linux/arch/powerpc/kernel/power5-pmu.c
Paul Mackerras 6984efb692 perf_counter: powerpc: Fix event alternative code generation on POWER5/5+
Commit ef923214 ("perf_counter: powerpc: use u64 for event
codes internally") introduced a bug where the return value from
function find_alternative_bdecode gets put into a u64 variable
and later tested to see if it is < 0.  The effect is that we
get extra, bogus event code alternatives on POWER5 and POWER5+,
leading to error messages such as "oops compute_mmcr failed"
being printed and counters not counting properly.

This fixes it by using s64 for the return type of
find_alternative_bdecode and for the local variable that the
caller puts the value in.  It also makes the event argument a
u64 on POWER5+ for consistency.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Cc: Stephane Eranian <eranian@googlemail.com>
LKML-Reference: <18982.17586.666132.90983@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-03 11:49:52 +02:00

571 lines
15 KiB
C

/*
* Performance counter support for POWER5 (not POWER5++) processors.
*
* Copyright 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/kernel.h>
#include <linux/perf_counter.h>
#include <asm/reg.h>
/*
* Bits in event code for POWER5 (not POWER5++)
*/
#define PM_PMC_SH 20 /* PMC number (1-based) for direct events */
#define PM_PMC_MSK 0xf
#define PM_PMC_MSKS (PM_PMC_MSK << PM_PMC_SH)
#define PM_UNIT_SH 16 /* TTMMUX number and setting - unit select */
#define PM_UNIT_MSK 0xf
#define PM_BYTE_SH 12 /* Byte number of event bus to use */
#define PM_BYTE_MSK 7
#define PM_GRS_SH 8 /* Storage subsystem mux select */
#define PM_GRS_MSK 7
#define PM_BUSEVENT_MSK 0x80 /* Set if event uses event bus */
#define PM_PMCSEL_MSK 0x7f
/* Values in PM_UNIT field */
#define PM_FPU 0
#define PM_ISU0 1
#define PM_IFU 2
#define PM_ISU1 3
#define PM_IDU 4
#define PM_ISU0_ALT 6
#define PM_GRS 7
#define PM_LSU0 8
#define PM_LSU1 0xc
#define PM_LASTUNIT 0xc
/*
* Bits in MMCR1 for POWER5
*/
#define MMCR1_TTM0SEL_SH 62
#define MMCR1_TTM1SEL_SH 60
#define MMCR1_TTM2SEL_SH 58
#define MMCR1_TTM3SEL_SH 56
#define MMCR1_TTMSEL_MSK 3
#define MMCR1_TD_CP_DBG0SEL_SH 54
#define MMCR1_TD_CP_DBG1SEL_SH 52
#define MMCR1_TD_CP_DBG2SEL_SH 50
#define MMCR1_TD_CP_DBG3SEL_SH 48
#define MMCR1_GRS_L2SEL_SH 46
#define MMCR1_GRS_L2SEL_MSK 3
#define MMCR1_GRS_L3SEL_SH 44
#define MMCR1_GRS_L3SEL_MSK 3
#define MMCR1_GRS_MCSEL_SH 41
#define MMCR1_GRS_MCSEL_MSK 7
#define MMCR1_GRS_FABSEL_SH 39
#define MMCR1_GRS_FABSEL_MSK 3
#define MMCR1_PMC1_ADDER_SEL_SH 35
#define MMCR1_PMC2_ADDER_SEL_SH 34
#define MMCR1_PMC3_ADDER_SEL_SH 33
#define MMCR1_PMC4_ADDER_SEL_SH 32
#define MMCR1_PMC1SEL_SH 25
#define MMCR1_PMC2SEL_SH 17
#define MMCR1_PMC3SEL_SH 9
#define MMCR1_PMC4SEL_SH 1
#define MMCR1_PMCSEL_SH(n) (MMCR1_PMC1SEL_SH - (n) * 8)
#define MMCR1_PMCSEL_MSK 0x7f
/*
* Bits in MMCRA
*/
/*
* Layout of constraint bits:
* 6666555555555544444444443333333333222222222211111111110000000000
* 3210987654321098765432109876543210987654321098765432109876543210
* <><>[ ><><>< ><> [ >[ >[ >< >< >< >< ><><><><><><>
* T0T1 NC G0G1G2 G3 UC PS1PS2 B0 B1 B2 B3 P6P5P4P3P2P1
*
* T0 - TTM0 constraint
* 54-55: TTM0SEL value (0=FPU, 2=IFU, 3=ISU1) 0xc0_0000_0000_0000
*
* T1 - TTM1 constraint
* 52-53: TTM1SEL value (0=IDU, 3=GRS) 0x30_0000_0000_0000
*
* NC - number of counters
* 51: NC error 0x0008_0000_0000_0000
* 48-50: number of events needing PMC1-4 0x0007_0000_0000_0000
*
* G0..G3 - GRS mux constraints
* 46-47: GRS_L2SEL value
* 44-45: GRS_L3SEL value
* 41-44: GRS_MCSEL value
* 39-40: GRS_FABSEL value
* Note that these match up with their bit positions in MMCR1
*
* UC - unit constraint: can't have all three of FPU|IFU|ISU1, ISU0, IDU|GRS
* 37: UC3 error 0x20_0000_0000
* 36: FPU|IFU|ISU1 events needed 0x10_0000_0000
* 35: ISU0 events needed 0x08_0000_0000
* 34: IDU|GRS events needed 0x04_0000_0000
*
* PS1
* 33: PS1 error 0x2_0000_0000
* 31-32: count of events needing PMC1/2 0x1_8000_0000
*
* PS2
* 30: PS2 error 0x4000_0000
* 28-29: count of events needing PMC3/4 0x3000_0000
*
* B0
* 24-27: Byte 0 event source 0x0f00_0000
* Encoding as for the event code
*
* B1, B2, B3
* 20-23, 16-19, 12-15: Byte 1, 2, 3 event sources
*
* P1..P6
* 0-11: Count of events needing PMC1..PMC6
*/
static const int grsel_shift[8] = {
MMCR1_GRS_L2SEL_SH, MMCR1_GRS_L2SEL_SH, MMCR1_GRS_L2SEL_SH,
MMCR1_GRS_L3SEL_SH, MMCR1_GRS_L3SEL_SH, MMCR1_GRS_L3SEL_SH,
MMCR1_GRS_MCSEL_SH, MMCR1_GRS_FABSEL_SH
};
/* Masks and values for using events from the various units */
static u64 unit_cons[PM_LASTUNIT+1][2] = {
[PM_FPU] = { 0xc0002000000000ull, 0x00001000000000ull },
[PM_ISU0] = { 0x00002000000000ull, 0x00000800000000ull },
[PM_ISU1] = { 0xc0002000000000ull, 0xc0001000000000ull },
[PM_IFU] = { 0xc0002000000000ull, 0x80001000000000ull },
[PM_IDU] = { 0x30002000000000ull, 0x00000400000000ull },
[PM_GRS] = { 0x30002000000000ull, 0x30000400000000ull },
};
static int power5_get_constraint(u64 event, u64 *maskp, u64 *valp)
{
int pmc, byte, unit, sh;
int bit, fmask;
u64 mask = 0, value = 0;
int grp = -1;
pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
if (pmc) {
if (pmc > 6)
return -1;
sh = (pmc - 1) * 2;
mask |= 2 << sh;
value |= 1 << sh;
if (pmc <= 4)
grp = (pmc - 1) >> 1;
else if (event != 0x500009 && event != 0x600005)
return -1;
}
if (event & PM_BUSEVENT_MSK) {
unit = (event >> PM_UNIT_SH) & PM_UNIT_MSK;
if (unit > PM_LASTUNIT)
return -1;
if (unit == PM_ISU0_ALT)
unit = PM_ISU0;
mask |= unit_cons[unit][0];
value |= unit_cons[unit][1];
byte = (event >> PM_BYTE_SH) & PM_BYTE_MSK;
if (byte >= 4) {
if (unit != PM_LSU1)
return -1;
/* Map LSU1 low word (bytes 4-7) to unit LSU1+1 */
++unit;
byte &= 3;
}
if (unit == PM_GRS) {
bit = event & 7;
fmask = (bit == 6)? 7: 3;
sh = grsel_shift[bit];
mask |= (u64)fmask << sh;
value |= (u64)((event >> PM_GRS_SH) & fmask) << sh;
}
/*
* Bus events on bytes 0 and 2 can be counted
* on PMC1/2; bytes 1 and 3 on PMC3/4.
*/
if (!pmc)
grp = byte & 1;
/* Set byte lane select field */
mask |= 0xfULL << (24 - 4 * byte);
value |= (u64)unit << (24 - 4 * byte);
}
if (grp == 0) {
/* increment PMC1/2 field */
mask |= 0x200000000ull;
value |= 0x080000000ull;
} else if (grp == 1) {
/* increment PMC3/4 field */
mask |= 0x40000000ull;
value |= 0x10000000ull;
}
if (pmc < 5) {
/* need a counter from PMC1-4 set */
mask |= 0x8000000000000ull;
value |= 0x1000000000000ull;
}
*maskp = mask;
*valp = value;
return 0;
}
#define MAX_ALT 3 /* at most 3 alternatives for any event */
static const unsigned int event_alternatives[][MAX_ALT] = {
{ 0x120e4, 0x400002 }, /* PM_GRP_DISP_REJECT */
{ 0x410c7, 0x441084 }, /* PM_THRD_L2MISS_BOTH_CYC */
{ 0x100005, 0x600005 }, /* PM_RUN_CYC */
{ 0x100009, 0x200009, 0x500009 }, /* PM_INST_CMPL */
{ 0x300009, 0x400009 }, /* PM_INST_DISP */
};
/*
* Scan the alternatives table for a match and return the
* index into the alternatives table if found, else -1.
*/
static int find_alternative(u64 event)
{
int i, j;
for (i = 0; i < ARRAY_SIZE(event_alternatives); ++i) {
if (event < event_alternatives[i][0])
break;
for (j = 0; j < MAX_ALT && event_alternatives[i][j]; ++j)
if (event == event_alternatives[i][j])
return i;
}
return -1;
}
static const unsigned char bytedecode_alternatives[4][4] = {
/* PMC 1 */ { 0x21, 0x23, 0x25, 0x27 },
/* PMC 2 */ { 0x07, 0x17, 0x0e, 0x1e },
/* PMC 3 */ { 0x20, 0x22, 0x24, 0x26 },
/* PMC 4 */ { 0x07, 0x17, 0x0e, 0x1e }
};
/*
* Some direct events for decodes of event bus byte 3 have alternative
* PMCSEL values on other counters. This returns the alternative
* event code for those that do, or -1 otherwise.
*/
static s64 find_alternative_bdecode(u64 event)
{
int pmc, altpmc, pp, j;
pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
if (pmc == 0 || pmc > 4)
return -1;
altpmc = 5 - pmc; /* 1 <-> 4, 2 <-> 3 */
pp = event & PM_PMCSEL_MSK;
for (j = 0; j < 4; ++j) {
if (bytedecode_alternatives[pmc - 1][j] == pp) {
return (event & ~(PM_PMC_MSKS | PM_PMCSEL_MSK)) |
(altpmc << PM_PMC_SH) |
bytedecode_alternatives[altpmc - 1][j];
}
}
return -1;
}
static int power5_get_alternatives(u64 event, unsigned int flags, u64 alt[])
{
int i, j, nalt = 1;
s64 ae;
alt[0] = event;
nalt = 1;
i = find_alternative(event);
if (i >= 0) {
for (j = 0; j < MAX_ALT; ++j) {
ae = event_alternatives[i][j];
if (ae && ae != event)
alt[nalt++] = ae;
}
} else {
ae = find_alternative_bdecode(event);
if (ae > 0)
alt[nalt++] = ae;
}
return nalt;
}
/*
* Map of which direct events on which PMCs are marked instruction events.
* Indexed by PMCSEL value, bit i (LE) set if PMC i is a marked event.
* Bit 0 is set if it is marked for all PMCs.
* The 0x80 bit indicates a byte decode PMCSEL value.
*/
static unsigned char direct_event_is_marked[0x28] = {
0, /* 00 */
0x1f, /* 01 PM_IOPS_CMPL */
0x2, /* 02 PM_MRK_GRP_DISP */
0xe, /* 03 PM_MRK_ST_CMPL, PM_MRK_ST_GPS, PM_MRK_ST_CMPL_INT */
0, /* 04 */
0x1c, /* 05 PM_MRK_BRU_FIN, PM_MRK_INST_FIN, PM_MRK_CRU_FIN */
0x80, /* 06 */
0x80, /* 07 */
0, 0, 0,/* 08 - 0a */
0x18, /* 0b PM_THRESH_TIMEO, PM_MRK_GRP_TIMEO */
0, /* 0c */
0x80, /* 0d */
0x80, /* 0e */
0, /* 0f */
0, /* 10 */
0x14, /* 11 PM_MRK_GRP_BR_REDIR, PM_MRK_GRP_IC_MISS */
0, /* 12 */
0x10, /* 13 PM_MRK_GRP_CMPL */
0x1f, /* 14 PM_GRP_MRK, PM_MRK_{FXU,FPU,LSU}_FIN */
0x2, /* 15 PM_MRK_GRP_ISSUED */
0x80, /* 16 */
0x80, /* 17 */
0, 0, 0, 0, 0,
0x80, /* 1d */
0x80, /* 1e */
0, /* 1f */
0x80, /* 20 */
0x80, /* 21 */
0x80, /* 22 */
0x80, /* 23 */
0x80, /* 24 */
0x80, /* 25 */
0x80, /* 26 */
0x80, /* 27 */
};
/*
* Returns 1 if event counts things relating to marked instructions
* and thus needs the MMCRA_SAMPLE_ENABLE bit set, or 0 if not.
*/
static int power5_marked_instr_event(u64 event)
{
int pmc, psel;
int bit, byte, unit;
u32 mask;
pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
psel = event & PM_PMCSEL_MSK;
if (pmc >= 5)
return 0;
bit = -1;
if (psel < sizeof(direct_event_is_marked)) {
if (direct_event_is_marked[psel] & (1 << pmc))
return 1;
if (direct_event_is_marked[psel] & 0x80)
bit = 4;
else if (psel == 0x08)
bit = pmc - 1;
else if (psel == 0x10)
bit = 4 - pmc;
else if (psel == 0x1b && (pmc == 1 || pmc == 3))
bit = 4;
} else if ((psel & 0x58) == 0x40)
bit = psel & 7;
if (!(event & PM_BUSEVENT_MSK))
return 0;
byte = (event >> PM_BYTE_SH) & PM_BYTE_MSK;
unit = (event >> PM_UNIT_SH) & PM_UNIT_MSK;
if (unit == PM_LSU0) {
/* byte 1 bits 0-7, byte 2 bits 0,2-4,6 */
mask = 0x5dff00;
} else if (unit == PM_LSU1 && byte >= 4) {
byte -= 4;
/* byte 4 bits 1,3,5,7, byte 5 bits 6-7, byte 7 bits 0-4,6 */
mask = 0x5f00c0aa;
} else
return 0;
return (mask >> (byte * 8 + bit)) & 1;
}
static int power5_compute_mmcr(u64 event[], int n_ev,
unsigned int hwc[], u64 mmcr[])
{
u64 mmcr1 = 0;
u64 mmcra = 0;
unsigned int pmc, unit, byte, psel;
unsigned int ttm, grp;
int i, isbus, bit, grsel;
unsigned int pmc_inuse = 0;
unsigned int pmc_grp_use[2];
unsigned char busbyte[4];
unsigned char unituse[16];
int ttmuse;
if (n_ev > 6)
return -1;
/* First pass to count resource use */
pmc_grp_use[0] = pmc_grp_use[1] = 0;
memset(busbyte, 0, sizeof(busbyte));
memset(unituse, 0, sizeof(unituse));
for (i = 0; i < n_ev; ++i) {
pmc = (event[i] >> PM_PMC_SH) & PM_PMC_MSK;
if (pmc) {
if (pmc > 6)
return -1;
if (pmc_inuse & (1 << (pmc - 1)))
return -1;
pmc_inuse |= 1 << (pmc - 1);
/* count 1/2 vs 3/4 use */
if (pmc <= 4)
++pmc_grp_use[(pmc - 1) >> 1];
}
if (event[i] & PM_BUSEVENT_MSK) {
unit = (event[i] >> PM_UNIT_SH) & PM_UNIT_MSK;
byte = (event[i] >> PM_BYTE_SH) & PM_BYTE_MSK;
if (unit > PM_LASTUNIT)
return -1;
if (unit == PM_ISU0_ALT)
unit = PM_ISU0;
if (byte >= 4) {
if (unit != PM_LSU1)
return -1;
++unit;
byte &= 3;
}
if (!pmc)
++pmc_grp_use[byte & 1];
if (busbyte[byte] && busbyte[byte] != unit)
return -1;
busbyte[byte] = unit;
unituse[unit] = 1;
}
}
if (pmc_grp_use[0] > 2 || pmc_grp_use[1] > 2)
return -1;
/*
* Assign resources and set multiplexer selects.
*
* PM_ISU0 can go either on TTM0 or TTM1, but that's the only
* choice we have to deal with.
*/
if (unituse[PM_ISU0] &
(unituse[PM_FPU] | unituse[PM_IFU] | unituse[PM_ISU1])) {
unituse[PM_ISU0_ALT] = 1; /* move ISU to TTM1 */
unituse[PM_ISU0] = 0;
}
/* Set TTM[01]SEL fields. */
ttmuse = 0;
for (i = PM_FPU; i <= PM_ISU1; ++i) {
if (!unituse[i])
continue;
if (ttmuse++)
return -1;
mmcr1 |= (u64)i << MMCR1_TTM0SEL_SH;
}
ttmuse = 0;
for (; i <= PM_GRS; ++i) {
if (!unituse[i])
continue;
if (ttmuse++)
return -1;
mmcr1 |= (u64)(i & 3) << MMCR1_TTM1SEL_SH;
}
if (ttmuse > 1)
return -1;
/* Set byte lane select fields, TTM[23]SEL and GRS_*SEL. */
for (byte = 0; byte < 4; ++byte) {
unit = busbyte[byte];
if (!unit)
continue;
if (unit == PM_ISU0 && unituse[PM_ISU0_ALT]) {
/* get ISU0 through TTM1 rather than TTM0 */
unit = PM_ISU0_ALT;
} else if (unit == PM_LSU1 + 1) {
/* select lower word of LSU1 for this byte */
mmcr1 |= 1ull << (MMCR1_TTM3SEL_SH + 3 - byte);
}
ttm = unit >> 2;
mmcr1 |= (u64)ttm << (MMCR1_TD_CP_DBG0SEL_SH - 2 * byte);
}
/* Second pass: assign PMCs, set PMCxSEL and PMCx_ADDER_SEL fields */
for (i = 0; i < n_ev; ++i) {
pmc = (event[i] >> PM_PMC_SH) & PM_PMC_MSK;
unit = (event[i] >> PM_UNIT_SH) & PM_UNIT_MSK;
byte = (event[i] >> PM_BYTE_SH) & PM_BYTE_MSK;
psel = event[i] & PM_PMCSEL_MSK;
isbus = event[i] & PM_BUSEVENT_MSK;
if (!pmc) {
/* Bus event or any-PMC direct event */
for (pmc = 0; pmc < 4; ++pmc) {
if (pmc_inuse & (1 << pmc))
continue;
grp = (pmc >> 1) & 1;
if (isbus) {
if (grp == (byte & 1))
break;
} else if (pmc_grp_use[grp] < 2) {
++pmc_grp_use[grp];
break;
}
}
pmc_inuse |= 1 << pmc;
} else if (pmc <= 4) {
/* Direct event */
--pmc;
if ((psel == 8 || psel == 0x10) && isbus && (byte & 2))
/* add events on higher-numbered bus */
mmcr1 |= 1ull << (MMCR1_PMC1_ADDER_SEL_SH - pmc);
} else {
/* Instructions or run cycles on PMC5/6 */
--pmc;
}
if (isbus && unit == PM_GRS) {
bit = psel & 7;
grsel = (event[i] >> PM_GRS_SH) & PM_GRS_MSK;
mmcr1 |= (u64)grsel << grsel_shift[bit];
}
if (power5_marked_instr_event(event[i]))
mmcra |= MMCRA_SAMPLE_ENABLE;
if (pmc <= 3)
mmcr1 |= psel << MMCR1_PMCSEL_SH(pmc);
hwc[i] = pmc;
}
/* Return MMCRx values */
mmcr[0] = 0;
if (pmc_inuse & 1)
mmcr[0] = MMCR0_PMC1CE;
if (pmc_inuse & 0x3e)
mmcr[0] |= MMCR0_PMCjCE;
mmcr[1] = mmcr1;
mmcr[2] = mmcra;
return 0;
}
static void power5_disable_pmc(unsigned int pmc, u64 mmcr[])
{
if (pmc <= 3)
mmcr[1] &= ~(0x7fUL << MMCR1_PMCSEL_SH(pmc));
}
static int power5_generic_events[] = {
[PERF_COUNT_CPU_CYCLES] = 0xf,
[PERF_COUNT_INSTRUCTIONS] = 0x100009,
[PERF_COUNT_CACHE_REFERENCES] = 0x4c1090, /* LD_REF_L1 */
[PERF_COUNT_CACHE_MISSES] = 0x3c1088, /* LD_MISS_L1 */
[PERF_COUNT_BRANCH_INSTRUCTIONS] = 0x230e4, /* BR_ISSUED */
[PERF_COUNT_BRANCH_MISSES] = 0x230e5, /* BR_MPRED_CR */
};
struct power_pmu power5_pmu = {
.n_counter = 6,
.max_alternatives = MAX_ALT,
.add_fields = 0x7000090000555ull,
.test_adder = 0x3000490000000ull,
.compute_mmcr = power5_compute_mmcr,
.get_constraint = power5_get_constraint,
.get_alternatives = power5_get_alternatives,
.disable_pmc = power5_disable_pmc,
.n_generic = ARRAY_SIZE(power5_generic_events),
.generic_events = power5_generic_events,
};