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charset="UTF-8" Extend get_lock_owner() in tools/perf/util/bpf_skel/lock_data.h to: - Support rt_mutex locks (LCB_F_RT) and CONFIG_PREEMPT_RT mutexes via struct rt_mutex_base and struct rt_mutex___old, masking out the low waiter bit (0x1UL). - Return NULL when a mutex has MUTEX_FLAG_HANDOFF (0x4UL) set on owner.counter and is in the middle of being handed off rather than actively held. Also add rw_semaphore.count and struct rt_mutex_base to the fallback tools/perf/util/bpf_skel/vmlinux/vmlinux.h. Signed-off-by: Ian Rogers --- tools/perf/util/bpf_skel/lock_data.h | 62 ++++++++++++++++++---- tools/perf/util/bpf_skel/vmlinux/vmlinux.h | 5 ++ 2 files changed, 58 insertions(+), 9 deletions(-) diff --git a/tools/perf/util/bpf_skel/lock_data.h b/tools/perf/util/bpf_skel/lock_data.h index 91d464ac18bd..43d8f5030bc1 100644 --- a/tools/perf/util/bpf_skel/lock_data.h +++ b/tools/perf/util/bpf_skel/lock_data.h @@ -104,11 +104,24 @@ extern struct rq runqueues __ksym __weak; # define __has_builtin(x) 0 #endif +struct mutex___non_rt { + atomic_long_t owner; +} __attribute__((preserve_access_index)); + +struct rt_mutex_base___new { + struct task_struct *owner; +} __attribute__((preserve_access_index)); + +struct rt_mutex___old { + struct task_struct *owner; +} __attribute__((preserve_access_index)); + struct rw_semaphore___old { struct task_struct *owner; } __attribute__((preserve_access_index)); struct rw_semaphore___new { + atomic_long_t count; atomic_long_t owner; } __attribute__((preserve_access_index)); @@ -146,9 +159,25 @@ static __always_inline struct task_struct *get_lock_owner(__u64 lock, __u32 flag __u64 owner = 0; if (flags & LCB_F_MUTEX) { - struct mutex *mutex = (void *)lock; - - owner = BPF_CORE_READ(mutex, owner.counter); + struct mutex___non_rt *mutex = (void *)lock; + + if (bpf_core_field_exists(mutex->owner.counter)) { + owner = BPF_CORE_READ(mutex, owner.counter); + if (owner & 0x4UL) + return NULL; + } else if (bpf_core_type_exists(struct rt_mutex_base___new)) { + struct rt_mutex_base___new *rtm = (void *)lock; + + owner = (__u64)BPF_CORE_READ(rtm, owner); + return (void *)(owner & ~1UL); + } else { + struct rt_mutex___old *rtm = (void *)lock; + + if (bpf_core_field_exists(rtm->owner)) { + owner = (__u64)BPF_CORE_READ(rtm, owner); + return (void *)(owner & ~1UL); + } + } } else if (flags == LCB_F_READ || flags == LCB_F_WRITE) { /* * Support for the BPF_TYPE_MATCHES argument to the @@ -158,20 +187,35 @@ static __always_inline struct task_struct *get_lock_owner(__u64 lock, __u32 flag */ #if __has_builtin(__builtin_preserve_type_info) && __clang_major__ >= 15 if (bpf_core_type_matches(struct rw_semaphore___old)) { - struct rw_semaphore___old *rwsem = (void *)lock; + struct rw_semaphore___old *old = (void *)lock; - owner = (unsigned long)BPF_CORE_READ(rwsem, owner); + owner = (unsigned long)BPF_CORE_READ(old, owner); } else if (bpf_core_type_matches(struct rw_semaphore___new)) { - struct rw_semaphore___new *rwsem = (void *)lock; + struct rw_semaphore___new *new = (void *)lock; - owner = BPF_CORE_READ(rwsem, owner.counter); + owner = BPF_CORE_READ(new, owner.counter); } #else /* assume new struct */ - struct rw_semaphore *rwsem = (void *)lock; + struct rw_semaphore___new *new = (void *)lock; - owner = BPF_CORE_READ(rwsem, owner.counter); + if (bpf_core_field_exists(new->owner.counter)) + owner = BPF_CORE_READ(new, owner.counter); #endif + } else if (flags == LCB_F_RT) { + if (bpf_core_type_exists(struct rt_mutex_base___new)) { + struct rt_mutex_base___new *rtm = (void *)lock; + + owner = (__u64)BPF_CORE_READ(rtm, owner); + return (void *)(owner & ~1UL); + } else { + struct rt_mutex___old *rtm = (void *)lock; + + if (bpf_core_field_exists(rtm->owner)) { + owner = (__u64)BPF_CORE_READ(rtm, owner); + return (void *)(owner & ~1UL); + } + } } if (!owner) diff --git a/tools/perf/util/bpf_skel/vmlinux/vmlinux.h b/tools/perf/util/bpf_skel/vmlinux/vmlinux.h index 94e42b022ab1..b75ddc6846bb 100644 --- a/tools/perf/util/bpf_skel/vmlinux/vmlinux.h +++ b/tools/perf/util/bpf_skel/vmlinux/vmlinux.h @@ -76,6 +76,7 @@ struct signal_struct { } __attribute__((preserve_access_index)); struct rw_semaphore { + atomic_long_t count; atomic_long_t owner; } __attribute__((preserve_access_index)); @@ -83,6 +84,10 @@ struct mutex { atomic_long_t owner; } __attribute__((preserve_access_index)); +struct rt_mutex_base { + struct task_struct *owner; +} __attribute__((preserve_access_index)); + struct kernfs_node { u64 id; } __attribute__((preserve_access_index)); -- 2.56.0.307.g5fe7bd680c-goog