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提交 80765597 编写于 作者: S Steven Rostedt (VMware)
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tracing: Rewrite filter logic to be simpler and faster 

Al Viro reviewed the filter logic of ftrace trace events and found it to be
very troubling. It creates a binary tree based on the logic operators and
walks it during tracing. He sent myself and Tom Zanussi a long explanation
(and formal proof) of how to do the string parsing better and end up with a
program array that can be simply iterated to come up with the correct
results.

I took his ideas and his pseudo code and rewrote the filter logic based on
them. In doing so, I was able to remove a lot of code, and have a much more
condensed filter logic in the process. I wrote a very long comment
describing the methadology that Al proposed in my own words. For more info
on how this works, read the comment above predicate_parse().
Suggested-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
上级 478325f1
隐藏空白更改
内联 并排
Showing with 1054 addition and 1272 deletion
kernel/trace/trace.h
浏览文件 @ 80765597
......@@ -1216,12 +1216,11 @@ struct ftrace_event_field {
int is_signed;
};
struct prog_entry;
struct event_filter {
int n_preds; /* Number assigned */
int a_preds; /* allocated */
struct filter_pred __rcu *preds;
struct filter_pred __rcu *root;
char *filter_string;
struct prog_entry __rcu *prog;
char *filter_string;
};
struct event_subsystem {
......@@ -1413,12 +1412,8 @@ struct filter_pred {
unsigned short *ops;
struct ftrace_event_field *field;
int offset;
int not;
int not;
int op;
unsigned short index;
unsigned short parent;
unsigned short left;
unsigned short right;
};
static inline bool is_string_field(struct ftrace_event_field *field)
......
kernel/trace/trace_events_filter.c
浏览文件 @ 80765597
......@@ -33,60 +33,52 @@
"# Only events with the given fields will be affected.\n" \
"# If no events are modified, an error message will be displayed here"
/* Due to token parsing '<=' must be before '<' and '>=' must be before '>' */
#define OPS \
C( OP_OR, "||", 1 ), \
C( OP_AND, "&&", 2 ), \
C( OP_GLOB, "~", 4 ), \
C( OP_NE, "!=", 4 ), \
C( OP_EQ, "==", 4 ), \
C( OP_LT, "<", 5 ), \
C( OP_LE, "<=", 5 ), \
C( OP_GT, ">", 5 ), \
C( OP_GE, ">=", 5 ), \
C( OP_BAND, "&", 6 ), \
C( OP_NOT, "!", 6 ), \
C( OP_NONE, "OP_NONE", 0 ), \
C( OP_OPEN_PAREN, "(", 0 ), \
C( OP_MAX, NULL, 0 )
C( OP_GLOB, "~" ), \
C( OP_NE, "!=" ), \
C( OP_EQ, "==" ), \
C( OP_LE, "<=" ), \
C( OP_LT, "<" ), \
C( OP_GE, ">=" ), \
C( OP_GT, ">" ), \
C( OP_BAND, "&" ), \
C( OP_MAX, NULL )
#undef C
#define C(a, b, c) a
#define C(a, b) a
enum filter_op_ids { OPS };
struct filter_op {
int id;
char *string;
int precedence;
};
#undef C
#define C(a, b, c) { a, b, c }
#define C(a, b) b
static struct filter_op filter_ops[] = { OPS };
static const char * ops[] = { OPS };
/*
* pred functions are OP_LT, OP_LE, OP_GT, OP_GE, and OP_BAND
* pred functions are OP_LE, OP_LT, OP_GE, OP_GT, and OP_BAND
* pred_funcs_##type below must match the order of them above.
*/
#define PRED_FUNC_START OP_LT
#define PRED_FUNC_START OP_LE
#define PRED_FUNC_MAX (OP_BAND - PRED_FUNC_START)
#define ERRORS \
C( NONE, "No error"), \
C( INVALID_OP, "Invalid operator"), \
C( UNBALANCED_PAREN, "Unbalanced parens"), \
C( TOO_MANY_OPERANDS, "Too many operands"), \
C( OPERAND_TOO_LONG, "Operand too long"), \
C( FIELD_NOT_FOUND, "Field not found"), \
C( ILLEGAL_FIELD_OP, "Illegal operation for field type"), \
C( ILLEGAL_INTVAL, "Illegal integer value"), \
C( BAD_SUBSYS_FILTER, "Couldn't find or set field in one of a subsystem's events"), \
C( TOO_MANY_PREDS, "Too many terms in predicate expression"), \
C( MISSING_FIELD, "Missing field name and/or value"), \
C( INVALID_FILTER, "Meaningless filter expression"), \
C( IP_FIELD_ONLY, "Only 'ip' field is supported for function trace"), \
C( ILLEGAL_NOT_OP, "Illegal use of '!'"),
C(NONE, "No error"), \
C(INVALID_OP, "Invalid operator"), \
C(TOO_MANY_OPEN, "Too many '('"), \
C(TOO_MANY_CLOSE, "Too few '('"), \
C(MISSING_QUOTE, "Missing matching quote"), \
C(OPERAND_TOO_LONG, "Operand too long"), \
C(EXPECT_STRING, "Expecting string field"), \
C(EXPECT_DIGIT, "Expecting numeric field"), \
C(ILLEGAL_FIELD_OP, "Illegal operation for field type"), \
C(FIELD_NOT_FOUND, "Field not found"), \
C(ILLEGAL_INTVAL, "Illegal integer value"), \
C(BAD_SUBSYS_FILTER, "Couldn't find or set field in one of a subsystem's events"), \
C(TOO_MANY_PREDS, "Too many terms in predicate expression"), \
C(INVALID_FILTER, "Meaningless filter expression"), \
C(IP_FIELD_ONLY, "Only 'ip' field is supported for function trace"), \
C(INVALID_VALUE, "Invalid value (did you forget quotes)?"),
#undef C
#define C(a, b) FILT_ERR_##a
......@@ -98,84 +90,535 @@ enum { ERRORS };
static char *err_text[] = { ERRORS };
struct opstack_op {
enum filter_op_ids op;
struct list_head list;
};
/* Called after a '!' character but "!=" and "!~" are not "not"s */
static bool is_not(const char *str)
{
switch (str[1]) {
case '=':
case '~':
return false;
}
return true;
}
struct postfix_elt {
enum filter_op_ids op;
char *operand;
struct list_head list;
/**
* prog_entry - a singe entry in the filter program
* @target: Index to jump to on a branch (actually one minus the index)
* @when_to_branch: The value of the result of the predicate to do a branch
* @pred: The predicate to execute.
*/
struct prog_entry {
int target;
int when_to_branch;
struct filter_pred *pred;
};
struct filter_parse_state {
struct filter_op *ops;
struct list_head opstack;
struct list_head postfix;
/**
* update_preds- assign a program entry a label target
* @prog: The program array
* @N: The index of the current entry in @prog
* @when_to_branch: What to assign a program entry for its branch condition
*
* The program entry at @N has a target that points to the index of a program
* entry that can have its target and when_to_branch fields updated.
* Update the current program entry denoted by index @N target field to be
* that of the updated entry. This will denote the entry to update if
* we are processing an "||" after an "&&"
*/
static void update_preds(struct prog_entry *prog, int N, int invert)
{
int t, s;
t = prog[N].target;
s = prog[t].target;
prog[t].when_to_branch = invert;
prog[t].target = N;
prog[N].target = s;
}
struct filter_parse_error {
int lasterr;
int lasterr_pos;
struct {
char *string;
unsigned int cnt;
unsigned int tail;
} infix;
struct {
char string[MAX_FILTER_STR_VAL];
int pos;
unsigned int tail;
} operand;
};
struct pred_stack {
struct filter_pred **preds;
int index;
static void parse_error(struct filter_parse_error *pe, int err, int pos)
{
pe->lasterr = err;
pe->lasterr_pos = pos;
}
typedef int (*parse_pred_fn)(const char *str, void *data, int pos,
struct filter_parse_error *pe,
struct filter_pred **pred);
enum {
INVERT = 1,
PROCESS_AND = 2,
PROCESS_OR = 4,
};
/* If not of not match is equal to not of not, then it is a match */
/*
* Without going into a formal proof, this explains the method that is used in
* parsing the logical expressions.
*
* For example, if we have: "a && !(!b || (c && g)) || d || e && !f"
* The first pass will convert it into the following program:
*
* n1: r=a; l1: if (!r) goto l4;
* n2: r=b; l2: if (!r) goto l4;
* n3: r=c; r=!r; l3: if (r) goto l4;
* n4: r=g; r=!r; l4: if (r) goto l5;
* n5: r=d; l5: if (r) goto T
* n6: r=e; l6: if (!r) goto l7;
* n7: r=f; r=!r; l7: if (!r) goto F
* T: return TRUE
* F: return FALSE
*
* To do this, we use a data structure to represent each of the above
* predicate and conditions that has:
*
* predicate, when_to_branch, invert, target
*
* The "predicate" will hold the function to determine the result "r".
* The "when_to_branch" denotes what "r" should be if a branch is to be taken
* "&&" would contain "!r" or (0) and "||" would contain "r" or (1).
* The "invert" holds whether the value should be reversed before testing.
* The "target" contains the label "l#" to jump to.
*
* A stack is created to hold values when parentheses are used.
*
* To simplify the logic, the labels will start at 0 and not 1.
*
* The possible invert values are 1 and 0. The number of "!"s that are in scope
* before the predicate determines the invert value, if the number is odd then
* the invert value is 1 and 0 otherwise. This means the invert value only
* needs to be toggled when a new "!" is introduced compared to what is stored
* on the stack, where parentheses were used.
*
* The top of the stack and "invert" are initialized to zero.
*
* ** FIRST PASS **
*
* #1 A loop through all the tokens is done:
*
* #2 If the token is an "(", the stack is push, and the current stack value
* gets the current invert value, and the loop continues to the next token.
* The top of the stack saves the "invert" value to keep track of what
* the current inversion is. As "!(a && !b || c)" would require all
* predicates being affected separately by the "!" before the parentheses.
* And that would end up being equivalent to "(!a || b) && !c"
*
* #3 If the token is an "!", the current "invert" value gets inverted, and
* the loop continues. Note, if the next token is a predicate, then
* this "invert" value is only valid for the current program entry,
* and does not affect other predicates later on.
*
* The only other acceptable token is the predicate string.
*
* #4 A new entry into the program is added saving: the predicate and the
* current value of "invert". The target is currently assigned to the
* previous program index (this will not be its final value).
*
* #5 We now enter another loop and look at the next token. The only valid
* tokens are ")", "&&", "||" or end of the input string "\0".
*
* #6 The invert variable is reset to the current value saved on the top of
* the stack.
*
* #7 The top of the stack holds not only the current invert value, but also
* if a "&&" or "||" needs to be processed. Note, the "&&" takes higher
* precedence than "||". That is "a && b || c && d" is equivalent to
* "(a && b) || (c && d)". Thus the first thing to do is to see if "&&" needs
* to be processed. This is the case if an "&&" was the last token. If it was
* then we call update_preds(). This takes the program, the current index in
* the program, and the current value of "invert". More will be described
* below about this function.
*
* #8 If the next token is "&&" then we set a flag in the top of the stack
* that denotes that "&&" needs to be processed, break out of this loop
* and continue with the outer loop.
*
* #9 Otherwise, if a "||" needs to be processed then update_preds() is called.
* This is called with the program, the current index in the program, but
* this time with an inverted value of "invert" (that is !invert). This is
* because the value taken will become the "when_to_branch" value of the
* program.
* Note, this is called when the next token is not an "&&". As stated before,
* "&&" takes higher precedence, and "||" should not be processed yet if the
* next logical operation is "&&".
*
* #10 If the next token is "||" then we set a flag in the top of the stack
* that denotes that "||" needs to be processed, break out of this loop
* and continue with the outer loop.
*
* #11 If this is the end of the input string "\0" then we break out of both
* loops.
*
* #12 Otherwise, the next token is ")", where we pop the stack and continue
* this inner loop.
*
* Now to discuss the update_pred() function, as that is key to the setting up
* of the program. Remember the "target" of the program is initialized to the
* previous index and not the "l" label. The target holds the index into the
* program that gets affected by the operand. Thus if we have something like
* "a || b && c", when we process "a" the target will be "-1" (undefined).
* When we process "b", its target is "0", which is the index of "a", as that's
* the predicate that is affected by "||". But because the next token after "b"
* is "&&" we don't call update_preds(). Instead continue to "c". As the
* next token after "c" is not "&&" but the end of input, we first process the
* "&&" by calling update_preds() for the "&&" then we process the "||" by
* callin updates_preds() with the values for processing "||".
*
* What does that mean? What update_preds() does is to first save the "target"
* of the program entry indexed by the current program entry's "target"
* (remember the "target" is initialized to previous program entry), and then
* sets that "target" to the current index which represents the label "l#".
* That entry's "when_to_branch" is set to the value passed in (the "invert"
* or "!invert"). Then it sets the current program entry's target to the saved
* "target" value (the old value of the program that had its "target" updated
* to the label).
*
* Looking back at "a || b && c", we have the following steps:
* "a" - prog[0] = { "a", X, -1 } // pred, when_to_branch, target
* "||" - flag that we need to process "||"; continue outer loop
* "b" - prog[1] = { "b", X, 0 }
* "&&" - flag that we need to process "&&"; continue outer loop
* (Notice we did not process "||")
* "c" - prog[2] = { "c", X, 1 }
* update_preds(prog, 2, 0); // invert = 0 as we are processing "&&"
* t = prog[2].target; // t = 1
* s = prog[t].target; // s = 0
* prog[t].target = 2; // Set target to "l2"
* prog[t].when_to_branch = 0;
* prog[2].target = s;
* update_preds(prog, 2, 1); // invert = 1 as we are now processing "||"
* t = prog[2].target; // t = 0
* s = prog[t].target; // s = -1
* prog[t].target = 2; // Set target to "l2"
* prog[t].when_to_branch = 1;
* prog[2].target = s;
*
* #13 Which brings us to the final step of the first pass, which is to set
* the last program entry's when_to_branch and target, which will be
* when_to_branch = 0; target = N; ( the label after the program entry after
* the last program entry processed above).
*
* If we denote "TRUE" to be the entry after the last program entry processed,
* and "FALSE" the program entry after that, we are now done with the first
* pass.
*
* Making the above "a || b && c" have a progam of:
* prog[0] = { "a", 1, 2 }
* prog[1] = { "b", 0, 2 }
* prog[2] = { "c", 0, 3 }
*
* Which translates into:
* n0: r = a; l0: if (r) goto l2;
* n1: r = b; l1: if (!r) goto l2;
* n2: r = c; l2: if (!r) goto l3; // Which is the same as "goto F;"
* T: return TRUE; l3:
* F: return FALSE
*
* Although, after the first pass, the program is correct, it is
* inefficient. The simple sample of "a || b && c" could be easily been
* converted into:
* n0: r = a; if (r) goto T
* n1: r = b; if (!r) goto F
* n2: r = c; if (!r) goto F
* T: return TRUE;
* F: return FALSE;
*
* The First Pass is over the input string. The next too passes are over
* the program itself.
*
* ** SECOND PASS **
*
* Which brings us to the second pass. If a jump to a label has the
* same condition as that label, it can instead jump to its target.
* The original example of "a && !(!b || (c && g)) || d || e && !f"
* where the first pass gives us:
*
* n1: r=a; l1: if (!r) goto l4;
* n2: r=b; l2: if (!r) goto l4;
* n3: r=c; r=!r; l3: if (r) goto l4;
* n4: r=g; r=!r; l4: if (r) goto l5;
* n5: r=d; l5: if (r) goto T
* n6: r=e; l6: if (!r) goto l7;
* n7: r=f; r=!r; l7: if (!r) goto F:
* T: return TRUE;
* F: return FALSE
*
* We can see that "l3: if (r) goto l4;" and at l4, we have "if (r) goto l5;".
* And "l5: if (r) goto T", we could optimize this by converting l3 and l4
* to go directly to T. To accomplish this, we start from the last
* entry in the program and work our way back. If the target of the entry
* has the same "when_to_branch" then we could use that entry's target.
* Doing this, the above would end up as:
*
* n1: r=a; l1: if (!r) goto l4;
* n2: r=b; l2: if (!r) goto l4;
* n3: r=c; r=!r; l3: if (r) goto T;
* n4: r=g; r=!r; l4: if (r) goto T;
* n5: r=d; l5: if (r) goto T;
* n6: r=e; l6: if (!r) goto F;
* n7: r=f; r=!r; l7: if (!r) goto F;
* T: return TRUE
* F: return FALSE
*
* In that same pass, if the "when_to_branch" doesn't match, we can simply
* go to the program entry after the label. That is, "l2: if (!r) goto l4;"
* where "l4: if (r) goto T;", then we can convert l2 to be:
* "l2: if (!r) goto n5;".
*
* This will have the second pass give us:
* n1: r=a; l1: if (!r) goto n5;
* n2: r=b; l2: if (!r) goto n5;
* n3: r=c; r=!r; l3: if (r) goto T;
* n4: r=g; r=!r; l4: if (r) goto T;
* n5: r=d; l5: if (r) goto T
* n6: r=e; l6: if (!r) goto F;
* n7: r=f; r=!r; l7: if (!r) goto F
* T: return TRUE
* F: return FALSE
*
* Notice, all the "l#" labels are no longer used, and they can now
* be discarded.
*
* ** THIRD PASS **
*
* For the third pass we deal with the inverts. As they simply just
* make the "when_to_branch" get inverted, a simple loop over the
* program to that does: "when_to_branch ^= invert;" will do the
* job, leaving us with:
* n1: r=a; if (!r) goto n5;
* n2: r=b; if (!r) goto n5;
* n3: r=c: if (!r) goto T;
* n4: r=g; if (!r) goto T;
* n5: r=d; if (r) goto T
* n6: r=e; if (!r) goto F;
* n7: r=f; if (r) goto F
* T: return TRUE
* F: return FALSE
*
* As "r = a; if (!r) goto n5;" is obviously the same as
* "if (!a) goto n5;" without doing anything we can interperate the
* program as:
* n1: if (!a) goto n5;
* n2: if (!b) goto n5;
* n3: if (!c) goto T;
* n4: if (!g) goto T;
* n5: if (d) goto T
* n6: if (!e) goto F;
* n7: if (f) goto F
* T: return TRUE
* F: return FALSE
*
* Since the inverts are discarded at the end, there's no reason to store
* them in the program array (and waste memory). A separate array to hold
* the inverts is used and freed at the end.
*/
static struct prog_entry *
predicate_parse(const char *str, int nr_parens, int nr_preds,
parse_pred_fn parse_pred, void *data,
struct filter_parse_error *pe)
{
struct prog_entry *prog_stack;
struct prog_entry *prog;
const char *ptr = str;
char *inverts = NULL;
int *op_stack;
int *top;
int invert = 0;
int ret = -ENOMEM;
int len;
int N = 0;
int i;
nr_preds += 2; /* For TRUE and FALSE */
op_stack = kmalloc(sizeof(*op_stack) * nr_parens, GFP_KERNEL);
if (!op_stack)
return ERR_PTR(-ENOMEM);
prog_stack = kmalloc(sizeof(*prog_stack) * nr_preds, GFP_KERNEL);
if (!prog_stack) {
parse_error(pe, -ENOMEM, 0);
goto out_free;
}
inverts = kmalloc(sizeof(*inverts) * nr_preds, GFP_KERNEL);
if (!inverts) {
parse_error(pe, -ENOMEM, 0);
goto out_free;
}
top = op_stack;
prog = prog_stack;
*top = 0;
/* First pass */
while (*ptr) { /* #1 */
const char *next = ptr++;
if (isspace(*next))
continue;
switch (*next) {
case '(': /* #2 */
if (top - op_stack > nr_parens)
return ERR_PTR(-EINVAL);
*(++top) = invert;
continue;
case '!': /* #3 */
if (!is_not(next))
break;
invert = !invert;
continue;
}
if (N >= nr_preds) {
parse_error(pe, FILT_ERR_TOO_MANY_PREDS, next - str);
goto out_free;
}
inverts[N] = invert; /* #4 */
prog[N].target = N-1;
len = parse_pred(next, data, ptr - str, pe, &prog[N].pred);
if (len < 0) {
ret = len;
goto out_free;
}
ptr = next + len;
N++;
ret = -1;
while (1) { /* #5 */
next = ptr++;
if (isspace(*next))
continue;
switch (*next) {
case ')':
case '\0':
break;
case '&':
case '|':
if (next[1] == next[0]) {
ptr++;
break;
}
default:
parse_error(pe, FILT_ERR_TOO_MANY_PREDS,
next - str);
goto out_free;
}
invert = *top & INVERT;
if (*top & PROCESS_AND) { /* #7 */
update_preds(prog, N - 1, invert);
*top &= ~PROCESS_AND;
}
if (*next == '&') { /* #8 */
*top |= PROCESS_AND;
break;
}
if (*top & PROCESS_OR) { /* #9 */
update_preds(prog, N - 1, !invert);
*top &= ~PROCESS_OR;
}
if (*next == '|') { /* #10 */
*top |= PROCESS_OR;
break;
}
if (!*next) /* #11 */
goto out;
if (top == op_stack) {
ret = -1;
/* Too few '(' */
parse_error(pe, FILT_ERR_TOO_MANY_CLOSE, ptr - str);
goto out_free;
}
top--; /* #12 */
}
}
out:
if (top != op_stack) {
/* Too many '(' */
parse_error(pe, FILT_ERR_TOO_MANY_OPEN, ptr - str);
goto out_free;
}
prog[N].pred = NULL; /* #13 */
prog[N].target = 1; /* TRUE */
prog[N+1].pred = NULL;
prog[N+1].target = 0; /* FALSE */
prog[N-1].target = N;
prog[N-1].when_to_branch = false;
/* Second Pass */
for (i = N-1 ; i--; ) {
int target = prog[i].target;
if (prog[i].when_to_branch == prog[target].when_to_branch)
prog[i].target = prog[target].target;
}
/* Third Pass */
for (i = 0; i < N; i++) {
invert = inverts[i] ^ prog[i].when_to_branch;
prog[i].when_to_branch = invert;
/* Make sure the program always moves forward */
if (WARN_ON(prog[i].target <= i)) {
ret = -EINVAL;
goto out_free;
}
}
return prog;
out_free:
kfree(op_stack);
kfree(prog_stack);
kfree(inverts);
return ERR_PTR(ret);
}
#define DEFINE_COMPARISON_PRED(type) \
static int filter_pred_LT_##type(struct filter_pred *pred, void *event) \
{ \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
int match = (*addr < val); \
return !!match == !pred->not; \
return *addr < val; \
} \
static int filter_pred_LE_##type(struct filter_pred *pred, void *event) \
{ \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
int match = (*addr <= val); \
return !!match == !pred->not; \
return *addr <= val; \
} \
static int filter_pred_GT_##type(struct filter_pred *pred, void *event) \
{ \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
int match = (*addr > val); \
return !!match == !pred->not; \
return *addr > val; \
} \
static int filter_pred_GE_##type(struct filter_pred *pred, void *event) \
{ \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
int match = (*addr >= val); \
return !!match == !pred->not; \
return *addr >= val; \
} \
static int filter_pred_BAND_##type(struct filter_pred *pred, void *event) \
{ \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
int match = !!(*addr & val); \
return match == !pred->not; \
return !!(*addr & val); \
} \
static const filter_pred_fn_t pred_funcs_##type[] = { \
filter_pred_LT_##type, \
filter_pred_LE_##type, \
filter_pred_GT_##type, \
filter_pred_LT_##type, \
filter_pred_GE_##type, \
filter_pred_GT_##type, \
filter_pred_BAND_##type, \
};
......@@ -261,44 +704,36 @@ static int filter_pred_strloc(struct filter_pred *pred, void *event)
static int filter_pred_cpu(struct filter_pred *pred, void *event)
{
int cpu, cmp;
int match = 0;
cpu = raw_smp_processor_id();
cmp = pred->val;
switch (pred->op) {
case OP_EQ:
match = cpu == cmp;
break;
return cpu == cmp;
case OP_NE:
return cpu != cmp;
case OP_LT:
match = cpu < cmp;
break;
return cpu < cmp;
case OP_LE:
match = cpu <= cmp;
break;
return cpu <= cmp;
case OP_GT:
match = cpu > cmp;
break;
return cpu > cmp;
case OP_GE:
match = cpu >= cmp;
break;
return cpu >= cmp;
default:
break;
return 0;
}
return !!match == !pred->not;
}
/* Filter predicate for COMM. */
static int filter_pred_comm(struct filter_pred *pred, void *event)
{
int cmp, match;
int cmp;
cmp = pred->regex.match(current->comm, &pred->regex,
pred->regex.field_len);
match = cmp ^ pred->not;
return match;
TASK_COMM_LEN);
return cmp ^ pred->not;
}
static int filter_pred_none(struct filter_pred *pred, void *event)
......@@ -355,6 +790,7 @@ static int regex_match_glob(char *str, struct regex *r, int len __maybe_unused)
return 1;
return 0;
}
/**
* filter_parse_regex - parse a basic regex
* @buff: the raw regex
......@@ -415,10 +851,9 @@ static void filter_build_regex(struct filter_pred *pred)
struct regex *r = &pred->regex;
char *search;
enum regex_type type = MATCH_FULL;
int not = 0;
if (pred->op == OP_GLOB) {
type = filter_parse_regex(r->pattern, r->len, &search, &not);
type = filter_parse_regex(r->pattern, r->len, &search, &pred->not);
r->len = strlen(search);
memmove(r->pattern, search, r->len+1);
}
......@@ -440,210 +875,32 @@ static void filter_build_regex(struct filter_pred *pred)
r->match = regex_match_glob;
break;
}
pred->not ^= not;
}
enum move_type {
MOVE_DOWN,
MOVE_UP_FROM_LEFT,
MOVE_UP_FROM_RIGHT
};
static struct filter_pred *
get_pred_parent(struct filter_pred *pred, struct filter_pred *preds,
int index, enum move_type *move)
{
if (pred->parent & FILTER_PRED_IS_RIGHT)
*move = MOVE_UP_FROM_RIGHT;
else
*move = MOVE_UP_FROM_LEFT;
pred = &preds[pred->parent & ~FILTER_PRED_IS_RIGHT];
return pred;
}
enum walk_return {
WALK_PRED_ABORT,
WALK_PRED_PARENT,
WALK_PRED_DEFAULT,
};
typedef int (*filter_pred_walkcb_t) (enum move_type move,
struct filter_pred *pred,
int *err, void *data);
static int walk_pred_tree(struct filter_pred *preds,
struct filter_pred *root,
filter_pred_walkcb_t cb, void *data)
{
struct filter_pred *pred = root;
enum move_type move = MOVE_DOWN;
int done = 0;
if (!preds)
return -EINVAL;
do {
int err = 0, ret;
ret = cb(move, pred, &err, data);
if (ret == WALK_PRED_ABORT)
return err;
if (ret == WALK_PRED_PARENT)
goto get_parent;
switch (move) {
case MOVE_DOWN:
if (pred->left != FILTER_PRED_INVALID) {
pred = &preds[pred->left];
continue;
}
goto get_parent;
case MOVE_UP_FROM_LEFT:
pred = &preds[pred->right];
move = MOVE_DOWN;
continue;
case MOVE_UP_FROM_RIGHT:
get_parent:
if (pred == root)
break;
pred = get_pred_parent(pred, preds,
pred->parent,
&move);
continue;
}
done = 1;
} while (!done);
/* We are fine. */
return 0;
}
/*
* 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;
struct prog_entry *prog;
int i;
/* no filter is considered a match */
if (!filter)
return 1;
n_preds = filter->n_preds;
if (!n_preds)
prog = rcu_dereference_sched(filter->prog);
if (!prog)
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;
for (i = 0; prog[i].pred; i++) {
struct filter_pred *pred = prog[i].pred;
int match = pred->fn(pred, rec);
if (match == prog[i].when_to_branch)
i = prog[i].target;
}
return prog[i].target;
}
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)
......@@ -653,11 +910,11 @@ static void remove_filter_string(struct event_filter *filter)
filter->filter_string = NULL;
}
static void append_filter_err(struct filter_parse_state *ps,
static void append_filter_err(struct filter_parse_error *pe,
struct event_filter *filter)
{
struct trace_seq *s;
int pos = ps->lasterr_pos;
int pos = pe->lasterr_pos;
char *buf;
int len;
......@@ -671,11 +928,19 @@ static void append_filter_err(struct filter_parse_state *ps,
len = strlen(filter->filter_string);
if (pos > len)
len = pos;
pos = len;
/* indexing is off by one */
if (pos)
pos++;
trace_seq_puts(s, filter->filter_string);
trace_seq_printf(s, "\n%*s", pos, "^");
trace_seq_printf(s, "\nparse_error: %s\n", err_text[ps->lasterr]);
if (pe->lasterr > 0) {
trace_seq_printf(s, "\n%*s", pos, "^");
trace_seq_printf(s, "\nparse_error: %s\n", err_text[pe->lasterr]);
} else {
trace_seq_printf(s, "\nError: (%d)\n", pe->lasterr);
}
trace_seq_putc(s, 0);
buf = kmemdup_nul(s->buffer, s->seq.len, GFP_KERNEL);
if (buf) {
......@@ -715,108 +980,18 @@ void print_subsystem_event_filter(struct event_subsystem *system,
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)
static void free_prog(struct event_filter *filter)
{
struct prog_entry *prog;
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;
prog = rcu_access_pointer(filter->prog);
if (!prog)
return;
for (i = 0; prog[i].pred; i++)
kfree(prog[i].pred);
kfree(prog);
}
static void filter_disable(struct trace_event_file *file)
......@@ -834,7 +1009,7 @@ static void __free_filter(struct event_filter *filter)
if (!filter)
return;
__free_preds(filter);
free_prog(filter);
kfree(filter->filter_string);
kfree(filter);
}
......@@ -844,30 +1019,6 @@ void free_event_filter(struct event_filter *filter)
__free_filter(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);
......@@ -898,812 +1049,466 @@ static void filter_free_subsystem_filters(struct trace_subsystem_dir *dir,
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;
int pred_func_index = -1;
switch (op) {
case OP_EQ:
case OP_NE:
break;
default:
if (WARN_ON_ONCE(op < PRED_FUNC_START))
return NULL;
pred_func_index = op - PRED_FUNC_START;
if (WARN_ON_ONCE(pred_func_index > PRED_FUNC_MAX))
return NULL;
}
switch (field_size) {
case 8:
if (pred_func_index < 0)
fn = filter_pred_64;
else if (field_is_signed)
fn = pred_funcs_s64[pred_func_index];
else
fn = pred_funcs_u64[pred_func_index];
break;
case 4:
if (pred_func_index < 0)
fn = filter_pred_32;
else if (field_is_signed)
fn = pred_funcs_s32[pred_func_index];
else
fn = pred_funcs_u32[pred_func_index];
break;
case 2:
if (pred_func_index < 0)
fn = filter_pred_16;
else if (field_is_signed)
fn = pred_funcs_s16[pred_func_index];
else
fn = pred_funcs_u16[pred_func_index];
break;
case 1:
if (pred_func_index < 0)
fn = filter_pred_8;
else if (field_is_signed)
fn = pred_funcs_s8[pred_func_index];
else
fn = pred_funcs_u8[pred_func_index];
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;
}
if (file->system != dir)
continue;
}
parse_operand:
if (append_operand_char(ps, ch)) {
parse_error(ps, FILT_ERR_OPERAND_TOO_LONG, 0);
return -EINVAL;
}
__free_subsystem_filter(file);
}
}
if (strlen(curr_operand(ps)))
postfix_append_operand(ps, curr_operand(ps));
int filter_assign_type(const char *type)
{
if (strstr(type, "__data_loc") && strstr(type, "char"))
return FILTER_DYN_STRING;
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);
}
if (strchr(type, '[') && strstr(type, "char"))
return FILTER_STATIC_STRING;
return 0;
return FILTER_OTHER;
}
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)
static filter_pred_fn_t select_comparison_fn(enum filter_op_ids op,
int field_size, int field_is_signed)
{
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;
filter_pred_fn_t fn = NULL;
int pred_func_index = -1;
if (!operand1 || !operand2) {
parse_error(ps, FILT_ERR_MISSING_FIELD, 0);
return NULL;
switch (op) {
case OP_EQ:
case OP_NE:
break;
default:
if (WARN_ON_ONCE(op < PRED_FUNC_START))
return NULL;
pred_func_index = op - PRED_FUNC_START;
if (WARN_ON_ONCE(pred_func_index > PRED_FUNC_MAX))
return NULL;
}
field = trace_find_event_field(call, operand1);
if (!field) {
parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0);
return NULL;
switch (field_size) {
case 8:
if (pred_func_index < 0)
fn = filter_pred_64;
else if (field_is_signed)
fn = pred_funcs_s64[pred_func_index];
else
fn = pred_funcs_u64[pred_func_index];
break;
case 4:
if (pred_func_index < 0)
fn = filter_pred_32;
else if (field_is_signed)
fn = pred_funcs_s32[pred_func_index];
else
fn = pred_funcs_u32[pred_func_index];
break;
case 2:
if (pred_func_index < 0)
fn = filter_pred_16;
else if (field_is_signed)
fn = pred_funcs_s16[pred_func_index];
else
fn = pred_funcs_u16[pred_func_index];
break;
case 1:
if (pred_func_index < 0)
fn = filter_pred_8;
else if (field_is_signed)
fn = pred_funcs_s8[pred_func_index];
else
fn = pred_funcs_u8[pred_func_index];
break;
}
strcpy(pred.regex.pattern, operand2);
pred.regex.len = strlen(pred.regex.pattern);
pred.field = field;
return init_pred(ps, field, &pred) ? NULL : &pred;
return fn;
}
static int check_preds(struct filter_parse_state *ps)
/* Called when a predicate is encountered by predicate_parse() */
static int parse_pred(const char *str, void *data,
int pos, struct filter_parse_error *pe,
struct filter_pred **pred_ptr)
{
int n_normal_preds = 0, n_logical_preds = 0;
struct postfix_elt *elt;
int cnt = 0;
struct trace_event_call *call = data;
struct ftrace_event_field *field;
struct filter_pred *pred = NULL;
char num_buf[24]; /* Big enough to hold an address */
char *field_name;
char q;
u64 val;
int len;
int ret;
int op;
int s;
int i = 0;
list_for_each_entry(elt, &ps->postfix, list) {
if (elt->op == OP_NONE) {
cnt++;
continue;
}
/* First find the field to associate to */
while (isspace(str[i]))
i++;
s = i;
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;
}
while (isalnum(str[i]) || str[i] == '_')
i++;
len = i - s;
if (!len)
return -1;
field_name = kmemdup_nul(str + s, len, GFP_KERNEL);
if (!field_name)
return -ENOMEM;
/* Make sure that the field exists */
if (cnt != 1 || !n_normal_preds || n_logical_preds >= n_normal_preds) {
parse_error(ps, FILT_ERR_INVALID_FILTER, 0);
field = trace_find_event_field(call, field_name);
kfree(field_name);
if (!field) {
parse_error(pe, FILT_ERR_FIELD_NOT_FOUND, pos + i);
return -EINVAL;
}
return 0;
}
while (isspace(str[i]))
i++;
static int count_preds(struct filter_parse_state *ps)
{
struct postfix_elt *elt;
int n_preds = 0;
/* Make sure this op is supported */
for (op = 0; ops[op]; op++) {
/* This is why '<=' must come before '<' in ops[] */
if (strncmp(str + i, ops[op], strlen(ops[op])) == 0)
break;
}
list_for_each_entry(elt, &ps->postfix, list) {
if (elt->op == OP_NONE)
continue;
n_preds++;
if (!ops[op]) {
parse_error(pe, FILT_ERR_INVALID_OP, pos + i);
goto err_free;
}
return n_preds;
}
i += strlen(ops[op]);
struct check_pred_data {
int count;
int max;
};
while (isspace(str[i]))
i++;
static int check_pred_tree_cb(enum move_type move, struct filter_pred *pred,
int *err, void *data)
{
struct check_pred_data *d = data;
s = i;
if (WARN_ON(d->count++ > d->max)) {
*err = -EINVAL;
return WALK_PRED_ABORT;
}
return WALK_PRED_DEFAULT;
}
pred = kzalloc(sizeof(*pred), GFP_KERNEL);
if (!pred)
return -ENOMEM;
/*
* 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 = {
pred->field = field;
pred->offset = field->offset;
pred->op = op;
if (ftrace_event_is_function(call)) {
/*
* 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.
* Perf does things different with function events.
* It only allows an "ip" field, and expects a string.
* But the string does not need to be surrounded by quotes.
* If it is a string, the assigned function as a nop,
* (perf doesn't use it) and grab everything.
*/
.max = 3 * filter->n_preds,
.count = 0,
};
if (strcmp(field->name, "ip") != 0) {
parse_error(pe, FILT_ERR_IP_FIELD_ONLY, pos + i);
goto err_free;
}
pred->fn = filter_pred_none;
/*
* Quotes are not required, but if they exist then we need
* to read them till we hit a matching one.
*/
if (str[i] == '\'' || str[i] == '"')
q = str[i];
else
q = 0;
for (i++; str[i]; i++) {
if (q && str[i] == q)
break;
if (!q && (str[i] == ')' || str[i] == '&' ||
str[i] == '|'))
break;
}
/* Skip quotes */
if (q)
s++;
len = i - s;
if (len >= MAX_FILTER_STR_VAL) {
parse_error(pe, FILT_ERR_OPERAND_TOO_LONG, pos + i);
goto err_free;
}
return walk_pred_tree(filter->preds, root,
check_pred_tree_cb, &data);
}
pred->regex.len = len;
strncpy(pred->regex.pattern, str + s, len);
pred->regex.pattern[len] = 0;
/* This is either a string, or an integer */
} else if (str[i] == '\'' || str[i] == '"') {
char q = str[i];
/* Make sure the op is OK for strings */
switch (op) {
case OP_NE:
pred->not = 1;
/* Fall through */
case OP_GLOB:
case OP_EQ:
break;
default:
parse_error(pe, FILT_ERR_ILLEGAL_FIELD_OP, pos + i);
goto err_free;
}
static int count_leafs_cb(enum move_type move, struct filter_pred *pred,
int *err, void *data)
{
int *count = data;
/* Make sure the field is OK for strings */
if (!is_string_field(field)) {
parse_error(pe, FILT_ERR_EXPECT_DIGIT, pos + i);
goto err_free;
}
if ((move == MOVE_DOWN) &&
(pred->left == FILTER_PRED_INVALID))
(*count)++;
for (i++; str[i]; i++) {
if (str[i] == q)
break;
}
if (!str[i]) {
parse_error(pe, FILT_ERR_MISSING_QUOTE, pos + i);
goto err_free;
}
return WALK_PRED_DEFAULT;
}
/* Skip quotes */
s++;
len = i - s;
if (len >= MAX_FILTER_STR_VAL) {
parse_error(pe, FILT_ERR_OPERAND_TOO_LONG, pos + i);
goto err_free;
}
static int count_leafs(struct filter_pred *preds, struct filter_pred *root)
{
int count = 0, ret;
pred->regex.len = len;
strncpy(pred->regex.pattern, str + s, len);
pred->regex.pattern[len] = 0;
ret = walk_pred_tree(preds, root, count_leafs_cb, &count);
WARN_ON(ret);
return count;
}
filter_build_regex(pred);
struct fold_pred_data {
struct filter_pred *root;
int count;
int children;
};
if (field->filter_type == FILTER_COMM) {
pred->fn = filter_pred_comm;
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;
} else if (field->filter_type == FILTER_STATIC_STRING) {
pred->fn = filter_pred_string;
pred->regex.field_len = field->size;
if (move != MOVE_DOWN)
return WALK_PRED_DEFAULT;
if (pred->left != FILTER_PRED_INVALID)
return WALK_PRED_DEFAULT;
} else if (field->filter_type == FILTER_DYN_STRING)
pred->fn = filter_pred_strloc;
else
pred->fn = filter_pred_pchar;
/* go past the last quote */
i++;
if (WARN_ON(d->count == d->children)) {
*err = -EINVAL;
return WALK_PRED_ABORT;
}
} else if (isdigit(str[i])) {
pred->index &= ~FILTER_PRED_FOLD;
root->ops[d->count++] = pred->index;
return WALK_PRED_DEFAULT;
}
/* Make sure the field is not a string */
if (is_string_field(field)) {
parse_error(pe, FILT_ERR_EXPECT_STRING, pos + i);
goto err_free;
}
static int fold_pred(struct filter_pred *preds, struct filter_pred *root)
{
struct fold_pred_data data = {
.root = root,
.count = 0,
};
int children;
if (op == OP_GLOB) {
parse_error(pe, FILT_ERR_ILLEGAL_FIELD_OP, pos + i);
goto err_free;
}
/* No need to keep the fold flag */
root->index &= ~FILTER_PRED_FOLD;
/* We allow 0xDEADBEEF */
while (isalnum(str[i]))
i++;
/* If the root is a leaf then do nothing */
if (root->left == FILTER_PRED_INVALID)
return 0;
len = i - s;
/* 0xfeedfacedeadbeef is 18 chars max */
if (len >= sizeof(num_buf)) {
parse_error(pe, FILT_ERR_OPERAND_TOO_LONG, pos + i);
goto err_free;
}
/* count the children */
children = count_leafs(preds, &preds[root->left]);
children += count_leafs(preds, &preds[root->right]);
strncpy(num_buf, str + s, len);
num_buf[len] = 0;
root->ops = kcalloc(children, sizeof(*root->ops), GFP_KERNEL);
if (!root->ops)
return -ENOMEM;
/* Make sure it is a value */
if (field->is_signed)
ret = kstrtoll(num_buf, 0, &val);
else
ret = kstrtoull(num_buf, 0, &val);
if (ret) {
parse_error(pe, FILT_ERR_ILLEGAL_INTVAL, pos + s);
goto err_free;
}
root->val = children;
data.children = children;
return walk_pred_tree(preds, root, fold_pred_cb, &data);
}
pred->val = val;
static int fold_pred_tree_cb(enum move_type move, struct filter_pred *pred,
int *err, void *data)
{
struct filter_pred *preds = data;
if (field->filter_type == FILTER_CPU)
pred->fn = filter_pred_cpu;
else {
pred->fn = select_comparison_fn(pred->op, field->size,
field->is_signed);
if (pred->op == OP_NE)
pred->not = 1;
}
if (move != MOVE_DOWN)
return WALK_PRED_DEFAULT;
if (!(pred->index & FILTER_PRED_FOLD))
return WALK_PRED_DEFAULT;
} else {
parse_error(pe, FILT_ERR_INVALID_VALUE, pos + i);
goto err_free;
}
*err = fold_pred(preds, pred);
if (*err)
return WALK_PRED_ABORT;
*pred_ptr = pred;
return i;
/* eveyrhing below is folded, continue with parent */
return WALK_PRED_PARENT;
err_free:
kfree(pred);
return -EINVAL;
}
enum {
TOO_MANY_CLOSE = -1,
TOO_MANY_OPEN = -2,
MISSING_QUOTE = -3,
};
/*
* 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.
* Read the filter string once to calculate the number of predicates
* as well as how deep the parentheses go.
*
* Returns:
* 0 - everything is fine (err is undefined)
* -1 - too many ')'
* -2 - too many '('
* -3 - No matching quote
*/
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;
static int calc_stack(const char *str, int *parens, int *preds, int *err)
{
bool is_pred = false;
int nr_preds = 0;
int open = 1; /* Count the expression as "(E)" */
int last_quote = 0;
int max_open = 1;
int quote = 0;
int i;
if (!dry_run) {
err = __alloc_pred_stack(&stack, n_preds);
if (err)
return err;
err = __alloc_preds(filter, n_preds);
if (err)
goto fail;
}
*err = 0;
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;
}
for (i = 0; str[i]; i++) {
if (isspace(str[i]))
continue;
if (quote) {
if (str[i] == quote)
quote = 0;
continue;
}
if (elt->op == OP_NOT) {
if (!n_preds || operand1 || operand2) {
parse_error(ps, FILT_ERR_ILLEGAL_NOT_OP, 0);
err = -EINVAL;
goto fail;
switch (str[i]) {
case '\'':
case '"':
quote = str[i];
last_quote = i;
break;
case '|':
case '&':
if (str[i+1] != str[i])
break;
is_pred = false;
continue;
case '(':
is_pred = false;
open++;
if (open > max_open)
max_open = open;
continue;
case ')':
is_pred = false;
if (open == 1) {
*err = i;
return TOO_MANY_CLOSE;
}
if (!dry_run)
filter->preds[n_preds - 1].not ^= 1;
open--;
continue;
}
if (WARN_ON(n_preds++ == MAX_FILTER_PRED)) {
parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
err = -ENOSPC;
goto fail;
if (!is_pred) {
nr_preds++;
is_pred = true;
}
}
pred = create_pred(ps, call, elt->op, operand1, operand2);
if (!pred) {
err = -EINVAL;
goto fail;
}
if (quote) {
*err = last_quote;
return MISSING_QUOTE;
}
if (!dry_run) {
err = filter_add_pred(ps, filter, pred, &stack);
if (err)
goto fail;
}
if (open != 1) {
int level = open;
operand1 = operand2 = NULL;
/* find the bad open */
for (i--; i; i--) {
if (quote) {
if (str[i] == quote)
quote = 0;
continue;
}
switch (str[i]) {
case '(':
if (level == open) {
*err = i;
return TOO_MANY_OPEN;
}
level--;
break;
case ')':
level++;
break;
case '\'':
case '"':
quote = str[i];
break;
}
}
/* First character is the '(' with missing ')' */
*err = 0;
return TOO_MANY_OPEN;
}
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;
/* Set the size of the required stacks */
*parens = max_open;
*preds = nr_preds;
return 0;
}
static int process_preds(struct trace_event_call *call,
const char *filter_string,
struct event_filter *filter,
struct filter_parse_error *pe)
{
struct prog_entry *prog;
int nr_parens;
int nr_preds;
int index;
int ret;
ret = calc_stack(filter_string, &nr_parens, &nr_preds, &index);
if (ret < 0) {
switch (ret) {
case MISSING_QUOTE:
parse_error(pe, FILT_ERR_MISSING_QUOTE, index);
break;
case TOO_MANY_OPEN:
parse_error(pe, FILT_ERR_TOO_MANY_OPEN, index);
break;
default:
parse_error(pe, FILT_ERR_TOO_MANY_CLOSE, index);
}
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;
return ret;
}
err = 0;
fail:
__free_pred_stack(&stack);
return err;
if (!nr_preds) {
prog = NULL;
} else {
prog = predicate_parse(filter_string, nr_parens, nr_preds,
parse_pred, call, pe);
if (IS_ERR(prog))
return PTR_ERR(prog);
}
rcu_assign_pointer(filter->prog, prog);
return 0;
}
static inline void event_set_filtered_flag(struct trace_event_file *file)
......@@ -1753,9 +1558,9 @@ struct filter_list {
struct event_filter *filter;
};
static int replace_system_preds(struct trace_subsystem_dir *dir,
static int process_system_preds(struct trace_subsystem_dir *dir,
struct trace_array *tr,
struct filter_parse_state *ps,
struct filter_parse_error *pe,
char *filter_string)
{
struct trace_event_file *file;
......@@ -1766,29 +1571,11 @@ static int replace_system_preds(struct trace_subsystem_dir *dir,
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) {
if (file->system != dir)
continue;
if (event_no_set_filter_flag(file))
continue;
filter = kzalloc(sizeof(*filter), GFP_KERNEL);
if (!filter)
goto fail_mem;
......@@ -1797,11 +1584,11 @@ static int replace_system_preds(struct trace_subsystem_dir *dir,
if (!filter->filter_string)
goto fail_mem;
err = replace_preds(file->event_call, filter, ps, false);
err = process_preds(file->event_call, filter_string, filter, pe);
if (err) {
filter_disable(file);
parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
append_filter_err(ps, filter);
parse_error(pe, FILT_ERR_BAD_SUBSYS_FILTER, 0);
append_filter_err(pe, filter);
} else
event_set_filtered_flag(file);
......@@ -1843,7 +1630,7 @@ static int replace_system_preds(struct trace_subsystem_dir *dir,
list_del(&filter_item->list);
kfree(filter_item);
}
parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
parse_error(pe, FILT_ERR_BAD_SUBSYS_FILTER, 0);
return -EINVAL;
fail_mem:
kfree(filter);
......@@ -1859,16 +1646,16 @@ static int replace_system_preds(struct trace_subsystem_dir *dir,
}
static int create_filter_start(char *filter_string, bool set_str,
struct filter_parse_state **psp,
struct filter_parse_error **pse,
struct event_filter **filterp)
{
struct event_filter *filter;
struct filter_parse_state *ps = NULL;
struct filter_parse_error *pe = NULL;
int err = 0;
WARN_ON_ONCE(*psp || *filterp);
if (WARN_ON_ONCE(*pse || *filterp))
return -EINVAL;
/* allocate everything, and if any fails, free all and fail */
filter = kzalloc(sizeof(*filter), GFP_KERNEL);
if (filter && set_str) {
filter->filter_string = kstrdup(filter_string, GFP_KERNEL);
......@@ -1876,32 +1663,24 @@ static int create_filter_start(char *filter_string, bool set_str,
err = -ENOMEM;
}
ps = kzalloc(sizeof(*ps), GFP_KERNEL);
pe = kzalloc(sizeof(*pe), GFP_KERNEL);
if (!filter || !ps || err) {
kfree(ps);
if (!filter || !pe || err) {
kfree(pe);
__free_filter(filter);
return -ENOMEM;
}
/* we're committed to creating a new filter */
*filterp = filter;
*psp = ps;
*pse = pe;
parse_init(ps, filter_ops, filter_string);
err = filter_parse(ps);
if (err && set_str)
append_filter_err(ps, filter);
return err;
return 0;
}
static void create_filter_finish(struct filter_parse_state *ps)
static void create_filter_finish(struct filter_parse_error *pe)
{
if (ps) {
filter_opstack_clear(ps);
postfix_clear(ps);
kfree(ps);
}
kfree(pe);
}
/**
......@@ -1921,24 +1700,20 @@ static void create_filter_finish(struct filter_parse_state *ps)
* freeing it.
*/
static int create_filter(struct trace_event_call *call,
char *filter_str, bool set_str,
char *filter_string, bool set_str,
struct event_filter **filterp)
{
struct filter_parse_error *pe = NULL;
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);
err = create_filter_start(filter_string, set_str, &pe, &filter);
if (err)
return err;
err = process_preds(call, filter_string, filter, pe);
if (err && set_str)
append_filter_err(pe, filter);
*filterp = filter;
return err;
......@@ -1965,21 +1740,21 @@ static int create_system_filter(struct trace_subsystem_dir *dir,
char *filter_str, struct event_filter **filterp)
{
struct event_filter *filter = NULL;
struct filter_parse_state *ps = NULL;
struct filter_parse_error *pe = NULL;
int err;
err = create_filter_start(filter_str, true, &ps, &filter);
err = create_filter_start(filter_str, true, &pe, &filter);
if (!err) {
err = replace_system_preds(dir, tr, ps, filter_str);
err = process_system_preds(dir, tr, pe, 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);
append_filter_err(pe, filter);
}
}
create_filter_finish(ps);
create_filter_finish(pe);
*filterp = filter;
return err;
......@@ -2162,66 +1937,79 @@ static int __ftrace_function_set_filter(int filter, char *buf, int len,
return ret;
}
static int ftrace_function_check_pred(struct filter_pred *pred, int leaf)
static int ftrace_function_check_pred(struct filter_pred *pred)
{
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;
/*
* Check the 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;
}
if (strcmp(field->name, "ip"))
return -EINVAL;
return 0;
}
static int ftrace_function_set_filter_cb(enum move_type move,
struct filter_pred *pred,
int *err, void *data)
static int ftrace_function_set_filter_pred(struct filter_pred *pred,
struct function_filter_data *data)
{
int ret;
/* 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);
}
ret = ftrace_function_check_pred(pred);
if (ret)
return ret;
return __ftrace_function_set_filter(pred->op == OP_EQ,
pred->regex.pattern,
pred->regex.len,
data);
}
static bool is_or(struct prog_entry *prog, int i)
{
int target;
return (*err) ? WALK_PRED_ABORT : WALK_PRED_DEFAULT;
/*
* Only "||" is allowed for function events, thus,
* all true branches should jump to true, and any
* false branch should jump to false.
*/
target = prog[i].target + 1;
/* True and false have NULL preds (all prog entries should jump to one */
if (prog[target].pred)
return false;
/* prog[target].target is 1 for TRUE, 0 for FALSE */
return prog[i].when_to_branch == prog[target].target;
}
static int ftrace_function_set_filter(struct perf_event *event,
struct event_filter *filter)
{
struct prog_entry *prog = filter->prog;
struct function_filter_data data = {
.first_filter = 1,
.first_notrace = 1,
.ops = &event->ftrace_ops,
};
int i;
for (i = 0; prog[i].pred; i++) {
struct filter_pred *pred = prog[i].pred;
if (!is_or(prog, i))
return -EINVAL;
return walk_pred_tree(filter->preds, filter->root,
ftrace_function_set_filter_cb, &data);
if (ftrace_function_set_filter_pred(pred, &data) < 0)
return -EINVAL;
}
return 0;
}
#else
static int ftrace_function_set_filter(struct perf_event *event,
......@@ -2364,26 +2152,27 @@ static int test_pred_visited_fn(struct filter_pred *pred, void *event)
return 1;
}
static int test_walk_pred_cb(enum move_type move, struct filter_pred *pred,
int *err, void *data)
static void update_pred_fn(struct event_filter *filter, char *fields)
{
char *fields = data;
struct prog_entry *prog = filter->prog;
int i;
if ((move == MOVE_DOWN) &&
(pred->left == FILTER_PRED_INVALID)) {
for (i = 0; prog[i].pred; i++) {
struct filter_pred *pred = prog[i].pred;
struct ftrace_event_field *field = pred->field;
WARN_ON_ONCE(!pred->fn);
if (!field) {
WARN(1, "all leafs should have field defined");
return WALK_PRED_DEFAULT;
WARN_ONCE(1, "all leafs should have field defined %d", i);
continue;
}
if (!strchr(fields, *field->name))
return WALK_PRED_DEFAULT;
continue;
WARN_ON(!pred->fn);
pred->fn = test_pred_visited_fn;
}
return WALK_PRED_DEFAULT;
}
static __init int ftrace_test_event_filter(void)
......@@ -2413,9 +2202,7 @@ static __init int ftrace_test_event_filter(void)
*/
preempt_disable();
if (*d->not_visited)
walk_pred_tree(filter->preds, filter->root,
test_walk_pred_cb,
d->not_visited);
update_pred_fn(filter, d->not_visited);
test_pred_visited = 0;
err = filter_match_preds(filter, &d->rec);
......
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