On 11/08/2016 02:57 AM, Michael Ellerman wrote:
Dmitry Safonov <0x7f454...@gmail.com> writes:
2016-10-27 20:09 GMT+03:00 Dmitry Safonov <dsafo...@virtuozzo.com>:
ping?
There's another series doing some similar changes:
http://www.spinics.net/lists/linux-mm/msg115860.html
Well, that version makes arch_mremap hook more general with renaming
vdso pointer. While this series erases that hook totaly.
So, we've agreed that it would be better without this hook, but with
generic version of vdso_mremap special_mapping helper:
https://marc.info/?i=d1aa8bec-a53e-cd30-e66a-39bebb6a4...@codeaurora.org
And I don't like all the macro games in 3/8, eg:
+#ifndef BITS
+#define BITS 32
+#endif
+
+#undef Elf_Ehdr
+#undef Elf_Sym
+#undef Elf_Shdr
+
+#define _CONCAT3(a, b, c) a ## b ## c
+#define CONCAT3(a, b, c) _CONCAT3(a, b, c)
+#define Elf_Ehdr CONCAT3(Elf, BITS, _Ehdr)
+#define Elf_Sym CONCAT3(Elf, BITS, _Sym)
+#define Elf_Shdr CONCAT3(Elf, BITS, _Shdr)
+#define VDSO_LBASE CONCAT3(VDSO, BITS, _LBASE)
+#define vdso_kbase CONCAT3(vdso, BITS, _kbase)
+#define vdso_pages CONCAT3(vdso, BITS, _pages)
+
+#undef pr_fmt
+#define pr_fmt(fmt) "vDSO" __stringify(BITS) ": " fmt
+
+#define lib_elfinfo CONCAT3(lib, BITS, _elfinfo)
+
+#define find_section CONCAT3(find_section, BITS,)
+static void * __init find_section(Elf_Ehdr *ehdr, const char *secname,
+ unsigned long *size)
I'd rather we kept the duplication of code than the obfuscation those
macros add.
If we can come up with a way to share more of the code without having to
do all those tricks then I'd be interested.
Well, ok, I thought it's quite common even outside of tracing:
e.g, fs/compat_binfmt_elf.c does quite the same trick.
But as you find it obscured - than ok, I will resend without that
common-vdso part.
cheers
--
Dmitry
