On Mon, 22 Oct 2018 10:13:48 -0700 Dan Williams <dan.j.willi...@intel.com> wrote:
> [ added Andrew ] > > Patch here: https://lore.kernel.org/patchwork/patch/1002234/ > > On Sun, Oct 21, 2018 at 8:00 AM Sebastien Boisvert > <sebh...@videotron.qc.ca> wrote: > > > > Tracing the event "fs_dax:dax_pmd_insert_mapping" with perf produces this > > warning: > > [fs_dax:dax_pmd_insert_mapping] unknown op '~' > > > > It is printed in process_op (tools/lib/traceevent/event-parse.c) because '~' > > is parsed as a binary operator. > > > > perf reads the format of fs_dax:dax_pmd_insert_mapping ("print fmt") from > > /sys/kernel/debug/tracing/events/fs_dax/dax_pmd_insert_mapping/format . > > > > The format contains: > > > > ~(((u64) ~(~(((1UL) << 12)-1))) > > ^ > > \ interpreted as a binary operator by process_op(). > > > > This part is generated in the declaration of the event class > > dax_pmd_insert_mapping_class in include/trace/events/fs_dax.h : > > > > __print_flags_u64(__entry->pfn_val & PFN_FLAGS_MASK, "|", > > PFN_FLAGS_TRACE), > > > > This patch adds a pair of parentheses in the declaration of PFN_FLAGS_MASK > > to > > make sure that '~' is parsed as a unary operator by perf. > > > > The part of the format that was problematic is now: > > > > ~(((u64) (~(~(((1UL) << 12)-1)))) > > > > Now, all the '~' are parsed as unary operators. > > > > Cc: Dan Williams <dan.j.willi...@intel.com> > > > Acked-by: Dan Williams <dan.j.willi...@intel.com> > I grabbed it, and added cc:stable. But aren't we fixing this in the wrong place? That's a valid expression and if this isn't addressed in perf then we may hit a similar issue elsewhere...
