diff options
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 269 |
1 files changed, 222 insertions, 47 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 5b8db27fb6ef..465989585135 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -51,6 +51,7 @@ #include <linux/workqueue.h> #include <linux/sort.h> #include <linux/io.h> /* vmap_page_range() */ +#include <linux/fs_context.h> #include <asm/setup.h> /* COMMAND_LINE_SIZE */ @@ -120,6 +121,7 @@ static int tracing_disabled = 1; cpumask_var_t __read_mostly tracing_buffer_mask; +#define MAX_TRACER_SIZE 100 /* * ftrace_dump_on_oops - variable to dump ftrace buffer on oops * @@ -142,7 +144,40 @@ cpumask_var_t __read_mostly tracing_buffer_mask; char ftrace_dump_on_oops[MAX_TRACER_SIZE] = "0"; /* When set, tracing will stop when a WARN*() is hit */ -int __disable_trace_on_warning; +static int __disable_trace_on_warning; + +int tracepoint_printk_sysctl(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos); +static const struct ctl_table trace_sysctl_table[] = { + { + .procname = "ftrace_dump_on_oops", + .data = &ftrace_dump_on_oops, + .maxlen = MAX_TRACER_SIZE, + .mode = 0644, + .proc_handler = proc_dostring, + }, + { + .procname = "traceoff_on_warning", + .data = &__disable_trace_on_warning, + .maxlen = sizeof(__disable_trace_on_warning), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { + .procname = "tracepoint_printk", + .data = &tracepoint_printk, + .maxlen = sizeof(tracepoint_printk), + .mode = 0644, + .proc_handler = tracepoint_printk_sysctl, + }, +}; + +static int __init init_trace_sysctls(void) +{ + register_sysctl_init("kernel", trace_sysctl_table); + return 0; +} +subsys_initcall(init_trace_sysctls); #ifdef CONFIG_TRACE_EVAL_MAP_FILE /* Map of enums to their values, for "eval_map" file */ @@ -493,7 +528,8 @@ EXPORT_SYMBOL_GPL(unregister_ftrace_export); TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | \ - TRACE_ITER_HASH_PTR | TRACE_ITER_TRACE_PRINTK) + TRACE_ITER_HASH_PTR | TRACE_ITER_TRACE_PRINTK | \ + TRACE_ITER_COPY_MARKER) /* trace_options that are only supported by global_trace */ #define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ @@ -501,7 +537,8 @@ EXPORT_SYMBOL_GPL(unregister_ftrace_export); /* trace_flags that are default zero for instances */ #define ZEROED_TRACE_FLAGS \ - (TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK | TRACE_ITER_TRACE_PRINTK) + (TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK | TRACE_ITER_TRACE_PRINTK | \ + TRACE_ITER_COPY_MARKER) /* * The global_trace is the descriptor that holds the top-level tracing @@ -513,6 +550,9 @@ static struct trace_array global_trace = { static struct trace_array *printk_trace = &global_trace; +/* List of trace_arrays interested in the top level trace_marker */ +static LIST_HEAD(marker_copies); + static __always_inline bool printk_binsafe(struct trace_array *tr) { /* @@ -534,6 +574,28 @@ static void update_printk_trace(struct trace_array *tr) tr->trace_flags |= TRACE_ITER_TRACE_PRINTK; } +/* Returns true if the status of tr changed */ +static bool update_marker_trace(struct trace_array *tr, int enabled) +{ + lockdep_assert_held(&event_mutex); + + if (enabled) { + if (!list_empty(&tr->marker_list)) + return false; + + list_add_rcu(&tr->marker_list, &marker_copies); + tr->trace_flags |= TRACE_ITER_COPY_MARKER; + return true; + } + + if (list_empty(&tr->marker_list)) + return false; + + list_del_init(&tr->marker_list); + tr->trace_flags &= ~TRACE_ITER_COPY_MARKER; + return true; +} + void trace_set_ring_buffer_expanded(struct trace_array *tr) { if (!tr) @@ -1583,6 +1645,39 @@ void tracer_tracing_off(struct trace_array *tr) } /** + * tracer_tracing_disable() - temporary disable the buffer from write + * @tr: The trace array to disable its buffer for + * + * Expects trace_tracing_enable() to re-enable tracing. + * The difference between this and tracer_tracing_off() is that this + * is a counter and can nest, whereas, tracer_tracing_off() can + * be called multiple times and a single trace_tracing_on() will + * enable it. + */ +void tracer_tracing_disable(struct trace_array *tr) +{ + if (WARN_ON_ONCE(!tr->array_buffer.buffer)) + return; + + ring_buffer_record_disable(tr->array_buffer.buffer); +} + +/** + * tracer_tracing_enable() - counter part of tracer_tracing_disable() + * @tr: The trace array that had tracer_tracincg_disable() called on it + * + * This is called after tracer_tracing_disable() has been called on @tr, + * when it's safe to re-enable tracing. + */ +void tracer_tracing_enable(struct trace_array *tr) +{ + if (WARN_ON_ONCE(!tr->array_buffer.buffer)) + return; + + ring_buffer_record_enable(tr->array_buffer.buffer); +} + +/** * tracing_off - turn off tracing buffers * * This function stops the tracing buffers from recording data. @@ -5048,7 +5143,6 @@ int tracing_set_cpumask(struct trace_array *tr, */ if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && !cpumask_test_cpu(cpu, tracing_cpumask_new)) { - atomic_inc(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); ring_buffer_record_disable_cpu(tr->array_buffer.buffer, cpu); #ifdef CONFIG_TRACER_MAX_TRACE ring_buffer_record_disable_cpu(tr->max_buffer.buffer, cpu); @@ -5056,7 +5150,6 @@ int tracing_set_cpumask(struct trace_array *tr, } if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && cpumask_test_cpu(cpu, tracing_cpumask_new)) { - atomic_dec(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); ring_buffer_record_enable_cpu(tr->array_buffer.buffer, cpu); #ifdef CONFIG_TRACER_MAX_TRACE ring_buffer_record_enable_cpu(tr->max_buffer.buffer, cpu); @@ -5189,7 +5282,8 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) { if ((mask == TRACE_ITER_RECORD_TGID) || (mask == TRACE_ITER_RECORD_CMD) || - (mask == TRACE_ITER_TRACE_PRINTK)) + (mask == TRACE_ITER_TRACE_PRINTK) || + (mask == TRACE_ITER_COPY_MARKER)) lockdep_assert_held(&event_mutex); /* do nothing if flag is already set */ @@ -5220,6 +5314,9 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) } } + if (mask == TRACE_ITER_COPY_MARKER) + update_marker_trace(tr, enabled); + if (enabled) tr->trace_flags |= mask; else @@ -6004,6 +6101,7 @@ struct trace_mod_entry { }; struct trace_scratch { + unsigned int clock_id; unsigned long text_addr; unsigned long nr_entries; struct trace_mod_entry entries[]; @@ -6032,6 +6130,7 @@ unsigned long trace_adjust_address(struct trace_array *tr, unsigned long addr) struct trace_module_delta *module_delta; struct trace_scratch *tscratch; struct trace_mod_entry *entry; + unsigned long raddr; int idx = 0, nr_entries; /* If we don't have last boot delta, return the address */ @@ -6045,7 +6144,9 @@ unsigned long trace_adjust_address(struct trace_array *tr, unsigned long addr) module_delta = READ_ONCE(tr->module_delta); if (!module_delta || !tscratch->nr_entries || tscratch->entries[0].mod_addr > addr) { - return addr + tr->text_delta; + raddr = addr + tr->text_delta; + return __is_kernel(raddr) || is_kernel_core_data(raddr) || + is_kernel_rodata(raddr) ? raddr : addr; } /* Note that entries must be sorted. */ @@ -6116,6 +6217,7 @@ static void update_last_data(struct trace_array *tr) if (tr->scratch) { struct trace_scratch *tscratch = tr->scratch; + tscratch->clock_id = tr->clock_id; memset(tscratch->entries, 0, flex_array_size(tscratch, entries, tscratch->nr_entries)); tscratch->nr_entries = 0; @@ -6824,7 +6926,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, ret = trace_seq_to_buffer(&iter->seq, page_address(spd.pages[i]), min((size_t)trace_seq_used(&iter->seq), - PAGE_SIZE)); + (size_t)PAGE_SIZE)); if (ret < 0) { __free_page(spd.pages[i]); break; @@ -7100,11 +7202,9 @@ tracing_free_buffer_release(struct inode *inode, struct file *filp) #define TRACE_MARKER_MAX_SIZE 4096 -static ssize_t -tracing_mark_write(struct file *filp, const char __user *ubuf, - size_t cnt, loff_t *fpos) +static ssize_t write_marker_to_buffer(struct trace_array *tr, const char __user *ubuf, + size_t cnt, unsigned long ip) { - struct trace_array *tr = filp->private_data; struct ring_buffer_event *event; enum event_trigger_type tt = ETT_NONE; struct trace_buffer *buffer; @@ -7118,18 +7218,6 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, #define FAULTED_STR "<faulted>" #define FAULTED_SIZE (sizeof(FAULTED_STR) - 1) /* '\0' is already accounted for */ - if (tracing_disabled) - return -EINVAL; - - if (!(tr->trace_flags & TRACE_ITER_MARKERS)) - return -EINVAL; - - if ((ssize_t)cnt < 0) - return -EINVAL; - - if (cnt > TRACE_MARKER_MAX_SIZE) - cnt = TRACE_MARKER_MAX_SIZE; - meta_size = sizeof(*entry) + 2; /* add '\0' and possible '\n' */ again: size = cnt + meta_size; @@ -7162,7 +7250,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, } entry = ring_buffer_event_data(event); - entry->ip = _THIS_IP_; + entry->ip = ip; len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt); if (len) { @@ -7195,18 +7283,12 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, } static ssize_t -tracing_mark_raw_write(struct file *filp, const char __user *ubuf, +tracing_mark_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *fpos) { struct trace_array *tr = filp->private_data; - struct ring_buffer_event *event; - struct trace_buffer *buffer; - struct raw_data_entry *entry; - ssize_t written; - int size; - int len; - -#define FAULT_SIZE_ID (FAULTED_SIZE + sizeof(int)) + ssize_t written = -ENODEV; + unsigned long ip; if (tracing_disabled) return -EINVAL; @@ -7214,10 +7296,42 @@ tracing_mark_raw_write(struct file *filp, const char __user *ubuf, if (!(tr->trace_flags & TRACE_ITER_MARKERS)) return -EINVAL; - /* The marker must at least have a tag id */ - if (cnt < sizeof(unsigned int)) + if ((ssize_t)cnt < 0) return -EINVAL; + if (cnt > TRACE_MARKER_MAX_SIZE) + cnt = TRACE_MARKER_MAX_SIZE; + + /* The selftests expect this function to be the IP address */ + ip = _THIS_IP_; + + /* The global trace_marker can go to multiple instances */ + if (tr == &global_trace) { + guard(rcu)(); + list_for_each_entry_rcu(tr, &marker_copies, marker_list) { + written = write_marker_to_buffer(tr, ubuf, cnt, ip); + if (written < 0) + break; + } + } else { + written = write_marker_to_buffer(tr, ubuf, cnt, ip); + } + + return written; +} + +static ssize_t write_raw_marker_to_buffer(struct trace_array *tr, + const char __user *ubuf, size_t cnt) +{ + struct ring_buffer_event *event; + struct trace_buffer *buffer; + struct raw_data_entry *entry; + ssize_t written; + int size; + int len; + +#define FAULT_SIZE_ID (FAULTED_SIZE + sizeof(int)) + size = sizeof(*entry) + cnt; if (cnt < FAULT_SIZE_ID) size += FAULT_SIZE_ID - cnt; @@ -7248,6 +7362,40 @@ tracing_mark_raw_write(struct file *filp, const char __user *ubuf, return written; } +static ssize_t +tracing_mark_raw_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *fpos) +{ + struct trace_array *tr = filp->private_data; + ssize_t written = -ENODEV; + +#define FAULT_SIZE_ID (FAULTED_SIZE + sizeof(int)) + + if (tracing_disabled) + return -EINVAL; + + if (!(tr->trace_flags & TRACE_ITER_MARKERS)) + return -EINVAL; + + /* The marker must at least have a tag id */ + if (cnt < sizeof(unsigned int)) + return -EINVAL; + + /* The global trace_marker_raw can go to multiple instances */ + if (tr == &global_trace) { + guard(rcu)(); + list_for_each_entry_rcu(tr, &marker_copies, marker_list) { + written = write_raw_marker_to_buffer(tr, ubuf, cnt); + if (written < 0) + break; + } + } else { + written = write_raw_marker_to_buffer(tr, ubuf, cnt); + } + + return written; +} + static int tracing_clock_show(struct seq_file *m, void *v) { struct trace_array *tr = m->private; @@ -7292,6 +7440,12 @@ int tracing_set_clock(struct trace_array *tr, const char *clockstr) tracing_reset_online_cpus(&tr->max_buffer); #endif + if (tr->scratch && !(tr->flags & TRACE_ARRAY_FL_LAST_BOOT)) { + struct trace_scratch *tscratch = tr->scratch; + + tscratch->clock_id = i; + } + mutex_unlock(&trace_types_lock); return 0; @@ -9517,6 +9671,15 @@ static void setup_trace_scratch(struct trace_array *tr, /* Scan modules to make text delta for modules. */ module_for_each_mod(make_mod_delta, tr); + + /* Set trace_clock as the same of the previous boot. */ + if (tscratch->clock_id != tr->clock_id) { + if (tscratch->clock_id >= ARRAY_SIZE(trace_clocks) || + tracing_set_clock(tr, trace_clocks[tscratch->clock_id].name) < 0) { + pr_info("the previous trace_clock info is not valid."); + goto reset; + } + } return; reset: /* Invalid trace modules */ @@ -9741,6 +9904,7 @@ trace_array_create_systems(const char *name, const char *systems, INIT_LIST_HEAD(&tr->events); INIT_LIST_HEAD(&tr->hist_vars); INIT_LIST_HEAD(&tr->err_log); + INIT_LIST_HEAD(&tr->marker_list); #ifdef CONFIG_MODULES INIT_LIST_HEAD(&tr->mod_events); @@ -9900,6 +10064,9 @@ static int __remove_instance(struct trace_array *tr) if (printk_trace == tr) update_printk_trace(&global_trace); + if (update_marker_trace(tr, 0)) + synchronize_rcu(); + tracing_set_nop(tr); clear_ftrace_function_probes(tr); event_trace_del_tracer(tr); @@ -10075,6 +10242,8 @@ static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore) { struct vfsmount *mnt; struct file_system_type *type; + struct fs_context *fc; + int ret; /* * To maintain backward compatibility for tools that mount @@ -10084,12 +10253,20 @@ static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore) type = get_fs_type("tracefs"); if (!type) return NULL; - mnt = vfs_submount(mntpt, type, "tracefs", NULL); + + fc = fs_context_for_submount(type, mntpt); put_filesystem(type); - if (IS_ERR(mnt)) - return NULL; - mntget(mnt); + if (IS_ERR(fc)) + return ERR_CAST(fc); + + ret = vfs_parse_fs_string(fc, "source", + "tracefs", strlen("tracefs")); + if (!ret) + mnt = fc_mount(fc); + else + mnt = ERR_PTR(ret); + put_fs_context(fc); return mnt; } @@ -10448,7 +10625,7 @@ static void ftrace_dump_one(struct trace_array *tr, enum ftrace_dump_mode dump_m static struct trace_iterator iter; unsigned int old_userobj; unsigned long flags; - int cnt = 0, cpu; + int cnt = 0; /* * Always turn off tracing when we dump. @@ -10465,9 +10642,8 @@ static void ftrace_dump_one(struct trace_array *tr, enum ftrace_dump_mode dump_m /* Simulate the iterator */ trace_init_iter(&iter, tr); - for_each_tracing_cpu(cpu) { - atomic_inc(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); - } + /* While dumping, do not allow the buffer to be enable */ + tracer_tracing_disable(tr); old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; @@ -10526,9 +10702,7 @@ static void ftrace_dump_one(struct trace_array *tr, enum ftrace_dump_mode dump_m tr->trace_flags |= old_userobj; - for_each_tracing_cpu(cpu) { - atomic_dec(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); - } + tracer_tracing_enable(tr); local_irq_restore(flags); } @@ -10968,6 +11142,7 @@ __init static int tracer_alloc_buffers(void) INIT_LIST_HEAD(&global_trace.events); INIT_LIST_HEAD(&global_trace.hist_vars); INIT_LIST_HEAD(&global_trace.err_log); + list_add(&global_trace.marker_list, &marker_copies); list_add(&global_trace.list, &ftrace_trace_arrays); apply_trace_boot_options(); |