I don't why we need take a single write lock and disable interrupts
while setting up debugfs. This is what what happens when we try anyway:
|ccp 0000:03:00.2: enabling device (0000 -> 0002)
|BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:69
|in_atomic(): 1, irqs_disabled(): 1, pid: 3, name: kworker/0:0
|irq event stamp: 17150
|hardirqs last enabled at (17149): [<0000000097a18c49>] restore_regs_and_return_to_kernel+0x0/0x23
|hardirqs last disabled at (17150): [<000000000773b3a9>] _raw_write_lock_irqsave+0x1b/0x50
|softirqs last enabled at (17148): [<0000000064d56155>] __do_softirq+0x3b8/0x4c1
|softirqs last disabled at (17125): [<0000000092633c18>] irq_exit+0xb1/0xc0
|CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.16.0-rc2+ #30
|Workqueue: events work_for_cpu_fn
|Call Trace:
| dump_stack+0x7d/0xb6
| ___might_sleep+0x1eb/0x250
| down_write+0x17/0x60
| start_creating+0x4c/0xe0
| debugfs_create_dir+0x9/0x100
| ccp5_debugfs_setup+0x191/0x1b0
| ccp5_init+0x8a7/0x8c0
| ccp_dev_init+0xb8/0xe0
| sp_init+0x6c/0x90
| sp_pci_probe+0x26e/0x590
| local_pci_probe+0x3f/0x90
| work_for_cpu_fn+0x11/0x20
| process_one_work+0x1ff/0x650
| worker_thread+0x1d4/0x3a0
| kthread+0xfe/0x130
| ret_from_fork+0x27/0x50
If any locking is required, a simple mutex will do it.
Cc: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Changes since v2:
- On failure remove only the DebugFS heirarchy for this device
Changes since v1:
- Remove unneeded local variable
Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
krobot warning: make sure that all error return paths release locks.
Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Expose some data about the configuration and operation of the CCP
through debugfs entries: device name, capabilities, configuration,
statistics.
Allow the user to reset the counters to zero by writing (any value)
to the 'stats' file. This can be done per queue or per device.
Changes from V1:
- Correct polarity of test when destroying devices at module unload
Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
