linux/arch/powerpc/include/asm/perf_counter.h
Paul Mackerras ef923214a4 perf_counter: powerpc: use u64 for event codes internally
Although the perf_counter API allows 63-bit raw event codes,
internally in the powerpc back-end we had been using 32-bit
event codes.  This expands them to 64 bits so that we can add
bits for specifying threshold start/stop events and instruction
sampling modes later.

This also corrects the return value of can_go_on_limited_pmc;
we were returning an event code rather than just a 0/1 value in
some circumstances. That didn't particularly matter while event
codes were 32-bit, but now that event codes are 64-bit it
might, so this fixes it.

[ Impact: extend PowerPC perfcounter interfaces from u32 to u64 ]

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18955.36874.472452.353104@drongo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-15 16:38:55 +02:00

83 lines
3.3 KiB
C

/*
* Performance counter support - PowerPC-specific definitions.
*
* Copyright 2008-2009 Paul Mackerras, IBM Corporation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/types.h>
#define MAX_HWCOUNTERS 8
#define MAX_EVENT_ALTERNATIVES 8
#define MAX_LIMITED_HWCOUNTERS 2
/*
* This struct provides the constants and functions needed to
* describe the PMU on a particular POWER-family CPU.
*/
struct power_pmu {
int n_counter;
int max_alternatives;
u64 add_fields;
u64 test_adder;
int (*compute_mmcr)(u64 events[], int n_ev,
unsigned int hwc[], u64 mmcr[]);
int (*get_constraint)(u64 event, u64 *mskp, u64 *valp);
int (*get_alternatives)(u64 event, unsigned int flags,
u64 alt[]);
void (*disable_pmc)(unsigned int pmc, u64 mmcr[]);
int (*limited_pmc_event)(u64 event);
int limited_pmc5_6; /* PMC5 and PMC6 have limited function */
int n_generic;
int *generic_events;
};
extern struct power_pmu *ppmu;
/*
* Values for flags to get_alternatives()
*/
#define PPMU_LIMITED_PMC_OK 1 /* can put this on a limited PMC */
#define PPMU_LIMITED_PMC_REQD 2 /* have to put this on a limited PMC */
#define PPMU_ONLY_COUNT_RUN 4 /* only counting in run state */
/*
* The power_pmu.get_constraint function returns a 64-bit value and
* a 64-bit mask that express the constraints between this event and
* other events.
*
* The value and mask are divided up into (non-overlapping) bitfields
* of three different types:
*
* Select field: this expresses the constraint that some set of bits
* in MMCR* needs to be set to a specific value for this event. For a
* select field, the mask contains 1s in every bit of the field, and
* the value contains a unique value for each possible setting of the
* MMCR* bits. The constraint checking code will ensure that two events
* that set the same field in their masks have the same value in their
* value dwords.
*
* Add field: this expresses the constraint that there can be at most
* N events in a particular class. A field of k bits can be used for
* N <= 2^(k-1) - 1. The mask has the most significant bit of the field
* set (and the other bits 0), and the value has only the least significant
* bit of the field set. In addition, the 'add_fields' and 'test_adder'
* in the struct power_pmu for this processor come into play. The
* add_fields value contains 1 in the LSB of the field, and the
* test_adder contains 2^(k-1) - 1 - N in the field.
*
* NAND field: this expresses the constraint that you may not have events
* in all of a set of classes. (For example, on PPC970, you can't select
* events from the FPU, ISU and IDU simultaneously, although any two are
* possible.) For N classes, the field is N+1 bits wide, and each class
* is assigned one bit from the least-significant N bits. The mask has
* only the most-significant bit set, and the value has only the bit
* for the event's class set. The test_adder has the least significant
* bit set in the field.
*
* If an event is not subject to the constraint expressed by a particular
* field, then it will have 0 in both the mask and value for that field.
*/