b27211db61
A proposed update to clang's -Wconstant-logical-operand to warn when the
left hand side is a constant shows the following instance in
nsecs_to_jiffies_timeout() when NSEC_PER_SEC is not a multiple of HZ,
such as CONFIG_HZ=300:
In file included from drivers/gpu/drm/v3d/v3d_debugfs.c:12:
drivers/gpu/drm/v3d/v3d_drv.h:343:24: warning: use of logical '&&' with constant operand [-Wconstant-logical-operand]
343 | if (NSEC_PER_SEC % HZ &&
| ~~~~~~~~~~~~~~~~~ ^
drivers/gpu/drm/v3d/v3d_drv.h:343:24: note: use '&' for a bitwise operation
343 | if (NSEC_PER_SEC % HZ &&
| ^~
| &
drivers/gpu/drm/v3d/v3d_drv.h:343:24: note: remove constant to silence this warning
1 warning generated.
Turn this into an explicit comparison against zero to make the
expression a boolean to make it clear this should be a logical check,
not a bitwise one.
Link: https://reviews.llvm.org/D142609
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230718-nsecs_to_jiffies_timeout-constant-logical-operand-v1-1-36ed8fc8faea@kernel.org
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.