Commit 281a2263 authored by gaoxiang17's avatar gaoxiang17 Committed by Christian König
Browse files

dma-buf: add some tracepoints to debug. 



Since we can only inspect dmabuf by iterating over process FDs or the
dmabuf_list, we need to add our own tracepoints to track its status in
real time in production.

For example:
   binder:3016_1-3102    [006] ...1.   255.126521: dma_buf_export: exp_name=qcom,system size=12685312 ino=2738
   binder:3016_1-3102    [006] ...1.   255.126528: dma_buf_fd: exp_name=qcom,system size=12685312 ino=2738 fd=8
   binder:3016_1-3102    [006] ...1.   255.126642: dma_buf_mmap_internal: exp_name=qcom,system size=28672 ino=2739
     kworker/6:1-86      [006] ...1.   255.127194: dma_buf_put: exp_name=qcom,system size=12685312 ino=2738
    RenderThread-9293    [006] ...1.   316.618179: dma_buf_get: exp_name=qcom,system size=12771328 ino=2762 fd=176
    RenderThread-9293    [006] ...1.   316.618195: dma_buf_dynamic_attach: exp_name=qcom,system size=12771328 ino=2762 attachment:ffffff880a18dd00 is_dynamic=0 dev_name=kgsl-3d0
    RenderThread-9293    [006] ...1.   318.878220: dma_buf_detach: exp_name=qcom,system size=12771328 ino=2762 attachment:ffffff880a18dd00 is_dynamic=0 dev_name=kgsl-3d0

Signed-off-by: default avatarXiang Gao <gaoxiang17@xiaomi.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20251218062853.819744-1-gxxa03070307@gmail.com


Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
parent b440baf3

drivers/dma-buf/dma-buf.c

+49 −2
Original line number Diff line number Diff line
@@ -35,6 +35,28 @@ 


#include "dma-buf-sysfs-stats.h"



#define CREATE_TRACE_POINTS

#include <trace/events/dma_buf.h>



/*

 * dmabuf->name must be accessed with holding dmabuf->name_lock.

 * we need to take the lock around the tracepoint call itself where

 * it is called in the code.

 *

 * Note: FUNC##_enabled() is a static branch that will only

 *       be set when the trace event is enabled.

 */

#define DMA_BUF_TRACE(FUNC, ...)					\

	do {								\

		if (FUNC##_enabled()) {					\

			guard(spinlock)(&dmabuf->name_lock);		\

			FUNC(__VA_ARGS__);				\

		} else if (IS_ENABLED(CONFIG_LOCKDEP)) {		\

			/* Expose this lock when lockdep is enabled */	\

			guard(spinlock)(&dmabuf->name_lock);		\

		}							\

	} while (0)



/* Wrapper to hide the sg_table page link from the importer */

struct dma_buf_sg_table_wrapper {

	struct sg_table *original;
@@ -226,6 +248,8 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma) 
	    dmabuf->size >> PAGE_SHIFT)

		return -EINVAL;



	DMA_BUF_TRACE(trace_dma_buf_mmap_internal, dmabuf);



	return dmabuf->ops->mmap(dmabuf, vma);

}
@@ -751,6 +775,8 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) 


	__dma_buf_list_add(dmabuf);



	DMA_BUF_TRACE(trace_dma_buf_export, dmabuf);



	return dmabuf;



err_dmabuf:
@@ -774,10 +800,16 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_export, "DMA_BUF"); 
 */

int dma_buf_fd(struct dma_buf *dmabuf, int flags)

{

	int fd;



	if (!dmabuf || !dmabuf->file)

		return -EINVAL;



	return FD_ADD(flags, dmabuf->file);

	fd = FD_ADD(flags, dmabuf->file);

	if (fd >= 0)

		DMA_BUF_TRACE(trace_dma_buf_fd, dmabuf, fd);



	return fd;

}

EXPORT_SYMBOL_NS_GPL(dma_buf_fd, "DMA_BUF");
@@ -792,6 +824,7 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_fd, "DMA_BUF"); 
struct dma_buf *dma_buf_get(int fd)

{

	struct file *file;

	struct dma_buf *dmabuf;



	file = fget(fd);
@@ -803,7 +836,11 @@ struct dma_buf *dma_buf_get(int fd) 
		return ERR_PTR(-EINVAL);

	}



	return file->private_data;

	dmabuf = file->private_data;



	DMA_BUF_TRACE(trace_dma_buf_get, dmabuf, fd);



	return dmabuf;

}

EXPORT_SYMBOL_NS_GPL(dma_buf_get, "DMA_BUF");
@@ -823,6 +860,8 @@ void dma_buf_put(struct dma_buf *dmabuf) 
		return;



	fput(dmabuf->file);



	DMA_BUF_TRACE(trace_dma_buf_put, dmabuf);

}

EXPORT_SYMBOL_NS_GPL(dma_buf_put, "DMA_BUF");
@@ -1015,6 +1054,9 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, 
	list_add(&attach->node, &dmabuf->attachments);

	dma_resv_unlock(dmabuf->resv);



	DMA_BUF_TRACE(trace_dma_buf_dynamic_attach, dmabuf, attach,

		dma_buf_attachment_is_dynamic(attach), dev);



	return attach;



err_attach:
@@ -1059,6 +1101,9 @@ void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) 
	if (dmabuf->ops->detach)

		dmabuf->ops->detach(dmabuf, attach);



	DMA_BUF_TRACE(trace_dma_buf_detach, dmabuf, attach,

		dma_buf_attachment_is_dynamic(attach), attach->dev);



	kfree(attach);

}

EXPORT_SYMBOL_NS_GPL(dma_buf_detach, "DMA_BUF");
@@ -1525,6 +1570,8 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma, 
	vma_set_file(vma, dmabuf->file);

	vma->vm_pgoff = pgoff;



	DMA_BUF_TRACE(trace_dma_buf_mmap, dmabuf);



	return dmabuf->ops->mmap(dmabuf, vma);

}

EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, "DMA_BUF");

include/trace/events/dma_buf.h

0 → 100644
+157 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#undef TRACE_SYSTEM

#define TRACE_SYSTEM dma_buf



#if !defined(_TRACE_DMA_BUF_H) || defined(TRACE_HEADER_MULTI_READ)

#define _TRACE_DMA_BUF_H



#include <linux/dma-buf.h>

#include <linux/tracepoint.h>



DECLARE_EVENT_CLASS(dma_buf,



	TP_PROTO(struct dma_buf *dmabuf),



	TP_ARGS(dmabuf),



	TP_STRUCT__entry(

		__string(exp_name, dmabuf->exp_name)

		__field(size_t, size)

		__field(ino_t, ino)

	),



	TP_fast_assign(

		__assign_str(exp_name);

		__entry->size = dmabuf->size;

		__entry->ino = dmabuf->file->f_inode->i_ino;

	),



	TP_printk("exp_name=%s size=%zu ino=%lu",

		  __get_str(exp_name),

		  __entry->size,

		  __entry->ino)

);



DECLARE_EVENT_CLASS(dma_buf_attach_dev,



	TP_PROTO(struct dma_buf *dmabuf, struct dma_buf_attachment *attach,

		bool is_dynamic, struct device *dev),



	TP_ARGS(dmabuf, attach, is_dynamic, dev),



	TP_STRUCT__entry(

		__string(dev_name, dev_name(dev))

		__string(exp_name, dmabuf->exp_name)

		__field(size_t, size)

		__field(ino_t, ino)

		__field(struct dma_buf_attachment *, attach)

		__field(bool, is_dynamic)

	),



	TP_fast_assign(

		__assign_str(dev_name);

		__assign_str(exp_name);

		__entry->size = dmabuf->size;

		__entry->ino = dmabuf->file->f_inode->i_ino;

		__entry->is_dynamic = is_dynamic;

		__entry->attach = attach;

	),



	TP_printk("exp_name=%s size=%zu ino=%lu attachment:%p is_dynamic=%d dev_name=%s",

		  __get_str(exp_name),

		  __entry->size,

		  __entry->ino,

		  __entry->attach,

		  __entry->is_dynamic,

		  __get_str(dev_name))

);



DECLARE_EVENT_CLASS(dma_buf_fd,



	TP_PROTO(struct dma_buf *dmabuf, int fd),



	TP_ARGS(dmabuf, fd),



	TP_STRUCT__entry(

		__string(exp_name, dmabuf->exp_name)

		__field(size_t, size)

		__field(ino_t, ino)

		__field(int, fd)

	),



	TP_fast_assign(

		__assign_str(exp_name);

		__entry->size = dmabuf->size;

		__entry->ino = dmabuf->file->f_inode->i_ino;

		__entry->fd = fd;

	),



	TP_printk("exp_name=%s size=%zu ino=%lu fd=%d",

		  __get_str(exp_name),

		  __entry->size,

		  __entry->ino,

		  __entry->fd)

);



DEFINE_EVENT(dma_buf, dma_buf_export,



	TP_PROTO(struct dma_buf *dmabuf),



	TP_ARGS(dmabuf)

);



DEFINE_EVENT(dma_buf, dma_buf_mmap_internal,



	TP_PROTO(struct dma_buf *dmabuf),



	TP_ARGS(dmabuf)

);



DEFINE_EVENT(dma_buf, dma_buf_mmap,



	TP_PROTO(struct dma_buf *dmabuf),



	TP_ARGS(dmabuf)

);



DEFINE_EVENT(dma_buf, dma_buf_put,



	TP_PROTO(struct dma_buf *dmabuf),



	TP_ARGS(dmabuf)

);



DEFINE_EVENT(dma_buf_attach_dev, dma_buf_dynamic_attach,



	TP_PROTO(struct dma_buf *dmabuf, struct dma_buf_attachment *attach,

		bool is_dynamic, struct device *dev),



	TP_ARGS(dmabuf, attach, is_dynamic, dev)

);



DEFINE_EVENT(dma_buf_attach_dev, dma_buf_detach,



	TP_PROTO(struct dma_buf *dmabuf, struct dma_buf_attachment *attach,

		bool is_dynamic, struct device *dev),



	TP_ARGS(dmabuf, attach, is_dynamic, dev)

);



DEFINE_EVENT(dma_buf_fd, dma_buf_fd,



	TP_PROTO(struct dma_buf *dmabuf, int fd),



	TP_ARGS(dmabuf, fd)

);



DEFINE_EVENT(dma_buf_fd, dma_buf_get,



	TP_PROTO(struct dma_buf *dmabuf, int fd),



	TP_ARGS(dmabuf, fd)

);



#endif /* _TRACE_DMA_BUF_H */



/* This part must be outside protection */

#include <trace/define_trace.h>