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David Howells
cd888e8a12
[ Upstream commit 9607871f37 ]
The following code in the linux/ndctl header file:
static inline const char *nvdimm_bus_cmd_name(unsigned cmd)
{
static const char * const names[] = {
[ND_CMD_ARS_CAP] = "ars_cap",
[ND_CMD_ARS_START] = "ars_start",
[ND_CMD_ARS_STATUS] = "ars_status",
[ND_CMD_CLEAR_ERROR] = "clear_error",
[ND_CMD_CALL] = "cmd_call",
};
if (cmd < ARRAY_SIZE(names) && names[cmd])
return names[cmd];
return "unknown";
}
is broken in a number of ways:
(1) ARRAY_SIZE() is not generally defined.
(2) g++ does not support "non-trivial" array initialisers fully yet.
(3) Every file that calls this function will acquire a copy of names[].
The same goes for nvdimm_cmd_name().
Fix all three by converting to a switch statement where each case returns a
string. That way if cmd is a constant, the compiler can trivially reduce it
and, if not, the compiler can use a shared lookup table if it thinks that is
more efficient.
A better way would be to remove these functions and their arrays from the
header entirely.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.