perf bpf filter: Give terms their own enum

Give the term types their own enum so that additional terms can be
added that don't correspond to a PERF_SAMPLE_xx flag. The term values
are numerically ascending rather than bit field positions, this means
they need translating to a PERF_SAMPLE_xx bit field in certain places
using a shift.

Signed-off-by: Ian Rogers <[e-mail]>
Acked-by: Namhyung Kim <[e-mail]>
Cc: John Fastabend <[e-mail]>
Cc: Changbin Du <[e-mail]>
Cc: Yang Jihong <[e-mail]>
Cc: Andrii Nakryiko <[e-mail]>
Cc: [e-mail]
Signed-off-by: Namhyung Kim <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

tools/perf/util/bpf-filter.c

···
 
 #define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
 
-#define __PERF_SAMPLE_TYPE(st, opt)	{ st, #st, opt }
-#define PERF_SAMPLE_TYPE(_st, opt)	__PERF_SAMPLE_TYPE(PERF_SAMPLE_##_st, opt)
+#define __PERF_SAMPLE_TYPE(tt, st, opt)	{ tt, #st, opt }
+#define PERF_SAMPLE_TYPE(_st, opt)	__PERF_SAMPLE_TYPE(PBF_TERM_##_st, PERF_SAMPLE_##_st, opt)
 
 static const struct perf_sample_info {
-	u64 type;
+	enum perf_bpf_filter_term type;
 	const char *name;
 	const char *option;
 } sample_table[] = {
···
 	PERF_SAMPLE_TYPE(DATA_PAGE_SIZE, "--data-page-size"),
 };
 
-static const struct perf_sample_info *get_sample_info(u64 flags)
+static const struct perf_sample_info *get_sample_info(enum perf_bpf_filter_term type)
 {
 	size_t i;
 
 	for (i = 0; i < ARRAY_SIZE(sample_table); i++) {
-		if (sample_table[i].type == flags)
+		if (sample_table[i].type == type)
 			return &sample_table[i];
 	}
 	return NULL;
···
 {
 	const struct perf_sample_info *info;
 
-	if (evsel->core.attr.sample_type & expr->sample_flags)
+	if (expr->term >= PBF_TERM_SAMPLE_START && expr->term <= PBF_TERM_SAMPLE_END &&
+	    (evsel->core.attr.sample_type & (1 << (expr->term - PBF_TERM_SAMPLE_START))))
 		return 0;
 
 	if (expr->op == PBF_OP_GROUP_BEGIN) {
···
 		return 0;
 	}
 
-	info = get_sample_info(expr->sample_flags);
+	info = get_sample_info(expr->term);
 	if (info == NULL) {
-		pr_err("Error: %s event does not have sample flags %lx\n",
-		       evsel__name(evsel), expr->sample_flags);
+		pr_err("Error: %s event does not have sample flags %d\n",
+		       evsel__name(evsel), expr->term);
 		return -1;
 	}
 
···
 		struct perf_bpf_filter_entry entry = {
 			.op = expr->op,
 			.part = expr->part,
-			.flags = expr->sample_flags,
+			.term = expr->term,
 			.value = expr->val,
 		};
 
···
 				struct perf_bpf_filter_entry group_entry = {
 					.op = group->op,
 					.part = group->part,
-					.flags = group->sample_flags,
+					.term = group->term,
 					.value = group->val,
 				};
 				bpf_map_update_elem(fd, &i, &group_entry, BPF_ANY);
···
 	return skel ? skel->bss->dropped : 0;
 }
 
-struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flags, int part,
+struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(enum perf_bpf_filter_term term,
+						       int part,
 						       enum perf_bpf_filter_op op,
 						       unsigned long val)
 {
···
 
 	expr = malloc(sizeof(*expr));
 	if (expr != NULL) {
-		expr->sample_flags = sample_flags;
+		expr->term = term;
 		expr->part = part;
 		expr->op = op;
 		expr->val = val;

tools/perf/util/bpf-filter.h

···
 	struct list_head groups;
 	enum perf_bpf_filter_op op;
 	int part;
-	unsigned long sample_flags;
+	enum perf_bpf_filter_term term;
 	unsigned long val;
 };
 
 struct evsel;
 
 #ifdef HAVE_BPF_SKEL
-struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flags, int part,
+struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(enum perf_bpf_filter_term term,
+						       int part,
 						       enum perf_bpf_filter_op op,
 						       unsigned long val);
 int perf_bpf_filter__parse(struct list_head *expr_head, const char *str);

tools/perf/util/bpf-filter.l

···
 #include "bpf-filter.h"
 #include "bpf-filter-bison.h"
 
-static int sample(unsigned long sample_flag)
+static int sample(enum perf_bpf_filter_term term)
 {
-	perf_bpf_filter_lval.sample.type = sample_flag;
+	perf_bpf_filter_lval.sample.term = term;
 	perf_bpf_filter_lval.sample.part = 0;
 	return BFT_SAMPLE;
 }
 
-static int sample_part(unsigned long sample_flag, int part)
+static int sample_part(enum perf_bpf_filter_term term, int part)
 {
-	perf_bpf_filter_lval.sample.type = sample_flag;
+	perf_bpf_filter_lval.sample.term = term;
 	perf_bpf_filter_lval.sample.part = part;
 	return BFT_SAMPLE;
 }
···
 {num_hex}	{ return value(16); }
 {space}		{ }
 
-ip		{ return sample(PERF_SAMPLE_IP); }
-id		{ return sample(PERF_SAMPLE_ID); }
-tid		{ return sample(PERF_SAMPLE_TID); }
-pid		{ return sample_part(PERF_SAMPLE_TID, 1); }
-cpu		{ return sample(PERF_SAMPLE_CPU); }
-time		{ return sample(PERF_SAMPLE_TIME); }
-addr		{ return sample(PERF_SAMPLE_ADDR); }
-period		{ return sample(PERF_SAMPLE_PERIOD); }
-txn		{ return sample(PERF_SAMPLE_TRANSACTION); }
-weight		{ return sample(PERF_SAMPLE_WEIGHT); }
-weight1		{ return sample_part(PERF_SAMPLE_WEIGHT_STRUCT, 1); }
-weight2		{ return sample_part(PERF_SAMPLE_WEIGHT_STRUCT, 2); }
-weight3		{ return sample_part(PERF_SAMPLE_WEIGHT_STRUCT, 3); }
-ins_lat		{ return sample_part(PERF_SAMPLE_WEIGHT_STRUCT, 2); } /* alias for weight2 */
-p_stage_cyc	{ return sample_part(PERF_SAMPLE_WEIGHT_STRUCT, 3); } /* alias for weight3 */
-retire_lat	{ return sample_part(PERF_SAMPLE_WEIGHT_STRUCT, 3); } /* alias for weight3 */
-phys_addr	{ return sample(PERF_SAMPLE_PHYS_ADDR); }
-code_pgsz	{ return sample(PERF_SAMPLE_CODE_PAGE_SIZE); }
-data_pgsz	{ return sample(PERF_SAMPLE_DATA_PAGE_SIZE); }
-mem_op		{ return sample_part(PERF_SAMPLE_DATA_SRC, 1); }
-mem_lvlnum	{ return sample_part(PERF_SAMPLE_DATA_SRC, 2); }
-mem_lvl		{ return sample_part(PERF_SAMPLE_DATA_SRC, 2); } /* alias for mem_lvlnum */
-mem_snoop	{ return sample_part(PERF_SAMPLE_DATA_SRC, 3); } /* include snoopx */
-mem_remote	{ return sample_part(PERF_SAMPLE_DATA_SRC, 4); }
-mem_lock	{ return sample_part(PERF_SAMPLE_DATA_SRC, 5); }
-mem_dtlb	{ return sample_part(PERF_SAMPLE_DATA_SRC, 6); }
-mem_blk		{ return sample_part(PERF_SAMPLE_DATA_SRC, 7); }
-mem_hops	{ return sample_part(PERF_SAMPLE_DATA_SRC, 8); }
+ip		{ return sample(PBF_TERM_IP); }
+id		{ return sample(PBF_TERM_ID); }
+tid		{ return sample(PBF_TERM_TID); }
+pid		{ return sample_part(PBF_TERM_TID, 1); }
+cpu		{ return sample(PBF_TERM_CPU); }
+time		{ return sample(PBF_TERM_TIME); }
+addr		{ return sample(PBF_TERM_ADDR); }
+period		{ return sample(PBF_TERM_PERIOD); }
+txn		{ return sample(PBF_TERM_TRANSACTION); }
+weight		{ return sample(PBF_TERM_WEIGHT); }
+weight1		{ return sample_part(PBF_TERM_WEIGHT_STRUCT, 1); }
+weight2		{ return sample_part(PBF_TERM_WEIGHT_STRUCT, 2); }
+weight3		{ return sample_part(PBF_TERM_WEIGHT_STRUCT, 3); }
+ins_lat		{ return sample_part(PBF_TERM_WEIGHT_STRUCT, 2); } /* alias for weight2 */
+p_stage_cyc	{ return sample_part(PBF_TERM_WEIGHT_STRUCT, 3); } /* alias for weight3 */
+retire_lat	{ return sample_part(PBF_TERM_WEIGHT_STRUCT, 3); } /* alias for weight3 */
+phys_addr	{ return sample(PBF_TERM_PHYS_ADDR); }
+code_pgsz	{ return sample(PBF_TERM_CODE_PAGE_SIZE); }
+data_pgsz	{ return sample(PBF_TERM_DATA_PAGE_SIZE); }
+mem_op		{ return sample_part(PBF_TERM_DATA_SRC, 1); }
+mem_lvlnum	{ return sample_part(PBF_TERM_DATA_SRC, 2); }
+mem_lvl		{ return sample_part(PBF_TERM_DATA_SRC, 2); } /* alias for mem_lvlnum */
+mem_snoop	{ return sample_part(PBF_TERM_DATA_SRC, 3); } /* include snoopx */
+mem_remote	{ return sample_part(PBF_TERM_DATA_SRC, 4); }
+mem_lock	{ return sample_part(PBF_TERM_DATA_SRC, 5); }
+mem_dtlb	{ return sample_part(PBF_TERM_DATA_SRC, 6); }
+mem_blk		{ return sample_part(PBF_TERM_DATA_SRC, 7); }
+mem_hops	{ return sample_part(PBF_TERM_DATA_SRC, 8); }
 
 "=="		{ return operator(PBF_OP_EQ); }
 "!="		{ return operator(PBF_OP_NEQ); }

tools/perf/util/bpf-filter.y

···
 {
 	unsigned long num;
 	struct {
-		unsigned long type;
+		enum perf_bpf_filter_term term;
 		int part;
 	} sample;
 	enum perf_bpf_filter_op op;
···
 	if ($1->op == PBF_OP_GROUP_BEGIN) {
 		expr = $1;
 	} else {
-		expr = perf_bpf_filter_expr__new(0, 0, PBF_OP_GROUP_BEGIN, 1);
+		expr = perf_bpf_filter_expr__new(PBF_TERM_NONE, /*part=*/0,
+						 PBF_OP_GROUP_BEGIN, /*val=*/1);
 		list_add_tail(&$1->list, &expr->groups);
 	}
 	expr->val++;
···
 filter_expr:
 BFT_SAMPLE BFT_OP BFT_NUM
 {
-	$$ = perf_bpf_filter_expr__new($1.type, $1.part, $2, $3);
+	$$ = perf_bpf_filter_expr__new($1.term, $1.part, $2, $3);
 }
 
 %%

tools/perf/util/bpf_skel/sample-filter.h

···
 	PBF_OP_GROUP_END,
 };
 
+enum perf_bpf_filter_term {
+	/* No term is in use. */
+	PBF_TERM_NONE = 0,
+	/* Terms that correspond to PERF_SAMPLE_xx values. */
+	PBF_TERM_SAMPLE_START	= PBF_TERM_NONE + 1,
+	PBF_TERM_IP		= PBF_TERM_SAMPLE_START + 0, /* SAMPLE_IP = 1U << 0 */
+	PBF_TERM_TID		= PBF_TERM_SAMPLE_START + 1, /* SAMPLE_TID = 1U << 1 */
+	PBF_TERM_TIME		= PBF_TERM_SAMPLE_START + 2, /* SAMPLE_TIME = 1U << 2 */
+	PBF_TERM_ADDR		= PBF_TERM_SAMPLE_START + 3, /* SAMPLE_ADDR = 1U << 3 */
+	__PBF_UNUSED_TERM4	= PBF_TERM_SAMPLE_START + 4, /* SAMPLE_READ = 1U << 4 */
+	__PBF_UNUSED_TERM5	= PBF_TERM_SAMPLE_START + 5, /* SAMPLE_CALLCHAIN = 1U << 5 */
+	PBF_TERM_ID		= PBF_TERM_SAMPLE_START + 6, /* SAMPLE_ID = 1U << 6 */
+	PBF_TERM_CPU		= PBF_TERM_SAMPLE_START + 7, /* SAMPLE_CPU = 1U << 7 */
+	PBF_TERM_PERIOD		= PBF_TERM_SAMPLE_START + 8, /* SAMPLE_PERIOD = 1U << 8 */
+	__PBF_UNUSED_TERM9	= PBF_TERM_SAMPLE_START + 9, /* SAMPLE_STREAM_ID = 1U << 9 */
+	__PBF_UNUSED_TERM10	= PBF_TERM_SAMPLE_START + 10, /* SAMPLE_RAW = 1U << 10 */
+	__PBF_UNUSED_TERM11	= PBF_TERM_SAMPLE_START + 11, /* SAMPLE_BRANCH_STACK = 1U << 11 */
+	__PBF_UNUSED_TERM12	= PBF_TERM_SAMPLE_START + 12, /* SAMPLE_REGS_USER = 1U << 12 */
+	__PBF_UNUSED_TERM13	= PBF_TERM_SAMPLE_START + 13, /* SAMPLE_STACK_USER = 1U << 13 */
+	PBF_TERM_WEIGHT		= PBF_TERM_SAMPLE_START + 14, /* SAMPLE_WEIGHT = 1U << 14 */
+	PBF_TERM_DATA_SRC	= PBF_TERM_SAMPLE_START + 15, /* SAMPLE_DATA_SRC = 1U << 15 */
+	__PBF_UNUSED_TERM16	= PBF_TERM_SAMPLE_START + 16, /* SAMPLE_IDENTIFIER = 1U << 16 */
+	PBF_TERM_TRANSACTION	= PBF_TERM_SAMPLE_START + 17, /* SAMPLE_TRANSACTION = 1U << 17 */
+	__PBF_UNUSED_TERM18	= PBF_TERM_SAMPLE_START + 18, /* SAMPLE_REGS_INTR = 1U << 18 */
+	PBF_TERM_PHYS_ADDR	= PBF_TERM_SAMPLE_START + 19, /* SAMPLE_PHYS_ADDR = 1U << 19 */
+	__PBF_UNUSED_TERM20	= PBF_TERM_SAMPLE_START + 20, /* SAMPLE_AUX = 1U << 20 */
+	__PBF_UNUSED_TERM21	= PBF_TERM_SAMPLE_START + 21, /* SAMPLE_CGROUP = 1U << 21 */
+	PBF_TERM_DATA_PAGE_SIZE	= PBF_TERM_SAMPLE_START + 22, /* SAMPLE_DATA_PAGE_SIZE = 1U << 22 */
+	PBF_TERM_CODE_PAGE_SIZE	= PBF_TERM_SAMPLE_START + 23, /* SAMPLE_CODE_PAGE_SIZE = 1U << 23 */
+	PBF_TERM_WEIGHT_STRUCT	= PBF_TERM_SAMPLE_START + 24, /* SAMPLE_WEIGHT_STRUCT = 1U << 24 */
+	PBF_TERM_SAMPLE_END	= PBF_TERM_WEIGHT_STRUCT,
+};
+
 /* BPF map entry for filtering */
 struct perf_bpf_filter_entry {
 	enum perf_bpf_filter_op op;
 	__u32 part; /* sub-sample type info when it has multiple values */
-	__u64 flags; /* perf sample type flags */
+	enum perf_bpf_filter_term term;
 	__u64 value;
 };
 

tools/perf/util/bpf_skel/sample_filter.bpf.c

···
 {
 	struct perf_sample_data___new *data = (void *)kctx->data;
 
-	if (!bpf_core_field_exists(data->sample_flags) ||
-	    (data->sample_flags & entry->flags) == 0)
+	if (!bpf_core_field_exists(data->sample_flags))
 		return 0;
 
-	switch (entry->flags) {
-	case PERF_SAMPLE_IP:
+#define BUILD_CHECK_SAMPLE(x)					\
+	_Static_assert((1 << (PBF_TERM_##x - PBF_TERM_SAMPLE_START)) == PERF_SAMPLE_##x, \
+		"Mismatched PBF term to sample bit " #x)
+	BUILD_CHECK_SAMPLE(IP);
+	BUILD_CHECK_SAMPLE(TID);
+	BUILD_CHECK_SAMPLE(TIME);
+	BUILD_CHECK_SAMPLE(ADDR);
+	BUILD_CHECK_SAMPLE(ID);
+	BUILD_CHECK_SAMPLE(CPU);
+	BUILD_CHECK_SAMPLE(PERIOD);
+	BUILD_CHECK_SAMPLE(WEIGHT);
+	BUILD_CHECK_SAMPLE(DATA_SRC);
+	BUILD_CHECK_SAMPLE(TRANSACTION);
+	BUILD_CHECK_SAMPLE(PHYS_ADDR);
+	BUILD_CHECK_SAMPLE(DATA_PAGE_SIZE);
+	BUILD_CHECK_SAMPLE(CODE_PAGE_SIZE);
+	BUILD_CHECK_SAMPLE(WEIGHT_STRUCT);
+#undef BUILD_CHECK_SAMPLE
+
+	/* For sample terms check the sample bit is set. */
+	if (entry->term >= PBF_TERM_SAMPLE_START && entry->term <= PBF_TERM_SAMPLE_END &&
+	    (data->sample_flags & (1 << (entry->term - PBF_TERM_SAMPLE_START))) == 0)
+		return 0;
+
+	switch (entry->term) {
+	case PBF_TERM_IP:
 		return kctx->data->ip;
-	case PERF_SAMPLE_ID:
+	case PBF_TERM_ID:
 		return kctx->data->id;
-	case PERF_SAMPLE_TID:
+	case PBF_TERM_TID:
 		if (entry->part)
 			return kctx->data->tid_entry.pid;
 		else
 			return kctx->data->tid_entry.tid;
-	case PERF_SAMPLE_CPU:
+	case PBF_TERM_CPU:
 		return kctx->data->cpu_entry.cpu;
-	case PERF_SAMPLE_TIME:
+	case PBF_TERM_TIME:
 		return kctx->data->time;
-	case PERF_SAMPLE_ADDR:
+	case PBF_TERM_ADDR:
 		return kctx->data->addr;
-	case PERF_SAMPLE_PERIOD:
+	case PBF_TERM_PERIOD:
 		return kctx->data->period;
-	case PERF_SAMPLE_TRANSACTION:
+	case PBF_TERM_TRANSACTION:
 		return kctx->data->txn;
-	case PERF_SAMPLE_WEIGHT_STRUCT:
+	case PBF_TERM_WEIGHT_STRUCT:
 		if (entry->part == 1)
 			return kctx->data->weight.var1_dw;
 		if (entry->part == 2)
···
 		if (entry->part == 3)
 			return kctx->data->weight.var3_w;
 		/* fall through */
-	case PERF_SAMPLE_WEIGHT:
+	case PBF_TERM_WEIGHT:
 		return kctx->data->weight.full;
-	case PERF_SAMPLE_PHYS_ADDR:
+	case PBF_TERM_PHYS_ADDR:
 		return kctx->data->phys_addr;
-	case PERF_SAMPLE_CODE_PAGE_SIZE:
+	case PBF_TERM_CODE_PAGE_SIZE:
 		return kctx->data->code_page_size;
-	case PERF_SAMPLE_DATA_PAGE_SIZE:
+	case PBF_TERM_DATA_PAGE_SIZE:
 		return kctx->data->data_page_size;
-	case PERF_SAMPLE_DATA_SRC:
+	case PBF_TERM_DATA_SRC:
 		if (entry->part == 1)
 			return kctx->data->data_src.mem_op;
 		if (entry->part == 2)
···
 		}
 		/* return the whole word */
 		return kctx->data->data_src.val;
+	case PBF_TERM_NONE:
+	case __PBF_UNUSED_TERM4:
+	case __PBF_UNUSED_TERM5:
+	case __PBF_UNUSED_TERM9:
+	case __PBF_UNUSED_TERM10:
+	case __PBF_UNUSED_TERM11:
+	case __PBF_UNUSED_TERM12:
+	case __PBF_UNUSED_TERM13:
+	case __PBF_UNUSED_TERM16:
+	case __PBF_UNUSED_TERM18:
+	case __PBF_UNUSED_TERM20:
+	case __PBF_UNUSED_TERM21:
 	default:
 		break;
 	}