| Message ID | 20241015161112.442758-11-paulmck@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 74a0d84a2291cac7a137bbe9b1af0ff2fe823b51 |
| Headers | show |
| Series | SRCU-lite changes for v6.13 | expand |
On 10/15/2024 9:41 PM, Paul E. McKenney wrote: > This commit adds an rcutorture.reader_flavor parameter whose bits > correspond to reader flavors. For example, SRCU's readers are 0x1 for > normal and 0x2 for NMI-safe. > > Signed-off-by: Paul E. McKenney <paulmck@kernel.org> > Cc: Alexei Starovoitov <ast@kernel.org> > Cc: Andrii Nakryiko <andrii@kernel.org> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Kent Overstreet <kent.overstreet@linux.dev> > Cc: <bpf@vger.kernel.org> > --- > .../admin-guide/kernel-parameters.txt | 8 +++++ > kernel/rcu/rcutorture.c | 30 ++++++++++++++----- > 2 files changed, 30 insertions(+), 8 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 1518343bbe223..52922727006fc 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -5426,6 +5426,14 @@ > The delay, in seconds, between successive > read-then-exit testing episodes. > > + rcutorture.reader_flavor= [KNL] > + A bit mask indicating which readers to use. > + If there is more than one bit set, the readers > + are entered from low-order bit up, and are > + exited in the opposite order. For SRCU, the > + 0x1 bit is normal readers and the 0x2 bit is > + for NMI-safe readers. > + > rcutorture.shuffle_interval= [KNL] > Set task-shuffle interval (s). Shuffling tasks > allows some CPUs to go into dyntick-idle mode > diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c > index f96ab98f8182f..405decec33677 100644 > --- a/kernel/rcu/rcutorture.c > +++ b/kernel/rcu/rcutorture.c > @@ -111,6 +111,7 @@ torture_param(int, nocbs_nthreads, 0, "Number of NOCB toggle threads, 0 to disab > torture_param(int, nocbs_toggle, 1000, "Time between toggling nocb state (ms)"); > torture_param(int, read_exit_delay, 13, "Delay between read-then-exit episodes (s)"); > torture_param(int, read_exit_burst, 16, "# of read-then-exit bursts per episode, zero to disable"); > +torture_param(int, reader_flavor, 0x1, "Reader flavors to use, one per bit."); > torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles"); > torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable."); > torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable."); > @@ -644,10 +645,20 @@ static void srcu_get_gp_data(int *flags, unsigned long *gp_seq) > > static int srcu_torture_read_lock(void) > { > - if (cur_ops == &srcud_ops) > - return srcu_read_lock_nmisafe(srcu_ctlp); > - else > - return srcu_read_lock(srcu_ctlp); > + int idx; > + int ret = 0; > + > + if ((reader_flavor & 0x1) || !(reader_flavor & 0x7)) { Minor: Maybe use macros in place of 0x1, 0x2, 0x7 as a cleanup later. - Neeraj > + idx = srcu_read_lock(srcu_ctlp); > + WARN_ON_ONCE(idx & ~0x1); > + ret += idx; > + } > + if (reader_flavor & 0x2) { > + idx = srcu_read_lock_nmisafe(srcu_ctlp); > + WARN_ON_ONCE(idx & ~0x1); > + ret += idx << 1; > + } > + return ret; > } >
On Tue, Nov 12, 2024 at 10:12:40AM +0530, Neeraj Upadhyay wrote: > On 10/15/2024 9:41 PM, Paul E. McKenney wrote: > > This commit adds an rcutorture.reader_flavor parameter whose bits > > correspond to reader flavors. For example, SRCU's readers are 0x1 for > > normal and 0x2 for NMI-safe. > > > > Signed-off-by: Paul E. McKenney <paulmck@kernel.org> > > Cc: Alexei Starovoitov <ast@kernel.org> > > Cc: Andrii Nakryiko <andrii@kernel.org> > > Cc: Peter Zijlstra <peterz@infradead.org> > > Cc: Kent Overstreet <kent.overstreet@linux.dev> > > Cc: <bpf@vger.kernel.org> > > --- > > .../admin-guide/kernel-parameters.txt | 8 +++++ > > kernel/rcu/rcutorture.c | 30 ++++++++++++++----- > > 2 files changed, 30 insertions(+), 8 deletions(-) > > > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > > index 1518343bbe223..52922727006fc 100644 > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -5426,6 +5426,14 @@ > > The delay, in seconds, between successive > > read-then-exit testing episodes. > > > > + rcutorture.reader_flavor= [KNL] > > + A bit mask indicating which readers to use. > > + If there is more than one bit set, the readers > > + are entered from low-order bit up, and are > > + exited in the opposite order. For SRCU, the > > + 0x1 bit is normal readers and the 0x2 bit is > > + for NMI-safe readers. > > + > > rcutorture.shuffle_interval= [KNL] > > Set task-shuffle interval (s). Shuffling tasks > > allows some CPUs to go into dyntick-idle mode > > diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c > > index f96ab98f8182f..405decec33677 100644 > > --- a/kernel/rcu/rcutorture.c > > +++ b/kernel/rcu/rcutorture.c > > @@ -111,6 +111,7 @@ torture_param(int, nocbs_nthreads, 0, "Number of NOCB toggle threads, 0 to disab > > torture_param(int, nocbs_toggle, 1000, "Time between toggling nocb state (ms)"); > > torture_param(int, read_exit_delay, 13, "Delay between read-then-exit episodes (s)"); > > torture_param(int, read_exit_burst, 16, "# of read-then-exit bursts per episode, zero to disable"); > > +torture_param(int, reader_flavor, 0x1, "Reader flavors to use, one per bit."); > > torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles"); > > torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable."); > > torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable."); > > @@ -644,10 +645,20 @@ static void srcu_get_gp_data(int *flags, unsigned long *gp_seq) > > > > static int srcu_torture_read_lock(void) > > { > > - if (cur_ops == &srcud_ops) > > - return srcu_read_lock_nmisafe(srcu_ctlp); > > - else > > - return srcu_read_lock(srcu_ctlp); > > + int idx; > > + int ret = 0; > > + > > + if ((reader_flavor & 0x1) || !(reader_flavor & 0x7)) { > > Minor: Maybe use macros in place of 0x1, 0x2, 0x7 as a cleanup later. Hmmm... I could move SRCU_READ_FLAVOR_* to include/linux/srcu.h and make rcutorture use those. Plus have a combined mask for the instances of 0x7. Or is there a better way? Thanx, Paul > - Neeraj > > > + idx = srcu_read_lock(srcu_ctlp); > > + WARN_ON_ONCE(idx & ~0x1); > > + ret += idx; > > + } > > + if (reader_flavor & 0x2) { > > + idx = srcu_read_lock_nmisafe(srcu_ctlp); > > + WARN_ON_ONCE(idx & ~0x1); > > + ret += idx << 1; > > + } > > + return ret; > > } > > >
>>> >>> static int srcu_torture_read_lock(void) >>> { >>> - if (cur_ops == &srcud_ops) >>> - return srcu_read_lock_nmisafe(srcu_ctlp); >>> - else >>> - return srcu_read_lock(srcu_ctlp); >>> + int idx; >>> + int ret = 0; >>> + >>> + if ((reader_flavor & 0x1) || !(reader_flavor & 0x7)) { >> >> Minor: Maybe use macros in place of 0x1, 0x2, 0x7 as a cleanup later. > > Hmmm... > > I could move SRCU_READ_FLAVOR_* to include/linux/srcu.h and make > rcutorture use those. Plus have a combined mask for the instances of 0x7. > > Or is there a better way? > Yes, I was thinking the same. This looks good. - Neeraj
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 1518343bbe223..52922727006fc 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5426,6 +5426,14 @@ The delay, in seconds, between successive read-then-exit testing episodes. + rcutorture.reader_flavor= [KNL] + A bit mask indicating which readers to use. + If there is more than one bit set, the readers + are entered from low-order bit up, and are + exited in the opposite order. For SRCU, the + 0x1 bit is normal readers and the 0x2 bit is + for NMI-safe readers. + rcutorture.shuffle_interval= [KNL] Set task-shuffle interval (s). Shuffling tasks allows some CPUs to go into dyntick-idle mode diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index f96ab98f8182f..405decec33677 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -111,6 +111,7 @@ torture_param(int, nocbs_nthreads, 0, "Number of NOCB toggle threads, 0 to disab torture_param(int, nocbs_toggle, 1000, "Time between toggling nocb state (ms)"); torture_param(int, read_exit_delay, 13, "Delay between read-then-exit episodes (s)"); torture_param(int, read_exit_burst, 16, "# of read-then-exit bursts per episode, zero to disable"); +torture_param(int, reader_flavor, 0x1, "Reader flavors to use, one per bit."); torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles"); torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable."); torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable."); @@ -644,10 +645,20 @@ static void srcu_get_gp_data(int *flags, unsigned long *gp_seq) static int srcu_torture_read_lock(void) { - if (cur_ops == &srcud_ops) - return srcu_read_lock_nmisafe(srcu_ctlp); - else - return srcu_read_lock(srcu_ctlp); + int idx; + int ret = 0; + + if ((reader_flavor & 0x1) || !(reader_flavor & 0x7)) { + idx = srcu_read_lock(srcu_ctlp); + WARN_ON_ONCE(idx & ~0x1); + ret += idx; + } + if (reader_flavor & 0x2) { + idx = srcu_read_lock_nmisafe(srcu_ctlp); + WARN_ON_ONCE(idx & ~0x1); + ret += idx << 1; + } + return ret; } static void @@ -671,10 +682,11 @@ srcu_read_delay(struct torture_random_state *rrsp, struct rt_read_seg *rtrsp) static void srcu_torture_read_unlock(int idx) { - if (cur_ops == &srcud_ops) - srcu_read_unlock_nmisafe(srcu_ctlp, idx); - else - srcu_read_unlock(srcu_ctlp, idx); + WARN_ON_ONCE((reader_flavor && (idx & ~reader_flavor)) || (!reader_flavor && (idx & ~0x1))); + if (reader_flavor & 0x2) + srcu_read_unlock_nmisafe(srcu_ctlp, (idx & 0x2) >> 1); + if ((reader_flavor & 0x1) || !(reader_flavor & 0x7)) + srcu_read_unlock(srcu_ctlp, idx & 0x1); } static int torture_srcu_read_lock_held(void) @@ -2389,6 +2401,7 @@ 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 " + "reader_flavor=%x " "nocbs_nthreads=%d nocbs_toggle=%d " "test_nmis=%d\n", torture_type, tag, nrealreaders, nfakewriters, @@ -2401,6 +2414,7 @@ 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, + reader_flavor, nocbs_nthreads, nocbs_toggle, test_nmis); }
This commit adds an rcutorture.reader_flavor parameter whose bits correspond to reader flavors. For example, SRCU's readers are 0x1 for normal and 0x2 for NMI-safe. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: <bpf@vger.kernel.org> --- .../admin-guide/kernel-parameters.txt | 8 +++++ kernel/rcu/rcutorture.c | 30 ++++++++++++++----- 2 files changed, 30 insertions(+), 8 deletions(-)