linux-sg2042/drivers/uwb/allocator.c

387 lines
9.9 KiB
C
Raw Normal View History

/*
* UWB reservation management.
*
* Copyright (C) 2008 Cambridge Silicon Radio Ltd.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include <linux/kernel.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/uwb.h>
#include "uwb-internal.h"
static void uwb_rsv_fill_column_alloc(struct uwb_rsv_alloc_info *ai)
{
int col, mas, safe_mas, unsafe_mas;
unsigned char *bm = ai->bm;
struct uwb_rsv_col_info *ci = ai->ci;
unsigned char c;
for (col = ci->csi.start_col; col < UWB_NUM_ZONES; col += ci->csi.interval) {
safe_mas = ci->csi.safe_mas_per_col;
unsafe_mas = ci->csi.unsafe_mas_per_col;
for (mas = 0; mas < UWB_MAS_PER_ZONE; mas++ ) {
if (bm[col * UWB_MAS_PER_ZONE + mas] == 0) {
if (safe_mas > 0) {
safe_mas--;
c = UWB_RSV_MAS_SAFE;
} else if (unsafe_mas > 0) {
unsafe_mas--;
c = UWB_RSV_MAS_UNSAFE;
} else {
break;
}
bm[col * UWB_MAS_PER_ZONE + mas] = c;
}
}
}
}
static void uwb_rsv_fill_row_alloc(struct uwb_rsv_alloc_info *ai)
{
int mas, col, rows;
unsigned char *bm = ai->bm;
struct uwb_rsv_row_info *ri = &ai->ri;
unsigned char c;
rows = 1;
c = UWB_RSV_MAS_SAFE;
for (mas = UWB_MAS_PER_ZONE - 1; mas >= 0; mas--) {
if (ri->avail[mas] == 1) {
if (rows > ri->used_rows) {
break;
} else if (rows > 7) {
c = UWB_RSV_MAS_UNSAFE;
}
for (col = 0; col < UWB_NUM_ZONES; col++) {
if (bm[col * UWB_NUM_ZONES + mas] != UWB_RSV_MAS_NOT_AVAIL) {
bm[col * UWB_NUM_ZONES + mas] = c;
if(c == UWB_RSV_MAS_SAFE)
ai->safe_allocated_mases++;
else
ai->unsafe_allocated_mases++;
}
}
rows++;
}
}
ai->total_allocated_mases = ai->safe_allocated_mases + ai->unsafe_allocated_mases;
}
/*
* Find the best column set for a given availability, interval, num safe mas and
* num unsafe mas.
*
* The different sets are tried in order as shown below, depending on the interval.
*
* interval = 16
* deep = 0
* set 1 -> { 8 }
* deep = 1
* set 1 -> { 4 }
* set 2 -> { 12 }
* deep = 2
* set 1 -> { 2 }
* set 2 -> { 6 }
* set 3 -> { 10 }
* set 4 -> { 14 }
* deep = 3
* set 1 -> { 1 }
* set 2 -> { 3 }
* set 3 -> { 5 }
* set 4 -> { 7 }
* set 5 -> { 9 }
* set 6 -> { 11 }
* set 7 -> { 13 }
* set 8 -> { 15 }
*
* interval = 8
* deep = 0
* set 1 -> { 4 12 }
* deep = 1
* set 1 -> { 2 10 }
* set 2 -> { 6 14 }
* deep = 2
* set 1 -> { 1 9 }
* set 2 -> { 3 11 }
* set 3 -> { 5 13 }
* set 4 -> { 7 15 }
*
* interval = 4
* deep = 0
* set 1 -> { 2 6 10 14 }
* deep = 1
* set 1 -> { 1 5 9 13 }
* set 2 -> { 3 7 11 15 }
*
* interval = 2
* deep = 0
* set 1 -> { 1 3 5 7 9 11 13 15 }
*/
static int uwb_rsv_find_best_column_set(struct uwb_rsv_alloc_info *ai, int interval,
int num_safe_mas, int num_unsafe_mas)
{
struct uwb_rsv_col_info *ci = ai->ci;
struct uwb_rsv_col_set_info *csi = &ci->csi;
struct uwb_rsv_col_set_info tmp_csi;
int deep, set, col, start_col_deep, col_start_set;
int start_col, max_mas_in_set, lowest_max_mas_in_deep;
int n_mas;
int found = UWB_RSV_ALLOC_NOT_FOUND;
tmp_csi.start_col = 0;
start_col_deep = interval;
n_mas = num_unsafe_mas + num_safe_mas;
for (deep = 0; ((interval >> deep) & 0x1) == 0; deep++) {
start_col_deep /= 2;
col_start_set = 0;
lowest_max_mas_in_deep = UWB_MAS_PER_ZONE;
for (set = 1; set <= (1 << deep); set++) {
max_mas_in_set = 0;
start_col = start_col_deep + col_start_set;
for (col = start_col; col < UWB_NUM_ZONES; col += interval) {
if (ci[col].max_avail_safe >= num_safe_mas &&
ci[col].max_avail_unsafe >= n_mas) {
if (ci[col].highest_mas[n_mas] > max_mas_in_set)
max_mas_in_set = ci[col].highest_mas[n_mas];
} else {
max_mas_in_set = 0;
break;
}
}
if ((lowest_max_mas_in_deep > max_mas_in_set) && max_mas_in_set) {
lowest_max_mas_in_deep = max_mas_in_set;
tmp_csi.start_col = start_col;
}
col_start_set += (interval >> deep);
}
if (lowest_max_mas_in_deep < 8) {
csi->start_col = tmp_csi.start_col;
found = UWB_RSV_ALLOC_FOUND;
break;
} else if ((lowest_max_mas_in_deep > 8) &&
(lowest_max_mas_in_deep != UWB_MAS_PER_ZONE) &&
(found == UWB_RSV_ALLOC_NOT_FOUND)) {
csi->start_col = tmp_csi.start_col;
found = UWB_RSV_ALLOC_FOUND;
}
}
if (found == UWB_RSV_ALLOC_FOUND) {
csi->interval = interval;
csi->safe_mas_per_col = num_safe_mas;
csi->unsafe_mas_per_col = num_unsafe_mas;
ai->safe_allocated_mases = (UWB_NUM_ZONES / interval) * num_safe_mas;
ai->unsafe_allocated_mases = (UWB_NUM_ZONES / interval) * num_unsafe_mas;
ai->total_allocated_mases = ai->safe_allocated_mases + ai->unsafe_allocated_mases;
ai->interval = interval;
}
return found;
}
static void get_row_descriptors(struct uwb_rsv_alloc_info *ai)
{
unsigned char *bm = ai->bm;
struct uwb_rsv_row_info *ri = &ai->ri;
int col, mas;
ri->free_rows = 16;
for (mas = 0; mas < UWB_MAS_PER_ZONE; mas ++) {
ri->avail[mas] = 1;
for (col = 1; col < UWB_NUM_ZONES; col++) {
if (bm[col * UWB_NUM_ZONES + mas] == UWB_RSV_MAS_NOT_AVAIL) {
ri->free_rows--;
ri->avail[mas]=0;
break;
}
}
}
}
static void uwb_rsv_fill_column_info(unsigned char *bm, int column, struct uwb_rsv_col_info *rci)
{
int mas;
int block_count = 0, start_block = 0;
int previous_avail = 0;
int available = 0;
int safe_mas_in_row[UWB_MAS_PER_ZONE] = {
8, 7, 6, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 2, 1,
};
rci->max_avail_safe = 0;
for (mas = 0; mas < UWB_MAS_PER_ZONE; mas ++) {
if (!bm[column * UWB_NUM_ZONES + mas]) {
available++;
rci->max_avail_unsafe = available;
rci->highest_mas[available] = mas;
if (previous_avail) {
block_count++;
if ((block_count > safe_mas_in_row[start_block]) &&
(!rci->max_avail_safe))
rci->max_avail_safe = available - 1;
} else {
previous_avail = 1;
start_block = mas;
block_count = 1;
}
} else {
previous_avail = 0;
}
}
if (!rci->max_avail_safe)
rci->max_avail_safe = rci->max_avail_unsafe;
}
static void get_column_descriptors(struct uwb_rsv_alloc_info *ai)
{
unsigned char *bm = ai->bm;
struct uwb_rsv_col_info *ci = ai->ci;
int col;
for (col = 1; col < UWB_NUM_ZONES; col++) {
uwb_rsv_fill_column_info(bm, col, &ci[col]);
}
}
static int uwb_rsv_find_best_row_alloc(struct uwb_rsv_alloc_info *ai)
{
int n_rows;
int max_rows = ai->max_mas / UWB_USABLE_MAS_PER_ROW;
int min_rows = ai->min_mas / UWB_USABLE_MAS_PER_ROW;
if (ai->min_mas % UWB_USABLE_MAS_PER_ROW)
min_rows++;
for (n_rows = max_rows; n_rows >= min_rows; n_rows--) {
if (n_rows <= ai->ri.free_rows) {
ai->ri.used_rows = n_rows;
ai->interval = 1; /* row reservation */
uwb_rsv_fill_row_alloc(ai);
return UWB_RSV_ALLOC_FOUND;
}
}
return UWB_RSV_ALLOC_NOT_FOUND;
}
static int uwb_rsv_find_best_col_alloc(struct uwb_rsv_alloc_info *ai, int interval)
{
int n_safe, n_unsafe, n_mas;
int n_column = UWB_NUM_ZONES / interval;
int max_per_zone = ai->max_mas / n_column;
int min_per_zone = ai->min_mas / n_column;
if (ai->min_mas % n_column)
min_per_zone++;
if (min_per_zone > UWB_MAS_PER_ZONE) {
return UWB_RSV_ALLOC_NOT_FOUND;
}
if (max_per_zone > UWB_MAS_PER_ZONE) {
max_per_zone = UWB_MAS_PER_ZONE;
}
for (n_mas = max_per_zone; n_mas >= min_per_zone; n_mas--) {
if (uwb_rsv_find_best_column_set(ai, interval, 0, n_mas) == UWB_RSV_ALLOC_NOT_FOUND)
continue;
for (n_safe = n_mas; n_safe >= 0; n_safe--) {
n_unsafe = n_mas - n_safe;
if (uwb_rsv_find_best_column_set(ai, interval, n_safe, n_unsafe) == UWB_RSV_ALLOC_FOUND) {
uwb_rsv_fill_column_alloc(ai);
return UWB_RSV_ALLOC_FOUND;
}
}
}
return UWB_RSV_ALLOC_NOT_FOUND;
}
int uwb_rsv_find_best_allocation(struct uwb_rsv *rsv, struct uwb_mas_bm *available,
struct uwb_mas_bm *result)
{
struct uwb_rsv_alloc_info *ai;
int interval;
int bit_index;
ai = kzalloc(sizeof(struct uwb_rsv_alloc_info), GFP_KERNEL);
ai->min_mas = rsv->min_mas;
ai->max_mas = rsv->max_mas;
ai->max_interval = rsv->max_interval;
/* fill the not available vector from the available bm */
for (bit_index = 0; bit_index < UWB_NUM_MAS; bit_index++) {
if (!test_bit(bit_index, available->bm))
ai->bm[bit_index] = UWB_RSV_MAS_NOT_AVAIL;
}
if (ai->max_interval == 1) {
get_row_descriptors(ai);
if (uwb_rsv_find_best_row_alloc(ai) == UWB_RSV_ALLOC_FOUND)
goto alloc_found;
else
goto alloc_not_found;
}
get_column_descriptors(ai);
for (interval = 16; interval >= 2; interval>>=1) {
if (interval > ai->max_interval)
continue;
if (uwb_rsv_find_best_col_alloc(ai, interval) == UWB_RSV_ALLOC_FOUND)
goto alloc_found;
}
/* try row reservation if no column is found */
get_row_descriptors(ai);
if (uwb_rsv_find_best_row_alloc(ai) == UWB_RSV_ALLOC_FOUND)
goto alloc_found;
else
goto alloc_not_found;
alloc_found:
bitmap_zero(result->bm, UWB_NUM_MAS);
bitmap_zero(result->unsafe_bm, UWB_NUM_MAS);
/* fill the safe and unsafe bitmaps */
for (bit_index = 0; bit_index < UWB_NUM_MAS; bit_index++) {
if (ai->bm[bit_index] == UWB_RSV_MAS_SAFE)
set_bit(bit_index, result->bm);
else if (ai->bm[bit_index] == UWB_RSV_MAS_UNSAFE)
set_bit(bit_index, result->unsafe_bm);
}
bitmap_or(result->bm, result->bm, result->unsafe_bm, UWB_NUM_MAS);
result->safe = ai->safe_allocated_mases;
result->unsafe = ai->unsafe_allocated_mases;
kfree(ai);
return UWB_RSV_ALLOC_FOUND;
alloc_not_found:
kfree(ai);
return UWB_RSV_ALLOC_NOT_FOUND;
}