Commit d7c176e9 authored by Carlos Llamas's avatar Carlos Llamas Committed by Jonathan Corbet
Browse files

docs: printk-formats: update size-casting examples 



Since commit 72deb455 ("block: remove CONFIG_LBDAF") sector_t and
blkcnt_t types are no longer variable in size, making them unsuitable
examples for casting to the largest possible type. This patch replaces
such examples with cycles_t and blk_status_t types, whose sizes depend
on architecture and config options respectively.

Signed-off-by: default avatarCarlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20210609195058.3518943-1-cmllamas@google.com


Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent a9edc03f

Documentation/core-api/printk-formats.rst

+4 −5
Original line number Diff line number Diff line
@@ -37,14 +37,13 @@ Integer types 
		u64			%llu or %llx





If <type> is dependent on a config option for its size (e.g., sector_t,

blkcnt_t) or is architecture-dependent for its size (e.g., tcflag_t), use a

format specifier of its largest possible type and explicitly cast to it.

If <type> is architecture-dependent for its size (e.g., cycles_t, tcflag_t) or

is dependent on a config option for its size (e.g., blk_status_t), use a format

specifier of its largest possible type and explicitly cast to it.



Example::



	printk("test: sector number/total blocks: %llu/%llu\n",

		(unsigned long long)sector, (unsigned long long)blockcount);

	printk("test: latency: %llu cycles\n", (unsigned long long)time);



Reminder: sizeof() returns type size_t.