On 11/27/25 15:05, 高翔 wrote: >> Exporting the tracepoints is unecessary as far as I can see > > android must export symbols before adding a whitelist.
Hui? Why would you add those symbols to any 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. The refcnt is manipulated outside of the DMA-buf code by the filesystem layer. As far as I can see it is meaningless here. Regards, Christian. > > >> 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> >
