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Release 4.15 kernel/locking/lockdep_proc.c

Directory: kernel/locking
// SPDX-License-Identifier: GPL-2.0
/*
 * kernel/lockdep_proc.c
 *
 * Runtime locking correctness validator
 *
 * Started by Ingo Molnar:
 *
 *  Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
 *  Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
 *
 * Code for /proc/lockdep and /proc/lockdep_stats:
 *
 */
#include <linux/export.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/kallsyms.h>
#include <linux/debug_locks.h>
#include <linux/vmalloc.h>
#include <linux/sort.h>
#include <linux/uaccess.h>
#include <asm/div64.h>

#include "lockdep_internals.h"


static void *l_next(struct seq_file *m, void *v, loff_t *pos) { return seq_list_next(v, &all_lock_classes, pos); }

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PersonTokensPropCommitsCommitProp
Ingo Molnar2580.65%133.33%
Li Zefan516.13%133.33%
Tim Pepper13.23%133.33%
Total31100.00%3100.00%


static void *l_start(struct seq_file *m, loff_t *pos) { return seq_list_start_head(&all_lock_classes, *pos); }

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PersonTokensPropCommitsCommitProp
Ingo Molnar1661.54%133.33%
Tim Pepper623.08%133.33%
Li Zefan415.38%133.33%
Total26100.00%3100.00%


static void l_stop(struct seq_file *m, void *v) { }

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PersonTokensPropCommitsCommitProp
Ingo Molnar14100.00%1100.00%
Total14100.00%1100.00%


static void print_name(struct seq_file *m, struct lock_class *class) { char str[KSYM_NAME_LEN]; const char *name = class->name; if (!name) { name = __get_key_name(class->key, str); seq_printf(m, "%s", name); } else{ seq_printf(m, "%s", name); if (class->name_version > 1) seq_printf(m, "#%d", class->name_version); if (class->subclass) seq_printf(m, "/%d", class->subclass); } }

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PersonTokensPropCommitsCommitProp
Jason Baron10599.06%150.00%
Cyrill V. Gorcunov10.94%150.00%
Total106100.00%2100.00%


static int l_show(struct seq_file *m, void *v) { struct lock_class *class = list_entry(v, struct lock_class, lock_entry); struct lock_list *entry; char usage[LOCK_USAGE_CHARS]; if (v == &all_lock_classes) { seq_printf(m, "all lock classes:\n"); return 0; } seq_printf(m, "%p", class->key); #ifdef CONFIG_DEBUG_LOCKDEP seq_printf(m, " OPS:%8ld", class->ops); #endif #ifdef CONFIG_PROVE_LOCKING seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class)); seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class)); #endif get_usage_chars(class, usage); seq_printf(m, " %s", usage); seq_printf(m, ": "); print_name(m, class); seq_puts(m, "\n"); list_for_each_entry(entry, &class->locks_after, entry) { if (entry->distance == 1) { seq_printf(m, " -> [%p] ", entry->class->key); print_name(m, entry->class); seq_puts(m, "\n"); } } seq_puts(m, "\n"); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Ingo Molnar12458.49%112.50%
Jason Baron3918.40%112.50%
Tim Pepper188.49%112.50%
Stephen Hemminger115.19%112.50%
Li Zefan104.72%112.50%
Peter Zijlstra73.30%112.50%
Huang Ying20.94%112.50%
Nicholas Piggin10.47%112.50%
Total212100.00%8100.00%

static const struct seq_operations lockdep_ops = { .start = l_start, .next = l_next, .stop = l_stop, .show = l_show, };
static int lockdep_open(struct inode *inode, struct file *file) { return seq_open(file, &lockdep_ops); }

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PersonTokensPropCommitsCommitProp
Ingo Molnar2496.00%150.00%
Li Zefan14.00%150.00%
Total25100.00%2100.00%

static const struct file_operations proc_lockdep_operations = { .open = lockdep_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; #ifdef CONFIG_PROVE_LOCKING
static void *lc_start(struct seq_file *m, loff_t *pos) { if (*pos == 0) return SEQ_START_TOKEN; if (*pos - 1 < nr_lock_chains) return lock_chains + (*pos - 1); return NULL; }

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Huang Ying3266.67%133.33%
Li Zefan1633.33%266.67%
Total48100.00%3100.00%


static void *lc_next(struct seq_file *m, void *v, loff_t *pos) { (*pos)++; return lc_start(m, pos); }

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Huang Ying1955.88%133.33%
Li Zefan1544.12%266.67%
Total34100.00%3100.00%


static void lc_stop(struct seq_file *m, void *v) { }

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PersonTokensPropCommitsCommitProp
Huang Ying14100.00%1100.00%
Total14100.00%1100.00%


static int lc_show(struct seq_file *m, void *v) { struct lock_chain *chain = v; struct lock_class *class; int i; if (v == SEQ_START_TOKEN) { if (nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS) seq_printf(m, "(buggered) "); seq_printf(m, "all lock chains:\n"); return 0; } seq_printf(m, "irq_context: %d\n", chain->irq_context); for (i = 0; i < chain->depth; i++) { class = lock_chain_get_class(chain, i); if (!class->key) continue; seq_printf(m, "[%p] ", class->key); print_name(m, class); seq_puts(m, "\n"); } seq_puts(m, "\n"); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Huang Ying12085.11%133.33%
Peter Zijlstra139.22%133.33%
Rabin Vincent85.67%133.33%
Total141100.00%3100.00%

static const struct seq_operations lockdep_chains_ops = { .start = lc_start, .next = lc_next, .stop = lc_stop, .show = lc_show, };
static int lockdep_chains_open(struct inode *inode, struct file *file) { return seq_open(file, &lockdep_chains_ops); }

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PersonTokensPropCommitsCommitProp
Huang Ying2496.00%150.00%
Li Zefan14.00%150.00%
Total25100.00%2100.00%

static const struct file_operations proc_lockdep_chains_operations = { .open = lockdep_chains_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; #endif /* CONFIG_PROVE_LOCKING */
static void lockdep_stats_debug_show(struct seq_file *m) { #ifdef CONFIG_DEBUG_LOCKDEP unsigned long long hi1 = debug_atomic_read(hardirqs_on_events), hi2 = debug_atomic_read(hardirqs_off_events), hr1 = debug_atomic_read(redundant_hardirqs_on), hr2 = debug_atomic_read(redundant_hardirqs_off), si1 = debug_atomic_read(softirqs_on_events), si2 = debug_atomic_read(softirqs_off_events), sr1 = debug_atomic_read(redundant_softirqs_on), sr2 = debug_atomic_read(redundant_softirqs_off); seq_printf(m, " chain lookup misses: %11llu\n", debug_atomic_read(chain_lookup_misses)); seq_printf(m, " chain lookup hits: %11llu\n", debug_atomic_read(chain_lookup_hits)); seq_printf(m, " cyclic checks: %11llu\n", debug_atomic_read(nr_cyclic_checks)); seq_printf(m, " redundant checks: %11llu\n", debug_atomic_read(nr_redundant_checks)); seq_printf(m, " redundant links: %11llu\n", debug_atomic_read(nr_redundant)); seq_printf(m, " find-mask forwards checks: %11llu\n", debug_atomic_read(nr_find_usage_forwards_checks)); seq_printf(m, " find-mask backwards checks: %11llu\n", debug_atomic_read(nr_find_usage_backwards_checks)); seq_printf(m, " hardirq on events: %11llu\n", hi1); seq_printf(m, " hardirq off events: %11llu\n", hi2); seq_printf(m, " redundant hardirq ons: %11llu\n", hr1); seq_printf(m, " redundant hardirq offs: %11llu\n", hr2); seq_printf(m, " softirq on events: %11llu\n", si1); seq_printf(m, " softirq off events: %11llu\n", si2); seq_printf(m, " redundant softirq ons: %11llu\n", sr1); seq_printf(m, " redundant softirq offs: %11llu\n", sr2); #endif }

Contributors

PersonTokensPropCommitsCommitProp
Ingo Molnar19283.12%133.33%
Peter Zijlstra2410.39%133.33%
Frédéric Weisbecker156.49%133.33%
Total231100.00%3100.00%


static int lockdep_stats_show(struct seq_file *m, void *v) { struct lock_class *class; unsigned long nr_unused = 0, nr_uncategorized = 0, nr_irq_safe = 0, nr_irq_unsafe = 0, nr_softirq_safe = 0, nr_softirq_unsafe = 0, nr_hardirq_safe = 0, nr_hardirq_unsafe = 0, nr_irq_read_safe = 0, nr_irq_read_unsafe = 0, nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0, nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0, sum_forward_deps = 0; list_for_each_entry(class, &all_lock_classes, lock_entry) { if (class->usage_mask == 0) nr_unused++; if (class->usage_mask == LOCKF_USED) nr_uncategorized++; if (class->usage_mask & LOCKF_USED_IN_IRQ) nr_irq_safe++; if (class->usage_mask & LOCKF_ENABLED_IRQ) nr_irq_unsafe++; if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ) nr_softirq_safe++; if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ) nr_softirq_unsafe++; if (class->usage_mask & LOCKF_USED_IN_HARDIRQ) nr_hardirq_safe++; if (class->usage_mask & LOCKF_ENABLED_HARDIRQ) nr_hardirq_unsafe++; if (class->usage_mask & LOCKF_USED_IN_IRQ_READ) nr_irq_read_safe++; if (class->usage_mask & LOCKF_ENABLED_IRQ_READ) nr_irq_read_unsafe++; if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ) nr_softirq_read_safe++; if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ_READ) nr_softirq_read_unsafe++; if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ) nr_hardirq_read_safe++; if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ) nr_hardirq_read_unsafe++; #ifdef CONFIG_PROVE_LOCKING sum_forward_deps += lockdep_count_forward_deps(class); #endif } #ifdef CONFIG_DEBUG_LOCKDEP DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused); #endif seq_printf(m, " lock-classes: %11lu [max: %lu]\n", nr_lock_classes, MAX_LOCKDEP_KEYS); seq_printf(m, " direct dependencies: %11lu [max: %lu]\n", nr_list_entries, MAX_LOCKDEP_ENTRIES); seq_printf(m, " indirect dependencies: %11lu\n", sum_forward_deps); /* * Total number of dependencies: * * All irq-safe locks may nest inside irq-unsafe locks, * plus all the other known dependencies: */ seq_printf(m, " all direct dependencies: %11lu\n", nr_irq_unsafe * nr_irq_safe + nr_hardirq_unsafe * nr_hardirq_safe + nr_list_entries); #ifdef CONFIG_PROVE_LOCKING seq_printf(m, " dependency chains: %11lu [max: %lu]\n", nr_lock_chains, MAX_LOCKDEP_CHAINS); seq_printf(m, " dependency chain hlocks: %11d [max: %lu]\n", nr_chain_hlocks, MAX_LOCKDEP_CHAIN_HLOCKS); #endif #ifdef CONFIG_TRACE_IRQFLAGS seq_printf(m, " in-hardirq chains: %11u\n", nr_hardirq_chains); seq_printf(m, " in-softirq chains: %11u\n", nr_softirq_chains); #endif seq_printf(m, " in-process chains: %11u\n", nr_process_chains); seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n", nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES); seq_printf(m, " combined max dependencies: %11u\n", (nr_hardirq_chains + 1) * (nr_softirq_chains + 1) * (nr_process_chains + 1) ); seq_printf(m, " hardirq-safe locks: %11lu\n", nr_hardirq_safe); seq_printf(m, " hardirq-unsafe locks: %11lu\n", nr_hardirq_unsafe); seq_printf(m, " softirq-safe locks: %11lu\n", nr_softirq_safe); seq_printf(m, " softirq-unsafe locks: %11lu\n", nr_softirq_unsafe); seq_printf(m, " irq-safe locks: %11lu\n", nr_irq_safe); seq_printf(m, " irq-unsafe locks: %11lu\n", nr_irq_unsafe); seq_printf(m, " hardirq-read-safe locks: %11lu\n", nr_hardirq_read_safe); seq_printf(m, " hardirq-read-unsafe locks: %11lu\n", nr_hardirq_read_unsafe); seq_printf(m, " softirq-read-safe locks: %11lu\n", nr_softirq_read_safe); seq_printf(m, " softirq-read-unsafe locks: %11lu\n", nr_softirq_read_unsafe); seq_printf(m, " irq-read-safe locks: %11lu\n", nr_irq_read_safe); seq_printf(m, " irq-read-unsafe locks: %11lu\n", nr_irq_read_unsafe); seq_printf(m, " uncategorized locks: %11lu\n", nr_uncategorized); seq_printf(m, " unused locks: %11lu\n", nr_unused); seq_printf(m, " max locking depth: %11u\n", max_lockdep_depth); #ifdef CONFIG_PROVE_LOCKING seq_printf(m, " max bfs queue depth: %11u\n", max_bfs_queue_depth); #endif lockdep_stats_debug_show(m); seq_printf(m, " debug_locks: %11u\n", debug_locks); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Ingo Molnar54593.48%222.22%
Peter Zijlstra111.89%222.22%
Huang Ying111.89%111.11%
Lei Ming91.54%111.11%
Stephen Hemminger50.86%111.11%
David S. Miller10.17%111.11%
Robert P. J. Day10.17%111.11%
Total583100.00%9100.00%


static int lockdep_stats_open(struct inode *inode, struct file *file) { return single_open(file, lockdep_stats_show, NULL); }

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PersonTokensPropCommitsCommitProp
Ingo Molnar26100.00%1100.00%
Total26100.00%1100.00%

static const struct file_operations proc_lockdep_stats_operations = { .open = lockdep_stats_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; #ifdef CONFIG_LOCK_STAT struct lock_stat_data { struct lock_class *class; struct lock_class_stats stats; }; struct lock_stat_seq { struct lock_stat_data *iter_end; struct lock_stat_data stats[MAX_LOCKDEP_KEYS]; }; /* * sort on absolute number of contentions */
static int lock_stat_cmp(const void *l, const void *r) { const struct lock_stat_data *dl = l, *dr = r; unsigned long nl, nr; nl = dl->stats.read_waittime.nr + dl->stats.write_waittime.nr; nr = dr->stats.read_waittime.nr + dr->stats.write_waittime.nr; return nr - nl; }

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PersonTokensPropCommitsCommitProp
Peter Zijlstra6686.84%150.00%
Ingo Molnar1013.16%150.00%
Total76100.00%2100.00%


static void seq_line(struct seq_file *m, char c, int offset, int length) { int i; for (i = 0; i < offset; i++) seq_puts(m, " "); for (i = 0; i < length; i++) seq_printf(m, "%c", c); seq_puts(m, "\n"); }

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PersonTokensPropCommitsCommitProp
Peter Zijlstra6691.67%150.00%
Ingo Molnar68.33%150.00%
Total72100.00%2100.00%


static void snprint_time(char *buf, size_t bufsiz, s64 nr) { s64 div; s32 rem; nr += 5; /* for display rounding */ div = div_s64_rem(nr, 1000, &rem); snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10); }

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PersonTokensPropCommitsCommitProp
Peter Zijlstra5081.97%250.00%
Ingo Molnar69.84%125.00%
Joe Korty58.20%125.00%
Total61100.00%4100.00%


static void seq_time(struct seq_file *m, s64 time) { char num[15]; snprint_time(num, sizeof(num), time); seq_printf(m, " %14s", num); }

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PersonTokensPropCommitsCommitProp
Peter Zijlstra41100.00%1100.00%
Total41100.00%1100.00%


static void seq_lock_time(struct seq_file *m, struct lock_time *lt) { seq_printf(m, "%14lu", lt->nr); seq_time(m, lt->min); seq_time(m, lt->max); seq_time(m, lt->total); seq_time(m, lt->nr ? div_s64(lt->total, lt->nr) : 0); }

Contributors

PersonTokensPropCommitsCommitProp
Peter Zijlstra5369.74%250.00%
Davidlohr Bueso A2127.63%125.00%
Ingo Molnar22.63%125.00%
Total76100.00%4100.00%


static void seq_stats(struct seq_file *m, struct lock_stat_data *data) { struct lockdep_subclass_key *ckey; struct lock_class_stats *stats; struct lock_class *class; const char *cname; int i, namelen; char name[39]; class = data->class; stats = &data->stats; namelen = 38; if (class->name_version > 1) namelen -= 2; /* XXX truncates versions > 9 */ if (class->subclass) namelen -= 2; rcu_read_lock_sched(); cname = rcu_dereference_sched(class->name); ckey = rcu_dereference_sched(class->key); if (!cname && !ckey) { rcu_read_unlock_sched(); return; } else if (!cname) { char str[KSYM_NAME_LEN]; const char *key_name; key_name = __get_key_name(ckey, str); snprintf(name, namelen, "%s", key_name); } else { snprintf(name, namelen, "%s", cname); } rcu_read_unlock_sched(); namelen = strlen(name); if (class->name_version > 1) { snprintf(name+namelen, 3, "#%d", class->name_version); namelen += 2; } if (class->subclass) { snprintf(name+namelen, 3, "/%d", class->subclass); namelen += 2; } if (stats->write_holdtime.nr) { if (stats->read_holdtime.nr) seq_printf(m, "%38s-W:", name); else seq_printf(m, "%40s:", name); seq_printf(m, "%14lu ", stats->bounces[bounce_contended_write]); seq_lock_time(m, &stats->write_waittime); seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_write]); seq_lock_time(m, &stats->write_holdtime); seq_puts(m, "\n"); } if (stats->read_holdtime.nr) { seq_printf(m, "%38s-R:", name); seq_printf(m, "%14lu ", stats->bounces[bounce_contended_read]); seq_lock_time(m, &stats->read_waittime); seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_read]); seq_lock_time(m, &stats->read_holdtime); seq_puts(m, "\n"); } if (stats->read_waittime.nr + stats->write_waittime.nr == 0) return; if (stats->read_holdtime.nr) namelen += 2; for (i = 0; i < LOCKSTAT_POINTS; i++) { char ip[32]; if (class->contention_point[i] == 0) break; if (!i) seq_line(m, '-', 40-namelen, namelen); snprintf(ip, sizeof(ip), "[<%p>]", (void *)class->contention_point[i]); seq_printf(m, "%40s %14lu %29s %pS\n", name, stats->contention_point[i], ip, (void *)class->contention_point[i]); } for (i = 0; i < LOCKSTAT_POINTS; i++) { char ip[32]; if (class->contending_point[i] == 0) break; if (!i) seq_line(m, '-', 40-namelen, namelen); snprintf(ip, sizeof(ip), "[<%p>]", (void *)class->contending_point[i]); seq_printf(m, "%40s %14lu %29s %pS\n", name, stats->contending_point[i], ip, (void *)class->contending_point[i]); } if (i) { seq_puts(m, "\n"); seq_line(m, '.', 0, 40 + 1 + 12 * (14 + 1)); seq_puts(m, "\n"); } }

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PersonTokensPropCommitsCommitProp
Peter Zijlstra66096.63%571.43%
Joe Perches223.22%114.29%
Davidlohr Bueso A10.15%114.29%
Total683100.00%7100.00%


static void seq_header(struct seq_file *m) { seq_puts(m, "lock_stat version 0.4\n"); if (unlikely(!debug_locks)) seq_printf(m, "*WARNING* lock debugging disabled!! - possibly due to a lockdep warning\n"); seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1)); seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s %14s %14s " "%14s %14s\n", "class name", "con-bounces", "contentions", "waittime-min", "waittime-max", "waittime-total", "waittime-avg", "acq-bounces", "acquisitions", "holdtime-min", "holdtime-max", "holdtime-total", "holdtime-avg"); seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1)); seq_printf(m, "\n"); }

Contributors

PersonTokensPropCommitsCommitProp
Peter Zijlstra10792.24%375.00%
Davidlohr Bueso A97.76%125.00%
Total116100.00%4100.00%


static void *ls_start(struct seq_file *m, loff_t *pos) { struct lock_stat_seq *data = m->private; struct lock_stat_data *iter; if (*pos == 0) return SEQ_START_TOKEN; iter = data