From: Alexander Shishkin Date: Wed, 14 Jan 2015 12:18:10 +0000 (+0200) Subject: perf: Add data_{offset,size} to user_page X-Git-Tag: omap-for-v4.2/o2_dc~146^2~36 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e8c6deac69629c0cb97c3d3272f8631ef17f8f0f;p=pandora-kernel.git perf: Add data_{offset,size} to user_page Currently, the actual perf ring buffer is one page into the mmap area, following the user page and the userspace follows this convention. This patch adds data_{offset,size} fields to user_page that can be used by userspace instead for locating perf data in the mmap area. This is also helpful when mapping existing or shared buffers if their size is not known in advance. Right now, it is made to follow the existing convention that data_offset == PAGE_SIZE and data_offset + data_size == mmap_size. Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Borislav Petkov Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kaixu Xia Cc: Linus Torvalds Cc: Mike Galbraith Cc: Paul Mackerras Cc: Robert Richter Cc: Stephane Eranian Cc: Thomas Gleixner Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: kan.liang@intel.com Cc: markus.t.metzger@intel.com Cc: mathieu.poirier@linaro.org Link: http://lkml.kernel.org/r/1421237903-181015-2-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- Reading git-diff-tree failed