On Tue, May 5, 2020 at 9:33 AM Jerin Jacob <jerinjac...@gmail.com> wrote: > > > What the proposed patch here. > > > # Making N constructors from one > > > # Grouping global variable and register function under a single Marco > > > and making it as N constructors. > > > Why can we do the same logic for rte_log? > > > > rte_log is simple, there is nothing to simplify. > > Why not make, rte_log_register() and the global variable under a macro? > That's something done by the proposed patch.
At the moment, there is not much that would go into such a macro, but I had started to do some cleanups on logtype registration. I did not finish because the question of the default log level is still unclear (and I did not take the time). Having the logtype definition as part of the macro would be fine to me. https://patchwork.dpdk.org/patch/57743/ > > > > rte_trace requires 3 macros calls per trace type: > > > > RTE_TRACE_POINT_REGISTER, RTE_TRACE_POINT_DEFINE, RTE_TRACE_POINT_ARGS > > > > This patch is unifying the first 2 macro calls to make usage simpler, > > > > and ease rte_trace adoption. > > > > > > RTE_TRACE_POINT_ARGS is NOP and for the syntax. > > > It is similar to rte_log. rte_log don't have RTE_TRACE_POINT_REGISTER > > > instead > > > it is creating global variable see, "int otx2_logtype_base; > > > > > > > > > > > Note: the other usability weirdness is mandating declaring each trace > > > > function with a magic double underscore prefix which appears nowhere > > > > else. > > > > > > > > > > > > > Analyze the impact wrt boot time and cross-platform pov as the log > > > > > has a lot of entries to test. If the usage makes sense then it should > > > > > make sense > > > > > for rte_log too. I would like to NOT have trace to be the first > > > > > library to explode > > > > > with the constructor scheme. I suggest removing this specific patch > > > > > from RC2 and > > > > > revisit later. > > > > > > > > You still did not give any argument against increasing the number > > > > of constructors. > > > > > > If you are proposing the new scheme, you have to prove the overhead > > > with a significant number of constructors > > > and why it has differed from existing scheme of things. That's is the > > > norm in opensource. > > > > I say there is no overhead. > > Please share the data. Measured time between first rte_trace_point_register and last one with a simple patch: diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c index 875553d7e..95618314b 100644 --- a/lib/librte_eal/common/eal_common_trace.c +++ b/lib/librte_eal/common/eal_common_trace.c @@ -8,6 +8,7 @@ #include <regex.h> #include <rte_common.h> +#include <rte_cycles.h> #include <rte_errno.h> #include <rte_lcore.h> #include <rte_per_lcore.h> @@ -23,6 +24,9 @@ static RTE_DEFINE_PER_LCORE(int, ctf_count); static struct trace_point_head tp_list = STAILQ_HEAD_INITIALIZER(tp_list); static struct trace trace = { .args = STAILQ_HEAD_INITIALIZER(trace.args), }; +uint64_t first_register; +uint64_t last_register; + struct trace * trace_obj_get(void) { @@ -43,6 +47,8 @@ eal_trace_init(void) /* Trace memory should start with 8B aligned for natural alignment */ RTE_BUILD_BUG_ON((offsetof(struct __rte_trace_header, mem) % 8) != 0); + trace_err("delta=%"PRIu64, last_register - first_register); + /* One of the trace point registration failed */ if (trace.register_errno) { rte_errno = trace.register_errno; @@ -425,6 +431,9 @@ __rte_trace_point_register(rte_trace_point_t *handle, const char *name, goto fail; } + if (first_register == 0) + first_register = rte_get_tsc_cycles(); + /* Check the size of the trace point object */ RTE_PER_LCORE(trace_point_sz) = 0; RTE_PER_LCORE(ctf_count) = 0; @@ -486,6 +495,8 @@ __rte_trace_point_register(rte_trace_point_t *handle, const char *name, STAILQ_INSERT_TAIL(&tp_list, tp, next); __atomic_thread_fence(__ATOMIC_RELEASE); + last_register = rte_get_tsc_cycles(); + /* All Good !!! */ return 0; free: I started testpmd 100 times for static and shared gcc builds (test-meson-builds.sh) on a system with a 2.6GHz xeon. v20.05-rc1-13-g08dd97130 (before patch): static: count=100, min=580812, max=1482326, avg=1764932 shared: count=100, min=554648, max=1344163, avg=1704638 v20.05-rc1-14-g44250f392 (after patch): static: count=100, min=668273, max=1530330, avg=1682548 shared: count=100, min=554634, max=1330264, avg=1672398 -- David Marchand
