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author | Ilya Leoshkevich <iii@linux.ibm.com> | 2024-03-21 01:47:49 +0300 |
---|---|---|
committer | Vasily Gorbik <gor@linux.ibm.com> | 2024-04-03 16:00:20 +0300 |
commit | c9c260681f521e4ad9f9f4cc71fe35b978e06222 (patch) | |
tree | a9a4ff0b4395d595204870a6856586b1daa2c7b3 /arch/s390 | |
parent | 01cac82ae02b43983173ea8e475a1c999edd25a6 (diff) | |
download | linux-c9c260681f521e4ad9f9f4cc71fe35b978e06222.tar.xz |
s390/preempt: mark all functions __always_inline
preempt_count-related functions are quite ubiquitous and may be called
by noinstr ones, introducing unwanted instrumentation. Here is one
example call chain:
irqentry_nmi_enter() # noinstr
lockdep_hardirqs_enabled()
this_cpu_read()
__pcpu_size_call_return()
this_cpu_read_*()
this_cpu_generic_read()
__this_cpu_generic_read_nopreempt()
preempt_disable_notrace()
__preempt_count_inc()
__preempt_count_add()
They are very small, so there are no significant downsides to
force-inlining them.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20240320230007.4782-3-iii@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch/s390')
-rw-r--r-- | arch/s390/include/asm/preempt.h | 36 |
1 files changed, 18 insertions, 18 deletions
diff --git a/arch/s390/include/asm/preempt.h b/arch/s390/include/asm/preempt.h index bf15da0fedbc..0e3da500e98c 100644 --- a/arch/s390/include/asm/preempt.h +++ b/arch/s390/include/asm/preempt.h @@ -12,12 +12,12 @@ #define PREEMPT_NEED_RESCHED 0x80000000 #define PREEMPT_ENABLED (0 + PREEMPT_NEED_RESCHED) -static inline int preempt_count(void) +static __always_inline int preempt_count(void) { return READ_ONCE(S390_lowcore.preempt_count) & ~PREEMPT_NEED_RESCHED; } -static inline void preempt_count_set(int pc) +static __always_inline void preempt_count_set(int pc) { int old, new; @@ -29,22 +29,22 @@ static inline void preempt_count_set(int pc) old, new) != old); } -static inline void set_preempt_need_resched(void) +static __always_inline void set_preempt_need_resched(void) { __atomic_and(~PREEMPT_NEED_RESCHED, &S390_lowcore.preempt_count); } -static inline void clear_preempt_need_resched(void) +static __always_inline void clear_preempt_need_resched(void) { __atomic_or(PREEMPT_NEED_RESCHED, &S390_lowcore.preempt_count); } -static inline bool test_preempt_need_resched(void) +static __always_inline bool test_preempt_need_resched(void) { return !(READ_ONCE(S390_lowcore.preempt_count) & PREEMPT_NEED_RESCHED); } -static inline void __preempt_count_add(int val) +static __always_inline void __preempt_count_add(int val) { /* * With some obscure config options and CONFIG_PROFILE_ALL_BRANCHES @@ -59,17 +59,17 @@ static inline void __preempt_count_add(int val) __atomic_add(val, &S390_lowcore.preempt_count); } -static inline void __preempt_count_sub(int val) +static __always_inline void __preempt_count_sub(int val) { __preempt_count_add(-val); } -static inline bool __preempt_count_dec_and_test(void) +static __always_inline bool __preempt_count_dec_and_test(void) { return __atomic_add(-1, &S390_lowcore.preempt_count) == 1; } -static inline bool should_resched(int preempt_offset) +static __always_inline bool should_resched(int preempt_offset) { return unlikely(READ_ONCE(S390_lowcore.preempt_count) == preempt_offset); @@ -79,45 +79,45 @@ static inline bool should_resched(int preempt_offset) #define PREEMPT_ENABLED (0) -static inline int preempt_count(void) +static __always_inline int preempt_count(void) { return READ_ONCE(S390_lowcore.preempt_count); } -static inline void preempt_count_set(int pc) +static __always_inline void preempt_count_set(int pc) { S390_lowcore.preempt_count = pc; } -static inline void set_preempt_need_resched(void) +static __always_inline void set_preempt_need_resched(void) { } -static inline void clear_preempt_need_resched(void) +static __always_inline void clear_preempt_need_resched(void) { } -static inline bool test_preempt_need_resched(void) +static __always_inline bool test_preempt_need_resched(void) { return false; } -static inline void __preempt_count_add(int val) +static __always_inline void __preempt_count_add(int val) { S390_lowcore.preempt_count += val; } -static inline void __preempt_count_sub(int val) +static __always_inline void __preempt_count_sub(int val) { S390_lowcore.preempt_count -= val; } -static inline bool __preempt_count_dec_and_test(void) +static __always_inline bool __preempt_count_dec_and_test(void) { return !--S390_lowcore.preempt_count && tif_need_resched(); } -static inline bool should_resched(int preempt_offset) +static __always_inline bool should_resched(int preempt_offset) { return unlikely(preempt_count() == preempt_offset && tif_need_resched()); |