| Message ID | 20230202064846.3306975-1-qiang1.zhang@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | rcutorture: Create nocb tasks only for CONFIG_RCU_NOCB_CPU=y kernels | expand |
>When setting nocbs_nthreads to start rcutorture test with a non-zero value, >the nocb tasks will be created and invoke rcu_nocb_cpu_offload/deoffload() >to toggle CPU's callback-offload state, but for CONFIG_RCU_NOCB_CPU=n >kernel, the rcu_nocb_cpu_offload/deoffload() is a no-op and this is also >meaningless for torture_type is non-rcu. > >This commit therefore add member can_nocbs_toggle to rcu_torture_ops >structure to avoid unnecessary nocb tasks creation. > >Signed-off-by: Zqiang <qiang1.zhang@intel.com> >--- > kernel/rcu/rcutorture.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > >diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c >index 297da28ce92d..27becacbe3b2 100644 >--- a/kernel/rcu/rcutorture.c >+++ b/kernel/rcu/rcutorture.c >@@ -383,6 +383,7 @@ struct rcu_torture_ops { > long cbflood_max; > int irq_capable; > int can_boost; >+ int can_nocbs_toggle; > int extendables; > int slow_gps; > int no_pi_lock; >@@ -569,6 +570,7 @@ static struct rcu_torture_ops rcu_ops = { > .stall_dur = rcu_jiffies_till_stall_check, > .irq_capable = 1, > .can_boost = IS_ENABLED(CONFIG_RCU_BOOST), >+ .can_nocbs_toggle = IS_ENABLED(CONFIG_RCU_NOCB_CPU), > .extendables = RCUTORTURE_MAX_EXTEND, > .name = "rcu" > }; >@@ -2356,7 +2358,7 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) > "n_barrier_cbs=%d " > "onoff_interval=%d onoff_holdoff=%d " > "read_exit_delay=%d read_exit_burst=%d " >- "nocbs_nthreads=%d nocbs_toggle=%d " >+ "nocbs_nthreads=%d/%d nocbs_toggle=%d " > "test_nmis=%d\n", > torture_type, tag, nrealreaders, nfakewriters, > stat_interval, verbose, test_no_idle_hz, shuffle_interval, >@@ -2368,7 +2370,7 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) > n_barrier_cbs, > onoff_interval, onoff_holdoff, > read_exit_delay, read_exit_burst, >- nocbs_nthreads, nocbs_toggle, >+ nocbs_nthreads, cur_ops->can_nocbs_toggle, nocbs_toggle, > test_nmis); > } > >@@ -3708,6 +3710,10 @@ rcu_torture_init(void) > pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); > fqs_duration = 0; > } >+ if (!cur_ops->can_nocbs_toggle && nocbs_nthreads > 0) { >+ pr_alert("rcu-torture: ->can_nocbs_toggle false and non-zero nocbs_nthreads, nocbs_toggle disabled.\n"); >+ nocbs_nthreads = 0; >+ } Sorry, I ignored the case where the nocbs_nthreads is set to a negative value, will resend. > if (cur_ops->init) > cur_ops->init(); > >-- 2.25.1
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 297da28ce92d..27becacbe3b2 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -383,6 +383,7 @@ struct rcu_torture_ops { long cbflood_max; int irq_capable; int can_boost; + int can_nocbs_toggle; int extendables; int slow_gps; int no_pi_lock; @@ -569,6 +570,7 @@ static struct rcu_torture_ops rcu_ops = { .stall_dur = rcu_jiffies_till_stall_check, .irq_capable = 1, .can_boost = IS_ENABLED(CONFIG_RCU_BOOST), + .can_nocbs_toggle = IS_ENABLED(CONFIG_RCU_NOCB_CPU), .extendables = RCUTORTURE_MAX_EXTEND, .name = "rcu" }; @@ -2356,7 +2358,7 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) "n_barrier_cbs=%d " "onoff_interval=%d onoff_holdoff=%d " "read_exit_delay=%d read_exit_burst=%d " - "nocbs_nthreads=%d nocbs_toggle=%d " + "nocbs_nthreads=%d/%d nocbs_toggle=%d " "test_nmis=%d\n", torture_type, tag, nrealreaders, nfakewriters, stat_interval, verbose, test_no_idle_hz, shuffle_interval, @@ -2368,7 +2370,7 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) n_barrier_cbs, onoff_interval, onoff_holdoff, read_exit_delay, read_exit_burst, - nocbs_nthreads, nocbs_toggle, + nocbs_nthreads, cur_ops->can_nocbs_toggle, nocbs_toggle, test_nmis); } @@ -3708,6 +3710,10 @@ rcu_torture_init(void) pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); fqs_duration = 0; } + if (!cur_ops->can_nocbs_toggle && nocbs_nthreads > 0) { + pr_alert("rcu-torture: ->can_nocbs_toggle false and non-zero nocbs_nthreads, nocbs_toggle disabled.\n"); + nocbs_nthreads = 0; + } if (cur_ops->init) cur_ops->init();
When setting nocbs_nthreads to start rcutorture test with a non-zero value, the nocb tasks will be created and invoke rcu_nocb_cpu_offload/deoffload() to toggle CPU's callback-offload state, but for CONFIG_RCU_NOCB_CPU=n kernel, the rcu_nocb_cpu_offload/deoffload() is a no-op and this is also meaningless for torture_type is non-rcu. This commit therefore add member can_nocbs_toggle to rcu_torture_ops structure to avoid unnecessary nocb tasks creation. Signed-off-by: Zqiang <qiang1.zhang@intel.com> --- kernel/rcu/rcutorture.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)