From 8c1a49aedb73fb2f15aaa32ad9e2e1c4289f45cb Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Fri, 10 Jan 2014 11:13:54 -0500 Subject: tracing: Pass trace_array to set_flag callback As options (flags) may affect instances instead of being global the set_flag() callbacks need to receive the trace_array descriptor of the instance they will be modifying. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 815c878f409..d7dfc7efc4b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -73,7 +73,8 @@ static struct tracer_flags dummy_tracer_flags = { .opts = dummy_tracer_opt }; -static int dummy_set_flag(u32 old_flags, u32 bit, int set) +static int +dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) { return 0; } @@ -3339,13 +3340,14 @@ static int tracing_trace_options_show(struct seq_file *m, void *v) return 0; } -static int __set_tracer_option(struct tracer *trace, +static int __set_tracer_option(struct trace_array *tr, struct tracer_flags *tracer_flags, struct tracer_opt *opts, int neg) { + struct tracer *trace = tr->current_trace; int ret; - ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); + ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); if (ret) return ret; @@ -3357,8 +3359,9 @@ static int __set_tracer_option(struct tracer *trace, } /* Try to assign a tracer specific option */ -static int set_tracer_option(struct tracer *trace, char *cmp, int neg) +static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) { + struct tracer *trace = tr->current_trace; struct tracer_flags *tracer_flags = trace->flags; struct tracer_opt *opts = NULL; int i; @@ -3367,8 +3370,7 @@ static int set_tracer_option(struct tracer *trace, char *cmp, int neg) opts = &tracer_flags->opts[i]; if (strcmp(cmp, opts->name) == 0) - return __set_tracer_option(trace, trace->flags, - opts, neg); + return __set_tracer_option(tr, trace->flags, opts, neg); } return -EINVAL; @@ -3440,7 +3442,7 @@ static int trace_set_options(struct trace_array *tr, char *option) /* If no option could be set, test the specific tracer options */ if (!trace_options[i]) - ret = set_tracer_option(tr->current_trace, cmp, neg); + ret = set_tracer_option(tr, cmp, neg); mutex_unlock(&trace_types_lock); @@ -5689,7 +5691,7 @@ trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, if (!!(topt->flags->val & topt->opt->bit) != val) { mutex_lock(&trace_types_lock); - ret = __set_tracer_option(topt->tr->current_trace, topt->flags, + ret = __set_tracer_option(topt->tr, topt->flags, topt->opt, !val); mutex_unlock(&trace_types_lock); if (ret) -- cgit v1.2.3-70-g09d2 From bf6065b5c7014ab30383405718c7a6b96d2cbdb2 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Fri, 10 Jan 2014 17:51:01 -0500 Subject: tracing: Pass trace_array to flag_changed callback As options (flags) may affect instances instead of being global the flag_changed() callbacks need to receive the trace_array descriptor of the instance they will be modifying. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 2 +- kernel/trace/trace.h | 2 +- kernel/trace/trace_irqsoff.c | 4 +++- kernel/trace/trace_sched_wakeup.c | 4 +++- 4 files changed, 8 insertions(+), 4 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index d7dfc7efc4b..ee8da93e91e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3393,7 +3393,7 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) /* Give the tracer a chance to approve the change */ if (tr->current_trace->flag_changed) - if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) + if (tr->current_trace->flag_changed(tr, mask, !!enabled)) return -EINVAL; if (enabled) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 649a23d421c..36e44732c65 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -358,7 +358,7 @@ struct tracer { int (*set_flag)(struct trace_array *tr, u32 old_flags, u32 bit, int set); /* Return 0 if OK with change, else return non-zero */ - int (*flag_changed)(struct tracer *tracer, + int (*flag_changed)(struct trace_array *tr, u32 mask, int set); struct tracer *next; struct tracer_flags *flags; diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index fd99b0c183a..4bf812f454e 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -572,8 +572,10 @@ static void irqsoff_function_set(int set) unregister_irqsoff_function(is_graph()); } -static int irqsoff_flag_changed(struct tracer *tracer, u32 mask, int set) +static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set) { + struct tracer *tracer = tr->current_trace; + if (mask & TRACE_ITER_FUNCTION) irqsoff_function_set(set); diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index f0bbdc26102..e14da5e97a6 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -179,8 +179,10 @@ static void wakeup_function_set(int set) unregister_wakeup_function(is_graph()); } -static int wakeup_flag_changed(struct tracer *tracer, u32 mask, int set) +static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set) { + struct tracer *tracer = tr->current_trace; + if (mask & TRACE_ITER_FUNCTION) wakeup_function_set(set); -- cgit v1.2.3-70-g09d2 From 607e2ea167e56db84387f3ab97e59a862e101cab Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Wed, 6 Nov 2013 22:42:48 -0500 Subject: tracing: Set up infrastructure to allow tracers for instances Currently the tracers (function, function_graph, irqsoff, etc) can only be used by the top level tracing directory (not for instances). This sets up the infrastructure to allow instances to be able to run a separate tracer apart from the what the top level tracing is doing. As tracers need to adapt for being used by instances, the tracers must flag if they can be used by instances or not. Currently only the 'nop' tracer can be used by all instances. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 72 ++++++++++++++++++++++++++++++++++++++---------- kernel/trace/trace.h | 1 + kernel/trace/trace_nop.c | 3 +- 3 files changed, 60 insertions(+), 16 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index ee8da93e91e..944cd021aab 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -119,7 +119,7 @@ enum ftrace_dump_mode ftrace_dump_on_oops; /* When set, tracing will stop when a WARN*() is hit */ int __disable_trace_on_warning; -static int tracing_set_tracer(const char *buf); +static int tracing_set_tracer(struct trace_array *tr, const char *buf); #define MAX_TRACER_SIZE 100 static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; @@ -1231,7 +1231,7 @@ int register_tracer(struct tracer *type) printk(KERN_INFO "Starting tracer '%s'\n", type->name); /* Do we want this tracer to start on bootup? */ - tracing_set_tracer(type->name); + tracing_set_tracer(&global_trace, type->name); default_bootup_tracer = NULL; /* disable other selftests, since this will break it. */ tracing_selftest_disabled = true; @@ -3122,27 +3122,52 @@ static int tracing_open(struct inode *inode, struct file *file) return ret; } +/* + * Some tracers are not suitable for instance buffers. + * A tracer is always available for the global array (toplevel) + * or if it explicitly states that it is. + */ +static bool +trace_ok_for_array(struct tracer *t, struct trace_array *tr) +{ + return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; +} + +/* Find the next tracer that this trace array may use */ +static struct tracer * +get_tracer_for_array(struct trace_array *tr, struct tracer *t) +{ + while (t && !trace_ok_for_array(t, tr)) + t = t->next; + + return t; +} + static void * t_next(struct seq_file *m, void *v, loff_t *pos) { + struct trace_array *tr = m->private; struct tracer *t = v; (*pos)++; if (t) - t = t->next; + t = get_tracer_for_array(tr, t->next); return t; } static void *t_start(struct seq_file *m, loff_t *pos) { + struct trace_array *tr = m->private; struct tracer *t; loff_t l = 0; mutex_lock(&trace_types_lock); - for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) - ; + + t = get_tracer_for_array(tr, trace_types); + for (; t && l < *pos; t = t_next(m, t, &l)) + ; return t; } @@ -3177,10 +3202,21 @@ static const struct seq_operations show_traces_seq_ops = { static int show_traces_open(struct inode *inode, struct file *file) { + struct trace_array *tr = inode->i_private; + struct seq_file *m; + int ret; + if (tracing_disabled) return -ENODEV; - return seq_open(file, &show_traces_seq_ops); + ret = seq_open(file, &show_traces_seq_ops); + if (ret) + return ret; + + m = file->private_data; + m->private = tr; + + return 0; } static ssize_t @@ -3871,10 +3907,9 @@ create_trace_option_files(struct trace_array *tr, struct tracer *tracer); static void destroy_trace_option_files(struct trace_option_dentry *topts); -static int tracing_set_tracer(const char *buf) +static int tracing_set_tracer(struct trace_array *tr, const char *buf) { static struct trace_option_dentry *topts; - struct trace_array *tr = &global_trace; struct tracer *t; #ifdef CONFIG_TRACER_MAX_TRACE bool had_max_tr; @@ -3902,6 +3937,12 @@ static int tracing_set_tracer(const char *buf) if (t == tr->current_trace) goto out; + /* Some tracers are only allowed for the top level buffer */ + if (!trace_ok_for_array(t, tr)) { + ret = -EINVAL; + goto out; + } + trace_branch_disable(); tr->current_trace->enabled = false; @@ -3958,6 +3999,7 @@ static ssize_t tracing_set_trace_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { + struct trace_array *tr = filp->private_data; char buf[MAX_TRACER_SIZE+1]; int i; size_t ret; @@ -3977,7 +4019,7 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) buf[i] = 0; - err = tracing_set_tracer(buf); + err = tracing_set_tracer(tr, buf); if (err) return err; @@ -6193,6 +6235,12 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) { int cpu; + trace_create_file("available_tracers", 0444, d_tracer, + tr, &show_traces_fops); + + trace_create_file("current_tracer", 0644, d_tracer, + tr, &set_tracer_fops); + trace_create_file("tracing_cpumask", 0644, d_tracer, tr, &tracing_cpumask_fops); @@ -6245,12 +6293,6 @@ static __init int tracer_init_debugfs(void) init_tracer_debugfs(&global_trace, d_tracer); - trace_create_file("available_tracers", 0444, d_tracer, - &global_trace, &show_traces_fops); - - trace_create_file("current_tracer", 0644, d_tracer, - &global_trace, &set_tracer_fops); - #ifdef CONFIG_TRACER_MAX_TRACE trace_create_file("tracing_max_latency", 0644, d_tracer, &tracing_max_latency, &tracing_max_lat_fops); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 36e44732c65..ea51bb2004d 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -364,6 +364,7 @@ struct tracer { struct tracer_flags *flags; bool print_max; bool enabled; + bool allow_instances; #ifdef CONFIG_TRACER_MAX_TRACE bool use_max_tr; #endif diff --git a/kernel/trace/trace_nop.c b/kernel/trace/trace_nop.c index f3984098c0d..69a5cc94c01 100644 --- a/kernel/trace/trace_nop.c +++ b/kernel/trace/trace_nop.c @@ -96,6 +96,7 @@ struct tracer nop_trace __read_mostly = .selftest = trace_selftest_startup_nop, #endif .flags = &nop_flags, - .set_flag = nop_set_flag + .set_flag = nop_set_flag, + .allow_instances = true, }; -- cgit v1.2.3-70-g09d2 From f1b21c9a40704dfdf7b8423c7d2969ea31c9857d Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Tue, 14 Jan 2014 12:33:33 -0500 Subject: tracing: Only let top level have option files Currently, only the top level instance can have tracing options. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 944cd021aab..da9543cdbe7 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3968,9 +3968,11 @@ static int tracing_set_tracer(struct trace_array *tr, const char *buf) free_snapshot(tr); } #endif - destroy_trace_option_files(topts); - - topts = create_trace_option_files(tr, t); + /* Currently, only the top instance has options */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { + destroy_trace_option_files(topts); + topts = create_trace_option_files(tr, t); + } #ifdef CONFIG_TRACER_MAX_TRACE if (t->use_max_tr && !had_max_tr) { -- cgit v1.2.3-70-g09d2 From 6b450d2533e2c1c71fbe7f1bdce0bb1c9f813030 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Tue, 14 Jan 2014 08:43:01 -0500 Subject: tracing: Disable tracers before deletion of instance When an instance is about to be deleted, make sure the tracer is set to nop. If it isn't reset the tracer and set it to the nop tracer, otherwise memory leaks and bad pointers may result. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index da9543cdbe7..7d5913bb46e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3907,6 +3907,23 @@ create_trace_option_files(struct trace_array *tr, struct tracer *tracer); static void destroy_trace_option_files(struct trace_option_dentry *topts); +/* + * Used to clear out the tracer before deletion of an instance. + * Must have trace_types_lock held. + */ +static void tracing_set_nop(struct trace_array *tr) +{ + if (tr->current_trace == &nop_trace) + return; + + tr->current_trace->enabled = false; + + if (tr->current_trace->reset) + tr->current_trace->reset(tr); + + tr->current_trace = &nop_trace; +} + static int tracing_set_tracer(struct trace_array *tr, const char *buf) { static struct trace_option_dentry *topts; @@ -6142,6 +6159,7 @@ static int instance_delete(const char *name) list_del(&tr->list); + tracing_set_nop(tr); event_trace_del_tracer(tr); debugfs_remove_recursive(tr->dir); free_percpu(tr->trace_buffer.data); -- cgit v1.2.3-70-g09d2 From 50512ab576e1ce29953c9259e1f36ce16f350f20 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Tue, 14 Jan 2014 08:52:35 -0500 Subject: tracing: Convert tracer->enabled to counter As tracers will soon be used by instances, the tracer enabled field needs to be converted to a counter instead of a boolean. This counter is protected by the trace_types_lock mutex. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 6 +++--- kernel/trace/trace.h | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 7d5913bb46e..f9f22c43503 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3916,7 +3916,7 @@ static void tracing_set_nop(struct trace_array *tr) if (tr->current_trace == &nop_trace) return; - tr->current_trace->enabled = false; + tr->current_trace->enabled--; if (tr->current_trace->reset) tr->current_trace->reset(tr); @@ -3962,7 +3962,7 @@ static int tracing_set_tracer(struct trace_array *tr, const char *buf) trace_branch_disable(); - tr->current_trace->enabled = false; + tr->current_trace->enabled--; if (tr->current_trace->reset) tr->current_trace->reset(tr); @@ -4006,7 +4006,7 @@ static int tracing_set_tracer(struct trace_array *tr, const char *buf) } tr->current_trace = t; - tr->current_trace->enabled = true; + tr->current_trace->enabled++; trace_branch_enable(tr); out: mutex_unlock(&trace_types_lock); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index ea51bb2004d..86915b220bb 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -362,8 +362,8 @@ struct tracer { u32 mask, int set); struct tracer *next; struct tracer_flags *flags; + int enabled; bool print_max; - bool enabled; bool allow_instances; #ifdef CONFIG_TRACER_MAX_TRACE bool use_max_tr; -- cgit v1.2.3-70-g09d2 From 591dffdade9f07692a7dd3ed16830ec24e901ece Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Fri, 10 Jan 2014 16:17:45 -0500 Subject: ftrace: Allow for function tracing instance to filter functions Create a "set_ftrace_filter" and "set_ftrace_notrace" files in the instance directories to let users filter of functions to trace for the given instance. Signed-off-by: Steven Rostedt --- include/linux/ftrace.h | 2 ++ kernel/trace/ftrace.c | 39 ++++++++++++++++++++++++++++++++++----- kernel/trace/trace.c | 4 ++++ kernel/trace/trace.h | 25 ++++++++++++++++++++++++- kernel/trace/trace_functions.c | 40 ++++++++++++++++++++++++++++++++-------- 5 files changed, 96 insertions(+), 14 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index ef1607ed704..e6141be2fad 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -92,6 +92,7 @@ typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, * STUB - The ftrace_ops is just a place holder. * INITIALIZED - The ftrace_ops has already been initialized (first use time * register_ftrace_function() is called, it will initialized the ops) + * DELETED - The ops are being deleted, do not let them be registered again. */ enum { FTRACE_OPS_FL_ENABLED = 1 << 0, @@ -103,6 +104,7 @@ enum { FTRACE_OPS_FL_RECURSION_SAFE = 1 << 6, FTRACE_OPS_FL_STUB = 1 << 7, FTRACE_OPS_FL_INITIALIZED = 1 << 8, + FTRACE_OPS_FL_DELETED = 1 << 9, }; /* diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 2b3e23991c8..dcee546f21b 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -436,6 +436,9 @@ static int remove_ftrace_list_ops(struct ftrace_ops **list, static int __register_ftrace_function(struct ftrace_ops *ops) { + if (ops->flags & FTRACE_OPS_FL_DELETED) + return -EINVAL; + if (FTRACE_WARN_ON(ops == &global_ops)) return -EINVAL; @@ -4112,6 +4115,36 @@ static const struct file_operations ftrace_graph_notrace_fops = { }; #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ +void ftrace_create_filter_files(struct ftrace_ops *ops, + struct dentry *parent) +{ + + trace_create_file("set_ftrace_filter", 0644, parent, + ops, &ftrace_filter_fops); + + trace_create_file("set_ftrace_notrace", 0644, parent, + ops, &ftrace_notrace_fops); +} + +/* + * The name "destroy_filter_files" is really a misnomer. Although + * in the future, it may actualy delete the files, but this is + * really intended to make sure the ops passed in are disabled + * and that when this function returns, the caller is free to + * free the ops. + * + * The "destroy" name is only to match the "create" name that this + * should be paired with. + */ +void ftrace_destroy_filter_files(struct ftrace_ops *ops) +{ + mutex_lock(&ftrace_lock); + if (ops->flags & FTRACE_OPS_FL_ENABLED) + ftrace_shutdown(ops, 0); + ops->flags |= FTRACE_OPS_FL_DELETED; + mutex_unlock(&ftrace_lock); +} + static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { @@ -4121,11 +4154,7 @@ static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) trace_create_file("enabled_functions", 0444, d_tracer, NULL, &ftrace_enabled_fops); - trace_create_file("set_ftrace_filter", 0644, d_tracer, - &global_ops, &ftrace_filter_fops); - - trace_create_file("set_ftrace_notrace", 0644, d_tracer, - &global_ops, &ftrace_notrace_fops); + ftrace_create_filter_files(&global_ops, d_tracer); #ifdef CONFIG_FUNCTION_GRAPH_TRACER trace_create_file("set_graph_function", 0444, d_tracer, diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f9f22c43503..d95ec2876bb 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -6161,6 +6161,7 @@ static int instance_delete(const char *name) tracing_set_nop(tr); event_trace_del_tracer(tr); + ftrace_destroy_function_files(tr); debugfs_remove_recursive(tr->dir); free_percpu(tr->trace_buffer.data); ring_buffer_free(tr->trace_buffer.buffer); @@ -6291,6 +6292,9 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) trace_create_file("tracing_on", 0644, d_tracer, tr, &rb_simple_fops); + if (ftrace_create_function_files(tr, d_tracer)) + WARN(1, "Could not allocate function filter files"); + #ifdef CONFIG_TRACER_SNAPSHOT trace_create_file("snapshot", 0644, d_tracer, tr, &snapshot_fops); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 35cca055da0..ffc314b7e92 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -819,13 +819,36 @@ static inline int ftrace_trace_task(struct task_struct *task) return test_tsk_trace_trace(task); } extern int ftrace_is_dead(void); +int ftrace_create_function_files(struct trace_array *tr, + struct dentry *parent); +void ftrace_destroy_function_files(struct trace_array *tr); #else static inline int ftrace_trace_task(struct task_struct *task) { return 1; } static inline int ftrace_is_dead(void) { return 0; } -#endif +static inline int +ftrace_create_function_files(struct trace_array *tr, + struct dentry *parent) +{ + return 0; +} +static inline void ftrace_destroy_function_files(struct trace_array *tr) { } +#endif /* CONFIG_FUNCTION_TRACER */ + +#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) +void ftrace_create_filter_files(struct ftrace_ops *ops, + struct dentry *parent); +void ftrace_destroy_filter_files(struct ftrace_ops *ops); +#else +/* + * The ops parameter passed in is usually undefined. + * This must be a macro. + */ +#define ftrace_create_filter_files(ops, parent) do { } while (0) +#define ftrace_destroy_filter_files(ops) do { } while (0) +#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ int ftrace_event_is_function(struct ftrace_event_call *call); diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index 3f8dc1ce8b9..5b781d2be38 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -52,10 +52,34 @@ static int allocate_ftrace_ops(struct trace_array *tr) return 0; } + +int ftrace_create_function_files(struct trace_array *tr, + struct dentry *parent) +{ + int ret; + + /* The top level array uses the "global_ops". */ + if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) { + ret = allocate_ftrace_ops(tr); + if (ret) + return ret; + } + + ftrace_create_filter_files(tr->ops, parent); + + return 0; +} + +void ftrace_destroy_function_files(struct trace_array *tr) +{ + ftrace_destroy_filter_files(tr->ops); + kfree(tr->ops); + tr->ops = NULL; +} + static int function_trace_init(struct trace_array *tr) { struct ftrace_ops *ops; - int ret; if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { /* There's only one global tr */ @@ -69,10 +93,13 @@ static int function_trace_init(struct trace_array *tr) else ops = &trace_ops; tr->ops = ops; - } else { - ret = allocate_ftrace_ops(tr); - if (ret) - return ret; + } else if (!tr->ops) { + /* + * Instance trace_arrays get their ops allocated + * at instance creation. Unless it failed + * the allocation. + */ + return -ENOMEM; } tr->trace_buffer.cpu = get_cpu(); @@ -87,9 +114,6 @@ static void function_trace_reset(struct trace_array *tr) { tracing_stop_function_trace(tr); tracing_stop_cmdline_record(); - if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) - kfree(tr->ops); - tr->ops = NULL; } static void function_trace_start(struct trace_array *tr) -- cgit v1.2.3-70-g09d2 From e1e232ca6b8faa210e5509f17d55519b4392524f Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 10 Feb 2014 23:38:46 -0500 Subject: tracing: Add trace_clock= kernel parameter Being able to change the trace clock at boot can be advantageous if you need a better source of when things happen across CPUs. The default trace clock is the fastest, but it uses local clocks which may not be synced across CPUs and it does not let you know when events took place with respect to events on other CPUs. The global trace clock can help in this case, and if you do not care about timings, the counter "clock" is the best, as that is just a simple atomic counter that is incremented for every event. Usage is to add "trace_clock=counter" on the kernel command line. You can replace counter with "global" or any of the clocks listed in /sys/kernel/debug/tracing/trace_clock Suggested-by: Thomas Gleixner Tested-by: Thomas Gleixner Reviewed-by: Thomas Gleixner Appreciated-by: Thomas Gleixner Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 61 ++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 45 insertions(+), 16 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index d95ec2876bb..c90f55d80f8 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -181,6 +181,17 @@ static int __init set_trace_boot_options(char *str) } __setup("trace_options=", set_trace_boot_options); +static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; +static char *trace_boot_clock __initdata; + +static int __init set_trace_boot_clock(char *str) +{ + strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); + trace_boot_clock = trace_boot_clock_buf; + return 0; +} +__setup("trace_clock=", set_trace_boot_clock); + unsigned long long ns2usecs(cycle_t nsec) { @@ -4746,25 +4757,10 @@ static int tracing_clock_show(struct seq_file *m, void *v) return 0; } -static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, - size_t cnt, loff_t *fpos) +static int tracing_set_clock(struct trace_array *tr, const char *clockstr) { - struct seq_file *m = filp->private_data; - struct trace_array *tr = m->private; - char buf[64]; - const char *clockstr; int i; - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - clockstr = strstrip(buf); - for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { if (strcmp(trace_clocks[i].name, clockstr) == 0) break; @@ -4792,6 +4788,32 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, mutex_unlock(&trace_types_lock); + return 0; +} + +static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *fpos) +{ + struct seq_file *m = filp->private_data; + struct trace_array *tr = m->private; + char buf[64]; + const char *clockstr; + int ret; + + if (cnt >= sizeof(buf)) + return -EINVAL; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = 0; + + clockstr = strstrip(buf); + + ret = tracing_set_clock(tr, clockstr); + if (ret) + return ret; + *fpos += cnt; return cnt; @@ -6574,6 +6596,13 @@ __init static int tracer_alloc_buffers(void) trace_init_cmdlines(); + if (trace_boot_clock) { + ret = tracing_set_clock(&global_trace, trace_boot_clock); + if (ret < 0) + pr_warning("Trace clock %s not defined, going back to default\n", + trace_boot_clock); + } + /* * register_tracer() might reference current_trace, so it * needs to be set before we register anything. This is -- cgit v1.2.3-70-g09d2 From 2c4a33aba5f9ea3a28f2e40351f078d95f00786b Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Tue, 25 Mar 2014 23:39:41 -0400 Subject: tracing: Fix traceon trigger condition to actually turn tracing on While working on my tutorial for 2014 Linux Collaboration Summit I found that the traceon trigger did not work when conditions were used. The other triggers worked fine though. Looking into it, it is because of the way the triggers use the ring buffer to store the fields it will use for the condition. But if tracing is off, nothing is stored in the buffer, and the tracepoint exits before calling the trigger to test the condition. This is fine for all the triggers that only work when tracing is on, but for traceon trigger that is to work when tracing is off, nothing happens. The fix is simple, just use a temp ring buffer to record the event if tracing is off and the event has a trace event conditional trigger enabled. The rest of the tracepoint code will work just fine, but the tracepoint wont be recorded in the other buffers. Cc: Tom Zanussi Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 815c878f409..24c1f238255 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1600,15 +1600,31 @@ void trace_buffer_unlock_commit(struct ring_buffer *buffer, } EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); +static struct ring_buffer *temp_buffer; + struct ring_buffer_event * trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, struct ftrace_event_file *ftrace_file, int type, unsigned long len, unsigned long flags, int pc) { + struct ring_buffer_event *entry; + *current_rb = ftrace_file->tr->trace_buffer.buffer; - return trace_buffer_lock_reserve(*current_rb, + entry = trace_buffer_lock_reserve(*current_rb, type, len, flags, pc); + /* + * If tracing is off, but we have triggers enabled + * we still need to look at the event data. Use the temp_buffer + * to store the trace event for the tigger to use. It's recusive + * safe and will not be recorded anywhere. + */ + if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { + *current_rb = temp_buffer; + entry = trace_buffer_lock_reserve(*current_rb, + type, len, flags, pc); + } + return entry; } EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); @@ -6494,11 +6510,16 @@ __init static int tracer_alloc_buffers(void) raw_spin_lock_init(&global_trace.start_lock); + /* Used for event triggers */ + temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); + if (!temp_buffer) + goto out_free_cpumask; + /* TODO: make the number of buffers hot pluggable with CPUS */ if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); WARN_ON(1); - goto out_free_cpumask; + goto out_free_temp_buffer; } if (global_trace.buffer_disabled) @@ -6540,6 +6561,8 @@ __init static int tracer_alloc_buffers(void) return 0; +out_free_temp_buffer: + ring_buffer_free(temp_buffer); out_free_cpumask: free_percpu(global_trace.trace_buffer.data); #ifdef CONFIG_TRACER_MAX_TRACE -- cgit v1.2.3-70-g09d2 From fbb32750a62df75d1ffea547f3908b21c5496d9f Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 2 Feb 2014 21:09:54 -0500 Subject: pipe: kill ->map() and ->unmap() all pipe_buffer_operations have the same instances of those... Signed-off-by: Al Viro --- drivers/char/virtio_console.c | 4 +-- fs/fuse/dev.c | 6 ++-- fs/pipe.c | 70 ++++++++++--------------------------------- fs/splice.c | 24 +++++---------- include/linux/pipe_fs_i.h | 19 ------------ kernel/relay.c | 2 -- kernel/trace/trace.c | 4 --- 7 files changed, 29 insertions(+), 100 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 6928d094451..60aafb8a1f2 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -901,9 +901,9 @@ static int pipe_to_sg(struct pipe_inode_info *pipe, struct pipe_buffer *buf, if (len + offset > PAGE_SIZE) len = PAGE_SIZE - offset; - src = buf->ops->map(pipe, buf, 1); + src = kmap_atomic(buf->page); memcpy(page_address(page) + offset, src + buf->offset, len); - buf->ops->unmap(pipe, buf, src); + kunmap_atomic(src); sg_set_page(&(sgl->sg[sgl->n]), page, len, offset); } diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index f90af6fe688..aac71ce373e 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -667,7 +667,7 @@ static void fuse_copy_finish(struct fuse_copy_state *cs) struct pipe_buffer *buf = cs->currbuf; if (!cs->write) { - buf->ops->unmap(cs->pipe, buf, cs->mapaddr); + kunmap_atomic(cs->mapaddr); } else { kunmap_atomic(cs->mapaddr); buf->len = PAGE_SIZE - cs->len; @@ -706,7 +706,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) BUG_ON(!cs->nr_segs); cs->currbuf = buf; - cs->mapaddr = buf->ops->map(cs->pipe, buf, 1); + cs->mapaddr = kmap_atomic(buf->page); cs->len = buf->len; cs->buf = cs->mapaddr + buf->offset; cs->pipebufs++; @@ -874,7 +874,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) out_fallback_unlock: unlock_page(newpage); out_fallback: - cs->mapaddr = buf->ops->map(cs->pipe, buf, 1); + cs->mapaddr = kmap_atomic(buf->page); cs->buf = cs->mapaddr + buf->offset; err = lock_request(cs->fc, cs->req); diff --git a/fs/pipe.c b/fs/pipe.c index 78fd0d0788d..6679c95eb4c 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -225,52 +225,6 @@ static void anon_pipe_buf_release(struct pipe_inode_info *pipe, page_cache_release(page); } -/** - * generic_pipe_buf_map - virtually map a pipe buffer - * @pipe: the pipe that the buffer belongs to - * @buf: the buffer that should be mapped - * @atomic: whether to use an atomic map - * - * Description: - * This function returns a kernel virtual address mapping for the - * pipe_buffer passed in @buf. If @atomic is set, an atomic map is provided - * and the caller has to be careful not to fault before calling - * the unmap function. - * - * Note that this function calls kmap_atomic() if @atomic != 0. - */ -void *generic_pipe_buf_map(struct pipe_inode_info *pipe, - struct pipe_buffer *buf, int atomic) -{ - if (atomic) { - buf->flags |= PIPE_BUF_FLAG_ATOMIC; - return kmap_atomic(buf->page); - } - - return kmap(buf->page); -} -EXPORT_SYMBOL(generic_pipe_buf_map); - -/** - * generic_pipe_buf_unmap - unmap a previously mapped pipe buffer - * @pipe: the pipe that the buffer belongs to - * @buf: the buffer that should be unmapped - * @map_data: the data that the mapping function returned - * - * Description: - * This function undoes the mapping that ->map() provided. - */ -void generic_pipe_buf_unmap(struct pipe_inode_info *pipe, - struct pipe_buffer *buf, void *map_data) -{ - if (buf->flags & PIPE_BUF_FLAG_ATOMIC) { - buf->flags &= ~PIPE_BUF_FLAG_ATOMIC; - kunmap_atomic(map_data); - } else - kunmap(buf->page); -} -EXPORT_SYMBOL(generic_pipe_buf_unmap); - /** * generic_pipe_buf_steal - attempt to take ownership of a &pipe_buffer * @pipe: the pipe that the buffer belongs to @@ -351,8 +305,6 @@ EXPORT_SYMBOL(generic_pipe_buf_release); static const struct pipe_buf_operations anon_pipe_buf_ops = { .can_merge = 1, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = anon_pipe_buf_release, .steal = generic_pipe_buf_steal, @@ -361,8 +313,6 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = { static const struct pipe_buf_operations packet_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = anon_pipe_buf_release, .steal = generic_pipe_buf_steal, @@ -410,9 +360,15 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov, atomic = !iov_fault_in_pages_write(iov, chars); redo: - addr = ops->map(pipe, buf, atomic); + if (atomic) + addr = kmap_atomic(buf->page); + else + addr = kmap(buf->page); error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars, atomic); - ops->unmap(pipe, buf, addr); + if (atomic) + kunmap_atomic(addr); + else + kunmap(buf->page); if (unlikely(error)) { /* * Just retry with the slow path if we failed. @@ -538,10 +494,16 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov, iov_fault_in_pages_read(iov, chars); redo1: - addr = ops->map(pipe, buf, atomic); + if (atomic) + addr = kmap_atomic(buf->page); + else + addr = kmap(buf->page); error = pipe_iov_copy_from_user(offset + addr, iov, chars, atomic); - ops->unmap(pipe, buf, addr); + if (atomic) + kunmap_atomic(addr); + else + kunmap(buf->page); ret = error; do_wakeup = 1; if (error) { diff --git a/fs/splice.c b/fs/splice.c index 12028fa41de..ca3bfbd970f 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -136,8 +136,6 @@ error: const struct pipe_buf_operations page_cache_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = page_cache_pipe_buf_confirm, .release = page_cache_pipe_buf_release, .steal = page_cache_pipe_buf_steal, @@ -156,8 +154,6 @@ static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe, static const struct pipe_buf_operations user_page_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = page_cache_pipe_buf_release, .steal = user_page_pipe_buf_steal, @@ -547,8 +543,6 @@ EXPORT_SYMBOL(generic_file_splice_read); static const struct pipe_buf_operations default_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = generic_pipe_buf_release, .steal = generic_pipe_buf_steal, @@ -564,8 +558,6 @@ static int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe, /* Pipe buffer operations for a socket and similar. */ const struct pipe_buf_operations nosteal_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = generic_pipe_buf_release, .steal = generic_pipe_buf_nosteal, @@ -767,13 +759,13 @@ int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf, goto out; if (buf->page != page) { - char *src = buf->ops->map(pipe, buf, 1); + char *src = kmap_atomic(buf->page); char *dst = kmap_atomic(page); memcpy(dst + offset, src + buf->offset, this_len); flush_dcache_page(page); kunmap_atomic(dst); - buf->ops->unmap(pipe, buf, src); + kunmap_atomic(src); } ret = pagecache_write_end(file, mapping, sd->pos, this_len, this_len, page, fsdata); @@ -1067,9 +1059,9 @@ static int write_pipe_buf(struct pipe_inode_info *pipe, struct pipe_buffer *buf, void *data; loff_t tmp = sd->pos; - data = buf->ops->map(pipe, buf, 0); + data = kmap(buf->page); ret = __kernel_write(sd->u.file, data + buf->offset, sd->len, &tmp); - buf->ops->unmap(pipe, buf, data); + kunmap(buf->page); return ret; } @@ -1536,10 +1528,10 @@ static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf, * pages and doing an atomic copy */ if (!fault_in_pages_writeable(sd->u.userptr, sd->len)) { - src = buf->ops->map(pipe, buf, 1); + src = kmap_atomic(buf->page); ret = __copy_to_user_inatomic(sd->u.userptr, src + buf->offset, sd->len); - buf->ops->unmap(pipe, buf, src); + kunmap_atomic(src); if (!ret) { ret = sd->len; goto out; @@ -1549,13 +1541,13 @@ static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf, /* * No dice, use slow non-atomic map and copy */ - src = buf->ops->map(pipe, buf, 0); + src = kmap(buf->page); ret = sd->len; if (copy_to_user(sd->u.userptr, src + buf->offset, sd->len)) ret = -EFAULT; - buf->ops->unmap(pipe, buf, src); + kunmap(buf->page); out: if (ret > 0) sd->u.userptr += ret; diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index ab575269211..6dffcebe610 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -82,23 +82,6 @@ struct pipe_buf_operations { */ int can_merge; - /* - * ->map() returns a virtual address mapping of the pipe buffer. - * The last integer flag reflects whether this should be an atomic - * mapping or not. The atomic map is faster, however you can't take - * page faults before calling ->unmap() again. So if you need to eg - * access user data through copy_to/from_user(), then you must get - * a non-atomic map. ->map() uses the kmap_atomic slot for - * atomic maps, you have to be careful if mapping another page as - * source or destination for a copy. - */ - void * (*map)(struct pipe_inode_info *, struct pipe_buffer *, int); - - /* - * Undoes ->map(), finishes the virtual mapping of the pipe buffer. - */ - void (*unmap)(struct pipe_inode_info *, struct pipe_buffer *, void *); - /* * ->confirm() verifies that the data in the pipe buffer is there * and that the contents are good. If the pages in the pipe belong @@ -150,8 +133,6 @@ struct pipe_inode_info *alloc_pipe_info(void); void free_pipe_info(struct pipe_inode_info *); /* Generic pipe buffer ops functions */ -void *generic_pipe_buf_map(struct pipe_inode_info *, struct pipe_buffer *, int); -void generic_pipe_buf_unmap(struct pipe_inode_info *, struct pipe_buffer *, void *); void generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_confirm(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *); diff --git a/kernel/relay.c b/kernel/relay.c index 5001c9887db..98833f664fb 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -1195,8 +1195,6 @@ static void relay_pipe_buf_release(struct pipe_inode_info *pipe, static const struct pipe_buf_operations relay_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = relay_pipe_buf_release, .steal = generic_pipe_buf_steal, diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 24c1f238255..7511de35257 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4316,8 +4316,6 @@ static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, static const struct pipe_buf_operations tracing_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = generic_pipe_buf_release, .steal = generic_pipe_buf_steal, @@ -5194,8 +5192,6 @@ static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, /* Pipe buffer operations for a buffer. */ static const struct pipe_buf_operations buffer_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = buffer_pipe_buf_release, .steal = generic_pipe_buf_steal, -- cgit v1.2.3-70-g09d2 From 17a280ea8111c66791c18c0353b7986aafcb24fe Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Thu, 10 Apr 2014 22:43:37 -0400 Subject: tracing: Add missing function triggers dump and cpudump to README The debugfs tracing README file lists all the function triggers except for dump and cpudump. These should be added too. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 9be67c5e5b0..e3e665685ee 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3611,6 +3611,8 @@ static const char readme_msg[] = #ifdef CONFIG_TRACER_SNAPSHOT "\t\t snapshot\n" #endif + "\t\t dump\n" + "\t\t cpudump\n" "\t example: echo do_fault:traceoff > set_ftrace_filter\n" "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" "\t The first one will disable tracing every time do_fault is hit\n" -- cgit v1.2.3-70-g09d2 From a786c06d9f2719203c00b3d97b21f9a96980d0b5 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 11 Apr 2014 12:01:03 -0400 Subject: missing bits of "splice: fix racy pipe->buffers uses" that commit has fixed only the parts of that mess in fs/splice.c itself; there had been more in several other ->splice_read() instances... Signed-off-by: Al Viro --- kernel/relay.c | 2 +- kernel/trace/trace.c | 4 ++-- mm/shmem.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/relay.c b/kernel/relay.c index 98833f664fb..7d38607649a 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -1251,7 +1251,7 @@ static ssize_t subbuf_splice_actor(struct file *in, subbuf_pages = rbuf->chan->alloc_size >> PAGE_SHIFT; pidx = (read_start / PAGE_SIZE) % subbuf_pages; poff = read_start & ~PAGE_MASK; - nr_pages = min_t(unsigned int, subbuf_pages, pipe->buffers); + nr_pages = min_t(unsigned int, subbuf_pages, spd.nr_pages_max); for (total_len = 0; spd.nr_pages < nr_pages; spd.nr_pages++) { unsigned int this_len, this_end, private; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 7511de35257..27924caaa12 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4410,7 +4410,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, trace_access_lock(iter->cpu_file); /* Fill as many pages as possible. */ - for (i = 0, rem = len; i < pipe->buffers && rem; i++) { + for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { spd.pages[i] = alloc_page(GFP_KERNEL); if (!spd.pages[i]) break; @@ -5267,7 +5267,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, trace_access_lock(iter->cpu_file); entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); - for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { + for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { struct page *page; int r; diff --git a/mm/shmem.c b/mm/shmem.c index 17d3799d04b..37400a148f2 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1613,7 +1613,7 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos, index = *ppos >> PAGE_CACHE_SHIFT; loff = *ppos & ~PAGE_CACHE_MASK; req_pages = (len + loff + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; - nr_pages = min(req_pages, pipe->buffers); + nr_pages = min(req_pages, spd.nr_pages_max); spd.nr_pages = find_get_pages_contig(mapping, index, nr_pages, spd.pages); -- cgit v1.2.3-70-g09d2