Modify all relevant *_alloc_tls functions so that they take an argument for 'init'. Setting this to 'true' will read the actual context value and store it into a thread local cache.
The function 'lttng_ust_init_thread' will use this to precalculate context values. Tracepoints can then avoid systemcalls. Signed-off-by: Norbert Lange <nolang...@gmail.com> --- * see https://lore.kernel.org/all/CADYdroN3=pae66crtsvt9ahe4t+bt61-tvhfkcuwzykhhuy...@mail.gmail.com/ * Will update docs after review, and do some more tests during the week --- src/lib/lttng-ust/lttng-context-cgroup-ns.c | 4 +++- src/lib/lttng-ust/lttng-context-ipc-ns.c | 4 +++- src/lib/lttng-ust/lttng-context-net-ns.c | 4 +++- src/lib/lttng-ust/lttng-context-procname.c | 4 +++- src/lib/lttng-ust/lttng-context-provider.c | 4 ++-- src/lib/lttng-ust/lttng-context-time-ns.c | 4 +++- src/lib/lttng-ust/lttng-context-uts-ns.c | 4 +++- src/lib/lttng-ust/lttng-context-vtid.c | 4 +++- src/lib/lttng-ust/lttng-probes.c | 4 ++-- src/lib/lttng-ust/lttng-tracer-core.h | 16 +++++++------- src/lib/lttng-ust/lttng-ust-comm.c | 24 ++++++++++----------- src/lib/lttng-ust/lttng-ust-statedump.c | 2 +- 12 files changed, 46 insertions(+), 32 deletions(-) diff --git a/src/lib/lttng-ust/lttng-context-cgroup-ns.c b/src/lib/lttng-ust/lttng-context-cgroup-ns.c index 34523ea1..3eb5ab5b 100644 --- a/src/lib/lttng-ust/lttng-context-cgroup-ns.c +++ b/src/lib/lttng-ust/lttng-context-cgroup-ns.c @@ -155,7 +155,9 @@ error_find_context: /* * Force a read (imply TLS allocation for dlopen) of TLS variables. */ -void lttng_cgroup_ns_alloc_tls(void) +void lttng_cgroup_ns_alloc_tls(bool init) { asm volatile ("" : : "m" (URCU_TLS(cached_cgroup_ns))); + if (init) + (void)get_cgroup_ns(); } diff --git a/src/lib/lttng-ust/lttng-context-ipc-ns.c b/src/lib/lttng-ust/lttng-context-ipc-ns.c index 63401e8d..b68b939f 100644 --- a/src/lib/lttng-ust/lttng-context-ipc-ns.c +++ b/src/lib/lttng-ust/lttng-context-ipc-ns.c @@ -153,7 +153,9 @@ error_find_context: /* * Force a read (imply TLS allocation for dlopen) of TLS variables. */ -void lttng_ipc_ns_alloc_tls(void) +void lttng_ipc_ns_alloc_tls(bool init) { asm volatile ("" : : "m" (URCU_TLS(cached_ipc_ns))); + if (init) + (void)get_ipc_ns(); } diff --git a/src/lib/lttng-ust/lttng-context-net-ns.c b/src/lib/lttng-ust/lttng-context-net-ns.c index 960591c2..93e574ad 100644 --- a/src/lib/lttng-ust/lttng-context-net-ns.c +++ b/src/lib/lttng-ust/lttng-context-net-ns.c @@ -153,7 +153,9 @@ error_find_context: /* * Force a read (imply TLS allocation for dlopen) of TLS variables. */ -void lttng_net_ns_alloc_tls(void) +void lttng_net_ns_alloc_tls(bool init) { asm volatile ("" : : "m" (URCU_TLS(cached_net_ns))); + if (init) + (void)get_net_ns(); } diff --git a/src/lib/lttng-ust/lttng-context-procname.c b/src/lib/lttng-ust/lttng-context-procname.c index b5bf77be..95f6fe42 100644 --- a/src/lib/lttng-ust/lttng-context-procname.c +++ b/src/lib/lttng-ust/lttng-context-procname.c @@ -122,7 +122,9 @@ error_find_context: /* * Force a read (imply TLS allocation for dlopen) of TLS variables. */ -void lttng_procname_alloc_tls(void) +void lttng_procname_alloc_tls(bool init) { asm volatile ("" : : "m" (URCU_TLS(cached_procname)[0])); + if (init) + (void)wrapper_getprocname(); } diff --git a/src/lib/lttng-ust/lttng-context-provider.c b/src/lib/lttng-ust/lttng-context-provider.c index 4e7e429f..ba24aad7 100644 --- a/src/lib/lttng-ust/lttng-context-provider.c +++ b/src/lib/lttng-ust/lttng-context-provider.c @@ -67,7 +67,7 @@ struct lttng_ust_registered_context_provider *lttng_ust_context_provider_registe size_t name_len = strlen(provider->name); uint32_t hash; - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(false); /* Provider name starts with "$app.". */ if (strncmp("$app.", provider->name, strlen("$app.")) != 0) @@ -101,7 +101,7 @@ end: void lttng_ust_context_provider_unregister(struct lttng_ust_registered_context_provider *reg_provider) { - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(false); if (ust_lock()) goto end; diff --git a/src/lib/lttng-ust/lttng-context-time-ns.c b/src/lib/lttng-ust/lttng-context-time-ns.c index ec32a1de..a957409b 100644 --- a/src/lib/lttng-ust/lttng-context-time-ns.c +++ b/src/lib/lttng-ust/lttng-context-time-ns.c @@ -152,7 +152,9 @@ error_find_context: /* * Force a read (imply TLS allocation for dlopen) of TLS variables. */ -void lttng_time_ns_alloc_tls(void) +void lttng_time_ns_alloc_tls(bool init) { asm volatile ("" : : "m" (URCU_TLS(cached_time_ns))); + if (init) + (void)get_time_ns(); } diff --git a/src/lib/lttng-ust/lttng-context-uts-ns.c b/src/lib/lttng-ust/lttng-context-uts-ns.c index 06a978fd..0c802188 100644 --- a/src/lib/lttng-ust/lttng-context-uts-ns.c +++ b/src/lib/lttng-ust/lttng-context-uts-ns.c @@ -154,7 +154,9 @@ error_find_context: /* * Force a read (imply TLS allocation for dlopen) of TLS variables. */ -void lttng_uts_ns_alloc_tls(void) +void lttng_uts_ns_alloc_tls(bool init) { asm volatile ("" : : "m" (URCU_TLS(cached_uts_ns))); + if (init) + (void)get_uts_ns(); } diff --git a/src/lib/lttng-ust/lttng-context-vtid.c b/src/lib/lttng-ust/lttng-context-vtid.c index 880e34b9..d3c9863e 100644 --- a/src/lib/lttng-ust/lttng-context-vtid.c +++ b/src/lib/lttng-ust/lttng-context-vtid.c @@ -112,7 +112,9 @@ error_find_context: /* * Force a read (imply TLS allocation for dlopen) of TLS variables. */ -void lttng_vtid_alloc_tls(void) +void lttng_vtid_alloc_tls(bool init) { asm volatile ("" : : "m" (URCU_TLS(cached_vtid))); + if (init) + (void)wrapper_getvtid(); } diff --git a/src/lib/lttng-ust/lttng-probes.c b/src/lib/lttng-ust/lttng-probes.c index e8e08ff1..314cb7a0 100644 --- a/src/lib/lttng-ust/lttng-probes.c +++ b/src/lib/lttng-ust/lttng-probes.c @@ -231,7 +231,7 @@ struct lttng_ust_registered_probe *lttng_ust_probe_register(const struct lttng_u { struct lttng_ust_registered_probe *reg_probe = NULL; - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(false); /* * If version mismatch, don't register, but don't trigger assert @@ -269,7 +269,7 @@ end: void lttng_ust_probe_unregister(struct lttng_ust_registered_probe *reg_probe) { - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(false); if (!reg_probe) return; diff --git a/src/lib/lttng-ust/lttng-tracer-core.h b/src/lib/lttng-ust/lttng-tracer-core.h index eadc43ed..dbb3bd9f 100644 --- a/src/lib/lttng-ust/lttng-tracer-core.h +++ b/src/lib/lttng-ust/lttng-tracer-core.h @@ -34,28 +34,28 @@ void ust_lock_nocheck(void) void ust_unlock(void) __attribute__((visibility("hidden"))); -void lttng_ust_alloc_tls(void) +void lttng_ust_alloc_tls(bool init) __attribute__((visibility("hidden"))); -void lttng_vtid_alloc_tls(void) +void lttng_vtid_alloc_tls(bool init) __attribute__((visibility("hidden"))); -void lttng_procname_alloc_tls(void) +void lttng_procname_alloc_tls(bool init) __attribute__((visibility("hidden"))); -void lttng_cgroup_ns_alloc_tls(void) +void lttng_cgroup_ns_alloc_tls(bool init) __attribute__((visibility("hidden"))); -void lttng_ipc_ns_alloc_tls(void) +void lttng_ipc_ns_alloc_tls(bool init) __attribute__((visibility("hidden"))); -void lttng_net_ns_alloc_tls(void) +void lttng_net_ns_alloc_tls(bool init) __attribute__((visibility("hidden"))); -void lttng_time_ns_alloc_tls(void) +void lttng_time_ns_alloc_tls(bool init) __attribute__((visibility("hidden"))); -void lttng_uts_ns_alloc_tls(void) +void lttng_uts_ns_alloc_tls(bool init) __attribute__((visibility("hidden"))); const char *lttng_ust_obj_get_name(int id) diff --git a/src/lib/lttng-ust/lttng-ust-comm.c b/src/lib/lttng-ust/lttng-ust-comm.c index 7f34efe7..ba0bd985 100644 --- a/src/lib/lttng-ust/lttng-ust-comm.c +++ b/src/lib/lttng-ust/lttng-ust-comm.c @@ -407,21 +407,21 @@ void lttng_lttng_ust_urcu_alloc_tls(void) (void) lttng_ust_urcu_read_ongoing(); } -void lttng_ust_alloc_tls(void) +void lttng_ust_alloc_tls(bool init) { lttng_lttng_ust_urcu_alloc_tls(); lttng_ringbuffer_alloc_tls(); - lttng_vtid_alloc_tls(); + lttng_vtid_alloc_tls(init); lttng_nest_count_alloc_tls(); - lttng_procname_alloc_tls(); + lttng_procname_alloc_tls(init); lttng_ust_mutex_nest_alloc_tls(); lttng_ust_perf_counter_alloc_tls(); lttng_ust_common_alloc_tls(); - lttng_cgroup_ns_alloc_tls(); - lttng_ipc_ns_alloc_tls(); - lttng_net_ns_alloc_tls(); - lttng_time_ns_alloc_tls(); - lttng_uts_ns_alloc_tls(); + lttng_cgroup_ns_alloc_tls(init); + lttng_ipc_ns_alloc_tls(init); + lttng_net_ns_alloc_tls(init); + lttng_time_ns_alloc_tls(init); + lttng_uts_ns_alloc_tls(init); lttng_ust_ring_buffer_client_discard_alloc_tls(); lttng_ust_ring_buffer_client_discard_rt_alloc_tls(); lttng_ust_ring_buffer_client_overwrite_alloc_tls(); @@ -446,7 +446,7 @@ void lttng_ust_init_thread(void) * ensure those are initialized before a signal handler nesting over * this thread attempts to use them. */ - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(true); } int lttng_get_notify_socket(void *owner) @@ -1815,7 +1815,7 @@ void *ust_listener_thread(void *arg) int sock, ret, prev_connect_failed = 0, has_waited = 0, fd; long timeout; - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(false); /* * If available, add '-ust' to the end of this thread's * process name @@ -2183,7 +2183,7 @@ void lttng_ust_ctor(void) * to be the dynamic linker mutex) and ust_lock, taken within * the ust lock. */ - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(false); lttng_ust_loaded = 1; @@ -2497,7 +2497,7 @@ void lttng_ust_before_fork(sigset_t *save_sigset) int ret; /* Allocate lttng-ust TLS. */ - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(false); if (URCU_TLS(lttng_ust_nest_count)) return; diff --git a/src/lib/lttng-ust/lttng-ust-statedump.c b/src/lib/lttng-ust/lttng-ust-statedump.c index 309a98fa..ee180a0d 100644 --- a/src/lib/lttng-ust/lttng-ust-statedump.c +++ b/src/lib/lttng-ust/lttng-ust-statedump.c @@ -557,7 +557,7 @@ void lttng_ust_dl_update(void *ip) * Force the allocation of lttng-ust TLS variables when called from * dlopen/dlclose instrumentation. */ - lttng_ust_alloc_tls(); + lttng_ust_alloc_tls(false); data.exec_found = 0; data.first = true; -- 2.35.1 _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
