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Diffstat (limited to 'kernel/trace/ring_buffer.c')
-rw-r--r--kernel/trace/ring_buffer.c122
1 files changed, 95 insertions, 27 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 731201bf4ac..f5b7b5c1195 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -478,7 +478,7 @@ struct ring_buffer_per_cpu {
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;
@@ -488,12 +488,14 @@ struct ring_buffer_per_cpu {
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;
};
@@ -1062,7 +1064,7 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu)
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;
@@ -1259,7 +1261,7 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned nr_pages)
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++) {
@@ -1277,7 +1279,7 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned nr_pages)
rb_check_pages(cpu_buffer);
out:
- spin_unlock_irq(&cpu_buffer->reader_lock);
+ raw_spin_unlock_irq(&cpu_buffer->reader_lock);
}
static void
@@ -1288,7 +1290,7 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer,
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++) {
@@ -1303,7 +1305,7 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer,
rb_check_pages(cpu_buffer);
out:
- spin_unlock_irq(&cpu_buffer->reader_lock);
+ raw_spin_unlock_irq(&cpu_buffer->reader_lock);
}
/**
@@ -1708,6 +1710,7 @@ rb_handle_head_page(struct ring_buffer_per_cpu *cpu_buffer,
* 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
@@ -1863,6 +1866,9 @@ rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer,
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
@@ -2054,6 +2060,9 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
if (!tail)
tail_page->page->time_stamp = ts;
+ /* account for these added bytes */
+ local_add(length, &cpu_buffer->entries_bytes);
+
return event;
}
@@ -2076,6 +2085,7 @@ rb_try_to_discard(struct ring_buffer_per_cpu *cpu_buffer,
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
@@ -2085,8 +2095,11 @@ rb_try_to_discard(struct ring_buffer_per_cpu *cpu_buffer,
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 */
@@ -2661,6 +2674,58 @@ rb_num_of_entries(struct ring_buffer_per_cpu *cpu_buffer)
}
/**
+ * 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;
+
+ 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);
+ 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: The per CPU buffer to get the entries from.
@@ -2804,9 +2869,9 @@ void ring_buffer_iter_reset(struct ring_buffer_iter *iter)
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);
@@ -3265,12 +3330,12 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts,
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)
@@ -3295,9 +3360,9 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts)
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;
@@ -3337,7 +3402,7 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts,
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) {
@@ -3346,7 +3411,7 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts,
}
if (dolock)
- spin_unlock(&cpu_buffer->reader_lock);
+ raw_spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
out:
@@ -3438,11 +3503,11 @@ ring_buffer_read_start(struct ring_buffer_iter *iter)
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);
@@ -3477,7 +3542,7 @@ ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts)
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)
@@ -3488,7 +3553,7 @@ ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts)
rb_advance_iter(iter);
out:
- spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
return event;
}
@@ -3527,11 +3592,13 @@ rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer)
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;
@@ -3557,7 +3624,7 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu)
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;
@@ -3569,7 +3636,7 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu)
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);
}
@@ -3607,10 +3674,10 @@ int ring_buffer_empty(struct ring_buffer *buffer)
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)
@@ -3641,10 +3708,10 @@ int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu)
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;
@@ -3841,7 +3908,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
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)
@@ -3918,6 +3985,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
} 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);
@@ -3964,7 +4032,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
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;
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 02:02:55 +0000