v3: https://lore.kernel.org/linux-media/20211007150339.28910-1-andriy.shevchenko... v2: https://lore.kernel.org/linux-media/20211007095129.22037-1-andriy.shevchenko...
The kernel.h is a set of something which is not related to each other and often used in non-crossed compilation units, especially when drivers need only one or two macro definitions from it.
Here is the split of container_of(). The goals are the following: - untwist the dependency hell a bit - drop kernel.h inclusion where it's only used for container_of() - speed up C preprocessing.
The build speedup is 1.83% (ccache approach, see v2 cover letter for the details) 0.5% (kcbench approach, see v3 cover letter for the details)
In v4: - dropped kobject.h change (Greg) - Cc'ed more people (as per v1)
In v3: - split patch 2 to more patches (Greg) - excluded C changes (Herbert, Greg) - measured with kcbench, see below (Greg)
Andy Shevchenko (7): kernel.h: Drop unneeded <linux/kernel.h> inclusion from other headers kernel.h: Split out container_of() and typeof_member() macros kunit: Replace kernel.h with the necessary inclusions list.h: Replace kernel.h with the necessary inclusions llist: Replace kernel.h with the necessary inclusions plist: Replace kernel.h with the necessary inclusions media: entity: Replace kernel.h with the necessary inclusions
include/kunit/test.h | 14 ++++++++++++-- include/linux/container_of.h | 37 ++++++++++++++++++++++++++++++++++++ include/linux/kernel.h | 31 +----------------------------- include/linux/list.h | 6 ++++-- include/linux/llist.h | 4 +++- include/linux/plist.h | 5 ++++- include/linux/rwsem.h | 1 - include/linux/spinlock.h | 1 - include/media/media-entity.h | 3 ++- 9 files changed, 63 insertions(+), 39 deletions(-) create mode 100644 include/linux/container_of.h