From 53b9d7db85d4fafa5b8044a474bb84b8d80966ad Mon Sep 17 00:00:00 2001 From: Francis Deslauriers Date: Fri, 29 Nov 2019 16:35:01 -0500 Subject: [PATCH] Decouple `struct lttng_event` from filter code The filter infrastructure will be used by event notifiers and decoupling this will allow for massive code reuse. Of all `struct lttng_event`'s fields, filter code needs: 1. The `const struct lttng_event_desc *desc` field, 2. The `struct cds_list_head bytecode_runtime_head` list. These fields are used to do the tracepoint field relocation (`apply_field_reloc()` and `specialize_event_payload_lookup()`). Given that only these two fields are needed, we can pass them directly to these functions. Signed-off-by: Francis Deslauriers Signed-off-by: Mathieu Desnoyers Change-Id: I25cb6fba5ba3cb74dbc4ee9f1fa1026171a6599a --- liblttng-ust/lttng-events.c | 5 ++- liblttng-ust/lttng-filter-specialize.c | 11 +++-- liblttng-ust/lttng-filter.c | 60 +++++++++++++------------- liblttng-ust/lttng-filter.h | 2 +- liblttng-ust/ust-events-internal.h | 6 ++- 5 files changed, 43 insertions(+), 41 deletions(-) diff --git a/liblttng-ust/lttng-events.c b/liblttng-ust/lttng-events.c index 0c684df2..02e6704e 100644 --- a/liblttng-ust/lttng-events.c +++ b/liblttng-ust/lttng-events.c @@ -977,7 +977,10 @@ int lttng_event_enabler_ref_events(struct lttng_event_enabler *event_enabler) /* * Link filter bytecodes if not linked yet. */ - lttng_event_enabler_link_bytecode(event, event_enabler); + lttng_enabler_link_bytecode(event->desc, + &session->ctx, + &event->bytecode_runtime_head, + lttng_event_enabler_as_enabler(event_enabler)); /* TODO: merge event context. */ } diff --git a/liblttng-ust/lttng-filter-specialize.c b/liblttng-ust/lttng-filter-specialize.c index d4f8a957..b7ab6158 100644 --- a/liblttng-ust/lttng-filter-specialize.c +++ b/liblttng-ust/lttng-filter-specialize.c @@ -599,14 +599,13 @@ end: return ret; } -static int specialize_event_payload_lookup(struct lttng_event *event, +static int specialize_payload_lookup(const struct lttng_event_desc *event_desc, struct bytecode_runtime *runtime, struct load_op *insn, struct vstack_load *load) { const char *name; uint16_t offset; - const struct lttng_event_desc *desc = event->desc; unsigned int i, nr_fields; bool found = false; uint32_t field_offset = 0; @@ -615,11 +614,11 @@ static int specialize_event_payload_lookup(struct lttng_event *event, struct filter_get_index_data gid; ssize_t data_offset; - nr_fields = desc->nr_fields; + nr_fields = event_desc->nr_fields; offset = ((struct get_symbol *) insn->data)->offset; name = runtime->p.bc->bc.data + runtime->p.bc->bc.reloc_offset + offset; for (i = 0; i < nr_fields; i++) { - field = &desc->fields[i]; + field = &event_desc->fields[i]; if (field->u.ext.nofilter) { continue; } @@ -678,7 +677,7 @@ end: return ret; } -int lttng_filter_specialize_bytecode(struct lttng_event *event, +int lttng_filter_specialize_bytecode(const struct lttng_event_desc *event_desc, struct bytecode_runtime *bytecode) { void *pc, *next_pc, *start_pc; @@ -1428,7 +1427,7 @@ int lttng_filter_specialize_bytecode(struct lttng_event *event, break; case LOAD_ROOT_PAYLOAD: /* Lookup event payload field. */ - ret = specialize_event_payload_lookup(event, + ret = specialize_payload_lookup(event_desc, bytecode, insn, &vstack_ax(stack)->load); if (ret) diff --git a/liblttng-ust/lttng-filter.c b/liblttng-ust/lttng-filter.c index e9774b48..5ee12d26 100644 --- a/liblttng-ust/lttng-filter.c +++ b/liblttng-ust/lttng-filter.c @@ -188,14 +188,13 @@ const char *print_op(enum filter_op op) } static -int apply_field_reloc(struct lttng_event *event, +int apply_field_reloc(const struct lttng_event_desc *event_desc, struct bytecode_runtime *runtime, uint32_t runtime_len, uint32_t reloc_offset, const char *field_name, enum filter_op filter_op) { - const struct lttng_event_desc *desc; const struct lttng_event_field *fields, *field = NULL; unsigned int nr_fields, i; struct load_op *op; @@ -204,13 +203,12 @@ int apply_field_reloc(struct lttng_event *event, dbg_printf("Apply field reloc: %u %s\n", reloc_offset, field_name); /* Lookup event by name */ - desc = event->desc; - if (!desc) + if (!event_desc) return -EINVAL; - fields = desc->fields; + fields = event_desc->fields; if (!fields) return -EINVAL; - nr_fields = desc->nr_fields; + nr_fields = event_desc->nr_fields; for (i = 0; i < nr_fields; i++) { if (fields[i].u.ext.nofilter) { continue; @@ -291,8 +289,7 @@ int apply_field_reloc(struct lttng_event *event, } static -int apply_context_reloc(struct lttng_event *event, - struct bytecode_runtime *runtime, +int apply_context_reloc(struct bytecode_runtime *runtime, uint32_t runtime_len, uint32_t reloc_offset, const char *context_name, @@ -370,7 +367,7 @@ int apply_context_reloc(struct lttng_event *event, } static -int apply_reloc(struct lttng_event *event, +int apply_reloc(const struct lttng_event_desc *event_desc, struct bytecode_runtime *runtime, uint32_t runtime_len, uint32_t reloc_offset, @@ -387,10 +384,10 @@ int apply_reloc(struct lttng_event *event, op = (struct load_op *) &runtime->code[reloc_offset]; switch (op->op) { case FILTER_OP_LOAD_FIELD_REF: - return apply_field_reloc(event, runtime, runtime_len, + return apply_field_reloc(event_desc, runtime, runtime_len, reloc_offset, name, op->op); case FILTER_OP_GET_CONTEXT_REF: - return apply_context_reloc(event, runtime, runtime_len, + return apply_context_reloc(runtime, runtime_len, reloc_offset, name, op->op); case FILTER_OP_GET_SYMBOL: case FILTER_OP_GET_SYMBOL_FIELD: @@ -408,12 +405,11 @@ int apply_reloc(struct lttng_event *event, static int bytecode_is_linked(struct lttng_ust_filter_bytecode_node *filter_bytecode, - struct lttng_event *event) + struct cds_list_head *bytecode_runtime_head) { struct lttng_bytecode_runtime *bc_runtime; - cds_list_for_each_entry(bc_runtime, - &event->bytecode_runtime_head, node) { + cds_list_for_each_entry(bc_runtime, bytecode_runtime_head, node) { if (bc_runtime->bc == filter_bytecode) return 1; } @@ -425,7 +421,8 @@ int bytecode_is_linked(struct lttng_ust_filter_bytecode_node *filter_bytecode, * bytecode runtime. */ static -int _lttng_filter_event_link_bytecode(struct lttng_event *event, +int _lttng_filter_link_bytecode(const struct lttng_event_desc *event_desc, + struct lttng_ctx **ctx, struct lttng_ust_filter_bytecode_node *filter_bytecode, struct cds_list_head *insert_loc) { @@ -436,7 +433,7 @@ int _lttng_filter_event_link_bytecode(struct lttng_event *event, if (!filter_bytecode) return 0; /* Bytecode already linked */ - if (bytecode_is_linked(filter_bytecode, event)) + if (bytecode_is_linked(filter_bytecode, insert_loc)) return 0; dbg_printf("Linking...\n"); @@ -449,7 +446,7 @@ int _lttng_filter_event_link_bytecode(struct lttng_event *event, goto alloc_error; } runtime->p.bc = filter_bytecode; - runtime->p.pctx = &event->chan->session->ctx; + runtime->p.pctx = ctx; runtime->len = filter_bytecode->bc.reloc_offset; /* copy original bytecode */ memcpy(runtime->code, filter_bytecode->bc.data, runtime->len); @@ -465,7 +462,7 @@ int _lttng_filter_event_link_bytecode(struct lttng_event *event, const char *name = (const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)]; - ret = apply_reloc(event, runtime, runtime->len, reloc_offset, name); + ret = apply_reloc(event_desc, runtime, runtime->len, reloc_offset, name); if (ret) { goto link_error; } @@ -477,7 +474,7 @@ int _lttng_filter_event_link_bytecode(struct lttng_event *event, goto link_error; } /* Specialize bytecode */ - ret = lttng_filter_specialize_bytecode(event, runtime); + ret = lttng_filter_specialize_bytecode(event_desc, runtime); if (ret) { goto link_error; } @@ -507,25 +504,25 @@ void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime) } /* - * Link bytecode for all enablers referenced by an event. + * Link all bytecodes of the enabler referenced in the provided bytecode list. */ -void lttng_event_enabler_link_bytecode(struct lttng_event *event, - struct lttng_event_enabler *event_enabler) +void lttng_enabler_link_bytecode(const struct lttng_event_desc *event_desc, + struct lttng_ctx **ctx, + struct cds_list_head *bytecode_runtime_head, + struct lttng_enabler *enabler) { struct lttng_ust_filter_bytecode_node *bc; struct lttng_bytecode_runtime *runtime; - struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler(event_enabler); - /* Can only be called for events with desc attached */ - assert(event->desc); + assert(event_desc); /* Link each bytecode. */ - cds_list_for_each_entry(bc, &base_enabler->filter_bytecode_head, node) { + cds_list_for_each_entry(bc, &enabler->filter_bytecode_head, node) { int found = 0, ret; struct cds_list_head *insert_loc; cds_list_for_each_entry(runtime, - &event->bytecode_runtime_head, node) { + bytecode_runtime_head, node) { if (runtime->bc == bc) { found = 1; break; @@ -541,19 +538,20 @@ void lttng_event_enabler_link_bytecode(struct lttng_event *event, * insert the new bytecode right after it. */ cds_list_for_each_entry_reverse(runtime, - &event->bytecode_runtime_head, node) { + bytecode_runtime_head, node) { if (runtime->bc->bc.seqnum <= bc->bc.seqnum) { /* insert here */ insert_loc = &runtime->node; goto add_within; } } + /* Add to head to list */ - insert_loc = &event->bytecode_runtime_head; + insert_loc = bytecode_runtime_head; add_within: dbg_printf("linking bytecode\n"); - ret = _lttng_filter_event_link_bytecode(event, bc, - insert_loc); + ret = _lttng_filter_link_bytecode(event_desc, ctx, bc, + insert_loc); if (ret) { dbg_printf("[lttng filter] warning: cannot link event bytecode\n"); } diff --git a/liblttng-ust/lttng-filter.h b/liblttng-ust/lttng-filter.h index cc15c154..f8e11293 100644 --- a/liblttng-ust/lttng-filter.h +++ b/liblttng-ust/lttng-filter.h @@ -291,7 +291,7 @@ struct estack { const char *print_op(enum filter_op op); int lttng_filter_validate_bytecode(struct bytecode_runtime *bytecode); -int lttng_filter_specialize_bytecode(struct lttng_event *event, +int lttng_filter_specialize_bytecode(const struct lttng_event_desc *event_desc, struct bytecode_runtime *bytecode); uint64_t lttng_filter_false(void *filter_data, diff --git a/liblttng-ust/ust-events-internal.h b/liblttng-ust/ust-events-internal.h index dbd998e8..649fd211 100644 --- a/liblttng-ust/ust-events-internal.h +++ b/liblttng-ust/ust-events-internal.h @@ -136,7 +136,9 @@ int lttng_event_enabler_attach_exclusion(struct lttng_event_enabler *enabler, * each is linked to the provided event. */ LTTNG_HIDDEN -void lttng_event_enabler_link_bytecode(struct lttng_event *event, - struct lttng_event_enabler *enabler); +void lttng_enabler_link_bytecode(const struct lttng_event_desc *event_desc, + struct lttng_ctx **ctx, + struct cds_list_head *bytecode_runtime_head, + struct lttng_enabler *enabler); #endif /* _LTTNG_UST_EVENTS_INTERNAL_H */ -- 2.34.1