Re: [dpdk-dev] [PATCH v1 12/32] eal/trace: implement registration payload

["Mattias Rönnblom" <mattias.ronnblom@ericsson.com>]

On 2020-03-18 20:02, jerinj@marvell.com wrote:
> From: Jerin Jacob <jerinj@marvell.com>
>
> The trace function payloads such as rte_trace_ctf_* have
> dual functions. The first to emit the payload for the registration
> function and the second one to act as trace memory emitters.
>
> When it used as registration payload, it will do the following to
> fulfill the registration job.
> - Find out the size of the event
> - Generate metadata field string using __rte_trace_emit_ctf_field().
>
> Signed-off-by: Jerin Jacob <jerinj@marvell.com>
> Signed-off-by: Sunil Kumar Kori <skori@marvell.com>
> ---
>   lib/librte_eal/common/eal_common_trace.c      | 19 +++++++
>   lib/librte_eal/common/include/rte_trace.h     | 20 ++++++++
>   .../common/include/rte_trace_register.h       | 50 +++++++++++++++++++
>   lib/librte_eal/rte_eal_version.map            |  2 +
>   4 files changed, 91 insertions(+)
>
> diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
> index 6cb724080..94d3da0d3 100644
> --- a/lib/librte_eal/common/eal_common_trace.c
> +++ b/lib/librte_eal/common/eal_common_trace.c
> @@ -493,6 +493,25 @@ trace_mem_per_thread_free(void)
>   	rte_spinlock_unlock(&trace->lock);
>   }
>   
> +void
> +__rte_trace_emit_ctf_field(size_t sz, const char *in, const char *datatype)
> +{
> +	char *field = RTE_PER_LCORE(ctf_field);
> +	int count = RTE_PER_LCORE(ctf_count);
> +	int rc;
> +
> +	RTE_PER_LCORE(trace_point_sz) += sz;
> +	rc = snprintf(RTE_PTR_ADD(field, count),
> +		      RTE_MAX(0, TRACE_CTF_FIELD_SIZE - 1 - count),
> +		      "%s %s;", datatype, in);
> +	if (rc <= 0) {
> +		RTE_PER_LCORE(trace_point_sz) = 0;
> +		trace_crit("CTF field is too long");
> +		return;
> +	}
> +	RTE_PER_LCORE(ctf_count) += rc;
> +}
> +
>   int
>   __rte_trace_point_register(rte_trace_t handle, const char *name, uint32_t level,
>   			 void (*fn)(void))
> diff --git a/lib/librte_eal/common/include/rte_trace.h b/lib/librte_eal/common/include/rte_trace.h
> index 358b1b7ca..c24fe8d66 100644
> --- a/lib/librte_eal/common/include/rte_trace.h
> +++ b/lib/librte_eal/common/include/rte_trace.h
> @@ -520,6 +520,8 @@ _tp _args \
>   
>   /** @internal Macro to define maximum emit length of string datatype. */
>   #define __RTE_TRACE_EMIT_STRING_LEN_MAX 32
> +/** @internal Macro to define event header size. */
> +#define __RTE_TRACE_EVENT_HEADER_SZ sizeof(uint64_t)
>   
>   /**
>    * @internal @warning
> @@ -553,6 +555,24 @@ void __rte_trace_mem_per_thread_alloc(void);
>   __rte_experimental
>   int __rte_trace_point_register(rte_trace_t trace, const char *name,
>   			     uint32_t level, void (*fn)(void));
> +/**
> + * @internal @warning
> + * @b EXPERIMENTAL: this API may change without prior notice
> + *
> + * Helper function to emit ctf field.
> + *
> + * @param sz
> + *   The tracepoint size.
> + * @param field
> + *   The name of the trace event.
> + * @param type
> + *   The datatype of the trace event as string.
> + * @return
> + *   - 0: Success.
> + *   - <0: Failure.
> + */
> +__rte_experimental
> +void __rte_trace_emit_ctf_field(size_t sz, const char *field, const char *type);
>   
>   #ifdef RTE_TRACE_POINT_REGISTER_SELECT
>   #include <rte_trace_register.h>
> diff --git a/lib/librte_eal/common/include/rte_trace_register.h b/lib/librte_eal/common/include/rte_trace_register.h
> index e9940b414..93d6396df 100644
> --- a/lib/librte_eal/common/include/rte_trace_register.h
> +++ b/lib/librte_eal/common/include/rte_trace_register.h
> @@ -10,6 +10,7 @@
>   #define _RTE_TRACE_REGISTER_H_
>   
>   #include <rte_per_lcore.h>
> +#include <rte_log.h>
>   
>   RTE_DECLARE_PER_LCORE(volatile int, trace_point_sz);
>   
> @@ -17,4 +18,53 @@ RTE_DECLARE_PER_LCORE(volatile int, trace_point_sz);
>   	__rte_trace_point_register(&__##trace, RTE_STR(name),\
>   			RTE_LOG_ ## level, (void (*)(void)) trace)
>   
> +#define __rte_trace_emit_header_generic(t)\
> +	RTE_PER_LCORE(trace_point_sz) = __RTE_TRACE_EVENT_HEADER_SZ
> +
> +#define __rte_trace_emit_header_dp(t) __rte_trace_emit_header_generic(t)
> +
> +#define rte_trace_ctf_u64(in)\
> +	RTE_BUILD_BUG_ON(sizeof(uint64_t) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(uint64_t), RTE_STR(in), "uint64_t")

Delegate to a generic macro, to which you pass the type and the "in" 
parameter.

> +#define rte_trace_ctf_i64(in)\
> +	RTE_BUILD_BUG_ON(sizeof(int64_t) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(int64_t), RTE_STR(in), "int64_t")
> +#define rte_trace_ctf_u32(in)\
> +	RTE_BUILD_BUG_ON(sizeof(uint32_t) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(uint32_t), RTE_STR(in), "uint32_t")
> +#define rte_trace_ctf_i32(in)\
> +	RTE_BUILD_BUG_ON(sizeof(int32_t) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(int32_t), RTE_STR(in), "int32_t")
> +#define rte_trace_ctf_u16(in)\
> +	RTE_BUILD_BUG_ON(sizeof(uint16_t) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(uint16_t), RTE_STR(in), "uint16_t")
> +#define rte_trace_ctf_i16(in)\
> +	RTE_BUILD_BUG_ON(sizeof(int16_t) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(int16_t), RTE_STR(in), "int16_t")
> +#define rte_trace_ctf_u8(in)\
> +	RTE_BUILD_BUG_ON(sizeof(uint8_t) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(uint8_t), RTE_STR(in), "uint8_t")
> +#define rte_trace_ctf_i8(in)\
> +	RTE_BUILD_BUG_ON(sizeof(int8_t) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(int8_t), RTE_STR(in), "int8_t")
> +#define rte_trace_ctf_int(in)\
> +	RTE_BUILD_BUG_ON(sizeof(int) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(int), RTE_STR(in), "int32_t")
> +#define rte_trace_ctf_long(in)\
> +	RTE_BUILD_BUG_ON(sizeof(long) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(long), RTE_STR(in), "long")
> +#define rte_trace_ctf_float(in)\
> +	RTE_BUILD_BUG_ON(sizeof(float) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(float), RTE_STR(in), "float")
> +#define rte_trace_ctf_double(in)\
> +	RTE_BUILD_BUG_ON(sizeof(double) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(double), RTE_STR(in), "double")
> +#define rte_trace_ctf_ptr(in)\
> +	RTE_BUILD_BUG_ON(sizeof(void *) != sizeof(typeof(in)));\
> +	__rte_trace_emit_ctf_field(sizeof(void *), RTE_STR(in), "uintptr_t")
> +#define rte_trace_ctf_string(in)\
> +	RTE_SET_USED(in);\
> +	__rte_trace_emit_ctf_field(__RTE_TRACE_EMIT_STRING_LEN_MAX,\
> +				   RTE_STR(in)"[32]", "string_bounded_t")
> +
>   #endif /* _RTE_TRACE_REGISTER_H_ */
> diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
> index f56d1867e..0c787302f 100644
> --- a/lib/librte_eal/rte_eal_version.map
> +++ b/lib/librte_eal/rte_eal_version.map
> @@ -339,7 +339,9 @@ EXPERIMENTAL {
>   	# added in 20.05
>   	rte_thread_getname;
>   	__rte_trace_mem_per_thread_alloc;
> +	__rte_trace_emit_ctf_field;
>   	__rte_trace_point_register;
> +	per_lcore_trace_point_sz;
>   	per_lcore_trace_mem;
>   	rte_trace_global_is_enabled;
>   	rte_trace_global_is_disabled;