From 459ec28ab404d7afcd512ce9b855959ad301605a Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sun, 13 Sep 2009 17:33:44 +0200 Subject: perf_counter: Allow mmap if paranoid checks are turned off Before: $ perf sched record -f sleep 1 Error: failed to mmap with 1 (Operation not permitted) After: $ perf sched record -f sleep 1 [ perf record: Captured and wrote 0.095 MB perf.data (~4161 samples) ] Note, this is only allowed if perfcounter_paranoid is set to the most permissive (non-default) value of -1. Cc: Peter Zijlstra Cc: Mike Galbraith Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Cc: Frederic Weisbecker LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index e0d91fdf0c3c..667ab25ad3d5 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -2315,7 +2315,8 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) lock_limit >>= PAGE_SHIFT; locked = vma->vm_mm->locked_vm + extra; - if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) { + if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && + !capable(CAP_IPC_LOCK)) { ret = -EPERM; goto unlock; } -- cgit v1.2.3 From f977bb4937857994312fff4f9c2cad336a36a932 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sun, 13 Sep 2009 18:15:54 +0200 Subject: perf_counter, sched: Add sched_stat_runtime tracepoint This allows more precise tracking of how the scheduler accounts (and acts upon) a task having spent N nanoseconds of CPU time. Cc: Peter Zijlstra Cc: Mike Galbraith Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Cc: Frederic Weisbecker LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/sched_fair.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel') diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index aa7f84121016..a097e909e80f 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -513,6 +513,7 @@ static void update_curr(struct cfs_rq *cfs_rq) if (entity_is_task(curr)) { struct task_struct *curtask = task_of(curr); + trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime); cpuacct_charge(curtask, delta_exec); account_group_exec_runtime(curtask, delta_exec); } -- cgit v1.2.3 From 850bc73ffcc99cddfb52bc23217c60810c508853 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 17 Sep 2009 18:47:11 +0200 Subject: perf_counter: Do not throttle single swcounter events We can have swcounter events that contribute more than a single count per event, when used with a non-zero period, those can generate multiple events, which is when we need throttling. However, swcounter that contribute only a single count per event can only come as fast as we can run code, hence don't throttle them. Signed-off-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 667ab25ad3d5..fe0d1adde804 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -3494,14 +3494,15 @@ static void perf_log_throttle(struct perf_counter *counter, int enable) * Generic counter overflow handling, sampling. */ -int perf_counter_overflow(struct perf_counter *counter, int nmi, - struct perf_sample_data *data) +static int __perf_counter_overflow(struct perf_counter *counter, int nmi, + int throttle, struct perf_sample_data *data) { int events = atomic_read(&counter->event_limit); - int throttle = counter->pmu->unthrottle != NULL; struct hw_perf_counter *hwc = &counter->hw; int ret = 0; + throttle = (throttle && counter->pmu->unthrottle != NULL); + if (!throttle) { hwc->interrupts++; } else { @@ -3554,6 +3555,12 @@ int perf_counter_overflow(struct perf_counter *counter, int nmi, return ret; } +int perf_counter_overflow(struct perf_counter *counter, int nmi, + struct perf_sample_data *data) +{ + return __perf_counter_overflow(counter, nmi, 1, data); +} + /* * Generic software counter infrastructure */ @@ -3592,6 +3599,7 @@ static void perf_swcounter_overflow(struct perf_counter *counter, int nmi, struct perf_sample_data *data) { struct hw_perf_counter *hwc = &counter->hw; + int throttle = 0; u64 overflow; data->period = counter->hw.last_period; @@ -3601,13 +3609,14 @@ static void perf_swcounter_overflow(struct perf_counter *counter, return; for (; overflow; overflow--) { - if (perf_counter_overflow(counter, nmi, data)) { + if (__perf_counter_overflow(counter, nmi, throttle, data)) { /* * We inhibit the overflow from happening when * hwc->interrupts == MAX_INTERRUPTS. */ break; } + throttle = 0; } } -- cgit v1.2.3 From 2667de81f3256c944b06abdf2c56c2f192fcb724 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 17 Sep 2009 19:01:10 +0200 Subject: perf_counter: Allow for a wakeup watermark Currently we wake the mmap() consumer once every PAGE_SIZE of data and/or once event wakeup_events when specified. For high speed sampling this results in too many wakeups wrt. the buffer size, hence change this. We move the default wakeup limit to 1/4-th the buffer size, and provide for means to manually specify this limit. Signed-off-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-) (limited to 'kernel') diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index fe0d1adde804..29b73b6e8146 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -2176,6 +2176,13 @@ static int perf_mmap_data_alloc(struct perf_counter *counter, int nr_pages) data->nr_pages = nr_pages; atomic_set(&data->lock, -1); + if (counter->attr.watermark) { + data->watermark = min_t(long, PAGE_SIZE * nr_pages, + counter->attr.wakeup_watermark); + } + if (!data->watermark) + data->watermark = max(PAGE_SIZE, PAGE_SIZE * nr_pages / 4); + rcu_assign_pointer(counter->data, data); return 0; @@ -2517,23 +2524,15 @@ struct perf_output_handle { unsigned long flags; }; -static bool perf_output_space(struct perf_mmap_data *data, - unsigned int offset, unsigned int head) +static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail, + unsigned long offset, unsigned long head) { - unsigned long tail; unsigned long mask; if (!data->writable) return true; mask = (data->nr_pages << PAGE_SHIFT) - 1; - /* - * Userspace could choose to issue a mb() before updating the tail - * pointer. So that all reads will be completed before the write is - * issued. - */ - tail = ACCESS_ONCE(data->user_page->data_tail); - smp_rmb(); offset = (offset - tail) & mask; head = (head - tail) & mask; @@ -2679,7 +2678,7 @@ static int perf_output_begin(struct perf_output_handle *handle, { struct perf_counter *output_counter; struct perf_mmap_data *data; - unsigned int offset, head; + unsigned long tail, offset, head; int have_lost; struct { struct perf_event_header header; @@ -2717,16 +2716,23 @@ static int perf_output_begin(struct perf_output_handle *handle, perf_output_lock(handle); do { + /* + * Userspace could choose to issue a mb() before updating the + * tail pointer. So that all reads will be completed before the + * write is issued. + */ + tail = ACCESS_ONCE(data->user_page->data_tail); + smp_rmb(); offset = head = atomic_long_read(&data->head); head += size; - if (unlikely(!perf_output_space(data, offset, head))) + if (unlikely(!perf_output_space(data, tail, offset, head))) goto fail; } while (atomic_long_cmpxchg(&data->head, offset, head) != offset); handle->offset = offset; handle->head = head; - if ((offset >> PAGE_SHIFT) != (head >> PAGE_SHIFT)) + if (head - tail > data->watermark) atomic_set(&data->wakeup, 1); if (have_lost) { -- cgit v1.2.3 From 5622f295b53fb60dbf9bed3e2c89d182490a8b7f Mon Sep 17 00:00:00 2001 From: Markus Metzger Date: Tue, 15 Sep 2009 13:00:23 +0200 Subject: x86, perf_counter, bts: Optimize BTS overflow handling Draining the BTS buffer on a buffer overflow interrupt takes too long resulting in a kernel lockup when tracing the kernel. Restructure perf_counter sampling into sample creation and sample output. Prepare a single reference sample for BTS sampling and update the from and to address fields when draining the BTS buffer. Drain the entire BTS buffer between a single perf_output_begin() / perf_output_end() pair. Signed-off-by: Markus Metzger Signed-off-by: Peter Zijlstra LKML-Reference: <20090915130023.A16204@sedona.ch.intel.com> Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 312 ++++++++++++++++++++++++++------------------------ 1 file changed, 165 insertions(+), 147 deletions(-) (limited to 'kernel') diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 29b73b6e8146..215845243a69 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -2512,18 +2512,6 @@ __weak struct perf_callchain_entry *perf_callchain(struct pt_regs *regs) /* * Output */ - -struct perf_output_handle { - struct perf_counter *counter; - struct perf_mmap_data *data; - unsigned long head; - unsigned long offset; - int nmi; - int sample; - int locked; - unsigned long flags; -}; - static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail, unsigned long offset, unsigned long head) { @@ -2633,8 +2621,8 @@ out: local_irq_restore(handle->flags); } -static void perf_output_copy(struct perf_output_handle *handle, - const void *buf, unsigned int len) +void perf_output_copy(struct perf_output_handle *handle, + const void *buf, unsigned int len) { unsigned int pages_mask; unsigned int offset; @@ -2669,12 +2657,9 @@ static void perf_output_copy(struct perf_output_handle *handle, WARN_ON_ONCE(((long)(handle->head - handle->offset)) < 0); } -#define perf_output_put(handle, x) \ - perf_output_copy((handle), &(x), sizeof(x)) - -static int perf_output_begin(struct perf_output_handle *handle, - struct perf_counter *counter, unsigned int size, - int nmi, int sample) +int perf_output_begin(struct perf_output_handle *handle, + struct perf_counter *counter, unsigned int size, + int nmi, int sample) { struct perf_counter *output_counter; struct perf_mmap_data *data; @@ -2756,7 +2741,7 @@ out: return -ENOSPC; } -static void perf_output_end(struct perf_output_handle *handle) +void perf_output_end(struct perf_output_handle *handle) { struct perf_counter *counter = handle->counter; struct perf_mmap_data *data = handle->data; @@ -2870,82 +2855,151 @@ static void perf_output_read(struct perf_output_handle *handle, perf_output_read_one(handle, counter); } -void perf_counter_output(struct perf_counter *counter, int nmi, - struct perf_sample_data *data) +void perf_output_sample(struct perf_output_handle *handle, + struct perf_event_header *header, + struct perf_sample_data *data, + struct perf_counter *counter) +{ + u64 sample_type = data->type; + + perf_output_put(handle, *header); + + if (sample_type & PERF_SAMPLE_IP) + perf_output_put(handle, data->ip); + + if (sample_type & PERF_SAMPLE_TID) + perf_output_put(handle, data->tid_entry); + + if (sample_type & PERF_SAMPLE_TIME) + perf_output_put(handle, data->time); + + if (sample_type & PERF_SAMPLE_ADDR) + perf_output_put(handle, data->addr); + + if (sample_type & PERF_SAMPLE_ID) + perf_output_put(handle, data->id); + + if (sample_type & PERF_SAMPLE_STREAM_ID) + perf_output_put(handle, data->stream_id); + + if (sample_type & PERF_SAMPLE_CPU) + perf_output_put(handle, data->cpu_entry); + + if (sample_type & PERF_SAMPLE_PERIOD) + perf_output_put(handle, data->period); + + if (sample_type & PERF_SAMPLE_READ) + perf_output_read(handle, counter); + + if (sample_type & PERF_SAMPLE_CALLCHAIN) { + if (data->callchain) { + int size = 1; + + if (data->callchain) + size += data->callchain->nr; + + size *= sizeof(u64); + + perf_output_copy(handle, data->callchain, size); + } else { + u64 nr = 0; + perf_output_put(handle, nr); + } + } + + if (sample_type & PERF_SAMPLE_RAW) { + if (data->raw) { + perf_output_put(handle, data->raw->size); + perf_output_copy(handle, data->raw->data, + data->raw->size); + } else { + struct { + u32 size; + u32 data; + } raw = { + .size = sizeof(u32), + .data = 0, + }; + perf_output_put(handle, raw); + } + } +} + +void perf_prepare_sample(struct perf_event_header *header, + struct perf_sample_data *data, + struct perf_counter *counter, + struct pt_regs *regs) { - int ret; u64 sample_type = counter->attr.sample_type; - struct perf_output_handle handle; - struct perf_event_header header; - u64 ip; - struct { - u32 pid, tid; - } tid_entry; - struct perf_callchain_entry *callchain = NULL; - int callchain_size = 0; - u64 time; - struct { - u32 cpu, reserved; - } cpu_entry; - header.type = PERF_EVENT_SAMPLE; - header.size = sizeof(header); + data->type = sample_type; - header.misc = 0; - header.misc |= perf_misc_flags(data->regs); + header->type = PERF_EVENT_SAMPLE; + header->size = sizeof(*header); + + header->misc = 0; + header->misc |= perf_misc_flags(regs); if (sample_type & PERF_SAMPLE_IP) { - ip = perf_instruction_pointer(data->regs); - header.size += sizeof(ip); + data->ip = perf_instruction_pointer(regs); + + header->size += sizeof(data->ip); } if (sample_type & PERF_SAMPLE_TID) { /* namespace issues */ - tid_entry.pid = perf_counter_pid(counter, current); - tid_entry.tid = perf_counter_tid(counter, current); + data->tid_entry.pid = perf_counter_pid(counter, current); + data->tid_entry.tid = perf_counter_tid(counter, current); - header.size += sizeof(tid_entry); + header->size += sizeof(data->tid_entry); } if (sample_type & PERF_SAMPLE_TIME) { /* * Maybe do better on x86 and provide cpu_clock_nmi() */ - time = sched_clock(); + data->time = sched_clock(); - header.size += sizeof(u64); + header->size += sizeof(data->time); } if (sample_type & PERF_SAMPLE_ADDR) - header.size += sizeof(u64); + header->size += sizeof(data->addr); - if (sample_type & PERF_SAMPLE_ID) - header.size += sizeof(u64); + if (sample_type & PERF_SAMPLE_ID) { + data->id = primary_counter_id(counter); - if (sample_type & PERF_SAMPLE_STREAM_ID) - header.size += sizeof(u64); + header->size += sizeof(data->id); + } + + if (sample_type & PERF_SAMPLE_STREAM_ID) { + data->stream_id = counter->id; + + header->size += sizeof(data->stream_id); + } if (sample_type & PERF_SAMPLE_CPU) { - header.size += sizeof(cpu_entry); + data->cpu_entry.cpu = raw_smp_processor_id(); + data->cpu_entry.reserved = 0; - cpu_entry.cpu = raw_smp_processor_id(); - cpu_entry.reserved = 0; + header->size += sizeof(data->cpu_entry); } if (sample_type & PERF_SAMPLE_PERIOD) - header.size += sizeof(u64); + header->size += sizeof(data->period); if (sample_type & PERF_SAMPLE_READ) - header.size += perf_counter_read_size(counter); + header->size += perf_counter_read_size(counter); if (sample_type & PERF_SAMPLE_CALLCHAIN) { - callchain = perf_callchain(data->regs); + int size = 1; - if (callchain) { - callchain_size = (1 + callchain->nr) * sizeof(u64); - header.size += callchain_size; - } else - header.size += sizeof(u64); + data->callchain = perf_callchain(regs); + + if (data->callchain) + size += data->callchain->nr; + + header->size += size * sizeof(u64); } if (sample_type & PERF_SAMPLE_RAW) { @@ -2957,69 +3011,23 @@ void perf_counter_output(struct perf_counter *counter, int nmi, size += sizeof(u32); WARN_ON_ONCE(size & (sizeof(u64)-1)); - header.size += size; - } - - ret = perf_output_begin(&handle, counter, header.size, nmi, 1); - if (ret) - return; - - perf_output_put(&handle, header); - - if (sample_type & PERF_SAMPLE_IP) - perf_output_put(&handle, ip); - - if (sample_type & PERF_SAMPLE_TID) - perf_output_put(&handle, tid_entry); - - if (sample_type & PERF_SAMPLE_TIME) - perf_output_put(&handle, time); - - if (sample_type & PERF_SAMPLE_ADDR) - perf_output_put(&handle, data->addr); - - if (sample_type & PERF_SAMPLE_ID) { - u64 id = primary_counter_id(counter); - - perf_output_put(&handle, id); + header->size += size; } +} - if (sample_type & PERF_SAMPLE_STREAM_ID) - perf_output_put(&handle, counter->id); - - if (sample_type & PERF_SAMPLE_CPU) - perf_output_put(&handle, cpu_entry); - - if (sample_type & PERF_SAMPLE_PERIOD) - perf_output_put(&handle, data->period); +static void perf_counter_output(struct perf_counter *counter, int nmi, + struct perf_sample_data *data, + struct pt_regs *regs) +{ + struct perf_output_handle handle; + struct perf_event_header header; - if (sample_type & PERF_SAMPLE_READ) - perf_output_read(&handle, counter); + perf_prepare_sample(&header, data, counter, regs); - if (sample_type & PERF_SAMPLE_CALLCHAIN) { - if (callchain) - perf_output_copy(&handle, callchain, callchain_size); - else { - u64 nr = 0; - perf_output_put(&handle, nr); - } - } + if (perf_output_begin(&handle, counter, header.size, nmi, 1)) + return; - if (sample_type & PERF_SAMPLE_RAW) { - if (data->raw) { - perf_output_put(&handle, data->raw->size); - perf_output_copy(&handle, data->raw->data, data->raw->size); - } else { - struct { - u32 size; - u32 data; - } raw = { - .size = sizeof(u32), - .data = 0, - }; - perf_output_put(&handle, raw); - } - } + perf_output_sample(&handle, &header, data, counter); perf_output_end(&handle); } @@ -3501,7 +3509,8 @@ static void perf_log_throttle(struct perf_counter *counter, int enable) */ static int __perf_counter_overflow(struct perf_counter *counter, int nmi, - int throttle, struct perf_sample_data *data) + int throttle, struct perf_sample_data *data, + struct pt_regs *regs) { int events = atomic_read(&counter->event_limit); struct hw_perf_counter *hwc = &counter->hw; @@ -3557,14 +3566,15 @@ static int __perf_counter_overflow(struct perf_counter *counter, int nmi, perf_counter_disable(counter); } - perf_counter_output(counter, nmi, data); + perf_counter_output(counter, nmi, data, regs); return ret; } int perf_counter_overflow(struct perf_counter *counter, int nmi, - struct perf_sample_data *data) + struct perf_sample_data *data, + struct pt_regs *regs) { - return __perf_counter_overflow(counter, nmi, 1, data); + return __perf_counter_overflow(counter, nmi, 1, data, regs); } /* @@ -3602,7 +3612,8 @@ again: } static void perf_swcounter_overflow(struct perf_counter *counter, - int nmi, struct perf_sample_data *data) + int nmi, struct perf_sample_data *data, + struct pt_regs *regs) { struct hw_perf_counter *hwc = &counter->hw; int throttle = 0; @@ -3615,7 +3626,8 @@ static void perf_swcounter_overflow(struct perf_counter *counter, return; for (; overflow; overflow--) { - if (__perf_counter_overflow(counter, nmi, throttle, data)) { + if (__perf_counter_overflow(counter, nmi, throttle, + data, regs)) { /* * We inhibit the overflow from happening when * hwc->interrupts == MAX_INTERRUPTS. @@ -3634,7 +3646,8 @@ static void perf_swcounter_unthrottle(struct perf_counter *counter) } static void perf_swcounter_add(struct perf_counter *counter, u64 nr, - int nmi, struct perf_sample_data *data) + int nmi, struct perf_sample_data *data, + struct pt_regs *regs) { struct hw_perf_counter *hwc = &counter->hw; @@ -3643,11 +3656,11 @@ static void perf_swcounter_add(struct perf_counter *counter, u64 nr, if (!hwc->sample_period) return; - if (!data->regs) + if (!regs) return; if (!atomic64_add_negative(nr, &hwc->period_left)) - perf_swcounter_overflow(counter, nmi, data); + perf_swcounter_overflow(counter, nmi, data, regs); } static int perf_swcounter_is_counting(struct perf_counter *counter) @@ -3706,7 +3719,8 @@ static int perf_swcounter_match(struct perf_counter *counter, static void perf_swcounter_ctx_event(struct perf_counter_context *ctx, enum perf_type_id type, u32 event, u64 nr, int nmi, - struct perf_sample_data *data) + struct perf_sample_data *data, + struct pt_regs *regs) { struct perf_counter *counter; @@ -3715,8 +3729,8 @@ static void perf_swcounter_ctx_event(struct perf_counter_context *ctx, rcu_read_lock(); list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) { - if (perf_swcounter_match(counter, type, event, data->regs)) - perf_swcounter_add(counter, nr, nmi, data); + if (perf_swcounter_match(counter, type, event, regs)) + perf_swcounter_add(counter, nr, nmi, data, regs); } rcu_read_unlock(); } @@ -3737,7 +3751,8 @@ static int *perf_swcounter_recursion_context(struct perf_cpu_context *cpuctx) static void do_perf_swcounter_event(enum perf_type_id type, u32 event, u64 nr, int nmi, - struct perf_sample_data *data) + struct perf_sample_data *data, + struct pt_regs *regs) { struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context); int *recursion = perf_swcounter_recursion_context(cpuctx); @@ -3750,7 +3765,7 @@ static void do_perf_swcounter_event(enum perf_type_id type, u32 event, barrier(); perf_swcounter_ctx_event(&cpuctx->ctx, type, event, - nr, nmi, data); + nr, nmi, data, regs); rcu_read_lock(); /* * doesn't really matter which of the child contexts the @@ -3758,7 +3773,7 @@ static void do_perf_swcounter_event(enum perf_type_id type, u32 event, */ ctx = rcu_dereference(current->perf_counter_ctxp); if (ctx) - perf_swcounter_ctx_event(ctx, type, event, nr, nmi, data); + perf_swcounter_ctx_event(ctx, type, event, nr, nmi, data, regs); rcu_read_unlock(); barrier(); @@ -3772,11 +3787,11 @@ void __perf_swcounter_event(u32 event, u64 nr, int nmi, struct pt_regs *regs, u64 addr) { struct perf_sample_data data = { - .regs = regs, .addr = addr, }; - do_perf_swcounter_event(PERF_TYPE_SOFTWARE, event, nr, nmi, &data); + do_perf_swcounter_event(PERF_TYPE_SOFTWARE, event, nr, nmi, + &data, regs); } static void perf_swcounter_read(struct perf_counter *counter) @@ -3813,6 +3828,7 @@ static enum hrtimer_restart perf_swcounter_hrtimer(struct hrtimer *hrtimer) { enum hrtimer_restart ret = HRTIMER_RESTART; struct perf_sample_data data; + struct pt_regs *regs; struct perf_counter *counter; u64 period; @@ -3820,17 +3836,17 @@ static enum hrtimer_restart perf_swcounter_hrtimer(struct hrtimer *hrtimer) counter->pmu->read(counter); data.addr = 0; - data.regs = get_irq_regs(); + regs = get_irq_regs(); /* * In case we exclude kernel IPs or are somehow not in interrupt * context, provide the next best thing, the user IP. */ - if ((counter->attr.exclude_kernel || !data.regs) && + if ((counter->attr.exclude_kernel || !regs) && !counter->attr.exclude_user) - data.regs = task_pt_regs(current); + regs = task_pt_regs(current); - if (data.regs) { - if (perf_counter_overflow(counter, 0, &data)) + if (regs) { + if (perf_counter_overflow(counter, 0, &data, regs)) ret = HRTIMER_NORESTART; } @@ -3966,15 +3982,17 @@ void perf_tpcounter_event(int event_id, u64 addr, u64 count, void *record, }; struct perf_sample_data data = { - .regs = get_irq_regs(), .addr = addr, .raw = &raw, }; - if (!data.regs) - data.regs = task_pt_regs(current); + struct pt_regs *regs = get_irq_regs(); + + if (!regs) + regs = task_pt_regs(current); - do_perf_swcounter_event(PERF_TYPE_TRACEPOINT, event_id, count, 1, &data); + do_perf_swcounter_event(PERF_TYPE_TRACEPOINT, event_id, count, 1, + &data, regs); } EXPORT_SYMBOL_GPL(perf_tpcounter_event); -- cgit v1.2.3 From cf450a7355a116af793998c118a6bcf7f5a8367e Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 18 Sep 2009 12:18:14 +0200 Subject: perf_counter: Fix up swcounter throttling /me dons the brown paper bag. Signed-off-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 215845243a69..6944bd55ec4e 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -3634,7 +3634,7 @@ static void perf_swcounter_overflow(struct perf_counter *counter, */ break; } - throttle = 0; + throttle = 1; } } -- cgit v1.2.3 From def0a9b2573e00ab0b486cb5382625203ab4c4a6 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 18 Sep 2009 20:14:01 +0200 Subject: sched_clock: Make it NMI safe Arjan complained about the suckyness of TSC on modern machines, and asked if we could do something about that for PERF_SAMPLE_TIME. Make cpu_clock() NMI safe by removing the spinlock and using cmpxchg. This also makes it smaller and more robust. Affects architectures that use HAVE_UNSTABLE_SCHED_CLOCK, i.e. IA64 and x86. Signed-off-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 9 ++-- kernel/sched_clock.c | 122 ++++++++++++++++++++++---------------------------- 2 files changed, 56 insertions(+), 75 deletions(-) (limited to 'kernel') diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 6944bd55ec4e..06d233a06da5 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -2955,10 +2955,7 @@ void perf_prepare_sample(struct perf_event_header *header, } if (sample_type & PERF_SAMPLE_TIME) { - /* - * Maybe do better on x86 and provide cpu_clock_nmi() - */ - data->time = sched_clock(); + data->time = perf_clock(); header->size += sizeof(data->time); } @@ -3488,7 +3485,7 @@ static void perf_log_throttle(struct perf_counter *counter, int enable) .misc = 0, .size = sizeof(throttle_event), }, - .time = sched_clock(), + .time = perf_clock(), .id = primary_counter_id(counter), .stream_id = counter->id, }; @@ -3540,7 +3537,7 @@ static int __perf_counter_overflow(struct perf_counter *counter, int nmi, } if (counter->attr.freq) { - u64 now = sched_clock(); + u64 now = perf_clock(); s64 delta = now - hwc->freq_stamp; hwc->freq_stamp = now; diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c index e1d16c9a7680..ac2e1dc708bd 100644 --- a/kernel/sched_clock.c +++ b/kernel/sched_clock.c @@ -48,13 +48,6 @@ static __read_mostly int sched_clock_running; __read_mostly int sched_clock_stable; struct sched_clock_data { - /* - * Raw spinlock - this is a special case: this might be called - * from within instrumentation code so we dont want to do any - * instrumentation ourselves. - */ - raw_spinlock_t lock; - u64 tick_raw; u64 tick_gtod; u64 clock; @@ -80,7 +73,6 @@ void sched_clock_init(void) for_each_possible_cpu(cpu) { struct sched_clock_data *scd = cpu_sdc(cpu); - scd->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; scd->tick_raw = 0; scd->tick_gtod = ktime_now; scd->clock = ktime_now; @@ -109,14 +101,19 @@ static inline u64 wrap_max(u64 x, u64 y) * - filter out backward motion * - use the GTOD tick value to create a window to filter crazy TSC values */ -static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now) +static u64 sched_clock_local(struct sched_clock_data *scd) { - s64 delta = now - scd->tick_raw; - u64 clock, min_clock, max_clock; + u64 now, clock, old_clock, min_clock, max_clock; + s64 delta; +again: + now = sched_clock(); + delta = now - scd->tick_raw; if (unlikely(delta < 0)) delta = 0; + old_clock = scd->clock; + /* * scd->clock = clamp(scd->tick_gtod + delta, * max(scd->tick_gtod, scd->clock), @@ -124,84 +121,73 @@ static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now) */ clock = scd->tick_gtod + delta; - min_clock = wrap_max(scd->tick_gtod, scd->clock); - max_clock = wrap_max(scd->clock, scd->tick_gtod + TICK_NSEC); + min_clock = wrap_max(scd->tick_gtod, old_clock); + max_clock = wrap_max(old_clock, scd->tick_gtod + TICK_NSEC); clock = wrap_max(clock, min_clock); clock = wrap_min(clock, max_clock); - scd->clock = clock; + if (cmpxchg(&scd->clock, old_clock, clock) != old_clock) + goto again; - return scd->clock; + return clock; } -static void lock_double_clock(struct sched_clock_data *data1, - struct sched_clock_data *data2) +static u64 sched_clock_remote(struct sched_clock_data *scd) { - if (data1 < data2) { - __raw_spin_lock(&data1->lock); - __raw_spin_lock(&data2->lock); + struct sched_clock_data *my_scd = this_scd(); + u64 this_clock, remote_clock; + u64 *ptr, old_val, val; + + sched_clock_local(my_scd); +again: + this_clock = my_scd->clock; + remote_clock = scd->clock; + + /* + * Use the opportunity that we have both locks + * taken to couple the two clocks: we take the + * larger time as the latest time for both + * runqueues. (this creates monotonic movement) + */ + if (likely((s64)(remote_clock - this_clock) < 0)) { + ptr = &scd->clock; + old_val = remote_clock; + val = this_clock; } else { - __raw_spin_lock(&data2->lock); - __raw_spin_lock(&data1->lock); + /* + * Should be rare, but possible: + */ + ptr = &my_scd->clock; + old_val = this_clock; + val = remote_clock; } + + if (cmpxchg(ptr, old_val, val) != old_val) + goto again; + + return val; } u64 sched_clock_cpu(int cpu) { - u64 now, clock, this_clock, remote_clock; struct sched_clock_data *scd; + u64 clock; + + WARN_ON_ONCE(!irqs_disabled()); if (sched_clock_stable) return sched_clock(); - scd = cpu_sdc(cpu); - - /* - * Normally this is not called in NMI context - but if it is, - * trying to do any locking here is totally lethal. - */ - if (unlikely(in_nmi())) - return scd->clock; - if (unlikely(!sched_clock_running)) return 0ull; - WARN_ON_ONCE(!irqs_disabled()); - now = sched_clock(); - - if (cpu != raw_smp_processor_id()) { - struct sched_clock_data *my_scd = this_scd(); - - lock_double_clock(scd, my_scd); - - this_clock = __update_sched_clock(my_scd, now); - remote_clock = scd->clock; - - /* - * Use the opportunity that we have both locks - * taken to couple the two clocks: we take the - * larger time as the latest time for both - * runqueues. (this creates monotonic movement) - */ - if (likely((s64)(remote_clock - this_clock) < 0)) { - clock = this_clock; - scd->clock = clock; - } else { - /* - * Should be rare, but possible: - */ - clock = remote_clock; - my_scd->clock = remote_clock; - } - - __raw_spin_unlock(&my_scd->lock); - } else { - __raw_spin_lock(&scd->lock); - clock = __update_sched_clock(scd, now); - } + scd = cpu_sdc(cpu); - __raw_spin_unlock(&scd->lock); + if (cpu != smp_processor_id()) + clock = sched_clock_remote(scd); + else + clock = sched_clock_local(scd); return clock; } @@ -223,11 +209,9 @@ void sched_clock_tick(void) now_gtod = ktime_to_ns(ktime_get()); now = sched_clock(); - __raw_spin_lock(&scd->lock); scd->tick_raw = now; scd->tick_gtod = now_gtod; - __update_sched_clock(scd, now); - __raw_spin_unlock(&scd->lock); + sched_clock_local(scd); } /* -- cgit v1.2.3 From 393b2ad8c757ba3ccd2a99ca5bbcd6db4d3fa53d Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Sat, 12 Sep 2009 07:52:47 +0200 Subject: perf: Add a timestamp to fork events perf timechart needs to know when a process forked, in order to be able to visualize properly when tasks start. This patch adds a time field to the event structure, and fills it in appropriately. Signed-off-by: Arjan van de Ven Acked-by: Peter Zijlstra Cc: Paul Mackerras Cc: Frederic Weisbecker LKML-Reference: <20090912130341.51ad2de2@infradead.org> Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index d013f4e89e9c..d5899b62b276 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -3083,6 +3083,7 @@ struct perf_task_event { u32 ppid; u32 tid; u32 ptid; + u64 time; } event; }; @@ -3090,9 +3091,12 @@ static void perf_counter_task_output(struct perf_counter *counter, struct perf_task_event *task_event) { struct perf_output_handle handle; - int size = task_event->event.header.size; + int size; struct task_struct *task = task_event->task; - int ret = perf_output_begin(&handle, counter, size, 0, 0); + int ret; + + size = task_event->event.header.size; + ret = perf_output_begin(&handle, counter, size, 0, 0); if (ret) return; @@ -3103,7 +3107,10 @@ static void perf_counter_task_output(struct perf_counter *counter, task_event->event.tid = perf_counter_tid(counter, task); task_event->event.ptid = perf_counter_tid(counter, current); + task_event->event.time = perf_clock(); + perf_output_put(&handle, task_event->event); + perf_output_end(&handle); } -- cgit v1.2.3 From 6161352142d5fed4cd753b32e5ccde66e705b14e Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Thu, 17 Sep 2009 16:11:28 +0200 Subject: tracing, perf: Convert the power tracer into an event tracer This patch converts the existing power tracer into an event tracer, so that power events (C states and frequency changes) can be tracked via "perf". This also removes the perl script that was used to demo the tracer; its functionality is being replaced entirely with timechart. Signed-off-by: Arjan van de Ven Acked-by: Peter Zijlstra Cc: Paul Mackerras Cc: Frederic Weisbecker LKML-Reference: <20090912130542.6d314860@infradead.org> Signed-off-by: Ingo Molnar --- kernel/trace/Makefile | 2 +- kernel/trace/power-traces.c | 20 ++++ kernel/trace/trace.h | 3 - kernel/trace/trace_entries.h | 17 ---- kernel/trace/trace_power.c | 218 ------------------------------------------- 5 files changed, 21 insertions(+), 239 deletions(-) create mode 100644 kernel/trace/power-traces.c delete mode 100644 kernel/trace/trace_power.c (limited to 'kernel') diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 844164dca90a..26f03ac07c2b 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -42,7 +42,6 @@ obj-$(CONFIG_BOOT_TRACER) += trace_boot.o obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o obj-$(CONFIG_HW_BRANCH_TRACER) += trace_hw_branches.o -obj-$(CONFIG_POWER_TRACER) += trace_power.o obj-$(CONFIG_KMEMTRACE) += kmemtrace.o obj-$(CONFIG_WORKQUEUE_TRACER) += trace_workqueue.o obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o @@ -54,5 +53,6 @@ obj-$(CONFIG_EVENT_TRACING) += trace_export.o obj-$(CONFIG_FTRACE_SYSCALLS) += trace_syscalls.o obj-$(CONFIG_EVENT_PROFILE) += trace_event_profile.o obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o +obj-$(CONFIG_EVENT_TRACING) += power-traces.o libftrace-y := ftrace.o diff --git a/kernel/trace/power-traces.c b/kernel/trace/power-traces.c new file mode 100644 index 000000000000..e06c6e3d56a3 --- /dev/null +++ b/kernel/trace/power-traces.c @@ -0,0 +1,20 @@ +/* + * Power trace points + * + * Copyright (C) 2009 Arjan van de Ven + */ + +#include +#include +#include +#include +#include +#include + +#define CREATE_TRACE_POINTS +#include + +EXPORT_TRACEPOINT_SYMBOL_GPL(power_start); +EXPORT_TRACEPOINT_SYMBOL_GPL(power_end); +EXPORT_TRACEPOINT_SYMBOL_GPL(power_frequency); + diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 86bcff94791a..405cb850b75d 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -11,7 +11,6 @@ #include #include #include -#include #include #include @@ -37,7 +36,6 @@ enum trace_type { TRACE_HW_BRANCHES, TRACE_KMEM_ALLOC, TRACE_KMEM_FREE, - TRACE_POWER, TRACE_BLK, __TRACE_LAST_TYPE, @@ -207,7 +205,6 @@ extern void __ftrace_bad_type(void); IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ TRACE_GRAPH_RET); \ IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\ - IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \ IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \ TRACE_KMEM_ALLOC); \ IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \ diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h index a431748ddd6e..ead3d724599d 100644 --- a/kernel/trace/trace_entries.h +++ b/kernel/trace/trace_entries.h @@ -330,23 +330,6 @@ FTRACE_ENTRY(hw_branch, hw_branch_entry, F_printk("from: %llx to: %llx", __entry->from, __entry->to) ); -FTRACE_ENTRY(power, trace_power, - - TRACE_POWER, - - F_STRUCT( - __field_struct( struct power_trace, state_data ) - __field_desc( s64, state_data, stamp ) - __field_desc( s64, state_data, end ) - __field_desc( int, state_data, type ) - __field_desc( int, state_data, state ) - ), - - F_printk("%llx->%llx type:%u state:%u", - __entry->stamp, __entry->end, - __entry->type, __entry->state) -); - FTRACE_ENTRY(kmem_alloc, kmemtrace_alloc_entry, TRACE_KMEM_ALLOC, diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c deleted file mode 100644 index fe1a00f1445a..000000000000 --- a/kernel/trace/trace_power.c +++ /dev/null @@ -1,218 +0,0 @@ -/* - * ring buffer based C-state tracer - * - * Arjan van de Ven - * Copyright (C) 2008 Intel Corporation - * - * Much is borrowed from trace_boot.c which is - * Copyright (C) 2008 Frederic Weisbecker - * - */ - -#include -#include -#include -#include -#include - -#include "trace.h" -#include "trace_output.h" - -static struct trace_array *power_trace; -static int __read_mostly trace_power_enabled; - -static void probe_power_start(struct power_trace *it, unsigned int type, - unsigned int level) -{ - if (!trace_power_enabled) - return; - - memset(it, 0, sizeof(struct power_trace)); - it->state = level; - it->type = type; - it->stamp = ktime_get(); -} - - -static void probe_power_end(struct power_trace *it) -{ - struct ftrace_event_call *call = &event_power; - struct ring_buffer_event *event; - struct ring_buffer *buffer; - struct trace_power *entry; - struct trace_array_cpu *data; - struct trace_array *tr = power_trace; - - if (!trace_power_enabled) - return; - - buffer = tr->buffer; - - preempt_disable(); - it->end = ktime_get(); - data = tr->data[smp_processor_id()]; - - event = trace_buffer_lock_reserve(buffer, TRACE_POWER, - sizeof(*entry), 0, 0); - if (!event) - goto out; - entry = ring_buffer_event_data(event); - entry->state_data = *it; - if (!filter_check_discard(call, entry, buffer, event)) - trace_buffer_unlock_commit(buffer, event, 0, 0); - out: - preempt_enable(); -} - -static void probe_power_mark(struct power_trace *it, unsigned int type, - unsigned int level) -{ - struct ftrace_event_call *call = &event_power; - struct ring_buffer_event *event; - struct ring_buffer *buffer; - struct trace_power *entry; - struct trace_array_cpu *data; - struct trace_array *tr = power_trace; - - if (!trace_power_enabled) - return; - - buffer = tr->buffer; - - memset(it, 0, sizeof(struct power_trace)); - it->state = level; - it->type = type; - it->stamp = ktime_get(); - preempt_disable(); - it->end = it->stamp; - data = tr->data[smp_processor_id()]; - - event = trace_buffer_lock_reserve(buffer, TRACE_POWER, - sizeof(*entry), 0, 0); - if (!event) - goto out; - entry = ring_buffer_event_data(event); - entry->state_data = *it; - if (!filter_check_discard(call, entry, buffer, event)) - trace_buffer_unlock_commit(buffer, event, 0, 0); - out: - preempt_enable(); -} - -static int tracing_power_register(void) -{ - int ret; - - ret = register_trace_power_start(probe_power_start); - if (ret) { - pr_info("power trace: Couldn't activate tracepoint" - " probe to trace_power_start\n"); - return ret; - } - ret = register_trace_power_end(probe_power_end); - if (ret) { - pr_info("power trace: Couldn't activate tracepoint" - " probe to trace_power_end\n"); - goto fail_start; - } - ret = register_trace_power_mark(probe_power_mark); - if (ret) { - pr_info("power trace: Couldn't activate tracepoint" - " probe to trace_power_mark\n"); - goto fail_end; - } - return ret; -fail_end: - unregister_trace_power_end(probe_power_end); -fail_start: - unregister_trace_power_start(probe_power_start); - return ret; -} - -static void start_power_trace(struct trace_array *tr) -{ - trace_power_enabled = 1; -} - -static void stop_power_trace(struct trace_array *tr) -{ - trace_power_enabled = 0; -} - -static void power_trace_reset(struct trace_array *tr) -{ - trace_power_enabled = 0; - unregister_trace_power_start(probe_power_start); - unregister_trace_power_end(probe_power_end); - unregister_trace_power_mark(probe_power_mark); -} - - -static int power_trace_init(struct trace_array *tr) -{ - power_trace = tr; - - trace_power_enabled = 1; - tracing_power_register(); - - tracing_reset_online_cpus(tr); - return 0; -} - -static enum print_line_t power_print_line(struct trace_iterator *iter) -{ - int ret = 0; - struct trace_entry *entry = iter->ent; - struct trace_power *field ; - struct power_trace *it; - struct trace_seq *s = &iter->seq; - struct timespec stamp; - struct timespec duration; - - trace_assign_type(field, entry); - it = &field->state_data; - stamp = ktime_to_timespec(it->stamp); - duration = ktime_to_timespec(ktime_sub(it->end, it->stamp)); - - if (entry->type == TRACE_POWER) { - if (it->type == POWER_CSTATE) - ret = trace_seq_printf(s, "[%5ld.%09ld] CSTATE: Going to C%i on cpu %i for %ld.%09ld\n", - stamp.tv_sec, - stamp.tv_nsec, - it->state, iter->cpu, - duration.tv_sec, - duration.tv_nsec); - if (it->type == POWER_PSTATE) - ret = trace_seq_printf(s, "[%5ld.%09ld] PSTATE: Going to P%i on cpu %i\n", - stamp.tv_sec, - stamp.tv_nsec, - it->state, iter->cpu); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - return TRACE_TYPE_HANDLED; - } - return TRACE_TYPE_UNHANDLED; -} - -static void power_print_header(struct seq_file *s) -{ - seq_puts(s, "# TIMESTAMP STATE EVENT\n"); - seq_puts(s, "# | | |\n"); -} - -static struct tracer power_tracer __read_mostly = -{ - .name = "power", - .init = power_trace_init, - .start = start_power_trace, - .stop = stop_power_trace, - .reset = power_trace_reset, - .print_line = power_print_line, - .print_header = power_print_header, -}; - -static int init_power_trace(void) -{ - return register_tracer(&power_tracer); -} -device_initcall(init_power_trace); -- cgit v1.2.3 From cdf8073d6b2c6c5a3cd6ce0e6c1297157f7f99ba Mon Sep 17 00:00:00 2001 From: Ian Schram Date: Fri, 18 Sep 2009 21:26:26 +0200 Subject: perf_counter: Fix perf_copy_attr() pointer arithmetic There is still some weird code in per_copy_attr(). Which supposedly checks that all bytes trailing a struct are zero. It doesn't seem to get pointer arithmetic right. Since it increments an iterating pointer by sizeof(unsigned long) rather than 1. Signed-off-by: Ian Schram [ v2: clean up the messy PTR_ALIGN logic as well. ] Signed-off-by: Peter Zijlstra Cc: Mike Galbraith Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Cc: Frederic Weisbecker Cc: # for v2.6.31.x LKML-Reference: <4AB3DEE2.3030600@telenet.be> Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) (limited to 'kernel') diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index d5899b62b276..cc768ab81ac8 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -4208,8 +4208,8 @@ done: static int perf_copy_attr(struct perf_counter_attr __user *uattr, struct perf_counter_attr *attr) { - int ret; u32 size; + int ret; if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) return -EFAULT; @@ -4234,19 +4234,19 @@ static int perf_copy_attr(struct perf_counter_attr __user *uattr, /* * If we're handed a bigger struct than we know of, - * ensure all the unknown bits are 0. + * ensure all the unknown bits are 0 - i.e. new + * user-space does not rely on any kernel feature + * extensions we dont know about yet. */ if (size > sizeof(*attr)) { - unsigned long val; - unsigned long __user *addr; - unsigned long __user *end; + unsigned char __user *addr; + unsigned char __user *end; + unsigned char val; - addr = PTR_ALIGN((void __user *)uattr + sizeof(*attr), - sizeof(unsigned long)); - end = PTR_ALIGN((void __user *)uattr + size, - sizeof(unsigned long)); + addr = (void __user *)uattr + sizeof(*attr); + end = (void __user *)uattr + size; - for (; addr < end; addr += sizeof(unsigned long)) { + for (; addr < end; addr++) { ret = get_user(val, addr); if (ret) return ret; -- cgit v1.2.3