define NUM_COUNTERS_NB 4 #define NUM_COUNTERS_L2 4 #define NUM_COUNTERS_L3 6 +#define NUM_COUNTERS_MAX 64 #define RDPMC_BASE_NB 6 #define RDPMC_BASE_LLC 10 @@ -38,7 +39,10 @@ struct amd_uncore_ctx { int refcnt; int cpu; struct perf_event **events; - struct hlist_node node; + unsigned long active_mask[BITS_TO_LONGS(NUM_COUNTERS_MAX)]; + int nr_active; + struct hrtimer hrtimer; + u64 hrtimer_duration; }; struct amd_uncore_pmu { @@ -83,11 +87,51 @@ struct amd_uncore { static struct amd_uncore uncores[UNCORE_TYPE_MAX]; +/* Interval for hrtimer, defaults to 60000 milliseconds */ +static unsigned int update_interval = 60 * MSEC_PER_SEC; +module_param(update_interval, uint, 0444); + static struct amd_uncore_pmu *event_to_amd_uncore_pmu(struct perf_event *event) { return container_of(event->pmu, struct amd_uncore_pmu, pmu); } +static enum hrtimer_restart amd_uncore_hrtimer(struct hrtimer *hrtimer) +{ + struct amd_uncore_ctx *ctx; + struct perf_event *event; + int bit; + + ctx = container_of(hrtimer, struct amd_uncore_ctx, hrtimer); + + if (!ctx->nr_active || ctx->cpu != smp_processor_id()) + return HRTIMER_NORESTART; + + for_each_set_bit(bit, ctx->active_mask, NUM_COUNTERS_MAX) { + event = ctx->events[bit]; + event->pmu->read(event); + } + + hrtimer_forward_now(hrtimer, ns_to_ktime(ctx->hrtimer_duration)); + return HRTIMER_RESTART; +} + +static void amd_uncore_start_hrtimer(struct amd_uncore_ctx *ctx) +{ + hrtimer_start(&ctx->hrtimer, ns_to_ktime(ctx->hrtimer_duration), + HRTIMER_MODE_REL_PINNED_HARD); +} + +static void amd_uncore_cancel_hrtimer(struct amd_uncore_ctx *ctx) +{ + hrtimer_cancel(&ctx->hrtimer); +} + +static void amd_uncore_init_hrtimer(struct amd_uncore_ctx *ctx) +{ + hrtimer_setup(&ctx->hrtimer, amd_uncore_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); +} + static void amd_uncore_read(struct perf_event *event) { struct hw_perf_event *hwc = &event->hw; @@ -118,18 +162,26 @@ static void amd_uncore_read(struct perf_event *event) static void amd_uncore_start(struct perf_event *event, int flags) { + struct amd_uncore_pmu *pmu = event_to_amd_uncore_pmu(event); + struct amd_uncore_ctx *ctx = *per_cpu_ptr(pmu->ctx, event->cpu); struct hw_perf_event *hwc = &event->hw; + if (!ctx->nr_active++) + amd_uncore_start_hrtimer(ctx); + if (flags & PERF_EF_RELOAD) wrmsrl(hwc->event_base, (u64)local64_read(&hwc->prev_count)); hwc->state = 0; + __set_bit(hwc->idx, ctx->active_mask); wrmsrl(hwc->config_base, (hwc->config | ARCH_PERFMON_EVENTSEL_ENABLE)); perf_event_update_userpage(event); } static void amd_uncore_stop(struct perf_event *event, int flags) { + struct amd_uncore_pmu *pmu = event_to_amd_uncore_pmu(event); + struct amd_uncore_ctx *ctx = *per_cpu_ptr(pmu->ctx, event->cpu); struct hw_perf_event *hwc = &event->hw; wrmsrl(hwc->config_base, hwc->config); @@ -139,6 +191,11 @@ static void amd_uncore_stop(struct perf_event *event, int flags) event->pmu->read(event); hwc->state |= PERF_HES_UPTODATE; } + + if (!--ctx->nr_active) + amd_uncore_cancel_hrtimer(ctx); + + __clear_bit(hwc->idx, ctx->active_mask); } static int amd_uncore_add(struct perf_event *event, int flags) @@ -491,6 +548,9 @@ static int amd_uncore_ctx_init(struct amd_uncore *uncore, unsigned int cpu) goto fail; } + amd_uncore_init_hrtimer(curr); + curr->hrtimer_duration = (u64)update_interval * NSEC_PER_MSEC; + cpumask_set_cpu(cpu, &pmu->active_mask); } @@ -880,16 +940,55 @@ static int amd_uncore_umc_event_init(struct perf_event *event) static void amd_uncore_umc_start(struct perf_event *event, int flags) { + struct amd_uncore_pmu *pmu = event_to_amd_uncore_pmu(event); + struct amd_uncore_ctx *ctx = *per_cpu_ptr(pmu->ctx, event->cpu); struct hw_perf_event *hwc = &event->hw; + if (!ctx->nr_active++) + amd_uncore_start_hrtimer(ctx); + if (flags & PERF_EF_RELOAD) wrmsrl(hwc->event_base, (u64)local64_read(&hwc->prev_count)); hwc->state = 0; + __set_bit(hwc->idx, ctx->active_mask); wrmsrl(hwc->config_base, (hwc->config | AMD64_PERFMON_V2_ENABLE_UMC)); perf_event_update_userpage(event); } +static void amd_uncore_umc_read(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + u64 prev, new, shift; + s64 delta; + + shift = COUNTER_SHIFT + 1; + prev = local64_read(&hwc->prev_count); + + /* + * UMC counters do not have RDPMC assignments. Read counts directly + * from the corresponding PERF_CTR. + */ + rdmsrl(hwc->event_base, new); + + /* + * Unlike the other uncore counters, UMC counters saturate and set the + * Overflow bit (bit 48) on overflow. Since they do not roll over, + * proactively reset the corresponding PERF_CTR when bit 47 is set so + * that the counter never gets a chance to saturate. + */ + if (new & BIT_ULL(63 - COUNTER_SHIFT)) { + wrmsrl(hwc->event_base, 0); + local64_set(&hwc->prev_count, 0); + } else { + local64_set(&hwc->prev_count, new); + } + + delta = (new << shift) - (prev << shift); + delta >>= shift; + local64_add(delta, &event->count); +} + static void amd_uncore_umc_ctx_scan(struct amd_uncore *uncore, unsigned int cpu) { @@ -968,7 +1067,7 @@ int amd_uncore_umc_ctx_init(struct amd_uncore *uncore, unsigned int cpu) .del = amd_uncore_del, .start = amd_uncore_umc_start, .stop = amd_uncore_stop, - .read = amd_uncore_read, + .read = amd_uncore_umc_read, .capabilities = PERF_PMU_CAP_NO_EXCLUDE | PERF_PMU_CAP_NO_INTERRUPT, .module = THIS_MODULE, }; diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 139ad80d1df3..4c49eef8052e 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -95,6 +95,11 @@ DEFINE_STATIC_CALL_NULL(x86_pmu_filter, *x86_pmu.filter); DEFINE_STATIC_CALL_NULL(x86_pmu_late_setup, *x86_pmu.late_setup); +DEFINE_STATIC_CALL_NULL(x86_pmu_pebs_enable, *x86_pmu.pebs_enable); +DEFINE_STATIC_CALL_NULL(x86_pmu_pebs_disable, *x86_pmu.pebs_disable); +DEFINE_STATIC_CALL_NULL(x86_pmu_pebs_enable_all, *x86_pmu.pebs_enable_all); +DEFINE_STATIC_CALL_NULL(x86_pmu_pebs_disable_all, *x86_pmu.pebs_disable_all); + /* * This one is magic, it will get called even when PMU init fails (because * there is no PMU), in which case it should simply return NULL. @@ -674,6 +679,7 @@ static int __x86_pmu_event_init(struct perf_event *event) event->hw.idx = -1; event->hw.last_cpu = -1; event->hw.last_tag = ~0ULL; + event->hw.dyn_constraint = ~0ULL; /* mark unused */ event->hw.extra_reg.idx = EXTRA_REG_NONE; @@ -756,15 +762,16 @@ void x86_pmu_enable_all(int added) int is_x86_event(struct perf_event *event) { - int i; - - if (!is_hybrid()) - return event->pmu == &pmu; - - for (i = 0; i < x86_pmu.num_hybrid_pmus; i++) { - if (event->pmu == &x86_pmu.hybrid_pmu[i].pmu) - return true; - } + /* + * For a non-hybrid platforms, the type of X86 pmu is + * always PERF_TYPE_RAW. + * For a hybrid platform, the PERF_PMU_CAP_EXTENDED_HW_TYPE + * is a unique capability for the X86 PMU. + * Use them to detect a X86 event. + */ + if (event->pmu->type == PERF_TYPE_RAW || + event->pmu->capabilities & PERF_PMU_CAP_EXTENDED_HW_TYPE) + return true; return false; } @@ -1683,6 +1690,7 @@ int x86_pmu_handle_irq(struct pt_regs *regs) struct cpu_hw_events *cpuc; struct perf_event *event; int idx, handled = 0; + u64 last_period; u64 val; cpuc = this_cpu_ptr(&cpu_hw_events); @@ -1702,6 +1710,7 @@ int x86_pmu_handle_irq(struct pt_regs *regs) continue; event = cpuc->events[idx]; + last_period = event->hw.last_period; val = static_call(x86_pmu_update)(event); if (val & (1ULL << (x86_pmu.cntval_bits - 1))) @@ -1715,12 +1724,11 @@ int x86_pmu_handle_irq(struct pt_regs *regs) if (!static_call(x86_pmu_set_period)(event)) continue; - perf_sample_data_init(&data, 0, event->hw.last_period); + perf_sample_data_init(&data, 0, last_period); perf_sample_save_brstack(&data, event, &cpuc->lbr_stack, NULL); - if (perf_event_overflow(event, &data, regs)) - x86_pmu_stop(event, 0); + perf_event_overflow(event, &data, regs); } if (handled) @@ -2046,6 +2054,11 @@ static void x86_pmu_static_call_update(void) static_call_update(x86_pmu_filter, x86_pmu.filter); static_call_update(x86_pmu_late_setup, x86_pmu.late_setup); + + static_call_update(x86_pmu_pebs_enable, x86_pmu.pebs_enable); + static_call_update(x86_pmu_pebs_disable, x86_pmu.pebs_disable); + static_call_update(x86_pmu_pebs_enable_all, x86_pmu.pebs_enable_all); + static_call_update(x86_pmu_pebs_disable_all, x86_pmu.pebs_disable_all); } static void _x86_pmu_read(struct perf_event *event) diff --git a/arch/x86/events/intel/bts.c b/arch/x86/events/intel/bts.c index a95e6c91c4d7..9560f693fac0 100644 --- a/arch/x86/events/intel/bts.c +++ b/arch/x86/events/intel/bts.c @@ -80,54 +80,54 @@ static void * bts_buffer_setup_aux(struct perf_event *event, void **pages, int nr_pages, bool overwrite) { - struct bts_buffer *buf; + struct bts_buffer *bb; struct page *page; int cpu = event->cpu; int node = (cpu == -1) ? cpu : cpu_to_node(cpu); unsigned long offset; size_t size = nr_pages << PAGE_SHIFT; - int pg, nbuf, pad; + int pg, nr_buf, pad; /* count all the high order buffers */ - for (pg = 0, nbuf = 0; pg < nr_pages;) { + for (pg = 0, nr_buf = 0; pg < nr_pages;) { page = virt_to_page(pages[pg]); pg += buf_nr_pages(page); - nbuf++; + nr_buf++; } /* * to avoid interrupts in overwrite mode, only allow one physical */ - if (overwrite && nbuf > 1) + if (overwrite && nr_buf > 1) return NULL; - buf = kzalloc_node(offsetof(struct bts_buffer, buf[nbuf]), GFP_KERNEL, node); - if (!buf) + bb = kzalloc_node(struct_size(bb, buf, nr_buf), GFP_KERNEL, node); + if (!bb) return NULL; - buf->nr_pages = nr_pages; - buf->nr_bufs = nbuf; - buf->snapshot = overwrite; - buf->data_pages = pages; - buf->real_size = size - size % BTS_RECORD_SIZE; + bb->nr_pages = nr_pages; + bb->nr_bufs = nr_buf; + bb->snapshot = overwrite; + bb->data_pages = pages; + bb->real_size = size - size % BTS_RECORD_SIZE; - for (pg = 0, nbuf = 0, offset = 0, pad = 0; nbuf < buf->nr_bufs; nbuf++) { + for (pg = 0, nr_buf = 0, offset = 0, pad = 0; nr_buf < bb->nr_bufs; nr_buf++) { unsigned int __nr_pages; page = virt_to_page(pages[pg]); __nr_pages = buf_nr_pages(page); - buf->buf[nbuf].page = page; - buf->buf[nbuf].offset = offset; - buf->buf[nbuf].displacement = (pad ? BTS_RECORD_SIZE - pad : 0); - buf->buf[nbuf].size = buf_size(page) - buf->buf[nbuf].displacement; - pad = buf->buf[nbuf].size % BTS_RECORD_SIZE; - buf->buf[nbuf].size -= pad; + bb->buf[nr_buf].page = page; + bb->buf[nr_buf].offset = offset; + bb->buf[nr_buf].displacement = (pad ? BTS_RECORD_SIZE - pad : 0); + bb->buf[nr_buf].size = buf_size(page) - bb->buf[nr_buf].displacement; + pad = bb->buf[nr_buf].size % BTS_RECORD_SIZE; + bb->buf[nr_buf].size -= pad; pg += __nr_pages; offset += __nr_pages << PAGE_SHIFT; } - return buf; + return bb; } static void bts_buffer_free_aux(void *data) @@ -135,25 +135,25 @@ static void bts_buffer_free_aux(void *data) kfree(data); } |
