diff options
| author | Filippo Arcidiacono <filippo.arcidiacono@st.com> | 2010-08-02 17:23:35 +0200 |
|---|---|---|
| committer | Carmelo Amoroso <carmelo.amoroso@st.com> | 2010-09-17 16:13:17 +0200 |
| commit | a33796043bdef5345bc00a528c942f91a87af8e9 (patch) | |
| tree | d69b340439feac78601648c29efb34d9b889e5e8 /ldso/ldso/dl-startup.c | |
| parent | 02f56b3ae9f620528c3c1bb42662b4499d19f383 (diff) | |
ldso: Add runtime prelink support
Added runtime prelink support to be able to run a prelinked
application; at process startup only the conflicts will be relocated.
This speed up the startup time.
Signed-off-by: Filippo Arcidiacono <filippo.arcidiacono@st.com>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
Diffstat (limited to 'ldso/ldso/dl-startup.c')
| -rw-r--r-- | ldso/ldso/dl-startup.c | 33 |
1 files changed, 29 insertions, 4 deletions
diff --git a/ldso/ldso/dl-startup.c b/ldso/ldso/dl-startup.c index feffa787b..4799846ee 100644 --- a/ldso/ldso/dl-startup.c +++ b/ldso/ldso/dl-startup.c @@ -94,6 +94,11 @@ /* Pull in all the arch specific stuff */ #include "dl-startup.h" +#ifdef __LDSO_PRELINK_SUPPORT__ +/* These defined magically in the linker script. */ +extern char _begin[] attribute_hidden; +#endif + /* Static declarations */ static int (*_dl_elf_main) (int, char **, char **); @@ -164,11 +169,26 @@ DL_START(unsigned long args) aux_dat += 2; } - /* locate the ELF header. We need this done as soon as possible - * (esp since SEND_STDERR() needs this on some platforms... */ + /* + * Locate the dynamic linker ELF header. We need this done as soon as + * possible (esp since SEND_STDERR() needs this on some platforms... + */ + +#ifdef __LDSO_PRELINK_SUPPORT__ + /* + * The `_begin' symbol created by the linker script points to ld.so ELF + * We use it if the kernel is not passing a valid address through the auxvt. + */ + + if (!auxvt[AT_BASE].a_un.a_val) + auxvt[AT_BASE].a_un.a_val = (Elf32_Addr) &_begin; + /* Note: if the dynamic linker itself is prelinked, the load_addr is 0 */ + DL_INIT_LOADADDR_BOOT(load_addr, elf_machine_load_address()); +#else if (!auxvt[AT_BASE].a_un.a_val) auxvt[AT_BASE].a_un.a_val = elf_machine_load_address(); DL_INIT_LOADADDR_BOOT(load_addr, auxvt[AT_BASE].a_un.a_val); +#endif header = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val; /* Check the ELF header to make sure everything looks ok. */ @@ -183,7 +203,7 @@ DL_START(unsigned long args) _dl_exit(0); } SEND_EARLY_STDERR_DEBUG("ELF header="); - SEND_ADDRESS_STDERR_DEBUG(DL_LOADADDR_BASE(load_addr), 1); + SEND_ADDRESS_STDERR_DEBUG(DL_LOADADDR_BASE(header), 1); /* Locate the global offset table. Since this code must be PIC * we can take advantage of the magic offset register, if we @@ -258,7 +278,12 @@ DL_START(unsigned long args) if (!indx && relative_count) { rel_size -= relative_count * sizeof(ELF_RELOC); - elf_machine_relative(load_addr, rel_addr, relative_count); + if (load_addr +#ifdef __LDSO_PRELINK_SUPPORT__ + || !tpnt->dynamic_info[DT_GNU_PRELINKED_IDX] +#endif + ) + elf_machine_relative(load_addr, rel_addr, relative_count); rel_addr += relative_count * sizeof(ELF_RELOC); } |