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: Xiang Gao <gaoxiang17@xiaomi.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20251218062853.819744-1-gxxa03070307@gmail.com
Signed-off-by: Christian König <christian.koenig@amd.com>
This commit is contained in:
gaoxiang17 2025-12-18 14:28:53 +08:00 committed by Christian König
parent b440baf355
commit 281a226314
2 changed files with 206 additions and 2 deletions

View File

@ -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");

View File

@ -0,0 +1,157 @@
/* 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>