From: Peter Zijlstra <[email protected]> Avoid calling out to bsearch() by inlining it, for normal kernel configs this was the last external call and poke_int3_handler() is now fully self sufficient -- no calls to external code.
Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> --- arch/x86/kernel/alternative.c | 8 ++++---- arch/x86/kernel/traps.c | 5 +++++ 2 files changed, 9 insertions(+), 4 deletions(-) --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -979,7 +979,7 @@ static __always_inline void *text_poke_a return _stext + tp->rel_addr; } -static int noinstr patch_cmp(const void *key, const void *elt) +static __always_inline int patch_cmp(const void *key, const void *elt) { struct text_poke_loc *tp = (struct text_poke_loc *) elt; @@ -1023,9 +1023,9 @@ int noinstr poke_int3_handler(struct pt_ * Skip the binary search if there is a single member in the vector. */ if (unlikely(desc->nr_entries > 1)) { - tp = bsearch(ip, desc->vec, desc->nr_entries, - sizeof(struct text_poke_loc), - patch_cmp); + tp = __bsearch(ip, desc->vec, desc->nr_entries, + sizeof(struct text_poke_loc), + patch_cmp); if (!tp) goto out_put; } else { --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -566,6 +566,11 @@ DEFINE_IDTENTRY_ERRORCODE(exc_general_pr dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code) { + /* + * poke_int3_handler() is completely self contained code; it does (and + * must) *NOT* call out to anything, lest it hits upon yet another + * INT3. + */ if (poke_int3_handler(regs)) return;
