From: Stephane Eranian Date: Thu, 9 Feb 2012 22:21:06 +0000 (+0100) Subject: perf tools: Enable reading of perf.data files from different ABI rev X-Git-Tag: v3.4-rc1~192^2^2~8 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=69996df486fc3921bbaaa17fca0d68f537f9eabf;p=pandora-kernel.git perf tools: Enable reading of perf.data files from different ABI rev This patch allows perf to process perf.data files generated using an ABI that has a different perf_event_attr struct size, i.e., a different ABI version. The perf_event_attr can be extended, yet perf needs to cope with older perf.data files. Similarly, perf must be able to cope with a perf.data file which is using a newer version of the ABI than what it knows about. This patch adds read_attr(), a routine that reads a perf_event_attr struct from a file incrementally based on its advertised size. If the on-file struct is smaller than what perf knows, then the extra fields are zeroed. If the on-file struct is bigger, then perf only uses what it knows about, the rest is skipped. Signed-off-by: Stephane Eranian Cc: peterz@infradead.org Cc: acme@redhat.com Cc: robert.richter@amd.com Cc: ming.m.lin@intel.com Cc: andi@firstfloor.org Cc: asharma@fb.com Cc: ravitillo@lbl.gov Cc: vweaver1@eecs.utk.edu Cc: khandual@linux.vnet.ibm.com Cc: dsahern@gmail.com Link: http://lkml.kernel.org/r/1328826068-11713-17-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar --- Reading git-diff-tree failed