| Message ID | 73eda777eb55b19db402aad4ead96964cedd7550.1660573629.git.fweimer@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | Forced ordering for DFS ELF dependency sorting (bug 28937) | expand |
On 15/08/22 11:30, Florian Weimer via Libc-alpha wrote: > The new implementation will not be able to skip an arbitrary number > of objects. LGTM, thanks. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> > --- > elf/dl-sort-maps.c | 14 +++++++------- > sysdeps/generic/ldsodefs.h | 6 ++++-- > 2 files changed, 11 insertions(+), 9 deletions(-) > > diff --git a/elf/dl-sort-maps.c b/elf/dl-sort-maps.c > index 96638d7ed1..5b550b1e94 100644 > --- a/elf/dl-sort-maps.c > +++ b/elf/dl-sort-maps.c > @@ -27,12 +27,12 @@ > If FOR_FINI is true, this is called for finishing an object. */ > static void > _dl_sort_maps_original (struct link_map **maps, unsigned int nmaps, > - unsigned int skip, bool for_fini) > + bool force_first, bool for_fini) > { > /* Allows caller to do the common optimization of skipping the first map, > usually the main binary. */ > - maps += skip; > - nmaps -= skip; > + maps += force_first; > + nmaps -= force_first; > > /* A list of one element need not be sorted. */ > if (nmaps <= 1) > @@ -182,7 +182,7 @@ dfs_traversal (struct link_map ***rpo, struct link_map *map, > > static void > _dl_sort_maps_dfs (struct link_map **maps, unsigned int nmaps, > - unsigned int skip __attribute__ ((unused)), bool for_fini) > + bool force_first __attribute__ ((unused)), bool for_fini) > { > for (int i = nmaps - 1; i >= 0; i--) > maps[i]->l_visited = 0; > @@ -286,7 +286,7 @@ _dl_sort_maps_init (void) > > void > _dl_sort_maps (struct link_map **maps, unsigned int nmaps, > - unsigned int skip, bool for_fini) > + bool force_first, bool for_fini) > { > /* It can be tempting to use a static function pointer to store and call > the current selected sorting algorithm routine, but experimentation > @@ -296,9 +296,9 @@ _dl_sort_maps (struct link_map **maps, unsigned int nmaps, > input cases. A simple if-case with direct function calls appears to > be the fastest. */ > if (__glibc_likely (GLRO(dl_dso_sort_algo) == dso_sort_algorithm_original)) > - _dl_sort_maps_original (maps, nmaps, skip, for_fini); > + _dl_sort_maps_original (maps, nmaps, force_first, for_fini); > else > - _dl_sort_maps_dfs (maps, nmaps, skip, for_fini); > + _dl_sort_maps_dfs (maps, nmaps, force_first, for_fini); > } > > #endif /* HAVE_TUNABLES. */ > diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h > index 050a3032de..6b256b8388 100644 > --- a/sysdeps/generic/ldsodefs.h > +++ b/sysdeps/generic/ldsodefs.h > @@ -1048,9 +1048,11 @@ extern void _dl_init (struct link_map *main_map, int argc, char **argv, > initializer functions have completed. */ > extern void _dl_fini (void) attribute_hidden; > > -/* Sort array MAPS according to dependencies of the contained objects. */ > +/* Sort array MAPS according to dependencies of the contained objects. > + If FORCE_FIRST, MAPS[0] keeps its place even if the dependencies > + say otherwise. */ > extern void _dl_sort_maps (struct link_map **maps, unsigned int nmaps, > - unsigned int skip, bool for_fini) attribute_hidden; > + bool force_first, bool for_fini) attribute_hidden; > > /* The dynamic linker calls this function before and having changing > any shared object mappings. The `r_state' member of `struct r_debug'
diff --git a/elf/dl-sort-maps.c b/elf/dl-sort-maps.c index 96638d7ed1..5b550b1e94 100644 --- a/elf/dl-sort-maps.c +++ b/elf/dl-sort-maps.c @@ -27,12 +27,12 @@ If FOR_FINI is true, this is called for finishing an object. */ static void _dl_sort_maps_original (struct link_map **maps, unsigned int nmaps, - unsigned int skip, bool for_fini) + bool force_first, bool for_fini) { /* Allows caller to do the common optimization of skipping the first map, usually the main binary. */ - maps += skip; - nmaps -= skip; + maps += force_first; + nmaps -= force_first; /* A list of one element need not be sorted. */ if (nmaps <= 1) @@ -182,7 +182,7 @@ dfs_traversal (struct link_map ***rpo, struct link_map *map, static void _dl_sort_maps_dfs (struct link_map **maps, unsigned int nmaps, - unsigned int skip __attribute__ ((unused)), bool for_fini) + bool force_first __attribute__ ((unused)), bool for_fini) { for (int i = nmaps - 1; i >= 0; i--) maps[i]->l_visited = 0; @@ -286,7 +286,7 @@ _dl_sort_maps_init (void) void _dl_sort_maps (struct link_map **maps, unsigned int nmaps, - unsigned int skip, bool for_fini) + bool force_first, bool for_fini) { /* It can be tempting to use a static function pointer to store and call the current selected sorting algorithm routine, but experimentation @@ -296,9 +296,9 @@ _dl_sort_maps (struct link_map **maps, unsigned int nmaps, input cases. A simple if-case with direct function calls appears to be the fastest. */ if (__glibc_likely (GLRO(dl_dso_sort_algo) == dso_sort_algorithm_original)) - _dl_sort_maps_original (maps, nmaps, skip, for_fini); + _dl_sort_maps_original (maps, nmaps, force_first, for_fini); else - _dl_sort_maps_dfs (maps, nmaps, skip, for_fini); + _dl_sort_maps_dfs (maps, nmaps, force_first, for_fini); } #endif /* HAVE_TUNABLES. */ diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index 050a3032de..6b256b8388 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -1048,9 +1048,11 @@ extern void _dl_init (struct link_map *main_map, int argc, char **argv, initializer functions have completed. */ extern void _dl_fini (void) attribute_hidden; -/* Sort array MAPS according to dependencies of the contained objects. */ +/* Sort array MAPS according to dependencies of the contained objects. + If FORCE_FIRST, MAPS[0] keeps its place even if the dependencies + say otherwise. */ extern void _dl_sort_maps (struct link_map **maps, unsigned int nmaps, - unsigned int skip, bool for_fini) attribute_hidden; + bool force_first, bool for_fini) attribute_hidden; /* The dynamic linker calls this function before and having changing any shared object mappings. The `r_state' member of `struct r_debug'