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Diffstat (limited to 'include/linux/marker.h')
-rw-r--r-- | include/linux/marker.h | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/include/linux/marker.h b/include/linux/marker.h new file mode 100644 index 0000000..8038d89 --- /dev/null +++ b/include/linux/marker.h @@ -0,0 +1,130 @@ +#ifndef _LINUX_MARKER_H +#define _LINUX_MARKER_H + +/* + * Code markup for dynamic and static tracing. + * + * See Documentation/marker.txt. + * + * (C) Copyright 2006 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include <linux/types.h> + +struct module; +struct marker; + +/** + * marker_probe_func - Type of a marker probe function + * @mdata: pointer of type struct marker + * @private_data: caller site private data + * @fmt: format string + * @...: variable argument list + * + * Type of marker probe functions. They receive the mdata and need to parse the + * format string to recover the variable argument list. + */ +typedef void marker_probe_func(const struct marker *mdata, + void *private_data, const char *fmt, ...); + +struct marker { + const char *name; /* Marker name */ + const char *format; /* Marker format string, describing the + * variable argument list. + */ + char state; /* Marker state. */ + marker_probe_func *call;/* Probe handler function pointer */ + void *private; /* Private probe data */ +} __attribute__((aligned(8))); + +#ifdef CONFIG_MARKERS + +/* + * Note : the empty asm volatile with read constraint is used here instead of a + * "used" attribute to fix a gcc 4.1.x bug. + * Make sure the alignment of the structure in the __markers section will + * not add unwanted padding between the beginning of the section and the + * structure. Force alignment to the same alignment as the section start. + */ +#define __trace_mark(name, call_data, format, args...) \ + do { \ + static const char __mstrtab_name_##name[] \ + __attribute__((section("__markers_strings"))) \ + = #name; \ + static const char __mstrtab_format_##name[] \ + __attribute__((section("__markers_strings"))) \ + = format; \ + static struct marker __mark_##name \ + __attribute__((section("__markers"), aligned(8))) = \ + { __mstrtab_name_##name, __mstrtab_format_##name, \ + 0, __mark_empty_function, NULL }; \ + asm volatile("" : : "i" (&__mark_##name)); \ + __mark_check_format(format, ## args); \ + if (unlikely(__mark_##name.state)) { \ + preempt_disable(); \ + (*__mark_##name.call) \ + (&__mark_##name, call_data, \ + format, ## args); \ + preempt_enable(); \ + } \ + } while (0) + +extern void marker_update_probe_range(struct marker *begin, + struct marker *end, struct module *probe_module, int *refcount); +#else /* !CONFIG_MARKERS */ +#define __trace_mark(name, call_data, format, args...) \ + __mark_check_format(format, ## args) +static inline void marker_update_probe_range(struct marker *begin, + struct marker *end, struct module *probe_module, int *refcount) +{ } +#endif /* CONFIG_MARKERS */ + +/** + * trace_mark - Marker + * @name: marker name, not quoted. + * @format: format string + * @args...: variable argument list + * + * Places a marker. + */ +#define trace_mark(name, format, args...) \ + __trace_mark(name, NULL, format, ## args) + +#define MARK_MAX_FORMAT_LEN 1024 + +/** + * MARK_NOARGS - Format string for a marker with no argument. + */ +#define MARK_NOARGS " " + +/* To be used for string format validity checking with gcc */ +static inline void __printf(1, 2) __mark_check_format(const char *fmt, ...) +{ +} + +extern marker_probe_func __mark_empty_function; + +/* + * Connect a probe to a marker. + * private data pointer must be a valid allocated memory address, or NULL. + */ +extern int marker_probe_register(const char *name, const char *format, + marker_probe_func *probe, void *private); + +/* + * Returns the private data given to marker_probe_register. + */ +extern void *marker_probe_unregister(const char *name); +/* + * Unregister a marker by providing the registered private data. + */ +extern void *marker_probe_unregister_private_data(void *private); + +extern int marker_arm(const char *name); +extern int marker_disarm(const char *name); +extern void *marker_get_private_data(const char *name); + +#endif |