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lockdep: simplify check_prev_add_irq()

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Remove the manual state iteration thingy.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2009-01-22 18:10:42 +01:00 committed by Ingo Molnar
parent f510b233cf
commit 4f367d8adc
1 changed files with 62 additions and 94 deletions
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156
kernel/lockdep.c
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@ -1268,9 +1268,49 @@ check_usage(struct task_struct *curr, struct held_lock *prev,
bit_backwards, bit_forwards, irqclass);
}
static int
check_prev_add_irq(struct task_struct *curr, struct held_lock *prev,
struct held_lock *next)
static const char *state_names[] = {
#define LOCKDEP_STATE(__STATE) \
STR(__STATE),
#include "lockdep_states.h"
#undef LOCKDEP_STATE
};
static const char *state_rnames[] = {
#define LOCKDEP_STATE(__STATE) \
STR(__STATE)"-READ",
#include "lockdep_states.h"
#undef LOCKDEP_STATE
};
static inline const char *state_name(enum lock_usage_bit bit)
{
return (bit & 1) ? state_rnames[bit >> 2] : state_names[bit >> 2];
}
static int exclusive_bit(int new_bit)
{
/*
* USED_IN
* USED_IN_READ
* ENABLED
* ENABLED_READ
*
* bit 0 - write/read
* bit 1 - used_in/enabled
* bit 2+ state
*/
int state = new_bit & ~3;
int dir = new_bit & 2;
/*
* keep state, bit flip the direction and strip read.
*/
return state | (dir ^ 2);
}
static int check_irq_usage(struct task_struct *curr, struct held_lock *prev,
struct held_lock *next, enum lock_usage_bit bit)
{
/*
* Prove that the new dependency does not connect a hardirq-safe
@ -1278,58 +1318,34 @@ check_prev_add_irq(struct task_struct *curr, struct held_lock *prev,
* the backwards-subgraph starting at <prev>, and the
* forwards-subgraph starting at <next>:
*/
if (!check_usage(curr, prev, next, LOCK_USED_IN_HARDIRQ,
LOCK_ENABLED_HARDIRQ, "hard"))
if (!check_usage(curr, prev, next, bit,
exclusive_bit(bit), state_name(bit)))
return 0;
bit++; /* _READ */
/*
* Prove that the new dependency does not connect a hardirq-safe-read
* lock with a hardirq-unsafe lock - to achieve this we search
* the backwards-subgraph starting at <prev>, and the
* forwards-subgraph starting at <next>:
*/
if (!check_usage(curr, prev, next, LOCK_USED_IN_HARDIRQ_READ,
LOCK_ENABLED_HARDIRQ, "hard-read"))
if (!check_usage(curr, prev, next, bit,
exclusive_bit(bit), state_name(bit)))
return 0;
/*
* Prove that the new dependency does not connect a softirq-safe
* lock with a softirq-unsafe lock - to achieve this we search
* the backwards-subgraph starting at <prev>, and the
* forwards-subgraph starting at <next>:
*/
if (!check_usage(curr, prev, next, LOCK_USED_IN_SOFTIRQ,
LOCK_ENABLED_SOFTIRQ, "soft"))
return 0;
/*
* Prove that the new dependency does not connect a softirq-safe-read
* lock with a softirq-unsafe lock - to achieve this we search
* the backwards-subgraph starting at <prev>, and the
* forwards-subgraph starting at <next>:
*/
if (!check_usage(curr, prev, next, LOCK_USED_IN_SOFTIRQ_READ,
LOCK_ENABLED_SOFTIRQ, "soft"))
return 0;
return 1;
}
/*
* Prove that the new dependency does not connect a reclaim-fs-safe
* lock with a reclaim-fs-unsafe lock - to achieve this we search
* the backwards-subgraph starting at <prev>, and the
* forwards-subgraph starting at <next>:
*/
if (!check_usage(curr, prev, next, LOCK_USED_IN_RECLAIM_FS,
LOCK_ENABLED_RECLAIM_FS, "reclaim-fs"))
return 0;
/*
* Prove that the new dependency does not connect a reclaim-fs-safe-read
* lock with a reclaim-fs-unsafe lock - to achieve this we search
* the backwards-subgraph starting at <prev>, and the
* forwards-subgraph starting at <next>:
*/
if (!check_usage(curr, prev, next, LOCK_USED_IN_RECLAIM_FS_READ,
LOCK_ENABLED_RECLAIM_FS, "reclaim-fs-read"))
static int
check_prev_add_irq(struct task_struct *curr, struct held_lock *prev,
struct held_lock *next)
{
#define LOCKDEP_STATE(__STATE) \
if (!check_irq_usage(curr, prev, next, LOCK_USED_IN_##__STATE)) \
return 0;
#include "lockdep_states.h"
#undef LOCKDEP_STATE
return 1;
}
@ -1984,30 +2000,6 @@ static int RECLAIM_FS_verbose(struct lock_class *class)
#define STRICT_READ_CHECKS 1
static const char *state_names[] = {
#define LOCKDEP_STATE(__STATE) \
STR(__STATE),
#include "lockdep_states.h"
#undef LOCKDEP_STATE
};
static inline const char *state_name(enum lock_usage_bit bit)
{
return state_names[bit >> 2];
}
static const char *state_rnames[] = {
#define LOCKDEP_STATE(__STATE) \
STR(__STATE)"-READ",
#include "lockdep_states.h"
#undef LOCKDEP_STATE
};
static inline const char *state_rname(enum lock_usage_bit bit)
{
return state_rnames[bit >> 2];
}
static int (*state_verbose_f[])(struct lock_class *class) = {
#define LOCKDEP_STATE(__STATE) \
__STATE##_verbose,
@ -2021,37 +2013,12 @@ static inline int state_verbose(enum lock_usage_bit bit,
return state_verbose_f[bit >> 2](class);
}
static int exclusive_bit(int new_bit)
{
/*
* USED_IN
* USED_IN_READ
* ENABLED
* ENABLED_READ
*
* bit 0 - write/read
* bit 1 - used_in/enabled
* bit 2+ state
*/
int state = new_bit & ~3;
int dir = new_bit & 2;
/*
* keep state, bit flip the direction and strip read.
*/
return state | (dir ^ 2);
}
typedef int (*check_usage_f)(struct task_struct *, struct held_lock *,
enum lock_usage_bit bit, const char *name);
static int
mark_lock_irq(struct task_struct *curr, struct held_lock *this, int new_bit)
{
const char *name = state_name(new_bit);
const char *rname = state_rname(new_bit);
int excl_bit = exclusive_bit(new_bit);
int read = new_bit & 1;
int dir = new_bit & 2;
@ -2078,7 +2045,7 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, int new_bit)
* states.
*/
if ((!read || !dir || STRICT_READ_CHECKS) &&
!usage(curr, this, excl_bit, name))
!usage(curr, this, excl_bit, state_name(new_bit)))
return 0;
/*
@ -2089,7 +2056,8 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, int new_bit)
return 0;
if (STRICT_READ_CHECKS &&
!usage(curr, this, excl_bit + 1, rname))
!usage(curr, this, excl_bit + 1,
state_name(new_bit + 1)))
return 0;
}