Re: [PATCH]cputime: make bool type for steal ticks
2013/1/26 Joe Perches : > On Sat, 2013-01-26 at 01:45 +0100, Frederic Weisbecker wrote: >> > diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c > [] >> > @@ -282,7 +282,7 @@ static __always_inline bool >> > steal_account_process_tick(void) > [] >> > - return st; >> > + return !!st; >> >> I would expect gcc to perform the semantic "!!" cast implicitly. I >> just did some basic tests locally and it does. >> I prefer to be paranoid and not do any assumption though, unless I'm >> told gcc always guarantees this correct implicit cast. I'm queuing >> this patch and will send it to Ingo. > > It's unnecessary. > > 6.3.1.2p1: > > "When any scalar value is converted to _Bool, the result is 0 > if the value compares equal to 0; otherwise, the result is 1." Ok then I'll ignore this patch. If somebody oppose, raise your hand. Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH]cputime: make bool type for steal ticks
2013/1/26 Joe Perches j...@perches.com: On Sat, 2013-01-26 at 01:45 +0100, Frederic Weisbecker wrote: diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c [] @@ -282,7 +282,7 @@ static __always_inline bool steal_account_process_tick(void) [] - return st; + return !!st; I would expect gcc to perform the semantic !! cast implicitly. I just did some basic tests locally and it does. I prefer to be paranoid and not do any assumption though, unless I'm told gcc always guarantees this correct implicit cast. I'm queuing this patch and will send it to Ingo. It's unnecessary. 6.3.1.2p1: When any scalar value is converted to _Bool, the result is 0 if the value compares equal to 0; otherwise, the result is 1. Ok then I'll ignore this patch. If somebody oppose, raise your hand. Thanks. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH]cputime: make bool type for steal ticks
On Sat, 2013-01-26 at 01:45 +0100, Frederic Weisbecker wrote: > > diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c [] > > @@ -282,7 +282,7 @@ static __always_inline bool > > steal_account_process_tick(void) [] > > - return st; > > + return !!st; > > I would expect gcc to perform the semantic "!!" cast implicitly. I > just did some basic tests locally and it does. > I prefer to be paranoid and not do any assumption though, unless I'm > told gcc always guarantees this correct implicit cast. I'm queuing > this patch and will send it to Ingo. It's unnecessary. 6.3.1.2p1: "When any scalar value is converted to _Bool, the result is 0 if the value compares equal to 0; otherwise, the result is 1." -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH]cputime: make bool type for steal ticks
2012/11/16 liguang : > Signed-off-by: liguang > --- > kernel/sched/cputime.c |2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c > index 81b763b..d2c24c1 100644 > --- a/kernel/sched/cputime.c > +++ b/kernel/sched/cputime.c > @@ -282,7 +282,7 @@ static __always_inline bool > steal_account_process_tick(void) > this_rq()->prev_steal_time += st * TICK_NSEC; > > account_steal_time(st); > - return st; > + return !!st; I would expect gcc to perform the semantic "!!" cast implicitly. I just did some basic tests locally and it does. I prefer to be paranoid and not do any assumption though, unless I'm told gcc always guarantees this correct implicit cast. I'm queuing this patch and will send it to Ingo. Thanks! > } > #endif > return false; > -- > 1.7.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH]cputime: make bool type for steal ticks
2012/11/16 liguang lig.f...@cn.fujitsu.com: Signed-off-by: liguang lig.f...@cn.fujitsu.com --- kernel/sched/cputime.c |2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c index 81b763b..d2c24c1 100644 --- a/kernel/sched/cputime.c +++ b/kernel/sched/cputime.c @@ -282,7 +282,7 @@ static __always_inline bool steal_account_process_tick(void) this_rq()-prev_steal_time += st * TICK_NSEC; account_steal_time(st); - return st; + return !!st; I would expect gcc to perform the semantic !! cast implicitly. I just did some basic tests locally and it does. I prefer to be paranoid and not do any assumption though, unless I'm told gcc always guarantees this correct implicit cast. I'm queuing this patch and will send it to Ingo. Thanks! } #endif return false; -- 1.7.1 -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH]cputime: make bool type for steal ticks
On Sat, 2013-01-26 at 01:45 +0100, Frederic Weisbecker wrote: diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c [] @@ -282,7 +282,7 @@ static __always_inline bool steal_account_process_tick(void) [] - return st; + return !!st; I would expect gcc to perform the semantic !! cast implicitly. I just did some basic tests locally and it does. I prefer to be paranoid and not do any assumption though, unless I'm told gcc always guarantees this correct implicit cast. I'm queuing this patch and will send it to Ingo. It's unnecessary. 6.3.1.2p1: When any scalar value is converted to _Bool, the result is 0 if the value compares equal to 0; otherwise, the result is 1. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
