From 1c21f14ec48a2256fb03682b24dddd23eacdc96f Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 4 Mar 2009 13:51:13 +0100 Subject: lockdep: fix incorrect state name In the recent mark_lock_irq() rework a bug snuck in that would report the state of write locks causing irq inversion under a read lock as a read lock. Fix this by masking the read bit of the state when validating write dependencies. Reported-by: Andrew Morton Signed-off-by: Peter Zijlstra LKML-Reference: <1236172646.5330.7450.camel@laptop> Signed-off-by: Ingo Molnar --- kernel/lockdep.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'kernel/lockdep.c') diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 022d2ed7fd8b..ef6584fd9fe5 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -2015,7 +2015,8 @@ typedef int (*check_usage_f)(struct task_struct *, struct held_lock *, enum lock_usage_bit bit, const char *name); static int -mark_lock_irq(struct task_struct *curr, struct held_lock *this, int new_bit) +mark_lock_irq(struct task_struct *curr, struct held_lock *this, + enum lock_usage_bit new_bit) { int excl_bit = exclusive_bit(new_bit); int read = new_bit & 1; @@ -2043,7 +2044,7 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, int new_bit) * states. */ if ((!read || !dir || STRICT_READ_CHECKS) && - !usage(curr, this, excl_bit, state_name(new_bit))) + !usage(curr, this, excl_bit, state_name(new_bit & ~1))) return 0; /* -- cgit v1.2.3 From 26575e28df5eb2050c02369843faba38cecb4d8c Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 4 Mar 2009 14:53:24 +0100 Subject: lockdep: remove extra "irq" string Impact: clarify lockdep printk text print_irq_inversion_bug() gets handed state strings of the form "HARDIRQ", "SOFTIRQ", "RECLAIM_FS" and appends "-irq-{un,}safe" to them, which is either redudant for *IRQ or confusing in the RECLAIM_FS case. Signed-off-by: Peter Zijlstra LKML-Reference: <1236175192.5330.7585.camel@laptop> Signed-off-by: Ingo Molnar --- kernel/lockdep.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/lockdep.c') diff --git a/kernel/lockdep.c b/kernel/lockdep.c index ef6584fd9fe5..02014f7ccc86 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -1900,9 +1900,9 @@ print_irq_inversion_bug(struct task_struct *curr, struct lock_class *other, curr->comm, task_pid_nr(curr)); print_lock(this); if (forwards) - printk("but this lock took another, %s-irq-unsafe lock in the past:\n", irqclass); + printk("but this lock took another, %s-unsafe lock in the past:\n", irqclass); else - printk("but this lock was taken by another, %s-irq-safe lock in the past:\n", irqclass); + printk("but this lock was taken by another, %s-safe lock in the past:\n", irqclass); print_lock_name(other); printk("\n\nand interrupts could create inverse lock ordering between them.\n\n"); -- cgit v1.2.3 From efed792d6738964f399a508ef9e831cd60fa4657 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 4 Mar 2009 12:32:55 +0100 Subject: tracing: add lockdep tracepoints for lock acquire/release Augment the traces with lock names when lockdep is available: 1) | down_read_trylock() { 1) | _spin_lock_irqsave() { 1) | /* lock_acquire: &sem->wait_lock */ 1) 4.201 us | } 1) | _spin_unlock_irqrestore() { 1) | /* lock_release: &sem->wait_lock */ 1) 3.523 us | } 1) | /* lock_acquire: try read &mm->mmap_sem */ 1) + 13.386 us | } 1) 1.635 us | find_vma(); 1) | handle_mm_fault() { 1) | __do_fault() { 1) | filemap_fault() { 1) | find_lock_page() { 1) | find_get_page() { 1) | /* lock_acquire: read rcu_read_lock */ 1) | /* lock_release: rcu_read_lock */ 1) 5.697 us | } 1) 8.158 us | } 1) + 11.079 us | } 1) | _spin_lock() { 1) | /* lock_acquire: __pte_lockptr(page) */ 1) 3.949 us | } 1) 1.460 us | page_add_file_rmap(); 1) | _spin_unlock() { 1) | /* lock_release: __pte_lockptr(page) */ 1) 3.115 us | } 1) | unlock_page() { 1) 1.421 us | page_waitqueue(); 1) 1.220 us | __wake_up_bit(); 1) 6.519 us | } 1) + 34.328 us | } 1) + 37.452 us | } 1) | up_read() { 1) | /* lock_release: &mm->mmap_sem */ 1) | _spin_lock_irqsave() { 1) | /* lock_acquire: &sem->wait_lock */ 1) 3.865 us | } 1) | _spin_unlock_irqrestore() { 1) | /* lock_release: &sem->wait_lock */ 1) 8.562 us | } 1) + 17.370 us | } Signed-off-by: Peter Zijlstra Cc: Steven Rostedt Cc: =?ISO-8859-1?Q?T=F6r=F6k?= Edwin Cc: Jason Baron Cc: Frederic Weisbecker LKML-Reference: <1236166375.5330.7209.camel@laptop> Signed-off-by: Ingo Molnar --- include/trace/lockdep.h | 9 ++++++++ include/trace/lockdep_event_types.h | 44 +++++++++++++++++++++++++++++++++++++ include/trace/trace_event_types.h | 1 + include/trace/trace_events.h | 1 + kernel/lockdep.c | 17 ++++++++++++++ kernel/trace/trace.c | 14 +++++++----- kernel/trace/trace_events_stage_3.h | 4 ++-- 7 files changed, 82 insertions(+), 8 deletions(-) create mode 100644 include/trace/lockdep.h create mode 100644 include/trace/lockdep_event_types.h (limited to 'kernel/lockdep.c') diff --git a/include/trace/lockdep.h b/include/trace/lockdep.h new file mode 100644 index 000000000000..5ca67df87f2a --- /dev/null +++ b/include/trace/lockdep.h @@ -0,0 +1,9 @@ +#ifndef _TRACE_LOCKDEP_H +#define _TRACE_LOCKDEP_H + +#include +#include + +#include + +#endif diff --git a/include/trace/lockdep_event_types.h b/include/trace/lockdep_event_types.h new file mode 100644 index 000000000000..f713d74a82b4 --- /dev/null +++ b/include/trace/lockdep_event_types.h @@ -0,0 +1,44 @@ + +#ifndef TRACE_EVENT_FORMAT +# error Do not include this file directly. +# error Unless you know what you are doing. +#endif + +#undef TRACE_SYSTEM +#define TRACE_SYSTEM lock + +#ifdef CONFIG_LOCKDEP + +TRACE_FORMAT(lock_acquire, + TPPROTO(struct lockdep_map *lock, unsigned int subclass, + int trylock, int read, int check, + struct lockdep_map *next_lock, unsigned long ip), + TPARGS(lock, subclass, trylock, read, check, next_lock, ip), + TPFMT("%s%s%s", trylock ? "try " : "", + read ? "read " : "", lock->name) + ); + +TRACE_FORMAT(lock_release, + TPPROTO(struct lockdep_map *lock, int nested, unsigned long ip), + TPARGS(lock, nested, ip), + TPFMT("%s", lock->name) + ); + +#ifdef CONFIG_LOCK_STAT + +TRACE_FORMAT(lock_contended, + TPPROTO(struct lockdep_map *lock, unsigned long ip), + TPARGS(lock, ip), + TPFMT("%s", lock->name) + ); + +TRACE_FORMAT(lock_acquired, + TPPROTO(struct lockdep_map *lock, unsigned long ip), + TPARGS(lock, ip), + TPFMT("%s", lock->name) + ); + +#endif +#endif + +#undef TRACE_SYSTEM diff --git a/include/trace/trace_event_types.h b/include/trace/trace_event_types.h index 33c8ed5ccb6c..df56f5694be6 100644 --- a/include/trace/trace_event_types.h +++ b/include/trace/trace_event_types.h @@ -2,3 +2,4 @@ #include #include +#include diff --git a/include/trace/trace_events.h b/include/trace/trace_events.h index ea2ef2051762..fd13750ca4ba 100644 --- a/include/trace/trace_events.h +++ b/include/trace/trace_events.h @@ -2,3 +2,4 @@ #include #include +#include diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 02014f7ccc86..cb70c1db85d0 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -42,6 +42,7 @@ #include #include #include +#include #include @@ -2913,6 +2914,8 @@ void lock_set_class(struct lockdep_map *lock, const char *name, } EXPORT_SYMBOL_GPL(lock_set_class); +DEFINE_TRACE(lock_acquire); + /* * We are not always called with irqs disabled - do that here, * and also avoid lockdep recursion: @@ -2923,6 +2926,8 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass, { unsigned long flags; + trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip); + if (unlikely(current->lockdep_recursion)) return; @@ -2937,11 +2942,15 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass, } EXPORT_SYMBOL_GPL(lock_acquire); +DEFINE_TRACE(lock_release); + void lock_release(struct lockdep_map *lock, int nested, unsigned long ip) { unsigned long flags; + trace_lock_release(lock, nested, ip); + if (unlikely(current->lockdep_recursion)) return; @@ -3090,10 +3099,14 @@ found_it: lock->ip = ip; } +DEFINE_TRACE(lock_contended); + void lock_contended(struct lockdep_map *lock, unsigned long ip) { unsigned long flags; + trace_lock_contended(lock, ip); + if (unlikely(!lock_stat)) return; @@ -3109,10 +3122,14 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip) } EXPORT_SYMBOL_GPL(lock_contended); +DEFINE_TRACE(lock_acquired); + void lock_acquired(struct lockdep_map *lock, unsigned long ip) { unsigned long flags; + trace_lock_acquired(lock, ip); + if (unlikely(!lock_stat)) return; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 12539f72f4a5..c8abbb0c8397 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -623,7 +623,7 @@ static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; static int cmdline_idx; -static DEFINE_SPINLOCK(trace_cmdline_lock); +static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; /* temporary disable recording */ static atomic_t trace_record_cmdline_disabled __read_mostly; @@ -735,7 +735,7 @@ static void trace_save_cmdline(struct task_struct *tsk) * nor do we want to disable interrupts, * so if we miss here, then better luck next time. */ - if (!spin_trylock(&trace_cmdline_lock)) + if (!__raw_spin_trylock(&trace_cmdline_lock)) return; idx = map_pid_to_cmdline[tsk->pid]; @@ -753,7 +753,7 @@ static void trace_save_cmdline(struct task_struct *tsk) memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); - spin_unlock(&trace_cmdline_lock); + __raw_spin_unlock(&trace_cmdline_lock); } char *trace_find_cmdline(int pid) @@ -3751,7 +3751,7 @@ static __init int tracer_init_debugfs(void) int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) { - static DEFINE_SPINLOCK(trace_buf_lock); + static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; static char trace_buf[TRACE_BUF_SIZE]; struct ring_buffer_event *event; @@ -3773,7 +3773,8 @@ int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) goto out; pause_graph_tracing(); - spin_lock_irqsave(&trace_buf_lock, irq_flags); + raw_local_irq_save(irq_flags); + __raw_spin_lock(&trace_buf_lock); len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); len = min(len, TRACE_BUF_SIZE-1); @@ -3792,7 +3793,8 @@ int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) ring_buffer_unlock_commit(tr->buffer, event); out_unlock: - spin_unlock_irqrestore(&trace_buf_lock, irq_flags); + __raw_spin_unlock(&trace_buf_lock); + raw_local_irq_restore(irq_flags); unpause_graph_tracing(); out: preempt_enable_notrace(); diff --git a/kernel/trace/trace_events_stage_3.h b/kernel/trace/trace_events_stage_3.h index 041789ffbac1..2c8d76c7dbed 100644 --- a/kernel/trace/trace_events_stage_3.h +++ b/kernel/trace/trace_events_stage_3.h @@ -5,7 +5,7 @@ * * static void ftrace_event_(proto) * { - * event_trace_printk(_RET_IP_, "() " ); + * event_trace_printk(_RET_IP_, ": " ); * } * * static int ftrace_reg_event_(void) @@ -112,7 +112,7 @@ #define _TRACE_FORMAT(call, proto, args, fmt) \ static void ftrace_event_##call(proto) \ { \ - event_trace_printk(_RET_IP_, "(" #call ") " fmt); \ + event_trace_printk(_RET_IP_, #call ": " fmt); \ } \ \ static int ftrace_reg_event_##call(void) \ -- cgit v1.2.3 From 03d78913f01e8f6599823f00357ed17b32747d3d Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Thu, 5 Mar 2009 02:29:05 -0800 Subject: lockdep: remove duplicate CONFIG_DEBUG_LOCKDEP definitions Impact: cleanup The atomic debug modifiers are already defined in kernel/lockdep_internals.h. Signed-off-by: David Rientjes Acked-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/lockdep.c | 7 ------- 1 file changed, 7 deletions(-) (limited to 'kernel/lockdep.c') diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 02014f7ccc86..9a1e2bcc4b8d 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -433,13 +433,6 @@ atomic_t nr_find_usage_forwards_checks; atomic_t nr_find_usage_forwards_recursions; atomic_t nr_find_usage_backwards_checks; atomic_t nr_find_usage_backwards_recursions; -# define debug_atomic_inc(ptr) atomic_inc(ptr) -# define debug_atomic_dec(ptr) atomic_dec(ptr) -# define debug_atomic_read(ptr) atomic_read(ptr) -#else -# define debug_atomic_inc(ptr) do { } while (0) -# define debug_atomic_dec(ptr) do { } while (0) -# define debug_atomic_read(ptr) 0 #endif /* -- cgit v1.2.3