mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-27 04:47:05 +00:00
8999971292
commitdc432c3d7f
upstream. The regex match function regex_match_front() in the tracing filter logic, was fixed to test just the pattern length from testing the entire test string. That is, it went from strncmp(str, r->pattern, len) to strcmp(str, r->pattern, r->len). The issue is that str is not guaranteed to be nul terminated, and if r->len is greater than the length of str, it can access more memory than is allocated. The solution is to add a simple test if (len < r->len) return 0. Cc: stable@vger.kernel.org Fixes:285caad415
("tracing/filters: Fix MATCH_FRONT_ONLY filter matching") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2476 lines
55 KiB
C
2476 lines
55 KiB
C
/*
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* trace_events_filter - generic event filtering
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*
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* Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com>
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*/
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#include <linux/module.h>
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#include <linux/ctype.h>
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#include <linux/mutex.h>
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#include <linux/perf_event.h>
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#include <linux/slab.h>
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#include "trace.h"
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#include "trace_output.h"
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#define DEFAULT_SYS_FILTER_MESSAGE \
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"### global filter ###\n" \
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"# Use this to set filters for multiple events.\n" \
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"# Only events with the given fields will be affected.\n" \
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"# If no events are modified, an error message will be displayed here"
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enum filter_op_ids
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{
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OP_OR,
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OP_AND,
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OP_GLOB,
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OP_NE,
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OP_EQ,
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OP_LT,
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OP_LE,
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OP_GT,
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OP_GE,
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OP_BAND,
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OP_NOT,
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OP_NONE,
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OP_OPEN_PAREN,
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};
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struct filter_op {
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int id;
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char *string;
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int precedence;
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};
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/* Order must be the same as enum filter_op_ids above */
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static struct filter_op filter_ops[] = {
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{ OP_OR, "||", 1 },
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{ OP_AND, "&&", 2 },
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{ OP_GLOB, "~", 4 },
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{ OP_NE, "!=", 4 },
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{ OP_EQ, "==", 4 },
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{ OP_LT, "<", 5 },
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{ OP_LE, "<=", 5 },
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{ OP_GT, ">", 5 },
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{ OP_GE, ">=", 5 },
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{ OP_BAND, "&", 6 },
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{ OP_NOT, "!", 6 },
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{ OP_NONE, "OP_NONE", 0 },
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{ OP_OPEN_PAREN, "(", 0 },
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};
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enum {
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FILT_ERR_NONE,
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FILT_ERR_INVALID_OP,
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FILT_ERR_UNBALANCED_PAREN,
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FILT_ERR_TOO_MANY_OPERANDS,
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FILT_ERR_OPERAND_TOO_LONG,
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FILT_ERR_FIELD_NOT_FOUND,
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FILT_ERR_ILLEGAL_FIELD_OP,
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FILT_ERR_ILLEGAL_INTVAL,
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FILT_ERR_BAD_SUBSYS_FILTER,
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FILT_ERR_TOO_MANY_PREDS,
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FILT_ERR_MISSING_FIELD,
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FILT_ERR_INVALID_FILTER,
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FILT_ERR_IP_FIELD_ONLY,
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FILT_ERR_ILLEGAL_NOT_OP,
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};
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static char *err_text[] = {
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"No error",
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"Invalid operator",
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"Unbalanced parens",
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"Too many operands",
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"Operand too long",
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"Field not found",
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"Illegal operation for field type",
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"Illegal integer value",
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"Couldn't find or set field in one of a subsystem's events",
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"Too many terms in predicate expression",
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"Missing field name and/or value",
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"Meaningless filter expression",
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"Only 'ip' field is supported for function trace",
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"Illegal use of '!'",
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};
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struct opstack_op {
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enum filter_op_ids op;
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struct list_head list;
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};
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struct postfix_elt {
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enum filter_op_ids op;
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char *operand;
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struct list_head list;
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};
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struct filter_parse_state {
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struct filter_op *ops;
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struct list_head opstack;
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struct list_head postfix;
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int lasterr;
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int lasterr_pos;
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struct {
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char *string;
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unsigned int cnt;
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unsigned int tail;
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} infix;
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struct {
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char string[MAX_FILTER_STR_VAL];
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int pos;
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unsigned int tail;
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} operand;
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};
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struct pred_stack {
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struct filter_pred **preds;
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int index;
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};
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/* If not of not match is equal to not of not, then it is a match */
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#define DEFINE_COMPARISON_PRED(type) \
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static int filter_pred_LT_##type(struct filter_pred *pred, void *event) \
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{ \
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type *addr = (type *)(event + pred->offset); \
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type val = (type)pred->val; \
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int match = (*addr < val); \
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return !!match == !pred->not; \
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} \
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static int filter_pred_LE_##type(struct filter_pred *pred, void *event) \
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{ \
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type *addr = (type *)(event + pred->offset); \
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type val = (type)pred->val; \
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int match = (*addr <= val); \
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return !!match == !pred->not; \
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} \
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static int filter_pred_GT_##type(struct filter_pred *pred, void *event) \
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{ \
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type *addr = (type *)(event + pred->offset); \
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type val = (type)pred->val; \
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int match = (*addr > val); \
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return !!match == !pred->not; \
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} \
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static int filter_pred_GE_##type(struct filter_pred *pred, void *event) \
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{ \
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type *addr = (type *)(event + pred->offset); \
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type val = (type)pred->val; \
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int match = (*addr >= val); \
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return !!match == !pred->not; \
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} \
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static int filter_pred_BAND_##type(struct filter_pred *pred, void *event) \
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{ \
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type *addr = (type *)(event + pred->offset); \
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type val = (type)pred->val; \
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int match = !!(*addr & val); \
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return match == !pred->not; \
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} \
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static const filter_pred_fn_t pred_funcs_##type[] = { \
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filter_pred_LT_##type, \
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filter_pred_LE_##type, \
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filter_pred_GT_##type, \
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filter_pred_GE_##type, \
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filter_pred_BAND_##type, \
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};
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#define PRED_FUNC_START OP_LT
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#define DEFINE_EQUALITY_PRED(size) \
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static int filter_pred_##size(struct filter_pred *pred, void *event) \
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{ \
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u##size *addr = (u##size *)(event + pred->offset); \
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u##size val = (u##size)pred->val; \
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int match; \
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\
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match = (val == *addr) ^ pred->not; \
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\
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return match; \
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}
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DEFINE_COMPARISON_PRED(s64);
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DEFINE_COMPARISON_PRED(u64);
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DEFINE_COMPARISON_PRED(s32);
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DEFINE_COMPARISON_PRED(u32);
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DEFINE_COMPARISON_PRED(s16);
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DEFINE_COMPARISON_PRED(u16);
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DEFINE_COMPARISON_PRED(s8);
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DEFINE_COMPARISON_PRED(u8);
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DEFINE_EQUALITY_PRED(64);
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DEFINE_EQUALITY_PRED(32);
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DEFINE_EQUALITY_PRED(16);
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DEFINE_EQUALITY_PRED(8);
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/* Filter predicate for fixed sized arrays of characters */
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static int filter_pred_string(struct filter_pred *pred, void *event)
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{
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char *addr = (char *)(event + pred->offset);
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int cmp, match;
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cmp = pred->regex.match(addr, &pred->regex, pred->regex.field_len);
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match = cmp ^ pred->not;
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return match;
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}
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/* Filter predicate for char * pointers */
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static int filter_pred_pchar(struct filter_pred *pred, void *event)
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{
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char **addr = (char **)(event + pred->offset);
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int cmp, match;
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int len = strlen(*addr) + 1; /* including tailing '\0' */
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cmp = pred->regex.match(*addr, &pred->regex, len);
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match = cmp ^ pred->not;
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return match;
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}
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/*
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* Filter predicate for dynamic sized arrays of characters.
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* These are implemented through a list of strings at the end
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* of the entry.
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* Also each of these strings have a field in the entry which
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* contains its offset from the beginning of the entry.
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* We have then first to get this field, dereference it
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* and add it to the address of the entry, and at last we have
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* the address of the string.
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*/
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static int filter_pred_strloc(struct filter_pred *pred, void *event)
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{
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u32 str_item = *(u32 *)(event + pred->offset);
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int str_loc = str_item & 0xffff;
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int str_len = str_item >> 16;
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char *addr = (char *)(event + str_loc);
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int cmp, match;
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cmp = pred->regex.match(addr, &pred->regex, str_len);
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match = cmp ^ pred->not;
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return match;
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}
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/* Filter predicate for CPUs. */
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static int filter_pred_cpu(struct filter_pred *pred, void *event)
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{
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int cpu, cmp;
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int match = 0;
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cpu = raw_smp_processor_id();
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cmp = pred->val;
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switch (pred->op) {
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case OP_EQ:
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match = cpu == cmp;
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break;
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case OP_LT:
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match = cpu < cmp;
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break;
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case OP_LE:
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match = cpu <= cmp;
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break;
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case OP_GT:
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match = cpu > cmp;
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break;
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case OP_GE:
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match = cpu >= cmp;
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break;
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default:
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break;
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}
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return !!match == !pred->not;
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}
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/* Filter predicate for COMM. */
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static int filter_pred_comm(struct filter_pred *pred, void *event)
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{
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int cmp, match;
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cmp = pred->regex.match(current->comm, &pred->regex,
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pred->regex.field_len);
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match = cmp ^ pred->not;
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return match;
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}
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static int filter_pred_none(struct filter_pred *pred, void *event)
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{
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return 0;
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}
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/*
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* regex_match_foo - Basic regex callbacks
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*
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* @str: the string to be searched
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* @r: the regex structure containing the pattern string
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* @len: the length of the string to be searched (including '\0')
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*
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* Note:
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* - @str might not be NULL-terminated if it's of type DYN_STRING
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* or STATIC_STRING
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*/
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static int regex_match_full(char *str, struct regex *r, int len)
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{
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if (strncmp(str, r->pattern, len) == 0)
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return 1;
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return 0;
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}
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static int regex_match_front(char *str, struct regex *r, int len)
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{
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if (len < r->len)
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return 0;
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if (strncmp(str, r->pattern, r->len) == 0)
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return 1;
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return 0;
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}
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static int regex_match_middle(char *str, struct regex *r, int len)
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{
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if (strnstr(str, r->pattern, len))
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return 1;
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return 0;
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}
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static int regex_match_end(char *str, struct regex *r, int len)
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{
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int strlen = len - 1;
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if (strlen >= r->len &&
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memcmp(str + strlen - r->len, r->pattern, r->len) == 0)
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return 1;
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return 0;
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}
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static int regex_match_glob(char *str, struct regex *r, int len __maybe_unused)
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{
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if (glob_match(r->pattern, str))
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return 1;
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return 0;
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}
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/**
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* filter_parse_regex - parse a basic regex
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* @buff: the raw regex
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* @len: length of the regex
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* @search: will point to the beginning of the string to compare
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* @not: tell whether the match will have to be inverted
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*
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* This passes in a buffer containing a regex and this function will
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* set search to point to the search part of the buffer and
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* return the type of search it is (see enum above).
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* This does modify buff.
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*
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* Returns enum type.
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* search returns the pointer to use for comparison.
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* not returns 1 if buff started with a '!'
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* 0 otherwise.
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*/
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enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not)
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{
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int type = MATCH_FULL;
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int i;
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if (buff[0] == '!') {
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*not = 1;
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buff++;
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len--;
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} else
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*not = 0;
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*search = buff;
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for (i = 0; i < len; i++) {
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if (buff[i] == '*') {
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if (!i) {
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type = MATCH_END_ONLY;
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} else if (i == len - 1) {
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if (type == MATCH_END_ONLY)
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type = MATCH_MIDDLE_ONLY;
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else
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type = MATCH_FRONT_ONLY;
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buff[i] = 0;
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break;
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} else { /* pattern continues, use full glob */
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return MATCH_GLOB;
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}
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} else if (strchr("[?\\", buff[i])) {
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return MATCH_GLOB;
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}
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}
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if (buff[0] == '*')
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*search = buff + 1;
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return type;
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}
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static void filter_build_regex(struct filter_pred *pred)
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{
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struct regex *r = &pred->regex;
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char *search;
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enum regex_type type = MATCH_FULL;
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int not = 0;
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if (pred->op == OP_GLOB) {
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type = filter_parse_regex(r->pattern, r->len, &search, ¬);
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r->len = strlen(search);
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memmove(r->pattern, search, r->len+1);
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}
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switch (type) {
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case MATCH_FULL:
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r->match = regex_match_full;
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break;
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case MATCH_FRONT_ONLY:
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r->match = regex_match_front;
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break;
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case MATCH_MIDDLE_ONLY:
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r->match = regex_match_middle;
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break;
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case MATCH_END_ONLY:
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r->match = regex_match_end;
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break;
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case MATCH_GLOB:
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r->match = regex_match_glob;
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break;
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}
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pred->not ^= not;
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}
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enum move_type {
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MOVE_DOWN,
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MOVE_UP_FROM_LEFT,
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MOVE_UP_FROM_RIGHT
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};
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static struct filter_pred *
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get_pred_parent(struct filter_pred *pred, struct filter_pred *preds,
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int index, enum move_type *move)
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{
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if (pred->parent & FILTER_PRED_IS_RIGHT)
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*move = MOVE_UP_FROM_RIGHT;
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else
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*move = MOVE_UP_FROM_LEFT;
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pred = &preds[pred->parent & ~FILTER_PRED_IS_RIGHT];
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return pred;
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}
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enum walk_return {
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WALK_PRED_ABORT,
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WALK_PRED_PARENT,
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WALK_PRED_DEFAULT,
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};
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|
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typedef int (*filter_pred_walkcb_t) (enum move_type move,
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struct filter_pred *pred,
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int *err, void *data);
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|
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static int walk_pred_tree(struct filter_pred *preds,
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struct filter_pred *root,
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filter_pred_walkcb_t cb, void *data)
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{
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struct filter_pred *pred = root;
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enum move_type move = MOVE_DOWN;
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int done = 0;
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|
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if (!preds)
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return -EINVAL;
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|
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do {
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int err = 0, ret;
|
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ret = cb(move, pred, &err, data);
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if (ret == WALK_PRED_ABORT)
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return err;
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if (ret == WALK_PRED_PARENT)
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goto get_parent;
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|
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switch (move) {
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case MOVE_DOWN:
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if (pred->left != FILTER_PRED_INVALID) {
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pred = &preds[pred->left];
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continue;
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}
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goto get_parent;
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case MOVE_UP_FROM_LEFT:
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pred = &preds[pred->right];
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move = MOVE_DOWN;
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continue;
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case MOVE_UP_FROM_RIGHT:
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get_parent:
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if (pred == root)
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break;
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pred = get_pred_parent(pred, preds,
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pred->parent,
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&move);
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continue;
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}
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done = 1;
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} while (!done);
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|
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/* We are fine. */
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return 0;
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}
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|
|
/*
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|
* A series of AND or ORs where found together. Instead of
|
|
* climbing up and down the tree branches, an array of the
|
|
* ops were made in order of checks. We can just move across
|
|
* the array and short circuit if needed.
|
|
*/
|
|
static int process_ops(struct filter_pred *preds,
|
|
struct filter_pred *op, void *rec)
|
|
{
|
|
struct filter_pred *pred;
|
|
int match = 0;
|
|
int type;
|
|
int i;
|
|
|
|
/*
|
|
* Micro-optimization: We set type to true if op
|
|
* is an OR and false otherwise (AND). Then we
|
|
* just need to test if the match is equal to
|
|
* the type, and if it is, we can short circuit the
|
|
* rest of the checks:
|
|
*
|
|
* if ((match && op->op == OP_OR) ||
|
|
* (!match && op->op == OP_AND))
|
|
* return match;
|
|
*/
|
|
type = op->op == OP_OR;
|
|
|
|
for (i = 0; i < op->val; i++) {
|
|
pred = &preds[op->ops[i]];
|
|
if (!WARN_ON_ONCE(!pred->fn))
|
|
match = pred->fn(pred, rec);
|
|
if (!!match == type)
|
|
break;
|
|
}
|
|
/* If not of not match is equal to not of not, then it is a match */
|
|
return !!match == !op->not;
|
|
}
|
|
|
|
struct filter_match_preds_data {
|
|
struct filter_pred *preds;
|
|
int match;
|
|
void *rec;
|
|
};
|
|
|
|
static int filter_match_preds_cb(enum move_type move, struct filter_pred *pred,
|
|
int *err, void *data)
|
|
{
|
|
struct filter_match_preds_data *d = data;
|
|
|
|
*err = 0;
|
|
switch (move) {
|
|
case MOVE_DOWN:
|
|
/* only AND and OR have children */
|
|
if (pred->left != FILTER_PRED_INVALID) {
|
|
/* If ops is set, then it was folded. */
|
|
if (!pred->ops)
|
|
return WALK_PRED_DEFAULT;
|
|
/* We can treat folded ops as a leaf node */
|
|
d->match = process_ops(d->preds, pred, d->rec);
|
|
} else {
|
|
if (!WARN_ON_ONCE(!pred->fn))
|
|
d->match = pred->fn(pred, d->rec);
|
|
}
|
|
|
|
return WALK_PRED_PARENT;
|
|
case MOVE_UP_FROM_LEFT:
|
|
/*
|
|
* Check for short circuits.
|
|
*
|
|
* Optimization: !!match == (pred->op == OP_OR)
|
|
* is the same as:
|
|
* if ((match && pred->op == OP_OR) ||
|
|
* (!match && pred->op == OP_AND))
|
|
*/
|
|
if (!!d->match == (pred->op == OP_OR))
|
|
return WALK_PRED_PARENT;
|
|
break;
|
|
case MOVE_UP_FROM_RIGHT:
|
|
break;
|
|
}
|
|
|
|
return WALK_PRED_DEFAULT;
|
|
}
|
|
|
|
/* return 1 if event matches, 0 otherwise (discard) */
|
|
int filter_match_preds(struct event_filter *filter, void *rec)
|
|
{
|
|
struct filter_pred *preds;
|
|
struct filter_pred *root;
|
|
struct filter_match_preds_data data = {
|
|
/* match is currently meaningless */
|
|
.match = -1,
|
|
.rec = rec,
|
|
};
|
|
int n_preds, ret;
|
|
|
|
/* no filter is considered a match */
|
|
if (!filter)
|
|
return 1;
|
|
|
|
n_preds = filter->n_preds;
|
|
if (!n_preds)
|
|
return 1;
|
|
|
|
/*
|
|
* n_preds, root and filter->preds are protect with preemption disabled.
|
|
*/
|
|
root = rcu_dereference_sched(filter->root);
|
|
if (!root)
|
|
return 1;
|
|
|
|
data.preds = preds = rcu_dereference_sched(filter->preds);
|
|
ret = walk_pred_tree(preds, root, filter_match_preds_cb, &data);
|
|
WARN_ON(ret);
|
|
return data.match;
|
|
}
|
|
EXPORT_SYMBOL_GPL(filter_match_preds);
|
|
|
|
static void parse_error(struct filter_parse_state *ps, int err, int pos)
|
|
{
|
|
ps->lasterr = err;
|
|
ps->lasterr_pos = pos;
|
|
}
|
|
|
|
static void remove_filter_string(struct event_filter *filter)
|
|
{
|
|
if (!filter)
|
|
return;
|
|
|
|
kfree(filter->filter_string);
|
|
filter->filter_string = NULL;
|
|
}
|
|
|
|
static int replace_filter_string(struct event_filter *filter,
|
|
char *filter_string)
|
|
{
|
|
kfree(filter->filter_string);
|
|
filter->filter_string = kstrdup(filter_string, GFP_KERNEL);
|
|
if (!filter->filter_string)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int append_filter_string(struct event_filter *filter,
|
|
char *string)
|
|
{
|
|
int newlen;
|
|
char *new_filter_string;
|
|
|
|
BUG_ON(!filter->filter_string);
|
|
newlen = strlen(filter->filter_string) + strlen(string) + 1;
|
|
new_filter_string = kmalloc(newlen, GFP_KERNEL);
|
|
if (!new_filter_string)
|
|
return -ENOMEM;
|
|
|
|
strcpy(new_filter_string, filter->filter_string);
|
|
strcat(new_filter_string, string);
|
|
kfree(filter->filter_string);
|
|
filter->filter_string = new_filter_string;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void append_filter_err(struct filter_parse_state *ps,
|
|
struct event_filter *filter)
|
|
{
|
|
int pos = ps->lasterr_pos;
|
|
char *buf, *pbuf;
|
|
|
|
buf = (char *)__get_free_page(GFP_KERNEL);
|
|
if (!buf)
|
|
return;
|
|
|
|
append_filter_string(filter, "\n");
|
|
memset(buf, ' ', PAGE_SIZE);
|
|
if (pos > PAGE_SIZE - 128)
|
|
pos = 0;
|
|
buf[pos] = '^';
|
|
pbuf = &buf[pos] + 1;
|
|
|
|
sprintf(pbuf, "\nparse_error: %s\n", err_text[ps->lasterr]);
|
|
append_filter_string(filter, buf);
|
|
free_page((unsigned long) buf);
|
|
}
|
|
|
|
static inline struct event_filter *event_filter(struct trace_event_file *file)
|
|
{
|
|
return file->filter;
|
|
}
|
|
|
|
/* caller must hold event_mutex */
|
|
void print_event_filter(struct trace_event_file *file, struct trace_seq *s)
|
|
{
|
|
struct event_filter *filter = event_filter(file);
|
|
|
|
if (filter && filter->filter_string)
|
|
trace_seq_printf(s, "%s\n", filter->filter_string);
|
|
else
|
|
trace_seq_puts(s, "none\n");
|
|
}
|
|
|
|
void print_subsystem_event_filter(struct event_subsystem *system,
|
|
struct trace_seq *s)
|
|
{
|
|
struct event_filter *filter;
|
|
|
|
mutex_lock(&event_mutex);
|
|
filter = system->filter;
|
|
if (filter && filter->filter_string)
|
|
trace_seq_printf(s, "%s\n", filter->filter_string);
|
|
else
|
|
trace_seq_puts(s, DEFAULT_SYS_FILTER_MESSAGE "\n");
|
|
mutex_unlock(&event_mutex);
|
|
}
|
|
|
|
static int __alloc_pred_stack(struct pred_stack *stack, int n_preds)
|
|
{
|
|
stack->preds = kcalloc(n_preds + 1, sizeof(*stack->preds), GFP_KERNEL);
|
|
if (!stack->preds)
|
|
return -ENOMEM;
|
|
stack->index = n_preds;
|
|
return 0;
|
|
}
|
|
|
|
static void __free_pred_stack(struct pred_stack *stack)
|
|
{
|
|
kfree(stack->preds);
|
|
stack->index = 0;
|
|
}
|
|
|
|
static int __push_pred_stack(struct pred_stack *stack,
|
|
struct filter_pred *pred)
|
|
{
|
|
int index = stack->index;
|
|
|
|
if (WARN_ON(index == 0))
|
|
return -ENOSPC;
|
|
|
|
stack->preds[--index] = pred;
|
|
stack->index = index;
|
|
return 0;
|
|
}
|
|
|
|
static struct filter_pred *
|
|
__pop_pred_stack(struct pred_stack *stack)
|
|
{
|
|
struct filter_pred *pred;
|
|
int index = stack->index;
|
|
|
|
pred = stack->preds[index++];
|
|
if (!pred)
|
|
return NULL;
|
|
|
|
stack->index = index;
|
|
return pred;
|
|
}
|
|
|
|
static int filter_set_pred(struct event_filter *filter,
|
|
int idx,
|
|
struct pred_stack *stack,
|
|
struct filter_pred *src)
|
|
{
|
|
struct filter_pred *dest = &filter->preds[idx];
|
|
struct filter_pred *left;
|
|
struct filter_pred *right;
|
|
|
|
*dest = *src;
|
|
dest->index = idx;
|
|
|
|
if (dest->op == OP_OR || dest->op == OP_AND) {
|
|
right = __pop_pred_stack(stack);
|
|
left = __pop_pred_stack(stack);
|
|
if (!left || !right)
|
|
return -EINVAL;
|
|
/*
|
|
* If both children can be folded
|
|
* and they are the same op as this op or a leaf,
|
|
* then this op can be folded.
|
|
*/
|
|
if (left->index & FILTER_PRED_FOLD &&
|
|
((left->op == dest->op && !left->not) ||
|
|
left->left == FILTER_PRED_INVALID) &&
|
|
right->index & FILTER_PRED_FOLD &&
|
|
((right->op == dest->op && !right->not) ||
|
|
right->left == FILTER_PRED_INVALID))
|
|
dest->index |= FILTER_PRED_FOLD;
|
|
|
|
dest->left = left->index & ~FILTER_PRED_FOLD;
|
|
dest->right = right->index & ~FILTER_PRED_FOLD;
|
|
left->parent = dest->index & ~FILTER_PRED_FOLD;
|
|
right->parent = dest->index | FILTER_PRED_IS_RIGHT;
|
|
} else {
|
|
/*
|
|
* Make dest->left invalid to be used as a quick
|
|
* way to know this is a leaf node.
|
|
*/
|
|
dest->left = FILTER_PRED_INVALID;
|
|
|
|
/* All leafs allow folding the parent ops. */
|
|
dest->index |= FILTER_PRED_FOLD;
|
|
}
|
|
|
|
return __push_pred_stack(stack, dest);
|
|
}
|
|
|
|
static void __free_preds(struct event_filter *filter)
|
|
{
|
|
int i;
|
|
|
|
if (filter->preds) {
|
|
for (i = 0; i < filter->n_preds; i++)
|
|
kfree(filter->preds[i].ops);
|
|
kfree(filter->preds);
|
|
filter->preds = NULL;
|
|
}
|
|
filter->a_preds = 0;
|
|
filter->n_preds = 0;
|
|
}
|
|
|
|
static void filter_disable(struct trace_event_file *file)
|
|
{
|
|
unsigned long old_flags = file->flags;
|
|
|
|
file->flags &= ~EVENT_FILE_FL_FILTERED;
|
|
|
|
if (old_flags != file->flags)
|
|
trace_buffered_event_disable();
|
|
}
|
|
|
|
static void __free_filter(struct event_filter *filter)
|
|
{
|
|
if (!filter)
|
|
return;
|
|
|
|
__free_preds(filter);
|
|
kfree(filter->filter_string);
|
|
kfree(filter);
|
|
}
|
|
|
|
void free_event_filter(struct event_filter *filter)
|
|
{
|
|
__free_filter(filter);
|
|
}
|
|
|
|
static struct event_filter *__alloc_filter(void)
|
|
{
|
|
struct event_filter *filter;
|
|
|
|
filter = kzalloc(sizeof(*filter), GFP_KERNEL);
|
|
return filter;
|
|
}
|
|
|
|
static int __alloc_preds(struct event_filter *filter, int n_preds)
|
|
{
|
|
struct filter_pred *pred;
|
|
int i;
|
|
|
|
if (filter->preds)
|
|
__free_preds(filter);
|
|
|
|
filter->preds = kcalloc(n_preds, sizeof(*filter->preds), GFP_KERNEL);
|
|
|
|
if (!filter->preds)
|
|
return -ENOMEM;
|
|
|
|
filter->a_preds = n_preds;
|
|
filter->n_preds = 0;
|
|
|
|
for (i = 0; i < n_preds; i++) {
|
|
pred = &filter->preds[i];
|
|
pred->fn = filter_pred_none;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline void __remove_filter(struct trace_event_file *file)
|
|
{
|
|
filter_disable(file);
|
|
remove_filter_string(file->filter);
|
|
}
|
|
|
|
static void filter_free_subsystem_preds(struct trace_subsystem_dir *dir,
|
|
struct trace_array *tr)
|
|
{
|
|
struct trace_event_file *file;
|
|
|
|
list_for_each_entry(file, &tr->events, list) {
|
|
if (file->system != dir)
|
|
continue;
|
|
__remove_filter(file);
|
|
}
|
|
}
|
|
|
|
static inline void __free_subsystem_filter(struct trace_event_file *file)
|
|
{
|
|
__free_filter(file->filter);
|
|
file->filter = NULL;
|
|
}
|
|
|
|
static void filter_free_subsystem_filters(struct trace_subsystem_dir *dir,
|
|
struct trace_array *tr)
|
|
{
|
|
struct trace_event_file *file;
|
|
|
|
list_for_each_entry(file, &tr->events, list) {
|
|
if (file->system != dir)
|
|
continue;
|
|
__free_subsystem_filter(file);
|
|
}
|
|
}
|
|
|
|
static int filter_add_pred(struct filter_parse_state *ps,
|
|
struct event_filter *filter,
|
|
struct filter_pred *pred,
|
|
struct pred_stack *stack)
|
|
{
|
|
int err;
|
|
|
|
if (WARN_ON(filter->n_preds == filter->a_preds)) {
|
|
parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
|
|
return -ENOSPC;
|
|
}
|
|
|
|
err = filter_set_pred(filter, filter->n_preds, stack, pred);
|
|
if (err)
|
|
return err;
|
|
|
|
filter->n_preds++;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int filter_assign_type(const char *type)
|
|
{
|
|
if (strstr(type, "__data_loc") && strstr(type, "char"))
|
|
return FILTER_DYN_STRING;
|
|
|
|
if (strchr(type, '[') && strstr(type, "char"))
|
|
return FILTER_STATIC_STRING;
|
|
|
|
return FILTER_OTHER;
|
|
}
|
|
|
|
static bool is_legal_op(struct ftrace_event_field *field, enum filter_op_ids op)
|
|
{
|
|
if (is_string_field(field) &&
|
|
(op != OP_EQ && op != OP_NE && op != OP_GLOB))
|
|
return false;
|
|
if (!is_string_field(field) && op == OP_GLOB)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static filter_pred_fn_t select_comparison_fn(enum filter_op_ids op,
|
|
int field_size, int field_is_signed)
|
|
{
|
|
filter_pred_fn_t fn = NULL;
|
|
|
|
switch (field_size) {
|
|
case 8:
|
|
if (op == OP_EQ || op == OP_NE)
|
|
fn = filter_pred_64;
|
|
else if (field_is_signed)
|
|
fn = pred_funcs_s64[op - PRED_FUNC_START];
|
|
else
|
|
fn = pred_funcs_u64[op - PRED_FUNC_START];
|
|
break;
|
|
case 4:
|
|
if (op == OP_EQ || op == OP_NE)
|
|
fn = filter_pred_32;
|
|
else if (field_is_signed)
|
|
fn = pred_funcs_s32[op - PRED_FUNC_START];
|
|
else
|
|
fn = pred_funcs_u32[op - PRED_FUNC_START];
|
|
break;
|
|
case 2:
|
|
if (op == OP_EQ || op == OP_NE)
|
|
fn = filter_pred_16;
|
|
else if (field_is_signed)
|
|
fn = pred_funcs_s16[op - PRED_FUNC_START];
|
|
else
|
|
fn = pred_funcs_u16[op - PRED_FUNC_START];
|
|
break;
|
|
case 1:
|
|
if (op == OP_EQ || op == OP_NE)
|
|
fn = filter_pred_8;
|
|
else if (field_is_signed)
|
|
fn = pred_funcs_s8[op - PRED_FUNC_START];
|
|
else
|
|
fn = pred_funcs_u8[op - PRED_FUNC_START];
|
|
break;
|
|
}
|
|
|
|
return fn;
|
|
}
|
|
|
|
static int init_pred(struct filter_parse_state *ps,
|
|
struct ftrace_event_field *field,
|
|
struct filter_pred *pred)
|
|
|
|
{
|
|
filter_pred_fn_t fn = filter_pred_none;
|
|
unsigned long long val;
|
|
int ret;
|
|
|
|
pred->offset = field->offset;
|
|
|
|
if (!is_legal_op(field, pred->op)) {
|
|
parse_error(ps, FILT_ERR_ILLEGAL_FIELD_OP, 0);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (field->filter_type == FILTER_COMM) {
|
|
filter_build_regex(pred);
|
|
fn = filter_pred_comm;
|
|
pred->regex.field_len = TASK_COMM_LEN;
|
|
} else if (is_string_field(field)) {
|
|
filter_build_regex(pred);
|
|
|
|
if (field->filter_type == FILTER_STATIC_STRING) {
|
|
fn = filter_pred_string;
|
|
pred->regex.field_len = field->size;
|
|
} else if (field->filter_type == FILTER_DYN_STRING)
|
|
fn = filter_pred_strloc;
|
|
else
|
|
fn = filter_pred_pchar;
|
|
} else if (is_function_field(field)) {
|
|
if (strcmp(field->name, "ip")) {
|
|
parse_error(ps, FILT_ERR_IP_FIELD_ONLY, 0);
|
|
return -EINVAL;
|
|
}
|
|
} else {
|
|
if (field->is_signed)
|
|
ret = kstrtoll(pred->regex.pattern, 0, &val);
|
|
else
|
|
ret = kstrtoull(pred->regex.pattern, 0, &val);
|
|
if (ret) {
|
|
parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0);
|
|
return -EINVAL;
|
|
}
|
|
pred->val = val;
|
|
|
|
if (field->filter_type == FILTER_CPU)
|
|
fn = filter_pred_cpu;
|
|
else
|
|
fn = select_comparison_fn(pred->op, field->size,
|
|
field->is_signed);
|
|
if (!fn) {
|
|
parse_error(ps, FILT_ERR_INVALID_OP, 0);
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
if (pred->op == OP_NE)
|
|
pred->not ^= 1;
|
|
|
|
pred->fn = fn;
|
|
return 0;
|
|
}
|
|
|
|
static void parse_init(struct filter_parse_state *ps,
|
|
struct filter_op *ops,
|
|
char *infix_string)
|
|
{
|
|
memset(ps, '\0', sizeof(*ps));
|
|
|
|
ps->infix.string = infix_string;
|
|
ps->infix.cnt = strlen(infix_string);
|
|
ps->ops = ops;
|
|
|
|
INIT_LIST_HEAD(&ps->opstack);
|
|
INIT_LIST_HEAD(&ps->postfix);
|
|
}
|
|
|
|
static char infix_next(struct filter_parse_state *ps)
|
|
{
|
|
if (!ps->infix.cnt)
|
|
return 0;
|
|
|
|
ps->infix.cnt--;
|
|
|
|
return ps->infix.string[ps->infix.tail++];
|
|
}
|
|
|
|
static char infix_peek(struct filter_parse_state *ps)
|
|
{
|
|
if (ps->infix.tail == strlen(ps->infix.string))
|
|
return 0;
|
|
|
|
return ps->infix.string[ps->infix.tail];
|
|
}
|
|
|
|
static void infix_advance(struct filter_parse_state *ps)
|
|
{
|
|
if (!ps->infix.cnt)
|
|
return;
|
|
|
|
ps->infix.cnt--;
|
|
ps->infix.tail++;
|
|
}
|
|
|
|
static inline int is_precedence_lower(struct filter_parse_state *ps,
|
|
int a, int b)
|
|
{
|
|
return ps->ops[a].precedence < ps->ops[b].precedence;
|
|
}
|
|
|
|
static inline int is_op_char(struct filter_parse_state *ps, char c)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
|
|
if (ps->ops[i].string[0] == c)
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int infix_get_op(struct filter_parse_state *ps, char firstc)
|
|
{
|
|
char nextc = infix_peek(ps);
|
|
char opstr[3];
|
|
int i;
|
|
|
|
opstr[0] = firstc;
|
|
opstr[1] = nextc;
|
|
opstr[2] = '\0';
|
|
|
|
for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
|
|
if (!strcmp(opstr, ps->ops[i].string)) {
|
|
infix_advance(ps);
|
|
return ps->ops[i].id;
|
|
}
|
|
}
|
|
|
|
opstr[1] = '\0';
|
|
|
|
for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
|
|
if (!strcmp(opstr, ps->ops[i].string))
|
|
return ps->ops[i].id;
|
|
}
|
|
|
|
return OP_NONE;
|
|
}
|
|
|
|
static inline void clear_operand_string(struct filter_parse_state *ps)
|
|
{
|
|
memset(ps->operand.string, '\0', MAX_FILTER_STR_VAL);
|
|
ps->operand.tail = 0;
|
|
}
|
|
|
|
static inline int append_operand_char(struct filter_parse_state *ps, char c)
|
|
{
|
|
if (ps->operand.tail == MAX_FILTER_STR_VAL - 1)
|
|
return -EINVAL;
|
|
|
|
ps->operand.string[ps->operand.tail++] = c;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int filter_opstack_push(struct filter_parse_state *ps,
|
|
enum filter_op_ids op)
|
|
{
|
|
struct opstack_op *opstack_op;
|
|
|
|
opstack_op = kmalloc(sizeof(*opstack_op), GFP_KERNEL);
|
|
if (!opstack_op)
|
|
return -ENOMEM;
|
|
|
|
opstack_op->op = op;
|
|
list_add(&opstack_op->list, &ps->opstack);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int filter_opstack_empty(struct filter_parse_state *ps)
|
|
{
|
|
return list_empty(&ps->opstack);
|
|
}
|
|
|
|
static int filter_opstack_top(struct filter_parse_state *ps)
|
|
{
|
|
struct opstack_op *opstack_op;
|
|
|
|
if (filter_opstack_empty(ps))
|
|
return OP_NONE;
|
|
|
|
opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list);
|
|
|
|
return opstack_op->op;
|
|
}
|
|
|
|
static int filter_opstack_pop(struct filter_parse_state *ps)
|
|
{
|
|
struct opstack_op *opstack_op;
|
|
enum filter_op_ids op;
|
|
|
|
if (filter_opstack_empty(ps))
|
|
return OP_NONE;
|
|
|
|
opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list);
|
|
op = opstack_op->op;
|
|
list_del(&opstack_op->list);
|
|
|
|
kfree(opstack_op);
|
|
|
|
return op;
|
|
}
|
|
|
|
static void filter_opstack_clear(struct filter_parse_state *ps)
|
|
{
|
|
while (!filter_opstack_empty(ps))
|
|
filter_opstack_pop(ps);
|
|
}
|
|
|
|
static char *curr_operand(struct filter_parse_state *ps)
|
|
{
|
|
return ps->operand.string;
|
|
}
|
|
|
|
static int postfix_append_operand(struct filter_parse_state *ps, char *operand)
|
|
{
|
|
struct postfix_elt *elt;
|
|
|
|
elt = kmalloc(sizeof(*elt), GFP_KERNEL);
|
|
if (!elt)
|
|
return -ENOMEM;
|
|
|
|
elt->op = OP_NONE;
|
|
elt->operand = kstrdup(operand, GFP_KERNEL);
|
|
if (!elt->operand) {
|
|
kfree(elt);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
list_add_tail(&elt->list, &ps->postfix);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int postfix_append_op(struct filter_parse_state *ps, enum filter_op_ids op)
|
|
{
|
|
struct postfix_elt *elt;
|
|
|
|
elt = kmalloc(sizeof(*elt), GFP_KERNEL);
|
|
if (!elt)
|
|
return -ENOMEM;
|
|
|
|
elt->op = op;
|
|
elt->operand = NULL;
|
|
|
|
list_add_tail(&elt->list, &ps->postfix);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void postfix_clear(struct filter_parse_state *ps)
|
|
{
|
|
struct postfix_elt *elt;
|
|
|
|
while (!list_empty(&ps->postfix)) {
|
|
elt = list_first_entry(&ps->postfix, struct postfix_elt, list);
|
|
list_del(&elt->list);
|
|
kfree(elt->operand);
|
|
kfree(elt);
|
|
}
|
|
}
|
|
|
|
static int filter_parse(struct filter_parse_state *ps)
|
|
{
|
|
enum filter_op_ids op, top_op;
|
|
int in_string = 0;
|
|
char ch;
|
|
|
|
while ((ch = infix_next(ps))) {
|
|
if (ch == '"') {
|
|
in_string ^= 1;
|
|
continue;
|
|
}
|
|
|
|
if (in_string)
|
|
goto parse_operand;
|
|
|
|
if (isspace(ch))
|
|
continue;
|
|
|
|
if (is_op_char(ps, ch)) {
|
|
op = infix_get_op(ps, ch);
|
|
if (op == OP_NONE) {
|
|
parse_error(ps, FILT_ERR_INVALID_OP, 0);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (strlen(curr_operand(ps))) {
|
|
postfix_append_operand(ps, curr_operand(ps));
|
|
clear_operand_string(ps);
|
|
}
|
|
|
|
while (!filter_opstack_empty(ps)) {
|
|
top_op = filter_opstack_top(ps);
|
|
if (!is_precedence_lower(ps, top_op, op)) {
|
|
top_op = filter_opstack_pop(ps);
|
|
postfix_append_op(ps, top_op);
|
|
continue;
|
|
}
|
|
break;
|
|
}
|
|
|
|
filter_opstack_push(ps, op);
|
|
continue;
|
|
}
|
|
|
|
if (ch == '(') {
|
|
filter_opstack_push(ps, OP_OPEN_PAREN);
|
|
continue;
|
|
}
|
|
|
|
if (ch == ')') {
|
|
if (strlen(curr_operand(ps))) {
|
|
postfix_append_operand(ps, curr_operand(ps));
|
|
clear_operand_string(ps);
|
|
}
|
|
|
|
top_op = filter_opstack_pop(ps);
|
|
while (top_op != OP_NONE) {
|
|
if (top_op == OP_OPEN_PAREN)
|
|
break;
|
|
postfix_append_op(ps, top_op);
|
|
top_op = filter_opstack_pop(ps);
|
|
}
|
|
if (top_op == OP_NONE) {
|
|
parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0);
|
|
return -EINVAL;
|
|
}
|
|
continue;
|
|
}
|
|
parse_operand:
|
|
if (append_operand_char(ps, ch)) {
|
|
parse_error(ps, FILT_ERR_OPERAND_TOO_LONG, 0);
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
if (strlen(curr_operand(ps)))
|
|
postfix_append_operand(ps, curr_operand(ps));
|
|
|
|
while (!filter_opstack_empty(ps)) {
|
|
top_op = filter_opstack_pop(ps);
|
|
if (top_op == OP_NONE)
|
|
break;
|
|
if (top_op == OP_OPEN_PAREN) {
|
|
parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0);
|
|
return -EINVAL;
|
|
}
|
|
postfix_append_op(ps, top_op);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct filter_pred *create_pred(struct filter_parse_state *ps,
|
|
struct trace_event_call *call,
|
|
enum filter_op_ids op,
|
|
char *operand1, char *operand2)
|
|
{
|
|
struct ftrace_event_field *field;
|
|
static struct filter_pred pred;
|
|
|
|
memset(&pred, 0, sizeof(pred));
|
|
pred.op = op;
|
|
|
|
if (op == OP_AND || op == OP_OR)
|
|
return &pred;
|
|
|
|
if (!operand1 || !operand2) {
|
|
parse_error(ps, FILT_ERR_MISSING_FIELD, 0);
|
|
return NULL;
|
|
}
|
|
|
|
field = trace_find_event_field(call, operand1);
|
|
if (!field) {
|
|
parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0);
|
|
return NULL;
|
|
}
|
|
|
|
strcpy(pred.regex.pattern, operand2);
|
|
pred.regex.len = strlen(pred.regex.pattern);
|
|
pred.field = field;
|
|
return init_pred(ps, field, &pred) ? NULL : &pred;
|
|
}
|
|
|
|
static int check_preds(struct filter_parse_state *ps)
|
|
{
|
|
int n_normal_preds = 0, n_logical_preds = 0;
|
|
struct postfix_elt *elt;
|
|
int cnt = 0;
|
|
|
|
list_for_each_entry(elt, &ps->postfix, list) {
|
|
if (elt->op == OP_NONE) {
|
|
cnt++;
|
|
continue;
|
|
}
|
|
|
|
if (elt->op == OP_AND || elt->op == OP_OR) {
|
|
n_logical_preds++;
|
|
cnt--;
|
|
continue;
|
|
}
|
|
if (elt->op != OP_NOT)
|
|
cnt--;
|
|
n_normal_preds++;
|
|
/* all ops should have operands */
|
|
if (cnt < 0)
|
|
break;
|
|
}
|
|
|
|
if (cnt != 1 || !n_normal_preds || n_logical_preds >= n_normal_preds) {
|
|
parse_error(ps, FILT_ERR_INVALID_FILTER, 0);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int count_preds(struct filter_parse_state *ps)
|
|
{
|
|
struct postfix_elt *elt;
|
|
int n_preds = 0;
|
|
|
|
list_for_each_entry(elt, &ps->postfix, list) {
|
|
if (elt->op == OP_NONE)
|
|
continue;
|
|
n_preds++;
|
|
}
|
|
|
|
return n_preds;
|
|
}
|
|
|
|
struct check_pred_data {
|
|
int count;
|
|
int max;
|
|
};
|
|
|
|
static int check_pred_tree_cb(enum move_type move, struct filter_pred *pred,
|
|
int *err, void *data)
|
|
{
|
|
struct check_pred_data *d = data;
|
|
|
|
if (WARN_ON(d->count++ > d->max)) {
|
|
*err = -EINVAL;
|
|
return WALK_PRED_ABORT;
|
|
}
|
|
return WALK_PRED_DEFAULT;
|
|
}
|
|
|
|
/*
|
|
* The tree is walked at filtering of an event. If the tree is not correctly
|
|
* built, it may cause an infinite loop. Check here that the tree does
|
|
* indeed terminate.
|
|
*/
|
|
static int check_pred_tree(struct event_filter *filter,
|
|
struct filter_pred *root)
|
|
{
|
|
struct check_pred_data data = {
|
|
/*
|
|
* The max that we can hit a node is three times.
|
|
* Once going down, once coming up from left, and
|
|
* once coming up from right. This is more than enough
|
|
* since leafs are only hit a single time.
|
|
*/
|
|
.max = 3 * filter->n_preds,
|
|
.count = 0,
|
|
};
|
|
|
|
return walk_pred_tree(filter->preds, root,
|
|
check_pred_tree_cb, &data);
|
|
}
|
|
|
|
static int count_leafs_cb(enum move_type move, struct filter_pred *pred,
|
|
int *err, void *data)
|
|
{
|
|
int *count = data;
|
|
|
|
if ((move == MOVE_DOWN) &&
|
|
(pred->left == FILTER_PRED_INVALID))
|
|
(*count)++;
|
|
|
|
return WALK_PRED_DEFAULT;
|
|
}
|
|
|
|
static int count_leafs(struct filter_pred *preds, struct filter_pred *root)
|
|
{
|
|
int count = 0, ret;
|
|
|
|
ret = walk_pred_tree(preds, root, count_leafs_cb, &count);
|
|
WARN_ON(ret);
|
|
return count;
|
|
}
|
|
|
|
struct fold_pred_data {
|
|
struct filter_pred *root;
|
|
int count;
|
|
int children;
|
|
};
|
|
|
|
static int fold_pred_cb(enum move_type move, struct filter_pred *pred,
|
|
int *err, void *data)
|
|
{
|
|
struct fold_pred_data *d = data;
|
|
struct filter_pred *root = d->root;
|
|
|
|
if (move != MOVE_DOWN)
|
|
return WALK_PRED_DEFAULT;
|
|
if (pred->left != FILTER_PRED_INVALID)
|
|
return WALK_PRED_DEFAULT;
|
|
|
|
if (WARN_ON(d->count == d->children)) {
|
|
*err = -EINVAL;
|
|
return WALK_PRED_ABORT;
|
|
}
|
|
|
|
pred->index &= ~FILTER_PRED_FOLD;
|
|
root->ops[d->count++] = pred->index;
|
|
return WALK_PRED_DEFAULT;
|
|
}
|
|
|
|
static int fold_pred(struct filter_pred *preds, struct filter_pred *root)
|
|
{
|
|
struct fold_pred_data data = {
|
|
.root = root,
|
|
.count = 0,
|
|
};
|
|
int children;
|
|
|
|
/* No need to keep the fold flag */
|
|
root->index &= ~FILTER_PRED_FOLD;
|
|
|
|
/* If the root is a leaf then do nothing */
|
|
if (root->left == FILTER_PRED_INVALID)
|
|
return 0;
|
|
|
|
/* count the children */
|
|
children = count_leafs(preds, &preds[root->left]);
|
|
children += count_leafs(preds, &preds[root->right]);
|
|
|
|
root->ops = kcalloc(children, sizeof(*root->ops), GFP_KERNEL);
|
|
if (!root->ops)
|
|
return -ENOMEM;
|
|
|
|
root->val = children;
|
|
data.children = children;
|
|
return walk_pred_tree(preds, root, fold_pred_cb, &data);
|
|
}
|
|
|
|
static int fold_pred_tree_cb(enum move_type move, struct filter_pred *pred,
|
|
int *err, void *data)
|
|
{
|
|
struct filter_pred *preds = data;
|
|
|
|
if (move != MOVE_DOWN)
|
|
return WALK_PRED_DEFAULT;
|
|
if (!(pred->index & FILTER_PRED_FOLD))
|
|
return WALK_PRED_DEFAULT;
|
|
|
|
*err = fold_pred(preds, pred);
|
|
if (*err)
|
|
return WALK_PRED_ABORT;
|
|
|
|
/* eveyrhing below is folded, continue with parent */
|
|
return WALK_PRED_PARENT;
|
|
}
|
|
|
|
/*
|
|
* To optimize the processing of the ops, if we have several "ors" or
|
|
* "ands" together, we can put them in an array and process them all
|
|
* together speeding up the filter logic.
|
|
*/
|
|
static int fold_pred_tree(struct event_filter *filter,
|
|
struct filter_pred *root)
|
|
{
|
|
return walk_pred_tree(filter->preds, root, fold_pred_tree_cb,
|
|
filter->preds);
|
|
}
|
|
|
|
static int replace_preds(struct trace_event_call *call,
|
|
struct event_filter *filter,
|
|
struct filter_parse_state *ps,
|
|
bool dry_run)
|
|
{
|
|
char *operand1 = NULL, *operand2 = NULL;
|
|
struct filter_pred *pred;
|
|
struct filter_pred *root;
|
|
struct postfix_elt *elt;
|
|
struct pred_stack stack = { }; /* init to NULL */
|
|
int err;
|
|
int n_preds = 0;
|
|
|
|
n_preds = count_preds(ps);
|
|
if (n_preds >= MAX_FILTER_PRED) {
|
|
parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
|
|
return -ENOSPC;
|
|
}
|
|
|
|
err = check_preds(ps);
|
|
if (err)
|
|
return err;
|
|
|
|
if (!dry_run) {
|
|
err = __alloc_pred_stack(&stack, n_preds);
|
|
if (err)
|
|
return err;
|
|
err = __alloc_preds(filter, n_preds);
|
|
if (err)
|
|
goto fail;
|
|
}
|
|
|
|
n_preds = 0;
|
|
list_for_each_entry(elt, &ps->postfix, list) {
|
|
if (elt->op == OP_NONE) {
|
|
if (!operand1)
|
|
operand1 = elt->operand;
|
|
else if (!operand2)
|
|
operand2 = elt->operand;
|
|
else {
|
|
parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0);
|
|
err = -EINVAL;
|
|
goto fail;
|
|
}
|
|
continue;
|
|
}
|
|
|
|
if (elt->op == OP_NOT) {
|
|
if (!n_preds || operand1 || operand2) {
|
|
parse_error(ps, FILT_ERR_ILLEGAL_NOT_OP, 0);
|
|
err = -EINVAL;
|
|
goto fail;
|
|
}
|
|
if (!dry_run)
|
|
filter->preds[n_preds - 1].not ^= 1;
|
|
continue;
|
|
}
|
|
|
|
if (WARN_ON(n_preds++ == MAX_FILTER_PRED)) {
|
|
parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
|
|
err = -ENOSPC;
|
|
goto fail;
|
|
}
|
|
|
|
pred = create_pred(ps, call, elt->op, operand1, operand2);
|
|
if (!pred) {
|
|
err = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
if (!dry_run) {
|
|
err = filter_add_pred(ps, filter, pred, &stack);
|
|
if (err)
|
|
goto fail;
|
|
}
|
|
|
|
operand1 = operand2 = NULL;
|
|
}
|
|
|
|
if (!dry_run) {
|
|
/* We should have one item left on the stack */
|
|
pred = __pop_pred_stack(&stack);
|
|
if (!pred)
|
|
return -EINVAL;
|
|
/* This item is where we start from in matching */
|
|
root = pred;
|
|
/* Make sure the stack is empty */
|
|
pred = __pop_pred_stack(&stack);
|
|
if (WARN_ON(pred)) {
|
|
err = -EINVAL;
|
|
filter->root = NULL;
|
|
goto fail;
|
|
}
|
|
err = check_pred_tree(filter, root);
|
|
if (err)
|
|
goto fail;
|
|
|
|
/* Optimize the tree */
|
|
err = fold_pred_tree(filter, root);
|
|
if (err)
|
|
goto fail;
|
|
|
|
/* We don't set root until we know it works */
|
|
barrier();
|
|
filter->root = root;
|
|
}
|
|
|
|
err = 0;
|
|
fail:
|
|
__free_pred_stack(&stack);
|
|
return err;
|
|
}
|
|
|
|
static inline void event_set_filtered_flag(struct trace_event_file *file)
|
|
{
|
|
unsigned long old_flags = file->flags;
|
|
|
|
file->flags |= EVENT_FILE_FL_FILTERED;
|
|
|
|
if (old_flags != file->flags)
|
|
trace_buffered_event_enable();
|
|
}
|
|
|
|
static inline void event_set_filter(struct trace_event_file *file,
|
|
struct event_filter *filter)
|
|
{
|
|
rcu_assign_pointer(file->filter, filter);
|
|
}
|
|
|
|
static inline void event_clear_filter(struct trace_event_file *file)
|
|
{
|
|
RCU_INIT_POINTER(file->filter, NULL);
|
|
}
|
|
|
|
static inline void
|
|
event_set_no_set_filter_flag(struct trace_event_file *file)
|
|
{
|
|
file->flags |= EVENT_FILE_FL_NO_SET_FILTER;
|
|
}
|
|
|
|
static inline void
|
|
event_clear_no_set_filter_flag(struct trace_event_file *file)
|
|
{
|
|
file->flags &= ~EVENT_FILE_FL_NO_SET_FILTER;
|
|
}
|
|
|
|
static inline bool
|
|
event_no_set_filter_flag(struct trace_event_file *file)
|
|
{
|
|
if (file->flags & EVENT_FILE_FL_NO_SET_FILTER)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
struct filter_list {
|
|
struct list_head list;
|
|
struct event_filter *filter;
|
|
};
|
|
|
|
static int replace_system_preds(struct trace_subsystem_dir *dir,
|
|
struct trace_array *tr,
|
|
struct filter_parse_state *ps,
|
|
char *filter_string)
|
|
{
|
|
struct trace_event_file *file;
|
|
struct filter_list *filter_item;
|
|
struct filter_list *tmp;
|
|
LIST_HEAD(filter_list);
|
|
bool fail = true;
|
|
int err;
|
|
|
|
list_for_each_entry(file, &tr->events, list) {
|
|
if (file->system != dir)
|
|
continue;
|
|
|
|
/*
|
|
* Try to see if the filter can be applied
|
|
* (filter arg is ignored on dry_run)
|
|
*/
|
|
err = replace_preds(file->event_call, NULL, ps, true);
|
|
if (err)
|
|
event_set_no_set_filter_flag(file);
|
|
else
|
|
event_clear_no_set_filter_flag(file);
|
|
}
|
|
|
|
list_for_each_entry(file, &tr->events, list) {
|
|
struct event_filter *filter;
|
|
|
|
if (file->system != dir)
|
|
continue;
|
|
|
|
if (event_no_set_filter_flag(file))
|
|
continue;
|
|
|
|
filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL);
|
|
if (!filter_item)
|
|
goto fail_mem;
|
|
|
|
list_add_tail(&filter_item->list, &filter_list);
|
|
|
|
filter_item->filter = __alloc_filter();
|
|
if (!filter_item->filter)
|
|
goto fail_mem;
|
|
filter = filter_item->filter;
|
|
|
|
/* Can only fail on no memory */
|
|
err = replace_filter_string(filter, filter_string);
|
|
if (err)
|
|
goto fail_mem;
|
|
|
|
err = replace_preds(file->event_call, filter, ps, false);
|
|
if (err) {
|
|
filter_disable(file);
|
|
parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
|
|
append_filter_err(ps, filter);
|
|
} else
|
|
event_set_filtered_flag(file);
|
|
/*
|
|
* Regardless of if this returned an error, we still
|
|
* replace the filter for the call.
|
|
*/
|
|
filter = event_filter(file);
|
|
event_set_filter(file, filter_item->filter);
|
|
filter_item->filter = filter;
|
|
|
|
fail = false;
|
|
}
|
|
|
|
if (fail)
|
|
goto fail;
|
|
|
|
/*
|
|
* The calls can still be using the old filters.
|
|
* Do a synchronize_sched() to ensure all calls are
|
|
* done with them before we free them.
|
|
*/
|
|
synchronize_sched();
|
|
list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
|
|
__free_filter(filter_item->filter);
|
|
list_del(&filter_item->list);
|
|
kfree(filter_item);
|
|
}
|
|
return 0;
|
|
fail:
|
|
/* No call succeeded */
|
|
list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
|
|
list_del(&filter_item->list);
|
|
kfree(filter_item);
|
|
}
|
|
parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
|
|
return -EINVAL;
|
|
fail_mem:
|
|
/* If any call succeeded, we still need to sync */
|
|
if (!fail)
|
|
synchronize_sched();
|
|
list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
|
|
__free_filter(filter_item->filter);
|
|
list_del(&filter_item->list);
|
|
kfree(filter_item);
|
|
}
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static int create_filter_start(char *filter_str, bool set_str,
|
|
struct filter_parse_state **psp,
|
|
struct event_filter **filterp)
|
|
{
|
|
struct event_filter *filter;
|
|
struct filter_parse_state *ps = NULL;
|
|
int err = 0;
|
|
|
|
WARN_ON_ONCE(*psp || *filterp);
|
|
|
|
/* allocate everything, and if any fails, free all and fail */
|
|
filter = __alloc_filter();
|
|
if (filter && set_str)
|
|
err = replace_filter_string(filter, filter_str);
|
|
|
|
ps = kzalloc(sizeof(*ps), GFP_KERNEL);
|
|
|
|
if (!filter || !ps || err) {
|
|
kfree(ps);
|
|
__free_filter(filter);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* we're committed to creating a new filter */
|
|
*filterp = filter;
|
|
*psp = ps;
|
|
|
|
parse_init(ps, filter_ops, filter_str);
|
|
err = filter_parse(ps);
|
|
if (err && set_str)
|
|
append_filter_err(ps, filter);
|
|
return err;
|
|
}
|
|
|
|
static void create_filter_finish(struct filter_parse_state *ps)
|
|
{
|
|
if (ps) {
|
|
filter_opstack_clear(ps);
|
|
postfix_clear(ps);
|
|
kfree(ps);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* create_filter - create a filter for a trace_event_call
|
|
* @call: trace_event_call to create a filter for
|
|
* @filter_str: filter string
|
|
* @set_str: remember @filter_str and enable detailed error in filter
|
|
* @filterp: out param for created filter (always updated on return)
|
|
*
|
|
* Creates a filter for @call with @filter_str. If @set_str is %true,
|
|
* @filter_str is copied and recorded in the new filter.
|
|
*
|
|
* On success, returns 0 and *@filterp points to the new filter. On
|
|
* failure, returns -errno and *@filterp may point to %NULL or to a new
|
|
* filter. In the latter case, the returned filter contains error
|
|
* information if @set_str is %true and the caller is responsible for
|
|
* freeing it.
|
|
*/
|
|
static int create_filter(struct trace_event_call *call,
|
|
char *filter_str, bool set_str,
|
|
struct event_filter **filterp)
|
|
{
|
|
struct event_filter *filter = NULL;
|
|
struct filter_parse_state *ps = NULL;
|
|
int err;
|
|
|
|
err = create_filter_start(filter_str, set_str, &ps, &filter);
|
|
if (!err) {
|
|
err = replace_preds(call, filter, ps, false);
|
|
if (err && set_str)
|
|
append_filter_err(ps, filter);
|
|
}
|
|
if (err && !set_str) {
|
|
free_event_filter(filter);
|
|
filter = NULL;
|
|
}
|
|
create_filter_finish(ps);
|
|
|
|
*filterp = filter;
|
|
return err;
|
|
}
|
|
|
|
int create_event_filter(struct trace_event_call *call,
|
|
char *filter_str, bool set_str,
|
|
struct event_filter **filterp)
|
|
{
|
|
return create_filter(call, filter_str, set_str, filterp);
|
|
}
|
|
|
|
/**
|
|
* create_system_filter - create a filter for an event_subsystem
|
|
* @system: event_subsystem to create a filter for
|
|
* @filter_str: filter string
|
|
* @filterp: out param for created filter (always updated on return)
|
|
*
|
|
* Identical to create_filter() except that it creates a subsystem filter
|
|
* and always remembers @filter_str.
|
|
*/
|
|
static int create_system_filter(struct trace_subsystem_dir *dir,
|
|
struct trace_array *tr,
|
|
char *filter_str, struct event_filter **filterp)
|
|
{
|
|
struct event_filter *filter = NULL;
|
|
struct filter_parse_state *ps = NULL;
|
|
int err;
|
|
|
|
err = create_filter_start(filter_str, true, &ps, &filter);
|
|
if (!err) {
|
|
err = replace_system_preds(dir, tr, ps, filter_str);
|
|
if (!err) {
|
|
/* System filters just show a default message */
|
|
kfree(filter->filter_string);
|
|
filter->filter_string = NULL;
|
|
} else {
|
|
append_filter_err(ps, filter);
|
|
}
|
|
}
|
|
create_filter_finish(ps);
|
|
|
|
*filterp = filter;
|
|
return err;
|
|
}
|
|
|
|
/* caller must hold event_mutex */
|
|
int apply_event_filter(struct trace_event_file *file, char *filter_string)
|
|
{
|
|
struct trace_event_call *call = file->event_call;
|
|
struct event_filter *filter;
|
|
int err;
|
|
|
|
if (!strcmp(strstrip(filter_string), "0")) {
|
|
filter_disable(file);
|
|
filter = event_filter(file);
|
|
|
|
if (!filter)
|
|
return 0;
|
|
|
|
event_clear_filter(file);
|
|
|
|
/* Make sure the filter is not being used */
|
|
synchronize_sched();
|
|
__free_filter(filter);
|
|
|
|
return 0;
|
|
}
|
|
|
|
err = create_filter(call, filter_string, true, &filter);
|
|
|
|
/*
|
|
* Always swap the call filter with the new filter
|
|
* even if there was an error. If there was an error
|
|
* in the filter, we disable the filter and show the error
|
|
* string
|
|
*/
|
|
if (filter) {
|
|
struct event_filter *tmp;
|
|
|
|
tmp = event_filter(file);
|
|
if (!err)
|
|
event_set_filtered_flag(file);
|
|
else
|
|
filter_disable(file);
|
|
|
|
event_set_filter(file, filter);
|
|
|
|
if (tmp) {
|
|
/* Make sure the call is done with the filter */
|
|
synchronize_sched();
|
|
__free_filter(tmp);
|
|
}
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
|
|
char *filter_string)
|
|
{
|
|
struct event_subsystem *system = dir->subsystem;
|
|
struct trace_array *tr = dir->tr;
|
|
struct event_filter *filter;
|
|
int err = 0;
|
|
|
|
mutex_lock(&event_mutex);
|
|
|
|
/* Make sure the system still has events */
|
|
if (!dir->nr_events) {
|
|
err = -ENODEV;
|
|
goto out_unlock;
|
|
}
|
|
|
|
if (!strcmp(strstrip(filter_string), "0")) {
|
|
filter_free_subsystem_preds(dir, tr);
|
|
remove_filter_string(system->filter);
|
|
filter = system->filter;
|
|
system->filter = NULL;
|
|
/* Ensure all filters are no longer used */
|
|
synchronize_sched();
|
|
filter_free_subsystem_filters(dir, tr);
|
|
__free_filter(filter);
|
|
goto out_unlock;
|
|
}
|
|
|
|
err = create_system_filter(dir, tr, filter_string, &filter);
|
|
if (filter) {
|
|
/*
|
|
* No event actually uses the system filter
|
|
* we can free it without synchronize_sched().
|
|
*/
|
|
__free_filter(system->filter);
|
|
system->filter = filter;
|
|
}
|
|
out_unlock:
|
|
mutex_unlock(&event_mutex);
|
|
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
|
|
void ftrace_profile_free_filter(struct perf_event *event)
|
|
{
|
|
struct event_filter *filter = event->filter;
|
|
|
|
event->filter = NULL;
|
|
__free_filter(filter);
|
|
}
|
|
|
|
struct function_filter_data {
|
|
struct ftrace_ops *ops;
|
|
int first_filter;
|
|
int first_notrace;
|
|
};
|
|
|
|
#ifdef CONFIG_FUNCTION_TRACER
|
|
static char **
|
|
ftrace_function_filter_re(char *buf, int len, int *count)
|
|
{
|
|
char *str, **re;
|
|
|
|
str = kstrndup(buf, len, GFP_KERNEL);
|
|
if (!str)
|
|
return NULL;
|
|
|
|
/*
|
|
* The argv_split function takes white space
|
|
* as a separator, so convert ',' into spaces.
|
|
*/
|
|
strreplace(str, ',', ' ');
|
|
|
|
re = argv_split(GFP_KERNEL, str, count);
|
|
kfree(str);
|
|
return re;
|
|
}
|
|
|
|
static int ftrace_function_set_regexp(struct ftrace_ops *ops, int filter,
|
|
int reset, char *re, int len)
|
|
{
|
|
int ret;
|
|
|
|
if (filter)
|
|
ret = ftrace_set_filter(ops, re, len, reset);
|
|
else
|
|
ret = ftrace_set_notrace(ops, re, len, reset);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int __ftrace_function_set_filter(int filter, char *buf, int len,
|
|
struct function_filter_data *data)
|
|
{
|
|
int i, re_cnt, ret = -EINVAL;
|
|
int *reset;
|
|
char **re;
|
|
|
|
reset = filter ? &data->first_filter : &data->first_notrace;
|
|
|
|
/*
|
|
* The 'ip' field could have multiple filters set, separated
|
|
* either by space or comma. We first cut the filter and apply
|
|
* all pieces separatelly.
|
|
*/
|
|
re = ftrace_function_filter_re(buf, len, &re_cnt);
|
|
if (!re)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < re_cnt; i++) {
|
|
ret = ftrace_function_set_regexp(data->ops, filter, *reset,
|
|
re[i], strlen(re[i]));
|
|
if (ret)
|
|
break;
|
|
|
|
if (*reset)
|
|
*reset = 0;
|
|
}
|
|
|
|
argv_free(re);
|
|
return ret;
|
|
}
|
|
|
|
static int ftrace_function_check_pred(struct filter_pred *pred, int leaf)
|
|
{
|
|
struct ftrace_event_field *field = pred->field;
|
|
|
|
if (leaf) {
|
|
/*
|
|
* Check the leaf predicate for function trace, verify:
|
|
* - only '==' and '!=' is used
|
|
* - the 'ip' field is used
|
|
*/
|
|
if ((pred->op != OP_EQ) && (pred->op != OP_NE))
|
|
return -EINVAL;
|
|
|
|
if (strcmp(field->name, "ip"))
|
|
return -EINVAL;
|
|
} else {
|
|
/*
|
|
* Check the non leaf predicate for function trace, verify:
|
|
* - only '||' is used
|
|
*/
|
|
if (pred->op != OP_OR)
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ftrace_function_set_filter_cb(enum move_type move,
|
|
struct filter_pred *pred,
|
|
int *err, void *data)
|
|
{
|
|
/* Checking the node is valid for function trace. */
|
|
if ((move != MOVE_DOWN) ||
|
|
(pred->left != FILTER_PRED_INVALID)) {
|
|
*err = ftrace_function_check_pred(pred, 0);
|
|
} else {
|
|
*err = ftrace_function_check_pred(pred, 1);
|
|
if (*err)
|
|
return WALK_PRED_ABORT;
|
|
|
|
*err = __ftrace_function_set_filter(pred->op == OP_EQ,
|
|
pred->regex.pattern,
|
|
pred->regex.len,
|
|
data);
|
|
}
|
|
|
|
return (*err) ? WALK_PRED_ABORT : WALK_PRED_DEFAULT;
|
|
}
|
|
|
|
static int ftrace_function_set_filter(struct perf_event *event,
|
|
struct event_filter *filter)
|
|
{
|
|
struct function_filter_data data = {
|
|
.first_filter = 1,
|
|
.first_notrace = 1,
|
|
.ops = &event->ftrace_ops,
|
|
};
|
|
|
|
return walk_pred_tree(filter->preds, filter->root,
|
|
ftrace_function_set_filter_cb, &data);
|
|
}
|
|
#else
|
|
static int ftrace_function_set_filter(struct perf_event *event,
|
|
struct event_filter *filter)
|
|
{
|
|
return -ENODEV;
|
|
}
|
|
#endif /* CONFIG_FUNCTION_TRACER */
|
|
|
|
int ftrace_profile_set_filter(struct perf_event *event, int event_id,
|
|
char *filter_str)
|
|
{
|
|
int err;
|
|
struct event_filter *filter;
|
|
struct trace_event_call *call;
|
|
|
|
mutex_lock(&event_mutex);
|
|
|
|
call = event->tp_event;
|
|
|
|
err = -EINVAL;
|
|
if (!call)
|
|
goto out_unlock;
|
|
|
|
err = -EEXIST;
|
|
if (event->filter)
|
|
goto out_unlock;
|
|
|
|
err = create_filter(call, filter_str, false, &filter);
|
|
if (err)
|
|
goto free_filter;
|
|
|
|
if (ftrace_event_is_function(call))
|
|
err = ftrace_function_set_filter(event, filter);
|
|
else
|
|
event->filter = filter;
|
|
|
|
free_filter:
|
|
if (err || ftrace_event_is_function(call))
|
|
__free_filter(filter);
|
|
|
|
out_unlock:
|
|
mutex_unlock(&event_mutex);
|
|
|
|
return err;
|
|
}
|
|
|
|
#endif /* CONFIG_PERF_EVENTS */
|
|
|
|
#ifdef CONFIG_FTRACE_STARTUP_TEST
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/tracepoint.h>
|
|
|
|
#define CREATE_TRACE_POINTS
|
|
#include "trace_events_filter_test.h"
|
|
|
|
#define DATA_REC(m, va, vb, vc, vd, ve, vf, vg, vh, nvisit) \
|
|
{ \
|
|
.filter = FILTER, \
|
|
.rec = { .a = va, .b = vb, .c = vc, .d = vd, \
|
|
.e = ve, .f = vf, .g = vg, .h = vh }, \
|
|
.match = m, \
|
|
.not_visited = nvisit, \
|
|
}
|
|
#define YES 1
|
|
#define NO 0
|
|
|
|
static struct test_filter_data_t {
|
|
char *filter;
|
|
struct trace_event_raw_ftrace_test_filter rec;
|
|
int match;
|
|
char *not_visited;
|
|
} test_filter_data[] = {
|
|
#define FILTER "a == 1 && b == 1 && c == 1 && d == 1 && " \
|
|
"e == 1 && f == 1 && g == 1 && h == 1"
|
|
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, ""),
|
|
DATA_REC(NO, 0, 1, 1, 1, 1, 1, 1, 1, "bcdefgh"),
|
|
DATA_REC(NO, 1, 1, 1, 1, 1, 1, 1, 0, ""),
|
|
#undef FILTER
|
|
#define FILTER "a == 1 || b == 1 || c == 1 || d == 1 || " \
|
|
"e == 1 || f == 1 || g == 1 || h == 1"
|
|
DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 0, ""),
|
|
DATA_REC(YES, 0, 0, 0, 0, 0, 0, 0, 1, ""),
|
|
DATA_REC(YES, 1, 0, 0, 0, 0, 0, 0, 0, "bcdefgh"),
|
|
#undef FILTER
|
|
#define FILTER "(a == 1 || b == 1) && (c == 1 || d == 1) && " \
|
|
"(e == 1 || f == 1) && (g == 1 || h == 1)"
|
|
DATA_REC(NO, 0, 0, 1, 1, 1, 1, 1, 1, "dfh"),
|
|
DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""),
|
|
DATA_REC(YES, 1, 0, 1, 0, 0, 1, 0, 1, "bd"),
|
|
DATA_REC(NO, 1, 0, 1, 0, 0, 1, 0, 0, "bd"),
|
|
#undef FILTER
|
|
#define FILTER "(a == 1 && b == 1) || (c == 1 && d == 1) || " \
|
|
"(e == 1 && f == 1) || (g == 1 && h == 1)"
|
|
DATA_REC(YES, 1, 0, 1, 1, 1, 1, 1, 1, "efgh"),
|
|
DATA_REC(YES, 0, 0, 0, 0, 0, 0, 1, 1, ""),
|
|
DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 1, ""),
|
|
#undef FILTER
|
|
#define FILTER "(a == 1 && b == 1) && (c == 1 && d == 1) && " \
|
|
"(e == 1 && f == 1) || (g == 1 && h == 1)"
|
|
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 0, "gh"),
|
|
DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 1, ""),
|
|
DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, ""),
|
|
#undef FILTER
|
|
#define FILTER "((a == 1 || b == 1) || (c == 1 || d == 1) || " \
|
|
"(e == 1 || f == 1)) && (g == 1 || h == 1)"
|
|
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 1, "bcdef"),
|
|
DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 0, ""),
|
|
DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, "h"),
|
|
#undef FILTER
|
|
#define FILTER "((((((((a == 1) && (b == 1)) || (c == 1)) && (d == 1)) || " \
|
|
"(e == 1)) && (f == 1)) || (g == 1)) && (h == 1))"
|
|
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "ceg"),
|
|
DATA_REC(NO, 0, 1, 0, 1, 0, 1, 0, 1, ""),
|
|
DATA_REC(NO, 1, 0, 1, 0, 1, 0, 1, 0, ""),
|
|
#undef FILTER
|
|
#define FILTER "((((((((a == 1) || (b == 1)) && (c == 1)) || (d == 1)) && " \
|
|
"(e == 1)) || (f == 1)) && (g == 1)) || (h == 1))"
|
|
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "bdfh"),
|
|
DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""),
|
|
DATA_REC(YES, 1, 0, 1, 0, 1, 0, 1, 0, "bdfh"),
|
|
};
|
|
|
|
#undef DATA_REC
|
|
#undef FILTER
|
|
#undef YES
|
|
#undef NO
|
|
|
|
#define DATA_CNT (sizeof(test_filter_data)/sizeof(struct test_filter_data_t))
|
|
|
|
static int test_pred_visited;
|
|
|
|
static int test_pred_visited_fn(struct filter_pred *pred, void *event)
|
|
{
|
|
struct ftrace_event_field *field = pred->field;
|
|
|
|
test_pred_visited = 1;
|
|
printk(KERN_INFO "\npred visited %s\n", field->name);
|
|
return 1;
|
|
}
|
|
|
|
static int test_walk_pred_cb(enum move_type move, struct filter_pred *pred,
|
|
int *err, void *data)
|
|
{
|
|
char *fields = data;
|
|
|
|
if ((move == MOVE_DOWN) &&
|
|
(pred->left == FILTER_PRED_INVALID)) {
|
|
struct ftrace_event_field *field = pred->field;
|
|
|
|
if (!field) {
|
|
WARN(1, "all leafs should have field defined");
|
|
return WALK_PRED_DEFAULT;
|
|
}
|
|
if (!strchr(fields, *field->name))
|
|
return WALK_PRED_DEFAULT;
|
|
|
|
WARN_ON(!pred->fn);
|
|
pred->fn = test_pred_visited_fn;
|
|
}
|
|
return WALK_PRED_DEFAULT;
|
|
}
|
|
|
|
static __init int ftrace_test_event_filter(void)
|
|
{
|
|
int i;
|
|
|
|
printk(KERN_INFO "Testing ftrace filter: ");
|
|
|
|
for (i = 0; i < DATA_CNT; i++) {
|
|
struct event_filter *filter = NULL;
|
|
struct test_filter_data_t *d = &test_filter_data[i];
|
|
int err;
|
|
|
|
err = create_filter(&event_ftrace_test_filter, d->filter,
|
|
false, &filter);
|
|
if (err) {
|
|
printk(KERN_INFO
|
|
"Failed to get filter for '%s', err %d\n",
|
|
d->filter, err);
|
|
__free_filter(filter);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* The preemption disabling is not really needed for self
|
|
* tests, but the rcu dereference will complain without it.
|
|
*/
|
|
preempt_disable();
|
|
if (*d->not_visited)
|
|
walk_pred_tree(filter->preds, filter->root,
|
|
test_walk_pred_cb,
|
|
d->not_visited);
|
|
|
|
test_pred_visited = 0;
|
|
err = filter_match_preds(filter, &d->rec);
|
|
preempt_enable();
|
|
|
|
__free_filter(filter);
|
|
|
|
if (test_pred_visited) {
|
|
printk(KERN_INFO
|
|
"Failed, unwanted pred visited for filter %s\n",
|
|
d->filter);
|
|
break;
|
|
}
|
|
|
|
if (err != d->match) {
|
|
printk(KERN_INFO
|
|
"Failed to match filter '%s', expected %d\n",
|
|
d->filter, d->match);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (i == DATA_CNT)
|
|
printk(KERN_CONT "OK\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
late_initcall(ftrace_test_event_filter);
|
|
|
|
#endif /* CONFIG_FTRACE_STARTUP_TEST */
|