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: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20260109115411.115270-1-gxxa03070307@gmail.com

diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 8e23580f17549c138733d7b1e1b462f943245726..77555096e4c780e17e9b9043653c0dc3606095dd 100644 (file)
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -46,12 +46,10 @@
  */
 #define DMA_BUF_TRACE(FUNC, ...)                                       \
        do {                                                            \
-               if (FUNC##_enabled()) {                                 \
+               /* Always expose lock if lockdep is enabled */          \
+               if (IS_ENABLED(CONFIG_LOCKDEP) || 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)
 
@@ -795,8 +793,7 @@ int dma_buf_fd(struct dma_buf *dmabuf, int flags)
                return -EINVAL;
 
        fd = FD_ADD(flags, dmabuf->file);
-       if (fd >= 0)
-               DMA_BUF_TRACE(trace_dma_buf_fd, dmabuf, fd);
+       DMA_BUF_TRACE(trace_dma_buf_fd, dmabuf, fd);
 
        return fd;
 }

diff --git a/include/trace/events/dma_buf.h b/include/trace/events/dma_buf.h
index 35f8140095f4fe15a7e32872648ab338c191b586..3bb88d05bcc83bf0160ffc62662b64661180bc38 100644 (file)
--- a/include/trace/events/dma_buf.h
+++ b/include/trace/events/dma_buf.h
@@ -15,15 +15,15 @@ DECLARE_EVENT_CLASS(dma_buf,
        TP_ARGS(dmabuf),
 
        TP_STRUCT__entry(
-               __string(exp_name, dmabuf->exp_name)
-               __field(size_t, size)
-               __field(ino_t, ino)
+               __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;
+               __entry->size   = dmabuf->size;
+               __entry->ino    = dmabuf->file->f_inode->i_ino;
        ),
 
        TP_printk("exp_name=%s size=%zu ino=%lu",
@@ -40,21 +40,21 @@ DECLARE_EVENT_CLASS(dma_buf_attach_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)
+               __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;
+               __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",
@@ -73,17 +73,17 @@ DECLARE_EVENT_CLASS(dma_buf_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)
+               __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;
+               __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",
@@ -137,11 +137,13 @@ DEFINE_EVENT(dma_buf_attach_dev, dma_buf_detach,
        TP_ARGS(dmabuf, attach, is_dynamic, dev)
 );
 
-DEFINE_EVENT(dma_buf_fd, dma_buf_fd,
+DEFINE_EVENT_CONDITION(dma_buf_fd, dma_buf_fd,
 
        TP_PROTO(struct dma_buf *dmabuf, int fd),
 
-       TP_ARGS(dmabuf, fd)
+       TP_ARGS(dmabuf, fd),
+
+       TP_CONDITION(fd >= 0)
 );
 
 DEFINE_EVENT(dma_buf_fd, dma_buf_get,