> Exporting the tracepoints is unecessary as far as I can see android must export symbols before adding a whitelist.
> I can't come up with a reason why we should have the file refcount in the > trace logs. > Same for most other places. I can directly observe how refcnt is changing. Then it can be known where the dmabuf was finally released. > Print the dev_name last, it's the external device which attaches to the > DMA-buf. ok. > Additional to that it would be nice to know if the attachment is dynamic or > not. ok. ________________________________ 发件人: Christian König <[email protected]> 发送时间: 2025年11月27日 17:49:09 收件人: Xiang Gao; [email protected]; [email protected]; [email protected] 抄送: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; 高翔 主题: [External Mail]Re: [PATCH v3] dma-buf: add some tracepoints to debug. [外部邮件] 此邮件来源于小米公司外部，请谨慎处理。若对邮件安全性存疑，请将邮件转发给[email protected]进行反馈 On 11/27/25 01:43, Xiang Gao wrote: > From: gaoxiang17 <[email protected]> > > I want to track the status of dmabuf in real time in the production > environment. > But now we can only check it by traversing the fd in the process or > dmabuf_list. > > For example: > binder:2962_2-2962 [005] ...1. 208.453940: dma_buf_export: > exp_name=qcom,system name=(null) size=28672 ino=2580 f_refcnt=2 > binder:2962_2-2962 [005] ...1. 208.453943: dma_buf_fd: > exp_name=qcom,system name=(null) size=28672 ino=2580 fd=9 f_refcnt=2 > binder:2962_2-2962 [005] ...1. 208.453977: dma_buf_mmap_internal: > exp_name=qcom,system name=qcom,system size=28672 ino=2580 f_refcnt=4 > kworker/5:2-194 [005] ...1. 208.460580: dma_buf_put: > exp_name=qcom,system name=ab pid [8176] size=28672 ino=2580 f_refcnt=3 > RenderThread-11305 [007] ...1. 208.599094: dma_buf_get: > exp_name=qcom,system name=ab pid [8176] size=217088 ino=2579 fd=1114 > f_refcnt=7 > RenderThread-11305 [007] ...1. 208.599098: dma_buf_attach: > dev_name=kgsl-3d0 exp_name=qcom,system name=ab pid [8176] size=217088 > ino=2579 f_refcnt=7 > <...>-14 [001] ...1. 208.726359: dma_buf_detach: > dev_name=kgsl-3d0 exp_name=qcom,system name=ab pid [3317] size=217088 > ino=2581 f_refcnt=3 > > Signed-off-by: Xiang Gao <[email protected]> > --- > drivers/dma-buf/dma-buf.c | 57 ++++++++++- > include/trace/events/dma_buf.h | 166 +++++++++++++++++++++++++++++++++ > 2 files changed, 222 insertions(+), 1 deletion(-) > create mode 100644 include/trace/events/dma_buf.h > > diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c > index 2bcf9ceca997..7cef816ddcac 100644 > --- a/drivers/dma-buf/dma-buf.c > +++ b/drivers/dma-buf/dma-buf.c > @@ -35,6 +35,18 @@ > > #include "dma-buf-sysfs-stats.h" > > +#define CREATE_TRACE_POINTS > +#include <trace/events/dma_buf.h> > + > +EXPORT_TRACEPOINT_SYMBOL(dma_buf_export); > +EXPORT_TRACEPOINT_SYMBOL(dma_buf_mmap_internal); > +EXPORT_TRACEPOINT_SYMBOL(dma_buf_mmap); > +EXPORT_TRACEPOINT_SYMBOL(dma_buf_put); > +EXPORT_TRACEPOINT_SYMBOL(dma_buf_attach); > +EXPORT_TRACEPOINT_SYMBOL(dma_buf_detach); > +EXPORT_TRACEPOINT_SYMBOL(dma_buf_fd); > +EXPORT_TRACEPOINT_SYMBOL(dma_buf_get); Exporting the tracepoints is unecessary as far as I can see > + > static inline int is_dma_buf_file(struct file *); > > static DEFINE_MUTEX(dmabuf_list_mutex); > @@ -220,6 +232,11 @@ static int dma_buf_mmap_internal(struct file *file, > struct vm_area_struct *vma) > dmabuf->size >> PAGE_SHIFT) > return -EINVAL; > > + if (trace_dma_buf_mmap_internal_enabled()) { > + guard(spinlock)(&dmabuf->name_lock); > + trace_dma_buf_mmap_internal(dmabuf); > + } > + > return dmabuf->ops->mmap(dmabuf, vma); > } > > @@ -745,6 +762,11 @@ struct dma_buf *dma_buf_export(const struct > dma_buf_export_info *exp_info) > > __dma_buf_list_add(dmabuf); > > + if (trace_dma_buf_export_enabled()) { > + guard(spinlock)(&dmabuf->name_lock); > + trace_dma_buf_export(dmabuf); > + } > + > return dmabuf; > > err_dmabuf: > @@ -779,6 +801,11 @@ int dma_buf_fd(struct dma_buf *dmabuf, int flags) > > fd_install(fd, dmabuf->file); > > + if (trace_dma_buf_fd_enabled()) { > + guard(spinlock)(&dmabuf->name_lock); > + trace_dma_buf_fd(dmabuf, fd); > + } > + > return fd; > } > EXPORT_SYMBOL_NS_GPL(dma_buf_fd, "DMA_BUF"); > @@ -794,6 +821,7 @@ 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); > > @@ -805,7 +833,14 @@ struct dma_buf *dma_buf_get(int fd) > return ERR_PTR(-EINVAL); > } > > - return file->private_data; > + dmabuf = file->private_data; > + > + if (trace_dma_buf_get_enabled()) { > + guard(spinlock)(&dmabuf->name_lock); > + trace_dma_buf_get(dmabuf, fd); > + } > + > + return dmabuf; > } > EXPORT_SYMBOL_NS_GPL(dma_buf_get, "DMA_BUF"); > > @@ -825,6 +860,11 @@ void dma_buf_put(struct dma_buf *dmabuf) > return; > > fput(dmabuf->file); > + > + if (trace_dma_buf_put_enabled()) { > + guard(spinlock)(&dmabuf->name_lock); > + trace_dma_buf_put(dmabuf); > + } > } > EXPORT_SYMBOL_NS_GPL(dma_buf_put, "DMA_BUF"); > > @@ -998,6 +1038,11 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_dynamic_attach, "DMA_BUF"); > struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf, > struct device *dev) > { > + if (trace_dma_buf_attach_enabled()) { > + guard(spinlock)(&dmabuf->name_lock); > + trace_dma_buf_attach(dmabuf, dev); > + } > + > return dma_buf_dynamic_attach(dmabuf, dev, NULL, NULL); > } > EXPORT_SYMBOL_NS_GPL(dma_buf_attach, "DMA_BUF"); > @@ -1023,6 +1068,11 @@ void dma_buf_detach(struct dma_buf *dmabuf, struct > dma_buf_attachment *attach) > if (dmabuf->ops->detach) > dmabuf->ops->detach(dmabuf, attach); > > + if (trace_dma_buf_detach_enabled()) { > + guard(spinlock)(&dmabuf->name_lock); > + trace_dma_buf_detach(dmabuf, attach->dev); > + } > + > kfree(attach); > } > EXPORT_SYMBOL_NS_GPL(dma_buf_detach, "DMA_BUF"); > @@ -1488,6 +1538,11 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct > vm_area_struct *vma, > vma_set_file(vma, dmabuf->file); > vma->vm_pgoff = pgoff; > > + if (trace_dma_buf_mmap_enabled()) { > + guard(spinlock)(&dmabuf->name_lock); > + trace_dma_buf_mmap(dmabuf); > + } > + > return dmabuf->ops->mmap(dmabuf, vma); > } > EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, "DMA_BUF"); > diff --git a/include/trace/events/dma_buf.h b/include/trace/events/dma_buf.h > new file mode 100644 > index 000000000000..fe9da89bacd0 > --- /dev/null > +++ b/include/trace/events/dma_buf.h > @@ -0,0 +1,166 @@ > +/* 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) > + __string(name, dmabuf->name) > + __field(size_t, size) > + __field(ino_t, ino) > + __field(long, f_refcnt) > + ), > + > + TP_fast_assign( > + __assign_str(exp_name); > + __assign_str(name); > + __entry->size = dmabuf->size; > + __entry->ino = dmabuf->file->f_inode->i_ino; > + __entry->f_refcnt = file_count(dmabuf->file); > + ), > + > + TP_printk("exp_name=%s name=%s size=%zu ino=%lu f_refcnt=%ld", > + __get_str(exp_name), > + __get_str(name), > + __entry->size, > + __entry->ino, > + __entry->f_refcnt) I can't come up with a reason why we should have the file refcount in the trace logs. Same for most other places. > +); > + > +DECLARE_EVENT_CLASS(dma_buf_attach_dev, > + > + TP_PROTO(struct dma_buf *dmabuf, struct device *dev), > + > + TP_ARGS(dmabuf, dev), > + > + TP_STRUCT__entry( > + __string(dname, dev_name(dev)) > + __string(exp_name, dmabuf->exp_name) > + __string(name, dmabuf->name) > + __field(size_t, size) > + __field(ino_t, ino) > + __field(long, f_refcnt) > + ), > + > + TP_fast_assign( > + __assign_str(dname); > + __assign_str(exp_name); > + __assign_str(name); > + __entry->size = dmabuf->size; > + __entry->ino = dmabuf->file->f_inode->i_ino; > + __entry->f_refcnt = file_count(dmabuf->file); > + ), > + > + TP_printk("dev_name=%s exp_name=%s name=%s size=%zu ino=%lu > f_refcnt=%ld", > + __get_str(dname), > + __get_str(exp_name), > + __get_str(name), > + __entry->size, > + __entry->ino, > + __entry->f_refcnt) Print the dev_name last, it's the external device which attaches to the DMA-buf. Additional to that it would be nice to know if the attachment is dynamic or not. Regards, Christian. > +); > + > +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) > + __string(name, dmabuf->name) > + __field(size_t, size) > + __field(ino_t, ino) > + __field(int, fd) > + __field(long, f_refcnt) > + ), > + > + TP_fast_assign( > + __assign_str(exp_name); > + __assign_str(name); > + __entry->size = dmabuf->size; > + __entry->ino = dmabuf->file->f_inode->i_ino; > + __entry->fd = fd; > + __entry->f_refcnt = file_count(dmabuf->file); > + ), > + > + TP_printk("exp_name=%s name=%s size=%zu ino=%lu fd=%d f_refcnt=%ld", > + __get_str(exp_name), > + __get_str(name), > + __entry->size, > + __entry->ino, > + __entry->fd, > + __entry->f_refcnt) > +); > + > +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_attach, > + > + TP_PROTO(struct dma_buf *dmabuf, struct device *dev), > + > + TP_ARGS(dmabuf, dev) > +); > + > +DEFINE_EVENT(dma_buf_attach_dev, dma_buf_detach, > + > + TP_PROTO(struct dma_buf *dmabuf, struct device *dev), > + > + TP_ARGS(dmabuf, 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>
