Yup.
And now that I'm looking at that call-chain (to see if it would make sense
to use some other more specific lock - doesn't look like it: all the
readers are using RCU and this is the only writer), I also give you this
trivial one-liner. It changes each_symbol() to not put that constant array
on the stack, resulting in changing
movq $C.388.31095, %rsi #, tmp85
subq $376, %rsp #,
movq %rdi, %rbx # fn, fn
leaq -208(%rbp), %rdi #, tmp84
movq %rbx, %rdx # fn,
rep movsl
xorl %esi, %esi #
leaq -208(%rbp), %rdi #, tmp87
movq %r12, %rcx # data,
call each_symbol_in_section.clone.0 #
into
xorl %esi, %esi #
subq $216, %rsp #,
movq %rdi, %rbx # fn, fn
movq $arr.31078, %rdi #,
call each_symbol_in_section.clone.0 #
which is not so much about being obviously shorter and simpler because we
don't unnecessarily copy that constant array around onto the stack, but
also about having a much smaller stack footprint (376 vs 216 bytes - see
the update of 'rsp').
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
Btw, feel free to consider all those peeling patches signed-off-on, since
they seem to work.
I don't think it's necessarily bad to have multiple exit targets (although
9 is pushing it), if the thing is short enough that you can fairly easily
see how they work. Not that it's quite there yet.
Linus
---
kernel/module.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/kernel/module.c b/kernel/module.c
index 01e8874..2602264 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -227,7 +227,7 @@ bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
unsigned int symnum, void *data), void *data)
{
struct module *mod;
- const struct symsearch arr[] = {
+ static const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
NOT_GPL_ONLY, false },
{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
--
