[PATCH v4 14/39] perf/x86: Rename get_segment_base() and make it global

Josh Poimboeuf
2025-01-22T02:32:06Z

get_segment_base() will be used by the unwind_user code, so make it
global and rename it so it doesn't conflict with a KVM function of the
same name.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
arch/x86/events/core.c | 10 +++++-----
arch/x86/include/asm/perf_event.h | 2 ++
2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index c75c482d4c52..23ac6343cf86 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2790,7 +2790,7 @@ valid_user_frame(const void __user *fp, unsigned long size)
return __access_ok(fp, size);
}

-static unsigned long get_segment_base(unsigned int segment)
+unsigned long segment_base_address(unsigned int segment)
{
struct desc_struct *desc;
unsigned int idx = segment >> 3;
@@ -2874,8 +2874,8 @@ perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry_ctx *ent
if (user_64bit_mode(regs))
return 0;

- cs_base = get_segment_base(regs->cs);
- ss_base = get_segment_base(regs->ss);
+ cs_base = segment_base_address(regs->cs);
+ ss_base = segment_base_address(regs->ss);

fp = compat_ptr(ss_base + regs->bp);
pagefault_disable();
@@ -2994,11 +2994,11 @@ static unsigned long code_segment_base(struct pt_regs *regs)
return 0x10 * regs->cs;

if (user_mode(regs) && regs->cs != __USER_CS)
- return get_segment_base(regs->cs);
+ return segment_base_address(regs->cs);
#else
if (user_mode(regs) && !user_64bit_mode(regs) &&
regs->cs != __USER32_CS)
- return get_segment_base(regs->cs);
+ return segment_base_address(regs->cs);
#endif
return 0;
}
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index d95f902acc52..75956c68356f 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -639,4 +639,6 @@ static __always_inline void perf_lopwr_cb(bool lopwr_in)

#define arch_perf_out_copy_user copy_from_user_nmi

+unsigned long segment_base_address(unsigned int segment);
+
#endif /* _ASM_X86_PERF_EVENT_H */
--
2.48.1