Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2025-01-09 23:39:18 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
linux-next/include/linux/percpu.h
Christoph Lameter b3ca1c10d7 percpu: add raw_cpu_ops 
The kernel has never been audited to ensure that this_cpu operations are
consistently used throughout the kernel.  The code generated in many
places can be improved through the use of this_cpu operations (which
uses a segment register for relocation of per cpu offsets instead of
performing address calculations).

The patch set also addresses various consistency issues in general with
the per cpu macros.

A. The semantics of __this_cpu_ptr() differs from this_cpu_ptr only
   because checks are skipped. This is typically shown through a raw_
   prefix. So this patch set changes the places where __this_cpu_ptr()
   is used to raw_cpu_ptr().

B. There has been the long term wish by some that __this_cpu operations
   would check for preemption. However, there are cases where preemption
   checks need to be skipped. This patch set adds raw_cpu operations that
   do not check for preemption and then adds preemption checks to the
   __this_cpu operations.

C. The use of __get_cpu_var is always a reference to a percpu variable
   that can also be handled via a this_cpu operation. This patch set
   replaces all uses of __get_cpu_var with this_cpu operations.

D. We can then use this_cpu RMW operations in various places replacing
   sequences of instructions by a single one.

E. The use of this_cpu operations throughout will allow other arches than
   x86 to implement optimized references and RMV operations to work with
   per cpu local data.

F. The use of this_cpu operations opens up the possibility to
   further optimize code that relies on synchronization through
   per cpu data.

The patch set works in a couple of stages:

I. Patch 1 adds the additional raw_cpu operations and raw_cpu_ptr().
    Also converts the existing __this_cpu_xx_# primitive in the x86
    code to raw_cpu_xx_#.

II. Patch 2-4 use the raw_cpu operations in places that would give
     us false positives once they are enabled.

III. Patch 5 adds preemption checks to __this_cpu operations to allow
    checking if preemption is properly disabled when these functions
    are used.

IV. Patches 6-20 are patches that simply replace uses of __get_cpu_var
   with this_cpu_ptr. They do not depend on any changes to the percpu
   code. No preemption tests are skipped if they are applied.

V. Patches 21-46 are conversion patches that use this_cpu operations
   in various kernel subsystems/drivers or arch code.

VI.  Patches 47/48 (not included in this series) remove no longer used
    functions (__this_cpu_ptr and __get_cpu_var).  These should only be
    applied after all the conversion patches have made it and after we
    have done additional passes through the kernel to ensure that none of
    the uses of these functions remain.

This patch (of 46):

The patches following this one will add preemption checks to __this_cpu
ops so we need to have an alternative way to use this_cpu operations
without preemption checks.

raw_cpu_ops will be the basis for all other ops since these will be the
operations that do not implement any checks.

Primitive operations are renamed by this patch from __this_cpu_xxx to
raw_cpu_xxxx.

Also change the uses of the x86 percpu primitives in preempt.h.
These depend directly on asm/percpu.h (header #include nesting issue).

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Alex Shi <alex.shi@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: David Daney <david.daney@cavium.com>
Cc: David Miller <davem@davemloft.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Hedi Berriche <hedi@sgi.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mike Travis <travis@sgi.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Robert Richter <rric@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:36:13 -07:00

787 lines
25 KiB
C
Raw Blame History

#ifndef __LINUX_PERCPU_H
#define __LINUX_PERCPU_H
#include <linux/mmdebug.h>
#include <linux/preempt.h>
#include <linux/smp.h>
#include <linux/cpumask.h>
#include <linux/pfn.h>
#include <linux/init.h>
#include <asm/percpu.h>
/* enough to cover all DEFINE_PER_CPUs in modules */
#ifdef CONFIG_MODULES
#define PERCPU_MODULE_RESERVE (8 << 10)
#else
#define PERCPU_MODULE_RESERVE 0
#endif
#ifndef PERCPU_ENOUGH_ROOM
#define PERCPU_ENOUGH_ROOM \
(ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
PERCPU_MODULE_RESERVE)
#endif
/*
* Must be an lvalue. Since @var must be a simple identifier,
* we force a syntax error here if it isn't.
*/
#define get_cpu_var(var) (*({ \
preempt_disable(); \
&__get_cpu_var(var); }))
/*
* The weird & is necessary because sparse considers (void)(var) to be
* a direct dereference of percpu variable (var).
*/
#define put_cpu_var(var) do { \
(void)&(var); \
preempt_enable(); \
} while (0)
#define get_cpu_ptr(var) ({ \
preempt_disable(); \
this_cpu_ptr(var); })
#define put_cpu_ptr(var) do { \
(void)(var); \
preempt_enable(); \
} while (0)
/* minimum unit size, also is the maximum supported allocation size */
#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10)
/*
* Percpu allocator can serve percpu allocations before slab is
* initialized which allows slab to depend on the percpu allocator.
* The following two parameters decide how much resource to
* preallocate for this. Keep PERCPU_DYNAMIC_RESERVE equal to or
* larger than PERCPU_DYNAMIC_EARLY_SIZE.
*/
#define PERCPU_DYNAMIC_EARLY_SLOTS 128
#define PERCPU_DYNAMIC_EARLY_SIZE (12 << 10)
/*
* PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
* back on the first chunk for dynamic percpu allocation if arch is
* manually allocating and mapping it for faster access (as a part of
* large page mapping for example).
*
* The following values give between one and two pages of free space
* after typical minimal boot (2-way SMP, single disk and NIC) with
* both defconfig and a distro config on x86_64 and 32. More
* intelligent way to determine this would be nice.
*/
#if BITS_PER_LONG > 32
#define PERCPU_DYNAMIC_RESERVE (20 << 10)
#else
#define PERCPU_DYNAMIC_RESERVE (12 << 10)
#endif
extern void *pcpu_base_addr;
extern const unsigned long *pcpu_unit_offsets;
struct pcpu_group_info {
int nr_units; /* aligned # of units */
unsigned long base_offset; /* base address offset */
unsigned int *cpu_map; /* unit->cpu map, empty
* entries contain NR_CPUS */
};
struct pcpu_alloc_info {
size_t static_size;
size_t reserved_size;
size_t dyn_size;
size_t unit_size;
size_t atom_size;
size_t alloc_size;
size_t __ai_size; /* internal, don't use */
int nr_groups; /* 0 if grouping unnecessary */
struct pcpu_group_info groups[];
};
enum pcpu_fc {
PCPU_FC_AUTO,
PCPU_FC_EMBED,
PCPU_FC_PAGE,
PCPU_FC_NR,
};
extern const char * const pcpu_fc_names[PCPU_FC_NR];
extern enum pcpu_fc pcpu_chosen_fc;
typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
size_t align);
typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
int nr_units);
extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
void *base_addr);
#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
size_t atom_size,
pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
pcpu_fc_alloc_fn_t alloc_fn,
pcpu_fc_free_fn_t free_fn);
#endif
#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
extern int __init pcpu_page_first_chunk(size_t reserved_size,
pcpu_fc_alloc_fn_t alloc_fn,
pcpu_fc_free_fn_t free_fn,
pcpu_fc_populate_pte_fn_t populate_pte_fn);
#endif
/*
* Use this to get to a cpu's version of the per-cpu object
* dynamically allocated. Non-atomic access to the current CPU's
* version should probably be combined with get_cpu()/put_cpu().
*/
#ifdef CONFIG_SMP
#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
#else
#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
#endif
extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
extern bool is_kernel_percpu_address(unsigned long addr);
#if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
extern void __init setup_per_cpu_areas(void);
#endif
extern void __init percpu_init_late(void);
extern void __percpu *__alloc_percpu(size_t size, size_t align);
extern void free_percpu(void __percpu *__pdata);
extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
#define alloc_percpu(type) \
(typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
/*
* Branching function to split up a function into a set of functions that
* are called for different scalar sizes of the objects handled.
*/
extern void __bad_size_call_parameter(void);
#define __pcpu_size_call_return(stem, variable) \
({ typeof(variable) pscr_ret__; \
__verify_pcpu_ptr(&(variable)); \
switch(sizeof(variable)) { \
case 1: pscr_ret__ = stem##1(variable);break; \
case 2: pscr_ret__ = stem##2(variable);break; \
case 4: pscr_ret__ = stem##4(variable);break; \
case 8: pscr_ret__ = stem##8(variable);break; \
default: \
__bad_size_call_parameter();break; \
} \
pscr_ret__; \
})
#define __pcpu_size_call_return2(stem, variable, ...) \
({ \
typeof(variable) pscr2_ret__; \
__verify_pcpu_ptr(&(variable)); \
switch(sizeof(variable)) { \
case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \
case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \
case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \
case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \
default: \
__bad_size_call_parameter(); break; \
} \
pscr2_ret__; \
})
/*
* Special handling for cmpxchg_double. cmpxchg_double is passed two
* percpu variables. The first has to be aligned to a double word
* boundary and the second has to follow directly thereafter.
* We enforce this on all architectures even if they don't support
* a double cmpxchg instruction, since it's a cheap requirement, and it
* avoids breaking the requirement for architectures with the instruction.
*/
#define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \
({ \
bool pdcrb_ret__; \
__verify_pcpu_ptr(&pcp1); \
BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \
VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \
VM_BUG_ON((unsigned long)(&pcp2) != \
(unsigned long)(&pcp1) + sizeof(pcp1)); \
switch(sizeof(pcp1)) { \
case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \
case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \
case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \
case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \
default: \
__bad_size_call_parameter(); break; \
} \
pdcrb_ret__; \
})
#define __pcpu_size_call(stem, variable, ...) \
do { \
__verify_pcpu_ptr(&(variable)); \
switch(sizeof(variable)) { \
case 1: stem##1(variable, __VA_ARGS__);break; \
case 2: stem##2(variable, __VA_ARGS__);break; \
case 4: stem##4(variable, __VA_ARGS__);break; \
case 8: stem##8(variable, __VA_ARGS__);break; \
default: \
__bad_size_call_parameter();break; \
} \
} while (0)
/*
* this_cpu operations (C) 2008-2013 Christoph Lameter <cl@linux.com>
*
* Optimized manipulation for memory allocated through the per cpu
* allocator or for addresses of per cpu variables.
*
* These operation guarantee exclusivity of access for other operations
* on the *same* processor. The assumption is that per cpu data is only
* accessed by a single processor instance (the current one).
*
* The first group is used for accesses that must be done in a
* preemption safe way since we know that the context is not preempt
* safe. Interrupts may occur. If the interrupt modifies the variable
* too then RMW actions will not be reliable.
*
* The arch code can provide optimized functions in two ways:
*
* 1. Override the function completely. F.e. define this_cpu_add().
* The arch must then ensure that the various scalar format passed
* are handled correctly.
*
* 2. Provide functions for certain scalar sizes. F.e. provide
* this_cpu_add_2() to provide per cpu atomic operations for 2 byte
* sized RMW actions. If arch code does not provide operations for
* a scalar size then the fallback in the generic code will be
* used.
*/
#define _this_cpu_generic_read(pcp) \
({ typeof(pcp) ret__; \
preempt_disable(); \
ret__ = *this_cpu_ptr(&(pcp)); \
preempt_enable(); \
ret__; \
})
#ifndef this_cpu_read
# ifndef this_cpu_read_1
# define this_cpu_read_1(pcp) _this_cpu_generic_read(pcp)
# endif
# ifndef this_cpu_read_2
# define this_cpu_read_2(pcp) _this_cpu_generic_read(pcp)
# endif
# ifndef this_cpu_read_4
# define this_cpu_read_4(pcp) _this_cpu_generic_read(pcp)
# endif
# ifndef this_cpu_read_8
# define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp)
# endif
# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
#endif
#define _this_cpu_generic_to_op(pcp, val, op) \
do { \
unsigned long flags; \
raw_local_irq_save(flags); \
*raw_cpu_ptr(&(pcp)) op val; \
raw_local_irq_restore(flags); \
} while (0)
#ifndef this_cpu_write
# ifndef this_cpu_write_1
# define this_cpu_write_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef this_cpu_write_2
# define this_cpu_write_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef this_cpu_write_4
# define this_cpu_write_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef this_cpu_write_8
# define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
#endif
#ifndef this_cpu_add
# ifndef this_cpu_add_1
# define this_cpu_add_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef this_cpu_add_2
# define this_cpu_add_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef this_cpu_add_4
# define this_cpu_add_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef this_cpu_add_8
# define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
#endif
#ifndef this_cpu_sub
# define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(typeof(pcp))(val))
#endif
#ifndef this_cpu_inc
# define this_cpu_inc(pcp) this_cpu_add((pcp), 1)
#endif
#ifndef this_cpu_dec
# define this_cpu_dec(pcp) this_cpu_sub((pcp), 1)
#endif
#ifndef this_cpu_and
# ifndef this_cpu_and_1
# define this_cpu_and_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef this_cpu_and_2
# define this_cpu_and_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef this_cpu_and_4
# define this_cpu_and_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef this_cpu_and_8
# define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
#endif
#ifndef this_cpu_or
# ifndef this_cpu_or_1
# define this_cpu_or_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef this_cpu_or_2
# define this_cpu_or_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef this_cpu_or_4
# define this_cpu_or_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef this_cpu_or_8
# define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
#endif
#define _this_cpu_generic_add_return(pcp, val) \
({ \
typeof(pcp) ret__; \
unsigned long flags; \
raw_local_irq_save(flags); \
raw_cpu_add(pcp, val); \
ret__ = raw_cpu_read(pcp); \
raw_local_irq_restore(flags); \
ret__; \
})
#ifndef this_cpu_add_return
# ifndef this_cpu_add_return_1
# define this_cpu_add_return_1(pcp, val) _this_cpu_generic_add_return(pcp, val)
# endif
# ifndef this_cpu_add_return_2
# define this_cpu_add_return_2(pcp, val) _this_cpu_generic_add_return(pcp, val)
# endif
# ifndef this_cpu_add_return_4
# define this_cpu_add_return_4(pcp, val) _this_cpu_generic_add_return(pcp, val)
# endif
# ifndef this_cpu_add_return_8
# define this_cpu_add_return_8(pcp, val) _this_cpu_generic_add_return(pcp, val)
# endif
# define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
#endif
#define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(typeof(pcp))(val))
#define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1)
#define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1)
#define _this_cpu_generic_xchg(pcp, nval) \
({ typeof(pcp) ret__; \
unsigned long flags; \
raw_local_irq_save(flags); \
ret__ = raw_cpu_read(pcp); \
raw_cpu_write(pcp, nval); \
raw_local_irq_restore(flags); \
ret__; \
})
#ifndef this_cpu_xchg
# ifndef this_cpu_xchg_1
# define this_cpu_xchg_1(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
# endif
# ifndef this_cpu_xchg_2
# define this_cpu_xchg_2(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
# endif
# ifndef this_cpu_xchg_4
# define this_cpu_xchg_4(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
# endif
# ifndef this_cpu_xchg_8
# define this_cpu_xchg_8(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
# endif
# define this_cpu_xchg(pcp, nval) \
__pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
#endif
#define _this_cpu_generic_cmpxchg(pcp, oval, nval) \
({ \
typeof(pcp) ret__; \
unsigned long flags; \
raw_local_irq_save(flags); \
ret__ = raw_cpu_read(pcp); \
if (ret__ == (oval)) \
raw_cpu_write(pcp, nval); \
raw_local_irq_restore(flags); \
ret__; \
})
#ifndef this_cpu_cmpxchg
# ifndef this_cpu_cmpxchg_1
# define this_cpu_cmpxchg_1(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
# endif
# ifndef this_cpu_cmpxchg_2
# define this_cpu_cmpxchg_2(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
# endif
# ifndef this_cpu_cmpxchg_4
# define this_cpu_cmpxchg_4(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
# endif
# ifndef this_cpu_cmpxchg_8
# define this_cpu_cmpxchg_8(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
# endif
# define this_cpu_cmpxchg(pcp, oval, nval) \
__pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
#endif
/*
* cmpxchg_double replaces two adjacent scalars at once. The first
* two parameters are per cpu variables which have to be of the same
* size. A truth value is returned to indicate success or failure
* (since a double register result is difficult to handle). There is
* very limited hardware support for these operations, so only certain
* sizes may work.
*/
#define _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
({ \
int ret__; \
unsigned long flags; \
raw_local_irq_save(flags); \
ret__ = raw_cpu_generic_cmpxchg_double(pcp1, pcp2, \
oval1, oval2, nval1, nval2); \
raw_local_irq_restore(flags); \
ret__; \
})
#ifndef this_cpu_cmpxchg_double
# ifndef this_cpu_cmpxchg_double_1
# define this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \
_this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
# endif
# ifndef this_cpu_cmpxchg_double_2
# define this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \
_this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
# endif
# ifndef this_cpu_cmpxchg_double_4
# define this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \
_this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
# endif
# ifndef this_cpu_cmpxchg_double_8
# define this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \
_this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
# endif
# define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
__pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
#endif
/*
* Generic percpu operations for contexts where we do not want to do
* any checks for preemptiosn.
*
* If there is no other protection through preempt disable and/or
* disabling interupts then one of these RMW operations can show unexpected
* behavior because the execution thread was rescheduled on another processor
* or an interrupt occurred and the same percpu variable was modified from
* the interrupt context.
*/
#ifndef raw_cpu_read
# ifndef raw_cpu_read_1
# define raw_cpu_read_1(pcp) (*raw_cpu_ptr(&(pcp)))
# endif
# ifndef raw_cpu_read_2
# define raw_cpu_read_2(pcp) (*raw_cpu_ptr(&(pcp)))
# endif
# ifndef raw_cpu_read_4
# define raw_cpu_read_4(pcp) (*raw_cpu_ptr(&(pcp)))
# endif
# ifndef raw_cpu_read_8
# define raw_cpu_read_8(pcp) (*raw_cpu_ptr(&(pcp)))
# endif
# define raw_cpu_read(pcp) __pcpu_size_call_return(raw_cpu_read_, (pcp))
#endif
#define raw_cpu_generic_to_op(pcp, val, op) \
do { \
*raw_cpu_ptr(&(pcp)) op val; \
} while (0)
#ifndef raw_cpu_write
# ifndef raw_cpu_write_1
# define raw_cpu_write_1(pcp, val) raw_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef raw_cpu_write_2
# define raw_cpu_write_2(pcp, val) raw_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef raw_cpu_write_4
# define raw_cpu_write_4(pcp, val) raw_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef raw_cpu_write_8
# define raw_cpu_write_8(pcp, val) raw_cpu_generic_to_op((pcp), (val), =)
# endif
# define raw_cpu_write(pcp, val) __pcpu_size_call(raw_cpu_write_, (pcp), (val))
#endif
#ifndef raw_cpu_add
# ifndef raw_cpu_add_1
# define raw_cpu_add_1(pcp, val) raw_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef raw_cpu_add_2
# define raw_cpu_add_2(pcp, val) raw_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef raw_cpu_add_4
# define raw_cpu_add_4(pcp, val) raw_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef raw_cpu_add_8
# define raw_cpu_add_8(pcp, val) raw_cpu_generic_to_op((pcp), (val), +=)
# endif
# define raw_cpu_add(pcp, val) __pcpu_size_call(raw_cpu_add_, (pcp), (val))
#endif
#ifndef raw_cpu_sub
# define raw_cpu_sub(pcp, val) raw_cpu_add((pcp), -(val))
#endif
#ifndef raw_cpu_inc
# define raw_cpu_inc(pcp) raw_cpu_add((pcp), 1)
#endif
#ifndef raw_cpu_dec
# define raw_cpu_dec(pcp) raw_cpu_sub((pcp), 1)
#endif
#ifndef raw_cpu_and
# ifndef raw_cpu_and_1
# define raw_cpu_and_1(pcp, val) raw_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef raw_cpu_and_2
# define raw_cpu_and_2(pcp, val) raw_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef raw_cpu_and_4
# define raw_cpu_and_4(pcp, val) raw_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef raw_cpu_and_8
# define raw_cpu_and_8(pcp, val) raw_cpu_generic_to_op((pcp), (val), &=)
# endif
# define raw_cpu_and(pcp, val) __pcpu_size_call(raw_cpu_and_, (pcp), (val))
#endif
#ifndef raw_cpu_or
# ifndef raw_cpu_or_1
# define raw_cpu_or_1(pcp, val) raw_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef raw_cpu_or_2
# define raw_cpu_or_2(pcp, val) raw_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef raw_cpu_or_4
# define raw_cpu_or_4(pcp, val) raw_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef raw_cpu_or_8
# define raw_cpu_or_8(pcp, val) raw_cpu_generic_to_op((pcp), (val), |=)
# endif
# define raw_cpu_or(pcp, val) __pcpu_size_call(raw_cpu_or_, (pcp), (val))
#endif
#define raw_cpu_generic_add_return(pcp, val) \
({ \
raw_cpu_add(pcp, val); \
raw_cpu_read(pcp); \
})
#ifndef raw_cpu_add_return
# ifndef raw_cpu_add_return_1
# define raw_cpu_add_return_1(pcp, val) raw_cpu_generic_add_return(pcp, val)
# endif
# ifndef raw_cpu_add_return_2
# define raw_cpu_add_return_2(pcp, val) raw_cpu_generic_add_return(pcp, val)
# endif
# ifndef raw_cpu_add_return_4
# define raw_cpu_add_return_4(pcp, val) raw_cpu_generic_add_return(pcp, val)
# endif
# ifndef raw_cpu_add_return_8
# define raw_cpu_add_return_8(pcp, val) raw_cpu_generic_add_return(pcp, val)
# endif
# define raw_cpu_add_return(pcp, val) \
__pcpu_size_call_return2(raw_add_return_, pcp, val)
#endif
#define raw_cpu_sub_return(pcp, val) raw_cpu_add_return(pcp, -(typeof(pcp))(val))
#define raw_cpu_inc_return(pcp) raw_cpu_add_return(pcp, 1)
#define raw_cpu_dec_return(pcp) raw_cpu_add_return(pcp, -1)
#define raw_cpu_generic_xchg(pcp, nval) \
({ typeof(pcp) ret__; \
ret__ = raw_cpu_read(pcp); \
raw_cpu_write(pcp, nval); \
ret__; \
})
#ifndef raw_cpu_xchg
# ifndef raw_cpu_xchg_1
# define raw_cpu_xchg_1(pcp, nval) raw_cpu_generic_xchg(pcp, nval)
# endif
# ifndef raw_cpu_xchg_2
# define raw_cpu_xchg_2(pcp, nval) raw_cpu_generic_xchg(pcp, nval)
# endif
# ifndef raw_cpu_xchg_4
# define raw_cpu_xchg_4(pcp, nval) raw_cpu_generic_xchg(pcp, nval)
# endif
# ifndef raw_cpu_xchg_8
# define raw_cpu_xchg_8(pcp, nval) raw_cpu_generic_xchg(pcp, nval)
# endif
# define raw_cpu_xchg(pcp, nval) \
__pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval)
#endif
#define raw_cpu_generic_cmpxchg(pcp, oval, nval) \
({ \
typeof(pcp) ret__; \
ret__ = raw_cpu_read(pcp); \
if (ret__ == (oval)) \
raw_cpu_write(pcp, nval); \
ret__; \
})
#ifndef raw_cpu_cmpxchg
# ifndef raw_cpu_cmpxchg_1
# define raw_cpu_cmpxchg_1(pcp, oval, nval) raw_cpu_generic_cmpxchg(pcp, oval, nval)
# endif
# ifndef raw_cpu_cmpxchg_2
# define raw_cpu_cmpxchg_2(pcp, oval, nval) raw_cpu_generic_cmpxchg(pcp, oval, nval)
# endif
# ifndef raw_cpu_cmpxchg_4
# define raw_cpu_cmpxchg_4(pcp, oval, nval) raw_cpu_generic_cmpxchg(pcp, oval, nval)
# endif
# ifndef raw_cpu_cmpxchg_8
# define raw_cpu_cmpxchg_8(pcp, oval, nval) raw_cpu_generic_cmpxchg(pcp, oval, nval)
# endif
# define raw_cpu_cmpxchg(pcp, oval, nval) \
__pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval)
#endif
#define raw_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
({ \
int __ret = 0; \
if (raw_cpu_read(pcp1) == (oval1) && \
raw_cpu_read(pcp2) == (oval2)) { \
raw_cpu_write(pcp1, (nval1)); \
raw_cpu_write(pcp2, (nval2)); \
__ret = 1; \
} \
(__ret); \
})
#ifndef raw_cpu_cmpxchg_double
# ifndef raw_cpu_cmpxchg_double_1
# define raw_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \
raw_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
# endif
# ifndef raw_cpu_cmpxchg_double_2
# define raw_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \
raw_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
# endif
# ifndef raw_cpu_cmpxchg_double_4
# define raw_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \
raw_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
# endif
# ifndef raw_cpu_cmpxchg_double_8
# define raw_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \
raw_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
# endif
# define raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
__pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
#endif
/*
* Generic percpu operations for context that are safe from preemption/interrupts.
* Checks will be added here soon.
*/
#ifndef __this_cpu_read
# define __this_cpu_read(pcp) __pcpu_size_call_return(raw_cpu_read_, (pcp))
#endif
#ifndef __this_cpu_write
# define __this_cpu_write(pcp, val) __pcpu_size_call(raw_cpu_write_, (pcp), (val))
#endif
#ifndef __this_cpu_add
# define __this_cpu_add(pcp, val) __pcpu_size_call(raw_cpu_add_, (pcp), (val))
#endif
#ifndef __this_cpu_sub
# define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(typeof(pcp))(val))
#endif
#ifndef __this_cpu_inc
# define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1)
#endif
#ifndef __this_cpu_dec
# define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1)
#endif
#ifndef __this_cpu_and
# define __this_cpu_and(pcp, val) __pcpu_size_call(raw_cpu_and_, (pcp), (val))
#endif
#ifndef __this_cpu_or
# define __this_cpu_or(pcp, val) __pcpu_size_call(raw_cpu_or_, (pcp), (val))
#endif
#ifndef __this_cpu_add_return
# define __this_cpu_add_return(pcp, val) \
__pcpu_size_call_return2(raw_cpu_add_return_, pcp, val)
#endif
#define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(typeof(pcp))(val))
#define __this_cpu_inc_return(pcp) __this_cpu_add_return(pcp, 1)
#define __this_cpu_dec_return(pcp) __this_cpu_add_return(pcp, -1)
#ifndef __this_cpu_xchg
# define __this_cpu_xchg(pcp, nval) \
__pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval)
#endif
#ifndef __this_cpu_cmpxchg
# define __this_cpu_cmpxchg(pcp, oval, nval) \
__pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval)
#endif
#ifndef __this_cpu_cmpxchg_double
# define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
__pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
#endif
#endif /* __LINUX_PERCPU_H */
Reference in New Issue View Git Blame Copy Permalink