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perf/kprobes updates:

Browse source 
- Make kretprobes lockless to avoid the rp->lock performance and potential
    lock ordering issues.
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Merge tag 'perf-kprobes-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf/kprobes updates from Thomas Gleixner:
 "Make kretprobes lockless to avoid the rp->lock performance and
  potential lock ordering issues"

* tag 'perf-kprobes-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/atomics: Regenerate the atomics-check SHA1's
  kprobes: Replace rp->free_instance with freelist
  freelist: Implement lockless freelist
  asm-generic/atomic: Add try_cmpxchg() fallbacks
  kprobes: Remove kretprobe hash
  llist: Add nonatomic __llist_add() and __llist_dell_all()
This commit is contained in:
Linus Torvalds 2020-12-14 17:41:38 -08:00
commit 76d4acf22b
16 changed files with 649 additions and 353 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

2
arch/x86/include/asm/atomic.h
View file

@ -199,7 +199,7 @@ static __always_inline int arch_atomic_cmpxchg(atomic_t *v, int old, int new)
static __always_inline bool arch_atomic_try_cmpxchg(atomic_t *v, int *old, int new)
{
return try_cmpxchg(&v->counter, old, new);
return arch_try_cmpxchg(&v->counter, old, new);
}
#define arch_atomic_try_cmpxchg arch_atomic_try_cmpxchg

2
arch/x86/include/asm/atomic64_64.h
View file

@ -187,7 +187,7 @@ static inline s64 arch_atomic64_cmpxchg(atomic64_t *v, s64 old, s64 new)
static __always_inline bool arch_atomic64_try_cmpxchg(atomic64_t *v, s64 *old, s64 new)
{
return try_cmpxchg(&v->counter, old, new);
return arch_try_cmpxchg(&v->counter, old, new);
}
#define arch_atomic64_try_cmpxchg arch_atomic64_try_cmpxchg

2
arch/x86/include/asm/cmpxchg.h
View file

@ -221,7 +221,7 @@ extern void __add_wrong_size(void)
#define __try_cmpxchg(ptr, pold, new, size) \
__raw_try_cmpxchg((ptr), (pold), (new), (size), LOCK_PREFIX)
#define try_cmpxchg(ptr, pold, new) \
#define arch_try_cmpxchg(ptr, pold, new) \
__try_cmpxchg((ptr), (pold), (new), sizeof(*(ptr)))
/*

216
include/asm-generic/atomic-instrumented.h
View file

@ -1642,148 +1642,192 @@ atomic64_dec_if_positive(atomic64_t *v)
#endif
#if !defined(arch_xchg_relaxed) || defined(arch_xchg)
#define xchg(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_xchg(__ai_ptr, __VA_ARGS__); \
#define xchg(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_xchg(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_xchg_acquire)
#define xchg_acquire(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_xchg_acquire(__ai_ptr, __VA_ARGS__); \
#define xchg_acquire(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_xchg_acquire(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_xchg_release)
#define xchg_release(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_xchg_release(__ai_ptr, __VA_ARGS__); \
#define xchg_release(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_xchg_release(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_xchg_relaxed)
#define xchg_relaxed(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_xchg_relaxed(__ai_ptr, __VA_ARGS__); \
#define xchg_relaxed(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_xchg_relaxed(__ai_ptr, __VA_ARGS__); \
})
#endif
#if !defined(arch_cmpxchg_relaxed) || defined(arch_cmpxchg)
#define cmpxchg(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg(__ai_ptr, __VA_ARGS__); \
#define cmpxchg(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_cmpxchg_acquire)
#define cmpxchg_acquire(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg_acquire(__ai_ptr, __VA_ARGS__); \
#define cmpxchg_acquire(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg_acquire(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_cmpxchg_release)
#define cmpxchg_release(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg_release(__ai_ptr, __VA_ARGS__); \
#define cmpxchg_release(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg_release(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_cmpxchg_relaxed)
#define cmpxchg_relaxed(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg_relaxed(__ai_ptr, __VA_ARGS__); \
#define cmpxchg_relaxed(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg_relaxed(__ai_ptr, __VA_ARGS__); \
})
#endif
#if !defined(arch_cmpxchg64_relaxed) || defined(arch_cmpxchg64)
#define cmpxchg64(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64(__ai_ptr, __VA_ARGS__); \
#define cmpxchg64(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_cmpxchg64_acquire)
#define cmpxchg64_acquire(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64_acquire(__ai_ptr, __VA_ARGS__); \
#define cmpxchg64_acquire(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64_acquire(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_cmpxchg64_release)
#define cmpxchg64_release(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64_release(__ai_ptr, __VA_ARGS__); \
#define cmpxchg64_release(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64_release(__ai_ptr, __VA_ARGS__); \
})
#endif
#if defined(arch_cmpxchg64_relaxed)
#define cmpxchg64_relaxed(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64_relaxed(__ai_ptr, __VA_ARGS__); \
#define cmpxchg64_relaxed(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64_relaxed(__ai_ptr, __VA_ARGS__); \
})
#endif
#define cmpxchg_local(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg_local(__ai_ptr, __VA_ARGS__); \
#if !defined(arch_try_cmpxchg_relaxed) || defined(arch_try_cmpxchg)
#define try_cmpxchg(ptr, oldp, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
typeof(oldp) __ai_oldp = (oldp); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
arch_try_cmpxchg(__ai_ptr, __ai_oldp, __VA_ARGS__); \
})
#endif
#if defined(arch_try_cmpxchg_acquire)
#define try_cmpxchg_acquire(ptr, oldp, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
typeof(oldp) __ai_oldp = (oldp); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
arch_try_cmpxchg_acquire(__ai_ptr, __ai_oldp, __VA_ARGS__); \
})
#endif
#if defined(arch_try_cmpxchg_release)
#define try_cmpxchg_release(ptr, oldp, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
typeof(oldp) __ai_oldp = (oldp); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
arch_try_cmpxchg_release(__ai_ptr, __ai_oldp, __VA_ARGS__); \
})
#endif
#if defined(arch_try_cmpxchg_relaxed)
#define try_cmpxchg_relaxed(ptr, oldp, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
typeof(oldp) __ai_oldp = (oldp); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
arch_try_cmpxchg_relaxed(__ai_ptr, __ai_oldp, __VA_ARGS__); \
})
#endif
#define cmpxchg_local(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg_local(__ai_ptr, __VA_ARGS__); \
})
#define cmpxchg64_local(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64_local(__ai_ptr, __VA_ARGS__); \
#define cmpxchg64_local(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_cmpxchg64_local(__ai_ptr, __VA_ARGS__); \
})
#define sync_cmpxchg(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_sync_cmpxchg(__ai_ptr, __VA_ARGS__); \
#define sync_cmpxchg(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
arch_sync_cmpxchg(__ai_ptr, __VA_ARGS__); \
})
#define cmpxchg_double(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, 2 * sizeof(*__ai_ptr)); \
arch_cmpxchg_double(__ai_ptr, __VA_ARGS__); \
#define cmpxchg_double(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, 2 * sizeof(*__ai_ptr)); \
arch_cmpxchg_double(__ai_ptr, __VA_ARGS__); \
})
#define cmpxchg_double_local(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, 2 * sizeof(*__ai_ptr)); \
arch_cmpxchg_double_local(__ai_ptr, __VA_ARGS__); \
#define cmpxchg_double_local(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
instrument_atomic_write(__ai_ptr, 2 * sizeof(*__ai_ptr)); \
arch_cmpxchg_double_local(__ai_ptr, __VA_ARGS__); \
})
#endif /* _ASM_GENERIC_ATOMIC_INSTRUMENTED_H */
// 9d5e6a315fb1335d02f0ccd3655a91c3dafcc63e
// 4bec382e44520f4d8267e42620054db26a659ea3

90
include/linux/atomic-arch-fallback.h
View file

@ -9,9 +9,9 @@
#include <linux/compiler.h>
#ifndef arch_xchg_relaxed
#define arch_xchg_relaxed arch_xchg
#define arch_xchg_acquire arch_xchg
#define arch_xchg_release arch_xchg
#define arch_xchg_acquire arch_xchg
#define arch_xchg_release arch_xchg
#define arch_xchg_relaxed arch_xchg
#else /* arch_xchg_relaxed */
#ifndef arch_xchg_acquire
@ -32,9 +32,9 @@
#endif /* arch_xchg_relaxed */
#ifndef arch_cmpxchg_relaxed
#define arch_cmpxchg_relaxed arch_cmpxchg
#define arch_cmpxchg_acquire arch_cmpxchg
#define arch_cmpxchg_release arch_cmpxchg
#define arch_cmpxchg_acquire arch_cmpxchg
#define arch_cmpxchg_release arch_cmpxchg
#define arch_cmpxchg_relaxed arch_cmpxchg
#else /* arch_cmpxchg_relaxed */
#ifndef arch_cmpxchg_acquire
@ -55,9 +55,9 @@
#endif /* arch_cmpxchg_relaxed */
#ifndef arch_cmpxchg64_relaxed
#define arch_cmpxchg64_relaxed arch_cmpxchg64
#define arch_cmpxchg64_acquire arch_cmpxchg64
#define arch_cmpxchg64_release arch_cmpxchg64
#define arch_cmpxchg64_acquire arch_cmpxchg64
#define arch_cmpxchg64_release arch_cmpxchg64
#define arch_cmpxchg64_relaxed arch_cmpxchg64
#else /* arch_cmpxchg64_relaxed */
#ifndef arch_cmpxchg64_acquire
@ -77,6 +77,76 @@
#endif /* arch_cmpxchg64_relaxed */
#ifndef arch_try_cmpxchg_relaxed
#ifdef arch_try_cmpxchg
#define arch_try_cmpxchg_acquire arch_try_cmpxchg
#define arch_try_cmpxchg_release arch_try_cmpxchg
#define arch_try_cmpxchg_relaxed arch_try_cmpxchg
#endif /* arch_try_cmpxchg */
#ifndef arch_try_cmpxchg
#define arch_try_cmpxchg(_ptr, _oldp, _new) \
({ \
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \
___r = arch_cmpxchg((_ptr), ___o, (_new)); \
if (unlikely(___r != ___o)) \
*___op = ___r; \
likely(___r == ___o); \
})
#endif /* arch_try_cmpxchg */
#ifndef arch_try_cmpxchg_acquire
#define arch_try_cmpxchg_acquire(_ptr, _oldp, _new) \
({ \
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \
___r = arch_cmpxchg_acquire((_ptr), ___o, (_new)); \
if (unlikely(___r != ___o)) \
*___op = ___r; \
likely(___r == ___o); \
})
#endif /* arch_try_cmpxchg_acquire */
#ifndef arch_try_cmpxchg_release
#define arch_try_cmpxchg_release(_ptr, _oldp, _new) \
({ \
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \
___r = arch_cmpxchg_release((_ptr), ___o, (_new)); \
if (unlikely(___r != ___o)) \
*___op = ___r; \
likely(___r == ___o); \
})
#endif /* arch_try_cmpxchg_release */
#ifndef arch_try_cmpxchg_relaxed
#define arch_try_cmpxchg_relaxed(_ptr, _oldp, _new) \
({ \
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \
___r = arch_cmpxchg_relaxed((_ptr), ___o, (_new)); \
if (unlikely(___r != ___o)) \
*___op = ___r; \
likely(___r == ___o); \
})
#endif /* arch_try_cmpxchg_relaxed */
#else /* arch_try_cmpxchg_relaxed */
#ifndef arch_try_cmpxchg_acquire
#define arch_try_cmpxchg_acquire(...) \
__atomic_op_acquire(arch_try_cmpxchg, __VA_ARGS__)
#endif
#ifndef arch_try_cmpxchg_release
#define arch_try_cmpxchg_release(...) \
__atomic_op_release(arch_try_cmpxchg, __VA_ARGS__)
#endif
#ifndef arch_try_cmpxchg
#define arch_try_cmpxchg(...) \
__atomic_op_fence(arch_try_cmpxchg, __VA_ARGS__)
#endif
#endif /* arch_try_cmpxchg_relaxed */
#ifndef arch_atomic_read_acquire
static __always_inline int
arch_atomic_read_acquire(const atomic_t *v)
@ -2288,4 +2358,4 @@ arch_atomic64_dec_if_positive(atomic64_t *v)
#endif
#endif /* _LINUX_ATOMIC_FALLBACK_H */
// 90cd26cfd69d2250303d654955a0cc12620fb91b
// cca554917d7ea73d5e3e7397dd70c484cad9b2c4

90
include/linux/atomic-fallback.h
View file

@ -9,9 +9,9 @@
#include <linux/compiler.h>
#ifndef xchg_relaxed
#define xchg_relaxed xchg
#define xchg_acquire xchg
#define xchg_release xchg
#define xchg_acquire xchg
#define xchg_release xchg
#define xchg_relaxed xchg
#else /* xchg_relaxed */
#ifndef xchg_acquire
@ -32,9 +32,9 @@
#endif /* xchg_relaxed */
#ifndef cmpxchg_relaxed
#define cmpxchg_relaxed cmpxchg
#define cmpxchg_acquire cmpxchg
#define cmpxchg_release cmpxchg
#define cmpxchg_acquire cmpxchg
#define cmpxchg_release cmpxchg
#define cmpxchg_relaxed cmpxchg
#else /* cmpxchg_relaxed */
#ifndef cmpxchg_acquire
@ -55,9 +55,9 @@
#endif /* cmpxchg_relaxed */
#ifndef cmpxchg64_relaxed
#define cmpxchg64_relaxed cmpxchg64
#define cmpxchg64_acquire cmpxchg64
#define cmpxchg64_release cmpxchg64
#define cmpxchg64_acquire cmpxchg64
#define cmpxchg64_release cmpxchg64
#define cmpxchg64_relaxed cmpxchg64
#else /* cmpxchg64_relaxed */
#ifndef cmpxchg64_acquire
@ -77,6 +77,76 @@
#endif /* cmpxchg64_relaxed */
#ifndef try_cmpxchg_relaxed
#ifdef try_cmpxchg
#define try_cmpxchg_acquire try_cmpxchg
#define try_cmpxchg_release try_cmpxchg
#define try_cmpxchg_relaxed try_cmpxchg
#endif /* try_cmpxchg */
#ifndef try_cmpxchg
#define try_cmpxchg(_ptr, _oldp, _new) \
({ \
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \
___r = cmpxchg((_ptr), ___o, (_new)); \
if (unlikely(___r != ___o)) \
*___op = ___r; \
likely(___r == ___o); \
})
#endif /* try_cmpxchg */
#ifndef try_cmpxchg_acquire
#define try_cmpxchg_acquire(_ptr, _oldp, _new) \
({ \
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \
___r = cmpxchg_acquire((_ptr), ___o, (_new)); \
if (unlikely(___r != ___o)) \
*___op = ___r; \
likely(___r == ___o); \
})
#endif /* try_cmpxchg_acquire */
#ifndef try_cmpxchg_release
#define try_cmpxchg_release(_ptr, _oldp, _new) \
({ \
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \
___r = cmpxchg_release((_ptr), ___o, (_new)); \
if (unlikely(___r != ___o)) \
*___op = ___r; \
likely(___r == ___o); \
})
#endif /* try_cmpxchg_release */
#ifndef try_cmpxchg_relaxed
#define try_cmpxchg_relaxed(_ptr, _oldp, _new) \
({ \
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \
___r = cmpxchg_relaxed((_ptr), ___o, (_new)); \
if (unlikely(___r != ___o)) \
*___op = ___r; \
likely(___r == ___o); \
})
#endif /* try_cmpxchg_relaxed */
#else /* try_cmpxchg_relaxed */
#ifndef try_cmpxchg_acquire
#define try_cmpxchg_acquire(...) \
__atomic_op_acquire(try_cmpxchg, __VA_ARGS__)
#endif
#ifndef try_cmpxchg_release
#define try_cmpxchg_release(...) \
__atomic_op_release(try_cmpxchg, __VA_ARGS__)
#endif
#ifndef try_cmpxchg
#define try_cmpxchg(...) \
__atomic_op_fence(try_cmpxchg, __VA_ARGS__)
#endif
#endif /* try_cmpxchg_relaxed */
#define arch_atomic_read atomic_read
#define arch_atomic_read_acquire atomic_read_acquire
@ -2522,4 +2592,4 @@ atomic64_dec_if_positive(atomic64_t *v)
#endif
#endif /* _LINUX_ATOMIC_FALLBACK_H */
// 9d95b56f98d82a2a26c7b79ccdd0c47572d50a6f
// d78e6c293c661c15188f0ec05bce45188c8d5892

129
include/linux/freelist.h Normal file
View file

@ -0,0 +1,129 @@
/* SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause */
#ifndef FREELIST_H
#define FREELIST_H
#include <linux/atomic.h>
/*
* Copyright: cameron@moodycamel.com
*
* A simple CAS-based lock-free free list. Not the fastest thing in the world
* under heavy contention, but simple and correct (assuming nodes are never
* freed until after the free list is destroyed), and fairly speedy under low
* contention.
*
* Adapted from: https://moodycamel.com/blog/2014/solving-the-aba-problem-for-lock-free-free-lists
*/
struct freelist_node {
atomic_t refs;
struct freelist_node *next;
};
struct freelist_head {
struct freelist_node *head;
};
#define REFS_ON_FREELIST 0x80000000
#define REFS_MASK 0x7FFFFFFF
static inline void __freelist_add(struct freelist_node *node, struct freelist_head *list)
{
/*
* Since the refcount is zero, and nobody can increase it once it's
* zero (except us, and we run only one copy of this method per node at
* a time, i.e. the single thread case), then we know we can safely
* change the next pointer of the node; however, once the refcount is
* back above zero, then other threads could increase it (happens under
* heavy contention, when the refcount goes to zero in between a load
* and a refcount increment of a node in try_get, then back up to
* something non-zero, then the refcount increment is done by the other
* thread) -- so if the CAS to add the node to the actual list fails,
* decrese the refcount and leave the add operation to the next thread
* who puts the refcount back to zero (which could be us, hence the
* loop).
*/
struct freelist_node *head = READ_ONCE(list->head);
for (;;) {
WRITE_ONCE(node->next, head);
atomic_set_release(&node->refs, 1);
if (!try_cmpxchg_release(&list->head, &head, node)) {
/*
* Hmm, the add failed, but we can only try again when
* the refcount goes back to zero.
*/
if (atomic_fetch_add_release(REFS_ON_FREELIST - 1, &node->refs) == 1)
continue;
}
return;
}
}
static inline void freelist_add(struct freelist_node *node, struct freelist_head *list)
{
/*
* We know that the should-be-on-freelist bit is 0 at this point, so
* it's safe to set it using a fetch_add.
*/
if (!atomic_fetch_add_release(REFS_ON_FREELIST, &node->refs)) {
/*
* Oh look! We were the last ones referencing this node, and we
* know we want to add it to the free list, so let's do it!
*/
__freelist_add(node, list);
}
}
static inline struct freelist_node *freelist_try_get(struct freelist_head *list)
{
struct freelist_node *prev, *next, *head = smp_load_acquire(&list->head);
unsigned int refs;
while (head) {
prev = head;
refs = atomic_read(&head->refs);
if ((refs & REFS_MASK) == 0 ||
!atomic_try_cmpxchg_acquire(&head->refs, &refs, refs+1)) {
head = smp_load_acquire(&list->head);
continue;
}
/*
* Good, reference count has been incremented (it wasn't at
* zero), which means we can read the next and not worry about
* it changing between now and the time we do the CAS.
*/
next = READ_ONCE(head->next);
if (try_cmpxchg_acquire(&list->head, &head, next)) {
/*
* Yay, got the node. This means it was on the list,
* which means should-be-on-freelist must be false no
* matter the refcount (because nobody else knows it's
* been taken off yet, it can't have been put back on).
*/
WARN_ON_ONCE(atomic_read(&head->refs) & REFS_ON_FREELIST);
/*
* Decrease refcount twice, once for our ref, and once
* for the list's ref.
*/
atomic_fetch_add(-2, &head->refs);
return head;
}
/*
* OK, the head must have changed on us, but we still need to decrement
* the refcount we increased.
*/
refs = atomic_fetch_add(-1, &prev->refs);
if (refs == REFS_ON_FREELIST + 1)
__freelist_add(prev, list);
}
return NULL;
}
#endif /* FREELIST_H */

25
include/linux/kprobes.h
View file

@ -27,6 +27,8 @@
#include <linux/rcupdate.h>
#include <linux/mutex.h>
#include <linux/ftrace.h>
#include <linux/refcount.h>
#include <linux/freelist.h>
#include <asm/kprobes.h>
#ifdef CONFIG_KPROBES
@ -144,6 +146,11 @@ static inline int kprobe_ftrace(struct kprobe *p)
* ignored, due to maxactive being too low.
*
*/
struct kretprobe_holder {
struct kretprobe *rp;
refcount_t ref;
};
struct kretprobe {
struct kprobe kp;
kretprobe_handler_t handler;
@ -151,18 +158,18 @@ struct kretprobe {
int maxactive;
int nmissed;
size_t data_size;
struct hlist_head free_instances;
raw_spinlock_t lock;
struct freelist_head freelist;
struct kretprobe_holder *rph;
};
struct kretprobe_instance {
union {
struct hlist_node hlist;
struct freelist_node freelist;
struct rcu_head rcu;
};
struct kretprobe *rp;
struct llist_node llist;
struct kretprobe_holder *rph;
kprobe_opcode_t *ret_addr;
struct task_struct *task;
void *fp;
char data[];
};
@ -221,6 +228,14 @@ unsigned long kretprobe_trampoline_handler(struct pt_regs *regs,
return ret;
}
static nokprobe_inline struct kretprobe *get_kretprobe(struct kretprobe_instance *ri)
{
RCU_LOCKDEP_WARN(!rcu_read_lock_any_held(),
"Kretprobe is accessed from instance under preemptive context");
return READ_ONCE(ri->rph->rp);
}
#else /* CONFIG_KRETPROBES */
static inline void arch_prepare_kretprobe(struct kretprobe *rp,
struct pt_regs *regs)

23
include/linux/llist.h
View file

@ -197,6 +197,16 @@ static inline struct llist_node *llist_next(struct llist_node *node)
extern bool llist_add_batch(struct llist_node *new_first,
struct llist_node *new_last,
struct llist_head *head);
static inline bool __llist_add_batch(struct llist_node *new_first,
struct llist_node *new_last,
struct llist_head *head)
{
new_last->next = head->first;
head->first = new_first;
return new_last->next == NULL;
}
/**
* llist_add - add a new entry
* @new: new entry to be added
@ -209,6 +219,11 @@ static inline bool llist_add(struct llist_node *new, struct llist_head *head)
return llist_add_batch(new, new, head);
}
static inline bool __llist_add(struct llist_node *new, struct llist_head *head)
{
return __llist_add_batch(new, new, head);
}
/**
* llist_del_all - delete all entries from lock-less list
* @head: the head of lock-less list to delete all entries
@ -222,6 +237,14 @@ static inline struct llist_node *llist_del_all(struct llist_head *head)
return xchg(&head->first, NULL);
}
static inline struct llist_node *__llist_del_all(struct llist_head *head)
{
struct llist_node *first = head->first;
head->first = NULL;
return first;
}
extern struct llist_node *llist_del_first(struct llist_head *head);
struct llist_node *llist_reverse_order(struct llist_node *head);

4
include/linux/sched.h
View file

@ -1350,6 +1350,10 @@ struct task_struct {
struct callback_head mce_kill_me;
#endif
#ifdef CONFIG_KRETPROBES
struct llist_head kretprobe_instances;
#endif
/*
* New fields for task_struct should be added above here, so that
* they are included in the randomized portion of task_struct.

4
kernel/fork.c
View file

@ -2183,6 +2183,10 @@ static __latent_entropy struct task_struct *copy_process(
INIT_LIST_HEAD(&p->thread_group);
p->task_works = NULL;
#ifdef CONFIG_KRETPROBES
p->kretprobe_instances.first = NULL;
#endif
/*
* Ensure that the cgroup subsystem policies allow the new process to be
* forked. It should be noted that the new process's css_set can be changed

320
kernel/kprobes.c
View file

@ -36,7 +36,6 @@
#include <linux/cpu.h>
#include <linux/jump_label.h>
#include <linux/perf_event.h>
#include <linux/static_call.h>
#include <asm/sections.h>
#include <asm/cacheflush.h>
@ -54,7 +53,6 @@ static int kprobes_initialized;
* - RCU hlist traversal under disabling preempt (breakpoint handlers)
*/
static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE];
static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE];
/* NOTE: change this value only with kprobe_mutex held */
static bool kprobes_all_disarmed;
@ -62,9 +60,6 @@ static bool kprobes_all_disarmed;
/* This protects kprobe_table and optimizing_list */
static DEFINE_MUTEX(kprobe_mutex);
static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
static struct {
raw_spinlock_t lock ____cacheline_aligned_in_smp;
} kretprobe_table_locks[KPROBE_TABLE_SIZE];
kprobe_opcode_t * __weak kprobe_lookup_name(const char *name,
unsigned int __unused)
@ -72,11 +67,6 @@ kprobe_opcode_t * __weak kprobe_lookup_name(const char *name,
return ((kprobe_opcode_t *)(kallsyms_lookup_name(name)));
}
static raw_spinlock_t *kretprobe_table_lock_ptr(unsigned long hash)
{
return &(kretprobe_table_locks[hash].lock);
}
/* Blacklist -- list of struct kprobe_blacklist_entry */
static LIST_HEAD(kprobe_blacklist);
@ -1224,77 +1214,27 @@ void kprobes_inc_nmissed_count(struct kprobe *p)
}
NOKPROBE_SYMBOL(kprobes_inc_nmissed_count);
static void free_rp_inst_rcu(struct rcu_head *head)
{
struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu);
if (refcount_dec_and_test(&ri->rph->ref))
kfree(ri->rph);
kfree(ri);
}
NOKPROBE_SYMBOL(free_rp_inst_rcu);
static void recycle_rp_inst(struct kretprobe_instance *ri)
{
struct kretprobe *rp = ri->rp;
struct kretprobe *rp = get_kretprobe(ri);
/* remove rp inst off the rprobe_inst_table */
hlist_del(&ri->hlist);
INIT_HLIST_NODE(&ri->hlist);
if (likely(rp)) {
raw_spin_lock(&rp->lock);
hlist_add_head(&ri->hlist, &rp->free_instances);
raw_spin_unlock(&rp->lock);
freelist_add(&ri->freelist, &rp->freelist);
} else
kfree_rcu(ri, rcu);
call_rcu(&ri->rcu, free_rp_inst_rcu);
}
NOKPROBE_SYMBOL(recycle_rp_inst);
static void kretprobe_hash_lock(struct task_struct *tsk,
struct hlist_head **head, unsigned long *flags)
__acquires(hlist_lock)
{
unsigned long hash = hash_ptr(tsk, KPROBE_HASH_BITS);
raw_spinlock_t *hlist_lock;
*head = &kretprobe_inst_table[hash];
hlist_lock = kretprobe_table_lock_ptr(hash);
/*
* Nested is a workaround that will soon not be needed.
* There's other protections that make sure the same lock
* is not taken on the same CPU that lockdep is unaware of.
* Differentiate when it is taken in NMI context.
*/
raw_spin_lock_irqsave_nested(hlist_lock, *flags, !!in_nmi());
}
NOKPROBE_SYMBOL(kretprobe_hash_lock);
static void kretprobe_table_lock(unsigned long hash,
unsigned long *flags)
__acquires(hlist_lock)
{
raw_spinlock_t *hlist_lock = kretprobe_table_lock_ptr(hash);
/*
* Nested is a workaround that will soon not be needed.
* There's other protections that make sure the same lock
* is not taken on the same CPU that lockdep is unaware of.
* Differentiate when it is taken in NMI context.
*/
raw_spin_lock_irqsave_nested(hlist_lock, *flags, !!in_nmi());
}
NOKPROBE_SYMBOL(kretprobe_table_lock);
static void kretprobe_hash_unlock(struct task_struct *tsk,
unsigned long *flags)
__releases(hlist_lock)
{
unsigned long hash = hash_ptr(tsk, KPROBE_HASH_BITS);
raw_spinlock_t *hlist_lock;
hlist_lock = kretprobe_table_lock_ptr(hash);
raw_spin_unlock_irqrestore(hlist_lock, *flags);
}
NOKPROBE_SYMBOL(kretprobe_hash_unlock);
static void kretprobe_table_unlock(unsigned long hash,
unsigned long *flags)
__releases(hlist_lock)
{
raw_spinlock_t *hlist_lock = kretprobe_table_lock_ptr(hash);
raw_spin_unlock_irqrestore(hlist_lock, *flags);
}
NOKPROBE_SYMBOL(kretprobe_table_unlock);
static struct kprobe kprobe_busy = {
.addr = (void *) get_kprobe,
};
@ -1324,24 +1264,21 @@ void kprobe_busy_end(void)
void kprobe_flush_task(struct task_struct *tk)
{
struct kretprobe_instance *ri;
struct hlist_head *head;
struct hlist_node *tmp;
unsigned long hash, flags = 0;
struct llist_node *node;
/* Early boot, not yet initialized. */
if (unlikely(!kprobes_initialized))
/* Early boot. kretprobe_table_locks not yet initialized. */
return;
kprobe_busy_begin();
hash = hash_ptr(tk, KPROBE_HASH_BITS);
head = &kretprobe_inst_table[hash];
kretprobe_table_lock(hash, &flags);
hlist_for_each_entry_safe(ri, tmp, head, hlist) {
if (ri->task == tk)
recycle_rp_inst(ri);
node = __llist_del_all(&tk->kretprobe_instances);
while (node) {
ri = container_of(node, struct kretprobe_instance, llist);
node = node->next;
recycle_rp_inst(ri);
}
kretprobe_table_unlock(hash, &flags);
kprobe_busy_end();
}
@ -1350,38 +1287,24 @@ NOKPROBE_SYMBOL(kprobe_flush_task);
static inline void free_rp_inst(struct kretprobe *rp)
{
struct kretprobe_instance *ri;
struct hlist_node *next;
struct freelist_node *node;
int count = 0;
node = rp->freelist.head;
while (node) {
ri = container_of(node, struct kretprobe_instance, freelist);
node = node->next;
hlist_for_each_entry_safe(ri, next, &rp->free_instances, hlist) {
hlist_del(&ri->hlist);
kfree(ri);
count++;
}
if (refcount_sub_and_test(count, &rp->rph->ref)) {
kfree(rp->rph);
rp->rph = NULL;
}
}
static void cleanup_rp_inst(struct kretprobe *rp)
{
unsigned long flags, hash;
struct kretprobe_instance *ri;
struct hlist_node *next;
struct hlist_head *head;
/* To avoid recursive kretprobe by NMI, set kprobe busy here */
kprobe_busy_begin();
for (hash = 0; hash < KPROBE_TABLE_SIZE; hash++) {
kretprobe_table_lock(hash, &flags);
head = &kretprobe_inst_table[hash];
hlist_for_each_entry_safe(ri, next, head, hlist) {
if (ri->rp == rp)
ri->rp = NULL;
}
kretprobe_table_unlock(hash, &flags);
}
kprobe_busy_end();
free_rp_inst(rp);
}
NOKPROBE_SYMBOL(cleanup_rp_inst);
/* Add the new probe to ap->list */
static int add_new_kprobe(struct kprobe *ap, struct kprobe *p)
{
@ -1643,7 +1566,6 @@ static int check_kprobe_address_safe(struct kprobe *p,
if (!kernel_text_address((unsigned long) p->addr) ||
within_kprobe_blacklist((unsigned long) p->addr) ||
jump_label_text_reserved(p->addr, p->addr) ||
static_call_text_reserved(p->addr, p->addr) ||
find_bug((unsigned long)p->addr)) {
ret = -EINVAL;
goto out;
@ -1942,88 +1864,56 @@ unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs,
void *trampoline_address,
void *frame_pointer)
{
struct kretprobe_instance *ri = NULL, *last = NULL;
struct hlist_head *head;
struct hlist_node *tmp;
unsigned long flags;
kprobe_opcode_t *correct_ret_addr = NULL;
bool skipped = false;
struct kretprobe_instance *ri = NULL;
struct llist_node *first, *node;
struct kretprobe *rp;
kretprobe_hash_lock(current, &head, &flags);
/* Find all nodes for this frame. */
first = node = current->kretprobe_instances.first;
while (node) {
ri = container_of(node, struct kretprobe_instance, llist);
/*
* It is possible to have multiple instances associated with a given
* task either because multiple functions in the call path have
* return probes installed on them, and/or more than one
* return probe was registered for a target function.
*
* We can handle this because:
* - instances are always pushed into the head of the list
* - when multiple return probes are registered for the same
* function, the (chronologically) first instance's ret_addr
* will be the real return address, and all the rest will
* point to kretprobe_trampoline.
*/
hlist_for_each_entry(ri, head, hlist) {
if (ri->task != current)
/* another task is sharing our hash bucket */
continue;
/*
* Return probes must be pushed on this hash list correct
* order (same as return order) so that it can be popped
* correctly. However, if we find it is pushed it incorrect
* order, this means we find a function which should not be
* probed, because the wrong order entry is pushed on the
* path of processing other kretprobe itself.
*/
if (ri->fp != frame_pointer) {
if (!skipped)
pr_warn("kretprobe is stacked incorrectly. Trying to fixup.\n");
skipped = true;
continue;
}
BUG_ON(ri->fp != frame_pointer);
correct_ret_addr = ri->ret_addr;
if (skipped)
pr_warn("%ps must be blacklisted because of incorrect kretprobe order\n",
ri->rp->kp.addr);
if (correct_ret_addr != trampoline_address)
if (ri->ret_addr != trampoline_address) {
correct_ret_addr = ri->ret_addr;
/*
* This is the real return address. Any other
* instances associated with this task are for
* other calls deeper on the call stack
*/
break;
goto found;
}
node = node->next;
}
pr_err("Oops! Kretprobe fails to find correct return address.\n");
BUG_ON(1);
BUG_ON(!correct_ret_addr || (correct_ret_addr == trampoline_address));
last = ri;
found:
/* Unlink all nodes for this frame. */
current->kretprobe_instances.first = node->next;
node->next = NULL;
hlist_for_each_entry_safe(ri, tmp, head, hlist) {
if (ri->task != current)
/* another task is sharing our hash bucket */
continue;
if (ri->fp != frame_pointer)
continue;
/* Run them.. */
while (first) {
ri = container_of(first, struct kretprobe_instance, llist);
first = first->next;
if (ri->rp && ri->rp->handler) {
rp = get_kretprobe(ri);
if (rp && rp->handler) {
struct kprobe *prev = kprobe_running();
__this_cpu_write(current_kprobe, &ri->rp->kp);
__this_cpu_write(current_kprobe, &rp->kp);
ri->ret_addr = correct_ret_addr;
ri->rp->handler(ri, regs);
rp->handler(ri, regs);
__this_cpu_write(current_kprobe, prev);
}
recycle_rp_inst(ri);
if (ri == last)
break;
}
kretprobe_hash_unlock(current, &flags);
return (unsigned long)correct_ret_addr;
}
NOKPROBE_SYMBOL(__kretprobe_trampoline_handler)
@ -2035,44 +1925,26 @@ NOKPROBE_SYMBOL(__kretprobe_trampoline_handler)
static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
{
struct kretprobe *rp = container_of(p, struct kretprobe, kp);
unsigned long hash, flags = 0;
struct kretprobe_instance *ri;
struct freelist_node *fn;
/* TODO: consider to only swap the RA after the last pre_handler fired */
hash = hash_ptr(current, KPROBE_HASH_BITS);
/*
* Nested is a workaround that will soon not be needed.
* There's other protections that make sure the same lock
* is not taken on the same CPU that lockdep is unaware of.
*/
raw_spin_lock_irqsave_nested(&rp->lock, flags, 1);
if (!hlist_empty(&rp->free_instances)) {
ri = hlist_entry(rp->free_instances.first,
struct kretprobe_instance, hlist);
hlist_del(&ri->hlist);
raw_spin_unlock_irqrestore(&rp->lock, flags);
ri->rp = rp;
ri->task = current;
if (rp->entry_handler && rp->entry_handler(ri, regs)) {
raw_spin_lock_irqsave_nested(&rp->lock, flags, 1);
hlist_add_head(&ri->hlist, &rp->free_instances);
raw_spin_unlock_irqrestore(&rp->lock, flags);
return 0;
}
arch_prepare_kretprobe(ri, regs);
/* XXX(hch): why is there no hlist_move_head? */
INIT_HLIST_NODE(&ri->hlist);
kretprobe_table_lock(hash, &flags);
hlist_add_head(&ri->hlist, &kretprobe_inst_table[hash]);
kretprobe_table_unlock(hash, &flags);
} else {
fn = freelist_try_get(&rp->freelist);
if (!fn) {
rp->nmissed++;
raw_spin_unlock_irqrestore(&rp->lock, flags);
return 0;
}
ri = container_of(fn, struct kretprobe_instance, freelist);
if (rp->entry_handler && rp->entry_handler(ri, regs)) {
freelist_add(&ri->freelist, &rp->freelist);
return 0;
}
arch_prepare_kretprobe(ri, regs);
__llist_add(&ri->llist, &current->kretprobe_instances);
return 0;
}
NOKPROBE_SYMBOL(pre_handler_kretprobe);
@ -2129,18 +2001,24 @@ int register_kretprobe(struct kretprobe *rp)
rp->maxactive = num_possible_cpus();
#endif
}
raw_spin_lock_init(&rp->lock);
INIT_HLIST_HEAD(&rp->free_instances);
rp->freelist.head = NULL;
rp->rph = kzalloc(sizeof(struct kretprobe_holder), GFP_KERNEL);
if (!rp->rph)
return -ENOMEM;
rp->rph->rp = rp;
for (i = 0; i < rp->maxactive; i++) {
inst = kmalloc(sizeof(struct kretprobe_instance) +
inst = kzalloc(sizeof(struct kretprobe_instance) +
rp->data_size, GFP_KERNEL);
if (inst == NULL) {
refcount_set(&rp->rph->ref, i);
free_rp_inst(rp);
return -ENOMEM;
}
INIT_HLIST_NODE(&inst->hlist);
hlist_add_head(&inst->hlist, &rp->free_instances);
inst->rph = rp->rph;
freelist_add(&inst->freelist, &rp->freelist);
}
refcount_set(&rp->rph->ref, i);
rp->nmissed = 0;
/* Establish function entry probe point */
@ -2182,16 +2060,18 @@ void unregister_kretprobes(struct kretprobe **rps, int num)
if (num <= 0)
return;
mutex_lock(&kprobe_mutex);
for (i = 0; i < num; i++)
for (i = 0; i < num; i++) {
if (__unregister_kprobe_top(&rps[i]->kp) < 0)
rps[i]->kp.addr = NULL;
rps[i]->rph->rp = NULL;
}
mutex_unlock(&kprobe_mutex);
synchronize_rcu();
for (i = 0; i < num; i++) {
if (rps[i]->kp.addr) {
__unregister_kprobe_bottom(&rps[i]->kp);
cleanup_rp_inst(rps[i]);
free_rp_inst(rps[i]);
}
}
}
@ -2235,9 +2115,6 @@ static void kill_kprobe(struct kprobe *p)
lockdep_assert_held(&kprobe_mutex);
if (WARN_ON_ONCE(kprobe_gone(p)))
return;
p->flags |= KPROBE_FLAG_GONE;
if (kprobe_aggrprobe(p)) {
/*
@ -2518,10 +2395,7 @@ static int kprobes_module_callback(struct notifier_block *nb,
mutex_lock(&kprobe_mutex);
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
hlist_for_each_entry(p, head, hlist) {
if (kprobe_gone(p))
continue;
hlist_for_each_entry(p, head, hlist)
if (within_module_init((unsigned long)p->addr, mod) ||
(checkcore &&
within_module_core((unsigned long)p->addr, mod))) {
@ -2538,7 +2412,6 @@ static int kprobes_module_callback(struct notifier_block *nb,
*/
kill_kprobe(p);
}
}
}
if (val == MODULE_STATE_GOING)
remove_module_kprobe_blacklist(mod);
@ -2583,11 +2456,8 @@ static int __init init_kprobes(void)
/* FIXME allocate the probe table, currently defined statically */
/* initialize all list heads */
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
for (i = 0; i < KPROBE_TABLE_SIZE; i++)
INIT_HLIST_HEAD(&kprobe_table[i]);
INIT_HLIST_HEAD(&kretprobe_inst_table[i]);
raw_spin_lock_init(&(kretprobe_table_locks[i].lock));
}
err = populate_kprobe_blacklist(__start_kprobe_blacklist,
__stop_kprobe_blacklist);

3
kernel/trace/trace_kprobe.c
View file

@ -1731,7 +1731,8 @@ NOKPROBE_SYMBOL(kprobe_dispatcher);
static int
kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
{
struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp);
struct kretprobe *rp = get_kretprobe(ri);
struct trace_kprobe *tk = container_of(rp, struct trace_kprobe, rp);
raw_cpu_inc(*tk->nhit);

63
scripts/atomic/gen-atomic-fallback.sh
View file

@ -144,15 +144,11 @@ gen_proto_order_variants()
printf "#endif /* ${basename}_relaxed */\n\n"
}
gen_xchg_fallbacks()
gen_order_fallbacks()
{
local xchg="$1"; shift
cat <<EOF
#ifndef ${xchg}_relaxed
#define ${xchg}_relaxed ${xchg}
#define ${xchg}_acquire ${xchg}
#define ${xchg}_release ${xchg}
#else /* ${xchg}_relaxed */
#ifndef ${xchg}_acquire
#define ${xchg}_acquire(...) \\
@ -169,11 +165,62 @@ cat <<EOF
__atomic_op_fence(${xchg}, __VA_ARGS__)
#endif
#endif /* ${xchg}_relaxed */
EOF
}
gen_xchg_fallbacks()
{
local xchg="$1"; shift
printf "#ifndef ${xchg}_relaxed\n"
gen_basic_fallbacks ${xchg}
printf "#else /* ${xchg}_relaxed */\n"
gen_order_fallbacks ${xchg}
printf "#endif /* ${xchg}_relaxed */\n\n"
}
gen_try_cmpxchg_fallback()
{
local order="$1"; shift;
cat <<EOF
#ifndef ${ARCH}try_cmpxchg${order}
#define ${ARCH}try_cmpxchg${order}(_ptr, _oldp, _new) \\
({ \\
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \\
___r = ${ARCH}cmpxchg${order}((_ptr), ___o, (_new)); \\
if (unlikely(___r != ___o)) \\
*___op = ___r; \\
likely(___r == ___o); \\
})
#endif /* ${ARCH}try_cmpxchg${order} */
EOF
}
gen_try_cmpxchg_fallbacks()
{
printf "#ifndef ${ARCH}try_cmpxchg_relaxed\n"
printf "#ifdef ${ARCH}try_cmpxchg\n"
gen_basic_fallbacks "${ARCH}try_cmpxchg"
printf "#endif /* ${ARCH}try_cmpxchg */\n\n"
for order in "" "_acquire" "_release" "_relaxed"; do
gen_try_cmpxchg_fallback "${order}"
done
printf "#else /* ${ARCH}try_cmpxchg_relaxed */\n"
gen_order_fallbacks "${ARCH}try_cmpxchg"
printf "#endif /* ${ARCH}try_cmpxchg_relaxed */\n\n"
}
cat << EOF
// SPDX-License-Identifier: GPL-2.0
@ -191,6 +238,8 @@ for xchg in "${ARCH}xchg" "${ARCH}cmpxchg" "${ARCH}cmpxchg64"; do
gen_xchg_fallbacks "${xchg}"
done
gen_try_cmpxchg_fallbacks
grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "${ARCH}" "atomic" "int" ${args}
done

29
scripts/atomic/gen-atomic-instrumented.sh
View file

@ -112,14 +112,31 @@ gen_xchg()
local xchg="$1"; shift
local mult="$1"; shift
if [ "${xchg%${xchg#try_cmpxchg}}" = "try_cmpxchg" ] ; then
cat <<EOF
#define ${xchg}(ptr, ...) \\
({ \\
typeof(ptr) __ai_ptr = (ptr); \\
instrument_atomic_write(__ai_ptr, ${mult}sizeof(*__ai_ptr)); \\
arch_${xchg}(__ai_ptr, __VA_ARGS__); \\
#define ${xchg}(ptr, oldp, ...) \\
({ \\
typeof(ptr) __ai_ptr = (ptr); \\
typeof(oldp) __ai_oldp = (oldp); \\
instrument_atomic_write(__ai_ptr, ${mult}sizeof(*__ai_ptr)); \\
instrument_atomic_write(__ai_oldp, ${mult}sizeof(*__ai_oldp)); \\
arch_${xchg}(__ai_ptr, __ai_oldp, __VA_ARGS__); \\
})
EOF
else
cat <<EOF
#define ${xchg}(ptr, ...) \\
({ \\
typeof(ptr) __ai_ptr = (ptr); \\
instrument_atomic_write(__ai_ptr, ${mult}sizeof(*__ai_ptr)); \\
arch_${xchg}(__ai_ptr, __VA_ARGS__); \\
})
EOF
fi
}
gen_optional_xchg()
@ -169,7 +186,7 @@ grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "atomic64" "s64" ${args}
done
for xchg in "xchg" "cmpxchg" "cmpxchg64"; do
for xchg in "xchg" "cmpxchg" "cmpxchg64" "try_cmpxchg"; do
for order in "" "_acquire" "_release" "_relaxed"; do
gen_optional_xchg "${xchg}" "${order}"
done

0
scripts/atomic/gen-atomics.sh Normal file → Executable file
View file