From: Robert Richter Date: Mon, 2 Apr 2012 18:19:16 +0000 (+0200) Subject: perf/x86-ibs: Implement workaround for IBS erratum #420 X-Git-Tag: v3.5-rc1~141^2~25 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c9574fe0bdb9ac9a2698e02a712088ce8431e9f8;p=pandora-kernel.git perf/x86-ibs: Implement workaround for IBS erratum #420 When disabling ibs there might be the case where hardware continuously generates interrupts. This is described in erratum #420 (Instruction- Based Sampling Engine May Generate Interrupt that Cannot Be Cleared). To avoid this we must clear the counter mask first and then clear the enable bit. This patch implements this. See Revision Guide for AMD Family 10h Processors, Publication #41322. Note: We now keep track of the last read ibs config value which is then used to disable ibs. To update the config value we pass now a pointer to the functions reading it. Signed-off-by: Robert Richter Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1333390758-10893-11-git-send-email-robert.richter@amd.com Signed-off-by: Ingo Molnar --- Reading git-diff-tree failed