linux_dsm_epyc7002/arch/sparc/include/asm/jump_label.h

#ifndef _ASM_SPARC_JUMP_LABEL_H
#define _ASM_SPARC_JUMP_LABEL_H

#ifdef __KERNEL__

#include <linux/types.h>

#define JUMP_LABEL_NOP_SIZE 4

static __always_inline bool arch_static_branch(struct static_key *key)
{
		asm goto("1:\n\t"
			 "nop\n\t"
			 "nop\n\t"
			 ".pushsection __jump_table,  \"aw\"\n\t"
			 ".align 4\n\t"
			 ".word 1b, %l[l_yes], %c0\n\t"
			 ".popsection \n\t"
			 : :  "i" (key) : : l_yes);
	return false;
l_yes:
	return true;
}

#endif /* __KERNEL__ */

typedef u32 jump_label_t;

struct jump_entry {
	jump_label_t code;
	jump_label_t target;
	jump_label_t key;
};

#endif
jump label: Add sparc64 support Add jump label support for sparc64. Signed-off-by: David S. Miller <davem@davemloft.net> LKML-Reference: <3b5b071fcdb2afb7f67cacecfa78b14c740278a7.1284733808.git.jbaron@redhat.com> Signed-off-by: Jason Baron <jbaron@redhat.com> [ cleaned up some formatting ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org> 2010-09-17 22:09:25 +07:00			`#ifndef _ASM_SPARC_JUMP_LABEL_H`
			`#define _ASM_SPARC_JUMP_LABEL_H`

			`#ifdef __KERNEL__`

			`#include <linux/types.h>`

			`#define JUMP_LABEL_NOP_SIZE 4`

static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc\|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu> 2012-02-24 14:31:31 +07:00			`static __always_inline bool arch_static_branch(struct static_key *key)`
jump label: Introduce static_branch() interface Introduce: static __always_inline bool static_branch(struct jump_label_key key); instead of the old JUMP_LABEL(key, label) macro. In this way, jump labels become really easy to use: Define: struct jump_label_key jump_key; Can be used as: if (static_branch(&jump_key)) do unlikely code enable/disale via: jump_label_inc(&jump_key); jump_label_dec(&jump_key); that's it! For the jump labels disabled case, the static_branch() becomes an atomic_read(), and jump_label_inc()/dec() are simply atomic_inc(), atomic_dec() operations. We show testing results for this change below. Thanks to H. Peter Anvin for suggesting the 'static_branch()' construct. Since we now require a 'struct jump_label_key key', we can store a pointer into the jump table addresses. In this way, we can enable/disable jump labels, in basically constant time. This change allows us to completely remove the previous hashtable scheme. Thanks to Peter Zijlstra for this re-write. Testing: I ran a series of 'tbench 20' runs 5 times (with reboots) for 3 configurations, where tracepoints were disabled. jump label configured in avg: 815.6 jump label not configured in (using atomic reads) avg: 800.1 jump label not configured in (regular reads) avg: 803.4 Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20110316212947.GA8792@redhat.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Suggested-by: H. Peter Anvin <hpa@linux.intel.com> Tested-by: David Daney <ddaney@caviumnetworks.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> 2011-03-17 04:29:47 +07:00			`{`
			`asm goto("1:\n\t"`
			`"nop\n\t"`
			`"nop\n\t"`
			`".pushsection __jump_table, \"aw\"\n\t"`
			`".align 4\n\t"`
			`".word 1b, %l[l_yes], %c0\n\t"`
			`".popsection \n\t"`
			`: : "i" (key) : : l_yes);`
			`return false;`
			`l_yes:`
			`return true;`
			`}`
jump label: Add sparc64 support Add jump label support for sparc64. Signed-off-by: David S. Miller <davem@davemloft.net> LKML-Reference: <3b5b071fcdb2afb7f67cacecfa78b14c740278a7.1284733808.git.jbaron@redhat.com> Signed-off-by: Jason Baron <jbaron@redhat.com> [ cleaned up some formatting ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org> 2010-09-17 22:09:25 +07:00
			`#endif /* __KERNEL__ */`

			`typedef u32 jump_label_t;`

			`struct jump_entry {`
			`jump_label_t code;`
			`jump_label_t target;`
			`jump_label_t key;`
			`};`

			`#endif`