* [PATCH] aarch64: Enable ifunc support.
@ 2013-11-26 11:14 Will Newton
2013-11-26 15:05 ` Marcus Shawcroft
` (3 more replies)
0 siblings, 4 replies; 9+ messages in thread
From: Will Newton @ 2013-11-26 11:14 UTC (permalink / raw)
To: libc-ports; +Cc: Patch Tracking
Add support for handling the R_AARCH64_IRELATIVE relocation and
STT_GNU_IFUNC symbols to the aarch64 port.
ports/ChangeLog.aarch64:
2013-11-25 Will Newton <will.newton@linaro.org>
* sysdeps/aarch64/dl-irel.h: Include ldsodefs.h.
(ELF_MACHINE_IRELA): Define. (elf_ifunc_invoke): Pass
hwcap to ifunc resolver function. (elf_irela): New function.
* sysdeps/aarch64/dl-machine.h: Include dl-irel.h.
(elf_machine_rela) Handle STT_GNU_IFUNC symbols and
R_AARCH64_IRELATIVE relocations. (elf_machine_lazy_rel):
Handle R_AARCH64_IRELATIVE relocations.
---
ports/sysdeps/aarch64/dl-irel.h | 22 +++++++++++++++++++---
ports/sysdeps/aarch64/dl-machine.h | 20 ++++++++++++++++++++
2 files changed, 39 insertions(+), 3 deletions(-)
diff --git a/ports/sysdeps/aarch64/dl-irel.h b/ports/sysdeps/aarch64/dl-irel.h
index 1a3811e..f37ee39 100644
--- a/ports/sysdeps/aarch64/dl-irel.h
+++ b/ports/sysdeps/aarch64/dl-irel.h
@@ -22,15 +22,31 @@
#include <stdio.h>
#include <unistd.h>
+#include <ldsodefs.h>
-/* AArch64 does not yet implement IFUNC support. However since
- 2011-06-20 provision of a elf_ifunc_invoke has been mandatory. */
+#define ELF_MACHINE_IRELA 1
static inline ElfW(Addr)
__attribute ((always_inline))
elf_ifunc_invoke (ElfW(Addr) addr)
{
- return ((ElfW(Addr) (*) (void)) (addr)) ();
+ return ((ElfW(Addr) (*) (unsigned long int)) (addr)) (GLRO(dl_hwcap));
+}
+
+static inline void
+__attribute ((always_inline))
+elf_irela (const ElfW(Rela) *reloc)
+{
+ ElfW(Addr) *const reloc_addr = (void *) reloc->r_offset;
+ const unsigned long int r_type = ELFW(R_TYPE) (reloc->r_info);
+
+ if (__glibc_likely (r_type == R_AARCH64_IRELATIVE))
+ {
+ ElfW(Addr) value = elf_ifunc_invoke (reloc->r_addend);
+ *reloc_addr = value;
+ }
+ else
+ __libc_fatal ("unexpected reloc type in static binary");
}
#endif
diff --git a/ports/sysdeps/aarch64/dl-machine.h b/ports/sysdeps/aarch64/dl-machine.h
index 71dd6b3..01a214f 100644
--- a/ports/sysdeps/aarch64/dl-machine.h
+++ b/ports/sysdeps/aarch64/dl-machine.h
@@ -23,6 +23,7 @@
#include <tls.h>
#include <dl-tlsdesc.h>
+#include <dl-irel.h>
/* Return nonzero iff ELF header is compatible with the running host. */
static inline int __attribute__ ((unused))
@@ -243,6 +244,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
ElfW(Addr) value = sym_map == NULL ? 0 : sym_map->l_addr + sym->st_value;
+ if (sym != NULL
+ && __glibc_unlikely (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC)
+ && __glibc_likely (sym->st_shndx != SHN_UNDEF)
+ && __glibc_likely (!skip_ifunc))
+ value = elf_ifunc_invoke (value);
+
switch (r_type)
{
case R_AARCH64_COPY:
@@ -331,6 +338,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
}
break;
+ case R_AARCH64_IRELATIVE:
+ value = map->l_addr + reloc->r_addend;
+ value = elf_ifunc_invoke (value);
+ *reloc_addr = value;
+ break;
+
default:
_dl_reloc_bad_type (map, r_type, 0);
break;
@@ -374,6 +387,13 @@ elf_machine_lazy_rel (struct link_map *map,
td->entry = (void*)(D_PTR (map, l_info[ADDRIDX (DT_TLSDESC_PLT)])
+ map->l_addr);
}
+ else if (__glibc_unlikely (r_type == R_AARCH64_IRELATIVE))
+ {
+ ElfW(Addr) value = map->l_addr + reloc->r_addend;
+ if (__glibc_likely (!skip_ifunc))
+ value = elf_ifunc_invoke (value);
+ *reloc_addr = value;
+ }
else
_dl_reloc_bad_type (map, r_type, 1);
}
--
1.8.1.4
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] aarch64: Enable ifunc support.
2013-11-26 11:14 [PATCH] aarch64: Enable ifunc support Will Newton
@ 2013-11-26 15:05 ` Marcus Shawcroft
2013-11-26 15:08 ` Will Newton
2013-11-26 15:17 ` Marcus Shawcroft
` (2 subsequent siblings)
3 siblings, 1 reply; 9+ messages in thread
From: Marcus Shawcroft @ 2013-11-26 15:05 UTC (permalink / raw)
To: Will Newton; +Cc: libc-ports, Patch Tracking
On 26 November 2013 08:57, Will Newton <will.newton@linaro.org> wrote:
> diff --git a/ports/sysdeps/aarch64/dl-irel.h b/ports/sysdeps/aarch64/dl-irel.h
> index 1a3811e..f37ee39 100644
> --- a/ports/sysdeps/aarch64/dl-irel.h
> +++ b/ports/sysdeps/aarch64/dl-irel.h
> @@ -22,15 +22,31 @@
>
> #include <stdio.h>
> #include <unistd.h>
> +#include <ldsodefs.h>
Will, is this include needed?
/Marcus
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] aarch64: Enable ifunc support.
2013-11-26 15:05 ` Marcus Shawcroft
@ 2013-11-26 15:08 ` Will Newton
0 siblings, 0 replies; 9+ messages in thread
From: Will Newton @ 2013-11-26 15:08 UTC (permalink / raw)
To: Marcus Shawcroft; +Cc: libc-ports, Patch Tracking
On 26 November 2013 14:51, Marcus Shawcroft <marcus.shawcroft@gmail.com> wrote:
> On 26 November 2013 08:57, Will Newton <will.newton@linaro.org> wrote:
>
>> diff --git a/ports/sysdeps/aarch64/dl-irel.h b/ports/sysdeps/aarch64/dl-irel.h
>> index 1a3811e..f37ee39 100644
>> --- a/ports/sysdeps/aarch64/dl-irel.h
>> +++ b/ports/sysdeps/aarch64/dl-irel.h
>> @@ -22,15 +22,31 @@
>>
>> #include <stdio.h>
>> #include <unistd.h>
>> +#include <ldsodefs.h>
>
> Will, is this include needed?
Yes, I believe it is needed for GLRO and ELFW, although everything
builds without it as ldsodefs.h is included all over the place.
stdio.h is required for __libc_fatal, not sure about unistd.h.
--
Will Newton
Toolchain Working Group, Linaro
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] aarch64: Enable ifunc support.
2013-11-26 11:14 [PATCH] aarch64: Enable ifunc support Will Newton
2013-11-26 15:05 ` Marcus Shawcroft
@ 2013-11-26 15:17 ` Marcus Shawcroft
2013-11-26 15:19 ` Carlos O'Donell
2013-11-26 15:41 ` Carlos O'Donell
3 siblings, 0 replies; 9+ messages in thread
From: Marcus Shawcroft @ 2013-11-26 15:17 UTC (permalink / raw)
To: Will Newton; +Cc: libc-ports, Patch Tracking
On 26 November 2013 08:57, Will Newton <will.newton@linaro.org> wrote:
>
> Add support for handling the R_AARCH64_IRELATIVE relocation and
> STT_GNU_IFUNC symbols to the aarch64 port.
>
> ports/ChangeLog.aarch64:
>
> 2013-11-25 Will Newton <will.newton@linaro.org>
>
> * sysdeps/aarch64/dl-irel.h: Include ldsodefs.h.
> (ELF_MACHINE_IRELA): Define. (elf_ifunc_invoke): Pass
> hwcap to ifunc resolver function. (elf_irela): New function.
> * sysdeps/aarch64/dl-machine.h: Include dl-irel.h.
> (elf_machine_rela) Handle STT_GNU_IFUNC symbols and
> R_AARCH64_IRELATIVE relocations. (elf_machine_lazy_rel):
> Handle R_AARCH64_IRELATIVE relocations.
OK /Marcus
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] aarch64: Enable ifunc support.
2013-11-26 11:14 [PATCH] aarch64: Enable ifunc support Will Newton
2013-11-26 15:05 ` Marcus Shawcroft
2013-11-26 15:17 ` Marcus Shawcroft
@ 2013-11-26 15:19 ` Carlos O'Donell
2013-11-26 15:24 ` Carlos O'Donell
2013-11-26 15:41 ` Carlos O'Donell
3 siblings, 1 reply; 9+ messages in thread
From: Carlos O'Donell @ 2013-11-26 15:19 UTC (permalink / raw)
To: Will Newton, libc-ports; +Cc: Patch Tracking
On 11/26/2013 03:57 AM, Will Newton wrote:
>
> Add support for handling the R_AARCH64_IRELATIVE relocation and
> STT_GNU_IFUNC symbols to the aarch64 port.
>
> ports/ChangeLog.aarch64:
>
> 2013-11-25 Will Newton <will.newton@linaro.org>
>
> * sysdeps/aarch64/dl-irel.h: Include ldsodefs.h.
> (ELF_MACHINE_IRELA): Define. (elf_ifunc_invoke): Pass
> hwcap to ifunc resolver function. (elf_irela): New function.
> * sysdeps/aarch64/dl-machine.h: Include dl-irel.h.
> (elf_machine_rela) Handle STT_GNU_IFUNC symbols and
> R_AARCH64_IRELATIVE relocations. (elf_machine_lazy_rel):
> Handle R_AARCH64_IRELATIVE relocations.
You don't appear to fix elf_ifunc_invoke to pass dl_hwcap to the
resolver which will need this to detect the different kinds of
hardware?
Please see the 32-bit ARM port.
Cheers,
Carlos.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] aarch64: Enable ifunc support.
2013-11-26 15:19 ` Carlos O'Donell
@ 2013-11-26 15:24 ` Carlos O'Donell
0 siblings, 0 replies; 9+ messages in thread
From: Carlos O'Donell @ 2013-11-26 15:24 UTC (permalink / raw)
To: Will Newton, libc-ports; +Cc: Patch Tracking
On 11/26/2013 10:16 AM, Carlos O'Donell wrote:
> On 11/26/2013 03:57 AM, Will Newton wrote:
>>
>> Add support for handling the R_AARCH64_IRELATIVE relocation and
>> STT_GNU_IFUNC symbols to the aarch64 port.
>>
>> ports/ChangeLog.aarch64:
>>
>> 2013-11-25 Will Newton <will.newton@linaro.org>
>>
>> * sysdeps/aarch64/dl-irel.h: Include ldsodefs.h.
>> (ELF_MACHINE_IRELA): Define. (elf_ifunc_invoke): Pass
>> hwcap to ifunc resolver function. (elf_irela): New function.
>> * sysdeps/aarch64/dl-machine.h: Include dl-irel.h.
>> (elf_machine_rela) Handle STT_GNU_IFUNC symbols and
>> R_AARCH64_IRELATIVE relocations. (elf_machine_lazy_rel):
>> Handle R_AARCH64_IRELATIVE relocations.
>
> You don't appear to fix elf_ifunc_invoke to pass dl_hwcap to the
> resolver which will need this to detect the different kinds of
> hardware?
Sorry, I'm wrong, I missed that line in your patch. You do pass
dl_hwcap.
c.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] aarch64: Enable ifunc support.
2013-11-26 11:14 [PATCH] aarch64: Enable ifunc support Will Newton
` (2 preceding siblings ...)
2013-11-26 15:19 ` Carlos O'Donell
@ 2013-11-26 15:41 ` Carlos O'Donell
2013-11-26 16:21 ` Will Newton
3 siblings, 1 reply; 9+ messages in thread
From: Carlos O'Donell @ 2013-11-26 15:41 UTC (permalink / raw)
To: Will Newton, libc-ports; +Cc: Patch Tracking
On 11/26/2013 03:57 AM, Will Newton wrote:
>
> Add support for handling the R_AARCH64_IRELATIVE relocation and
> STT_GNU_IFUNC symbols to the aarch64 port.
How did you test this?
> ports/ChangeLog.aarch64:
>
> 2013-11-25 Will Newton <will.newton@linaro.org>
>
> * sysdeps/aarch64/dl-irel.h: Include ldsodefs.h.
> (ELF_MACHINE_IRELA): Define. (elf_ifunc_invoke): Pass
> hwcap to ifunc resolver function. (elf_irela): New function.
> * sysdeps/aarch64/dl-machine.h: Include dl-irel.h.
> (elf_machine_rela) Handle STT_GNU_IFUNC symbols and
> R_AARCH64_IRELATIVE relocations. (elf_machine_lazy_rel):
> Handle R_AARCH64_IRELATIVE relocations.
> ---
> ports/sysdeps/aarch64/dl-irel.h | 22 +++++++++++++++++++---
> ports/sysdeps/aarch64/dl-machine.h | 20 ++++++++++++++++++++
> 2 files changed, 39 insertions(+), 3 deletions(-)
>
> diff --git a/ports/sysdeps/aarch64/dl-irel.h b/ports/sysdeps/aarch64/dl-irel.h
> index 1a3811e..f37ee39 100644
> --- a/ports/sysdeps/aarch64/dl-irel.h
> +++ b/ports/sysdeps/aarch64/dl-irel.h
> @@ -22,15 +22,31 @@
>
> #include <stdio.h>
> #include <unistd.h>
> +#include <ldsodefs.h>
>
> -/* AArch64 does not yet implement IFUNC support. However since
> - 2011-06-20 provision of a elf_ifunc_invoke has been mandatory. */
> +#define ELF_MACHINE_IRELA 1
OK.
>
> static inline ElfW(Addr)
> __attribute ((always_inline))
> elf_ifunc_invoke (ElfW(Addr) addr)
> {
> - return ((ElfW(Addr) (*) (void)) (addr)) ();
> + return ((ElfW(Addr) (*) (unsigned long int)) (addr)) (GLRO(dl_hwcap));
OK.
> +}
> +
> +static inline void
> +__attribute ((always_inline))
> +elf_irela (const ElfW(Rela) *reloc)
> +{
> + ElfW(Addr) *const reloc_addr = (void *) reloc->r_offset;
> + const unsigned long int r_type = ELFW(R_TYPE) (reloc->r_info);
> +
> + if (__glibc_likely (r_type == R_AARCH64_IRELATIVE))
> + {
> + ElfW(Addr) value = elf_ifunc_invoke (reloc->r_addend);
> + *reloc_addr = value;
> + }
> + else
> + __libc_fatal ("unexpected reloc type in static binary");
> }
OK.
>
> #endif
> diff --git a/ports/sysdeps/aarch64/dl-machine.h b/ports/sysdeps/aarch64/dl-machine.h
> index 71dd6b3..01a214f 100644
> --- a/ports/sysdeps/aarch64/dl-machine.h
> +++ b/ports/sysdeps/aarch64/dl-machine.h
> @@ -23,6 +23,7 @@
>
> #include <tls.h>
> #include <dl-tlsdesc.h>
> +#include <dl-irel.h>
>
> /* Return nonzero iff ELF header is compatible with the running host. */
> static inline int __attribute__ ((unused))
> @@ -243,6 +244,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
> struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
> ElfW(Addr) value = sym_map == NULL ? 0 : sym_map->l_addr + sym->st_value;
>
> + if (sym != NULL
> + && __glibc_unlikely (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC)
> + && __glibc_likely (sym->st_shndx != SHN_UNDEF)
> + && __glibc_likely (!skip_ifunc))
> + value = elf_ifunc_invoke (value);
OK.
> +
> switch (r_type)
> {
> case R_AARCH64_COPY:
> @@ -331,6 +338,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
> }
> break;
>
> + case R_AARCH64_IRELATIVE:
> + value = map->l_addr + reloc->r_addend;
> + value = elf_ifunc_invoke (value);
> + *reloc_addr = value;
> + break;
OK.
> +
> default:
> _dl_reloc_bad_type (map, r_type, 0);
> break;
> @@ -374,6 +387,13 @@ elf_machine_lazy_rel (struct link_map *map,
> td->entry = (void*)(D_PTR (map, l_info[ADDRIDX (DT_TLSDESC_PLT)])
> + map->l_addr);
> }
> + else if (__glibc_unlikely (r_type == R_AARCH64_IRELATIVE))
> + {
> + ElfW(Addr) value = map->l_addr + reloc->r_addend;
> + if (__glibc_likely (!skip_ifunc))
> + value = elf_ifunc_invoke (value);
> + *reloc_addr = value;
OK.
> + }
> else
> _dl_reloc_bad_type (map, r_type, 1);
> }
>
Looks good to me as long as your testing makes sense.
Cheers,
Carlos.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] aarch64: Enable ifunc support.
2013-11-26 15:41 ` Carlos O'Donell
@ 2013-11-26 16:21 ` Will Newton
2013-11-26 16:37 ` Carlos O'Donell
0 siblings, 1 reply; 9+ messages in thread
From: Will Newton @ 2013-11-26 16:21 UTC (permalink / raw)
To: Carlos O'Donell; +Cc: libc-ports, Patch Tracking
On 26 November 2013 15:24, Carlos O'Donell <carlos@redhat.com> wrote:
> On 11/26/2013 03:57 AM, Will Newton wrote:
>>
>> Add support for handling the R_AARCH64_IRELATIVE relocation and
>> STT_GNU_IFUNC symbols to the aarch64 port.
>
> How did you test this?
Running the glibc testsuite - which is actually a pretty good test for
the ifunc code. There's no functionality in the aarch64 port yet that
actually uses this yet so I couldn't test that. The only screw up that
the testsuite does not find is failing to pass hwcap correctly to the
resover, but I pretty intensively stared at that code and seen as
everything goes through elf_ifunc_invoke I am happy that it should
work in practice.
--
Will Newton
Toolchain Working Group, Linaro
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] aarch64: Enable ifunc support.
2013-11-26 16:21 ` Will Newton
@ 2013-11-26 16:37 ` Carlos O'Donell
0 siblings, 0 replies; 9+ messages in thread
From: Carlos O'Donell @ 2013-11-26 16:37 UTC (permalink / raw)
To: Will Newton; +Cc: libc-ports, Patch Tracking
On 11/26/2013 10:39 AM, Will Newton wrote:
> On 26 November 2013 15:24, Carlos O'Donell <carlos@redhat.com> wrote:
>> On 11/26/2013 03:57 AM, Will Newton wrote:
>>>
>>> Add support for handling the R_AARCH64_IRELATIVE relocation and
>>> STT_GNU_IFUNC symbols to the aarch64 port.
>>
>> How did you test this?
>
> Running the glibc testsuite - which is actually a pretty good test for
> the ifunc code. There's no functionality in the aarch64 port yet that
> actually uses this yet so I couldn't test that. The only screw up that
> the testsuite does not find is failing to pass hwcap correctly to the
> resover, but I pretty intensively stared at that code and seen as
> everything goes through elf_ifunc_invoke I am happy that it should
> work in practice.
Perfect, then I'm happy with the patch.
If Marcus is happy then I think you get to check this in.
Cheers,
Carlos.
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2013-11-26 16:25 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
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2013-11-26 11:14 [PATCH] aarch64: Enable ifunc support Will Newton
2013-11-26 15:05 ` Marcus Shawcroft
2013-11-26 15:08 ` Will Newton
2013-11-26 15:17 ` Marcus Shawcroft
2013-11-26 15:19 ` Carlos O'Donell
2013-11-26 15:24 ` Carlos O'Donell
2013-11-26 15:41 ` Carlos O'Donell
2013-11-26 16:21 ` Will Newton
2013-11-26 16:37 ` Carlos O'Donell
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