int cpu;
atomic_t record_disabled;
struct ring_buffer *buffer;
- spinlock_t reader_lock; /* serialize readers */
+ raw_spinlock_t reader_lock; /* serialize readers */
arch_spinlock_t lock;
struct lock_class_key lock_key;
struct list_head *pages;
struct buffer_page *reader_page;
unsigned long lost_events;
unsigned long last_overrun;
+ local_t entries_bytes;
local_t commit_overrun;
local_t overrun;
local_t entries;
local_t committing;
local_t commits;
unsigned long read;
+ unsigned long read_bytes;
u64 write_stamp;
u64 read_stamp;
};
cpu_buffer->cpu = cpu;
cpu_buffer->buffer = buffer;
- spin_lock_init(&cpu_buffer->reader_lock);
+ raw_spin_lock_init(&cpu_buffer->reader_lock);
lockdep_set_class(&cpu_buffer->reader_lock, buffer->reader_lock_key);
cpu_buffer->lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
struct list_head *p;
unsigned i;
- spin_lock_irq(&cpu_buffer->reader_lock);
+ raw_spin_lock_irq(&cpu_buffer->reader_lock);
rb_head_page_deactivate(cpu_buffer);
for (i = 0; i < nr_pages; i++) {
rb_check_pages(cpu_buffer);
out:
- spin_unlock_irq(&cpu_buffer->reader_lock);
+ raw_spin_unlock_irq(&cpu_buffer->reader_lock);
}
static void
struct list_head *p;
unsigned i;
- spin_lock_irq(&cpu_buffer->reader_lock);
+ raw_spin_lock_irq(&cpu_buffer->reader_lock);
rb_head_page_deactivate(cpu_buffer);
for (i = 0; i < nr_pages; i++) {
rb_check_pages(cpu_buffer);
out:
- spin_unlock_irq(&cpu_buffer->reader_lock);
+ raw_spin_unlock_irq(&cpu_buffer->reader_lock);
}
/**
* the counters.
*/
local_add(entries, &cpu_buffer->overrun);
+ local_sub(BUF_PAGE_SIZE, &cpu_buffer->entries_bytes);
/*
* The entries will be zeroed out when we move the
event = __rb_page_index(tail_page, tail);
kmemcheck_annotate_bitfield(event, bitfield);
+ /* account for padding bytes */
+ local_add(BUF_PAGE_SIZE - tail, &cpu_buffer->entries_bytes);
+
/*
* Save the original length to the meta data.
* This will be used by the reader to add lost event
write &= RB_WRITE_MASK;
tail = write - length;
+ /*
+ * If this is the first commit on the page, then it has the same
+ * timestamp as the page itself.
+ */
+ if (!tail)
+ delta = 0;
+
/* See if we shot pass the end of this buffer page */
if (unlikely(write > BUF_PAGE_SIZE))
return rb_move_tail(cpu_buffer, length, tail,
if (!tail)
tail_page->page->time_stamp = ts;
+ /* account for these added bytes */
+ local_add(length, &cpu_buffer->entries_bytes);
+
return event;
}
if (bpage->page == (void *)addr && rb_page_write(bpage) == old_index) {
unsigned long write_mask =
local_read(&bpage->write) & ~RB_WRITE_MASK;
+ unsigned long event_length = rb_event_length(event);
/*
* This is on the tail page. It is possible that
* a write could come in and move the tail page
old_index += write_mask;
new_index += write_mask;
index = local_cmpxchg(&bpage->write, old_index, new_index);
- if (index == old_index)
+ if (index == old_index) {
+ /* update counters */
+ local_sub(event_length, &cpu_buffer->entries_bytes);
return 1;
+ }
}
/* could not discard */
(local_read(&cpu_buffer->overrun) + cpu_buffer->read);
}
+/**
+ * ring_buffer_oldest_event_ts - get the oldest event timestamp from the buffer
+ * @buffer: The ring buffer
+ * @cpu: The per CPU buffer to read from.
+ */
+unsigned long ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu)
+{
+ unsigned long flags;
+ struct ring_buffer_per_cpu *cpu_buffer;
+ struct buffer_page *bpage;
+ unsigned long ret = 0;
+
+ if (!cpumask_test_cpu(cpu, buffer->cpumask))
+ return 0;
+
+ cpu_buffer = buffer->buffers[cpu];
+ raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ /*
+ * if the tail is on reader_page, oldest time stamp is on the reader
+ * page
+ */
+ if (cpu_buffer->tail_page == cpu_buffer->reader_page)
+ bpage = cpu_buffer->reader_page;
+ else
+ bpage = rb_set_head_page(cpu_buffer);
+ if (bpage)
+ ret = bpage->page->time_stamp;
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ring_buffer_oldest_event_ts);
+
+/**
+ * ring_buffer_bytes_cpu - get the number of bytes consumed in a cpu buffer
+ * @buffer: The ring buffer
+ * @cpu: The per CPU buffer to read from.
+ */
+unsigned long ring_buffer_bytes_cpu(struct ring_buffer *buffer, int cpu)
+{
+ struct ring_buffer_per_cpu *cpu_buffer;
+ unsigned long ret;
+
+ if (!cpumask_test_cpu(cpu, buffer->cpumask))
+ return 0;
+
+ cpu_buffer = buffer->buffers[cpu];
+ ret = local_read(&cpu_buffer->entries_bytes) - cpu_buffer->read_bytes;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ring_buffer_bytes_cpu);
+
/**
* ring_buffer_entries_cpu - get the number of entries in a cpu buffer
* @buffer: The ring buffer
cpu_buffer = iter->cpu_buffer;
- spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
rb_iter_reset(iter);
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
}
EXPORT_SYMBOL_GPL(ring_buffer_iter_reset);
* Splice the empty reader page into the list around the head.
*/
reader = rb_set_head_page(cpu_buffer);
+ if (!reader)
+ goto out;
cpu_buffer->reader_page->list.next = rb_list_head(reader->list.next);
cpu_buffer->reader_page->list.prev = reader->list.prev;
return NULL;
/*
- * We repeat when a time extend is encountered.
- * Since the time extend is always attached to a data event,
- * we should never loop more than once.
- * (We never hit the following condition more than twice).
+ * We repeat when a time extend is encountered or we hit
+ * the end of the page. Since the time extend is always attached
+ * to a data event, we should never loop more than three times.
+ * Once for going to next page, once on time extend, and
+ * finally once to get the event.
+ * (We never hit the following condition more than thrice).
*/
- if (RB_WARN_ON(cpu_buffer, ++nr_loops > 2))
+ if (RB_WARN_ON(cpu_buffer, ++nr_loops > 3))
return NULL;
if (rb_per_cpu_empty(cpu_buffer))
again:
local_irq_save(flags);
if (dolock)
- spin_lock(&cpu_buffer->reader_lock);
+ raw_spin_lock(&cpu_buffer->reader_lock);
event = rb_buffer_peek(cpu_buffer, ts, lost_events);
if (event && event->type_len == RINGBUF_TYPE_PADDING)
rb_advance_reader(cpu_buffer);
if (dolock)
- spin_unlock(&cpu_buffer->reader_lock);
+ raw_spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
if (event && event->type_len == RINGBUF_TYPE_PADDING)
unsigned long flags;
again:
- spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
event = rb_iter_peek(iter, ts);
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
if (event && event->type_len == RINGBUF_TYPE_PADDING)
goto again;
cpu_buffer = buffer->buffers[cpu];
local_irq_save(flags);
if (dolock)
- spin_lock(&cpu_buffer->reader_lock);
+ raw_spin_lock(&cpu_buffer->reader_lock);
event = rb_buffer_peek(cpu_buffer, ts, lost_events);
if (event) {
}
if (dolock)
- spin_unlock(&cpu_buffer->reader_lock);
+ raw_spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
out:
cpu_buffer = iter->cpu_buffer;
- spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
arch_spin_lock(&cpu_buffer->lock);
rb_iter_reset(iter);
arch_spin_unlock(&cpu_buffer->lock);
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
}
EXPORT_SYMBOL_GPL(ring_buffer_read_start);
struct ring_buffer_per_cpu *cpu_buffer = iter->cpu_buffer;
unsigned long flags;
- spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
again:
event = rb_iter_peek(iter, ts);
if (!event)
rb_advance_iter(iter);
out:
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
return event;
}
cpu_buffer->reader_page->read = 0;
local_set(&cpu_buffer->commit_overrun, 0);
+ local_set(&cpu_buffer->entries_bytes, 0);
local_set(&cpu_buffer->overrun, 0);
local_set(&cpu_buffer->entries, 0);
local_set(&cpu_buffer->committing, 0);
local_set(&cpu_buffer->commits, 0);
cpu_buffer->read = 0;
+ cpu_buffer->read_bytes = 0;
cpu_buffer->write_stamp = 0;
cpu_buffer->read_stamp = 0;
atomic_inc(&cpu_buffer->record_disabled);
- spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
if (RB_WARN_ON(cpu_buffer, local_read(&cpu_buffer->committing)))
goto out;
arch_spin_unlock(&cpu_buffer->lock);
out:
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
atomic_dec(&cpu_buffer->record_disabled);
}
cpu_buffer = buffer->buffers[cpu];
local_irq_save(flags);
if (dolock)
- spin_lock(&cpu_buffer->reader_lock);
+ raw_spin_lock(&cpu_buffer->reader_lock);
ret = rb_per_cpu_empty(cpu_buffer);
if (dolock)
- spin_unlock(&cpu_buffer->reader_lock);
+ raw_spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
if (!ret)
cpu_buffer = buffer->buffers[cpu];
local_irq_save(flags);
if (dolock)
- spin_lock(&cpu_buffer->reader_lock);
+ raw_spin_lock(&cpu_buffer->reader_lock);
ret = rb_per_cpu_empty(cpu_buffer);
if (dolock)
- spin_unlock(&cpu_buffer->reader_lock);
+ raw_spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
return ret;
if (!bpage)
goto out;
- spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
reader = rb_get_reader_page(cpu_buffer);
if (!reader)
} else {
/* update the entry counter */
cpu_buffer->read += rb_page_entries(reader);
+ cpu_buffer->read_bytes += BUF_PAGE_SIZE;
/* swap the pages */
rb_init_page(bpage);
memset(&bpage->data[commit], 0, BUF_PAGE_SIZE - commit);
out_unlock:
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
out:
return ret;
git.openpandora.org / pandora-kernel.git / blobdiff