aboutsummaryrefslogtreecommitdiff
path: root/util
AgeCommit message (Collapse)Author
2020-05-18aio-posix: disable fdmon-io_uring when GSource is usedStefan Hajnoczi
The glib event loop does not call fdmon_io_uring_wait() so fd handlers waiting to be submitted build up in the list. There is no benefit is using io_uring when the glib GSource is being used, so disable it instead of implementing a more complex fix. This fixes a memory leak where AioHandlers would build up and increasing amounts of CPU time were spent iterating them in aio_pending(). The symptom is that guests become slow when QEMU is built with io_uring support. Buglink: https://bugs.launchpad.net/qemu/+bug/1877716 Fixes: 73fd282e7b6dd4e4ea1c3bbb3d302c8db51e4ccf ("aio-posix: add io_uring fd monitoring implementation") Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Tested-by: Oleksandr Natalenko <oleksandr@redhat.com> Message-id: 20200511183630.279750-3-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-05-18aio-posix: don't duplicate fd handler deletion in fdmon_io_uring_destroy()Stefan Hajnoczi
The io_uring file descriptor monitoring implementation has an internal list of fd handlers that are pending submission to io_uring. fdmon_io_uring_destroy() deletes all fd handlers on the list. Don't delete fd handlers directly in fdmon_io_uring_destroy() for two reasons: 1. This duplicates the aio-posix.c AioHandler deletion code and could become outdated if the struct changes. 2. Only handlers with the FDMON_IO_URING_REMOVE flag set are safe to remove. If the flag is not set then something still has a pointer to the fd handler. Let aio-posix.c and its user worry about that. In practice this isn't an issue because fdmon_io_uring_destroy() is only called when shutting down so all users have removed their fd handlers, but the next patch will need this! Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Tested-by: Oleksandr Natalenko <oleksandr@redhat.com> Message-id: 20200511183630.279750-2-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-05-05Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2020-05-04' into ↵Peter Maydell
staging nbd patches for 2020-05-04 - reduce client-side fragmentation of NBD trim and status requests - fix iotest 41 when run in deep tree - fix socket activation in qemu-nbd # gpg: Signature made Mon 04 May 2020 22:12:21 BST # gpg: using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A # gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full] # gpg: aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full] # gpg: aka "[jpeg image of size 6874]" [full] # Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2 F3AA A7A1 6B4A 2527 436A * remotes/ericb/tags/pull-nbd-2020-05-04: block/nbd-client: drop max_block restriction from discard block/nbd-client: drop max_block restriction from block_status iotests/041: Fix NBD socket path tools: Fix use of fcntl(F_SETFD) during socket activation Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-05-05Merge remote-tracking branch ↵Peter Maydell
'remotes/vivier2/tags/trivial-branch-for-5.1-pull-request' into staging trivial patches (20200504) Silent static analyzer warning Remove dead assignments Support -chardev serial on macOS Update MAINTAINERS Some cosmetic changes # gpg: Signature made Mon 04 May 2020 16:45:18 BST # gpg: using RSA key CD2F75DDC8E3A4DC2E4F5173F30C38BD3F2FBE3C # gpg: issuer "laurent@vivier.eu" # gpg: Good signature from "Laurent Vivier <lvivier@redhat.com>" [full] # gpg: aka "Laurent Vivier <laurent@vivier.eu>" [full] # gpg: aka "Laurent Vivier (Red Hat) <lvivier@redhat.com>" [full] # Primary key fingerprint: CD2F 75DD C8E3 A4DC 2E4F 5173 F30C 38BD 3F2F BE3C * remotes/vivier2/tags/trivial-branch-for-5.1-pull-request: hw/timer/pxa2xx_timer: Add assertion to silent static analyzer warning hw/timer/stm32f2xx_timer: Remove dead assignment hw/gpio/aspeed_gpio: Remove dead assignment hw/isa/i82378: Remove dead assignment hw/ide/sii3112: Remove dead assignment hw/input/adb-kbd: Remove dead assignment hw/i2c/pm_smbus: Remove dead assignment blockdev: Remove dead assignment block: Avoid dead assignment Compress lines for immediate return chardev: Add macOS to list of OSes that support -chardev serial MAINTAINERS: Update Keith Busch's email address elf_ops: Don't try to g_mapped_file_unref(NULL) hw/mem/pc-dimm: Fix line over 80 characters warning hw/mem/pc-dimm: Print slot number on error at pc_dimm_pre_plug() MAINTAINERS: Mark the LatticeMico32 target as orphan timer/exynos4210_mct: Remove redundant statement in exynos4210_mct_write() display/blizzard: use extract16() for fix clang analyzer warning in blizzard_draw_line16_32() scsi/esp-pci: add g_assert() for fix clang analyzer warning in esp_pci_io_write() Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-05-04tools: Fix use of fcntl(F_SETFD) during socket activationEric Blake
Blindly setting FD_CLOEXEC without a read-modify-write will inadvertently clear any other intentionally-set bits, such as a proposed new bit for designating a fd that must behave in 32-bit mode. However, we cannot use our wrapper qemu_set_cloexec(), because that wrapper intentionally abort()s on failure, whereas the probe here intentionally tolerates failure to deal with incorrect socket activation gracefully. Instead, fix the code to do the proper read-modify-write. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200420175309.75894-3-eblake@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2020-05-04lockable: replaced locks with lock guard macros where appropriateDaniel Brodsky
- ran regexp "qemu_mutex_lock\(.*\).*\n.*if" to find targets - replaced result with QEMU_LOCK_GUARD if all unlocks at function end - replaced result with WITH_QEMU_LOCK_GUARD if unlock not at end Signed-off-by: Daniel Brodsky <dnbrdsky@gmail.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-id: 20200404042108.389635-3-dnbrdsky@gmail.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-05-04Compress lines for immediate returnSimran Singhal
Compress two lines into a single line if immediate return statement is found. It also remove variables progress, val, data, ret and sock as they are no longer needed. Remove space between function "mixer_load" and '(' to fix the checkpatch.pl error:- ERROR: space prohibited between function name and open parenthesis '(' Done using following coccinelle script: @@ local idexpression ret; expression e; @@ -ret = +return e; -return ret; Signed-off-by: Simran Singhal <singhalsimran0@gmail.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20200401165314.GA3213@simran-Inspiron-5558> [lv: in handle_aiocb_write_zeroes_unmap() move "int ret" inside the #ifdef] Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-04-30qemu-option: Clean up after the previous commitMarkus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20200415083048.14339-6-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2020-04-30qobject: Eliminate qdict_iter(), use qdict_first(), qdict_next()Markus Armbruster
qdict_iter() has just three uses and no test coverage. Replace by qdict_first(), qdict_next() for more concise code and less type punning. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20200415083048.14339-5-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2020-04-29qemu-img: Move is_valid_option_list() to qemu-img.c and rewriteMarkus Armbruster
is_valid_option_list()'s purpose is ensuring qemu-img.c's can safely join multiple parameter strings separated by ',' like this: g_strdup_printf("%s,%s", params1, params2); How it does that is anything but obvious. A close reading of the code reveals that it fails exactly when its argument starts with ',' or ends with an odd number of ','. Makes sense, actually, because when the argument starts with ',', a separating ',' preceding it would get escaped, and when it ends with an odd number of ',', a separating ',' following it would get escaped. Move it to qemu-img.c and rewrite it the obvious way. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200415074927.19897-9-armbru@redhat.com>
2020-04-29qemu-option: Avoid has_help_option() in qemu_opts_parse_noisily()Markus Armbruster
When opts_parse() sets @invalidp to true, qemu_opts_parse_noisily() uses has_help_option() to decide whether to print help. This parses the input string a second time. Easy to avoid: replace @invalidp by @help_wanted. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200415074927.19897-7-armbru@redhat.com>
2020-04-29qemu-option: Fix has_help_option()'s sloppy parsingMarkus Armbruster
has_help_option() uses its own parser. It's inconsistent with qemu_opts_parse(), as demonstrated by test-qemu-opts case /qemu-opts/has_help_option. Fix by reusing the common parser. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20200415074927.19897-5-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2020-04-29qemu-option: Fix sloppy recognition of "id=..." after ",,"Markus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200415074927.19897-4-armbru@redhat.com>
2020-04-29qemu-options: Factor out get_opt_name_value() helperMarkus Armbruster
The next commits will put it to use. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200415074927.19897-3-armbru@redhat.com>
2020-04-13Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell
Bugfixes, and reworking of the atomics documentation. # gpg: Signature made Mon 13 Apr 2020 07:56:22 BST # gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83 # gpg: issuer "pbonzini@redhat.com" # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full] # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" [full] # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * remotes/bonzini/tags/for-upstream: module: increase dirs array size by one memory: Do not allow direct write access to rom_device regions vl.c: error out if -mem-path is used together with -M memory-backend rcu: do not mention atomic_mb_read/set in documentation atomics: update documentation atomics: convert to reStructuredText oslib-posix: take lock before qemu_cond_broadcast piix: fix xenfv regression, add compat machine xenfv-4.2 Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-04-13module: increase dirs array size by oneBruce Rogers
With the module upgrades code change, the statically sized dirs array can now overflow. Increase it's size by one, according to the new maximum possible usage. Fixes: bd83c861c0 ("modules: load modules from versioned /var/run dir") Signed-off-by: Bruce Rogers <brogers@suse.com> Message-Id: <20200411010746.472295-1-brogers@suse.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-11oslib-posix: take lock before qemu_cond_broadcastBauerchen
In touch_all_pages, if the mutex is not taken around qemu_cond_broadcast, qemu_cond_broadcast may be called before all touch page threads enter qemu_cond_wait. In this case, the touch page threads wait forever for the main thread to wake them up, causing a deadlock. Signed-off-by: Bauerchen <bauerchen@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-09async: use explicit memory barriersPaolo Bonzini
When using C11 atomics, non-seqcst reads and writes do not participate in the total order of seqcst operations. In util/async.c and util/aio-posix.c, in particular, the pattern that we use write ctx->notify_me write bh->scheduled read bh->scheduled read ctx->notify_me if !bh->scheduled, sleep if ctx->notify_me, notify needs to use seqcst operations for both the write and the read. In general this is something that we do not want, because there can be many sources that are polled in addition to bottom halves. The alternative is to place a seqcst memory barrier between the write and the read. This also comes with a disadvantage, in that the memory barrier is implicit on strongly-ordered architectures and it wastes a few dozen clock cycles. Fortunately, ctx->notify_me is never written concurrently by two threads, so we can assert that and relax the writes to ctx->notify_me. The resulting solution works and performs well on both aarch64 and x86. Note that the atomic_set/atomic_read combination is not an atomic read-modify-write, and therefore it is even weaker than C11 ATOMIC_RELAXED; on x86, ATOMIC_RELAXED compiles to a locked operation. Analyzed-by: Ying Fang <fangying1@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Ying Fang <fangying1@huawei.com> Message-Id: <20200407140746.8041-6-pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-04-09aio-posix: signal-proof fdmon-io_uringStefan Hajnoczi
The io_uring_enter(2) syscall returns with errno=EINTR when interrupted by a signal. Retry the syscall in this case. It's essential to do this in the io_uring_submit_and_wait() case. My interpretation of the Linux v5.5 io_uring_enter(2) code is that it shouldn't affect the io_uring_submit() case, but there is no guarantee this will always be the case. Let's check for -EINTR around both APIs. Note that the liburing APIs have -errno return values. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-id: 20200408091139.273851-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-04-07linux-user: factor out reading of /proc/self/mapsAlex Bennée
Unfortunately reading /proc/self/maps is still considered the gold standard for a process finding out about it's own memory layout. As we will want this data in other contexts soon factor out the code to read and parse the data. Rather than just blindly copying the existing sscanf based code we use a more modern glib version of the parsing code to make a more general purpose map structure. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20200403191150.863-9-alex.bennee@linaro.org>
2020-04-03aio-posix: fix test-aio /aio/event/wait with fdmon-io_uringStefan Hajnoczi
When a file descriptor becomes ready we must re-arm POLL_ADD. This is done by adding an sqe to the io_uring sq ring. The ->need_wait() function wasn't taking pending sqes into account and therefore io_uring_submit_and_wait() was not being called. Polling for cqes failed to detect fd readiness since we hadn't submitted the sqe to io_uring. This patch fixes the following tests/test-aio -p /aio/event/wait failure: ok 11 /aio/event/wait ** ERROR:tests/test-aio.c:374:test_flush_event_notifier: assertion failed: (aio_poll(ctx, false)) Reported-by: Cole Robinson <crobinso@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Tested-by: Cole Robinson <crobinso@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200402145434.99349-1-stefanha@redhat.com Fixes: 73fd282e7b6dd4e4ea1c3bbb3d302c8db51e4ccf ("aio-posix: add io_uring fd monitoring implementation") Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-04-01util/bufferiszero: improve avx2 acceleratorRobert Hoo
By increasing avx2 length_to_accel to 128, we can simplify its logic and reduce a branch. The authorship of this patch actually belongs to Richard Henderson <richard.henderson@linaro.org>, I just fixed a boundary case on his original patch. Suggested-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Robert Hoo <robert.hu@linux.intel.com> Message-Id: <1585119021-46593-2-git-send-email-robert.hu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-01util/bufferiszero: assign length_to_accel value for each accelerator caseRobert Hoo
Because in unit test, init_accel() will be called several times, each with different accelerator type. Signed-off-by: Robert Hoo <robert.hu@linux.intel.com> Message-Id: <1585119021-46593-1-git-send-email-robert.hu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-23aio-posix: fix io_uring with external eventsStefan Hajnoczi
When external event sources are disabled fdmon-io_uring falls back to fdmon-poll. The ->need_wait() callback needs to watch for this so it can return true when external event sources are disabled. It is also necessary to call ->wait() when AioHandlers have changed because io_uring is asynchronous and we must submit new sqes. Both of these changes to ->need_wait() together fix tests/test-aio -p /aio/external-client, which failed with: test-aio: tests/test-aio.c:404: test_aio_external_client: Assertion `aio_poll(ctx, false)' failed. Reported-by: Julia Suvorova <jusual@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Message-id: 20200319163559.117903-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-03-18block/dirty-bitmap: improve _next_dirty_area APIVladimir Sementsov-Ogievskiy
Firstly, _next_dirty_area is for scenarios when we may contiguously search for next dirty area inside some limited region, so it is more comfortable to specify "end" which should not be recalculated on each iteration. Secondly, let's add a possibility to limit resulting area size, not limiting searching area. This will be used in NBD code in further commit. (Note that now bdrv_dirty_bitmap_next_dirty_area is unused) Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20200205112041.6003-8-vsementsov@virtuozzo.com Signed-off-by: John Snow <jsnow@redhat.com>
2020-03-18block/dirty-bitmap: add _next_dirty APIVladimir Sementsov-Ogievskiy
We have bdrv_dirty_bitmap_next_zero, let's add corresponding bdrv_dirty_bitmap_next_dirty, which is more comfortable to use than bitmap iterators in some cases. For test modify test_hbitmap_next_zero_check_range to check both next_zero and next_dirty and add some new checks. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20200205112041.6003-7-vsementsov@virtuozzo.com Signed-off-by: John Snow <jsnow@redhat.com>
2020-03-18block/dirty-bitmap: switch _next_dirty_area and _next_zero to int64_tVladimir Sementsov-Ogievskiy
We are going to introduce bdrv_dirty_bitmap_next_dirty so that same variable may be used to store its return value and to be its parameter, so it would int64_t. Similarly, we are going to refactor hbitmap_next_dirty_area to use hbitmap_next_dirty together with hbitmap_next_zero, therefore we want hbitmap_next_zero parameter type to be int64_t too. So, for convenience update all parameters of *_next_zero and *_next_dirty_area to be int64_t. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20200205112041.6003-6-vsementsov@virtuozzo.com Signed-off-by: John Snow <jsnow@redhat.com>
2020-03-18hbitmap: drop meta bitmaps as they are unusedVladimir Sementsov-Ogievskiy
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20200205112041.6003-5-vsementsov@virtuozzo.com Signed-off-by: John Snow <jsnow@redhat.com>
2020-03-18hbitmap: unpublish hbitmap_iter_skip_wordsVladimir Sementsov-Ogievskiy
Function is internal and even commented as internal. Drop its definition from .h file. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20200205112041.6003-4-vsementsov@virtuozzo.com Signed-off-by: John Snow <jsnow@redhat.com>
2020-03-18hbitmap: move hbitmap_iter_next_word to hbitmap.cVladimir Sementsov-Ogievskiy
The function is definitely internal (it's not used by third party and it has complicated interface). Move it to .c file. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20200205112041.6003-3-vsementsov@virtuozzo.com Signed-off-by: John Snow <jsnow@redhat.com>
2020-03-18hbitmap: assert that we don't create bitmap larger than INT64_MAXVladimir Sementsov-Ogievskiy
We have APIs which returns signed int64_t, to be able to return error. Therefore we can't handle bitmaps with absolute size larger than (INT64_MAX+1). Still, keep maximum to be INT64_MAX which is a bit safer. Note, that bitmaps are used to represent disk images, which can't exceed INT64_MAX anyway. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20200205112041.6003-2-vsementsov@virtuozzo.com Signed-off-by: John Snow <jsnow@redhat.com>
2020-03-17lockable: add lock guardsStefan Hajnoczi
This patch introduces two lock guard macros that automatically unlock a lock object (QemuMutex and others): void f(void) { QEMU_LOCK_GUARD(&mutex); if (!may_fail()) { return; /* automatically unlocks mutex */ } ... } and: WITH_QEMU_LOCK_GUARD(&mutex) { if (!may_fail()) { return; /* automatically unlocks mutex */ } } /* automatically unlocks mutex here */ ... Convert qemu-timer.c functions that benefit from these macros as an example. Manual qemu_mutex_lock/unlock() callers are left unmodified in cases where clarity would not improve by switching to the macros. Many other QemuMutex users remain in the codebase that might benefit from lock guards. Over time they can be converted, if that is desirable. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> [Use QEMU_MAKE_LOCKABLE_NONNULL. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16modules: load modules from versioned /var/run dirChristian Ehrhardt
On upgrades the old .so files usually are replaced. But on the other hand since a qemu process represents a guest instance it is usually kept around. That makes late addition of dynamic features e.g. 'hot-attach of a ceph disk' fail by trying to load a new version of e.f. block-rbd.so into an old still running qemu binary. This adds a fallback to also load modules from a versioned directory in the temporary /var/run path. That way qemu is providing a way for packaging to store modules of an upgraded qemu package as needed until the next reboot. An example how that can then be used in packaging can be seen in: https://git.launchpad.net/~paelzer/ubuntu/+source/qemu/log/?h=bug-1847361-miss-old-so-on-upgrade-UBUNTU Fixes: https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1847361 Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20200310145806.18335-2-christian.ehrhardt@canonical.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16oslib-posix: initialize mutex and condition variablePaolo Bonzini
The mutex and condition variable were never initialized, causing -mem-prealloc to abort with an assertion failure. Fixes: 037fb5eb3941c80a2b7c36a843e47207ddb004d4 Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com> Cc: bauerchen <bauerchen@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16util: add util function buffer_zero_avx512()Robert Hoo
And intialize buffer_is_zero() with it, when Intel AVX512F is available on host. This function utilizes Intel AVX512 fundamental instructions which is faster than its implementation with AVX2 (in my unit test, with 4K buffer, on CascadeLake SP, ~36% faster, buffer_zero_avx512() V.S. buffer_zero_avx2()). Signed-off-by: Robert Hoo <robert.hu@linux.intel.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-11Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into ↵Peter Maydell
staging Pull request # gpg: Signature made Wed 11 Mar 2020 12:40:36 GMT # gpg: using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8 # gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full] # gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" [full] # Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8 * remotes/stefanha/tags/block-pull-request: aio-posix: remove idle poll handlers to improve scalability aio-posix: support userspace polling of fd monitoring aio-posix: add io_uring fd monitoring implementation aio-posix: simplify FDMonOps->update() prototype aio-posix: extract ppoll(2) and epoll(7) fd monitoring aio-posix: move RCU_READ_LOCK() into run_poll_handlers() aio-posix: completely stop polling when disabled aio-posix: remove confusing QLIST_SAFE_REMOVE() qemu/queue.h: clear linked list pointers on remove Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-03-09aio-posix: remove idle poll handlers to improve scalabilityStefan Hajnoczi
When there are many poll handlers it's likely that some of them are idle most of the time. Remove handlers that haven't had activity recently so that the polling loop scales better for guests with a large number of devices. This feature only takes effect for the Linux io_uring fd monitoring implementation because it is capable of combining fd monitoring with userspace polling. The other implementations can't do that and risk starving fds in favor of poll handlers, so don't try this optimization when they are in use. IOPS improves from 10k to 105k when the guest has 100 virtio-blk-pci,num-queues=32 devices and 1 virtio-blk-pci,num-queues=1 device for rw=randread,iodepth=1,bs=4k,ioengine=libaio on NVMe. [Clarified aio_poll_handlers locking discipline explanation in comment after discussion with Paolo Bonzini <pbonzini@redhat.com>. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200305170806.1313245-8-stefanha@redhat.com Message-Id: <20200305170806.1313245-8-stefanha@redhat.com>
2020-03-09aio-posix: support userspace polling of fd monitoringStefan Hajnoczi
Unlike ppoll(2) and epoll(7), Linux io_uring completions can be polled from userspace. Previously userspace polling was only allowed when all AioHandler's had an ->io_poll() callback. This prevented starvation of fds by userspace pollable handlers. Add the FDMonOps->need_wait() callback that enables userspace polling even when some AioHandlers lack ->io_poll(). For example, it's now possible to do userspace polling when a TCP/IP socket is monitored thanks to Linux io_uring. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200305170806.1313245-7-stefanha@redhat.com Message-Id: <20200305170806.1313245-7-stefanha@redhat.com>
2020-03-09aio-posix: add io_uring fd monitoring implementationStefan Hajnoczi
The recent Linux io_uring API has several advantages over ppoll(2) and epoll(2). Details are given in the source code. Add an io_uring implementation and make it the default on Linux. Performance is the same as with epoll(7) but later patches add optimizations that take advantage of io_uring. It is necessary to change how aio_set_fd_handler() deals with deleting AioHandlers since removing monitored file descriptors is asynchronous in io_uring. fdmon_io_uring_remove() marks the AioHandler deleted and aio_set_fd_handler() will let it handle deletion in that case. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200305170806.1313245-6-stefanha@redhat.com Message-Id: <20200305170806.1313245-6-stefanha@redhat.com>
2020-03-09aio-posix: simplify FDMonOps->update() prototypeStefan Hajnoczi
The AioHandler *node, bool is_new arguments are more complicated to think about than simply being given AioHandler *old_node, AioHandler *new_node. Furthermore, the new Linux io_uring file descriptor monitoring mechanism added by the new patch requires access to both the old and the new nodes. Make this change now in preparation. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200305170806.1313245-5-stefanha@redhat.com Message-Id: <20200305170806.1313245-5-stefanha@redhat.com>
2020-03-09aio-posix: extract ppoll(2) and epoll(7) fd monitoringStefan Hajnoczi
The ppoll(2) and epoll(7) file descriptor monitoring implementations are mixed with the core util/aio-posix.c code. Before adding another implementation for Linux io_uring, extract out the existing ones so there is a clear interface and the core code is simpler. The new interface is AioContext->fdmon_ops, a pointer to a FDMonOps struct. See the patch for details. Semantic changes: 1. ppoll(2) now reflects events from pollfds[] back into AioHandlers while we're still on the clock for adaptive polling. This was already happening for epoll(7), so if it's really an issue then we'll need to fix both in the future. 2. epoll(7)'s fallback to ppoll(2) while external events are disabled was broken when the number of fds exceeded the epoll(7) upgrade threshold. I guess this code path simply wasn't tested and no one noticed the bug. I didn't go out of my way to fix it but the correct code is simpler than preserving the bug. I also took some liberties in removing the unnecessary AioContext->epoll_available (just check AioContext->epollfd != -1 instead) and AioContext->epoll_enabled (it's implicit if our AioContext->fdmon_ops callbacks are being invoked) fields. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200305170806.1313245-4-stefanha@redhat.com Message-Id: <20200305170806.1313245-4-stefanha@redhat.com>
2020-03-09aio-posix: move RCU_READ_LOCK() into run_poll_handlers()Stefan Hajnoczi
Now that run_poll_handlers_once() is only called by run_poll_handlers() we can improve the CPU time profile by moving the expensive RCU_READ_LOCK() out of the polling loop. This reduces the run_poll_handlers() from 40% CPU to 10% CPU in perf's sampling profiler output. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200305170806.1313245-3-stefanha@redhat.com Message-Id: <20200305170806.1313245-3-stefanha@redhat.com>
2020-03-09aio-posix: completely stop polling when disabledStefan Hajnoczi
One iteration of polling is always performed even when polling is disabled. This is done because: 1. Userspace polling is cheaper than making a syscall. We might get lucky. 2. We must poll once more after polling has stopped in case an event occurred while stopping polling. However, there are downsides: 1. Polling becomes a bottleneck when the number of event sources is very high. It's more efficient to monitor fds in that case. 2. A high-frequency polling event source can starve non-polling event sources because ppoll(2)/epoll(7) is never invoked. This patch removes the forced polling iteration so that poll_ns=0 really means no polling. IOPS increases from 10k to 60k when the guest has 100 virtio-blk-pci,num-queues=32 devices and 1 virtio-blk-pci,num-queues=1 device because the large number of event sources being polled slows down the event loop. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200305170806.1313245-2-stefanha@redhat.com Message-Id: <20200305170806.1313245-2-stefanha@redhat.com>
2020-03-09aio-posix: remove confusing QLIST_SAFE_REMOVE()Stefan Hajnoczi
QLIST_SAFE_REMOVE() is confusing here because the node must be on the list. We actually just wanted to clear the linked list pointers when removing it from the list. QLIST_REMOVE() now does this, so switch to it. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200224103406.1894923-3-stefanha@redhat.com Message-Id: <20200224103406.1894923-3-stefanha@redhat.com>
2020-03-09util/osdep: Improve error report by calling error_setg_win32()Philippe Mathieu-Daudé
Use error_setg_win32() which adds a hint similar to strerror(errno)). Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20200228100726.8414-3-philmd@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-02-25mem-prealloc: optimize large guest startupbauerchen
[desc]: Large memory VM starts slowly when using -mem-prealloc, and there are some areas to optimize in current method; 1、mmap will be used to alloc threads stack during create page clearing threads, and it will attempt mm->mmap_sem for write lock, but clearing threads have hold read lock, this competition will cause threads createion very slow; 2、methods of calcuating pages for per threads is not well;if we use 64 threads to split 160 hugepage,63 threads clear 2page,1 thread clear 34 page,so the entire speed is very slow; to solve the first problem,we add a mutex in thread function,and start all threads when all threads finished createion; and the second problem, we spread remainder to other threads,in situation that 160 hugepage and 64 threads, there are 32 threads clear 3 pages,and 32 threads clear 2 pages. [test]: 320G 84c VM start time can be reduced to 10s 680G 84c VM start time can be reduced to 18s Signed-off-by: bauerchen <bauerchen@tencent.com> Reviewed-by: Pan Rui <ruippan@tencent.com> Reviewed-by: Ivan Ren <ivanren@tencent.com> [Simplify computation of the number of pages per thread. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-22module: check module wasn't already initializedAlexander Bulekov
The virtual-device fuzzer must initialize QOM, prior to running vl:qemu_init, so that it can use the qos_graph to identify the arguments required to initialize a guest for libqos-assisted fuzzing. This change prevents errors when vl:qemu_init tries to (re)initialize the previously initialized QOM module. Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-id: 20200220041118.23264-4-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22aio-posix: make AioHandler dispatch O(1) with epollStefan Hajnoczi
File descriptor monitoring is O(1) with epoll(7), but aio_dispatch_handlers() still scans all AioHandlers instead of dispatching just those that are ready. This makes aio_poll() O(n) with respect to the total number of registered handlers. Add a local ready_list to aio_poll() so that each nested aio_poll() builds a list of handlers ready to be dispatched. Since file descriptor polling is level-triggered, nested aio_poll() calls also see fds that were ready in the parent but not yet dispatched. This guarantees that nested aio_poll() invocations will dispatch all fds, even those that became ready before the nested invocation. Since only handlers ready to be dispatched are placed onto the ready_list, the new aio_dispatch_ready_handlers() function provides O(1) dispatch. Note that AioContext polling is still O(n) and currently cannot be fully disabled. This still needs to be fixed before aio_poll() is fully O(1). Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Message-id: 20200214171712.541358-6-stefanha@redhat.com [Fix compilation error on macOS where there is no epoll(87). The aio_epoll() prototype was out of date and aio_add_ready_list() needed to be moved outside the ifdef. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22aio-posix: make AioHandler deletion O(1)Stefan Hajnoczi
It is not necessary to scan all AioHandlers for deletion. Keep a list of deleted handlers instead of scanning the full list of all handlers. The AioHandler->deleted field can be dropped. Let's check if the handler has been inserted into the deleted list instead. Add a new QLIST_IS_INSERTED() API for this check. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Message-id: 20200214171712.541358-5-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22aio-posix: don't pass ns timeout to epoll_wait()Stefan Hajnoczi
Don't pass the nanosecond timeout into epoll_wait(), which expects milliseconds. The epoll_wait() timeout value does not matter if qemu_poll_ns() determined that the poll fd is ready, but passing a value in the wrong units is still ugly. Pass a 0 timeout to epoll_wait() instead. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Message-id: 20200214171712.541358-3-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>