From: Peter Zijlstra Date: Tue, 2 Mar 2010 18:52:12 +0000 (+0100) Subject: perf, x86: Add PEBS infrastructure X-Git-Tag: v2.6.35-rc1~522^2~236 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ca037701a025334e724e5c61b3b1082940c8b981;p=pandora-kernel.git perf, x86: Add PEBS infrastructure This patch implements support for Intel Precise Event Based Sampling, which is an alternative counter mode in which the counter triggers a hardware assist to collect information on events. The hardware assist takes a trap like snapshot of a subset of the machine registers. This data is written to the Intel Debug-Store, which can be programmed with a data threshold at which to raise a PMI. With the PEBS hardware assist being trap like, the reported IP is always one instruction after the actual instruction that triggered the event. This implements a simple PEBS model that always takes a single PEBS event at a time. This is done so that the interaction with the rest of the system is as expected (freq adjust, period randomization, lbr, callchains, etc.). It adds an ABI element: perf_event_attr::precise, which indicates that we wish to use this (constrained, but precise) mode. Signed-off-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: paulus@samba.org Cc: eranian@google.com Cc: robert.richter@amd.com Cc: fweisbec@gmail.com LKML-Reference: <20100304140100.392111285@chello.nl> Signed-off-by: Ingo Molnar --- Reading git-diff-tree failed