diff options
| -rw-r--r-- | Documentation/trace/ftrace.rst | 9 | ||||
| -rw-r--r-- | include/linux/trace_events.h | 8 | ||||
| -rw-r--r-- | include/linux/trace_seq.h | 12 | ||||
| -rw-r--r-- | include/trace/stages/stage3_trace_output.h | 4 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 1 | ||||
| -rw-r--r-- | kernel/trace/trace_output.c | 30 | ||||
| -rw-r--r-- | kernel/trace/trace_seq.c | 29 |
7 files changed, 82 insertions, 11 deletions
diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst index d1f313a5f4ad..639f4d95732f 100644 --- a/Documentation/trace/ftrace.rst +++ b/Documentation/trace/ftrace.rst @@ -1290,6 +1290,15 @@ Here are the available options: This will be useful if you want to find out which hashed value is corresponding to the real value in trace log. + bitmask-list + When enabled, bitmasks are displayed as a human-readable list of + ranges (e.g., 0,2-5,7) using the printk "%*pbl" format specifier. + When disabled (the default), bitmasks are displayed in the + traditional hexadecimal bitmap representation. The list format is + particularly useful for tracing CPU masks and other large bitmasks + where individual bit positions are more meaningful than their + hexadecimal encoding. + record-cmd When any event or tracer is enabled, a hook is enabled in the sched_switch trace point to fill comm cache diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 3690221ba3d8..0a2b8229b999 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -38,7 +38,10 @@ const char *trace_print_symbols_seq_u64(struct trace_seq *p, *symbol_array); #endif -const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr, +struct trace_iterator; +struct trace_event; + +const char *trace_print_bitmask_seq(struct trace_iterator *iter, void *bitmask_ptr, unsigned int bitmask_size); const char *trace_print_hex_seq(struct trace_seq *p, @@ -54,9 +57,6 @@ trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str, int prefix_type, int rowsize, int groupsize, const void *buf, size_t len, bool ascii); -struct trace_iterator; -struct trace_event; - int trace_raw_output_prep(struct trace_iterator *iter, struct trace_event *event); extern __printf(2, 3) diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h index 4a0b8c172d27..697d619aafdc 100644 --- a/include/linux/trace_seq.h +++ b/include/linux/trace_seq.h @@ -114,7 +114,11 @@ extern void trace_seq_putmem_hex(struct trace_seq *s, const void *mem, extern int trace_seq_path(struct trace_seq *s, const struct path *path); extern void trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp, - int nmaskbits); + int nmaskbits); + +extern void trace_seq_bitmask_list(struct trace_seq *s, + const unsigned long *maskp, + int nmaskbits); extern int trace_seq_hex_dump(struct trace_seq *s, const char *prefix_str, int prefix_type, int rowsize, int groupsize, @@ -137,6 +141,12 @@ trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp, { } +static inline void +trace_seq_bitmask_list(struct trace_seq *s, const unsigned long *maskp, + int nmaskbits) +{ +} + static inline int trace_print_seq(struct seq_file *m, struct trace_seq *s) { return 0; diff --git a/include/trace/stages/stage3_trace_output.h b/include/trace/stages/stage3_trace_output.h index 1e7b0bef95f5..fce85ea2df1c 100644 --- a/include/trace/stages/stage3_trace_output.h +++ b/include/trace/stages/stage3_trace_output.h @@ -39,7 +39,7 @@ void *__bitmask = __get_dynamic_array(field); \ unsigned int __bitmask_size; \ __bitmask_size = __get_dynamic_array_len(field); \ - trace_print_bitmask_seq(p, __bitmask, __bitmask_size); \ + trace_print_bitmask_seq(iter, __bitmask, __bitmask_size); \ }) #undef __get_cpumask @@ -51,7 +51,7 @@ void *__bitmask = __get_rel_dynamic_array(field); \ unsigned int __bitmask_size; \ __bitmask_size = __get_rel_dynamic_array_len(field); \ - trace_print_bitmask_seq(p, __bitmask, __bitmask_size); \ + trace_print_bitmask_seq(iter, __bitmask, __bitmask_size); \ }) #undef __get_rel_cpumask diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index b6d42fe06115..8888fc9335b6 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1411,6 +1411,7 @@ extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, C(COPY_MARKER, "copy_trace_marker"), \ C(PAUSE_ON_TRACE, "pause-on-trace"), \ C(HASH_PTR, "hash-ptr"), /* Print hashed pointer */ \ + C(BITMASK_LIST, "bitmask-list"), \ FUNCTION_FLAGS \ FGRAPH_FLAGS \ STACK_FLAGS \ diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index cc2d3306bb60..1996d7aba038 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -194,13 +194,37 @@ trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, EXPORT_SYMBOL(trace_print_symbols_seq_u64); #endif +/** + * trace_print_bitmask_seq - print a bitmask to a sequence buffer + * @iter: The trace iterator for the current event instance + * @bitmask_ptr: The pointer to the bitmask data + * @bitmask_size: The size of the bitmask in bytes + * + * Prints a bitmask into a sequence buffer as either a hex string or a + * human-readable range list, depending on the instance's "bitmask-list" + * trace option. The bitmask is formatted into the iterator's temporary + * scratchpad rather than the primary sequence buffer. This avoids + * duplication and pointer-collision issues when the returned string is + * processed by a "%s" specifier in a TP_printk() macro. + * + * Returns a pointer to the formatted string within the temporary buffer. + */ const char * -trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr, +trace_print_bitmask_seq(struct trace_iterator *iter, void *bitmask_ptr, unsigned int bitmask_size) { - const char *ret = trace_seq_buffer_ptr(p); + struct trace_seq *p = &iter->tmp_seq; + const struct trace_array *tr = iter->tr; + const char *ret; + + trace_seq_init(p); + ret = trace_seq_buffer_ptr(p); + + if (tr->trace_flags & TRACE_ITER(BITMASK_LIST)) + trace_seq_bitmask_list(p, bitmask_ptr, bitmask_size * 8); + else + trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8); - trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8); trace_seq_putc(p, 0); return ret; diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c index 32684ef4fb9d..85f6f10d107f 100644 --- a/kernel/trace/trace_seq.c +++ b/kernel/trace/trace_seq.c @@ -106,7 +106,7 @@ EXPORT_SYMBOL_GPL(trace_seq_printf); * Writes a ASCII representation of a bitmask string into @s. */ void trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp, - int nmaskbits) + int nmaskbits) { unsigned int save_len = s->seq.len; @@ -125,6 +125,33 @@ void trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp, EXPORT_SYMBOL_GPL(trace_seq_bitmask); /** + * trace_seq_bitmask_list - write a bitmask array in its list representation + * @s: trace sequence descriptor + * @maskp: points to an array of unsigned longs that represent a bitmask + * @nmaskbits: The number of bits that are valid in @maskp + * + * Writes a list representation (e.g., 0-3,5-7) of a bitmask string into @s. + */ +void trace_seq_bitmask_list(struct trace_seq *s, const unsigned long *maskp, + int nmaskbits) +{ + unsigned int save_len = s->seq.len; + + if (s->full) + return; + + __trace_seq_init(s); + + seq_buf_printf(&s->seq, "%*pbl", nmaskbits, maskp); + + if (unlikely(seq_buf_has_overflowed(&s->seq))) { + s->seq.len = save_len; + s->full = 1; + } +} +EXPORT_SYMBOL_GPL(trace_seq_bitmask_list); + +/** * trace_seq_vprintf - sequence printing of trace information * @s: trace sequence descriptor * @fmt: printf format string |