Provide an accurate version of percpu_counter_read. Should we go and replace the current use of percpu_counter_sum() with percpu_counter_sum_positive(), and call this new primitive percpu_counter_sum() instead? Signed-off-by: Peter Zijlstra --- include/linux/percpu_counter.h | 18 +++++++++++++++++- lib/percpu_counter.c | 6 +++--- 2 files changed, 20 insertions(+), 4 deletions(-) Index: linux-2.6/include/linux/percpu_counter.h =================================================================== --- linux-2.6.orig/include/linux/percpu_counter.h 2007-05-02 19:43:34.000000000 +0200 +++ linux-2.6/include/linux/percpu_counter.h 2007-05-04 09:42:47.000000000 +0200 @@ -41,7 +41,18 @@ static inline void percpu_counter_destro void percpu_counter_set(struct percpu_counter *fbc, s64 amount); void __percpu_counter_mod(struct percpu_counter *fbc, s32 amount, s32 batch); void __percpu_counter_mod64(struct percpu_counter *fbc, s64 amount, s32 batch); -s64 percpu_counter_sum(struct percpu_counter *fbc); +s64 __percpu_counter_sum(struct percpu_counter *fbc); + +static inline s64 percpu_counter_sum(struct percpu_counter *fbc) +{ + s64 ret = __percpu_counter_sum(fbc); + return ret < 0 ? 0 : ret; +} + +static inline s64 percpu_counter_sum_signed(struct percpu_counter *fbc) +{ + return __percpu_counter_sum(fbc); +} static inline void percpu_counter_mod(struct percpu_counter *fbc, s32 amount) { @@ -130,6 +141,11 @@ static inline s64 percpu_counter_sum(str return percpu_counter_read_positive(fbc); } +static inline s64 percpu_counter_sum_signed(struct percpu_counter *fbc) +{ + return fbc->count; +} + #endif /* CONFIG_SMP */ static inline void percpu_counter_inc(struct percpu_counter *fbc) Index: linux-2.6/lib/percpu_counter.c =================================================================== --- linux-2.6.orig/lib/percpu_counter.c 2007-05-02 19:43:34.000000000 +0200 +++ linux-2.6/lib/percpu_counter.c 2007-05-04 09:38:36.000000000 +0200 @@ -62,7 +62,7 @@ EXPORT_SYMBOL(__percpu_counter_mod64); * Add up all the per-cpu counts, return the result. This is a more accurate * but much slower version of percpu_counter_read_positive() */ -s64 percpu_counter_sum(struct percpu_counter *fbc) +s64 __percpu_counter_sum(struct percpu_counter *fbc) { s64 ret; int cpu; @@ -74,6 +74,6 @@ s64 percpu_counter_sum(struct percpu_cou ret += *pcount; } spin_unlock(&fbc->lock); - return ret < 0 ? 0 : ret; + return ret; } -EXPORT_SYMBOL(percpu_counter_sum); +EXPORT_SYMBOL(__percpu_counter_sum); -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/