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Diffstat (limited to 'arch/x86/kernel/perf_regs.c')
-rw-r--r--arch/x86/kernel/perf_regs.c56
1 files changed, 41 insertions, 15 deletions
diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c
index 587d887f7f17..624703af80a1 100644
--- a/arch/x86/kernel/perf_regs.c
+++ b/arch/x86/kernel/perf_regs.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
@@ -58,18 +59,37 @@ static unsigned int pt_regs_offset[PERF_REG_X86_MAX] = {
u64 perf_reg_value(struct pt_regs *regs, int idx)
{
+ struct x86_perf_regs *perf_regs;
+
+ if (idx >= PERF_REG_X86_XMM0 && idx < PERF_REG_X86_XMM_MAX) {
+ perf_regs = container_of(regs, struct x86_perf_regs, regs);
+ if (!perf_regs->xmm_regs)
+ return 0;
+ return perf_regs->xmm_regs[idx - PERF_REG_X86_XMM0];
+ }
+
if (WARN_ON_ONCE(idx >= ARRAY_SIZE(pt_regs_offset)))
return 0;
return regs_get_register(regs, pt_regs_offset[idx]);
}
-#define REG_RESERVED (~((1ULL << PERF_REG_X86_MAX) - 1ULL))
+#define PERF_REG_X86_RESERVED (((1ULL << PERF_REG_X86_XMM0) - 1) & \
+ ~((1ULL << PERF_REG_X86_MAX) - 1))
#ifdef CONFIG_X86_32
+#define REG_NOSUPPORT ((1ULL << PERF_REG_X86_R8) | \
+ (1ULL << PERF_REG_X86_R9) | \
+ (1ULL << PERF_REG_X86_R10) | \
+ (1ULL << PERF_REG_X86_R11) | \
+ (1ULL << PERF_REG_X86_R12) | \
+ (1ULL << PERF_REG_X86_R13) | \
+ (1ULL << PERF_REG_X86_R14) | \
+ (1ULL << PERF_REG_X86_R15))
+
int perf_reg_validate(u64 mask)
{
- if (!mask || mask & REG_RESERVED)
+ if (!mask || (mask & (REG_NOSUPPORT | PERF_REG_X86_RESERVED)))
return -EINVAL;
return 0;
@@ -81,8 +101,7 @@ u64 perf_reg_abi(struct task_struct *task)
}
void perf_get_regs_user(struct perf_regs *regs_user,
- struct pt_regs *regs,
- struct pt_regs *regs_user_copy)
+ struct pt_regs *regs)
{
regs_user->regs = task_pt_regs(current);
regs_user->abi = perf_reg_abi(current);
@@ -95,10 +114,7 @@ void perf_get_regs_user(struct perf_regs *regs_user,
int perf_reg_validate(u64 mask)
{
- if (!mask || mask & REG_RESERVED)
- return -EINVAL;
-
- if (mask & REG_NOSUPPORT)
+ if (!mask || (mask & (REG_NOSUPPORT | PERF_REG_X86_RESERVED)))
return -EINVAL;
return 0;
@@ -106,18 +122,26 @@ int perf_reg_validate(u64 mask)
u64 perf_reg_abi(struct task_struct *task)
{
- if (test_tsk_thread_flag(task, TIF_IA32))
+ if (!user_64bit_mode(task_pt_regs(task)))
return PERF_SAMPLE_REGS_ABI_32;
else
return PERF_SAMPLE_REGS_ABI_64;
}
+static DEFINE_PER_CPU(struct pt_regs, nmi_user_regs);
+
void perf_get_regs_user(struct perf_regs *regs_user,
- struct pt_regs *regs,
- struct pt_regs *regs_user_copy)
+ struct pt_regs *regs)
{
+ struct pt_regs *regs_user_copy = this_cpu_ptr(&nmi_user_regs);
struct pt_regs *user_regs = task_pt_regs(current);
+ if (!in_nmi()) {
+ regs_user->regs = user_regs;
+ regs_user->abi = perf_reg_abi(current);
+ return;
+ }
+
/*
* If we're in an NMI that interrupted task_pt_regs setup, then
* we can't sample user regs at all. This check isn't really
@@ -150,17 +174,19 @@ void perf_get_regs_user(struct perf_regs *regs_user,
regs_user_copy->sp = user_regs->sp;
regs_user_copy->cs = user_regs->cs;
regs_user_copy->ss = user_regs->ss;
-
/*
- * Most system calls don't save these registers, don't report them.
+ * Store user space frame-pointer value on sample
+ * to facilitate stack unwinding for cases when
+ * user space executable code has such support
+ * enabled at compile time:
*/
+ regs_user_copy->bp = user_regs->bp;
+
regs_user_copy->bx = -1;
- regs_user_copy->bp = -1;
regs_user_copy->r12 = -1;
regs_user_copy->r13 = -1;
regs_user_copy->r14 = -1;
regs_user_copy->r15 = -1;
-
/*
* For this to be at all useful, we need a reasonable guess for
* the ABI. Be careful: we're in NMI context, and we're