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Commit d038b12c authored by Stephane Eranian's avatar Stephane Eranian Committed by Ingo Molnar
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perf: Fix Pentium4 raw event validation 



This patch fixes some issues with raw event validation on
Pentium 4 (Netburst) based processors.

As I was testing libpfm4 Netburst support, I ran into two
problems in the p4_validate_raw_event() function:

   - the shared field must be checked ONLY when HT is on
   - the binding to ESCR register was missing

The second item was causing raw events to not be encoded
correctly compared to generic PMU events.

With this patch, I can now pass Netburst events to libpfm4
examples and get meaningful results:

  $ task -e global_power_events:running:u  noploop 1
  noploop for 1 seconds
  3,206,304,898 global_power_events:running

Signed-off-by: default avatarStephane Eranian <eranian@google.com>
Acked-by: default avatarCyrill Gorcunov <gorcunov@openvz.org>
Cc: peterz@infradead.org
Cc: paulus@samba.org
Cc: davem@davemloft.net
Cc: fweisbec@gmail.com
Cc: perfmon2-devel@lists.sf.net
Cc: eranian@gmail.com
Cc: robert.richter@amd.com
Cc: acme@redhat.com
Cc: gorcunov@gmail.com
Cc: ming.m.lin@intel.com
LKML-Reference: <4d3efb2f.1252d80a.1a80.ffffc83f@mx.google.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 88d4f0db

arch/x86/kernel/cpu/perf_event_p4.c

+10 −2
Original line number Diff line number Diff line
@@ -682,7 +682,7 @@ static int p4_validate_raw_event(struct perf_event *event) 
	 * if an event is shared accross the logical threads

	 * the user needs special permissions to be able to use it

	 */

	if (p4_event_bind_map[v].shared) {

	if (p4_ht_active() && p4_event_bind_map[v].shared) {

		if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN))

			return -EACCES;

	}
@@ -727,7 +727,8 @@ static int p4_hw_config(struct perf_event *event) 
		event->hw.config = p4_set_ht_bit(event->hw.config);



	if (event->attr.type == PERF_TYPE_RAW) {



		struct p4_event_bind *bind;

		unsigned int esel;

		/*

		 * Clear bits we reserve to be managed by kernel itself

		 * and never allowed from a user space
@@ -743,6 +744,13 @@ static int p4_hw_config(struct perf_event *event) 
		 * bits since we keep additional info here (for cache events and etc)

		 */

		event->hw.config |= event->attr.config;

		bind = p4_config_get_bind(event->attr.config);

		if (!bind) {

			rc = -EINVAL;

			goto out;

		}

		esel = P4_OPCODE_ESEL(bind->opcode);

		event->hw.config |= p4_config_pack_cccr(P4_CCCR_ESEL(esel));

	}



	rc = x86_setup_perfctr(event);