linux/kernel
John Fastabend ffa3566001 sockmap: convert refcnt to an atomic refcnt
The sockmap refcnt up until now has been wrapped in the
sk_callback_lock(). So its not actually needed any locking of its
own. The counter itself tracks the lifetime of the psock object.
Sockets in a sockmap have a lifetime that is independent of the
map they are part of. This is possible because a single socket may
be in multiple maps. When this happens we can only release the
psock data associated with the socket when the refcnt reaches
zero. There are three possible delete sock reference decrement
paths first through the normal sockmap process, the user deletes
the socket from the map. Second the map is removed and all sockets
in the map are removed, delete path is similar to case 1. The third
case is an asyncronous socket event such as a closing the socket. The
last case handles removing sockets that are no longer available.
For completeness, although inc does not pose any problems in this
patch series, the inc case only happens when a psock is added to a
map.

Next we plan to add another socket prog type to handle policy and
monitoring on the TX path. When we do this however we will need to
keep a reference count open across the sendmsg/sendpage call and
holding the sk_callback_lock() here (on every send) seems less than
ideal, also it may sleep in cases where we hit memory pressure.
Instead of dealing with these issues in some clever way simply make
the reference counting a refcnt_t type and do proper atomic ops.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-19 21:14:38 +01:00
..
bpf sockmap: convert refcnt to an atomic refcnt 2018-03-19 21:14:38 +01:00
cgroup kernel/cpuset: current_cpuset_is_being_rebound can be boolean 2018-02-06 18:32:47 -08:00
configs KVM changes for 4.16 2018-02-10 13:16:35 -08:00
debug signal: Simplify and fix kdb_send_sig 2018-01-03 18:01:08 -06:00
events vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
gcov License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq genirq/matrix: Handle CPU offlining proper 2018-02-22 22:05:43 +01:00
livepatch Merge branch 'for-4.16/remove-immediate' into for-linus 2018-01-31 16:36:38 +01:00
locking locking/qspinlock: Ensure node->count is updated before initialising node 2018-02-13 14:50:14 +01:00
power x86/power: Fix swsusp_arch_resume prototype 2018-02-02 23:33:50 +01:00
printk Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2018-03-01 10:06:39 -08:00
rcu SCSI misc on 20180131 2018-01-31 11:23:28 -08:00
sched sched/cpufreq: Remove unused SUGOV_KTHREAD_PRIORITY macro 2018-02-13 13:04:03 +01:00
time timers: Forward timer base before migrating timers 2018-02-28 23:34:33 +01:00
trace bpf: add support to read sample address in bpf program 2018-03-08 02:22:34 +01:00
.gitignore
acct.c kernel/acct.c: fix the acct->needcheck check in check_free_space() 2018-01-04 16:45:09 -08:00
async.c kernel/async.c: revert "async: simplify lowest_in_progress()" 2018-02-06 18:32:44 -08:00
audit_fsnotify.c
audit_tree.c Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2017-11-14 14:08:20 -08:00
audit_watch.c audit/stable-4.13 PR 20170816 2017-08-16 16:48:34 -07:00
audit.c net: Convert audit_net_ops 2018-02-13 10:36:06 -05:00
audit.h audit/stable-4.15 PR 20171113 2017-11-15 13:28:48 -08:00
auditfilter.c audit: filter PATH records keyed on filesystem magic 2017-11-10 16:08:56 -05:00
auditsc.c audit/stable-4.15 PR 20171113 2017-11-15 13:28:48 -08:00
backtracetest.c
bounds.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
capability.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compat.c cpumask: make cpumask_size() return "unsigned int" 2018-02-06 18:32:45 -08:00
configs.c
context_tracking.c
cpu_pm.c PM / CPU: replace raw_notifier with atomic_notifier 2017-07-31 13:09:49 +02:00
cpu.c Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-12-31 12:30:34 -08:00
crash_core.c kdump: write correct address of mem_section into vmcoreinfo 2018-01-13 10:42:48 -08:00
crash_dump.c
cred.c
delayacct.c delayacct: Account blkio completion on the correct task 2018-01-16 03:29:36 +01:00
dma.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
elfcore.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
exec_domain.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
exit.c kernel/exit.c: export abort() to modules 2018-01-04 16:45:09 -08:00
extable.c extable: Make init_kernel_text() global 2018-02-21 16:54:06 +01:00
fail_function.c error-injection: Support fault injection framework 2018-01-12 17:33:38 -08:00
fork.c include/linux/sched/mm.h: re-inline mmdrop() 2018-02-21 15:35:42 -08:00
freezer.c
futex_compat.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
futex.c pids: introduce find_get_task_by_vpid() helper 2018-02-06 18:32:46 -08:00
groups.c kernel: make groups_sort calling a responsibility group_info allocators 2017-12-14 16:00:49 -08:00
hung_task.c
irq_work.c irq/work: Improve the flag definitions 2018-01-08 19:43:15 +01:00
jump_label.c extable: Make init_kernel_text() global 2018-02-21 16:54:06 +01:00
kallsyms.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2018-02-01 13:36:15 -08:00
kcmp.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c kcov: detect double association with a single task 2018-02-06 18:32:46 -08:00
kexec_core.c x86/mm, kexec: Allow kexec to be used with SME 2017-07-18 11:38:04 +02:00
kexec_file.c resource: Provide resource struct in resource walk callback 2017-11-07 15:35:57 +01:00
kexec_internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
kexec.c kdump: protect vmcoreinfo data under the crash memory 2017-07-12 16:26:00 -07:00
kmod.c kmod: move #ifdef CONFIG_MODULES wrapper to Makefile 2017-09-08 18:26:51 -07:00
kprobes.c kprobes: Propagate error from disarm_kprobe_ftrace() 2018-02-16 09:12:58 +01:00
ksysfs.c kexec: move vmcoreinfo out of the kernel's .bss section 2017-07-12 16:25:59 -07:00
kthread.c treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
latencytop.c
Makefile error-injection: Support fault injection framework 2018-01-12 17:33:38 -08:00
memremap.c memremap: fix softlockup reports at teardown 2018-03-02 19:34:50 -08:00
module_signing.c
module-internal.h
module.c Modules updates for v4.16 2018-02-07 14:29:34 -08:00
notifier.c
nsproxy.c
padata.c padata: add SPDX identifier 2018-01-05 18:43:00 +11:00
panic.c kernel/panic.c: add TAINT_AUX 2017-11-17 16:10:04 -08:00
params.c kernel/params.c: improve STANDARD_PARAM_DEF readability 2017-10-03 17:54:26 -07:00
pid_namespace.c pid: remove pidhash 2017-11-17 16:10:04 -08:00
pid.c pids: introduce find_get_task_by_vpid() helper 2018-02-06 18:32:46 -08:00
profile.c
ptrace.c pids: introduce find_get_task_by_vpid() helper 2018-02-06 18:32:46 -08:00
range.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
reboot.c kernel/reboot.c: add devm_register_reboot_notifier() 2017-11-17 16:10:04 -08:00
relay.c kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE 2018-02-21 15:35:43 -08:00
resource.c Merge branch 'akpm' (patches from Andrew) 2018-02-06 22:15:42 -08:00
seccomp.c - Fix seccomp GET_METADATA to deal with field sizes correctly (Tycho Andersen) 2018-02-22 10:50:24 -08:00
signal.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching 2018-01-31 13:02:18 -08:00
smp.c smp/core: Use lockdep to assert IRQs are disabled/enabled 2017-11-08 11:13:50 +01:00
smpboot.c watchdog/core, powerpc: Lock cpus across reconfiguration 2017-10-04 10:53:54 +02:00
smpboot.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
softirq.c softirq: Eliminate cond_resched_rcu_qs() in favor of cond_resched() 2017-12-04 10:28:58 -08:00
stacktrace.c
stop_machine.c
sys_ni.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sys.c fix typo in assignment of fs default overflow gid 2017-12-14 16:01:45 -06:00
sysctl_binary.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sysctl.c pipe: reject F_SETPIPE_SZ with size over UINT_MAX 2018-02-06 18:32:47 -08:00
task_work.c locking/barriers: Convert users of lockless_dereference() to READ_ONCE() 2017-12-17 13:57:15 +01:00
taskstats.c pids: introduce find_get_task_by_vpid() helper 2018-02-06 18:32:46 -08:00
test_kprobes.c kprobes: Disable the jprobes test code 2017-10-20 11:02:54 +02:00
torture.c torture: Save a line in stutter_wait(): while -> for 2017-12-11 09:18:30 -08:00
tracepoint.c tracepoint: Remove smp_read_barrier_depends() from comment 2017-12-04 10:52:56 -08:00
tsacct.c
ucount.c
uid16.c kernel: make groups_sort calling a responsibility group_info allocators 2017-12-14 16:00:49 -08:00
umh.c kernel/umh.c: optimize 'proc_cap_handler()' 2017-11-17 16:10:01 -08:00
up.c smp: Avoid using two cache lines for struct call_single_data 2017-08-29 15:14:38 +02:00
user_namespace.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-11-16 12:20:15 -08:00
user-return-notifier.c
user.c efivarfs: Limit the rate for non-root to read files 2018-02-22 10:21:02 -08:00
utsname_sysctl.c
utsname.c
watchdog_hld.c Merge branch 'linus' into core/urgent, to pick up dependent commits 2017-11-04 08:53:04 +01:00
watchdog.c Merge branch 'linus' into sched/core, to pick up fixes 2017-11-08 10:17:15 +01:00
workqueue_internal.h Merge branch 'for-4.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2017-11-06 12:26:49 -08:00
workqueue.c Fixes for 4.16. I contains fixes for deadlock on runtime suspend on few 2018-02-22 08:39:26 +10:00