On Wed, Feb 26, 2025 at 10:04:35AM -0800, Paul E. McKenney wrote: > On Wed, Feb 26, 2025 at 12:49:41PM -0500, Joel Fernandes wrote: > > > > > > On 2/26/2025 9:29 AM, Uladzislau Rezki wrote: > > > On Tue, Feb 25, 2025 at 04:24:09PM -0500, Joel Fernandes wrote: > > >> On Tue, Feb 25, 2025 at 12:00:18PM +0100, Uladzislau Rezki (Sony) wrote: > > >>> Currently "nfakewriters" parameter can be set to any value but > > >>> there is no possibility to adjust it automatically based on how > > >>> many CPUs a system has where a test is run on. > > >>> > > >>> To address this, if the "nfakewriters" is set to negative it will > > >>> be adjusted to num_online_cpus() during torture initialization. > > >>> > > >>> Reviewed-by: Paul E. McKenney <paulmck@xxxxxxxxxx> > > >>> Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx> > > >>> --- > > >>> kernel/rcu/rcutorture.c | 22 ++++++++++++++++------ > > >>> 1 file changed, 16 insertions(+), 6 deletions(-) > > >>> > > >>> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c > > >>> index d98b3bd6d91f..f376262532ce 100644 > > >>> --- a/kernel/rcu/rcutorture.c > > >>> +++ b/kernel/rcu/rcutorture.c > > >>> @@ -148,6 +148,7 @@ MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, srcu, ...)"); > > >> > > >> IMO, this should also be updated to reflect the possibily to set it negative > > >> and hence to number CPUs: > > >> > > >> torture_param(int, nfakewriters, 4, "Number of RCU fake writer threads"); > > >> > > > You can set it to a negative as well as to number of CPUs or any other > > > number. > > Sorry I just meant amend the description to something like "Number of RCU fake > > writer threads (or set to -1 for NR_CPUs)", so user does not have to read code > > to know that (and update the kernel cmdline params document as well). > > Should we also adjust the string for nreaders? > Makes sense. Both options are adjusted in same way. -- Uladzislau Rezki
