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authorLinus Torvalds2022-01-23 17:52:42 +0200
committerLinus Torvalds2022-01-23 17:52:42 +0200
commitdd81e1c7d5fb126e5fbc5c9e334d7b3ec29a16a0 (patch)
tree48e19d8200f89423353a692edf13cca1bb288aa6 /arch/powerpc
parentac5a9bb6b4fa22135b3e371ac9787de120e18c8d (diff)
parentaee101d7b95a03078945681dd7f7ea5e4a1e7686 (diff)
Merge tag 'powerpc-5.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman: - A series of bpf fixes, including an oops fix and some codegen fixes. - Fix a regression in syscall_get_arch() for compat processes. - Fix boot failure on some 32-bit systems with KASAN enabled. - A couple of other build/minor fixes. Thanks to Athira Rajeev, Christophe Leroy, Dmitry V. Levin, Jiri Olsa, Johan Almbladh, Maxime Bizon, Naveen N. Rao, and Nicholas Piggin. * tag 'powerpc-5.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64s: Mask SRR0 before checking against the masked NIP powerpc/perf: Only define power_pmu_wants_prompt_pmi() for CONFIG_PPC64 powerpc/32s: Fix kasan_init_region() for KASAN powerpc/time: Fix build failure due to do_hard_irq_enable() on PPC32 powerpc/audit: Fix syscall_get_arch() powerpc64/bpf: Limit 'ldbrx' to processors compliant with ISA v2.06 tools/bpf: Rename 'struct event' to avoid naming conflict powerpc/bpf: Update ldimm64 instructions during extra pass powerpc32/bpf: Fix codegen for bpf-to-bpf calls bpf: Guard against accessing NULL pt_regs in bpf_get_task_stack()
Diffstat (limited to 'arch/powerpc')
-rw-r--r--arch/powerpc/include/asm/book3s/32/mmu-hash.h2
-rw-r--r--arch/powerpc/include/asm/hw_irq.h2
-rw-r--r--arch/powerpc/include/asm/ppc-opcode.h1
-rw-r--r--arch/powerpc/include/asm/syscall.h4
-rw-r--r--arch/powerpc/include/asm/thread_info.h2
-rw-r--r--arch/powerpc/kernel/interrupt_64.S2
-rw-r--r--arch/powerpc/mm/book3s32/mmu.c10
-rw-r--r--arch/powerpc/mm/kasan/book3s_32.c59
-rw-r--r--arch/powerpc/net/bpf_jit_comp.c29
-rw-r--r--arch/powerpc/net/bpf_jit_comp32.c9
-rw-r--r--arch/powerpc/net/bpf_jit_comp64.c29
-rw-r--r--arch/powerpc/perf/core-book3s.c58
12 files changed, 125 insertions, 82 deletions
diff --git a/arch/powerpc/include/asm/book3s/32/mmu-hash.h b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
index 7be27862329f..78c6a5fde1d6 100644
--- a/arch/powerpc/include/asm/book3s/32/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
@@ -223,6 +223,8 @@ static __always_inline void update_user_segments(u32 val)
update_user_segment(15, val);
}
+int __init find_free_bat(void);
+unsigned int bat_block_size(unsigned long base, unsigned long top);
#endif /* !__ASSEMBLY__ */
/* We happily ignore the smaller BATs on 601, we don't actually use
diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h
index a58fb4aa6c81..674e5aaafcbd 100644
--- a/arch/powerpc/include/asm/hw_irq.h
+++ b/arch/powerpc/include/asm/hw_irq.h
@@ -473,7 +473,7 @@ static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
return !(regs->msr & MSR_EE);
}
-static inline bool should_hard_irq_enable(void)
+static __always_inline bool should_hard_irq_enable(void)
{
return false;
}
diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
index efad07081cc0..9675303b724e 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -500,6 +500,7 @@
#define PPC_RAW_LDX(r, base, b) (0x7c00002a | ___PPC_RT(r) | ___PPC_RA(base) | ___PPC_RB(b))
#define PPC_RAW_LHZ(r, base, i) (0xa0000000 | ___PPC_RT(r) | ___PPC_RA(base) | IMM_L(i))
#define PPC_RAW_LHBRX(r, base, b) (0x7c00062c | ___PPC_RT(r) | ___PPC_RA(base) | ___PPC_RB(b))
+#define PPC_RAW_LWBRX(r, base, b) (0x7c00042c | ___PPC_RT(r) | ___PPC_RA(base) | ___PPC_RB(b))
#define PPC_RAW_LDBRX(r, base, b) (0x7c000428 | ___PPC_RT(r) | ___PPC_RA(base) | ___PPC_RB(b))
#define PPC_RAW_STWCX(s, a, b) (0x7c00012d | ___PPC_RS(s) | ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_RAW_CMPWI(a, i) (0x2c000000 | ___PPC_RA(a) | IMM_L(i))
diff --git a/arch/powerpc/include/asm/syscall.h b/arch/powerpc/include/asm/syscall.h
index 52d05b465e3e..25fc8ad9a27a 100644
--- a/arch/powerpc/include/asm/syscall.h
+++ b/arch/powerpc/include/asm/syscall.h
@@ -90,7 +90,7 @@ static inline void syscall_get_arguments(struct task_struct *task,
unsigned long val, mask = -1UL;
unsigned int n = 6;
- if (is_32bit_task())
+ if (is_tsk_32bit_task(task))
mask = 0xffffffff;
while (n--) {
@@ -105,7 +105,7 @@ static inline void syscall_get_arguments(struct task_struct *task,
static inline int syscall_get_arch(struct task_struct *task)
{
- if (is_32bit_task())
+ if (is_tsk_32bit_task(task))
return AUDIT_ARCH_PPC;
else if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN))
return AUDIT_ARCH_PPC64LE;
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
index 5725029aaa29..d6e649b3c70b 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -168,8 +168,10 @@ static inline bool test_thread_local_flags(unsigned int flags)
#ifdef CONFIG_COMPAT
#define is_32bit_task() (test_thread_flag(TIF_32BIT))
+#define is_tsk_32bit_task(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT))
#else
#define is_32bit_task() (IS_ENABLED(CONFIG_PPC32))
+#define is_tsk_32bit_task(tsk) (IS_ENABLED(CONFIG_PPC32))
#endif
#if defined(CONFIG_PPC64)
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S
index 92088f848266..7bab2d7de372 100644
--- a/arch/powerpc/kernel/interrupt_64.S
+++ b/arch/powerpc/kernel/interrupt_64.S
@@ -30,6 +30,7 @@ COMPAT_SYS_CALL_TABLE:
.ifc \srr,srr
mfspr r11,SPRN_SRR0
ld r12,_NIP(r1)
+ clrrdi r11,r11,2
clrrdi r12,r12,2
100: tdne r11,r12
EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
@@ -40,6 +41,7 @@ COMPAT_SYS_CALL_TABLE:
.else
mfspr r11,SPRN_HSRR0
ld r12,_NIP(r1)
+ clrrdi r11,r11,2
clrrdi r12,r12,2
100: tdne r11,r12
EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c
index 94045b265b6b..203735caf691 100644
--- a/arch/powerpc/mm/book3s32/mmu.c
+++ b/arch/powerpc/mm/book3s32/mmu.c
@@ -76,7 +76,7 @@ unsigned long p_block_mapped(phys_addr_t pa)
return 0;
}
-static int __init find_free_bat(void)
+int __init find_free_bat(void)
{
int b;
int n = mmu_has_feature(MMU_FTR_USE_HIGH_BATS) ? 8 : 4;
@@ -100,7 +100,7 @@ static int __init find_free_bat(void)
* - block size has to be a power of two. This is calculated by finding the
* highest bit set to 1.
*/
-static unsigned int block_size(unsigned long base, unsigned long top)
+unsigned int bat_block_size(unsigned long base, unsigned long top)
{
unsigned int max_size = SZ_256M;
unsigned int base_shift = (ffs(base) - 1) & 31;
@@ -145,7 +145,7 @@ static unsigned long __init __mmu_mapin_ram(unsigned long base, unsigned long to
int idx;
while ((idx = find_free_bat()) != -1 && base != top) {
- unsigned int size = block_size(base, top);
+ unsigned int size = bat_block_size(base, top);
if (size < 128 << 10)
break;
@@ -201,12 +201,12 @@ void mmu_mark_initmem_nx(void)
unsigned long size;
for (i = 0; i < nb - 1 && base < top;) {
- size = block_size(base, top);
+ size = bat_block_size(base, top);
setibat(i++, PAGE_OFFSET + base, base, size, PAGE_KERNEL_TEXT);
base += size;
}
if (base < top) {
- size = block_size(base, top);
+ size = bat_block_size(base, top);
if ((top - base) > size) {
size <<= 1;
if (strict_kernel_rwx_enabled() && base + size > border)
diff --git a/arch/powerpc/mm/kasan/book3s_32.c b/arch/powerpc/mm/kasan/book3s_32.c
index 35b287b0a8da..450a67ef0bbe 100644
--- a/arch/powerpc/mm/kasan/book3s_32.c
+++ b/arch/powerpc/mm/kasan/book3s_32.c
@@ -10,48 +10,51 @@ int __init kasan_init_region(void *start, size_t size)
{
unsigned long k_start = (unsigned long)kasan_mem_to_shadow(start);
unsigned long k_end = (unsigned long)kasan_mem_to_shadow(start + size);
- unsigned long k_cur = k_start;
- int k_size = k_end - k_start;
- int k_size_base = 1 << (ffs(k_size) - 1);
+ unsigned long k_nobat = k_start;
+ unsigned long k_cur;
+ phys_addr_t phys;
int ret;
- void *block;
- block = memblock_alloc(k_size, k_size_base);
-
- if (block && k_size_base >= SZ_128K && k_start == ALIGN(k_start, k_size_base)) {
- int shift = ffs(k_size - k_size_base);
- int k_size_more = shift ? 1 << (shift - 1) : 0;
-
- setbat(-1, k_start, __pa(block), k_size_base, PAGE_KERNEL);
- if (k_size_more >= SZ_128K)
- setbat(-1, k_start + k_size_base, __pa(block) + k_size_base,
- k_size_more, PAGE_KERNEL);
- if (v_block_mapped(k_start))
- k_cur = k_start + k_size_base;
- if (v_block_mapped(k_start + k_size_base))
- k_cur = k_start + k_size_base + k_size_more;
-
- update_bats();
+ while (k_nobat < k_end) {
+ unsigned int k_size = bat_block_size(k_nobat, k_end);
+ int idx = find_free_bat();
+
+ if (idx == -1)
+ break;
+ if (k_size < SZ_128K)
+ break;
+ phys = memblock_phys_alloc_range(k_size, k_size, 0,
+ MEMBLOCK_ALLOC_ANYWHERE);
+ if (!phys)
+ break;
+
+ setbat(idx, k_nobat, phys, k_size, PAGE_KERNEL);
+ k_nobat += k_size;
}
+ if (k_nobat != k_start)
+ update_bats();
- if (!block)
- block = memblock_alloc(k_size, PAGE_SIZE);
- if (!block)
- return -ENOMEM;
+ if (k_nobat < k_end) {
+ phys = memblock_phys_alloc_range(k_end - k_nobat, PAGE_SIZE, 0,
+ MEMBLOCK_ALLOC_ANYWHERE);
+ if (!phys)
+ return -ENOMEM;
+ }
ret = kasan_init_shadow_page_tables(k_start, k_end);
if (ret)
return ret;
- kasan_update_early_region(k_start, k_cur, __pte(0));
+ kasan_update_early_region(k_start, k_nobat, __pte(0));
- for (; k_cur < k_end; k_cur += PAGE_SIZE) {
+ for (k_cur = k_nobat; k_cur < k_end; k_cur += PAGE_SIZE) {
pmd_t *pmd = pmd_off_k(k_cur);
- void *va = block + k_cur - k_start;
- pte_t pte = pfn_pte(PHYS_PFN(__pa(va)), PAGE_KERNEL);
+ pte_t pte = pfn_pte(PHYS_PFN(phys + k_cur - k_nobat), PAGE_KERNEL);
__set_pte_at(&init_mm, k_cur, pte_offset_kernel(pmd, k_cur), pte, 0);
}
flush_tlb_kernel_range(k_start, k_end);
+ memset(kasan_mem_to_shadow(start), 0, k_end - k_start);
+
return 0;
}
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index d6ffdd0f2309..56dd1f4e3e44 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -23,15 +23,15 @@ static void bpf_jit_fill_ill_insns(void *area, unsigned int size)
memset32(area, BREAKPOINT_INSTRUCTION, size / 4);
}
-/* Fix the branch target addresses for subprog calls */
-static int bpf_jit_fixup_subprog_calls(struct bpf_prog *fp, u32 *image,
- struct codegen_context *ctx, u32 *addrs)
+/* Fix updated addresses (for subprog calls, ldimm64, et al) during extra pass */
+static int bpf_jit_fixup_addresses(struct bpf_prog *fp, u32 *image,
+ struct codegen_context *ctx, u32 *addrs)
{
const struct bpf_insn *insn = fp->insnsi;
bool func_addr_fixed;
u64 func_addr;
u32 tmp_idx;
- int i, ret;
+ int i, j, ret;
for (i = 0; i < fp->len; i++) {
/*
@@ -66,6 +66,23 @@ static int bpf_jit_fixup_subprog_calls(struct bpf_prog *fp, u32 *image,
* of the JITed sequence remains unchanged.
*/
ctx->idx = tmp_idx;
+ } else if (insn[i].code == (BPF_LD | BPF_IMM | BPF_DW)) {
+ tmp_idx = ctx->idx;
+ ctx->idx = addrs[i] / 4;
+#ifdef CONFIG_PPC32
+ PPC_LI32(ctx->b2p[insn[i].dst_reg] - 1, (u32)insn[i + 1].imm);
+ PPC_LI32(ctx->b2p[insn[i].dst_reg], (u32)insn[i].imm);
+ for (j = ctx->idx - addrs[i] / 4; j < 4; j++)
+ EMIT(PPC_RAW_NOP());
+#else
+ func_addr = ((u64)(u32)insn[i].imm) | (((u64)(u32)insn[i + 1].imm) << 32);
+ PPC_LI64(b2p[insn[i].dst_reg], func_addr);
+ /* overwrite rest with nops */
+ for (j = ctx->idx - addrs[i] / 4; j < 5; j++)
+ EMIT(PPC_RAW_NOP());
+#endif
+ ctx->idx = tmp_idx;
+ i++;
}
}
@@ -200,13 +217,13 @@ skip_init_ctx:
/*
* Do not touch the prologue and epilogue as they will remain
* unchanged. Only fix the branch target address for subprog
- * calls in the body.
+ * calls in the body, and ldimm64 instructions.
*
* This does not change the offsets and lengths of the subprog
* call instruction sequences and hence, the size of the JITed
* image as well.
*/
- bpf_jit_fixup_subprog_calls(fp, code_base, &cgctx, addrs);
+ bpf_jit_fixup_addresses(fp, code_base, &cgctx, addrs);
/* There is no need to perform the usual passes. */
goto skip_codegen_passes;
diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c
index faaebd446cad..cf8dd8aea386 100644
--- a/arch/powerpc/net/bpf_jit_comp32.c
+++ b/arch/powerpc/net/bpf_jit_comp32.c
@@ -191,6 +191,9 @@ void bpf_jit_emit_func_call_rel(u32 *image, struct codegen_context *ctx, u64 fun
if (image && rel < 0x2000000 && rel >= -0x2000000) {
PPC_BL_ABS(func);
+ EMIT(PPC_RAW_NOP());
+ EMIT(PPC_RAW_NOP());
+ EMIT(PPC_RAW_NOP());
} else {
/* Load function address into r0 */
EMIT(PPC_RAW_LIS(_R0, IMM_H(func)));
@@ -290,6 +293,8 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
bool func_addr_fixed;
u64 func_addr;
u32 true_cond;
+ u32 tmp_idx;
+ int j;
/*
* addrs[] maps a BPF bytecode address into a real offset from
@@ -905,8 +910,12 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
* 16 byte instruction that uses two 'struct bpf_insn'
*/
case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */
+ tmp_idx = ctx->idx;
PPC_LI32(dst_reg_h, (u32)insn[i + 1].imm);
PPC_LI32(dst_reg, (u32)insn[i].imm);
+ /* padding to allow full 4 instructions for later patching */
+ for (j = ctx->idx - tmp_idx; j < 4; j++)
+ EMIT(PPC_RAW_NOP());
/* Adjust for two bpf instructions */
addrs[++i] = ctx->idx * 4;
break;
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index 9eae8d8ed340..e1e8c934308a 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -319,6 +319,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
u64 imm64;
u32 true_cond;
u32 tmp_idx;
+ int j;
/*
* addrs[] maps a BPF bytecode address into a real offset from
@@ -633,17 +634,21 @@ bpf_alu32_trunc:
EMIT(PPC_RAW_MR(dst_reg, b2p[TMP_REG_1]));
break;
case 64:
- /*
- * Way easier and faster(?) to store the value
- * into stack and then use ldbrx
- *
- * ctx->seen will be reliable in pass2, but
- * the instructions generated will remain the
- * same across all passes
- */
+ /* Store the value to stack and then use byte-reverse loads */
PPC_BPF_STL(dst_reg, 1, bpf_jit_stack_local(ctx));
EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], 1, bpf_jit_stack_local(ctx)));
- EMIT(PPC_RAW_LDBRX(dst_reg, 0, b2p[TMP_REG_1]));
+ if (cpu_has_feature(CPU_FTR_ARCH_206)) {
+ EMIT(PPC_RAW_LDBRX(dst_reg, 0, b2p[TMP_REG_1]));
+ } else {
+ EMIT(PPC_RAW_LWBRX(dst_reg, 0, b2p[TMP_REG_1]));
+ if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN))
+ EMIT(PPC_RAW_SLDI(dst_reg, dst_reg, 32));
+ EMIT(PPC_RAW_LI(b2p[TMP_REG_2], 4));
+ EMIT(PPC_RAW_LWBRX(b2p[TMP_REG_2], b2p[TMP_REG_2], b2p[TMP_REG_1]));
+ if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+ EMIT(PPC_RAW_SLDI(b2p[TMP_REG_2], b2p[TMP_REG_2], 32));
+ EMIT(PPC_RAW_OR(dst_reg, dst_reg, b2p[TMP_REG_2]));
+ }
break;
}
break;
@@ -848,9 +853,13 @@ emit_clear:
case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */
imm64 = ((u64)(u32) insn[i].imm) |
(((u64)(u32) insn[i+1].imm) << 32);
+ tmp_idx = ctx->idx;
+ PPC_LI64(dst_reg, imm64);
+ /* padding to allow full 5 instructions for later patching */
+ for (j = ctx->idx - tmp_idx; j < 5; j++)
+ EMIT(PPC_RAW_NOP());
/* Adjust for two bpf instructions */
addrs[++i] = ctx->idx * 4;
- PPC_LI64(dst_reg, imm64);
break;
/*
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index a684901b6965..32b98b7a1f86 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -776,6 +776,34 @@ static void pmao_restore_workaround(bool ebb)
mtspr(SPRN_PMC6, pmcs[5]);
}
+/*
+ * If the perf subsystem wants performance monitor interrupts as soon as
+ * possible (e.g., to sample the instruction address and stack chain),
+ * this should return true. The IRQ masking code can then enable MSR[EE]
+ * in some places (e.g., interrupt handlers) that allows PMI interrupts
+ * through to improve accuracy of profiles, at the cost of some performance.
+ *
+ * The PMU counters can be enabled by other means (e.g., sysfs raw SPR
+ * access), but in that case there is no need for prompt PMI handling.
+ *
+ * This currently returns true if any perf counter is being used. It
+ * could possibly return false if only events are being counted rather than
+ * samples being taken, but for now this is good enough.
+ */
+bool power_pmu_wants_prompt_pmi(void)
+{
+ struct cpu_hw_events *cpuhw;
+
+ /*
+ * This could simply test local_paca->pmcregs_in_use if that were not
+ * under ifdef KVM.
+ */
+ if (!ppmu)
+ return false;
+
+ cpuhw = this_cpu_ptr(&cpu_hw_events);
+ return cpuhw->n_events;
+}
#endif /* CONFIG_PPC64 */
static void perf_event_interrupt(struct pt_regs *regs);
@@ -2438,36 +2466,6 @@ static void perf_event_interrupt(struct pt_regs *regs)
perf_sample_event_took(sched_clock() - start_clock);
}
-/*
- * If the perf subsystem wants performance monitor interrupts as soon as
- * possible (e.g., to sample the instruction address and stack chain),
- * this should return true. The IRQ masking code can then enable MSR[EE]
- * in some places (e.g., interrupt handlers) that allows PMI interrupts
- * though to improve accuracy of profiles, at the cost of some performance.
- *
- * The PMU counters can be enabled by other means (e.g., sysfs raw SPR
- * access), but in that case there is no need for prompt PMI handling.
- *
- * This currently returns true if any perf counter is being used. It
- * could possibly return false if only events are being counted rather than
- * samples being taken, but for now this is good enough.
- */
-bool power_pmu_wants_prompt_pmi(void)
-{
- struct cpu_hw_events *cpuhw;
-
- /*
- * This could simply test local_paca->pmcregs_in_use if that were not
- * under ifdef KVM.
- */
-
- if (!ppmu)
- return false;
-
- cpuhw = this_cpu_ptr(&cpu_hw_events);
- return cpuhw->n_events;
-}
-
static int power_pmu_prepare_cpu(unsigned int cpu)
{
struct cpu_hw_events *cpuhw = &per_cpu(cpu_hw_events, cpu);