qemu-e2k/util
Greg Kurz ef149763a8 rcu: Introduce force_rcu notifier
The drain_rcu_call() function can be blocked as long as an RCU reader
stays in a read-side critical section. This is typically what happens
when a TCG vCPU is executing a busy loop. It can deadlock the QEMU
monitor as reported in https://gitlab.com/qemu-project/qemu/-/issues/650 .

This can be avoided by allowing drain_rcu_call() to enforce an RCU grace
period. Since each reader might need to do specific actions to end a
read-side critical section, do it with notifiers.

Prepare ground for this by adding a notifier list to the RCU reader
struct and use it in wait_for_readers() if drain_rcu_call() is in
progress. An API is added for readers to register their notifiers.

This is largely based on a draft from Paolo Bonzini.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211109183523.47726-2-groug@kaod.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-10 13:20:15 +01:00
..
aio-posix.c iothread: add aio-max-batch parameter 2021-07-21 13:47:50 +01:00
aio-posix.h
aio-wait.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
aio-win32.c iothread: add aio-max-batch parameter 2021-07-21 13:47:50 +01:00
aiocb.c
async.c iothread: add aio-max-batch parameter 2021-07-21 13:47:50 +01:00
atomic64.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
base64.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
bitmap.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
bitops.c
block-helpers.c block: move logical block size check function to a common utility function 2020-10-23 13:42:16 +01:00
block-helpers.h block: move logical block size check function to a common utility function 2020-10-23 13:42:16 +01:00
buffer.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
bufferiszero.c
cacheflush.c util/cacheflush: Fix error generated by clang 2021-01-21 13:00:41 +01:00
cacheinfo.c util: Enhance flush_icache_range with separate data pointer 2021-01-07 05:09:41 -10:00
compatfd.c util/compatfd.c: use libc signalfd wrapper instead of raw syscall 2021-10-13 10:47:49 +02:00
coroutine-sigaltstack.c coroutine-sigaltstack: Add SIGUSR2 mutex 2021-01-26 14:36:37 +01:00
coroutine-ucontext.c
coroutine-win32.c
crc32c.c
crc-ccitt.c util: Add CRC16 (CCITT) calculation routines 2021-01-24 20:10:54 +01:00
cutils.c cutils: fix memory leak in get_relocated_path() 2021-05-13 18:06:40 +02:00
dbus.c
drm.c
envlist.c
error.c
event_notifier-posix.c event_notifier: Set ->initialized earlier in event_notifier_init() 2021-02-16 17:15:39 +01:00
event_notifier-win32.c
fdmon-epoll.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
fdmon-io_uring.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
fdmon-poll.c fdmon-poll: reset npfd when upgrading to fdmon-epoll 2020-09-23 13:45:52 +01:00
fifo8.c utils/fifo8: change fatal errors from abort() to assert() 2021-02-07 20:38:20 +00:00
filemonitor-inotify.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
filemonitor-stub.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
getauxval.c
guest-random.c util/guest-random: Fix size arg to tail memcpy 2021-07-09 18:42:46 +02:00
hbitmap.c
hexdump.c util/hexdump: introduce qemu_hexdump_line() 2020-09-29 02:14:30 -04:00
host-utils.c host-utils: add 128-bit quotient support to divu128/divs128 2021-10-27 17:10:00 -07:00
id.c net: Use id_generate() in the network subsystem, too 2021-03-09 21:47:45 +01:00
iov.c util/iov: make qemu_iovec_init_extended() honest 2021-02-03 08:00:33 -06:00
iova-tree.c util: Make some iova_tree parameters const 2021-11-02 15:57:21 +01:00
keyval.c keyval: introduce keyval_parse_into 2021-07-06 08:33:51 +02:00
lockcnt.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
log.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
main-loop.c util/async: add a human-readable name to BHs for debugging 2021-07-05 11:40:32 +01:00
memfd.c
meson.build configure, meson: move more compiler checks to Meson 2021-10-14 09:50:57 +02:00
mmap-alloc.c Deprecate pmem=on with non-DAX capable backend file 2021-07-06 18:05:16 -04:00
module.c modules: check arch on qom lookup 2021-07-09 18:20:27 +02:00
notify.c
nvdimm-utils.c Clean up includes 2020-12-10 17:16:44 +01:00
osdep.c util/osdep: Add qemu_mprotect_rw 2021-06-13 17:42:40 -07:00
oslib-posix.c memory: Introduce RAM_NORESERVE and wire it up in qemu_ram_mmap() 2021-06-15 20:27:38 +02:00
oslib-win32.c util/oslib-win32: Fix fatal assertion in qemu_try_memalign 2021-06-19 14:51:51 -07:00
pagesize.c
path.c
qdist.c
qemu-co-shared-resource.c co-shared-resource: protect with a mutex 2021-06-25 14:24:24 +03:00
qemu-config.c qemu-config: restore "machine" in qmp_query_command_line_options() 2021-07-22 14:44:47 +02:00
qemu-coroutine-io.c
qemu-coroutine-lock.c coroutine-lock: Reimplement CoRwlock to fix downgrade bug 2021-03-31 10:44:21 +01:00
qemu-coroutine-sleep.c coroutine-sleep: introduce qemu_co_sleep 2021-05-21 18:22:33 +01:00
qemu-coroutine.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
qemu-error.c error: rename error_with_timestamp to message_with_timestamp 2021-02-01 10:50:55 +00:00
qemu-openpty.c util: Remove redundant checks in the openpty() 2021-09-15 14:42:48 +02:00
qemu-option.c qemu-option: Allow deleting opts during qemu_opts_foreach() 2021-10-15 16:11:22 +02:00
qemu-print.c monitor: Use getter/setter functions for cur_mon 2020-10-09 07:08:19 +02:00
qemu-progress.c util/: fix some comment spelling errors 2020-09-17 20:38:42 +02:00
qemu-sockets.c build-sys: add HAVE_IPPROTO_MPTCP 2021-09-30 15:30:25 +02:00
qemu-thread-common.h
qemu-thread-posix.c configure, meson: move pthread_setname_np checks to Meson 2021-10-14 09:50:57 +02:00
qemu-thread-win32.c util: Pass file+line to qemu_rec_mutex_unlock_impl 2021-06-16 15:03:26 +02:00
qemu-timer-common.c semihosting: Implement SYS_ELAPSED and SYS_TICKFREQ 2021-01-18 10:05:06 +00:00
qemu-timer.c spapr: rollback 'unplug timeout' for CPU hotunplugs 2021-04-12 12:27:14 +10:00
qht.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
qsp.c qemu/atomic: Add aligned_{int64,uint64}_t types 2021-07-21 07:45:38 -10:00
range.c
rcu.c rcu: Introduce force_rcu notifier 2021-11-10 13:20:15 +01:00
readline.c readline: Fix possible array index out of bounds in readline_hist_add() 2021-01-04 11:13:39 +00:00
selfmap.c util/selfmap: Discard mapping on error 2021-07-26 07:06:49 -10:00
stats64.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
sys_membarrier.c
systemd.c
thread-pool.c
throttle.c Remove superfluous timer_del() calls 2021-01-08 15:13:38 +00:00
timed-average.c
trace-events modules: add tracepoints 2021-07-09 18:20:27 +02:00
trace.h
transactions.c util: add transactions.c 2021-04-30 12:27:47 +02:00
unicode.c
uri.c util/uri: do not check argument of uri_free() 2021-07-09 12:26:05 +02:00
userfaultfd.c migration: introduce UFFD-WP low-level interface helpers 2021-02-08 11:19:51 +00:00
uuid.c
vfio-helpers.c util/vfio-helpers: Let qemu_vfio_do_mapping() propagate Error 2021-09-07 09:08:24 +01:00
vhost-user-server.c util/vhost-user-server: move header to include/ 2020-10-23 13:42:16 +01:00
yank.c yank: Remove dependency on qiochannel 2021-04-01 15:27:44 +04:00