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| author | Jonathan Corbet <corbet@lwn.net> | 2020-10-28 11:42:55 -0600 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2020-10-28 11:42:55 -0600 |
| commit | 6fee9372e0af63f557ad234663d8248f3caefc37 (patch) | |
| tree | 1f3ab8d7009d54badbad1b17dfd31794ae500750 /include/linux/refcount.h | |
| parent | e051955977b7e26124aa8c8398278145f85f94e8 (diff) | |
| parent | afc74ce7b484da5c5698d8eb2472a58c547cbc2b (diff) | |
| download | lwn-docs-5.10-warnings.tar.gz lwn-docs-5.10-warnings.zip | |
Merge branch 'mauro-warnings' into docs-nextdocs-5.10-warnings
Mauro says:
This series contain the patches from a previous series I sent:
[PATCH v2 00/24] Documentation build fixes against next-20201013
Plus other patches I sent later, against other versions of linux-next between
20201013 and v5.10-rc1.
It fixes most of the remaining documentation build warnings.
There were some changes from v2, as I changed some patches due to the
feedback received, and added reviewed-by/acked-by to several of them.
After this series, there will be just 3 warnings at include/kunit/test.h, whose
fixes were already applied by Shuah via her tree at linux-next. Hopefully, she
will be sending it upstream anytime toon. So, I dropped the fix from my trees.
The vast majority of patches here are also on my linux-next tree, as my
original plan were to send them upstream by the end of the merge window.
I'll drop from it once they get merged.
As those patches are fixes, I guess it should be ok to get them merged for
-rc2 or -rc3.
[jc: removed DRM and JBD patches applied elsewhere]
Diffstat (limited to 'include/linux/refcount.h')
| -rw-r--r-- | include/linux/refcount.h | 130 |
1 files changed, 65 insertions, 65 deletions
diff --git a/include/linux/refcount.h b/include/linux/refcount.h index 7fabb1af18e0..497990c69b0b 100644 --- a/include/linux/refcount.h +++ b/include/linux/refcount.h @@ -147,24 +147,6 @@ static inline unsigned int refcount_read(const refcount_t *r) return atomic_read(&r->refs); } -/** - * refcount_add_not_zero - add a value to a refcount unless it is 0 - * @i: the value to add to the refcount - * @r: the refcount - * - * Will saturate at REFCOUNT_SATURATED and WARN. - * - * Provides no memory ordering, it is assumed the caller has guaranteed the - * object memory to be stable (RCU, etc.). It does provide a control dependency - * and thereby orders future stores. See the comment on top. - * - * Use of this function is not recommended for the normal reference counting - * use case in which references are taken and released one at a time. In these - * cases, refcount_inc(), or one of its variants, should instead be used to - * increment a reference count. - * - * Return: false if the passed refcount is 0, true otherwise - */ static inline __must_check bool __refcount_add_not_zero(int i, refcount_t *r, int *oldp) { int old = refcount_read(r); @@ -183,17 +165,12 @@ static inline __must_check bool __refcount_add_not_zero(int i, refcount_t *r, in return old; } -static inline __must_check bool refcount_add_not_zero(int i, refcount_t *r) -{ - return __refcount_add_not_zero(i, r, NULL); -} - /** - * refcount_add - add a value to a refcount + * refcount_add_not_zero - add a value to a refcount unless it is 0 * @i: the value to add to the refcount * @r: the refcount * - * Similar to atomic_add(), but will saturate at REFCOUNT_SATURATED and WARN. + * Will saturate at REFCOUNT_SATURATED and WARN. * * Provides no memory ordering, it is assumed the caller has guaranteed the * object memory to be stable (RCU, etc.). It does provide a control dependency @@ -203,7 +180,14 @@ static inline __must_check bool refcount_add_not_zero(int i, refcount_t *r) * use case in which references are taken and released one at a time. In these * cases, refcount_inc(), or one of its variants, should instead be used to * increment a reference count. + * + * Return: false if the passed refcount is 0, true otherwise */ +static inline __must_check bool refcount_add_not_zero(int i, refcount_t *r) +{ + return __refcount_add_not_zero(i, r, NULL); +} + static inline void __refcount_add(int i, refcount_t *r, int *oldp) { int old = atomic_fetch_add_relaxed(i, &r->refs); @@ -217,11 +201,32 @@ static inline void __refcount_add(int i, refcount_t *r, int *oldp) refcount_warn_saturate(r, REFCOUNT_ADD_OVF); } +/** + * refcount_add - add a value to a refcount + * @i: the value to add to the refcount + * @r: the refcount + * + * Similar to atomic_add(), but will saturate at REFCOUNT_SATURATED and WARN. + * + * Provides no memory ordering, it is assumed the caller has guaranteed the + * object memory to be stable (RCU, etc.). It does provide a control dependency + * and thereby orders future stores. See the comment on top. + * + * Use of this function is not recommended for the normal reference counting + * use case in which references are taken and released one at a time. In these + * cases, refcount_inc(), or one of its variants, should instead be used to + * increment a reference count. + */ static inline void refcount_add(int i, refcount_t *r) { __refcount_add(i, r, NULL); } +static inline __must_check bool __refcount_inc_not_zero(refcount_t *r, int *oldp) +{ + return __refcount_add_not_zero(1, r, oldp); +} + /** * refcount_inc_not_zero - increment a refcount unless it is 0 * @r: the refcount to increment @@ -235,14 +240,14 @@ static inline void refcount_add(int i, refcount_t *r) * * Return: true if the increment was successful, false otherwise */ -static inline __must_check bool __refcount_inc_not_zero(refcount_t *r, int *oldp) +static inline __must_check bool refcount_inc_not_zero(refcount_t *r) { - return __refcount_add_not_zero(1, r, oldp); + return __refcount_inc_not_zero(r, NULL); } -static inline __must_check bool refcount_inc_not_zero(refcount_t *r) +static inline void __refcount_inc(refcount_t *r, int *oldp) { - return __refcount_inc_not_zero(r, NULL); + __refcount_add(1, r, oldp); } /** @@ -257,14 +262,27 @@ static inline __must_check bool refcount_inc_not_zero(refcount_t *r) * Will WARN if the refcount is 0, as this represents a possible use-after-free * condition. */ -static inline void __refcount_inc(refcount_t *r, int *oldp) +static inline void refcount_inc(refcount_t *r) { - __refcount_add(1, r, oldp); + __refcount_inc(r, NULL); } -static inline void refcount_inc(refcount_t *r) +static inline __must_check bool __refcount_sub_and_test(int i, refcount_t *r, int *oldp) { - __refcount_inc(r, NULL); + int old = atomic_fetch_sub_release(i, &r->refs); + + if (oldp) + *oldp = old; + + if (old == i) { + smp_acquire__after_ctrl_dep(); + return true; + } + + if (unlikely(old < 0 || old - i < 0)) + refcount_warn_saturate(r, REFCOUNT_SUB_UAF); + + return false; } /** @@ -287,27 +305,14 @@ static inline void refcount_inc(refcount_t *r) * * Return: true if the resulting refcount is 0, false otherwise */ -static inline __must_check bool __refcount_sub_and_test(int i, refcount_t *r, int *oldp) +static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r) { - int old = atomic_fetch_sub_release(i, &r->refs); - - if (oldp) - *oldp = old; - - if (old == i) { - smp_acquire__after_ctrl_dep(); - return true; - } - - if (unlikely(old < 0 || old - i < 0)) - refcount_warn_saturate(r, REFCOUNT_SUB_UAF); - - return false; + return __refcount_sub_and_test(i, r, NULL); } -static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r) +static inline __must_check bool __refcount_dec_and_test(refcount_t *r, int *oldp) { - return __refcount_sub_and_test(i, r, NULL); + return __refcount_sub_and_test(1, r, oldp); } /** @@ -323,26 +328,11 @@ static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r) * * Return: true if the resulting refcount is 0, false otherwise */ -static inline __must_check bool __refcount_dec_and_test(refcount_t *r, int *oldp) -{ - return __refcount_sub_and_test(1, r, oldp); -} - static inline __must_check bool refcount_dec_and_test(refcount_t *r) { return __refcount_dec_and_test(r, NULL); } -/** - * refcount_dec - decrement a refcount - * @r: the refcount - * - * Similar to atomic_dec(), it will WARN on underflow and fail to decrement - * when saturated at REFCOUNT_SATURATED. - * - * Provides release memory ordering, such that prior loads and stores are done - * before. - */ static inline void __refcount_dec(refcount_t *r, int *oldp) { int old = atomic_fetch_sub_release(1, &r->refs); @@ -354,6 +344,16 @@ static inline void __refcount_dec(refcount_t *r, int *oldp) refcount_warn_saturate(r, REFCOUNT_DEC_LEAK); } +/** + * refcount_dec - decrement a refcount + * @r: the refcount + * + * Similar to atomic_dec(), it will WARN on underflow and fail to decrement + * when saturated at REFCOUNT_SATURATED. + * + * Provides release memory ordering, such that prior loads and stores are done + * before. + */ static inline void refcount_dec(refcount_t *r) { __refcount_dec(r, NULL); |