| #ifndef _BACKPORTS_LINUX_STATIC_KEY_H |
| #define _BACKPORTS_LINUX_STATIC_KEY_H 1 |
| |
| #include <linux/version.h> |
| |
| #if LINUX_VERSION_IS_GEQ(3,3,0) /* kernels >= 3.3 */ |
| /* |
| * XXX: NOTE! |
| * |
| * Some 3.3 kernels carry <linux/static.h> but some don't even though its |
| * its including <linux/jump_label.h>. What makes it more confusing is that |
| * later all this got shuffled. The safe thing to do then is to just assume |
| * kernels 3.3..3.4 don't have it and include <linux/jump_label.h> instead, |
| * and for newer kernels include <linux/static_key.h>. |
| */ |
| #if LINUX_VERSION_IS_GEQ(3,5,0) |
| #include_next <linux/static_key.h> |
| #else |
| #include <linux/jump_label.h> |
| #endif |
| |
| #else /* kernels < 3.3 */ |
| /* |
| * in between 2.6.37 - 3.5 there's a slew of changes that make |
| * it hard to backport this properly. If you are interested in |
| * trying you can use this as reference: |
| * |
| * http://drvbp1.linux-foundation.org/~mcgrof/examples/2014/04/01/backport-static-keys.patch |
| * |
| * And these notes: |
| * |
| * < v2.6.37 - No tracing support |
| * bf5438fc - v2.6.37 - Jump label support added primarily for tracing but |
| * tracing was broken, later kernels started sporting |
| * functional tracing. |
| * d430d3d7e - v3.0 - Static branch optimizations for jump labels |
| * c5905afb - v3.3 - Static keys split out, note on the below issue |
| * c5905afb - v3.5 - git describe --contains c5905afb claims but not true! |
| * c4b2c0c5f - v3.13 - Adds static_key_initialized(), STATIC_KEY_CHECK_USE() |
| * |
| * Because all of this we skip 2.6.37 - 3.3 but and adding support for older |
| * can be done by of carrying over the non-architecture optimized code. |
| * Carrying new changes into this file is a burden though so if we really |
| * find use for this we could just split the non optimized versions upstream |
| * and copy that through an automatic process. |
| */ |
| #endif /* kernels < 3.3 */ |
| |
| #endif /* _BACKPORTS_LINUX_STATIC_KEY_H */ |
