linux/samples
David Howells f5b5a164f9 Add sample notification program
The sample program is run like:

	./samples/watch_queue/watch_test

and watches "/" for mount changes and the current session keyring for key
changes:

	# keyctl add user a a @s
	1035096409
	# keyctl unlink 1035096409 @s

producing:

	# ./watch_test
	read() = 16
	NOTIFY[000]: ty=000001 sy=02 i=00000110
	KEY 2ffc2e5d change=2[linked] aux=1035096409
	read() = 16
	NOTIFY[000]: ty=000001 sy=02 i=00000110
	KEY 2ffc2e5d change=3[unlinked] aux=1035096409

Other events may be produced, such as with a failing disk:

	read() = 22
	NOTIFY[000]: ty=000003 sy=02 i=00000416
	USB 3-7.7 dev-reset e=0 r=0
	read() = 24
	NOTIFY[000]: ty=000002 sy=06 i=00000418
	BLOCK 00800050 e=6[critical medium] s=64000ef8

This corresponds to:

	blk_update_request: critical medium error, dev sdf, sector 1677725432 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0

in dmesg.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-19 15:38:07 +01:00
..
auxdisplay .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
binderfs treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
bpf samples: bpf: Fix build error 2020-05-14 12:37:39 -07:00
configfs treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 145 2019-05-30 11:25:18 -07:00
connector .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
ftrace tracing: Sample module to demonstrate kernel access to Ftrace instances. 2019-11-22 19:41:08 -05:00
hidraw .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
hw_breakpoint samples/hw_breakpoint: drop use of kallsyms_lookup_name() 2020-04-07 10:43:44 -07:00
kdb treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
kfifo proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
kobject treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
kprobes treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
livepatch livepatch: Handle allocation failure in the sample of shadow variable API 2020-01-17 11:12:06 +01:00
mei .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
mic/mpssd .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
pidfd .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
pktgen samples: pktgen: allow to specify destination IP range (CIDR) 2019-10-07 09:26:32 -04:00
qmi treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
rpmsg samples/rpmsg: Introduce a module parameter for message count 2019-08-26 22:10:39 -07:00
seccomp .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
timers .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
trace_events tracing: Fix doc mistakes in trace sample 2020-05-07 13:32:57 -04:00
trace_printk samples/trace_printk: Wait for IRQ work to finish 2019-12-21 16:08:22 -05:00
uhid kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
v4l media: rename VFL_TYPE_GRABBER to _VIDEO 2020-02-24 16:52:39 +01:00
vfio-mdev vmalloc: fix remap_vmalloc_range() bounds checks 2020-04-21 11:11:56 -07:00
vfs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
watch_queue Add sample notification program 2020-05-19 15:38:07 +01:00
watchdog .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
Kconfig Add sample notification program 2020-05-19 15:38:07 +01:00
Makefile Add sample notification program 2020-05-19 15:38:07 +01:00