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Wysocki" , Danilo Krummrich , Andrew Morton , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrzej Hajda X-Mailer: b4 0.15-dev-47773 X-Developer-Signature: v=1; a=openpgp-sha256; l=1947; i=andrzej.hajda@intel.com; h=from:subject:message-id; bh=BidZ//3QtMfU86Ob65UNf2tBPu4j0g1ruYdm5SKevM8=; b=owEB7QES/pANAwAKASNispPeEP3XAcsmYgBpLWCCqgrlEBLHWYOOFjlFGD6Tu10XWZeK7VfDi s7v0zzoNeGJAbMEAAEKAB0WIQT8qEQxNN2/XeF/A00jYrKT3hD91wUCaS1gggAKCRAjYrKT3hD9 15gVDAClfsOsq5oWz8xyehgotr2qX0EkmLOP4SHstCcoZwpFPmgVpFXJZsbrEQq61BdxV34LMGS RUseDWoRcuoe+E01xsLw/6ML5YqOYeBYhebiw4yLIi+rSgnLkfa3SIiSMxlYvqwTqL7StV50nBy /1Ig+eXoLoOddJtC+dsWQmbBagt97nH1D10ROZ621wfpQ4GV4BuOXk2xt0g0qnpnJarOFtZx5aa UeKzZQC8rzlcODyO9v4NlizeITJjxeF+FGCVP0mTHPRoZmGfOilPj70Ow+35ufdkEvCZw7QZHIY 5eePg5IfX5fJbtnx4rBVUfU2xReXZgRVFQNuc+QXIdHA7jcwMYPp7tjSIFxGRIYJfqCqZNOhBv4 dP5JfXLQbmtf3UyTztapg8k4Hh/PV7DCptMswCWa6jlDQfO5nW8Y0gBg9xgicCOJIzQzseOr1Nn PH45VkUjdFzO5bmNCnLNzdg/t6SYU0oYSUeVCmq6ETxynodehHR6UD/Erlg+kq10ezhVE= X-Developer-Key: i=andrzej.hajda@intel.com; a=openpgp; fpr=FCA8443134DDBF5DE17F034D2362B293DE10FDD7 X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 2B321120019 X-Stat-Signature: qnk9jdfhjc6fcpq6jhozqu67y5dswrnc X-Rspam-User: X-HE-Tag: 1764581613-592367 X-HE-Meta: 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 xUQtYi6Q oHEAde599btSDF6Ull9+V5ddDtfGKh40PkpsZJcl5yrpgpzLPIpdVC5RkfrYBSknslWe5qO0FsKC7SpqTbFk/+PHF5mk+pCo4IDqcwKRETRRm+ZAqEvy1r6CkCUWpZJBazmA6mf03zlEjbv8BjWXRqUH/HTsqYBsi/+ZUXm6HRH4LzezqRgPeKZYq3+/plxRtiWe25mTyTFKHTVykgxjZPqTyvErEfyN0i6UpGV3/tbN9XCg= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: struct va_format is used to facilitate implementation of variadic functions. Most of variadic users do not parse arguments one by one, they just forward them to some helper via va_format pointer. Introduced helpers simplifies it more. Signed-off-by: Andrzej Hajda --- include/linux/printk.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/include/linux/printk.h b/include/linux/printk.h index 45c663124c9b..6fd817ce29a6 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -87,6 +87,36 @@ struct va_format { va_list *va; }; +/* Special macro used only by callers of va_format_call to position va_format argument */ +#define va_format_arg (&vaf) + +/** + * va_format_call() - forward variable arguments to va_format aware function + * @_fmt: format used by @_func function + * @_func: function which should be called + * @_args: arguments passed to @_func. Exactly one of them must be va_format_arg, + * to indicate position of *va_format type arg in arguments of @_func. + * + * Many variadic functions just forwards their variadic arguments to some helper + * function via va_format pointer. It involves few common steps encapsulated in + * this macro. The macro is accompanied by va_format_arg macro, described above. + * Sample implementation of common helper: + * void dev_err(struct device *dev, const char* fmt, ...) + * { + * va_format_call(fmt, pr_err, "%s %s: %pV", dev_driver_string(dev), + * dev_name(dev), va_format_arg); + * } + */ +#define va_format_call(_fmt, _func, _args...) \ +({ \ + va_list ap; \ + struct va_format vaf = { .fmt = _fmt, .va = &ap }; \ + \ + va_start(ap, _fmt); \ + _func(_args); \ + va_end(ap); \ +}) + /* * FW_BUG * Add this to a message where you are sure the firmware is buggy or behaves -- 2.43.0