Files
linux/include/asm-generic/codetag.lds.h
Petr Pavlu d29d64afa2 codetag: avoid unused alloc_tags sections/symbols
With CONFIG_MEM_ALLOC_PROFILING=n, vmlinux and all modules unnecessarily
contain the symbols __start_alloc_tags and __stop_alloc_tags, which define
an empty range.  In the case of modules, the presence of these symbols
also forces the linker to create an empty .codetag.alloc_tags section.

Update codetag.lds.h to make the data conditional on
CONFIG_MEM_ALLOC_PROFILING.

Link: https://lkml.kernel.org/r/20250618125037.53182-1-petr.pavlu@suse.com
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Casey Chen <cachen@purestorage.com>
Cc: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09 22:42:14 -07:00

34 lines
935 B
C

/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef __ASM_GENERIC_CODETAG_LDS_H
#define __ASM_GENERIC_CODETAG_LDS_H
#ifdef CONFIG_MEM_ALLOC_PROFILING
#define IF_MEM_ALLOC_PROFILING(...) __VA_ARGS__
#else
#define IF_MEM_ALLOC_PROFILING(...)
#endif
#define SECTION_WITH_BOUNDARIES(_name) \
. = ALIGN(8); \
__start_##_name = .; \
KEEP(*(_name)) \
__stop_##_name = .;
#define CODETAG_SECTIONS() \
IF_MEM_ALLOC_PROFILING(SECTION_WITH_BOUNDARIES(alloc_tags))
#define MOD_SEPARATE_CODETAG_SECTION(_name) \
.codetag.##_name : { \
SECTION_WITH_BOUNDARIES(_name) \
}
/*
* For codetags which might be used after module unload, therefore might stay
* longer in memory. Each such codetag type has its own section so that we can
* unload them individually once unused.
*/
#define MOD_SEPARATE_CODETAG_SECTIONS() \
IF_MEM_ALLOC_PROFILING(MOD_SEPARATE_CODETAG_SECTION(alloc_tags))
#endif /* __ASM_GENERIC_CODETAG_LDS_H */