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Release 4.14 arch/x86/oprofile/op_model_amd.c

/*
 * @file op_model_amd.c
 * athlon / K7 / K8 / Family 10h model-specific MSR operations
 *
 * @remark Copyright 2002-2009 OProfile authors
 * @remark Read the file COPYING
 *
 * @author John Levon
 * @author Philippe Elie
 * @author Graydon Hoare
 * @author Robert Richter <robert.richter@amd.com>
 * @author Barry Kasindorf <barry.kasindorf@amd.com>
 * @author Jason Yeh <jason.yeh@amd.com>
 * @author Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
 */

#include <linux/oprofile.h>
#include <linux/device.h>
#include <linux/pci.h>
#include <linux/percpu.h>

#include <asm/ptrace.h>
#include <asm/msr.h>
#include <asm/nmi.h>
#include <asm/apic.h>
#include <asm/processor.h>

#include "op_x86_model.h"
#include "op_counter.h"

#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX

#define NUM_VIRT_COUNTERS	32
#else

#define NUM_VIRT_COUNTERS	0
#endif


#define OP_EVENT_MASK			0x0FFF

#define OP_CTR_OVERFLOW			(1ULL<<31)


#define MSR_AMD_EVENTSEL_RESERVED	((0xFFFFFCF0ULL<<32)|(1ULL<<21))


static int num_counters;

static unsigned long reset_value[OP_MAX_COUNTER];


#define IBS_FETCH_SIZE			6

#define IBS_OP_SIZE			12


static u32 ibs_caps;


struct ibs_config {
	
unsigned long op_enabled;
	
unsigned long fetch_enabled;
	
unsigned long max_cnt_fetch;
	
unsigned long max_cnt_op;
	
unsigned long rand_en;
	
unsigned long dispatched_ops;
	
unsigned long branch_target;
};


struct ibs_state {
	
u64		ibs_op_ctl;
	
int		branch_target;
	
unsigned long	sample_size;
};


static struct ibs_config ibs_config;

static struct ibs_state ibs_state;

/*
 * IBS randomization macros
 */

#define IBS_RANDOM_BITS			12

#define IBS_RANDOM_MASK			((1ULL << IBS_RANDOM_BITS) - 1)

#define IBS_RANDOM_MAXCNT_OFFSET	(1ULL << (IBS_RANDOM_BITS - 5))

/*
 * 16-bit Linear Feedback Shift Register (LFSR)
 *
 *                       16   14   13    11
 * Feedback polynomial = X  + X  + X  +  X  + 1
 */

static unsigned int lfsr_random(void) { static unsigned int lfsr_value = 0xF00D; unsigned int bit; /* Compute next bit to shift in */ bit = ((lfsr_value >> 0) ^ (lfsr_value >> 2) ^ (lfsr_value >> 3) ^ (lfsr_value >> 5)) & 0x0001; /* Advance to next register value */ lfsr_value = (lfsr_value >> 1) | (bit << 15); return lfsr_value; }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter6797.10%266.67%
John Levon22.90%133.33%
Total69100.00%3100.00%

/* * IBS software randomization * * The IBS periodic op counter is randomized in software. The lower 12 * bits of the 20 bit counter are randomized. IbsOpCurCnt is * initialized with a 12 bit random value. */
static inline u64 op_amd_randomize_ibs_op(u64 val) { unsigned int random = lfsr_random(); if (!(ibs_caps & IBS_CAPS_RDWROPCNT)) /* * Work around if the hw can not write to IbsOpCurCnt * * Randomize the lower 8 bits of the 16 bit * IbsOpMaxCnt [15:0] value in the range of -128 to * +127 by adding/subtracting an offset to the * maximum count (IbsOpMaxCnt). * * To avoid over or underflows and protect upper bits * starting at bit 16, the initial value for * IbsOpMaxCnt must fit in the range from 0x0081 to * 0xff80. */ val += (s8)(random >> 4); else val |= (u64)(random & IBS_RANDOM_MASK) << 32; return val; }

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PersonTokensPropCommitsCommitProp
Robert Richter55100.00%2100.00%
Total55100.00%2100.00%


static inline void op_amd_handle_ibs(struct pt_regs * const regs, struct op_msrs const * const msrs) { u64 val, ctl; struct op_entry entry; if (!ibs_caps) return; if (ibs_config.fetch_enabled) { rdmsrl(MSR_AMD64_IBSFETCHCTL, ctl); if (ctl & IBS_FETCH_VAL) { rdmsrl(MSR_AMD64_IBSFETCHLINAD, val); oprofile_write_reserve(&entry, regs, val, IBS_FETCH_CODE, IBS_FETCH_SIZE); oprofile_add_data64(&entry, val); oprofile_add_data64(&entry, ctl); rdmsrl(MSR_AMD64_IBSFETCHPHYSAD, val); oprofile_add_data64(&entry, val); oprofile_write_commit(&entry); /* reenable the IRQ */ ctl &= ~(IBS_FETCH_VAL | IBS_FETCH_CNT); ctl |= IBS_FETCH_ENABLE; wrmsrl(MSR_AMD64_IBSFETCHCTL, ctl); } } if (ibs_config.op_enabled) { rdmsrl(MSR_AMD64_IBSOPCTL, ctl); if (ctl & IBS_OP_VAL) { rdmsrl(MSR_AMD64_IBSOPRIP, val); oprofile_write_reserve(&entry, regs, val, IBS_OP_CODE, ibs_state.sample_size); oprofile_add_data64(&entry, val); rdmsrl(MSR_AMD64_IBSOPDATA, val); oprofile_add_data64(&entry, val); rdmsrl(MSR_AMD64_IBSOPDATA2, val); oprofile_add_data64(&entry, val); rdmsrl(MSR_AMD64_IBSOPDATA3, val); oprofile_add_data64(&entry, val); rdmsrl(MSR_AMD64_IBSDCLINAD, val); oprofile_add_data64(&entry, val); rdmsrl(MSR_AMD64_IBSDCPHYSAD, val); oprofile_add_data64(&entry, val); if (ibs_state.branch_target) { rdmsrl(MSR_AMD64_IBSBRTARGET, val); oprofile_add_data(&entry, (unsigned long)val); } oprofile_write_commit(&entry); /* reenable the IRQ */ ctl = op_amd_randomize_ibs_op(ibs_state.ibs_op_ctl); wrmsrl(MSR_AMD64_IBSOPCTL, ctl); } } }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter27587.03%1173.33%
Barry Kasindorf309.49%213.33%
John Levon92.85%16.67%
Suravee Suthikulpanit20.63%16.67%
Total316100.00%15100.00%


static inline void op_amd_start_ibs(void) { u64 val; if (!ibs_caps) return; memset(&ibs_state, 0, sizeof(ibs_state)); /* * Note: Since the max count settings may out of range we * write back the actual used values so that userland can read * it. */ if (ibs_config.fetch_enabled) { val = ibs_config.max_cnt_fetch >> 4; val = min(val, IBS_FETCH_MAX_CNT); ibs_config.max_cnt_fetch = val << 4; val |= ibs_config.rand_en ? IBS_FETCH_RAND_EN : 0; val |= IBS_FETCH_ENABLE; wrmsrl(MSR_AMD64_IBSFETCHCTL, val); } if (ibs_config.op_enabled) { val = ibs_config.max_cnt_op >> 4; if (!(ibs_caps & IBS_CAPS_RDWROPCNT)) { /* * IbsOpCurCnt not supported. See * op_amd_randomize_ibs_op() for details. */ val = clamp(val, 0x0081ULL, 0xFF80ULL); ibs_config.max_cnt_op = val << 4; } else { /* * The start value is randomized with a * positive offset, we need to compensate it * with the half of the randomized range. Also * avoid underflows. */ val += IBS_RANDOM_MAXCNT_OFFSET; if (ibs_caps & IBS_CAPS_OPCNTEXT) val = min(val, IBS_OP_MAX_CNT_EXT); else val = min(val, IBS_OP_MAX_CNT); ibs_config.max_cnt_op = (val - IBS_RANDOM_MAXCNT_OFFSET) << 4; } val = ((val & ~IBS_OP_MAX_CNT) << 4) | (val & IBS_OP_MAX_CNT); val |= ibs_config.dispatched_ops ? IBS_OP_CNT_CTL : 0; val |= IBS_OP_ENABLE; ibs_state.ibs_op_ctl = val; ibs_state.sample_size = IBS_OP_SIZE; if (ibs_config.branch_target) { ibs_state.branch_target = 1; ibs_state.sample_size++; } val = op_amd_randomize_ibs_op(ibs_state.ibs_op_ctl); wrmsrl(MSR_AMD64_IBSOPCTL, val); } }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter24996.51%685.71%
Barry Kasindorf93.49%114.29%
Total258100.00%7100.00%


static void op_amd_stop_ibs(void) { if (!ibs_caps) return; if (ibs_config.fetch_enabled) /* clear max count and enable */ wrmsrl(MSR_AMD64_IBSFETCHCTL, 0); if (ibs_config.op_enabled) /* clear max count and enable */ wrmsrl(MSR_AMD64_IBSOPCTL, 0); }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter2866.67%250.00%
Barry Kasindorf1023.81%125.00%
John Levon49.52%125.00%
Total42100.00%4100.00%

#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
static void op_mux_switch_ctrl(struct op_x86_model_spec const *model, struct op_msrs const * const msrs) { u64 val; int i; /* enable active counters */ for (i = 0; i < num_counters; ++i) { int virt = op_x86_phys_to_virt(i); if (!reset_value[virt]) continue; rdmsrl(msrs->controls[i].addr, val); val &= model->reserved; val |= op_x86_get_ctrl(model, &counter_config[virt]); wrmsrl(msrs->controls[i].addr, val); } }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter9590.48%466.67%
Barry Kasindorf65.71%116.67%
John Levon43.81%116.67%
Total105100.00%6100.00%

#endif /* functions for op_amd_spec */
static void op_amd_shutdown(struct op_msrs const * const msrs) { int i; for (i = 0; i < num_counters; ++i) { if (!msrs->counters[i].addr) continue; release_perfctr_nmi(MSR_K7_PERFCTR0 + i); release_evntsel_nmi(MSR_K7_EVNTSEL0 + i); } }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter5493.10%375.00%
Barry Kasindorf46.90%125.00%
Total58100.00%4100.00%


static int op_amd_fill_in_addresses(struct op_msrs * const msrs) { int i; for (i = 0; i < num_counters; i++) { if (!reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i)) goto fail; if (!reserve_evntsel_nmi(MSR_K7_EVNTSEL0 + i)) { release_perfctr_nmi(MSR_K7_PERFCTR0 + i); goto fail; } /* both registers must be reserved */ if (num_counters == AMD64_NUM_COUNTERS_CORE) { msrs->counters[i].addr = MSR_F15H_PERF_CTR + (i << 1); msrs->controls[i].addr = MSR_F15H_PERF_CTL + (i << 1); } else { msrs->controls[i].addr = MSR_K7_EVNTSEL0 + i; msrs->counters[i].addr = MSR_K7_PERFCTR0 + i; } continue; fail: if (!counter_config[i].enabled) continue; op_x86_warn_reserved(i); op_amd_shutdown(msrs); return -EBUSY; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter15894.05%675.00%
Barry Kasindorf74.17%112.50%
John Levon31.79%112.50%
Total168100.00%8100.00%


static void op_amd_setup_ctrs(struct op_x86_model_spec const *model, struct op_msrs const * const msrs) { u64 val; int i; /* setup reset_value */ for (i = 0; i < OP_MAX_COUNTER; ++i) { if (counter_config[i].enabled && msrs->counters[op_x86_virt_to_phys(i)].addr) reset_value[i] = counter_config[i].count; else reset_value[i] = 0; } /* clear all counters */ for (i = 0; i < num_counters; ++i) { if (!msrs->controls[i].addr) continue; rdmsrl(msrs->controls[i].addr, val); if (val & ARCH_PERFMON_EVENTSEL_ENABLE) op_x86_warn_in_use(i); val &= model->reserved; wrmsrl(msrs->controls[i].addr, val); /* * avoid a false detection of ctr overflows in NMI * handler */ wrmsrl(msrs->counters[i].addr, -1LL); } /* enable active counters */ for (i = 0; i < num_counters; ++i) { int virt = op_x86_phys_to_virt(i); if (!reset_value[virt]) continue; /* setup counter registers */ wrmsrl(msrs->counters[i].addr, -(u64)reset_value[virt]); /* setup control registers */ rdmsrl(msrs->controls[i].addr, val); val &= model->reserved; val |= op_x86_get_ctrl(model, &counter_config[virt]); wrmsrl(msrs->controls[i].addr, val); } }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter275100.00%6100.00%
Total275100.00%6100.00%


static int op_amd_check_ctrs(struct pt_regs * const regs, struct op_msrs const * const msrs) { u64 val; int i; for (i = 0; i < num_counters; ++i) { int virt = op_x86_phys_to_virt(i); if (!reset_value[virt]) continue; rdmsrl(msrs->counters[i].addr, val); /* bit is clear if overflowed: */ if (val & OP_CTR_OVERFLOW) continue; oprofile_add_sample(regs, virt); wrmsrl(msrs->counters[i].addr, -(u64)reset_value[virt]); } op_amd_handle_ibs(regs, msrs); /* See op_model_ppro.c */ return 1; }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter10891.53%872.73%
Jason Yeh54.24%19.09%
Barry Kasindorf43.39%19.09%
John Levon10.85%19.09%
Total118100.00%11100.00%


static void op_amd_start(struct op_msrs const * const msrs) { u64 val; int i; for (i = 0; i < num_counters; ++i) { if (!reset_value[op_x86_phys_to_virt(i)]) continue; rdmsrl(msrs->controls[i].addr, val); val |= ARCH_PERFMON_EVENTSEL_ENABLE; wrmsrl(msrs->controls[i].addr, val); } op_amd_start_ibs(); }

Contributors

PersonTokensPropCommitsCommitProp
John Levon3644.44%111.11%
Robert Richter3644.44%666.67%
Don Zickus67.41%111.11%
Barry Kasindorf33.70%111.11%
Total81100.00%9100.00%


static void op_amd_stop(struct op_msrs const * const msrs) { u64 val; int i; /* * Subtle: stop on all counters to avoid race with setting our * pm callback */ for (i = 0; i < num_counters; ++i) { if (!reset_value[op_x86_phys_to_virt(i)]) continue; rdmsrl(msrs->controls[i].addr, val); val &= ~ARCH_PERFMON_EVENTSEL_ENABLE; wrmsrl(msrs->controls[i].addr, val); } op_amd_stop_ibs(); }

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PersonTokensPropCommitsCommitProp
Barry Kasindorf4554.22%111.11%
Robert Richter3440.96%777.78%
Jason Yeh44.82%111.11%
Total83100.00%9100.00%

/* * check and reserve APIC extended interrupt LVT offset for IBS if * available */
static void init_ibs(void) { ibs_caps = get_ibs_caps(); if (!ibs_caps) return; printk(KERN_INFO "oprofile: AMD IBS detected (0x%08x)\n", ibs_caps); }

Contributors

PersonTokensPropCommitsCommitProp
Robert Richter2592.59%583.33%
Barry Kasindorf27.41%116.67%
Total27100.00%6100.00%

static int (*create_arch_files)(struct dentry *root);
static int setup_ibs_files(struct dentry *root) { struct dentry *dir; int ret = 0; /* architecture specific files */ if (create_arch_files) ret = create_arch_files(root); if (ret) return ret; if (!ibs_caps) return ret; /* model specific files */ /* setup some reasonable defaults */ memset(&ibs_config, 0, sizeof(ibs_config)); ibs_config.max_cnt_fetch = 250000; ibs_config.max_cnt_op = 250000; if (ibs_caps & IBS_CAPS_FETCHSAM) { dir = oprofilefs_mkdir(root, "ibs_fetch"); oprofilefs_create_ulong(dir, "enable", &ibs_config.fetch_enabled); oprofilefs_create_ulong(dir, "max_count", &ibs_config.max_cnt_fetch); oprofilefs_create_ulong(dir, "rand_enable", &ibs_config.rand_en); } if (ibs_caps & IBS_CAPS_OPSAM) { dir = oprofilefs_mkdir(root, "ibs_op"); oprofilefs_create_ulong(dir, "enable", &ibs_config.op_enabled); oprofilefs_create_ulong(dir, "max_count", &ibs_config.max_cnt_op); if (ibs_caps & IBS_CAPS_OPCNT) oprofilefs_create_ulong(dir, "dispatched_ops", &ibs_config.dispatched_ops); if (ibs_caps & IBS_CAPS_BRNTRGT) oprofilefs_create_ulong(dir, "branch_target", &ibs_config.branch_target); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Barry Kasindorf11253.85%111.11%
Robert Richter9445.19%777.78%
Al Viro20.96%111.11%
Total208100.00%9100.00%

struct op_x86_model_spec op_amd_spec;
static int op_amd_init(struct oprofile_operations *ops) { init_ibs(); create_arch_files = ops->create_files; ops->create_files = setup_ibs_files; if (boot_cpu_data.x86 == 0x15) { num_counters = AMD64_NUM_COUNTERS_CORE; } else { num_counters = AMD64_NUM_COUNTERS; } op_amd_spec.num_counters = num_counters; op_amd_spec.num_controls = num_counters; op_amd_spec.num_virt_counters = max(num_counters, NUM_VIRT_COUNTERS); return 0; }

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PersonTokensPropCommitsCommitProp
Robert Richter73100.00%6100.00%
Total73100.00%6100.00%

struct op_x86_model_spec op_amd_spec = { /* num_counters/num_controls filled in at runtime */ .reserved = MSR_AMD_EVENTSEL_RESERVED, .event_mask = OP_EVENT_MASK, .init = op_amd_init, .fill_in_addresses = &op_amd_fill_in_addresses, .setup_ctrs = &op_amd_setup_ctrs, .check_ctrs = &op_amd_check_ctrs, .start = &op_amd_start, .stop = &op_amd_stop, .shutdown = &op_amd_shutdown, #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX .switch_ctrl = &op_mux_switch_ctrl, #endif };

Overall Contributors

PersonTokensPropCommitsCommitProp
Robert Richter174479.71%4083.33%
Barry Kasindorf27612.61%24.17%
John Levon1105.03%12.08%
Jason Yeh401.83%12.08%
Don Zickus140.64%24.17%
Suravee Suthikulpanit20.09%12.08%
Al Viro20.09%12.08%
Total2188100.00%48100.00%
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