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Merge branch 'perf/rbtree_copy' of git://git.kernel.org/pub/scm/linux…
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…/kernel/git/acme/linux into perf/urgent

Pull rbtree build fix from Arnaldo Carvalho de Melo.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar committed Jul 6, 2015
2 parents d770e55 + 307bc97 commit d2d61ed
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58 changes: 58 additions & 0 deletions tools/include/linux/compiler.h
Original file line number Diff line number Diff line change
Expand Up @@ -41,4 +41,62 @@

#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))

#include <linux/types.h>

static __always_inline void __read_once_size(const volatile void *p, void *res, int size)
{
switch (size) {
case 1: *(__u8 *)res = *(volatile __u8 *)p; break;
case 2: *(__u16 *)res = *(volatile __u16 *)p; break;
case 4: *(__u32 *)res = *(volatile __u32 *)p; break;
case 8: *(__u64 *)res = *(volatile __u64 *)p; break;
default:
barrier();
__builtin_memcpy((void *)res, (const void *)p, size);
barrier();
}
}

static __always_inline void __write_once_size(volatile void *p, void *res, int size)
{
switch (size) {
case 1: *(volatile __u8 *)p = *(__u8 *)res; break;
case 2: *(volatile __u16 *)p = *(__u16 *)res; break;
case 4: *(volatile __u32 *)p = *(__u32 *)res; break;
case 8: *(volatile __u64 *)p = *(__u64 *)res; break;
default:
barrier();
__builtin_memcpy((void *)p, (const void *)res, size);
barrier();
}
}

/*
* Prevent the compiler from merging or refetching reads or writes. The
* compiler is also forbidden from reordering successive instances of
* READ_ONCE, WRITE_ONCE and ACCESS_ONCE (see below), but only when the
* compiler is aware of some particular ordering. One way to make the
* compiler aware of ordering is to put the two invocations of READ_ONCE,
* WRITE_ONCE or ACCESS_ONCE() in different C statements.
*
* In contrast to ACCESS_ONCE these two macros will also work on aggregate
* data types like structs or unions. If the size of the accessed data
* type exceeds the word size of the machine (e.g., 32 bits or 64 bits)
* READ_ONCE() and WRITE_ONCE() will fall back to memcpy and print a
* compile-time warning.
*
* Their two major use cases are: (1) Mediating communication between
* process-level code and irq/NMI handlers, all running on the same CPU,
* and (2) Ensuring that the compiler does not fold, spindle, or otherwise
* mutilate accesses that either do not require ordering or that interact
* with an explicit memory barrier or atomic instruction that provides the
* required ordering.
*/

#define READ_ONCE(x) \
({ union { typeof(x) __val; char __c[1]; } __u; __read_once_size(&(x), __u.__c, sizeof(x)); __u.__val; })

#define WRITE_ONCE(x, val) \
({ union { typeof(x) __val; char __c[1]; } __u = { .__val = (val) }; __write_once_size(&(x), __u.__c, sizeof(x)); __u.__val; })

#endif /* _TOOLS_LINUX_COMPILER_H */
10 changes: 0 additions & 10 deletions tools/include/linux/export.h

This file was deleted.

104 changes: 104 additions & 0 deletions tools/include/linux/rbtree.h
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@@ -0,0 +1,104 @@
/*
Red Black Trees
(C) 1999 Andrea Arcangeli <andrea@suse.de>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
linux/include/linux/rbtree.h
To use rbtrees you'll have to implement your own insert and search cores.
This will avoid us to use callbacks and to drop drammatically performances.
I know it's not the cleaner way, but in C (not in C++) to get
performances and genericity...
See Documentation/rbtree.txt for documentation and samples.
*/

#ifndef __TOOLS_LINUX_PERF_RBTREE_H
#define __TOOLS_LINUX_PERF_RBTREE_H

#include <linux/kernel.h>
#include <linux/stddef.h>

struct rb_node {
unsigned long __rb_parent_color;
struct rb_node *rb_right;
struct rb_node *rb_left;
} __attribute__((aligned(sizeof(long))));
/* The alignment might seem pointless, but allegedly CRIS needs it */

struct rb_root {
struct rb_node *rb_node;
};


#define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3))

#define RB_ROOT (struct rb_root) { NULL, }
#define rb_entry(ptr, type, member) container_of(ptr, type, member)

#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)

/* 'empty' nodes are nodes that are known not to be inserted in an rbtree */
#define RB_EMPTY_NODE(node) \
((node)->__rb_parent_color == (unsigned long)(node))
#define RB_CLEAR_NODE(node) \
((node)->__rb_parent_color = (unsigned long)(node))


extern void rb_insert_color(struct rb_node *, struct rb_root *);
extern void rb_erase(struct rb_node *, struct rb_root *);


/* Find logical next and previous nodes in a tree */
extern struct rb_node *rb_next(const struct rb_node *);
extern struct rb_node *rb_prev(const struct rb_node *);
extern struct rb_node *rb_first(const struct rb_root *);
extern struct rb_node *rb_last(const struct rb_root *);

/* Postorder iteration - always visit the parent after its children */
extern struct rb_node *rb_first_postorder(const struct rb_root *);
extern struct rb_node *rb_next_postorder(const struct rb_node *);

/* Fast replacement of a single node without remove/rebalance/add/rebalance */
extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
struct rb_root *root);

static inline void rb_link_node(struct rb_node *node, struct rb_node *parent,
struct rb_node **rb_link)
{
node->__rb_parent_color = (unsigned long)parent;
node->rb_left = node->rb_right = NULL;

*rb_link = node;
}

#define rb_entry_safe(ptr, type, member) \
({ typeof(ptr) ____ptr = (ptr); \
____ptr ? rb_entry(____ptr, type, member) : NULL; \
})


/*
* Handy for checking that we are not deleting an entry that is
* already in a list, found in block/{blk-throttle,cfq-iosched}.c,
* probably should be moved to lib/rbtree.c...
*/
static inline void rb_erase_init(struct rb_node *n, struct rb_root *root)
{
rb_erase(n, root);
RB_CLEAR_NODE(n);
}
#endif /* __TOOLS_LINUX_PERF_RBTREE_H */
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