Re: [PATCH v3 0/5] introduce DAX tracepoint support

From: Ross Zwisler
Date: Mon Dec 19 2016 - 11:51:44 EST


On Thu, Dec 01, 2016 at 09:37:46AM -0700, Ross Zwisler wrote:
> Tracepoints are the standard way to capture debugging and tracing
> information in many parts of the kernel, including the XFS and ext4
> filesystems. This series creates a tracepoint header for FS DAX and add
> the first few DAX tracepoints to the PMD fault handler. This allows the
> tracing for DAX to be done in the same way as the filesystem tracing so
> that developers can look at them together and get a coherent idea of what
> the system is doing.
>
> I do intend to add tracepoints to the normal 4k DAX fault path and to the
> DAX I/O path, but I wanted to get feedback on the PMD tracepoints before I
> went any further.
>
> This series is based on Jan Kara's "dax: Clear dirty bits after flushing
> caches" series:
>
> https://lists.01.org/pipermail/linux-nvdimm/2016-November/007864.html
>
> I've pushed a git tree with this work here:
>
> https://git.kernel.org/cgit/linux/kernel/git/zwisler/linux.git/log/?h=dax_tracepoints_v3
>
> Changes since v2:
> - Dropped "dax: remove leading space from labels" patch. (Jan)
> - Reordered TP_STRUCT__entry() fields so that all the 64 bit entries (for
> 64 bit machines) come first, followed by the 32 bit entries. This
> allows for optimal packing of the entires. (Steve)
> - Fixed 'mask' in trace_print_flags_seq_u64() to be an unsigned long long.
> (Steve)
>
> Ross Zwisler (5):
> tracing: add __print_flags_u64()
> dax: add tracepoint infrastructure, PMD tracing
> dax: update MAINTAINERS entries for FS DAX
> dax: add tracepoints to dax_pmd_load_hole()
> dax: add tracepoints to dax_pmd_insert_mapping()
>
> MAINTAINERS | 5 +-
> fs/dax.c | 56 ++++++++++-----
> include/linux/mm.h | 25 +++++++
> include/linux/pfn_t.h | 6 ++
> include/linux/trace_events.h | 4 ++
> include/trace/events/fs_dax.h | 161 ++++++++++++++++++++++++++++++++++++++++++
> include/trace/trace_events.h | 11 +++
> kernel/trace/trace_output.c | 38 ++++++++++
> 8 files changed, 288 insertions(+), 18 deletions(-)
> create mode 100644 include/trace/events/fs_dax.h

Ping on this series - Dave, were you planning on sending this for v4.10-rc1?