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sched.h: always_inline alloc_tag_{save|restore} to fix modpost warnings

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Mark alloc_tag_{save|restore} as always_inline to fix the following
modpost warnings:

WARNING: modpost: vmlinux: section mismatch in reference: alloc_tag_save+0x1c (section: .text.unlikely) -> initcall_level_names (section: .init.data)
WARNING: modpost: vmlinux: section mismatch in reference: alloc_tag_restore+0x3c (section: .text.unlikely) -> initcall_level_names (section: .init.data)

The warnings happen when these functions are called from an __init
function and they don't get inlined (remain in the .text section) while
the value returned by get_current() points into .init.data section. 
Assuming get_current() always returns a valid address, this situation can
happen only during init stage and accessing .init.data from .text section
during that stage should pose no issues.

Link: https://lkml.kernel.org/r/20240704132506.1011978-1-surenb@google.com
Fixes: 22d407b164ff ("lib: add allocation tagging support for memory allocation profiling")
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202407032306.gi9nZsBi-lkp@intel.com/
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Suren Baghdasaryan 2024-07-04 06:25:05 -07:00 committed by Andrew Morton
parent 1e3d28fe03
commit 5a5aa3c376
1 changed files with 2 additions and 2 deletions
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4
include/linux/sched.h
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@ -2192,13 +2192,13 @@ static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
extern void sched_set_stop_task(int cpu, struct task_struct *stop);
#ifdef CONFIG_MEM_ALLOC_PROFILING
static inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag)
static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag)
{
swap(current->alloc_tag, tag);
return tag;
}
static inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old)
static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old)
{
#ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG
WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n");