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sh: Tidy up the dwarf module helpers.
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This enables us to build the dwarf unwinder both with modules enabled and
disabled in addition to reducing code size in the latter case. The
helpers are also consolidated, and modified to resemble the BUG module
helpers.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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Paul Mundt committed Oct 13, 2009
1 parent ac4fac8 commit 5a3abba
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Showing 3 changed files with 53 additions and 36 deletions.
11 changes: 9 additions & 2 deletions arch/sh/include/asm/dwarf.h
Original file line number Diff line number Diff line change
Expand Up @@ -198,6 +198,7 @@
#include <linux/compiler.h>
#include <linux/bug.h>
#include <linux/list.h>
#include <linux/module.h>

/*
* Read either the frame pointer (r14) or the stack pointer (r15).
Expand Down Expand Up @@ -382,8 +383,10 @@ static inline unsigned int DW_CFA_operand(unsigned long insn)
extern struct dwarf_frame *dwarf_unwind_stack(unsigned long,
struct dwarf_frame *);
extern void dwarf_free_frame(struct dwarf_frame *);
extern int dwarf_parse_section(char *, char *, struct module *);
extern void dwarf_module_unload(struct module *);

extern int module_dwarf_finalize(const Elf_Ehdr *, const Elf_Shdr *,
struct module *);
extern void module_dwarf_cleanup(struct module *);

#endif /* !__ASSEMBLY__ */

Expand Down Expand Up @@ -412,6 +415,10 @@ extern void dwarf_module_unload(struct module *);
static inline void dwarf_unwinder_init(void)
{
}

#define module_dwarf_finalize(hdr, sechdrs, me) (0)
#define module_dwarf_cleanup(mod) do { } while (0)

#endif

#endif /* CONFIG_DWARF_UNWINDER */
Expand Down
43 changes: 39 additions & 4 deletions arch/sh/kernel/dwarf.c
Original file line number Diff line number Diff line change
Expand Up @@ -20,6 +20,7 @@
#include <linux/list.h>
#include <linux/mempool.h>
#include <linux/mm.h>
#include <linux/elf.h>
#include <asm/dwarf.h>
#include <asm/unwinder.h>
#include <asm/sections.h>
Expand Down Expand Up @@ -895,8 +896,8 @@ static void dwarf_unwinder_cleanup(void)
*
* Parse the information in a .eh_frame section.
*/
int dwarf_parse_section(char *eh_frame_start, char *eh_frame_end,
struct module *mod)
static int dwarf_parse_section(char *eh_frame_start, char *eh_frame_end,
struct module *mod)
{
u32 entry_type;
void *p, *entry;
Expand Down Expand Up @@ -959,14 +960,47 @@ int dwarf_parse_section(char *eh_frame_start, char *eh_frame_end,
return err;
}

#ifdef CONFIG_MODULES
int module_dwarf_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
struct module *me)
{
unsigned int i, err;
unsigned long start, end;
char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;

start = end = 0;

for (i = 1; i < hdr->e_shnum; i++) {
/* Alloc bit cleared means "ignore it." */
if ((sechdrs[i].sh_flags & SHF_ALLOC)
&& !strcmp(secstrings+sechdrs[i].sh_name, ".eh_frame")) {
start = sechdrs[i].sh_addr;
end = start + sechdrs[i].sh_size;
break;
}
}

/* Did we find the .eh_frame section? */
if (i != hdr->e_shnum) {
err = dwarf_parse_section((char *)start, (char *)end, me);
if (err) {
printk(KERN_WARNING "%s: failed to parse DWARF info\n",
me->name);
return err;
}
}

return 0;
}

/**
* dwarf_module_unload - remove FDE/CIEs associated with @mod
* module_dwarf_cleanup - remove FDE/CIEs associated with @mod
* @mod: the module that is being unloaded
*
* Remove any FDEs and CIEs from the global lists that came from
* @mod's .eh_frame section because @mod is being unloaded.
*/
void dwarf_module_unload(struct module *mod)
void module_dwarf_cleanup(struct module *mod)
{
struct dwarf_fde *fde;
struct dwarf_cie *cie;
Expand Down Expand Up @@ -1004,6 +1038,7 @@ void dwarf_module_unload(struct module *mod)

spin_unlock_irqrestore(&dwarf_fde_lock, flags);
}
#endif /* CONFIG_MODULES */

/**
* dwarf_unwinder_init - initialise the dwarf unwinder
Expand Down
35 changes: 5 additions & 30 deletions arch/sh/kernel/module.c
Original file line number Diff line number Diff line change
Expand Up @@ -146,41 +146,16 @@ int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *me)
{
#ifdef CONFIG_DWARF_UNWINDER
unsigned int i, err;
unsigned long start, end;
char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;

start = end = 0;

for (i = 1; i < hdr->e_shnum; i++) {
/* Alloc bit cleared means "ignore it." */
if ((sechdrs[i].sh_flags & SHF_ALLOC)
&& !strcmp(secstrings+sechdrs[i].sh_name, ".eh_frame")) {
start = sechdrs[i].sh_addr;
end = start + sechdrs[i].sh_size;
break;
}
}
int ret = 0;

/* Did we find the .eh_frame section? */
if (i != hdr->e_shnum) {
err = dwarf_parse_section((char *)start, (char *)end, me);
if (err)
printk(KERN_WARNING "%s: failed to parse DWARF info\n",
me->name);
}

#endif /* CONFIG_DWARF_UNWINDER */
ret |= module_dwarf_finalize(hdr, sechdrs, me);
ret |= module_bug_finalize(hdr, sechdrs, me);

return module_bug_finalize(hdr, sechdrs, me);
return ret;
}

void module_arch_cleanup(struct module *mod)
{
module_bug_cleanup(mod);

#ifdef CONFIG_DWARF_UNWINDER
dwarf_module_unload(mod);
#endif /* CONFIG_DWARF_UNWINDER */
module_dwarf_cleanup(mod);
}

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