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core-book3s.c
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core-book3s.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Performance event support - powerpc architecture code
*
* Copyright 2008-2009 Paul Mackerras, IBM Corporation.
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/sched/clock.h>
#include <linux/perf_event.h>
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <linux/uaccess.h>
#include <asm/reg.h>
#include <asm/pmc.h>
#include <asm/machdep.h>
#include <asm/firmware.h>
#include <asm/ptrace.h>
#include <asm/code-patching.h>
#ifdef CONFIG_PPC64
#include "internal.h"
#endif
#define BHRB_MAX_ENTRIES 32
#define BHRB_TARGET 0x0000000000000002
#define BHRB_PREDICTION 0x0000000000000001
#define BHRB_EA 0xFFFFFFFFFFFFFFFCUL
struct cpu_hw_events {
int n_events;
int n_percpu;
int disabled;
int n_added;
int n_limited;
u8 pmcs_enabled;
struct perf_event *event[MAX_HWEVENTS];
u64 events[MAX_HWEVENTS];
unsigned int flags[MAX_HWEVENTS];
struct mmcr_regs mmcr;
struct perf_event *limited_counter[MAX_LIMITED_HWCOUNTERS];
u8 limited_hwidx[MAX_LIMITED_HWCOUNTERS];
u64 alternatives[MAX_HWEVENTS][MAX_EVENT_ALTERNATIVES];
unsigned long amasks[MAX_HWEVENTS][MAX_EVENT_ALTERNATIVES];
unsigned long avalues[MAX_HWEVENTS][MAX_EVENT_ALTERNATIVES];
unsigned int txn_flags;
int n_txn_start;
/* BHRB bits */
u64 bhrb_filter; /* BHRB HW branch filter */
unsigned int bhrb_users;
void *bhrb_context;
struct perf_branch_stack bhrb_stack;
struct perf_branch_entry bhrb_entries[BHRB_MAX_ENTRIES];
u64 ic_init;
};
static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events);
static struct power_pmu *ppmu;
/*
* Normally, to ignore kernel events we set the FCS (freeze counters
* in supervisor mode) bit in MMCR0, but if the kernel runs with the
* hypervisor bit set in the MSR, or if we are running on a processor
* where the hypervisor bit is forced to 1 (as on Apple G5 processors),
* then we need to use the FCHV bit to ignore kernel events.
*/
static unsigned int freeze_events_kernel = MMCR0_FCS;
/*
* 32-bit doesn't have MMCRA but does have an MMCR2,
* and a few other names are different.
* Also 32-bit doesn't have MMCR3, SIER2 and SIER3.
* Define them as zero knowing that any code path accessing
* these registers (via mtspr/mfspr) are done under ppmu flag
* check for PPMU_ARCH_31 and we will not enter that code path
* for 32-bit.
*/
#ifdef CONFIG_PPC32
#define MMCR0_FCHV 0
#define MMCR0_PMCjCE MMCR0_PMCnCE
#define MMCR0_FC56 0
#define MMCR0_PMAO 0
#define MMCR0_EBE 0
#define MMCR0_BHRBA 0
#define MMCR0_PMCC 0
#define MMCR0_PMCC_U6 0
#define SPRN_MMCRA SPRN_MMCR2
#define SPRN_MMCR3 0
#define SPRN_SIER2 0
#define SPRN_SIER3 0
#define MMCRA_SAMPLE_ENABLE 0
#define MMCRA_BHRB_DISABLE 0
#define MMCR0_PMCCEXT 0
static inline unsigned long perf_ip_adjust(struct pt_regs *regs)
{
return 0;
}
static inline void perf_get_data_addr(struct perf_event *event, struct pt_regs *regs, u64 *addrp) { }
static inline u32 perf_get_misc_flags(struct pt_regs *regs)
{
return 0;
}
static inline void perf_read_regs(struct pt_regs *regs)
{
regs->result = 0;
}
static inline int siar_valid(struct pt_regs *regs)
{
return 1;
}
static bool is_ebb_event(struct perf_event *event) { return false; }
static int ebb_event_check(struct perf_event *event) { return 0; }
static void ebb_event_add(struct perf_event *event) { }
static void ebb_switch_out(unsigned long mmcr0) { }
static unsigned long ebb_switch_in(bool ebb, struct cpu_hw_events *cpuhw)
{
return cpuhw->mmcr.mmcr0;
}
static inline void power_pmu_bhrb_enable(struct perf_event *event) {}
static inline void power_pmu_bhrb_disable(struct perf_event *event) {}
static void power_pmu_sched_task(struct perf_event_context *ctx, bool sched_in) {}
static inline void power_pmu_bhrb_read(struct perf_event *event, struct cpu_hw_events *cpuhw) {}
static void pmao_restore_workaround(bool ebb) { }
#endif /* CONFIG_PPC32 */
bool is_sier_available(void)
{
if (!ppmu)
return false;
if (ppmu->flags & PPMU_HAS_SIER)
return true;
return false;
}
static bool regs_use_siar(struct pt_regs *regs)
{
/*
* When we take a performance monitor exception the regs are setup
* using perf_read_regs() which overloads some fields, in particular
* regs->result to tell us whether to use SIAR.
*
* However if the regs are from another exception, eg. a syscall, then
* they have not been setup using perf_read_regs() and so regs->result
* is something random.
*/
return ((TRAP(regs) == 0xf00) && regs->result);
}
/*
* Things that are specific to 64-bit implementations.
*/
#ifdef CONFIG_PPC64
static inline unsigned long perf_ip_adjust(struct pt_regs *regs)
{
unsigned long mmcra = regs->dsisr;
if ((ppmu->flags & PPMU_HAS_SSLOT) && (mmcra & MMCRA_SAMPLE_ENABLE)) {
unsigned long slot = (mmcra & MMCRA_SLOT) >> MMCRA_SLOT_SHIFT;
if (slot > 1)
return 4 * (slot - 1);
}
return 0;
}
/*
* The user wants a data address recorded.
* If we're not doing instruction sampling, give them the SDAR
* (sampled data address). If we are doing instruction sampling, then
* only give them the SDAR if it corresponds to the instruction
* pointed to by SIAR; this is indicated by the [POWER6_]MMCRA_SDSYNC, the
* [POWER7P_]MMCRA_SDAR_VALID bit in MMCRA, or the SDAR_VALID bit in SIER.
*/
static inline void perf_get_data_addr(struct perf_event *event, struct pt_regs *regs, u64 *addrp)
{
unsigned long mmcra = regs->dsisr;
bool sdar_valid;
if (ppmu->flags & PPMU_HAS_SIER)
sdar_valid = regs->dar & SIER_SDAR_VALID;
else {
unsigned long sdsync;
if (ppmu->flags & PPMU_SIAR_VALID)
sdsync = POWER7P_MMCRA_SDAR_VALID;
else if (ppmu->flags & PPMU_ALT_SIPR)
sdsync = POWER6_MMCRA_SDSYNC;
else if (ppmu->flags & PPMU_NO_SIAR)
sdsync = MMCRA_SAMPLE_ENABLE;
else
sdsync = MMCRA_SDSYNC;
sdar_valid = mmcra & sdsync;
}
if (!(mmcra & MMCRA_SAMPLE_ENABLE) || sdar_valid)
*addrp = mfspr(SPRN_SDAR);
if (is_kernel_addr(mfspr(SPRN_SDAR)) && event->attr.exclude_kernel)
*addrp = 0;
}
static bool regs_sihv(struct pt_regs *regs)
{
unsigned long sihv = MMCRA_SIHV;
if (ppmu->flags & PPMU_HAS_SIER)
return !!(regs->dar & SIER_SIHV);
if (ppmu->flags & PPMU_ALT_SIPR)
sihv = POWER6_MMCRA_SIHV;
return !!(regs->dsisr & sihv);
}
static bool regs_sipr(struct pt_regs *regs)
{
unsigned long sipr = MMCRA_SIPR;
if (ppmu->flags & PPMU_HAS_SIER)
return !!(regs->dar & SIER_SIPR);
if (ppmu->flags & PPMU_ALT_SIPR)
sipr = POWER6_MMCRA_SIPR;
return !!(regs->dsisr & sipr);
}
static inline u32 perf_flags_from_msr(struct pt_regs *regs)
{
if (regs->msr & MSR_PR)
return PERF_RECORD_MISC_USER;
if ((regs->msr & MSR_HV) && freeze_events_kernel != MMCR0_FCHV)
return PERF_RECORD_MISC_HYPERVISOR;
return PERF_RECORD_MISC_KERNEL;
}
static inline u32 perf_get_misc_flags(struct pt_regs *regs)
{
bool use_siar = regs_use_siar(regs);
if (!use_siar)
return perf_flags_from_msr(regs);
/*
* If we don't have flags in MMCRA, rather than using
* the MSR, we intuit the flags from the address in
* SIAR which should give slightly more reliable
* results
*/
if (ppmu->flags & PPMU_NO_SIPR) {
unsigned long siar = mfspr(SPRN_SIAR);
if (is_kernel_addr(siar))
return PERF_RECORD_MISC_KERNEL;
return PERF_RECORD_MISC_USER;
}
/* PR has priority over HV, so order below is important */
if (regs_sipr(regs))
return PERF_RECORD_MISC_USER;
if (regs_sihv(regs) && (freeze_events_kernel != MMCR0_FCHV))
return PERF_RECORD_MISC_HYPERVISOR;
return PERF_RECORD_MISC_KERNEL;
}
/*
* Overload regs->dsisr to store MMCRA so we only need to read it once
* on each interrupt.
* Overload regs->dar to store SIER if we have it.
* Overload regs->result to specify whether we should use the MSR (result
* is zero) or the SIAR (result is non zero).
*/
static inline void perf_read_regs(struct pt_regs *regs)
{
unsigned long mmcra = mfspr(SPRN_MMCRA);
int marked = mmcra & MMCRA_SAMPLE_ENABLE;
int use_siar;
regs->dsisr = mmcra;
if (ppmu->flags & PPMU_HAS_SIER)
regs->dar = mfspr(SPRN_SIER);
/*
* If this isn't a PMU exception (eg a software event) the SIAR is
* not valid. Use pt_regs.
*
* If it is a marked event use the SIAR.
*
* If the PMU doesn't update the SIAR for non marked events use
* pt_regs.
*
* If the PMU has HV/PR flags then check to see if they
* place the exception in userspace. If so, use pt_regs. In
* continuous sampling mode the SIAR and the PMU exception are
* not synchronised, so they may be many instructions apart.
* This can result in confusing backtraces. We still want
* hypervisor samples as well as samples in the kernel with
* interrupts off hence the userspace check.
*/
if (TRAP(regs) != 0xf00)
use_siar = 0;
else if ((ppmu->flags & PPMU_NO_SIAR))
use_siar = 0;
else if (marked)
use_siar = 1;
else if ((ppmu->flags & PPMU_NO_CONT_SAMPLING))
use_siar = 0;
else if (!(ppmu->flags & PPMU_NO_SIPR) && regs_sipr(regs))
use_siar = 0;
else
use_siar = 1;
regs->result = use_siar;
}
/*
* On processors like P7+ that have the SIAR-Valid bit, marked instructions
* must be sampled only if the SIAR-valid bit is set.
*
* For unmarked instructions and for processors that don't have the SIAR-Valid
* bit, assume that SIAR is valid.
*/
static inline int siar_valid(struct pt_regs *regs)
{
unsigned long mmcra = regs->dsisr;
int marked = mmcra & MMCRA_SAMPLE_ENABLE;
if (marked) {
if (ppmu->flags & PPMU_HAS_SIER)
return regs->dar & SIER_SIAR_VALID;
if (ppmu->flags & PPMU_SIAR_VALID)
return mmcra & POWER7P_MMCRA_SIAR_VALID;
}
return 1;
}
/* Reset all possible BHRB entries */
static void power_pmu_bhrb_reset(void)
{
asm volatile(PPC_CLRBHRB);
}
static void power_pmu_bhrb_enable(struct perf_event *event)
{
struct cpu_hw_events *cpuhw = this_cpu_ptr(&cpu_hw_events);
if (!ppmu->bhrb_nr)
return;
/* Clear BHRB if we changed task context to avoid data leaks */
if (event->ctx->task && cpuhw->bhrb_context != event->ctx) {
power_pmu_bhrb_reset();
cpuhw->bhrb_context = event->ctx;
}
cpuhw->bhrb_users++;
perf_sched_cb_inc(event->ctx->pmu);
}
static void power_pmu_bhrb_disable(struct perf_event *event)
{
struct cpu_hw_events *cpuhw = this_cpu_ptr(&cpu_hw_events);
if (!ppmu->bhrb_nr)
return;
WARN_ON_ONCE(!cpuhw->bhrb_users);
cpuhw->bhrb_users--;
perf_sched_cb_dec(event->ctx->pmu);
if (!cpuhw->disabled && !cpuhw->bhrb_users) {
/* BHRB cannot be turned off when other
* events are active on the PMU.
*/
/* avoid stale pointer */
cpuhw->bhrb_context = NULL;
}
}
/* Called from ctxsw to prevent one process's branch entries to
* mingle with the other process's entries during context switch.
*/
static void power_pmu_sched_task(struct perf_event_context *ctx, bool sched_in)
{
if (!ppmu->bhrb_nr)
return;
if (sched_in)
power_pmu_bhrb_reset();
}
/* Calculate the to address for a branch */
static __u64 power_pmu_bhrb_to(u64 addr)
{
unsigned int instr;
__u64 target;
if (is_kernel_addr(addr)) {
if (copy_from_kernel_nofault(&instr, (void *)addr,
sizeof(instr)))
return 0;
return branch_target((struct ppc_inst *)&instr);
}
/* Userspace: need copy instruction here then translate it */
if (copy_from_user_nofault(&instr, (unsigned int __user *)addr,
sizeof(instr)))
return 0;
target = branch_target((struct ppc_inst *)&instr);
if ((!target) || (instr & BRANCH_ABSOLUTE))
return target;
/* Translate relative branch target from kernel to user address */
return target - (unsigned long)&instr + addr;
}
/* Processing BHRB entries */
static void power_pmu_bhrb_read(struct perf_event *event, struct cpu_hw_events *cpuhw)
{
u64 val;
u64 addr;
int r_index, u_index, pred;
r_index = 0;
u_index = 0;
while (r_index < ppmu->bhrb_nr) {
/* Assembly read function */
val = read_bhrb(r_index++);
if (!val)
/* Terminal marker: End of valid BHRB entries */
break;
else {
addr = val & BHRB_EA;
pred = val & BHRB_PREDICTION;
if (!addr)
/* invalid entry */
continue;
/*
* BHRB rolling buffer could very much contain the kernel
* addresses at this point. Check the privileges before
* exporting it to userspace (avoid exposure of regions
* where we could have speculative execution)
* Incase of ISA v3.1, BHRB will capture only user-space
* addresses, hence include a check before filtering code
*/
if (!(ppmu->flags & PPMU_ARCH_31) &&
is_kernel_addr(addr) && event->attr.exclude_kernel)
continue;
/* Branches are read most recent first (ie. mfbhrb 0 is
* the most recent branch).
* There are two types of valid entries:
* 1) a target entry which is the to address of a
* computed goto like a blr,bctr,btar. The next
* entry read from the bhrb will be branch
* corresponding to this target (ie. the actual
* blr/bctr/btar instruction).
* 2) a from address which is an actual branch. If a
* target entry proceeds this, then this is the
* matching branch for that target. If this is not
* following a target entry, then this is a branch
* where the target is given as an immediate field
* in the instruction (ie. an i or b form branch).
* In this case we need to read the instruction from
* memory to determine the target/to address.
*/
if (val & BHRB_TARGET) {
/* Target branches use two entries
* (ie. computed gotos/XL form)
*/
cpuhw->bhrb_entries[u_index].to = addr;
cpuhw->bhrb_entries[u_index].mispred = pred;
cpuhw->bhrb_entries[u_index].predicted = ~pred;
/* Get from address in next entry */
val = read_bhrb(r_index++);
addr = val & BHRB_EA;
if (val & BHRB_TARGET) {
/* Shouldn't have two targets in a
row.. Reset index and try again */
r_index--;
addr = 0;
}
cpuhw->bhrb_entries[u_index].from = addr;
} else {
/* Branches to immediate field
(ie I or B form) */
cpuhw->bhrb_entries[u_index].from = addr;
cpuhw->bhrb_entries[u_index].to =
power_pmu_bhrb_to(addr);
cpuhw->bhrb_entries[u_index].mispred = pred;
cpuhw->bhrb_entries[u_index].predicted = ~pred;
}
u_index++;
}
}
cpuhw->bhrb_stack.nr = u_index;
cpuhw->bhrb_stack.hw_idx = -1ULL;
return;
}
static bool is_ebb_event(struct perf_event *event)
{
/*
* This could be a per-PMU callback, but we'd rather avoid the cost. We
* check that the PMU supports EBB, meaning those that don't can still
* use bit 63 of the event code for something else if they wish.
*/
return (ppmu->flags & PPMU_ARCH_207S) &&
((event->attr.config >> PERF_EVENT_CONFIG_EBB_SHIFT) & 1);
}
static int ebb_event_check(struct perf_event *event)
{
struct perf_event *leader = event->group_leader;
/* Event and group leader must agree on EBB */
if (is_ebb_event(leader) != is_ebb_event(event))
return -EINVAL;
if (is_ebb_event(event)) {
if (!(event->attach_state & PERF_ATTACH_TASK))
return -EINVAL;
if (!leader->attr.pinned || !leader->attr.exclusive)
return -EINVAL;
if (event->attr.freq ||
event->attr.inherit ||
event->attr.sample_type ||
event->attr.sample_period ||
event->attr.enable_on_exec)
return -EINVAL;
}
return 0;
}
static void ebb_event_add(struct perf_event *event)
{
if (!is_ebb_event(event) || current->thread.used_ebb)
return;
/*
* IFF this is the first time we've added an EBB event, set
* PMXE in the user MMCR0 so we can detect when it's cleared by
* userspace. We need this so that we can context switch while
* userspace is in the EBB handler (where PMXE is 0).
*/
current->thread.used_ebb = 1;
current->thread.mmcr0 |= MMCR0_PMXE;
}
static void ebb_switch_out(unsigned long mmcr0)
{
if (!(mmcr0 & MMCR0_EBE))
return;
current->thread.siar = mfspr(SPRN_SIAR);
current->thread.sier = mfspr(SPRN_SIER);
current->thread.sdar = mfspr(SPRN_SDAR);
current->thread.mmcr0 = mmcr0 & MMCR0_USER_MASK;
current->thread.mmcr2 = mfspr(SPRN_MMCR2) & MMCR2_USER_MASK;
if (ppmu->flags & PPMU_ARCH_31) {
current->thread.mmcr3 = mfspr(SPRN_MMCR3);
current->thread.sier2 = mfspr(SPRN_SIER2);
current->thread.sier3 = mfspr(SPRN_SIER3);
}
}
static unsigned long ebb_switch_in(bool ebb, struct cpu_hw_events *cpuhw)
{
unsigned long mmcr0 = cpuhw->mmcr.mmcr0;
if (!ebb)
goto out;
/* Enable EBB and read/write to all 6 PMCs and BHRB for userspace */
mmcr0 |= MMCR0_EBE | MMCR0_BHRBA | MMCR0_PMCC_U6;
/*
* Add any bits from the user MMCR0, FC or PMAO. This is compatible
* with pmao_restore_workaround() because we may add PMAO but we never
* clear it here.
*/
mmcr0 |= current->thread.mmcr0;
/*
* Be careful not to set PMXE if userspace had it cleared. This is also
* compatible with pmao_restore_workaround() because it has already
* cleared PMXE and we leave PMAO alone.
*/
if (!(current->thread.mmcr0 & MMCR0_PMXE))
mmcr0 &= ~MMCR0_PMXE;
mtspr(SPRN_SIAR, current->thread.siar);
mtspr(SPRN_SIER, current->thread.sier);
mtspr(SPRN_SDAR, current->thread.sdar);
/*
* Merge the kernel & user values of MMCR2. The semantics we implement
* are that the user MMCR2 can set bits, ie. cause counters to freeze,
* but not clear bits. If a task wants to be able to clear bits, ie.
* unfreeze counters, it should not set exclude_xxx in its events and
* instead manage the MMCR2 entirely by itself.
*/
mtspr(SPRN_MMCR2, cpuhw->mmcr.mmcr2 | current->thread.mmcr2);
if (ppmu->flags & PPMU_ARCH_31) {
mtspr(SPRN_MMCR3, current->thread.mmcr3);
mtspr(SPRN_SIER2, current->thread.sier2);
mtspr(SPRN_SIER3, current->thread.sier3);
}
out:
return mmcr0;
}
static void pmao_restore_workaround(bool ebb)
{
unsigned pmcs[6];
if (!cpu_has_feature(CPU_FTR_PMAO_BUG))
return;
/*
* On POWER8E there is a hardware defect which affects the PMU context
* switch logic, ie. power_pmu_disable/enable().
*
* When a counter overflows PMXE is cleared and FC/PMAO is set in MMCR0
* by the hardware. Sometime later the actual PMU exception is
* delivered.
*
* If we context switch, or simply disable/enable, the PMU prior to the
* exception arriving, the exception will be lost when we clear PMAO.
*
* When we reenable the PMU, we will write the saved MMCR0 with PMAO
* set, and this _should_ generate an exception. However because of the
* defect no exception is generated when we write PMAO, and we get
* stuck with no counters counting but no exception delivered.
*
* The workaround is to detect this case and tweak the hardware to
* create another pending PMU exception.
*
* We do that by setting up PMC6 (cycles) for an imminent overflow and
* enabling the PMU. That causes a new exception to be generated in the
* chip, but we don't take it yet because we have interrupts hard
* disabled. We then write back the PMU state as we want it to be seen
* by the exception handler. When we reenable interrupts the exception
* handler will be called and see the correct state.
*
* The logic is the same for EBB, except that the exception is gated by
* us having interrupts hard disabled as well as the fact that we are
* not in userspace. The exception is finally delivered when we return
* to userspace.
*/
/* Only if PMAO is set and PMAO_SYNC is clear */
if ((current->thread.mmcr0 & (MMCR0_PMAO | MMCR0_PMAO_SYNC)) != MMCR0_PMAO)
return;
/* If we're doing EBB, only if BESCR[GE] is set */
if (ebb && !(current->thread.bescr & BESCR_GE))
return;
/*
* We are already soft-disabled in power_pmu_enable(). We need to hard
* disable to actually prevent the PMU exception from firing.
*/
hard_irq_disable();
/*
* This is a bit gross, but we know we're on POWER8E and have 6 PMCs.
* Using read/write_pmc() in a for loop adds 12 function calls and
* almost doubles our code size.
*/
pmcs[0] = mfspr(SPRN_PMC1);
pmcs[1] = mfspr(SPRN_PMC2);
pmcs[2] = mfspr(SPRN_PMC3);
pmcs[3] = mfspr(SPRN_PMC4);
pmcs[4] = mfspr(SPRN_PMC5);
pmcs[5] = mfspr(SPRN_PMC6);
/* Ensure all freeze bits are unset */
mtspr(SPRN_MMCR2, 0);
/* Set up PMC6 to overflow in one cycle */
mtspr(SPRN_PMC6, 0x7FFFFFFE);
/* Enable exceptions and unfreeze PMC6 */
mtspr(SPRN_MMCR0, MMCR0_PMXE | MMCR0_PMCjCE | MMCR0_PMAO);
/* Now we need to refreeze and restore the PMCs */
mtspr(SPRN_MMCR0, MMCR0_FC | MMCR0_PMAO);
mtspr(SPRN_PMC1, pmcs[0]);
mtspr(SPRN_PMC2, pmcs[1]);
mtspr(SPRN_PMC3, pmcs[2]);
mtspr(SPRN_PMC4, pmcs[3]);
mtspr(SPRN_PMC5, pmcs[4]);
mtspr(SPRN_PMC6, pmcs[5]);
}
#endif /* CONFIG_PPC64 */
static void perf_event_interrupt(struct pt_regs *regs);
/*
* Read one performance monitor counter (PMC).
*/
static unsigned long read_pmc(int idx)
{
unsigned long val;
switch (idx) {
case 1:
val = mfspr(SPRN_PMC1);
break;
case 2:
val = mfspr(SPRN_PMC2);
break;
case 3:
val = mfspr(SPRN_PMC3);
break;
case 4:
val = mfspr(SPRN_PMC4);
break;
case 5:
val = mfspr(SPRN_PMC5);
break;
case 6:
val = mfspr(SPRN_PMC6);
break;
#ifdef CONFIG_PPC64
case 7:
val = mfspr(SPRN_PMC7);
break;
case 8:
val = mfspr(SPRN_PMC8);
break;
#endif /* CONFIG_PPC64 */
default:
printk(KERN_ERR "oops trying to read PMC%d\n", idx);
val = 0;
}
return val;
}
/*
* Write one PMC.
*/
static void write_pmc(int idx, unsigned long val)
{
switch (idx) {
case 1:
mtspr(SPRN_PMC1, val);
break;
case 2:
mtspr(SPRN_PMC2, val);
break;
case 3:
mtspr(SPRN_PMC3, val);
break;
case 4:
mtspr(SPRN_PMC4, val);
break;
case 5:
mtspr(SPRN_PMC5, val);
break;
case 6:
mtspr(SPRN_PMC6, val);
break;
#ifdef CONFIG_PPC64
case 7:
mtspr(SPRN_PMC7, val);
break;
case 8:
mtspr(SPRN_PMC8, val);
break;
#endif /* CONFIG_PPC64 */
default:
printk(KERN_ERR "oops trying to write PMC%d\n", idx);
}
}
static int any_pmc_overflown(struct cpu_hw_events *cpuhw)
{
int i, idx;
for (i = 0; i < cpuhw->n_events; i++) {
idx = cpuhw->event[i]->hw.idx;
if ((idx) && ((int)read_pmc(idx) < 0))
return idx;
}
return 0;
}
/* Called from sysrq_handle_showregs() */
void perf_event_print_debug(void)
{
unsigned long sdar, sier, flags;
u32 pmcs[MAX_HWEVENTS];
int i;
if (!ppmu) {
pr_info("Performance monitor hardware not registered.\n");
return;
}
if (!ppmu->n_counter)
return;
local_irq_save(flags);
pr_info("CPU: %d PMU registers, ppmu = %s n_counters = %d",
smp_processor_id(), ppmu->name, ppmu->n_counter);
for (i = 0; i < ppmu->n_counter; i++)
pmcs[i] = read_pmc(i + 1);
for (; i < MAX_HWEVENTS; i++)
pmcs[i] = 0xdeadbeef;
pr_info("PMC1: %08x PMC2: %08x PMC3: %08x PMC4: %08x\n",
pmcs[0], pmcs[1], pmcs[2], pmcs[3]);
if (ppmu->n_counter > 4)
pr_info("PMC5: %08x PMC6: %08x PMC7: %08x PMC8: %08x\n",
pmcs[4], pmcs[5], pmcs[6], pmcs[7]);
pr_info("MMCR0: %016lx MMCR1: %016lx MMCRA: %016lx\n",
mfspr(SPRN_MMCR0), mfspr(SPRN_MMCR1), mfspr(SPRN_MMCRA));
sdar = sier = 0;
#ifdef CONFIG_PPC64
sdar = mfspr(SPRN_SDAR);
if (ppmu->flags & PPMU_HAS_SIER)
sier = mfspr(SPRN_SIER);
if (ppmu->flags & PPMU_ARCH_207S) {
pr_info("MMCR2: %016lx EBBHR: %016lx\n",
mfspr(SPRN_MMCR2), mfspr(SPRN_EBBHR));
pr_info("EBBRR: %016lx BESCR: %016lx\n",
mfspr(SPRN_EBBRR), mfspr(SPRN_BESCR));
}
if (ppmu->flags & PPMU_ARCH_31) {
pr_info("MMCR3: %016lx SIER2: %016lx SIER3: %016lx\n",
mfspr(SPRN_MMCR3), mfspr(SPRN_SIER2), mfspr(SPRN_SIER3));
}
#endif
pr_info("SIAR: %016lx SDAR: %016lx SIER: %016lx\n",
mfspr(SPRN_SIAR), sdar, sier);
local_irq_restore(flags);
}
/*
* Check if a set of events can all go on the PMU at once.
* If they can't, this will look at alternative codes for the events
* and see if any combination of alternative codes is feasible.
* The feasible set is returned in event_id[].
*/
static int power_check_constraints(struct cpu_hw_events *cpuhw,
u64 event_id[], unsigned int cflags[],
int n_ev)
{
unsigned long mask, value, nv;
unsigned long smasks[MAX_HWEVENTS], svalues[MAX_HWEVENTS];
int n_alt[MAX_HWEVENTS], choice[MAX_HWEVENTS];
int i, j;
unsigned long addf = ppmu->add_fields;
unsigned long tadd = ppmu->test_adder;
unsigned long grp_mask = ppmu->group_constraint_mask;
unsigned long grp_val = ppmu->group_constraint_val;
if (n_ev > ppmu->n_counter)
return -1;
/* First see if the events will go on as-is */
for (i = 0; i < n_ev; ++i) {
if ((cflags[i] & PPMU_LIMITED_PMC_REQD)
&& !ppmu->limited_pmc_event(event_id[i])) {
ppmu->get_alternatives(event_id[i], cflags[i],
cpuhw->alternatives[i]);
event_id[i] = cpuhw->alternatives[i][0];
}
if (ppmu->get_constraint(event_id[i], &cpuhw->amasks[i][0],
&cpuhw->avalues[i][0]))
return -1;
}
value = mask = 0;
for (i = 0; i < n_ev; ++i) {
nv = (value | cpuhw->avalues[i][0]) +
(value & cpuhw->avalues[i][0] & addf);
if (((((nv + tadd) ^ value) & mask) & (~grp_mask)) != 0)
break;
if (((((nv + tadd) ^ cpuhw->avalues[i][0]) & cpuhw->amasks[i][0])
& (~grp_mask)) != 0)
break;
value = nv;
mask |= cpuhw->amasks[i][0];
}
if (i == n_ev) {
if ((value & mask & grp_mask) != (mask & grp_val))
return -1;
else
return 0; /* all OK */
}
/* doesn't work, gather alternatives... */
if (!ppmu->get_alternatives)
return -1;
for (i = 0; i < n_ev; ++i) {
choice[i] = 0;
n_alt[i] = ppmu->get_alternatives(event_id[i], cflags[i],
cpuhw->alternatives[i]);
for (j = 1; j < n_alt[i]; ++j)
ppmu->get_constraint(cpuhw->alternatives[i][j],
&cpuhw->amasks[i][j],
&cpuhw->avalues[i][j]);
}
/* enumerate all possibilities and see if any will work */
i = 0;
j = -1;
value = mask = nv = 0;
while (i < n_ev) {
if (j >= 0) {
/* we're backtracking, restore context */
value = svalues[i];
mask = smasks[i];
j = choice[i];
}
/*
* See if any alternative k for event_id i,
* where k > j, will satisfy the constraints.
*/
while (++j < n_alt[i]) {
nv = (value | cpuhw->avalues[i][j]) +
(value & cpuhw->avalues[i][j] & addf);
if ((((nv + tadd) ^ value) & mask) == 0 &&
(((nv + tadd) ^ cpuhw->avalues[i][j])
& cpuhw->amasks[i][j]) == 0)
break;
}
if (j >= n_alt[i]) {
/*
* No feasible alternative, backtrack
* to event_id i-1 and continue enumerating its
* alternatives from where we got up to.
*/
if (--i < 0)
return -1;
} else {
/*
* Found a feasible alternative for event_id i,
* remember where we got up to with this event_id,
* go on to the next event_id, and start with
* the first alternative for it.
*/
choice[i] = j;
svalues[i] = value;
smasks[i] = mask;
value = nv;
mask |= cpuhw->amasks[i][j];
++i;
j = -1;
}
}
/* OK, we have a feasible combination, tell the caller the solution */
for (i = 0; i < n_ev; ++i)