Messages in this thread | | | Date | Wed, 29 Mar 2023 13:27:30 +0100 | From | Vincent Donnefort <> | Subject | Re: [PATCH v2 1/2] ring-buffer: Introducing ring-buffer mapping functions |
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On Wed, Mar 29, 2023 at 08:07:58AM -0400, Steven Rostedt wrote: > On Wed, 29 Mar 2023 07:03:53 -0400 > Steven Rostedt <rostedt@goodmis.org> wrote: > > > struct ring_buffer_meta_page_header { > > #if __BITS_PER_LONG == 64 > > __u64 entries; > > __u64 overrun; > > #else > > __u32 entries; > > __u32 overrun; > > #endif > > __u32 pages_touched; > > __u32 meta_page_size; > > __u32 reader_page; /* page ID for the reader page */ > > __u32 nr_data_pages; /* doesn't take into account the reader_page */ > > }; > > > > BTW, shouldn't the nr_data_pages take into account the reader page? As it > > is part of the array we traverse isn't it? > > Ah, I guess nr_data_pages is the length of the index mapping, not the > array of pages mapped?
Yes correct, data_pages[nr_data_pages] and the reader_page being excluded... which might not be the easiest interface, as the size of the buffer to read depends on if the reader_page has data to be read or not.
> > -- Steve
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