Commit Graph

5 Commits

Author SHA1 Message Date
Stefan Hajnoczi a4a411fbaf Replace "iothread lock" with "BQL" in comments
The term "iothread lock" is obsolete. The APIs use Big QEMU Lock (BQL)
in their names. Update the code comments to use "BQL" instead of
"iothread lock".

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-id: 20240102153529.486531-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2024-01-08 10:45:43 -05:00
Stefan Hajnoczi 195801d700 system/cpus: rename qemu_mutex_lock_iothread() to bql_lock()
The Big QEMU Lock (BQL) has many names and they are confusing. The
actual QemuMutex variable is called qemu_global_mutex but it's commonly
referred to as the BQL in discussions and some code comments. The
locking APIs, however, are called qemu_mutex_lock_iothread() and
qemu_mutex_unlock_iothread().

The "iothread" name is historic and comes from when the main thread was
split into into KVM vcpu threads and the "iothread" (now called the main
loop thread). I have contributed to the confusion myself by introducing
a separate --object iothread, a separate concept unrelated to the BQL.

The "iothread" name is no longer appropriate for the BQL. Rename the
locking APIs to:
- void bql_lock(void)
- void bql_unlock(void)
- bool bql_locked(void)

There are more APIs with "iothread" in their names. Subsequent patches
will rename them. There are also comments and documentation that will be
updated in later patches.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Fabiano Rosas <farosas@suse.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Acked-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2024-01-08 10:45:43 -05:00
Vladimir Sementsov-Ogievskiy adff55b520 coverity: physmem: use simple assertions instead of modelling
Unfortunately Coverity doesn't follow the logic aroung "len" and "l"
variables in stacks finishing with flatview_{read,write}_continue() and
generate a lot of OVERRUN false-positives. When small buffer (2 or 4
bytes) is passed to mem read/write path, Coverity assumes the worst
case of sz=8 in stn_he_p()/ldn_he_p() (defined in
include/qemu/bswap.h), and reports buffer overrun.

To silence these false-positives we have model functions, which hide
real logic from Coverity.

However, it turned out that these new two assertions are enough to
quiet Coverity.

Assertions are better than hiding the logic, so let's drop the
modelling and move to assertions for memory r/w call stacks.

After patch, the sequence

 cov-make-library --output-file /tmp/master.xmldb \
    scripts/coverity-scan/model.c
 cov-build --dir ~/covtmp/master make -j9
 cov-analyze --user-model-file /tmp/master.xmldb \
    --dir ~/covtmp/master --all --strip-path "$(pwd)
 cov-format-errors --dir ~/covtmp/master \
    --html-output ~/covtmp/master_html_report

Generate for me the same big set of CIDs excepept for 6 disappeared (so
it becomes even better).

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Acked-by: David Hildenbrand <david@redhat.com>
Message-ID: <20231005140326.332830-1-vsementsov@yandex-team.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-24 12:07:47 +01:00
David Hildenbrand 022f033bd7 softmmu/physmem: Fixup qemu_ram_block_from_host() documentation
Let's fixup the documentation (e.g., removing traces of the ram_addr
parameter that no longer exists) and move it to the header file while at
it.

Message-ID: <20230926185738.277351-4-david@redhat.com>
Suggested-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
2023-10-12 14:15:21 +02:00
Philippe Mathieu-Daudé 8d7f2e767d system: Rename softmmu/ directory as system/
The softmmu/ directory contains files specific to system
emulation. Rename it as system/. Update meson rules, the
MAINTAINERS file and all the documentation and comments.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231004090629.37473-14-philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-10-08 21:08:08 +02:00