Hello everyone, the following patch removes the use of int
cpus_nonempty variable from 'update_flag' function.
Thanks.
Signed-off-by: Md.Rakib H. Mullick ([email protected])
--- linux-2.6.27-rc2.orig/kernel/cpuset.c 2008-08-06 16:23:26.000000000 +0600
+++ linux-2.6.27-rc2/kernel/cpuset.c 2008-08-06 18:03:50.000000000 +0600
@@ -1110,7 +1110,7 @@ static int update_flag(cpuset_flagbits_t
{
struct cpuset trialcs;
int err;
- int cpus_nonempty, balance_flag_changed;
+ int balance_flag_changed;
trialcs = *cs;
if (turning_on)
@@ -1122,7 +1122,6 @@ static int update_flag(cpuset_flagbits_t
if (err < 0)
return err;
- cpus_nonempty = !cpus_empty(trialcs.cpus_allowed);
balance_flag_changed = (is_sched_load_balance(cs) !=
is_sched_load_balance(&trialcs));
@@ -1130,7 +1129,7 @@ static int update_flag(cpuset_flagbits_t
cs->flags = trialcs.flags;
mutex_unlock(&callback_mutex);
- if (cpus_nonempty && balance_flag_changed)
+ if (!cpus_empty(trialcs.cpus_allowed) && balance_flag_changed)
rebuild_sched_domains();
return 0;
Rabik wrote:
> removes ... cpus_nonempty variable
No.
Sorry - I must NAQ this patch. I intentionally add inessential
variables such as this in order to make the code easier to read.
I consider the line of code:
if (cpus_nonempty && balance_flag_changed)
to be more readable than the line of clde:
if (!cpus_empty(trialcs.cpus_allowed) && balance_flag_changed)
--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <[email protected]> 1.940.382.4214
Andrew - I reverse my 'NAQ' on this patch.
Acked-by: Paul Jackson <[email protected]>
Rakib wrote:
> I think we should concentrate on how it will be executed.
Aha - you're right. Your patch saves 12 bytes of kernel
text space (x86_64 arch). I had assumed that the compiler
would optimize my inessential cpus_nonempty variable out of
existence, but that is not the case.
Thanks for persuing this, Rakib.
--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <[email protected]> 1.940.382.4214