diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2020-08-18 15:57:45 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2020-09-01 09:58:05 +0200 |
| commit | 1e7e47883830aae5e8246a22ca2fc6883c61acdf (patch) | |
| tree | 225d6e2fc34af21e42996c0434f871486c586a2f /tools/include | |
| parent | e6d6c071f22de29e4993784fc00cd2202b7ba149 (diff) | |
x86/static_call: Add inline static call implementation for x86-64
Add the inline static call implementation for x86-64. The generated code
is identical to the out-of-line case, except we move the trampoline into
it's own section.
Objtool uses the trampoline naming convention to detect all the call
sites. It then annotates those call sites in the .static_call_sites
section.
During boot (and module init), the call sites are patched to call
directly into the destination function. The temporary trampoline is
then no longer used.
[peterz: merged trampolines, put trampoline in section]
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20200818135804.864271425@infradead.org
Diffstat (limited to 'tools/include')
| -rw-r--r-- | tools/include/linux/static_call_types.h | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/tools/include/linux/static_call_types.h b/tools/include/linux/static_call_types.h new file mode 100644 index 000000000000..408d345d83e1 --- /dev/null +++ b/tools/include/linux/static_call_types.h @@ -0,0 +1,28 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _STATIC_CALL_TYPES_H +#define _STATIC_CALL_TYPES_H + +#include <linux/types.h> +#include <linux/stringify.h> + +#define STATIC_CALL_KEY_PREFIX __SCK__ +#define STATIC_CALL_KEY_PREFIX_STR __stringify(STATIC_CALL_KEY_PREFIX) +#define STATIC_CALL_KEY_PREFIX_LEN (sizeof(STATIC_CALL_KEY_PREFIX_STR) - 1) +#define STATIC_CALL_KEY(name) __PASTE(STATIC_CALL_KEY_PREFIX, name) + +#define STATIC_CALL_TRAMP_PREFIX __SCT__ +#define STATIC_CALL_TRAMP_PREFIX_STR __stringify(STATIC_CALL_TRAMP_PREFIX) +#define STATIC_CALL_TRAMP_PREFIX_LEN (sizeof(STATIC_CALL_TRAMP_PREFIX_STR) - 1) +#define STATIC_CALL_TRAMP(name) __PASTE(STATIC_CALL_TRAMP_PREFIX, name) +#define STATIC_CALL_TRAMP_STR(name) __stringify(STATIC_CALL_TRAMP(name)) + +/* + * The static call site table needs to be created by external tooling (objtool + * or a compiler plugin). + */ +struct static_call_site { + s32 addr; + s32 key; +}; + +#endif /* _STATIC_CALL_TYPES_H */ |