int tracing_alloc_snapshot_instance(struct trace_array *tr)
{
+ int order;
int ret;
if (!tr->allocated_snapshot) {
+ /* Make the snapshot buffer have the same order as main buffer */
+ order = ring_buffer_subbuf_order_get(tr->array_buffer.buffer);
+ ret = ring_buffer_subbuf_order_set(tr->max_buffer.buffer, order);
+ if (ret < 0)
+ return ret;
+
/* allocate spare buffer */
ret = resize_buffer_duplicate_size(&tr->max_buffer,
&tr->array_buffer, RING_BUFFER_ALL_CPUS);
* The max_tr ring buffer has some state (e.g. ring->clock) and
* we want preserve it.
*/
+ ring_buffer_subbuf_order_set(tr->max_buffer.buffer, 0);
ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS);
set_buffer_entries(&tr->max_buffer, 1);
tracing_reset_online_cpus(&tr->max_buffer);
/* OK if part of the temp seq buffer */
if ((addr >= (unsigned long)iter->tmp_seq.buffer) &&
- (addr < (unsigned long)iter->tmp_seq.buffer + PAGE_SIZE))
+ (addr < (unsigned long)iter->tmp_seq.buffer + TRACE_SEQ_BUFFER_SIZE))
return true;
/* Core rodata can not be freed */
return 0;
}
-static int tracing_release_generic_tr(struct inode *inode, struct file *file)
+int tracing_release_generic_tr(struct inode *inode, struct file *file)
{
struct trace_array *tr = inode->i_private;
goto out;
}
- if (cnt >= PAGE_SIZE)
- cnt = PAGE_SIZE - 1;
+ if (cnt >= TRACE_SEQ_BUFFER_SIZE)
+ cnt = TRACE_SEQ_BUFFER_SIZE - 1;
/* reset all but tr, trace, and overruns */
trace_iterator_reset(iter);
enum event_trigger_type tt = ETT_NONE;
struct trace_buffer *buffer;
struct print_entry *entry;
+ int meta_size;
ssize_t written;
- int size;
+ size_t size;
int len;
/* Used in tracing_mark_raw_write() as well */
if (!(tr->trace_flags & TRACE_ITER_MARKERS))
return -EINVAL;
- if (cnt > TRACE_BUF_SIZE)
- cnt = TRACE_BUF_SIZE;
-
- BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);
+ if ((ssize_t)cnt < 0)
+ return -EINVAL;
- size = sizeof(*entry) + cnt + 2; /* add '\0' and possible '\n' */
+ meta_size = sizeof(*entry) + 2; /* add '\0' and possible '\n' */
+ again:
+ size = cnt + meta_size;
/* If less than "<faulted>", then make sure we can still add that */
if (cnt < FAULTED_SIZE)
size += FAULTED_SIZE - cnt;
+ if (size > TRACE_SEQ_BUFFER_SIZE) {
+ cnt -= size - TRACE_SEQ_BUFFER_SIZE;
+ goto again;
+ }
+
buffer = tr->array_buffer.buffer;
event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
tracing_gen_ctx());
- if (unlikely(!event))
+ if (unlikely(!event)) {
+ /*
+ * If the size was greater than what was allowed, then
+ * make it smaller and try again.
+ */
+ if (size > ring_buffer_max_event_size(buffer)) {
+ /* cnt < FAULTED size should never be bigger than max */
+ if (WARN_ON_ONCE(cnt < FAULTED_SIZE))
+ return -EBADF;
+ cnt = ring_buffer_max_event_size(buffer) - meta_size;
+ /* The above should only happen once */
+ if (WARN_ON_ONCE(cnt + meta_size == size))
+ return -EBADF;
+ goto again;
+ }
+
/* Ring buffer disabled, return as if not open for write */
return -EBADF;
+ }
entry = ring_buffer_event_data(event);
entry->ip = _THIS_IP_;
return written;
}
-/* Limit it for now to 3K (including tag) */
-#define RAW_DATA_MAX_SIZE (1024*3)
-
static ssize_t
tracing_mark_raw_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *fpos)
return -EINVAL;
/* The marker must at least have a tag id */
- if (cnt < sizeof(unsigned int) || cnt > RAW_DATA_MAX_SIZE)
+ if (cnt < sizeof(unsigned int))
return -EINVAL;
- if (cnt > TRACE_BUF_SIZE)
- cnt = TRACE_BUF_SIZE;
-
- BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);
-
size = sizeof(*entry) + cnt;
if (cnt < FAULT_SIZE_ID)
size += FAULT_SIZE_ID - cnt;
buffer = tr->array_buffer.buffer;
+
+ if (size > ring_buffer_max_event_size(buffer))
+ return -EINVAL;
+
event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size,
tracing_gen_ctx());
if (!event)
struct trace_iterator iter;
void *spare;
unsigned int spare_cpu;
+ unsigned int spare_size;
unsigned int read;
};
{
struct ftrace_buffer_info *info = filp->private_data;
struct trace_iterator *iter = &info->iter;
+ void *trace_data;
+ int page_size;
ssize_t ret = 0;
ssize_t size;
return -EBUSY;
#endif
+ page_size = ring_buffer_subbuf_size_get(iter->array_buffer->buffer);
+
+ /* Make sure the spare matches the current sub buffer size */
+ if (info->spare) {
+ if (page_size != info->spare_size) {
+ ring_buffer_free_read_page(iter->array_buffer->buffer,
+ info->spare_cpu, info->spare);
+ info->spare = NULL;
+ }
+ }
+
if (!info->spare) {
info->spare = ring_buffer_alloc_read_page(iter->array_buffer->buffer,
iter->cpu_file);
info->spare = NULL;
} else {
info->spare_cpu = iter->cpu_file;
+ info->spare_size = page_size;
}
}
if (!info->spare)
return ret;
/* Do we have previous read data to read? */
- if (info->read < PAGE_SIZE)
+ if (info->read < page_size)
goto read;
again:
trace_access_lock(iter->cpu_file);
ret = ring_buffer_read_page(iter->array_buffer->buffer,
- &info->spare,
+ info->spare,
count,
iter->cpu_file, 0);
trace_access_unlock(iter->cpu_file);
info->read = 0;
read:
- size = PAGE_SIZE - info->read;
+ size = page_size - info->read;
if (size > count)
size = count;
-
- ret = copy_to_user(ubuf, info->spare + info->read, size);
+ trace_data = ring_buffer_read_page_data(info->spare);
+ ret = copy_to_user(ubuf, trace_data + info->read, size);
if (ret == size)
return -EFAULT;
.spd_release = buffer_spd_release,
};
struct buffer_ref *ref;
+ int page_size;
int entries, i;
ssize_t ret = 0;
return -EBUSY;
#endif
- if (*ppos & (PAGE_SIZE - 1))
+ page_size = ring_buffer_subbuf_size_get(iter->array_buffer->buffer);
+ if (*ppos & (page_size - 1))
return -EINVAL;
- if (len & (PAGE_SIZE - 1)) {
- if (len < PAGE_SIZE)
+ if (len & (page_size - 1)) {
+ if (len < page_size)
return -EINVAL;
- len &= PAGE_MASK;
+ len &= (~(page_size - 1));
}
if (splice_grow_spd(pipe, &spd))
trace_access_lock(iter->cpu_file);
entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file);
- for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) {
+ for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= page_size) {
struct page *page;
int r;
}
ref->cpu = iter->cpu_file;
- r = ring_buffer_read_page(ref->buffer, &ref->page,
+ r = ring_buffer_read_page(ref->buffer, ref->page,
len, iter->cpu_file, 1);
if (r < 0) {
ring_buffer_free_read_page(ref->buffer, ref->cpu,
break;
}
- page = virt_to_page(ref->page);
+ page = virt_to_page(ring_buffer_read_page_data(ref->page));
spd.pages[i] = page;
- spd.partial[i].len = PAGE_SIZE;
+ spd.partial[i].len = page_size;
spd.partial[i].offset = 0;
spd.partial[i].private = (unsigned long)ref;
spd.nr_pages++;
- *ppos += PAGE_SIZE;
+ *ppos += page_size;
entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file);
}
.llseek = default_llseek,
};
+static ssize_t
+buffer_subbuf_size_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = filp->private_data;
+ size_t size;
+ char buf[64];
+ int order;
+ int r;
+
+ order = ring_buffer_subbuf_order_get(tr->array_buffer.buffer);
+ size = (PAGE_SIZE << order) / 1024;
+
+ r = sprintf(buf, "%zd\n", size);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+buffer_subbuf_size_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = filp->private_data;
+ unsigned long val;
+ int old_order;
+ int order;
+ int pages;
+ int ret;
+
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
+ return ret;
+
+ val *= 1024; /* value passed in is in KB */
+
+ pages = DIV_ROUND_UP(val, PAGE_SIZE);
+ order = fls(pages - 1);
+
+ /* limit between 1 and 128 system pages */
+ if (order < 0 || order > 7)
+ return -EINVAL;
+
+ /* Do not allow tracing while changing the order of the ring buffer */
+ tracing_stop_tr(tr);
+
+ old_order = ring_buffer_subbuf_order_get(tr->array_buffer.buffer);
+ if (old_order == order)
+ goto out;
+
+ ret = ring_buffer_subbuf_order_set(tr->array_buffer.buffer, order);
+ if (ret)
+ goto out;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+
+ if (!tr->allocated_snapshot)
+ goto out_max;
+
+ ret = ring_buffer_subbuf_order_set(tr->max_buffer.buffer, order);
+ if (ret) {
+ /* Put back the old order */
+ cnt = ring_buffer_subbuf_order_set(tr->array_buffer.buffer, old_order);
+ if (WARN_ON_ONCE(cnt)) {
+ /*
+ * AARGH! We are left with different orders!
+ * The max buffer is our "snapshot" buffer.
+ * When a tracer needs a snapshot (one of the
+ * latency tracers), it swaps the max buffer
+ * with the saved snap shot. We succeeded to
+ * update the order of the main buffer, but failed to
+ * update the order of the max buffer. But when we tried
+ * to reset the main buffer to the original size, we
+ * failed there too. This is very unlikely to
+ * happen, but if it does, warn and kill all
+ * tracing.
+ */
+ tracing_disabled = 1;
+ }
+ goto out;
+ }
+ out_max:
+#endif
+ (*ppos)++;
+ out:
+ if (ret)
+ cnt = ret;
+ tracing_start_tr(tr);
+ return cnt;
+}
+
+static const struct file_operations buffer_subbuf_size_fops = {
+ .open = tracing_open_generic_tr,
+ .read = buffer_subbuf_size_read,
+ .write = buffer_subbuf_size_write,
+ .release = tracing_release_generic_tr,
+ .llseek = default_llseek,
+};
+
static struct dentry *trace_instance_dir;
static void
return ret;
}
-static struct trace_array *trace_array_create(const char *name)
+static struct trace_array *
+trace_array_create_systems(const char *name, const char *systems)
{
struct trace_array *tr;
int ret;
if (!zalloc_cpumask_var(&tr->pipe_cpumask, GFP_KERNEL))
goto out_free_tr;
+ if (systems) {
+ tr->system_names = kstrdup_const(systems, GFP_KERNEL);
+ if (!tr->system_names)
+ goto out_free_tr;
+ }
+
tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS;
cpumask_copy(tr->tracing_cpumask, cpu_all_mask);
free_trace_buffers(tr);
free_cpumask_var(tr->pipe_cpumask);
free_cpumask_var(tr->tracing_cpumask);
+ kfree_const(tr->system_names);
kfree(tr->name);
kfree(tr);
return ERR_PTR(ret);
}
+static struct trace_array *trace_array_create(const char *name)
+{
+ return trace_array_create_systems(name, NULL);
+}
+
static int instance_mkdir(const char *name)
{
struct trace_array *tr;
/**
* trace_array_get_by_name - Create/Lookup a trace array, given its name.
* @name: The name of the trace array to be looked up/created.
+ * @systems: A list of systems to create event directories for (NULL for all)
*
* Returns pointer to trace array with given name.
* NULL, if it cannot be created.
* trace_array_put() is called, user space can not delete it.
*
*/
-struct trace_array *trace_array_get_by_name(const char *name)
+struct trace_array *trace_array_get_by_name(const char *name, const char *systems)
{
struct trace_array *tr;
goto out_unlock;
}
- tr = trace_array_create(name);
+ tr = trace_array_create_systems(name, systems);
if (IS_ERR(tr))
tr = NULL;
free_cpumask_var(tr->pipe_cpumask);
free_cpumask_var(tr->tracing_cpumask);
+ kfree_const(tr->system_names);
kfree(tr->name);
kfree(tr);
trace_create_file("buffer_percent", TRACE_MODE_WRITE, d_tracer,
tr, &buffer_percent_fops);
+ trace_create_file("buffer_subbuf_size_kb", TRACE_MODE_WRITE, d_tracer,
+ tr, &buffer_subbuf_size_fops);
+
create_trace_options_dir(tr);
#ifdef CONFIG_TRACER_MAX_TRACE
if (IS_ENABLED(CONFIG_TRACER_MAX_TRACE))
do_allocate_snapshot(tok);
- tr = trace_array_get_by_name(tok);
+ tr = trace_array_get_by_name(tok, NULL);
if (!tr) {
pr_warn("Failed to create instance buffer %s\n", curr_str);
continue;
git.samba.org / sfrench / cifs-2.6.git / blobdiff