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a0a4419e30
perf is failing to resolve symbols in the VDSO. A while (1) gettimeofday() loop shows: 93.99% [vdso] [.] 0x00000000000005e0 3.12% test [.] 00000037.plt_call.gettimeofday@@GLIBC_2.18 2.81% test [.] main The reason for this is that we are linking our VDSO shared libraries at 1MB, which is a little weird. Even though this is uncommon, Alan points out that it is valid and we should probably fix perf userspace. Regardless, I can't see a reason why we are doing this. The code is all position independent and we never rely on the VDSO ending up at 1M (and we never place it there on 64bit tasks). Changing our link address to 0x0 fixes perf VDSO symbol resolution: 73.18% [vdso] [.] 0x000000000000060c 12.39% [vdso] [.] __kernel_gettimeofday 3.58% test [.] 00000037.plt_call.gettimeofday@@GLIBC_2.18 2.94% [vdso] [.] __kernel_datapage_offset 2.90% test [.] main We still have some local symbol resolution issues that will be fixed in a subsequent patch. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
80 lines
1.5 KiB
C
80 lines
1.5 KiB
C
#ifndef __PPC64_VDSO_H__
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#define __PPC64_VDSO_H__
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#ifdef __KERNEL__
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/* Default link addresses for the vDSOs */
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#define VDSO32_LBASE 0x0
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#define VDSO64_LBASE 0x0
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/* Default map addresses for 32bit vDSO */
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#define VDSO32_MBASE 0x100000
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#define VDSO_VERSION_STRING LINUX_2.6.15
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/* Define if 64 bits VDSO has procedure descriptors */
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#undef VDS64_HAS_DESCRIPTORS
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#ifndef __ASSEMBLY__
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/* Offsets relative to thread->vdso_base */
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extern unsigned long vdso64_rt_sigtramp;
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extern unsigned long vdso32_sigtramp;
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extern unsigned long vdso32_rt_sigtramp;
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int vdso_getcpu_init(void);
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#else /* __ASSEMBLY__ */
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#ifdef __VDSO64__
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#ifdef VDS64_HAS_DESCRIPTORS
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#define V_FUNCTION_BEGIN(name) \
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.globl name; \
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.section ".opd","a"; \
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.align 3; \
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name: \
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.quad .name,.TOC.@tocbase,0; \
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.previous; \
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.globl .name; \
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.type .name,@function; \
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.name: \
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#define V_FUNCTION_END(name) \
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.size .name,.-.name;
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#define V_LOCAL_FUNC(name) (.name)
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#else /* VDS64_HAS_DESCRIPTORS */
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#define V_FUNCTION_BEGIN(name) \
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.globl name; \
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name: \
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#define V_FUNCTION_END(name) \
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.size name,.-name;
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#define V_LOCAL_FUNC(name) (name)
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#endif /* VDS64_HAS_DESCRIPTORS */
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#endif /* __VDSO64__ */
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#ifdef __VDSO32__
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#define V_FUNCTION_BEGIN(name) \
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.globl name; \
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.type name,@function; \
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name: \
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#define V_FUNCTION_END(name) \
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.size name,.-name;
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#define V_LOCAL_FUNC(name) (name)
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#endif /* __VDSO32__ */
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#endif /* __ASSEMBLY__ */
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#endif /* __KERNEL__ */
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#endif /* __PPC64_VDSO_H__ */
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