Page Menu
Home
c4science
Search
Configure Global Search
Log In
Files
F78359278
pair_lj_cut_coul_long_gpu.cpp
No One
Temporary
Actions
Download File
Edit File
Delete File
View Transforms
Subscribe
Mute Notifications
Award Token
Subscribers
None
File Metadata
Details
File Info
Storage
Attached
Created
Tue, Aug 20, 03:03
Size
11 KB
Mime Type
text/x-c
Expires
Thu, Aug 22, 03:03 (2 d)
Engine
blob
Format
Raw Data
Handle
20010522
Attached To
rLAMMPS lammps
pair_lj_cut_coul_long_gpu.cpp
View Options
/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
http://lammps.sandia.gov, Sandia National Laboratories
Steve Plimpton, sjplimp@sandia.gov
Copyright (2003) Sandia Corporation. Under the terms of Contract
DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
certain rights in this software. This software is distributed under
the GNU General Public License.
See the README file in the top-level LAMMPS directory.
------------------------------------------------------------------------- */
/* ----------------------------------------------------------------------
Contributing author: Mike Brown (SNL)
------------------------------------------------------------------------- */
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include "pair_lj_cut_coul_long_gpu.h"
#include "atom.h"
#include "atom_vec.h"
#include "comm.h"
#include "force.h"
#include "neighbor.h"
#include "neigh_list.h"
#include "integrate.h"
#include "memory.h"
#include "error.h"
#include "neigh_request.h"
#include "universe.h"
#include "update.h"
#include "domain.h"
#include <string.h>
#include "kspace.h"
#include "gpu_extra.h"
#define EWALD_F 1.12837917
#define EWALD_P 0.3275911
#define A1 0.254829592
#define A2 -0.284496736
#define A3 1.421413741
#define A4 -1.453152027
#define A5 1.061405429
using
namespace
LAMMPS_NS
;
// External functions from cuda library for atom decomposition
int
ljcl_gpu_init
(
const
int
ntypes
,
double
**
cutsq
,
double
**
host_lj1
,
double
**
host_lj2
,
double
**
host_lj3
,
double
**
host_lj4
,
double
**
offset
,
double
*
special_lj
,
const
int
nlocal
,
const
int
nall
,
const
int
max_nbors
,
const
int
maxspecial
,
const
double
cell_size
,
int
&
gpu_mode
,
FILE
*
screen
,
double
**
host_cut_ljsq
,
double
host_cut_coulsq
,
double
*
host_special_coul
,
const
double
qqrd2e
,
const
double
g_ewald
);
int
ljcl_gpu_reinit
(
const
int
ntypes
,
double
**
cutsq
,
double
**
host_lj1
,
double
**
host_lj2
,
double
**
host_lj3
,
double
**
host_lj4
,
double
**
offset
,
double
**
host_lj_cutsq
);
void
ljcl_gpu_clear
();
int
**
ljcl_gpu_compute_n
(
const
int
ago
,
const
int
inum
,
const
int
nall
,
double
**
host_x
,
int
*
host_type
,
double
*
sublo
,
double
*
subhi
,
tagint
*
tag
,
int
**
nspecial
,
tagint
**
special
,
const
bool
eflag
,
const
bool
vflag
,
const
bool
eatom
,
const
bool
vatom
,
int
&
host_start
,
int
**
ilist
,
int
**
jnum
,
const
double
cpu_time
,
bool
&
success
,
double
*
host_q
,
double
*
boxlo
,
double
*
prd
);
void
ljcl_gpu_compute
(
const
int
ago
,
const
int
inum
,
const
int
nall
,
double
**
host_x
,
int
*
host_type
,
int
*
ilist
,
int
*
numj
,
int
**
firstneigh
,
const
bool
eflag
,
const
bool
vflag
,
const
bool
eatom
,
const
bool
vatom
,
int
&
host_start
,
const
double
cpu_time
,
bool
&
success
,
double
*
host_q
,
const
int
nlocal
,
double
*
boxlo
,
double
*
prd
);
double
ljcl_gpu_bytes
();
/* ---------------------------------------------------------------------- */
PairLJCutCoulLongGPU
::
PairLJCutCoulLongGPU
(
LAMMPS
*
lmp
)
:
PairLJCutCoulLong
(
lmp
),
gpu_mode
(
GPU_FORCE
)
{
respa_enable
=
0
;
cpu_time
=
0.0
;
GPU_EXTRA
::
gpu_ready
(
lmp
->
modify
,
lmp
->
error
);
}
/* ----------------------------------------------------------------------
free all arrays
------------------------------------------------------------------------- */
PairLJCutCoulLongGPU
::~
PairLJCutCoulLongGPU
()
{
ljcl_gpu_clear
();
}
/* ---------------------------------------------------------------------- */
void
PairLJCutCoulLongGPU
::
compute
(
int
eflag
,
int
vflag
)
{
if
(
eflag
||
vflag
)
ev_setup
(
eflag
,
vflag
);
else
evflag
=
vflag_fdotr
=
0
;
int
nall
=
atom
->
nlocal
+
atom
->
nghost
;
int
inum
,
host_start
;
bool
success
=
true
;
int
*
ilist
,
*
numneigh
,
**
firstneigh
;
if
(
gpu_mode
!=
GPU_FORCE
)
{
inum
=
atom
->
nlocal
;
firstneigh
=
ljcl_gpu_compute_n
(
neighbor
->
ago
,
inum
,
nall
,
atom
->
x
,
atom
->
type
,
domain
->
sublo
,
domain
->
subhi
,
atom
->
tag
,
atom
->
nspecial
,
atom
->
special
,
eflag
,
vflag
,
eflag_atom
,
vflag_atom
,
host_start
,
&
ilist
,
&
numneigh
,
cpu_time
,
success
,
atom
->
q
,
domain
->
boxlo
,
domain
->
prd
);
}
else
{
inum
=
list
->
inum
;
ilist
=
list
->
ilist
;
numneigh
=
list
->
numneigh
;
firstneigh
=
list
->
firstneigh
;
ljcl_gpu_compute
(
neighbor
->
ago
,
inum
,
nall
,
atom
->
x
,
atom
->
type
,
ilist
,
numneigh
,
firstneigh
,
eflag
,
vflag
,
eflag_atom
,
vflag_atom
,
host_start
,
cpu_time
,
success
,
atom
->
q
,
atom
->
nlocal
,
domain
->
boxlo
,
domain
->
prd
);
}
if
(
!
success
)
error
->
one
(
FLERR
,
"Insufficient memory on accelerator"
);
if
(
host_start
<
inum
)
{
cpu_time
=
MPI_Wtime
();
cpu_compute
(
host_start
,
inum
,
eflag
,
vflag
,
ilist
,
numneigh
,
firstneigh
);
cpu_time
=
MPI_Wtime
()
-
cpu_time
;
}
}
/* ----------------------------------------------------------------------
init specific to this pair style
------------------------------------------------------------------------- */
void
PairLJCutCoulLongGPU
::
init_style
()
{
cut_respa
=
NULL
;
if
(
!
atom
->
q_flag
)
error
->
all
(
FLERR
,
"Pair style lj/cut/coul/long/gpu requires atom attribute q"
);
if
(
force
->
newton_pair
)
error
->
all
(
FLERR
,
"Cannot use newton pair with lj/cut/coul/long/gpu pair style"
);
// Repeat cutsq calculation because done after call to init_style
double
maxcut
=
-
1.0
;
double
cut
;
for
(
int
i
=
1
;
i
<=
atom
->
ntypes
;
i
++
)
{
for
(
int
j
=
i
;
j
<=
atom
->
ntypes
;
j
++
)
{
if
(
setflag
[
i
][
j
]
!=
0
||
(
setflag
[
i
][
i
]
!=
0
&&
setflag
[
j
][
j
]
!=
0
))
{
cut
=
init_one
(
i
,
j
);
cut
*=
cut
;
if
(
cut
>
maxcut
)
maxcut
=
cut
;
cutsq
[
i
][
j
]
=
cutsq
[
j
][
i
]
=
cut
;
}
else
cutsq
[
i
][
j
]
=
cutsq
[
j
][
i
]
=
0.0
;
}
}
double
cell_size
=
sqrt
(
maxcut
)
+
neighbor
->
skin
;
cut_coulsq
=
cut_coul
*
cut_coul
;
// insure use of KSpace long-range solver, set g_ewald
if
(
force
->
kspace
==
NULL
)
error
->
all
(
FLERR
,
"Pair style requires a KSpace style"
);
g_ewald
=
force
->
kspace
->
g_ewald
;
// setup force tables
if
(
ncoultablebits
)
init_tables
(
cut_coul
,
cut_respa
);
int
maxspecial
=
0
;
if
(
atom
->
molecular
)
maxspecial
=
atom
->
maxspecial
;
int
success
=
ljcl_gpu_init
(
atom
->
ntypes
+
1
,
cutsq
,
lj1
,
lj2
,
lj3
,
lj4
,
offset
,
force
->
special_lj
,
atom
->
nlocal
,
atom
->
nlocal
+
atom
->
nghost
,
300
,
maxspecial
,
cell_size
,
gpu_mode
,
screen
,
cut_ljsq
,
cut_coulsq
,
force
->
special_coul
,
force
->
qqrd2e
,
g_ewald
);
GPU_EXTRA
::
check_flag
(
success
,
error
,
world
);
if
(
gpu_mode
==
GPU_FORCE
)
{
int
irequest
=
neighbor
->
request
(
this
,
instance_me
);
neighbor
->
requests
[
irequest
]
->
half
=
0
;
neighbor
->
requests
[
irequest
]
->
full
=
1
;
}
}
/* ---------------------------------------------------------------------- */
void
PairLJCutCoulLongGPU
::
reinit
()
{
Pair
::
reinit
();
ljcl_gpu_reinit
(
atom
->
ntypes
+
1
,
cutsq
,
lj1
,
lj2
,
lj3
,
lj4
,
offset
,
cut_ljsq
);
}
/* ---------------------------------------------------------------------- */
double
PairLJCutCoulLongGPU
::
memory_usage
()
{
double
bytes
=
Pair
::
memory_usage
();
return
bytes
+
ljcl_gpu_bytes
();
}
/* ---------------------------------------------------------------------- */
void
PairLJCutCoulLongGPU
::
cpu_compute
(
int
start
,
int
inum
,
int
eflag
,
int
vflag
,
int
*
ilist
,
int
*
numneigh
,
int
**
firstneigh
)
{
int
i
,
j
,
ii
,
jj
,
jnum
,
itype
,
jtype
,
itable
;
double
qtmp
,
xtmp
,
ytmp
,
ztmp
,
delx
,
dely
,
delz
,
evdwl
,
ecoul
,
fpair
;
double
fraction
,
table
;
double
r
,
r2inv
,
r6inv
,
forcecoul
,
forcelj
,
factor_coul
,
factor_lj
;
double
grij
,
expm2
,
prefactor
,
t
,
erfc
;
int
*
jlist
;
double
rsq
;
evdwl
=
ecoul
=
0.0
;
double
**
x
=
atom
->
x
;
double
**
f
=
atom
->
f
;
double
*
q
=
atom
->
q
;
int
*
type
=
atom
->
type
;
double
*
special_coul
=
force
->
special_coul
;
double
*
special_lj
=
force
->
special_lj
;
double
qqrd2e
=
force
->
qqrd2e
;
// loop over neighbors of my atoms
for
(
ii
=
start
;
ii
<
inum
;
ii
++
)
{
i
=
ilist
[
ii
];
qtmp
=
q
[
i
];
xtmp
=
x
[
i
][
0
];
ytmp
=
x
[
i
][
1
];
ztmp
=
x
[
i
][
2
];
itype
=
type
[
i
];
jlist
=
firstneigh
[
i
];
jnum
=
numneigh
[
i
];
for
(
jj
=
0
;
jj
<
jnum
;
jj
++
)
{
j
=
jlist
[
jj
];
factor_lj
=
special_lj
[
sbmask
(
j
)];
factor_coul
=
special_coul
[
sbmask
(
j
)];
j
&=
NEIGHMASK
;
delx
=
xtmp
-
x
[
j
][
0
];
dely
=
ytmp
-
x
[
j
][
1
];
delz
=
ztmp
-
x
[
j
][
2
];
rsq
=
delx
*
delx
+
dely
*
dely
+
delz
*
delz
;
jtype
=
type
[
j
];
if
(
rsq
<
cutsq
[
itype
][
jtype
])
{
r2inv
=
1.0
/
rsq
;
if
(
rsq
<
cut_coulsq
)
{
if
(
!
ncoultablebits
||
rsq
<=
tabinnersq
)
{
r
=
sqrt
(
rsq
);
grij
=
g_ewald
*
r
;
expm2
=
exp
(
-
grij
*
grij
);
t
=
1.0
/
(
1.0
+
EWALD_P
*
grij
);
erfc
=
t
*
(
A1
+
t
*
(
A2
+
t
*
(
A3
+
t
*
(
A4
+
t
*
A5
))))
*
expm2
;
prefactor
=
qqrd2e
*
qtmp
*
q
[
j
]
/
r
;
forcecoul
=
prefactor
*
(
erfc
+
EWALD_F
*
grij
*
expm2
);
if
(
factor_coul
<
1.0
)
forcecoul
-=
(
1.0
-
factor_coul
)
*
prefactor
;
}
else
{
union_int_float_t
rsq_lookup
;
rsq_lookup
.
f
=
rsq
;
itable
=
rsq_lookup
.
i
&
ncoulmask
;
itable
>>=
ncoulshiftbits
;
fraction
=
(
rsq_lookup
.
f
-
rtable
[
itable
])
*
drtable
[
itable
];
table
=
ftable
[
itable
]
+
fraction
*
dftable
[
itable
];
forcecoul
=
qtmp
*
q
[
j
]
*
table
;
if
(
factor_coul
<
1.0
)
{
table
=
ctable
[
itable
]
+
fraction
*
dctable
[
itable
];
prefactor
=
qtmp
*
q
[
j
]
*
table
;
forcecoul
-=
(
1.0
-
factor_coul
)
*
prefactor
;
}
}
}
else
forcecoul
=
0.0
;
if
(
rsq
<
cut_ljsq
[
itype
][
jtype
])
{
r6inv
=
r2inv
*
r2inv
*
r2inv
;
forcelj
=
r6inv
*
(
lj1
[
itype
][
jtype
]
*
r6inv
-
lj2
[
itype
][
jtype
]);
}
else
forcelj
=
0.0
;
fpair
=
(
forcecoul
+
factor_lj
*
forcelj
)
*
r2inv
;
f
[
i
][
0
]
+=
delx
*
fpair
;
f
[
i
][
1
]
+=
dely
*
fpair
;
f
[
i
][
2
]
+=
delz
*
fpair
;
if
(
eflag
)
{
if
(
rsq
<
cut_coulsq
)
{
if
(
!
ncoultablebits
||
rsq
<=
tabinnersq
)
ecoul
=
prefactor
*
erfc
;
else
{
table
=
etable
[
itable
]
+
fraction
*
detable
[
itable
];
ecoul
=
qtmp
*
q
[
j
]
*
table
;
}
if
(
factor_coul
<
1.0
)
ecoul
-=
(
1.0
-
factor_coul
)
*
prefactor
;
}
else
ecoul
=
0.0
;
if
(
rsq
<
cut_ljsq
[
itype
][
jtype
])
{
evdwl
=
r6inv
*
(
lj3
[
itype
][
jtype
]
*
r6inv
-
lj4
[
itype
][
jtype
])
-
offset
[
itype
][
jtype
];
evdwl
*=
factor_lj
;
}
else
evdwl
=
0.0
;
}
if
(
evflag
)
ev_tally_full
(
i
,
evdwl
,
ecoul
,
fpair
,
delx
,
dely
,
delz
);
}
}
}
}
Event Timeline
Log In to Comment