From a48f3fad4f97fe6a2522fe2f5b3054b4c48a8eac Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 18 Mar 2014 15:57:41 -0700 Subject: [PATCH] rcutorture: Add tests for get_state_synchronize_rcu() This commit adds rcutorture testing for get_state_synchronize_rcu() and cond_synchronize_rcu(). Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcu/rcutorture.c | 130 +++++++++++++++++++++++++++++----------- 1 file changed, 95 insertions(+), 35 deletions(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index dfec2582899f..0d27b9cc14e4 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -58,6 +58,7 @@ torture_param(int, fqs_duration, 0, "Duration of fqs bursts (us), 0 to disable"); torture_param(int, fqs_holdoff, 0, "Holdoff time within fqs bursts (us)"); torture_param(int, fqs_stutter, 3, "Wait time between fqs bursts (s)"); +torture_param(bool, gp_cond, false, "Use conditional/async GP wait primitives"); torture_param(bool, gp_exp, false, "Use expedited GP wait primitives"); torture_param(bool, gp_normal, false, "Use normal (non-expedited) GP wait primitives"); @@ -144,8 +145,10 @@ static int rcu_torture_writer_state; #define RTWS_REPLACE 2 #define RTWS_DEF_FREE 3 #define RTWS_EXP_SYNC 4 -#define RTWS_STUTTER 5 -#define RTWS_STOPPING 6 +#define RTWS_COND_GET 5 +#define RTWS_COND_SYNC 6 +#define RTWS_STUTTER 7 +#define RTWS_STOPPING 8 #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) #define RCUTORTURE_RUNNABLE_INIT 1 @@ -232,6 +235,8 @@ struct rcu_torture_ops { void (*deferred_free)(struct rcu_torture *p); void (*sync)(void); void (*exp_sync)(void); + unsigned long (*get_state)(void); + void (*cond_sync)(unsigned long oldstate); void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); void (*cb_barrier)(void); void (*fqs)(void); @@ -283,10 +288,48 @@ static int rcu_torture_completed(void) return rcu_batches_completed(); } +/* + * Update callback in the pipe. This should be invoked after a grace period. + */ +static bool +rcu_torture_pipe_update_one(struct rcu_torture *rp) +{ + int i; + + i = rp->rtort_pipe_count; + if (i > RCU_TORTURE_PIPE_LEN) + i = RCU_TORTURE_PIPE_LEN; + atomic_inc(&rcu_torture_wcount[i]); + if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { + rp->rtort_mbtest = 0; + return true; + } + return false; +} + +/* + * Update all callbacks in the pipe. Suitable for synchronous grace-period + * primitives. + */ +static void +rcu_torture_pipe_update(struct rcu_torture *old_rp) +{ + struct rcu_torture *rp; + struct rcu_torture *rp1; + + if (old_rp) + list_add(&old_rp->rtort_free, &rcu_torture_removed); + list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { + if (rcu_torture_pipe_update_one(rp)) { + list_del(&rp->rtort_free); + rcu_torture_free(rp); + } + } +} + static void rcu_torture_cb(struct rcu_head *p) { - int i; struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); if (torture_must_stop_irq()) { @@ -294,16 +337,10 @@ rcu_torture_cb(struct rcu_head *p) /* The next initialization will pick up the pieces. */ return; } - i = rp->rtort_pipe_count; - if (i > RCU_TORTURE_PIPE_LEN) - i = RCU_TORTURE_PIPE_LEN; - atomic_inc(&rcu_torture_wcount[i]); - if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { - rp->rtort_mbtest = 0; + if (rcu_torture_pipe_update_one(rp)) rcu_torture_free(rp); - } else { + else cur_ops->deferred_free(rp); - } } static int rcu_no_completed(void) @@ -331,6 +368,8 @@ static struct rcu_torture_ops rcu_ops = { .deferred_free = rcu_torture_deferred_free, .sync = synchronize_rcu, .exp_sync = synchronize_rcu_expedited, + .get_state = get_state_synchronize_rcu, + .cond_sync = cond_synchronize_rcu, .call = call_rcu, .cb_barrier = rcu_barrier, .fqs = rcu_force_quiescent_state, @@ -705,16 +744,39 @@ rcu_torture_fqs(void *arg) static int rcu_torture_writer(void *arg) { - bool exp; + unsigned long gp_snap; + bool gp_cond1 = gp_cond, gp_exp1 = gp_exp, gp_normal1 = gp_normal; int i; struct rcu_torture *rp; - struct rcu_torture *rp1; struct rcu_torture *old_rp; static DEFINE_TORTURE_RANDOM(rand); + int synctype[] = { RTWS_DEF_FREE, RTWS_EXP_SYNC, RTWS_COND_GET }; + int nsynctypes = 0; VERBOSE_TOROUT_STRING("rcu_torture_writer task started"); set_user_nice(current, MAX_NICE); + /* Initialize synctype[] array. If none set, take default. */ + if (!gp_cond1 && !gp_exp1 && !gp_normal1) + gp_cond1 = gp_exp1 = gp_normal1 = true; + if (gp_cond1 && cur_ops->get_state && cur_ops->cond_sync) + synctype[nsynctypes++] = RTWS_COND_GET; + else if (gp_cond && (!cur_ops->get_state || !cur_ops->cond_sync)) + pr_alert("rcu_torture_writer: gp_cond without primitives.\n"); + if (gp_exp1 && cur_ops->exp_sync) + synctype[nsynctypes++] = RTWS_EXP_SYNC; + else if (gp_exp && !cur_ops->exp_sync) + pr_alert("rcu_torture_writer: gp_exp without primitives.\n"); + if (gp_normal1 && cur_ops->deferred_free) + synctype[nsynctypes++] = RTWS_DEF_FREE; + else if (gp_normal && !cur_ops->deferred_free) + pr_alert("rcu_torture_writer: gp_normal without primitives.\n"); + if (WARN_ONCE(nsynctypes == 0, + "rcu_torture_writer: No update-side primitives.\n")) { + rcu_torture_writer_state = RTWS_STOPPING; + torture_kthread_stopping("rcu_torture_writer"); + } + do { rcu_torture_writer_state = RTWS_FIXED_DELAY; schedule_timeout_uninterruptible(1); @@ -736,32 +798,30 @@ rcu_torture_writer(void *arg) i = RCU_TORTURE_PIPE_LEN; atomic_inc(&rcu_torture_wcount[i]); old_rp->rtort_pipe_count++; - if (gp_normal == gp_exp) - exp = !!(torture_random(&rand) & 0x80); - else - exp = gp_exp; - if (!exp) { + switch (synctype[torture_random(&rand) % nsynctypes]) { + case RTWS_DEF_FREE: rcu_torture_writer_state = RTWS_DEF_FREE; cur_ops->deferred_free(old_rp); - } else { + break; + case RTWS_EXP_SYNC: rcu_torture_writer_state = RTWS_EXP_SYNC; cur_ops->exp_sync(); - list_add(&old_rp->rtort_free, - &rcu_torture_removed); - list_for_each_entry_safe(rp, rp1, - &rcu_torture_removed, - rtort_free) { - i = rp->rtort_pipe_count; - if (i > RCU_TORTURE_PIPE_LEN) - i = RCU_TORTURE_PIPE_LEN; - atomic_inc(&rcu_torture_wcount[i]); - if (++rp->rtort_pipe_count >= - RCU_TORTURE_PIPE_LEN) { - rp->rtort_mbtest = 0; - list_del(&rp->rtort_free); - rcu_torture_free(rp); - } - } + rcu_torture_pipe_update(old_rp); + break; + case RTWS_COND_GET: + rcu_torture_writer_state = RTWS_COND_GET; + gp_snap = cur_ops->get_state(); + i = torture_random(&rand) % 16; + if (i != 0) + schedule_timeout_interruptible(i); + udelay(torture_random(&rand) % 1000); + rcu_torture_writer_state = RTWS_COND_SYNC; + cur_ops->cond_sync(gp_snap); + rcu_torture_pipe_update(old_rp); + break; + default: + WARN_ON_ONCE(1); + break; } } rcutorture_record_progress(++rcu_torture_current_version);