| Age | Commit message (Collapse) | Author |
|---|
|
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
Unfortunately, cgroup is tangled into kernfs infrastructure.
To avoid converting all kernfs-based filesystems at once,
we need to untangle the remount part of things, instead of
having it go through kernfs_sop_remount_fs(). Fortunately,
it's not hard to do.
This commit just gets cgroup/cgroup1 to use fs_context to
deliver options on mount and remount paths. Parsing those
is going to be done in the next commits; for now we do
pretty much what legacy case does.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
perf annotate:
Wei Li:
- Fix getting source line failure
perf script:
Andi Kleen:
- Handle missing fields with -F +...
perf data:
Jiri Olsa:
- Prep work to support per-cpu files in a directory.
Intel PT:
Adrian Hunter:
- Improve thread_stack__no_call_return()
- Hide x86 retpolines in thread stacks.
- exported SQL viewer refactorings, new 'top calls' report..
Alexander Shishkin:
- Copy parent's address filter offsets on clone
- Fix address filters for vmas with non-zero offset. Applies to
ARM's CoreSight as well.
python scripts:
Tony Jones:
- Python3 support for several 'perf script' python scripts.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
And move the whole lot under CONFIG_DEBUG_LOCKDEP.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
The following commit:
87915adc3f0a ("workqueue: re-add lockdep dependencies for flushing")
improved deadlock checking in the workqueue implementation. Unfortunately
that patch also introduced a few false positive lockdep complaints.
This patch suppresses these false positives by allocating the workqueue mutex
lockdep key dynamically.
An example of a false positive lockdep complaint suppressed by this patch
can be found below. The root cause of the lockdep complaint shown below
is that the direct I/O code can call alloc_workqueue() from inside a work
item created by another alloc_workqueue() call and that both workqueues
share the same lockdep key. This patch avoids that that lockdep complaint
is triggered by allocating the work queue lockdep keys dynamically.
In other words, this patch guarantees that a unique lockdep key is
associated with each work queue mutex.
======================================================
WARNING: possible circular locking dependency detected
4.19.0-dbg+ #1 Not tainted
fio/4129 is trying to acquire lock:
00000000a01cfe1a ((wq_completion)"dio/%s"sb->s_id){+.+.}, at: flush_workqueue+0xd0/0x970
but task is already holding lock:
00000000a0acecf9 (&sb->s_type->i_mutex_key#14){+.+.}, at: ext4_file_write_iter+0x154/0x710
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&sb->s_type->i_mutex_key#14){+.+.}:
down_write+0x3d/0x80
__generic_file_fsync+0x77/0xf0
ext4_sync_file+0x3c9/0x780
vfs_fsync_range+0x66/0x100
dio_complete+0x2f5/0x360
dio_aio_complete_work+0x1c/0x20
process_one_work+0x481/0x9f0
worker_thread+0x63/0x5a0
kthread+0x1cf/0x1f0
ret_from_fork+0x24/0x30
-> #1 ((work_completion)(&dio->complete_work)){+.+.}:
process_one_work+0x447/0x9f0
worker_thread+0x63/0x5a0
kthread+0x1cf/0x1f0
ret_from_fork+0x24/0x30
-> #0 ((wq_completion)"dio/%s"sb->s_id){+.+.}:
lock_acquire+0xc5/0x200
flush_workqueue+0xf3/0x970
drain_workqueue+0xec/0x220
destroy_workqueue+0x23/0x350
sb_init_dio_done_wq+0x6a/0x80
do_blockdev_direct_IO+0x1f33/0x4be0
__blockdev_direct_IO+0x79/0x86
ext4_direct_IO+0x5df/0xbb0
generic_file_direct_write+0x119/0x220
__generic_file_write_iter+0x131/0x2d0
ext4_file_write_iter+0x3fa/0x710
aio_write+0x235/0x330
io_submit_one+0x510/0xeb0
__x64_sys_io_submit+0x122/0x340
do_syscall_64+0x71/0x220
entry_SYSCALL_64_after_hwframe+0x49/0xbe
other info that might help us debug this:
Chain exists of:
(wq_completion)"dio/%s"sb->s_id --> (work_completion)(&dio->complete_work) --> &sb->s_type->i_mutex_key#14
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sb->s_type->i_mutex_key#14);
lock((work_completion)(&dio->complete_work));
lock(&sb->s_type->i_mutex_key#14);
lock((wq_completion)"dio/%s"sb->s_id);
*** DEADLOCK ***
1 lock held by fio/4129:
#0: 00000000a0acecf9 (&sb->s_type->i_mutex_key#14){+.+.}, at: ext4_file_write_iter+0x154/0x710
stack backtrace:
CPU: 3 PID: 4129 Comm: fio Not tainted 4.19.0-dbg+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
Call Trace:
dump_stack+0x86/0xc5
print_circular_bug.isra.32+0x20a/0x218
__lock_acquire+0x1c68/0x1cf0
lock_acquire+0xc5/0x200
flush_workqueue+0xf3/0x970
drain_workqueue+0xec/0x220
destroy_workqueue+0x23/0x350
sb_init_dio_done_wq+0x6a/0x80
do_blockdev_direct_IO+0x1f33/0x4be0
__blockdev_direct_IO+0x79/0x86
ext4_direct_IO+0x5df/0xbb0
generic_file_direct_write+0x119/0x220
__generic_file_write_iter+0x131/0x2d0
ext4_file_write_iter+0x3fa/0x710
aio_write+0x235/0x330
io_submit_one+0x510/0xeb0
__x64_sys_io_submit+0x122/0x340
do_syscall_64+0x71/0x220
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes.berg@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/20190214230058.196511-20-bvanassche@acm.org
[ Reworked the changelog a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
A shortcoming of the current lockdep implementation is that it requires
lock keys to be allocated statically. That forces all instances of lock
objects that occur in a given data structure to share a lock key. Since
lock dependency analysis groups lock objects per key sharing lock keys
can cause false positive lockdep reports. Make it possible to avoid
such false positive reports by allowing lock keys to be allocated
dynamically. Require that dynamically allocated lock keys are
registered before use by calling lockdep_register_key(). Complain about
attempts to register the same lock key pointer twice without calling
lockdep_unregister_key() between successive registration calls.
The purpose of the new lock_keys_hash[] data structure that keeps
track of all dynamic keys is twofold:
- Verify whether the lockdep_register_key() and lockdep_unregister_key()
functions are used correctly.
- Avoid that lockdep_init_map() complains when encountering a dynamically
allocated key.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-19-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
class keys
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-18-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Debugging lockdep data structure inconsistencies is challenging. Add
code that verifies data structure consistency at runtime. That code is
disabled by default because it is very CPU intensive.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-17-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
A previous patch introduced a lock chain leak. Fix that leak by reusing
lock chains that have been freed.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-16-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Reflect that add_chain_cache() is always called with the graph lock held.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-15-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
This patch does not change any functionality but makes the next patch in
this series easier to read.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-14-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Instead of abandoning elements of list_entries[] that are no longer in
use, make alloc_list_entry() reuse array elements that have been freed.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-13-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Instead of leaving lock classes that are no longer in use in the
lock_classes array, reuse entries from that array that are no longer in
use. Maintain a linked list of free lock classes with list head
'free_lock_class'. Only add freed lock classes to the free_lock_classes
list after a grace period to avoid that a lock_classes[] element would
be reused while an RCU reader is accessing it. Since the lockdep
selftests run in a context where sleeping is not allowed and since the
selftests require that lock resetting/zapping works with debug_locks
off, make the behavior of lockdep_free_key_range() and
lockdep_reset_lock() depend on whether or not these are called from
the context of the lockdep selftests.
Thanks to Peter for having shown how to modify get_pending_free()
such that that function does not have to sleep.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-12-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
synchronize_sched() has been removed recently. Update the comments that
refer to synchronize_sched().
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Fixes: 51959d85f32d ("lockdep: Replace synchronize_sched() with synchronize_rcu()") # v5.0-rc1
Link: https://lkml.kernel.org/r/20190214230058.196511-11-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
The patch that frees unused lock classes will modify the behavior of
lockdep_free_key_range() and lockdep_reset_lock() depending on whether
or not these functions are called from the context of the lockdep
selftests. Hence make it easy to detect whether or not lockdep code
is called from the context of a lockdep selftest.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-10-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
This patch does not change the behavior of these functions but makes the
patch that frees unused lock classes easier to read.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-9-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
This patch does not change any functionality. A later patch will reuse
lock classes that have been freed. In combination with that patch this
patch wil have the effect of initializing lock class order lists once
instead of every time a lock class structure is reinitialized.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-8-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Make sure that all lock order entries that refer to a class are removed
from the list_entries[] array when a kernel module is unloaded.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-7-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Make sure that add_chain_cache() returns 0 and does not modify the
chain hash if nr_chain_hlocks == MAX_LOCKDEP_CHAIN_HLOCKS before this
function is called.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-5-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Lock chains are only tracked with CONFIG_PROVE_LOCKING=y. Do not report
the memory required for the lock chain array if CONFIG_PROVE_LOCKING=n.
See also commit:
ca58abcb4a6d ("lockdep: sanitise CONFIG_PROVE_LOCKING")
Include the size of the chain_hlocks[] array.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-4-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Change the sizeof(array element time) * (array size) expressions into
sizeof(array). This fixes the size computations of the classhash_table[]
and chainhash_table[] arrays.
The reason is that commit:
a63f38cc4ccf ("locking/lockdep: Convert hash tables to hlists")
changed the type of the elements of that array from 'struct list_head' into
'struct hlist_head'.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-3-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use %zu to format size_t instead of %lu to avoid that the compiler
complains about a mismatch between format specifier and argument on
32-bit systems.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-2-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
With the > 4 nesting levels case handled by the commit:
d682b596d993 ("locking/qspinlock: Handle > 4 slowpath nesting levels")
the BUG_ON() call in encode_tail() will never actually be triggered.
Remove it.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1551057253-3231-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Commit d83525ca62cf ("bpf: introduce bpf_spin_lock")
introduced bpf_spin_lock and the field spin_lock_off
in kernel internal structure bpf_map has the following
meaning:
>=0 valid offset, <0 error
For every map created, the kernel will ensure
spin_lock_off has correct value.
Currently, bpf_map->spin_lock_off is not copied
from the inner map to the map_in_map inner_map_meta
during a map_in_map type map creation, so
inner_map_meta->spin_lock_off = 0.
This will give verifier wrong information that
inner_map has bpf_spin_lock and the bpf_spin_lock
is defined at offset 0. An access to offset 0
of a value pointer will trigger the following error:
bpf_spin_lock cannot be accessed directly by load/store
This patch fixed the issue by copy inner map's spin_lock_off
value to inner_map_meta->spin_lock_off.
Fixes: d83525ca62cf ("bpf: introduce bpf_spin_lock")
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
Return bpf program run_time_ns and run_cnt via bpf_prog_info
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
|
|
JITed BPF programs are indistinguishable from kernel functions, but unlike
kernel code BPF code can be changed often.
Typical approach of "perf record" + "perf report" profiling and tuning of
kernel code works just as well for BPF programs, but kernel code doesn't
need to be monitored whereas BPF programs do.
Users load and run large amount of BPF programs.
These BPF stats allow tools monitor the usage of BPF on the server.
The monitoring tools will turn sysctl kernel.bpf_stats_enabled
on and off for few seconds to sample average cost of the programs.
Aggregated data over hours and days will provide an insight into cost of BPF
and alarms can trigger in case given program suddenly gets more expensive.
The cost of two sched_clock() per program invocation adds ~20 nsec.
Fast BPF progs (like selftests/bpf/progs/test_pkt_access.c) will slow down
from ~10 nsec to ~30 nsec.
static_key minimizes the cost of the stats collection.
There is no measurable difference before/after this patch
with kernel.bpf_stats_enabled=0
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
|
|
Since -Wmaybe-uninitialized was introduced by GCC 4.7, we have patched
various false positives:
- commit e74fc973b6e5 ("Turn off -Wmaybe-uninitialized when building
with -Os") turned off this option for -Os.
- commit 815eb71e7149 ("Kbuild: disable 'maybe-uninitialized' warning
for CONFIG_PROFILE_ALL_BRANCHES") turned off this option for
CONFIG_PROFILE_ALL_BRANCHES
- commit a76bcf557ef4 ("Kbuild: enable -Wmaybe-uninitialized warning
for "make W=1"") turned off this option for GCC < 4.9
Arnd provided more explanation in https://lkml.org/lkml/2017/3/14/903
I think this looks better by shifting the logic from Makefile to Kconfig.
Link: https://github.com/ClangBuiltLinux/linux/issues/350
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
|
|
In bpf/syscall.c, bpf_map_get_fd_by_id() use bpf_map_inc_not_zero()
to increase the refcount, both map->refcnt and map->usercnt. Then, if
bpf_map_new_fd() fails, should handle map->usercnt too.
Fixes: bd5f5f4ecb78 ("bpf: Add BPF_MAP_GET_FD_BY_ID")
Signed-off-by: Peng Sun <sironhide0null@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
|
|
Three conflicts, one of which, for marvell10g.c is non-trivial and
requires some follow-up from Heiner or someone else.
The issue is that Heiner converted the marvell10g driver over to
use the generic c45 code as much as possible.
However, in 'net' a bug fix appeared which makes sure that a new
local mask (MDIO_AN_10GBT_CTRL_ADV_NBT_MASK) with value 0x01e0
is cleared.
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Pull networking fixes from David Miller:
"Hopefully the last pull request for this release. Fingers crossed:
1) Only refcount ESP stats on full sockets, from Martin Willi.
2) Missing barriers in AF_UNIX, from Al Viro.
3) RCU protection fixes in ipv6 route code, from Paolo Abeni.
4) Avoid false positives in untrusted GSO validation, from Willem de
Bruijn.
5) Forwarded mesh packets in mac80211 need more tailroom allocated,
from Felix Fietkau.
6) Use operstate consistently for linkup in team driver, from George
Wilkie.
7) ThunderX bug fixes from Vadim Lomovtsev. Mostly races between VF
and PF code paths.
8) Purge ipv6 exceptions during netdevice removal, from Paolo Abeni.
9) nfp eBPF code gen fixes from Jiong Wang.
10) bnxt_en firmware timeout fix from Michael Chan.
11) Use after free in udp/udpv6 error handlers, from Paolo Abeni.
12) Fix a race in x25_bind triggerable by syzbot, from Eric Dumazet"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (65 commits)
net: phy: realtek: Dummy IRQ calls for RTL8366RB
tcp: repaired skbs must init their tso_segs
net/x25: fix a race in x25_bind()
net: dsa: Remove documentation for port_fdb_prepare
Revert "bridge: do not add port to router list when receives query with source 0.0.0.0"
selftests: fib_tests: sleep after changing carrier. again.
net: set static variable an initial value in atl2_probe()
net: phy: marvell10g: Fix Multi-G advertisement to only advertise 10G
bpf, doc: add bpf list as secondary entry to maintainers file
udp: fix possible user after free in error handler
udpv6: fix possible user after free in error handler
fou6: fix proto error handler argument type
udpv6: add the required annotation to mib type
mdio_bus: Fix use-after-free on device_register fails
net: Set rtm_table to RT_TABLE_COMPAT for ipv6 for tables > 255
bnxt_en: Wait longer for the firmware message response to complete.
bnxt_en: Fix typo in firmware message timeout logic.
nfp: bpf: fix ALU32 high bits clearance bug
nfp: bpf: fix code-gen bug on BPF_ALU | BPF_XOR | BPF_K
Documentation: networking: switchdev: Update port parent ID section
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates from Marc Zyngier
- Core pseudo-NMI handling code
- Allow the default irq domain to be retrieved
- A new interrupt controller for the Loongson LS1X platform
- Affinity support for the SiFive PLIC
- Better support for the iMX irqsteer driver
- NUMA aware memory allocations for GICv3
- A handful of other fixes (i8259, GICv3, PLIC)
|
|
Daniel Borkmann says:
====================
pull-request: bpf 2019-02-23
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix a bug in BPF's LPM deletion logic to match correct prefix
length, from Alban.
2) Fix AF_XDP teardown by not destroying umem prematurely as it
is still needed till all outstanding skbs are freed, from Björn.
3) Fix unkillable BPF_PROG_TEST_RUN under preempt kernel by checking
signal_pending() outside need_resched() condition which is never
triggered there, from Stanislav.
4) Fix two nfp JIT bugs, one in code emission for K-based xor, and
another one to explicitly clear upper bits in alu32, from Jiong.
5) Add bpf list address to maintainers file, from Daniel.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Currently, the address range calculation for file-based filters works as
long as the vma that maps the matching part of the object file starts
from offset zero into the file (vm_pgoff==0). Otherwise, the resulting
filter range would be off by vm_pgoff pages. Another related problem is
that in case of a partially matching vma, that is, a vma that matches
part of a filter region, the filter range size wouldn't be adjusted.
Fix the arithmetics around address filter range calculations, taking
into account vma offset, so that the entire calculation is done before
the filter configuration is passed to the PMU drivers instead of having
those drivers do the final bit of arithmetics.
Based on the patch by Adrian Hunter <adrian.hunter.intel.com>.
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Fixes: 375637bc5249 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20190215115655.63469-3-alexander.shishkin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
When a child event is allocated in the inherit_event() path, the VMA
based filter offsets are not copied from the parent, even though the
address space mapping of the new task remains the same, which leads to
no trace for the new task until exec.
Reported-by: Mansour Alharthi <malharthi9@gatech.edu>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Fixes: 375637bc5249 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20190215115655.63469-2-alexander.shishkin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
trie_delete_elem() was deleting an entry even though it was not matching
if the prefixlen was correct. This patch adds a check on matchlen.
Reproducer:
$ sudo bpftool map create /sys/fs/bpf/mylpm type lpm_trie key 8 value 1 entries 128 name mylpm flags 1
$ sudo bpftool map update pinned /sys/fs/bpf/mylpm key hex 10 00 00 00 aa bb cc dd value hex 01
$ sudo bpftool map dump pinned /sys/fs/bpf/mylpm
key: 10 00 00 00 aa bb cc dd value: 01
Found 1 element
$ sudo bpftool map delete pinned /sys/fs/bpf/mylpm key hex 10 00 00 00 ff ff ff ff
$ echo $?
0
$ sudo bpftool map dump pinned /sys/fs/bpf/mylpm
Found 0 elements
A similar reproducer is added in the selftests.
Without the patch:
$ sudo ./tools/testing/selftests/bpf/test_lpm_map
test_lpm_map: test_lpm_map.c:485: test_lpm_delete: Assertion `bpf_map_delete_elem(map_fd, key) == -1 && errno == ENOENT' failed.
Aborted
With the patch: test_lpm_map runs without errors.
Fixes: e454cf595853 ("bpf: Implement map_delete_elem for BPF_MAP_TYPE_LPM_TRIE")
Cc: Craig Gallek <kraig@google.com>
Signed-off-by: Alban Crequy <alban@kinvolk.io>
Acked-by: Craig Gallek <kraig@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
|
|
All BPF programs must be called with preemption disabled.
Fixes: 568f196756ad ("bpf: check that BPF programs run with preemption disabled")
Reported-by: syzbot+8bf19ee2aa580de7a2a7@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
|
|
We've been seeing hard-to-trigger psi crashes when running inside VM
instances:
divide error: 0000 [#1] SMP PTI
Modules linked in: [...]
CPU: 0 PID: 212 Comm: kworker/0:2 Not tainted 4.16.18-119_fbk9_3817_gfe944c98d695 #119
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
Workqueue: events psi_clock
RIP: 0010:psi_update_stats+0x270/0x490
RSP: 0018:ffffc90001117e10 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8800a35a13f8
RDX: 0000000000000000 RSI: ffff8800a35a1340 RDI: 0000000000000000
RBP: 0000000000000658 R08: ffff8800a35a1470 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00000000000f8502
FS: 0000000000000000(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe370fa000 CR3: 00000000b1e3a000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
psi_clock+0x12/0x50
process_one_work+0x1e0/0x390
worker_thread+0x2b/0x3c0
? rescuer_thread+0x330/0x330
kthread+0x113/0x130
? kthread_create_worker_on_cpu+0x40/0x40
? SyS_exit_group+0x10/0x10
ret_from_fork+0x35/0x40
Code: 48 0f 47 c7 48 01 c2 45 85 e4 48 89 16 0f 85 e6 00 00 00 4c 8b 49 10 4c 8b 51 08 49 69 d9 f2 07 00 00 48 6b c0 64 4c 8b 29 31 d2 <48> f7 f7 49 69 d5 8d 06 00 00 48 89 c5 4c 69 f0 00 98 0b 00 48
The Code-line points to `period` being 0 inside update_stats(), and we
divide by that when calculating that period's pressure percentage.
The elapsed period should never be 0. The reason this can happen is due
to an off-by-one in the idle time / missing period calculation combined
with a coarse sched_clock() in the virtual machine.
The target time for aggregation is advanced into the future on a fixed
grid to prevent clock drift. So when an aggregation runs after some idle
period, we can not just set it to "now + psi_period", but have to
calculate the downtime and advance the target time relative to itself.
However, if the aggregator was disabled exactly one psi_period (ns), we
drop one idle period in the calculation due to a > when we should do >=.
In that case, next_update will be advanced from 'now - psi_period' to
'now' when it should be moved to 'now + psi_period'. The run finishes
with last_update == next_update == sched_clock().
With hardware clocks, this exact nanosecond match isn't likely in the
first place; but if it does happen, the clock will still have moved on and
the period non-zero by the time the worker runs. A pointlessly short
period, but besides the extra work, no harm no foul. However, a slow
sched_clock() like we have on VMs might not have advanced either by the
time the worker runs again. And when we calculate the elapsed period, the
result, our pressure divisor, will be 0. Ouch.
Fix this by correctly handling the situation when the elapsed time between
aggregation runs is precisely two periods, and advance the expiration
timestamp correctly to period into the future.
Link: http://lkml.kernel.org/r/20190214193157.15788-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Łukasz Siudut <lsiudut@fb.com
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
qeueue/queue
Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Signed-off-by: Tejun Heo <tj@kernel.org>
|
|
The first version of this method was missing the check for
`ret == PATH_MAX`; then such a check was added, but it didn't call kfree()
on error, so there was still a small memory leak in the error case.
Fix it by using strndup_user() instead of open-coding it.
Link: http://lkml.kernel.org/r/20190220165443.152385-1-jannh@google.com
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 0eadcc7a7bc0 ("perf/core: Fix perf_uprobe_init()")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Merge hch's big DMA rework series. This is in a topic branch in case he
wants to merge it to minimise conflicts.
|
|
|
|
The default irq domain allows legacy code to create irqdomain
mappings without having to track the domain it is allocating
from. Setting the default domain is a one shot, fire and forget
operation, and no effort was made to be able to retrieve this
information at a later point in time.
Newer irqdomain APIs (the hierarchical stuff) relies on both
the irqchip code to track the irqdomain it is allocating from,
as well as some form of firmware abstraction to easily identify
which piece of HW maps to which irq domain (DT, ACPI).
For systems without such firmware (or legacy platform that are
getting dragged into the 21st century), things are a bit harder.
For these cases (and these cases only!), let's provide a way
to retrieve the default domain, allowing the use of the v2 API
without having to resort to platform-specific hacks.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
|
|
When thread1 called printk() which did not end with '\n', and then thread2
called printk() which ends with '\n' before thread1 calls pr_cont(), the
partial content saved into "struct cont" is flushed by thread2 despite the
partial content was generated by thread1. This leads to confusing output
as if the partial content was generated by thread2. Fix this problem by
passing correct caller information to log_store().
Before:
[ T8533] abcdefghijklm
[ T8533] ABCDEFGHIJKLMNOPQRSTUVWXYZ
[ T8532] nopqrstuvwxyz
[ T8532] abcdefghijklmnopqrstuvwxyz
[ T8533] abcdefghijklm
[ T8533] ABCDEFGHIJKLMNOPQRSTUVWXYZ
[ T8532] nopqrstuvwxyz
After:
[ T8507] abcdefghijklm
[ T8508] ABCDEFGHIJKLMNOPQRSTUVWXYZ
[ T8507] nopqrstuvwxyz
[ T8507] abcdefghijklmnopqrstuvwxyz
[ T8507] abcdefghijklm
[ T8508] ABCDEFGHIJKLMNOPQRSTUVWXYZ
[ T8507] nopqrstuvwxyz
Link: http://lkml.kernel.org/r/1550314773-8607-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
To: Dmitry Vyukov <dvyukov@google.com>
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
[pmladek: broke 80-column rule where it made more harm than good]
Signed-off-by: Petr Mladek <pmladek@suse.com>
|
|
There is a spelling mistake in the mini-howto help text. Fix it.
Link: http://lkml.kernel.org/r/20190217223222.16479-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Before setting tr->cond_snapshot, it must be NULL before it can be updated.
It can go to NULL when a trace event hist trigger is created or removed, and
can only be modified under the max_lock spin lock. But because it can only
be set to something other than NULL under both the max_lock spin lock as
well as the trace_types_lock, we can perform the check if it is not NULL
only under the trace_types_lock and fail out without having to grab the
max_lock spin lock.
This is very subtle, and deserves a comment.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Add a 'trace(synthetic_event_name, params)' alternative to
synthetic_event_name(params).
Currently, the syntax used for generating synthetic events is to
invoke synthetic_event_name(params) i.e. use the synthetic event name
as a function call.
Users requested a new form that more explicitly shows that the
synthetic event is in effect being traced. In this version, a new
'trace()' keyword is used, and the synthetic event name is passed in
as the first argument.
In addition, for the sake of consistency with other actions, change
the documention to emphasize the trace() form over the function-call
form, which remains documented as equivalent.
Link: http://lkml.kernel.org/r/d082773e50232a001480cf837679a1e01c1a2eb7.1550100284.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Add support for a hist:onchange($var) handler, similar to the onmax()
handler but triggering whenever there's any change in $var, not just a
max.
Link: http://lkml.kernel.org/r/dfbc7e4ada242603e9ec3f049b5ad076a07dfd03.1550100284.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Add support for hist:handlerXXX($var).snapshot(), which will take a
snapshot of the current trace buffer whenever handlerXXX is hit.
As a first user, this also adds snapshot() action support for the
onmax() handler i.e. hist:onmax($var).snapshot().
Also, the hist trigger key printing is moved into a separate function
so the snapshot() action can print a histogram key outside the
histogram display - add and use hist_trigger_print_key() for that
purpose.
Link: http://lkml.kernel.org/r/2f1a952c0dcd8aca8702ce81269581a692396d45.1550100284.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
