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> --- 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; -- 2.24.0.432.g9d3f5f5b63-goog
