alistair23-linux/kernel/trace/trace_entries.h
Steven Rostedt (Red Hat) 7b2c862501 tracing: Add NMI tracing in hwlat detector
As NMIs can also cause latency when interrupts are disabled, the hwlat
detectory has no way to know if the latency it detects is from an NMI or an
SMI or some other hardware glitch.

As ftrace_nmi_enter/exit() funtions are no longer used (except for sh, which
isn't supported anymore), I converted those to "arch_ftrace_nmi_enter/exit"
and use ftrace_nmi_enter/exit() to check if hwlat detector is tracing or
not, and if so, it calls into the hwlat utility.

Since the hwlat detector only has a single kthread that is spinning with
interrupts disabled, it marks what CPU it is on, and if the NMI callback
happens on that CPU, it records the time spent in that NMI. This is added to
the output that is generated by the hwlat detector as:

 #3     inner/outer(us):    9/9     ts:1470836488.206734548
 #4     inner/outer(us):    0/8     ts:1470836497.140808588
 #5     inner/outer(us):    0/6     ts:1470836499.140825168 nmi-total:5 nmi-count:1
 #6     inner/outer(us):    9/9     ts:1470836501.140841748

All time is still tracked in microseconds.

The NMI information is only shown when an NMI occurred during the sample.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-09-02 12:47:55 -04:00

352 lines
8 KiB
C

/*
* This file defines the trace event structures that go into the ring
* buffer directly. They are created via macros so that changes for them
* appear in the format file. Using macros will automate this process.
*
* The macro used to create a ftrace data structure is:
*
* FTRACE_ENTRY( name, struct_name, id, structure, print )
*
* @name: the name used the event name, as well as the name of
* the directory that holds the format file.
*
* @struct_name: the name of the structure that is created.
*
* @id: The event identifier that is used to detect what event
* this is from the ring buffer.
*
* @structure: the structure layout
*
* - __field( type, item )
* This is equivalent to declaring
* type item;
* in the structure.
* - __array( type, item, size )
* This is equivalent to declaring
* type item[size];
* in the structure.
*
* * for structures within structures, the format of the internal
* structure is laid out. This allows the internal structure
* to be deciphered for the format file. Although these macros
* may become out of sync with the internal structure, they
* will create a compile error if it happens. Since the
* internel structures are just tracing helpers, this is not
* an issue.
*
* When an internal structure is used, it should use:
*
* __field_struct( type, item )
*
* instead of __field. This will prevent it from being shown in
* the output file. The fields in the structure should use.
*
* __field_desc( type, container, item )
* __array_desc( type, container, item, len )
*
* type, item and len are the same as __field and __array, but
* container is added. This is the name of the item in
* __field_struct that this is describing.
*
*
* @print: the print format shown to users in the format file.
*/
/*
* Function trace entry - function address and parent function address:
*/
FTRACE_ENTRY_REG(function, ftrace_entry,
TRACE_FN,
F_STRUCT(
__field( unsigned long, ip )
__field( unsigned long, parent_ip )
),
F_printk(" %lx <-- %lx", __entry->ip, __entry->parent_ip),
FILTER_TRACE_FN,
perf_ftrace_event_register
);
/* Function call entry */
FTRACE_ENTRY_PACKED(funcgraph_entry, ftrace_graph_ent_entry,
TRACE_GRAPH_ENT,
F_STRUCT(
__field_struct( struct ftrace_graph_ent, graph_ent )
__field_desc( unsigned long, graph_ent, func )
__field_desc( int, graph_ent, depth )
),
F_printk("--> %lx (%d)", __entry->func, __entry->depth),
FILTER_OTHER
);
/* Function return entry */
FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
TRACE_GRAPH_RET,
F_STRUCT(
__field_struct( struct ftrace_graph_ret, ret )
__field_desc( unsigned long, ret, func )
__field_desc( unsigned long long, ret, calltime)
__field_desc( unsigned long long, ret, rettime )
__field_desc( unsigned long, ret, overrun )
__field_desc( int, ret, depth )
),
F_printk("<-- %lx (%d) (start: %llx end: %llx) over: %d",
__entry->func, __entry->depth,
__entry->calltime, __entry->rettime,
__entry->depth),
FILTER_OTHER
);
/*
* Context switch trace entry - which task (and prio) we switched from/to:
*
* This is used for both wakeup and context switches. We only want
* to create one structure, but we need two outputs for it.
*/
#define FTRACE_CTX_FIELDS \
__field( unsigned int, prev_pid ) \
__field( unsigned int, next_pid ) \
__field( unsigned int, next_cpu ) \
__field( unsigned char, prev_prio ) \
__field( unsigned char, prev_state ) \
__field( unsigned char, next_prio ) \
__field( unsigned char, next_state )
FTRACE_ENTRY(context_switch, ctx_switch_entry,
TRACE_CTX,
F_STRUCT(
FTRACE_CTX_FIELDS
),
F_printk("%u:%u:%u ==> %u:%u:%u [%03u]",
__entry->prev_pid, __entry->prev_prio, __entry->prev_state,
__entry->next_pid, __entry->next_prio, __entry->next_state,
__entry->next_cpu),
FILTER_OTHER
);
/*
* FTRACE_ENTRY_DUP only creates the format file, it will not
* create another structure.
*/
FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry,
TRACE_WAKE,
F_STRUCT(
FTRACE_CTX_FIELDS
),
F_printk("%u:%u:%u ==+ %u:%u:%u [%03u]",
__entry->prev_pid, __entry->prev_prio, __entry->prev_state,
__entry->next_pid, __entry->next_prio, __entry->next_state,
__entry->next_cpu),
FILTER_OTHER
);
/*
* Stack-trace entry:
*/
#define FTRACE_STACK_ENTRIES 8
#ifndef CONFIG_64BIT
# define IP_FMT "%08lx"
#else
# define IP_FMT "%016lx"
#endif
FTRACE_ENTRY(kernel_stack, stack_entry,
TRACE_STACK,
F_STRUCT(
__field( int, size )
__dynamic_array(unsigned long, caller )
),
F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
"\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
"\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n",
__entry->caller[0], __entry->caller[1], __entry->caller[2],
__entry->caller[3], __entry->caller[4], __entry->caller[5],
__entry->caller[6], __entry->caller[7]),
FILTER_OTHER
);
FTRACE_ENTRY(user_stack, userstack_entry,
TRACE_USER_STACK,
F_STRUCT(
__field( unsigned int, tgid )
__array( unsigned long, caller, FTRACE_STACK_ENTRIES )
),
F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
"\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
"\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n",
__entry->caller[0], __entry->caller[1], __entry->caller[2],
__entry->caller[3], __entry->caller[4], __entry->caller[5],
__entry->caller[6], __entry->caller[7]),
FILTER_OTHER
);
/*
* trace_printk entry:
*/
FTRACE_ENTRY(bprint, bprint_entry,
TRACE_BPRINT,
F_STRUCT(
__field( unsigned long, ip )
__field( const char *, fmt )
__dynamic_array( u32, buf )
),
F_printk("%ps: %s",
(void *)__entry->ip, __entry->fmt),
FILTER_OTHER
);
FTRACE_ENTRY(print, print_entry,
TRACE_PRINT,
F_STRUCT(
__field( unsigned long, ip )
__dynamic_array( char, buf )
),
F_printk("%ps: %s",
(void *)__entry->ip, __entry->buf),
FILTER_OTHER
);
FTRACE_ENTRY(bputs, bputs_entry,
TRACE_BPUTS,
F_STRUCT(
__field( unsigned long, ip )
__field( const char *, str )
),
F_printk("%ps: %s",
(void *)__entry->ip, __entry->str),
FILTER_OTHER
);
FTRACE_ENTRY(mmiotrace_rw, trace_mmiotrace_rw,
TRACE_MMIO_RW,
F_STRUCT(
__field_struct( struct mmiotrace_rw, rw )
__field_desc( resource_size_t, rw, phys )
__field_desc( unsigned long, rw, value )
__field_desc( unsigned long, rw, pc )
__field_desc( int, rw, map_id )
__field_desc( unsigned char, rw, opcode )
__field_desc( unsigned char, rw, width )
),
F_printk("%lx %lx %lx %d %x %x",
(unsigned long)__entry->phys, __entry->value, __entry->pc,
__entry->map_id, __entry->opcode, __entry->width),
FILTER_OTHER
);
FTRACE_ENTRY(mmiotrace_map, trace_mmiotrace_map,
TRACE_MMIO_MAP,
F_STRUCT(
__field_struct( struct mmiotrace_map, map )
__field_desc( resource_size_t, map, phys )
__field_desc( unsigned long, map, virt )
__field_desc( unsigned long, map, len )
__field_desc( int, map, map_id )
__field_desc( unsigned char, map, opcode )
),
F_printk("%lx %lx %lx %d %x",
(unsigned long)__entry->phys, __entry->virt, __entry->len,
__entry->map_id, __entry->opcode),
FILTER_OTHER
);
#define TRACE_FUNC_SIZE 30
#define TRACE_FILE_SIZE 20
FTRACE_ENTRY(branch, trace_branch,
TRACE_BRANCH,
F_STRUCT(
__field( unsigned int, line )
__array( char, func, TRACE_FUNC_SIZE+1 )
__array( char, file, TRACE_FILE_SIZE+1 )
__field( char, correct )
),
F_printk("%u:%s:%s (%u)",
__entry->line,
__entry->func, __entry->file, __entry->correct),
FILTER_OTHER
);
FTRACE_ENTRY(hwlat, hwlat_entry,
TRACE_HWLAT,
F_STRUCT(
__field( u64, duration )
__field( u64, outer_duration )
__field( u64, nmi_total_ts )
__field_struct( struct timespec, timestamp )
__field_desc( long, timestamp, tv_sec )
__field_desc( long, timestamp, tv_nsec )
__field( unsigned int, nmi_count )
__field( unsigned int, seqnum )
),
F_printk("cnt:%u\tts:%010lu.%010lu\tinner:%llu\touter:%llunmi-ts:%llu\tnmi-count:%u\n",
__entry->seqnum,
__entry->tv_sec,
__entry->tv_nsec,
__entry->duration,
__entry->outer_duration,
__entry->nmi_total_ts,
__entry->nmi_count),
FILTER_OTHER
);