| /* |
| * Read-Copy Update tracing for classic implementation |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| * |
| * Copyright IBM Corporation, 2008 |
| * |
| * Papers: http://www.rdrop.com/users/paulmck/RCU |
| * |
| * For detailed explanation of Read-Copy Update mechanism see - |
| * Documentation/RCU |
| * |
| */ |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/spinlock.h> |
| #include <linux/smp.h> |
| #include <linux/rcupdate.h> |
| #include <linux/interrupt.h> |
| #include <linux/sched.h> |
| #include <linux/atomic.h> |
| #include <linux/bitops.h> |
| #include <linux/module.h> |
| #include <linux/completion.h> |
| #include <linux/moduleparam.h> |
| #include <linux/percpu.h> |
| #include <linux/notifier.h> |
| #include <linux/cpu.h> |
| #include <linux/mutex.h> |
| #include <linux/debugfs.h> |
| #include <linux/seq_file.h> |
| |
| #define RCU_TREE_NONCORE |
| #include "rcutree.h" |
| |
| #ifdef CONFIG_RCU_BOOST |
| |
| static char convert_kthread_status(unsigned int kthread_status) |
| { |
| if (kthread_status > RCU_KTHREAD_MAX) |
| return '?'; |
| return "SRWOY"[kthread_status]; |
| } |
| |
| #endif /* #ifdef CONFIG_RCU_BOOST */ |
| |
| static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp) |
| { |
| if (!rdp->beenonline) |
| return; |
| seq_printf(m, "%3d%cc=%lu g=%lu pq=%d pgp=%lu qp=%d", |
| rdp->cpu, |
| cpu_is_offline(rdp->cpu) ? '!' : ' ', |
| rdp->completed, rdp->gpnum, |
| rdp->passed_quiesce, rdp->passed_quiesce_gpnum, |
| rdp->qs_pending); |
| seq_printf(m, " dt=%d/%llx/%d df=%lu", |
| atomic_read(&rdp->dynticks->dynticks), |
| rdp->dynticks->dynticks_nesting, |
| rdp->dynticks->dynticks_nmi_nesting, |
| rdp->dynticks_fqs); |
| seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi); |
| seq_printf(m, " ql=%ld qs=%c%c%c%c", |
| rdp->qlen, |
| ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] != |
| rdp->nxttail[RCU_NEXT_TAIL]], |
| ".R"[rdp->nxttail[RCU_WAIT_TAIL] != |
| rdp->nxttail[RCU_NEXT_READY_TAIL]], |
| ".W"[rdp->nxttail[RCU_DONE_TAIL] != |
| rdp->nxttail[RCU_WAIT_TAIL]], |
| ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]); |
| #ifdef CONFIG_RCU_BOOST |
| seq_printf(m, " kt=%d/%c/%d ktl=%x", |
| per_cpu(rcu_cpu_has_work, rdp->cpu), |
| convert_kthread_status(per_cpu(rcu_cpu_kthread_status, |
| rdp->cpu)), |
| per_cpu(rcu_cpu_kthread_cpu, rdp->cpu), |
| per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff); |
| #endif /* #ifdef CONFIG_RCU_BOOST */ |
| seq_printf(m, " b=%ld", rdp->blimit); |
| seq_printf(m, " ci=%lu co=%lu ca=%lu\n", |
| rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted); |
| } |
| |
| #define PRINT_RCU_DATA(name, func, m) \ |
| do { \ |
| int _p_r_d_i; \ |
| \ |
| for_each_possible_cpu(_p_r_d_i) \ |
| func(m, &per_cpu(name, _p_r_d_i)); \ |
| } while (0) |
| |
| static int show_rcudata(struct seq_file *m, void *unused) |
| { |
| #ifdef CONFIG_TREE_PREEMPT_RCU |
| seq_puts(m, "rcu_preempt:\n"); |
| PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data, m); |
| #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ |
| seq_puts(m, "rcu_sched:\n"); |
| PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data, m); |
| seq_puts(m, "rcu_bh:\n"); |
| PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data, m); |
| return 0; |
| } |
| |
| static int rcudata_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, show_rcudata, NULL); |
| } |
| |
| static const struct file_operations rcudata_fops = { |
| .owner = THIS_MODULE, |
| .open = rcudata_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp) |
| { |
| if (!rdp->beenonline) |
| return; |
| seq_printf(m, "%d,%s,%lu,%lu,%d,%lu,%d", |
| rdp->cpu, |
| cpu_is_offline(rdp->cpu) ? "\"N\"" : "\"Y\"", |
| rdp->completed, rdp->gpnum, |
| rdp->passed_quiesce, rdp->passed_quiesce_gpnum, |
| rdp->qs_pending); |
| seq_printf(m, ",%d,%llx,%d,%lu", |
| atomic_read(&rdp->dynticks->dynticks), |
| rdp->dynticks->dynticks_nesting, |
| rdp->dynticks->dynticks_nmi_nesting, |
| rdp->dynticks_fqs); |
| seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi); |
| seq_printf(m, ",%ld,\"%c%c%c%c\"", rdp->qlen, |
| ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] != |
| rdp->nxttail[RCU_NEXT_TAIL]], |
| ".R"[rdp->nxttail[RCU_WAIT_TAIL] != |
| rdp->nxttail[RCU_NEXT_READY_TAIL]], |
| ".W"[rdp->nxttail[RCU_DONE_TAIL] != |
| rdp->nxttail[RCU_WAIT_TAIL]], |
| ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]); |
| #ifdef CONFIG_RCU_BOOST |
| seq_printf(m, ",%d,\"%c\"", |
| per_cpu(rcu_cpu_has_work, rdp->cpu), |
| convert_kthread_status(per_cpu(rcu_cpu_kthread_status, |
| rdp->cpu))); |
| #endif /* #ifdef CONFIG_RCU_BOOST */ |
| seq_printf(m, ",%ld", rdp->blimit); |
| seq_printf(m, ",%lu,%lu,%lu\n", |
| rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted); |
| } |
| |
| static int show_rcudata_csv(struct seq_file *m, void *unused) |
| { |
| seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pgp\",\"pq\","); |
| seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\","); |
| seq_puts(m, "\"of\",\"ri\",\"ql\",\"qs\""); |
| #ifdef CONFIG_RCU_BOOST |
| seq_puts(m, "\"kt\",\"ktl\""); |
| #endif /* #ifdef CONFIG_RCU_BOOST */ |
| seq_puts(m, ",\"b\",\"ci\",\"co\",\"ca\"\n"); |
| #ifdef CONFIG_TREE_PREEMPT_RCU |
| seq_puts(m, "\"rcu_preempt:\"\n"); |
| PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data_csv, m); |
| #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ |
| seq_puts(m, "\"rcu_sched:\"\n"); |
| PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data_csv, m); |
| seq_puts(m, "\"rcu_bh:\"\n"); |
| PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data_csv, m); |
| return 0; |
| } |
| |
| static int rcudata_csv_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, show_rcudata_csv, NULL); |
| } |
| |
| static const struct file_operations rcudata_csv_fops = { |
| .owner = THIS_MODULE, |
| .open = rcudata_csv_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| #ifdef CONFIG_RCU_BOOST |
| |
| static void print_one_rcu_node_boost(struct seq_file *m, struct rcu_node *rnp) |
| { |
| seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu " |
| "j=%04x bt=%04x\n", |
| rnp->grplo, rnp->grphi, |
| "T."[list_empty(&rnp->blkd_tasks)], |
| "N."[!rnp->gp_tasks], |
| "E."[!rnp->exp_tasks], |
| "B."[!rnp->boost_tasks], |
| convert_kthread_status(rnp->boost_kthread_status), |
| rnp->n_tasks_boosted, rnp->n_exp_boosts, |
| rnp->n_normal_boosts, |
| (int)(jiffies & 0xffff), |
| (int)(rnp->boost_time & 0xffff)); |
| seq_printf(m, "%s: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n", |
| " balk", |
| rnp->n_balk_blkd_tasks, |
| rnp->n_balk_exp_gp_tasks, |
| rnp->n_balk_boost_tasks, |
| rnp->n_balk_notblocked, |
| rnp->n_balk_notyet, |
| rnp->n_balk_nos); |
| } |
| |
| static int show_rcu_node_boost(struct seq_file *m, void *unused) |
| { |
| struct rcu_node *rnp; |
| |
| rcu_for_each_leaf_node(&rcu_preempt_state, rnp) |
| print_one_rcu_node_boost(m, rnp); |
| return 0; |
| } |
| |
| static int rcu_node_boost_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, show_rcu_node_boost, NULL); |
| } |
| |
| static const struct file_operations rcu_node_boost_fops = { |
| .owner = THIS_MODULE, |
| .open = rcu_node_boost_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| /* |
| * Create the rcuboost debugfs entry. Standard error return. |
| */ |
| static int rcu_boost_trace_create_file(struct dentry *rcudir) |
| { |
| return !debugfs_create_file("rcuboost", 0444, rcudir, NULL, |
| &rcu_node_boost_fops); |
| } |
| |
| #else /* #ifdef CONFIG_RCU_BOOST */ |
| |
| static int rcu_boost_trace_create_file(struct dentry *rcudir) |
| { |
| return 0; /* There cannot be an error if we didn't create it! */ |
| } |
| |
| #endif /* #else #ifdef CONFIG_RCU_BOOST */ |
| |
| static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp) |
| { |
| unsigned long gpnum; |
| int level = 0; |
| struct rcu_node *rnp; |
| |
| gpnum = rsp->gpnum; |
| seq_printf(m, "c=%lu g=%lu s=%d jfq=%ld j=%x " |
| "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu\n", |
| rsp->completed, gpnum, rsp->fqs_state, |
| (long)(rsp->jiffies_force_qs - jiffies), |
| (int)(jiffies & 0xffff), |
| rsp->n_force_qs, rsp->n_force_qs_ngp, |
| rsp->n_force_qs - rsp->n_force_qs_ngp, |
| rsp->n_force_qs_lh); |
| for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < NUM_RCU_NODES; rnp++) { |
| if (rnp->level != level) { |
| seq_puts(m, "\n"); |
| level = rnp->level; |
| } |
| seq_printf(m, "%lx/%lx %c%c>%c %d:%d ^%d ", |
| rnp->qsmask, rnp->qsmaskinit, |
| ".G"[rnp->gp_tasks != NULL], |
| ".E"[rnp->exp_tasks != NULL], |
| ".T"[!list_empty(&rnp->blkd_tasks)], |
| rnp->grplo, rnp->grphi, rnp->grpnum); |
| } |
| seq_puts(m, "\n"); |
| } |
| |
| static int show_rcuhier(struct seq_file *m, void *unused) |
| { |
| #ifdef CONFIG_TREE_PREEMPT_RCU |
| seq_puts(m, "rcu_preempt:\n"); |
| print_one_rcu_state(m, &rcu_preempt_state); |
| #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ |
| seq_puts(m, "rcu_sched:\n"); |
| print_one_rcu_state(m, &rcu_sched_state); |
| seq_puts(m, "rcu_bh:\n"); |
| print_one_rcu_state(m, &rcu_bh_state); |
| return 0; |
| } |
| |
| static int rcuhier_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, show_rcuhier, NULL); |
| } |
| |
| static const struct file_operations rcuhier_fops = { |
| .owner = THIS_MODULE, |
| .open = rcuhier_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static void show_one_rcugp(struct seq_file *m, struct rcu_state *rsp) |
| { |
| unsigned long flags; |
| unsigned long completed; |
| unsigned long gpnum; |
| unsigned long gpage; |
| unsigned long gpmax; |
| struct rcu_node *rnp = &rsp->node[0]; |
| |
| raw_spin_lock_irqsave(&rnp->lock, flags); |
| completed = rsp->completed; |
| gpnum = rsp->gpnum; |
| if (rsp->completed == rsp->gpnum) |
| gpage = 0; |
| else |
| gpage = jiffies - rsp->gp_start; |
| gpmax = rsp->gp_max; |
| raw_spin_unlock_irqrestore(&rnp->lock, flags); |
| seq_printf(m, "%s: completed=%ld gpnum=%lu age=%ld max=%ld\n", |
| rsp->name, completed, gpnum, gpage, gpmax); |
| } |
| |
| static int show_rcugp(struct seq_file *m, void *unused) |
| { |
| #ifdef CONFIG_TREE_PREEMPT_RCU |
| show_one_rcugp(m, &rcu_preempt_state); |
| #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ |
| show_one_rcugp(m, &rcu_sched_state); |
| show_one_rcugp(m, &rcu_bh_state); |
| return 0; |
| } |
| |
| static int rcugp_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, show_rcugp, NULL); |
| } |
| |
| static const struct file_operations rcugp_fops = { |
| .owner = THIS_MODULE, |
| .open = rcugp_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp) |
| { |
| seq_printf(m, "%3d%cnp=%ld " |
| "qsp=%ld rpq=%ld cbr=%ld cng=%ld " |
| "gpc=%ld gps=%ld nf=%ld nn=%ld\n", |
| rdp->cpu, |
| cpu_is_offline(rdp->cpu) ? '!' : ' ', |
| rdp->n_rcu_pending, |
| rdp->n_rp_qs_pending, |
| rdp->n_rp_report_qs, |
| rdp->n_rp_cb_ready, |
| rdp->n_rp_cpu_needs_gp, |
| rdp->n_rp_gp_completed, |
| rdp->n_rp_gp_started, |
| rdp->n_rp_need_fqs, |
| rdp->n_rp_need_nothing); |
| } |
| |
| static void print_rcu_pendings(struct seq_file *m, struct rcu_state *rsp) |
| { |
| int cpu; |
| struct rcu_data *rdp; |
| |
| for_each_possible_cpu(cpu) { |
| rdp = per_cpu_ptr(rsp->rda, cpu); |
| if (rdp->beenonline) |
| print_one_rcu_pending(m, rdp); |
| } |
| } |
| |
| static int show_rcu_pending(struct seq_file *m, void *unused) |
| { |
| #ifdef CONFIG_TREE_PREEMPT_RCU |
| seq_puts(m, "rcu_preempt:\n"); |
| print_rcu_pendings(m, &rcu_preempt_state); |
| #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ |
| seq_puts(m, "rcu_sched:\n"); |
| print_rcu_pendings(m, &rcu_sched_state); |
| seq_puts(m, "rcu_bh:\n"); |
| print_rcu_pendings(m, &rcu_bh_state); |
| return 0; |
| } |
| |
| static int rcu_pending_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, show_rcu_pending, NULL); |
| } |
| |
| static const struct file_operations rcu_pending_fops = { |
| .owner = THIS_MODULE, |
| .open = rcu_pending_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static int show_rcutorture(struct seq_file *m, void *unused) |
| { |
| seq_printf(m, "rcutorture test sequence: %lu %s\n", |
| rcutorture_testseq >> 1, |
| (rcutorture_testseq & 0x1) ? "(test in progress)" : ""); |
| seq_printf(m, "rcutorture update version number: %lu\n", |
| rcutorture_vernum); |
| return 0; |
| } |
| |
| static int rcutorture_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, show_rcutorture, NULL); |
| } |
| |
| static const struct file_operations rcutorture_fops = { |
| .owner = THIS_MODULE, |
| .open = rcutorture_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static struct dentry *rcudir; |
| |
| static int __init rcutree_trace_init(void) |
| { |
| struct dentry *retval; |
| |
| rcudir = debugfs_create_dir("rcu", NULL); |
| if (!rcudir) |
| goto free_out; |
| |
| retval = debugfs_create_file("rcudata", 0444, rcudir, |
| NULL, &rcudata_fops); |
| if (!retval) |
| goto free_out; |
| |
| retval = debugfs_create_file("rcudata.csv", 0444, rcudir, |
| NULL, &rcudata_csv_fops); |
| if (!retval) |
| goto free_out; |
| |
| if (rcu_boost_trace_create_file(rcudir)) |
| goto free_out; |
| |
| retval = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops); |
| if (!retval) |
| goto free_out; |
| |
| retval = debugfs_create_file("rcuhier", 0444, rcudir, |
| NULL, &rcuhier_fops); |
| if (!retval) |
| goto free_out; |
| |
| retval = debugfs_create_file("rcu_pending", 0444, rcudir, |
| NULL, &rcu_pending_fops); |
| if (!retval) |
| goto free_out; |
| |
| retval = debugfs_create_file("rcutorture", 0444, rcudir, |
| NULL, &rcutorture_fops); |
| if (!retval) |
| goto free_out; |
| return 0; |
| free_out: |
| debugfs_remove_recursive(rcudir); |
| return 1; |
| } |
| |
| static void __exit rcutree_trace_cleanup(void) |
| { |
| debugfs_remove_recursive(rcudir); |
| } |
| |
| |
| module_init(rcutree_trace_init); |
| module_exit(rcutree_trace_cleanup); |
| |
| MODULE_AUTHOR("Paul E. McKenney"); |
| MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation"); |
| MODULE_LICENSE("GPL"); |