On 11/26/19 6:04 AM, Marco Elver wrote: > Prefer __always_inline for fast-path functions that are called outside > of user_access_save, to avoid generating UACCESS warnings when > optimizing for size (CC_OPTIMIZE_FOR_SIZE). It will also avoid future > surprises with compiler versions that change the inlining heuristic even > when optimizing for performance. > > Report: http://lkml.kernel.org/r/58708908-84a0-0a81-a836-ad97e33dbb62@xxxxxxxxxxxxx > Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> > Signed-off-by: Marco Elver <elver@xxxxxxxxxx> Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> # build-tested Thanks. > --- > Rebased on: locking/kcsan branch of tip tree. > --- > kernel/kcsan/atomic.h | 2 +- > kernel/kcsan/core.c | 16 +++++++--------- > kernel/kcsan/encoding.h | 14 +++++++------- > 3 files changed, 15 insertions(+), 17 deletions(-) > > diff --git a/kernel/kcsan/atomic.h b/kernel/kcsan/atomic.h > index 576e03ddd6a3..a9c193053491 100644 > --- a/kernel/kcsan/atomic.h > +++ b/kernel/kcsan/atomic.h > @@ -18,7 +18,7 @@ > * than cast to volatile. Eventually, we hope to be able to remove this > * function. > */ > -static inline bool kcsan_is_atomic(const volatile void *ptr) > +static __always_inline bool kcsan_is_atomic(const volatile void *ptr) > { > /* only jiffies for now */ > return ptr == &jiffies; > diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c > index 3314fc29e236..c616fec639cd 100644 > --- a/kernel/kcsan/core.c > +++ b/kernel/kcsan/core.c > @@ -78,10 +78,8 @@ static atomic_long_t watchpoints[CONFIG_KCSAN_NUM_WATCHPOINTS + NUM_SLOTS-1]; > */ > static DEFINE_PER_CPU(long, kcsan_skip); > > -static inline atomic_long_t *find_watchpoint(unsigned long addr, > - size_t size, > - bool expect_write, > - long *encoded_watchpoint) > +static __always_inline atomic_long_t * > +find_watchpoint(unsigned long addr, size_t size, bool expect_write, long *encoded_watchpoint) > { > const int slot = watchpoint_slot(addr); > const unsigned long addr_masked = addr & WATCHPOINT_ADDR_MASK; > @@ -146,7 +144,7 @@ insert_watchpoint(unsigned long addr, size_t size, bool is_write) > * 2. the thread that set up the watchpoint already removed it; > * 3. the watchpoint was removed and then re-used. > */ > -static inline bool > +static __always_inline bool > try_consume_watchpoint(atomic_long_t *watchpoint, long encoded_watchpoint) > { > return atomic_long_try_cmpxchg_relaxed(watchpoint, &encoded_watchpoint, CONSUMED_WATCHPOINT); > @@ -160,7 +158,7 @@ static inline bool remove_watchpoint(atomic_long_t *watchpoint) > return atomic_long_xchg_relaxed(watchpoint, INVALID_WATCHPOINT) != CONSUMED_WATCHPOINT; > } > > -static inline struct kcsan_ctx *get_ctx(void) > +static __always_inline struct kcsan_ctx *get_ctx(void) > { > /* > * In interrupts, use raw_cpu_ptr to avoid unnecessary checks, that would > @@ -169,7 +167,7 @@ static inline struct kcsan_ctx *get_ctx(void) > return in_task() ? ¤t->kcsan_ctx : raw_cpu_ptr(&kcsan_cpu_ctx); > } > > -static inline bool is_atomic(const volatile void *ptr) > +static __always_inline bool is_atomic(const volatile void *ptr) > { > struct kcsan_ctx *ctx = get_ctx(); > > @@ -193,7 +191,7 @@ static inline bool is_atomic(const volatile void *ptr) > return kcsan_is_atomic(ptr); > } > > -static inline bool should_watch(const volatile void *ptr, int type) > +static __always_inline bool should_watch(const volatile void *ptr, int type) > { > /* > * Never set up watchpoints when memory operations are atomic. > @@ -226,7 +224,7 @@ static inline void reset_kcsan_skip(void) > this_cpu_write(kcsan_skip, skip_count); > } > > -static inline bool kcsan_is_enabled(void) > +static __always_inline bool kcsan_is_enabled(void) > { > return READ_ONCE(kcsan_enabled) && get_ctx()->disable_count == 0; > } > diff --git a/kernel/kcsan/encoding.h b/kernel/kcsan/encoding.h > index b63890e86449..f03562aaf2eb 100644 > --- a/kernel/kcsan/encoding.h > +++ b/kernel/kcsan/encoding.h > @@ -59,10 +59,10 @@ encode_watchpoint(unsigned long addr, size_t size, bool is_write) > (addr & WATCHPOINT_ADDR_MASK)); > } > > -static inline bool decode_watchpoint(long watchpoint, > - unsigned long *addr_masked, > - size_t *size, > - bool *is_write) > +static __always_inline bool decode_watchpoint(long watchpoint, > + unsigned long *addr_masked, > + size_t *size, > + bool *is_write) > { > if (watchpoint == INVALID_WATCHPOINT || > watchpoint == CONSUMED_WATCHPOINT) > @@ -78,13 +78,13 @@ static inline bool decode_watchpoint(long watchpoint, > /* > * Return watchpoint slot for an address. > */ > -static inline int watchpoint_slot(unsigned long addr) > +static __always_inline int watchpoint_slot(unsigned long addr) > { > return (addr / PAGE_SIZE) % CONFIG_KCSAN_NUM_WATCHPOINTS; > } > > -static inline bool matching_access(unsigned long addr1, size_t size1, > - unsigned long addr2, size_t size2) > +static __always_inline bool matching_access(unsigned long addr1, size_t size1, > + unsigned long addr2, size_t size2) > { > unsigned long end_range1 = addr1 + size1 - 1; > unsigned long end_range2 = addr2 + size2 - 1; > -- ~Randy
