mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
a384bfa32e
qemu/util
History
David Hildenbrand a384bfa32e util/oslib-posix: Support MADV_POPULATE_WRITE for os_mem_prealloc() 
Let's sense support and use it for preallocation. MADV_POPULATE_WRITE
does not require a SIGBUS handler, doesn't actually touch page content,
and avoids context switches; it is, therefore, faster and easier to handle
than our current approach.

While MADV_POPULATE_WRITE is, in general, faster than manual
prefaulting, and especially faster with 4k pages, there is still value in
prefaulting using multiple threads to speed up preallocation.

More details on MADV_POPULATE_WRITE can be found in the Linux commits
4ca9b3859dac ("mm/madvise: introduce MADV_POPULATE_(READ|WRITE) to prefault
page tables") and eb2faa513c24 ("mm/madvise: report SIGBUS as -EFAULT for
MADV_POPULATE_(READ|WRITE)"), and in the man page proposal [1].

This resolves the TODO in do_touch_pages().

In the future, we might want to look into using fallocate(), eventually
combined with MADV_POPULATE_READ, when dealing with shared file/fd
mappings and not caring about memory bindings.

[1] https://lkml.kernel.org/r/20210816081922.5155-1-david@redhat.com

Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20211217134611.31172-3-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-07 05:19:55 -05:00
..
aio-posix.c iothread: add aio-max-batch parameter 2021-07-21 13:47:50 +01:00
aio-posix.h aio-posix: remove idle poll handlers to improve scalability 2020-03-09 16:45:16 +00:00
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 avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
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 util/bufferiszero: improve avx2 accelerator 2020-04-01 14:24:03 -04:00
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 Remove the CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE switch 2020-07-13 11:40:52 +02:00
coroutine-win32.c
crc32c.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
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 util: add dbus helper unit 2020-01-06 18:41:32 +04:00
drm.c util/drm: make portable by avoiding struct dirent d_type 2020-07-13 14:36:10 +01:00
envlist.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
error.c error: make Error **errp const where it is appropriate 2019-12-18 08:36:16 +01:00
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 util/getauxval: Porting to FreeBSD getauxval feature 2020-06-26 06:45:29 -04:00
guest-random.c util/guest-random: Fix size arg to tail memcpy 2021-07-09 18:42:46 +02:00
hbitmap.c block/dirty-bitmap: improve _next_dirty_area API 2020-03-18 14:03:46 -04:00
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 linux-user: add memfd_create 2019-09-11 08:46:17 +02:00
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 xen / notify: introduce a new XenWatchList abstraction 2019-09-24 12:18:47 +01:00
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 util/oslib-posix: Support MADV_POPULATE_WRITE for os_mem_prealloc() 2022-01-07 05:19:55 -05:00
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 util/path: Do not cache all filenames at startup 2019-06-24 22:19:30 +02:00
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 yield_until_fd_readable: make it work with any AioContect 2019-10-25 14:38:29 +02:00
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 Clean up includes 2018-12-20 10:29:08 +01:00
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 Don't talk about the LGPL if the file is licensed under the GPL 2019-01-30 10:51:20 +01:00
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 tools: Fix use of fcntl(F_SETFD) during socket activation 2020-05-04 14:54:35 -05:00
thread-pool.c lockable: replaced locks with lock guard macros where appropriate 2020-05-04 16:07:43 +01:00
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 trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
transactions.c transactions: Invoke clean() after everything else 2021-11-16 09:43:44 +01:00
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 Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
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