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Re: [PATCH 2/2] powerpc: Move cache line size to rtld_global_ro
On 1/10/20 5:27 PM, Tulio Magno Quites Machado Filho wrote:
> Changes since v1:
> - Updated copyright dates
> - Added tests
> - Fixed coding style issues
> - Added macros __GLRO_DEF and __GLRO in the 64-bit case.
> - Removed sysdeps/unix/sysv/linux/powerpc/dl-support.c in favor of
> sysdeps/generic/dl-auxv.h which is included by elf/dl-support.c and
> elf/dl-sysdep.c
> - Removed sysdeps/unix/sysv/linux/powerpc/dl-sysdep.c
>
OK for master. This is probably the smallest change you can make to fix
all of this up.
This needs approval again by Siddhesh.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
> ----8<----
>
> GCC 10.0 enabled -fno-common by default and this started to point that
> __cache_line_size had been implemented in 2 different places: loader and
> libc.
>
> In order to avoid this duplication, the libc variable has been removed
> and the loader variable is moved to rtld_global_ro.
>
> File sysdeps/unix/sysv/linux/powerpc/dl-auxv.h has been added in order
> to reuse code for both static and dynamic linking scenarios.
> ---
> elf/dl-support.c | 3 +-
> elf/dl-sysdep.c | 3 +-
> sysdeps/generic/dl-auxv.h | 21 ++++++++
> sysdeps/powerpc/Makefile | 17 ++++++
> sysdeps/powerpc/dl-procinfo.c | 17 ++++++
> sysdeps/powerpc/mod-cache-ppc.c | 45 ++++++++++++++++
> sysdeps/powerpc/powerpc32/a2/memcpy.S | 23 ++++----
> sysdeps/powerpc/powerpc32/dl-machine.c | 11 ++--
> sysdeps/powerpc/powerpc32/memset.S | 29 +++++-----
> sysdeps/powerpc/powerpc32/sysdep.h | 26 +++++++++
> sysdeps/powerpc/powerpc64/a2/memcpy.S | 13 +++--
> sysdeps/powerpc/powerpc64/memset.S | 11 ++--
> sysdeps/powerpc/powerpc64/sysdep.h | 24 +++++++++
> sysdeps/powerpc/rtld-global-offsets.sym | 1 +
> sysdeps/powerpc/tst-cache-ppc-static-dlopen.c | 54 +++++++++++++++++++
> sysdeps/powerpc/tst-cache-ppc-static.c | 20 +++++++
> sysdeps/powerpc/tst-cache-ppc.c | 29 ++++++++++
> .../linux/powerpc/{dl-sysdep.c => dl-auxv.h} | 19 +++----
> sysdeps/unix/sysv/linux/powerpc/dl-static.c | 3 ++
> sysdeps/unix/sysv/linux/powerpc/libc-start.c | 10 ++--
> 20 files changed, 312 insertions(+), 67 deletions(-)
> create mode 100644 sysdeps/generic/dl-auxv.h
> create mode 100644 sysdeps/powerpc/mod-cache-ppc.c
> create mode 100644 sysdeps/powerpc/tst-cache-ppc-static-dlopen.c
> create mode 100644 sysdeps/powerpc/tst-cache-ppc-static.c
> create mode 100644 sysdeps/powerpc/tst-cache-ppc.c
> rename sysdeps/unix/sysv/linux/powerpc/{dl-sysdep.c => dl-auxv.h} (60%)
>
> diff --git a/elf/dl-support.c b/elf/dl-support.c
> index ad791ab6ab..7704c101c5 100644
> --- a/elf/dl-support.c
> +++ b/elf/dl-support.c
> @@ -36,6 +36,7 @@
> #include <stackinfo.h>
> #include <dl-vdso.h>
> #include <dl-vdso-setup.h>
> +#include <dl-auxv.h>
OK.
>
> extern char *__progname;
> char **_dl_argv = &__progname; /* This is checked for some error messages. */
> @@ -293,9 +294,7 @@ _dl_aux_init (ElfW(auxv_t) *av)
> case AT_RANDOM:
> _dl_random = (void *) av->a_un.a_val;
> break;
> -# ifdef DL_PLATFORM_AUXV
> DL_PLATFORM_AUXV
> -# endif
OK. Because DL_PLATFORM_AUXV is always defined now.
> }
> if (seen == 0xf)
> {
> diff --git a/elf/dl-sysdep.c b/elf/dl-sysdep.c
> index 53bbee14f4..854570821c 100644
> --- a/elf/dl-sysdep.c
> +++ b/elf/dl-sysdep.c
> @@ -45,6 +45,7 @@
> #include <tls.h>
>
> #include <dl-tunables.h>
> +#include <dl-auxv.h>
OK.
>
> extern char **_environ attribute_hidden;
> extern char _end[] attribute_hidden;
> @@ -180,9 +181,7 @@ _dl_sysdep_start (void **start_argptr,
> case AT_RANDOM:
> _dl_random = (void *) av->a_un.a_val;
> break;
> -#ifdef DL_PLATFORM_AUXV
> DL_PLATFORM_AUXV
> -#endif
OK. Because DL_PLATFORM_AUXV is always defined now.
> }
>
> #ifndef HAVE_AUX_SECURE
> diff --git a/sysdeps/generic/dl-auxv.h b/sysdeps/generic/dl-auxv.h
> new file mode 100644
> index 0000000000..bf3c01182e
> --- /dev/null
> +++ b/sysdeps/generic/dl-auxv.h
> @@ -0,0 +1,21 @@
> +/* Auxiliary vector processing. Generic version.
> + Copyright (C) 2020 Free Software Foundation, Inc.
OK.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <https://www.gnu.org/licenses/>. */
> +
> +/* Define DL_PLATFORM_AUXV in order to process platform-specific AUXV entries
> + during the initialization of the loader or of a static libc. */
> +#define DL_PLATFORM_AUXV
OK. Default version does nothing.
> diff --git a/sysdeps/powerpc/Makefile b/sysdeps/powerpc/Makefile
> index df45d348d2..d1c71a0ca4 100644
> --- a/sysdeps/powerpc/Makefile
> +++ b/sysdeps/powerpc/Makefile
> @@ -14,6 +14,23 @@ mod-tlsopt-powerpc.so-no-z-defs = yes
> tests += tst-tlsopt-powerpc
> $(objpfx)tst-tlsopt-powerpc: $(objpfx)mod-tlsopt-powerpc.so
>
> +tests-static += tst-cache-ppc-static
> +tests-internal += tst-cache-ppc-static
OK. Add one test.
> +
> +ifeq (yes,$(build-shared))
> +modules-names += mod-cache-ppc
> +tests += tst-cache-ppc tst-cache-ppc-static-dlopen
> +tests-static += tst-cache-ppc-static-dlopen
> +test-internal-extras += mod-cache-ppc
> +
> +mod-cache-ppc.so-no-z-defs = yes
> +tst-cache-ppc-static-dlopen-ENV = LD_LIBRARY_PATH=$(objpfx):$(common-objpfx):$(common-objpfx)elf
> +$(objpfx)tst-cache-ppc-static-dlopen: $(common-objpfx)dlfcn/libdl.a
> +$(objpfx)tst-cache-ppc-static-dlopen.out: $(objpfx)mod-cache-ppc.so
> +
> +$(objpfx)tst-cache-ppc: $(objpfx)mod-cache-ppc.so
> +endif
OK. Add two tests and modules.
> +
> ifneq (no,$(multi-arch))
> tests-static += tst-tlsifunc-static
> tests-internal += tst-tlsifunc-static
> diff --git a/sysdeps/powerpc/dl-procinfo.c b/sysdeps/powerpc/dl-procinfo.c
> index 2ae68c41f1..7a7d93dd0a 100644
> --- a/sysdeps/powerpc/dl-procinfo.c
> +++ b/sysdeps/powerpc/dl-procinfo.c
> @@ -89,5 +89,22 @@ PROCINFO_CLASS const char _dl_powerpc_cap_flags[64][15]
> ,
> #endif
>
> +#if !IS_IN (ldconfig)
> +# if !defined PROCINFO_DECL && defined SHARED
> + ._dl_cache_line_size
OK. Define cache line size.
> +# else
> +PROCINFO_CLASS int _dl_cache_line_size
> +# endif
> +# ifndef PROCINFO_DECL
> + = 0
> +# endif
> +# if !defined SHARED || defined PROCINFO_DECL
> +;
> +# else
> +,
> +# endif
> +#endif
> +
> +
> #undef PROCINFO_DECL
> #undef PROCINFO_CLASS
> diff --git a/sysdeps/powerpc/mod-cache-ppc.c b/sysdeps/powerpc/mod-cache-ppc.c
> new file mode 100644
> index 0000000000..81fad52078
> --- /dev/null
> +++ b/sysdeps/powerpc/mod-cache-ppc.c
> @@ -0,0 +1,45 @@
> +/* Test if an executable can read from rtld_global_ro._dl_cache_line_size.
> + Copyright (C) 2020 Free Software Foundation, Inc.
OK.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <https://www.gnu.org/licenses/>. */
> +
> +#include <stdio.h>
> +#include <stdint.h>
> +#include <inttypes.h>
> +#include <sys/auxv.h>
> +#include <ldsodefs.h>
> +#include <errno.h>
> +
> +/* errnop is required in order to work around BZ #20802. */
> +int
> +test_cache (int *errnop)
> +{
> + int cls1 = GLRO (dl_cache_line_size);
OK.
> + errno = *errnop;
> + uint64_t cls2 = getauxval (AT_DCACHEBSIZE);
OK.
> + *errnop = errno;
OK. Copy back errno.
> +
> + printf ("AT_DCACHEBSIZE = %" PRIu64 " B\n", cls2);
> + printf ("_dl_cache_line_size = %d B\n", cls1);
> +
> + if (cls1 != cls2)
> + {
> + printf ("error: _dl_cache_line_size != AT_DCACHEBSIZE\n");
> + return 1;
> + }
> +
> + return 0;
> +}
> diff --git a/sysdeps/powerpc/powerpc32/a2/memcpy.S b/sysdeps/powerpc/powerpc32/a2/memcpy.S
> index fe5dab847a..6f4d8a7b34 100644
> --- a/sysdeps/powerpc/powerpc32/a2/memcpy.S
> +++ b/sysdeps/powerpc/powerpc32/a2/memcpy.S
> @@ -18,6 +18,7 @@
> <https://www.gnu.org/licenses/>. */
>
> #include <sysdep.h>
> +#include <rtld-global-offsets.h>
OK.
>
> #define PREFETCH_AHEAD 4 /* no cache lines SRC prefetching ahead */
> #define ZERO_AHEAD 2 /* no cache lines DST zeroing ahead */
> @@ -106,25 +107,23 @@ EALIGN (memcpy, 5, 0)
> L(dst_aligned):
>
>
> -#ifdef SHARED
> +#ifdef PIC
> mflr r0
> -/* Establishes GOT addressability so we can load __cache_line_size
> - from static. This value was set from the aux vector during startup. */
> +/* Establishes GOT addressability so we can load the cache line size
> + from rtld_global_ro. This value was set from the aux vector during
> + startup. */
OK.
> SETUP_GOT_ACCESS(r9,got_label)
> - addis r9,r9,__cache_line_size-got_label@ha
> - lwz r9,__cache_line_size-got_label@l(r9)
> - mtlr r0
> -#else
> -/* Load __cache_line_size from static. This value was set from the
> - aux vector during startup. */
> - lis r9,__cache_line_size@ha
> - lwz r9,__cache_line_size@l(r9)
> + addis r9,r9,_GLOBAL_OFFSET_TABLE_-got_label@ha
> + addi r9,r9,_GLOBAL_OFFSET_TABLE_-got_label@l
> + mtlr r0
OK.
> #endif
> + __GLRO(r9, r9, _dl_cache_line_size,
> + RTLD_GLOBAL_RO_DL_CACHE_LINE_SIZE_OFFSET)
OK.
>
> cmplwi cr5, r9, 0
> bne+ cr5,L(cachelineset)
>
> -/* __cache_line_size not set: generic byte copy without much optimization */
> +/* Cache line size not set: generic byte copy without much optimization */
OK.
> andi. r0,r5,1 /* If length is odd copy one byte. */
> beq L(cachelinenotset_align)
> lbz r7,0(r4) /* Read one byte from source. */
> diff --git a/sysdeps/powerpc/powerpc32/dl-machine.c b/sysdeps/powerpc/powerpc32/dl-machine.c
> index d5ea4b97f4..6090e60d3c 100644
> --- a/sysdeps/powerpc/powerpc32/dl-machine.c
> +++ b/sysdeps/powerpc/powerpc32/dl-machine.c
> @@ -25,11 +25,6 @@
> #include <dl-machine.h>
> #include <_itoa.h>
>
> -/* The value __cache_line_size is defined in dl-sysdep.c and is initialised
> - by _dl_sysdep_start via DL_PLATFORM_INIT. */
> -extern int __cache_line_size attribute_hidden;
OK. Remove the use of __cache_line_size.
> -
> -
> /* Stuff for the PLT. */
> #define PLT_INITIAL_ENTRY_WORDS 18
> #define PLT_LONGBRANCH_ENTRY_WORDS 0
> @@ -309,14 +304,14 @@ __elf_machine_runtime_setup (struct link_map *map, int lazy, int profile)
>
> Assumes that dcbst and icbi apply to lines of 16 bytes or
> more. Current known line sizes are 16, 32, and 128 bytes.
> - The following gets the __cache_line_size, when available. */
> + The following gets the cache line size, when available. */
OK.
>
> /* Default minimum 4 words per cache line. */
> int line_size_words = 4;
>
> - if (lazy && __cache_line_size != 0)
> + if (lazy && GLRO(dl_cache_line_size) != 0)
OK.
> /* Convert bytes to words. */
> - line_size_words = __cache_line_size / 4;
> + line_size_words = GLRO(dl_cache_line_size) / 4;
OK.
>
> size_modified = lazy ? rel_offset_words : 6;
> for (i = 0; i < size_modified; i += line_size_words)
> diff --git a/sysdeps/powerpc/powerpc32/memset.S b/sysdeps/powerpc/powerpc32/memset.S
> index 5f614c07d7..26c37f8a17 100644
> --- a/sysdeps/powerpc/powerpc32/memset.S
> +++ b/sysdeps/powerpc/powerpc32/memset.S
> @@ -17,12 +17,13 @@
> <https://www.gnu.org/licenses/>. */
>
> #include <sysdep.h>
> +#include <rtld-global-offsets.h>
OK.
>
> /* void * [r3] memset (void *s [r3], int c [r4], size_t n [r5]));
> Returns 's'.
>
> The memset is done in four sizes: byte (8 bits), word (32 bits),
> - 32-byte blocks (256 bits) and __cache_line_size (128, 256, 1024 bits).
> + 32-byte blocks (256 bits) and cache line size (128, 256, 1024 bits).
OK.
> There is a special case for setting whole cache lines to 0, which
> takes advantage of the dcbz instruction. */
>
> @@ -95,7 +96,7 @@ L(caligned):
>
> /* Check if we can use the special case for clearing memory using dcbz.
> This requires that we know the correct cache line size for this
> - processor. Getting the __cache_line_size may require establishing GOT
> + processor. Getting the cache line size may require establishing GOT
OK.
> addressability, so branch out of line to set this up. */
> beq cr1, L(checklinesize)
>
> @@ -230,26 +231,22 @@ L(medium_28t):
> blr
>
> L(checklinesize):
> -#ifdef SHARED
> - mflr rTMP
> /* If the remaining length is less the 32 bytes then don't bother getting
> the cache line size. */
> beq L(medium)
> -/* Establishes GOT addressability so we can load __cache_line_size
> - from static. This value was set from the aux vector during startup. */
> +#ifdef PIC
> + mflr rTMP
> +/* Establishes GOT addressability so we can load the cache line size
> + from rtld_global_ro. This value was set from the aux vector during
> + startup. */
> SETUP_GOT_ACCESS(rGOT,got_label)
> - addis rGOT,rGOT,__cache_line_size-got_label@ha
> - lwz rCLS,__cache_line_size-got_label@l(rGOT)
> + addis rGOT,rGOT,_GLOBAL_OFFSET_TABLE_-got_label@ha
> + addi rGOT,rGOT,_GLOBAL_OFFSET_TABLE_-got_label@l
OK.
> mtlr rTMP
> -#else
> -/* Load __cache_line_size from static. This value was set from the
> - aux vector during startup. */
> - lis rCLS,__cache_line_size@ha
> -/* If the remaining length is less the 32 bytes then don't bother getting
> - the cache line size. */
> - beq L(medium)
> - lwz rCLS,__cache_line_size@l(rCLS)
> #endif
> +/* Load rtld_global_ro._dl_cache_line_size. */
> + __GLRO(rCLS, rGOT, _dl_cache_line_size,
> + RTLD_GLOBAL_RO_DL_CACHE_LINE_SIZE_OFFSET)
OK.
>
> /* If the cache line size was not set then goto to L(nondcbz), which is
> safe for any cache line size. */
> diff --git a/sysdeps/powerpc/powerpc32/sysdep.h b/sysdeps/powerpc/powerpc32/sysdep.h
> index ceed9ef158..0dee5f2757 100644
> --- a/sysdeps/powerpc/powerpc32/sysdep.h
> +++ b/sysdeps/powerpc/powerpc32/sysdep.h
> @@ -157,4 +157,30 @@ GOT_LABEL: ; \
> /* Label in text section. */
> #define C_TEXT(name) name
>
> +/* Read the value of member from rtld_global_ro. */
> +#ifdef PIC
> +# ifdef SHARED
> +# if IS_IN (rtld)
> +/* Inside ld.so we use the local alias to avoid runtime GOT
> + relocations. */
> +# define __GLRO(rOUT, rGOT, member, offset) \
> + lwz rOUT,_rtld_local_ro@got(rGOT); \
> + lwz rOUT,offset(rOUT)
OK. Within rtld use local.
> +# else
> +# define __GLRO(rOUT, rGOT, member, offset) \
> + lwz rOUT,_rtld_global_ro@got(rGOT); \
> + lwz rOUT,offset(rOUT)
OK.
> +# endif
> +# else
> +# define __GLRO(rOUT, rGOT, member, offset) \
> + lwz rOUT,member@got(rGOT); \
> + lwz rOUT,0(rOUT)
OK.
> +# endif
> +#else
> +/* Position-dependent code does not require access to the GOT. */
> +# define __GLRO(rOUT, rGOT, member, offset) \
> + lis rOUT,(member+LOWORD)@ha \
> + lwz rOUT,(member+LOWORD)@l(rOUT)
OK.
> +#endif /* PIC */
> +
> #endif /* __ASSEMBLER__ */
> diff --git a/sysdeps/powerpc/powerpc64/a2/memcpy.S b/sysdeps/powerpc/powerpc64/a2/memcpy.S
> index 0e3c435f3c..1162cc2207 100644
> --- a/sysdeps/powerpc/powerpc64/a2/memcpy.S
> +++ b/sysdeps/powerpc/powerpc64/a2/memcpy.S
> @@ -18,6 +18,7 @@
> <https://www.gnu.org/licenses/>. */
>
> #include <sysdep.h>
> +#include <rtld-global-offsets.h>
OK.
>
> #ifndef MEMCPY
> # define MEMCPY memcpy
> @@ -27,8 +28,9 @@
> #define ZERO_AHEAD 2 /* no cache lines DST zeroing ahead */
>
> .section ".toc","aw"
> -.LC0:
> - .tc __cache_line_size[TC],__cache_line_size
> +__GLRO_DEF(dl_cache_line_size)
> +
> +
OK.
> .section ".text"
> .align 2
>
> @@ -55,10 +57,11 @@ ENTRY (MEMCPY, 5)
> */
>
> neg r8,r3 /* LS 4 bits = # bytes to 8-byte dest bdry */
> - ld r9,.LC0@toc(r2) /* Get cache line size (part 1) */
> + /* Get the cache line size. */
> + __GLRO (r9, dl_cache_line_size,
> + RTLD_GLOBAL_RO_DL_CACHE_LINE_SIZE_OFFSET)
OK.
> clrldi r8,r8,64-4 /* align to 16byte boundary */
> sub r7,r4,r3 /* compute offset to src from dest */
> - lwz r9,0(r9) /* Get cache line size (part 2) */
> cmpldi cr0,r8,0 /* Were we aligned on a 16 byte bdy? */
> addi r10,r9,-1 /* Cache line mask */
> beq+ L(dst_aligned)
> @@ -121,7 +124,7 @@ L(dst_aligned):
> cmpdi cr0,r9,0 /* Cache line size set? */
> bne+ cr0,L(cachelineset)
>
> -/* __cache_line_size not set: generic byte copy without much optimization */
> +/* Cache line size not set: generic byte copy without much optimization */
OK.
> clrldi. r0,r5,63 /* If length is odd copy one byte */
> beq L(cachelinenotset_align)
> lbz r7,0(r4) /* Read one byte from source */
> diff --git a/sysdeps/powerpc/powerpc64/memset.S b/sysdeps/powerpc/powerpc64/memset.S
> index 857c023755..2fa98e6e2d 100644
> --- a/sysdeps/powerpc/powerpc64/memset.S
> +++ b/sysdeps/powerpc/powerpc64/memset.S
> @@ -17,10 +17,11 @@
> <https://www.gnu.org/licenses/>. */
>
> #include <sysdep.h>
> +#include <rtld-global-offsets.h>
OK.
>
> .section ".toc","aw"
> -.LC0:
> - .tc __cache_line_size[TC],__cache_line_size
> +__GLRO_DEF(dl_cache_line_size)
> +
OK.
> .section ".text"
> .align 2
>
> @@ -146,8 +147,10 @@ L(zloopstart):
> /* If the remaining length is less the 32 bytes, don't bother getting
> the cache line size. */
> beq L(medium)
> - ld rCLS,.LC0@toc(r2)
> - lwz rCLS,0(rCLS)
> + /* Read the cache line size. */
> + __GLRO (rCLS, dl_cache_line_size,
> + RTLD_GLOBAL_RO_DL_CACHE_LINE_SIZE_OFFSET)
> +
OK.
> /* If the cache line size was not set just goto to L(nondcbz) which is
> safe for any cache line size. */
> cmpldi cr1,rCLS,0
> diff --git a/sysdeps/powerpc/powerpc64/sysdep.h b/sysdeps/powerpc/powerpc64/sysdep.h
> index aefd29a14d..d6616ac905 100644
> --- a/sysdeps/powerpc/powerpc64/sysdep.h
> +++ b/sysdeps/powerpc/powerpc64/sysdep.h
> @@ -342,6 +342,30 @@ LT_LABELSUFFIX(name,_name_end): ; \
> #define PSEUDO_END_ERRVAL(name) \
> END (name)
>
> +#ifdef SHARED
> +# if IS_IN (rtld)
> + /* Inside ld.so we use the local alias to avoid runtime GOT
> + relocations. */
> +# define __GLRO_DEF(var) \
> +.LC__ ## var: \
> + .tc _rtld_local_ro[TC],_rtld_local_ro
OK.
> +# else
> +# define __GLRO_DEF(var) \
> +.LC__ ## var: \
> + .tc _rtld_global_ro[TC],_rtld_global_ro
> +# endif
> +# define __GLRO(rOUT, var, offset) \
> + ld rOUT,.LC__ ## var@toc(r2); \
> + lwz rOUT,offset(rOUT)
> +#else
> +# define __GLRO_DEF(var) \
> +.LC__ ## var: \
> + .tc _ ## var[TC],_ ## var
> +# define __GLRO(rOUT, var, offset) \
> + ld rOUT,.LC__ ## var@toc(r2); \
> + lwz rOUT,0(rOUT)
> +#endif
OK.
> +
> #else /* !__ASSEMBLER__ */
>
> #if _CALL_ELF != 2
> diff --git a/sysdeps/powerpc/rtld-global-offsets.sym b/sysdeps/powerpc/rtld-global-offsets.sym
> index f5ea5a1466..6b348fd522 100644
> --- a/sysdeps/powerpc/rtld-global-offsets.sym
> +++ b/sysdeps/powerpc/rtld-global-offsets.sym
> @@ -6,3 +6,4 @@
>
> RTLD_GLOBAL_RO_DL_HWCAP_OFFSET rtld_global_ro_offsetof (_dl_hwcap)
> RTLD_GLOBAL_RO_DL_HWCAP2_OFFSET rtld_global_ro_offsetof (_dl_hwcap2)
> +RTLD_GLOBAL_RO_DL_CACHE_LINE_SIZE_OFFSET rtld_global_ro_offsetof (_dl_cache_line_size)
Ok.
> diff --git a/sysdeps/powerpc/tst-cache-ppc-static-dlopen.c b/sysdeps/powerpc/tst-cache-ppc-static-dlopen.c
> new file mode 100644
> index 0000000000..296d0f4397
> --- /dev/null
> +++ b/sysdeps/powerpc/tst-cache-ppc-static-dlopen.c
> @@ -0,0 +1,54 @@
> +/* Test dl_cache_line_size from a dlopen'ed DSO from a static executable.
> + Copyright (C) 2020 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <https://www.gnu.org/licenses/>. */
> +
> +#include <dlfcn.h>
> +#include <stdio.h>
> +#include <errno.h>
> +
> +int test_cache(int *);
> +
> +static int
> +do_test (void)
> +{
> + int ret;
> + void *handle;
> + int (*test_cache) (int *);
> +
> + handle = dlopen ("mod-cache-ppc.so", RTLD_LAZY | RTLD_LOCAL);
> + if (handle == NULL)
> + {
> + printf ("dlopen (mod-cache-ppc.so): %s\n", dlerror ());
> + return 1;
> + }
> +
> + test_cache = dlsym (handle, "test_cache");
> + if (test_cache == NULL)
> + {
> + printf ("dlsym (test_cache): %s\n", dlerror ());
> + return 1;
> + }
> +
> + ret = test_cache(&errno);
> +
> + test_cache = NULL;
> + dlclose (handle);
OK.
> +
> + return ret;
> +}
> +
> +#include <support/test-driver.c>
> diff --git a/sysdeps/powerpc/tst-cache-ppc-static.c b/sysdeps/powerpc/tst-cache-ppc-static.c
> new file mode 100644
> index 0000000000..b0c417e822
> --- /dev/null
> +++ b/sysdeps/powerpc/tst-cache-ppc-static.c
> @@ -0,0 +1,20 @@
> +/* Test if an executable can read from _dl_cache_line_size.
> + Copyright (C) 2020 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <https://www.gnu.org/licenses/>. */
> +
> +#include "tst-cache-ppc.c"
> +#include "mod-cache-ppc.c"
OK.
> diff --git a/sysdeps/powerpc/tst-cache-ppc.c b/sysdeps/powerpc/tst-cache-ppc.c
> new file mode 100644
> index 0000000000..86c7117c43
> --- /dev/null
> +++ b/sysdeps/powerpc/tst-cache-ppc.c
> @@ -0,0 +1,29 @@
> +/* Test if an executable can read from rtld_global_ro._dl_cache_line_size.
> + Copyright (C) 2020 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <https://www.gnu.org/licenses/>. */
> +
> +#include <errno.h>
> +
> +int test_cache(int *);
> +
> +static int
> +do_test (void)
> +{
> + return test_cache(&errno);
> +}
OK.
> +
> +#include <support/test-driver.c>
> diff --git a/sysdeps/unix/sysv/linux/powerpc/dl-sysdep.c b/sysdeps/unix/sysv/linux/powerpc/dl-auxv.h
> similarity index 60%
> rename from sysdeps/unix/sysv/linux/powerpc/dl-sysdep.c
> rename to sysdeps/unix/sysv/linux/powerpc/dl-auxv.h
> index 5d65bc6303..be2189732a 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/dl-sysdep.c
> +++ b/sysdeps/unix/sysv/linux/powerpc/dl-auxv.h
> @@ -1,5 +1,5 @@
> -/* Operating system support for run-time dynamic linker. Linux/PPC version.
> - Copyright (C) 1997-2020 Free Software Foundation, Inc.
> +/* Auxiliary vector processing. Linux/PPC version.
> + Copyright (C) 2020 Free Software Foundation, Inc.
OK.
> This file is part of the GNU C Library.
>
> The GNU C Library is free software; you can redistribute it and/or
> @@ -16,18 +16,15 @@
> License along with the GNU C Library; if not, see
> <https://www.gnu.org/licenses/>. */
>
> -#include <config.h>
> #include <ldsodefs.h>
>
> -int __cache_line_size attribute_hidden;
> +#if IS_IN (libc) && !defined SHARED
> +int GLRO(dl_cache_line_size);
> +#endif
>
> -/* Scan the Aux Vector for the "Data Cache Block Size" entry. If found
> - verify that the static extern __cache_line_size is defined by checking
> - for not NULL. If it is defined then assign the cache block size
> - value to __cache_line_size. */
> +/* Scan the Aux Vector for the "Data Cache Block Size" entry and assign it
> + to dl_cache_line_size. */
> #define DL_PLATFORM_AUXV \
> case AT_DCACHEBSIZE: \
> - __cache_line_size = av->a_un.a_val; \
> + GLRO(dl_cache_line_size) = av->a_un.a_val; \
OK.
> break;
> -
> -#include <sysdeps/unix/sysv/linux/dl-sysdep.c>
> diff --git a/sysdeps/unix/sysv/linux/powerpc/dl-static.c b/sysdeps/unix/sysv/linux/powerpc/dl-static.c
> index 59ce4e8972..a77e07b503 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/dl-static.c
> +++ b/sysdeps/unix/sysv/linux/powerpc/dl-static.c
> @@ -30,12 +30,14 @@ _dl_var_init (void *array[])
> DL_AUXV = 1,
> DL_HWCAP = 2,
> DL_HWCAP2 = 3,
> + DL_CACHE_LINE_SIZE = 4
OK.
> };
>
> GLRO(dl_pagesize) = *((size_t *) array[DL_PAGESIZE]);
> GLRO(dl_auxv) = (ElfW(auxv_t) *) *((size_t *) array[DL_AUXV]);
> GLRO(dl_hwcap) = *((unsigned long int *) array[DL_HWCAP]);
> GLRO(dl_hwcap2) = *((unsigned long int *) array[DL_HWCAP2]);
> + GLRO(dl_cache_line_size) = (int) *((int *) array[DL_CACHE_LINE_SIZE]);
OK.
> }
>
> #else
> @@ -46,6 +48,7 @@ static void *variables[] =
> &GLRO(dl_auxv),
> &GLRO(dl_hwcap),
> &GLRO(dl_hwcap2),
> + &GLRO(dl_cache_line_size)
OK.
> };
>
> static void
> diff --git a/sysdeps/unix/sysv/linux/powerpc/libc-start.c b/sysdeps/unix/sysv/linux/powerpc/libc-start.c
> index 93f8659fa6..fc86d6e234 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/libc-start.c
> +++ b/sysdeps/unix/sysv/linux/powerpc/libc-start.c
> @@ -24,7 +24,6 @@
> #include <hwcapinfo.h>
> #endif
>
> -int __cache_line_size attribute_hidden;
OK.
> /* The main work is done in the generic function. */
> #define LIBC_START_MAIN generic_start_main
> #define LIBC_START_DISABLE_INLINE
> @@ -71,15 +70,12 @@ __libc_start_main (int argc, char **argv,
> rtld_fini = NULL;
> }
>
> - /* Initialize the __cache_line_size variable from the aux vector. For the
> - static case, we also need _dl_hwcap, _dl_hwcap2 and _dl_platform, so we
> - can call __tcb_parse_hwcap_and_convert_at_platform (). */
OK.
> for (ElfW (auxv_t) * av = auxvec; av->a_type != AT_NULL; ++av)
> switch (av->a_type)
> {
> - case AT_DCACHEBSIZE:
> - __cache_line_size = av->a_un.a_val;
> - break;
> + /* For the static case, we also need _dl_hwcap, _dl_hwcap2 and
> + _dl_platform, so we can call
> + __tcb_parse_hwcap_and_convert_at_platform (). */
OK.
> #ifndef SHARED
> case AT_HWCAP:
> _dl_hwcap = (unsigned long int) av->a_un.a_val;
>
--
Cheers,
Carlos.