From efc151c33b971148894789dc7c5589dec46d4348 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 18 Mar 2013 16:24:11 -0700 Subject: rcu: Convert rcutree_plugin.h printk calls This commit converts printk() calls to the corresponding pr_*() calls. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutree_plugin.h | 45 ++++++++++++++++++++++----------------------- 1 file changed, 22 insertions(+), 23 deletions(-) (limited to 'kernel/rcutree_plugin.h') diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 3db5a375d8dd..207844ea0226 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -53,38 +53,37 @@ static char __initdata nocb_buf[NR_CPUS * 5]; static void __init rcu_bootup_announce_oddness(void) { #ifdef CONFIG_RCU_TRACE - printk(KERN_INFO "\tRCU debugfs-based tracing is enabled.\n"); + pr_info("\tRCU debugfs-based tracing is enabled.\n"); #endif #if (defined(CONFIG_64BIT) && CONFIG_RCU_FANOUT != 64) || (!defined(CONFIG_64BIT) && CONFIG_RCU_FANOUT != 32) - printk(KERN_INFO "\tCONFIG_RCU_FANOUT set to non-default value of %d\n", + pr_info("\tCONFIG_RCU_FANOUT set to non-default value of %d\n", CONFIG_RCU_FANOUT); #endif #ifdef CONFIG_RCU_FANOUT_EXACT - printk(KERN_INFO "\tHierarchical RCU autobalancing is disabled.\n"); + pr_info("\tHierarchical RCU autobalancing is disabled.\n"); #endif #ifdef CONFIG_RCU_FAST_NO_HZ - printk(KERN_INFO - "\tRCU dyntick-idle grace-period acceleration is enabled.\n"); + pr_info("\tRCU dyntick-idle grace-period acceleration is enabled.\n"); #endif #ifdef CONFIG_PROVE_RCU - printk(KERN_INFO "\tRCU lockdep checking is enabled.\n"); + pr_info("\tRCU lockdep checking is enabled.\n"); #endif #ifdef CONFIG_RCU_TORTURE_TEST_RUNNABLE - printk(KERN_INFO "\tRCU torture testing starts during boot.\n"); + pr_info("\tRCU torture testing starts during boot.\n"); #endif #if defined(CONFIG_TREE_PREEMPT_RCU) && !defined(CONFIG_RCU_CPU_STALL_VERBOSE) - printk(KERN_INFO "\tDump stacks of tasks blocking RCU-preempt GP.\n"); + pr_info("\tDump stacks of tasks blocking RCU-preempt GP.\n"); #endif #if defined(CONFIG_RCU_CPU_STALL_INFO) - printk(KERN_INFO "\tAdditional per-CPU info printed with stalls.\n"); + pr_info("\tAdditional per-CPU info printed with stalls.\n"); #endif #if NUM_RCU_LVL_4 != 0 - printk(KERN_INFO "\tFour-level hierarchy is enabled.\n"); + pr_info("\tFour-level hierarchy is enabled.\n"); #endif if (rcu_fanout_leaf != CONFIG_RCU_FANOUT_LEAF) - printk(KERN_INFO "\tExperimental boot-time adjustment of leaf fanout to %d.\n", rcu_fanout_leaf); + pr_info("\tExperimental boot-time adjustment of leaf fanout to %d.\n", rcu_fanout_leaf); if (nr_cpu_ids != NR_CPUS) - printk(KERN_INFO "\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%d.\n", NR_CPUS, nr_cpu_ids); + pr_info("\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%d.\n", NR_CPUS, nr_cpu_ids); #ifdef CONFIG_RCU_NOCB_CPU #ifndef CONFIG_RCU_NOCB_CPU_NONE if (!have_rcu_nocb_mask) { @@ -123,7 +122,7 @@ static int rcu_preempted_readers_exp(struct rcu_node *rnp); */ static void __init rcu_bootup_announce(void) { - printk(KERN_INFO "Preemptible hierarchical RCU implementation.\n"); + pr_info("Preemptible hierarchical RCU implementation.\n"); rcu_bootup_announce_oddness(); } @@ -490,13 +489,13 @@ static void rcu_print_detail_task_stall(struct rcu_state *rsp) static void rcu_print_task_stall_begin(struct rcu_node *rnp) { - printk(KERN_ERR "\tTasks blocked on level-%d rcu_node (CPUs %d-%d):", + pr_err("\tTasks blocked on level-%d rcu_node (CPUs %d-%d):", rnp->level, rnp->grplo, rnp->grphi); } static void rcu_print_task_stall_end(void) { - printk(KERN_CONT "\n"); + pr_cont("\n"); } #else /* #ifdef CONFIG_RCU_CPU_STALL_INFO */ @@ -526,7 +525,7 @@ static int rcu_print_task_stall(struct rcu_node *rnp) t = list_entry(rnp->gp_tasks, struct task_struct, rcu_node_entry); list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry) { - printk(KERN_CONT " P%d", t->pid); + pr_cont(" P%d", t->pid); ndetected++; } rcu_print_task_stall_end(); @@ -942,7 +941,7 @@ static struct rcu_state *rcu_state = &rcu_sched_state; */ static void __init rcu_bootup_announce(void) { - printk(KERN_INFO "Hierarchical RCU implementation.\n"); + pr_info("Hierarchical RCU implementation.\n"); rcu_bootup_announce_oddness(); } @@ -1883,7 +1882,7 @@ static void print_cpu_stall_fast_no_hz(char *cp, int cpu) /* Initiate the stall-info list. */ static void print_cpu_stall_info_begin(void) { - printk(KERN_CONT "\n"); + pr_cont("\n"); } /* @@ -1914,7 +1913,7 @@ static void print_cpu_stall_info(struct rcu_state *rsp, int cpu) ticks_value = rsp->gpnum - rdp->gpnum; } print_cpu_stall_fast_no_hz(fast_no_hz, cpu); - printk(KERN_ERR "\t%d: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u %s\n", + pr_err("\t%d: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u %s\n", cpu, ticks_value, ticks_title, atomic_read(&rdtp->dynticks) & 0xfff, rdtp->dynticks_nesting, rdtp->dynticks_nmi_nesting, @@ -1925,7 +1924,7 @@ static void print_cpu_stall_info(struct rcu_state *rsp, int cpu) /* Terminate the stall-info list. */ static void print_cpu_stall_info_end(void) { - printk(KERN_ERR "\t"); + pr_err("\t"); } /* Zero ->ticks_this_gp for all flavors of RCU. */ @@ -1948,17 +1947,17 @@ static void increment_cpu_stall_ticks(void) static void print_cpu_stall_info_begin(void) { - printk(KERN_CONT " {"); + pr_cont(" {"); } static void print_cpu_stall_info(struct rcu_state *rsp, int cpu) { - printk(KERN_CONT " %d", cpu); + pr_cont(" %d", cpu); } static void print_cpu_stall_info_end(void) { - printk(KERN_CONT "} "); + pr_cont("} "); } static void zero_cpu_stall_ticks(struct rcu_data *rdp) -- cgit v1.2.3 From 470716fc043aba2fea832334e58d5cd5d82288a3 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 19 Mar 2013 11:32:11 -0700 Subject: rcu: Switch callers from rcu_process_gp_end() to note_gp_changes() Because note_gp_changes() now incorporates rcu_process_gp_end() function, this commit switches to the former and eliminates the latter. In addition, this commit changes external calls from __rcu_process_gp_end() to __note_gp_changes(). Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutree_plugin.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/rcutree_plugin.h') diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 207844ea0226..f279148a0168 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -1628,7 +1628,7 @@ static bool rcu_try_advance_all_cbs(void) */ if (rdp->completed != rnp->completed && rdp->nxttail[RCU_DONE_TAIL] != rdp->nxttail[RCU_NEXT_TAIL]) - rcu_process_gp_end(rsp, rdp); + note_gp_changes(rsp, rdp); if (cpu_has_callbacks_ready_to_invoke(rdp)) cbs_ready = true; -- cgit v1.2.3 From 9a5739d73f9369ba1cdba3889ee4e2f87be25a46 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 28 Mar 2013 20:48:36 -0700 Subject: rcu: Remove "Experimental" flags After a release or two, features are no longer experimental. Therefore, this commit removes the "Experimental" tag from them. Reported-by: Paul Gortmaker Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutree_plugin.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'kernel/rcutree_plugin.h') diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 207844ea0226..6b3ccaae93ab 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -81,7 +81,7 @@ static void __init rcu_bootup_announce_oddness(void) pr_info("\tFour-level hierarchy is enabled.\n"); #endif if (rcu_fanout_leaf != CONFIG_RCU_FANOUT_LEAF) - pr_info("\tExperimental boot-time adjustment of leaf fanout to %d.\n", rcu_fanout_leaf); + pr_info("\tBoot-time adjustment of leaf fanout to %d.\n", rcu_fanout_leaf); if (nr_cpu_ids != NR_CPUS) pr_info("\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%d.\n", NR_CPUS, nr_cpu_ids); #ifdef CONFIG_RCU_NOCB_CPU @@ -91,19 +91,19 @@ static void __init rcu_bootup_announce_oddness(void) have_rcu_nocb_mask = true; } #ifdef CONFIG_RCU_NOCB_CPU_ZERO - pr_info("\tExperimental no-CBs CPU 0\n"); + pr_info("\tOffload RCU callbacks from CPU 0\n"); cpumask_set_cpu(0, rcu_nocb_mask); #endif /* #ifdef CONFIG_RCU_NOCB_CPU_ZERO */ #ifdef CONFIG_RCU_NOCB_CPU_ALL - pr_info("\tExperimental no-CBs for all CPUs\n"); + pr_info("\tOffload RCU callbacks from all CPUs\n"); cpumask_setall(rcu_nocb_mask); #endif /* #ifdef CONFIG_RCU_NOCB_CPU_ALL */ #endif /* #ifndef CONFIG_RCU_NOCB_CPU_NONE */ if (have_rcu_nocb_mask) { cpulist_scnprintf(nocb_buf, sizeof(nocb_buf), rcu_nocb_mask); - pr_info("\tExperimental no-CBs CPUs: %s.\n", nocb_buf); + pr_info("\tOffload RCU callbacks from CPUs: %s.\n", nocb_buf); if (rcu_nocb_poll) - pr_info("\tExperimental polled no-CBs CPUs.\n"); + pr_info("\tPoll for callbacks from no-CBs CPUs.\n"); } #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ } -- cgit v1.2.3 From 2439b696cb5303f1eeb6aeebcee19e0056c3dd6e Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 11 Apr 2013 10:15:52 -0700 Subject: rcu: Shrink TINY_RCU by moving exit_rcu() Now that TINY_PREEMPT_RCU is no more, exit_rcu() is always an empty function. But if TINY_RCU is going to have an empty function, it should be in include/linux/rcutiny.h, where it does not bloat the kernel. This commit therefore moves exit_rcu() out of kernel/rcupdate.c to kernel/rcutree_plugin.h, and places a static inline empty function in include/linux/rcutiny.h in order to shrink TINY_RCU a bit. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutree_plugin.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'kernel/rcutree_plugin.h') diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 207844ea0226..de701bbdb624 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -932,6 +932,24 @@ static void __init __rcu_init_preempt(void) rcu_init_one(&rcu_preempt_state, &rcu_preempt_data); } +/* + * Check for a task exiting while in a preemptible-RCU read-side + * critical section, clean up if so. No need to issue warnings, + * as debug_check_no_locks_held() already does this if lockdep + * is enabled. + */ +void exit_rcu(void) +{ + struct task_struct *t = current; + + if (likely(list_empty(¤t->rcu_node_entry))) + return; + t->rcu_read_lock_nesting = 1; + barrier(); + t->rcu_read_unlock_special = RCU_READ_UNLOCK_BLOCKED; + __rcu_read_unlock(); +} + #else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ static struct rcu_state *rcu_state = &rcu_sched_state; @@ -1100,6 +1118,14 @@ static void __init __rcu_init_preempt(void) { } +/* + * Because preemptible RCU does not exist, tasks cannot possibly exit + * while in preemptible RCU read-side critical sections. + */ +void exit_rcu(void) +{ +} + #endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ #ifdef CONFIG_RCU_BOOST -- cgit v1.2.3 From 49fb4c6290c70c418a5c25eee996d6b55ea132d6 Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Wed, 19 Jun 2013 14:52:21 -0400 Subject: rcu: delete __cpuinit usage from all rcu files The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. This removes all the drivers/rcu uses of the __cpuinit macros from all C files. [1] https://lkml.org/lkml/2013/5/20/589 Cc: "Paul E. McKenney" Cc: Josh Triplett Cc: Dipankar Sarma Reviewed-by: Josh Triplett Signed-off-by: Paul Gortmaker --- kernel/rcutree_plugin.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'kernel/rcutree_plugin.h') diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 63098a59216e..769e12e3151b 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -1352,7 +1352,7 @@ static void rcu_preempt_boost_start_gp(struct rcu_node *rnp) * already exist. We only create this kthread for preemptible RCU. * Returns zero if all is well, a negated errno otherwise. */ -static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp, +static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp, struct rcu_node *rnp) { int rnp_index = rnp - &rsp->node[0]; @@ -1507,7 +1507,7 @@ static int __init rcu_spawn_kthreads(void) } early_initcall(rcu_spawn_kthreads); -static void __cpuinit rcu_prepare_kthreads(int cpu) +static void rcu_prepare_kthreads(int cpu) { struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu); struct rcu_node *rnp = rdp->mynode; @@ -1549,7 +1549,7 @@ static int __init rcu_scheduler_really_started(void) } early_initcall(rcu_scheduler_really_started); -static void __cpuinit rcu_prepare_kthreads(int cpu) +static void rcu_prepare_kthreads(int cpu) { } -- cgit v1.2.3