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authorTejun Heo <tj@kernel.org>2012-04-01 12:30:01 -0700
committerTejun Heo <tj@kernel.org>2012-04-01 12:55:00 -0700
commit959d851caa48829eb85cb85aa949fd6b4c5d5bc6 (patch)
tree3ba9c94ec346275fb44c4f0d1cd2537cdff8d811 /lib/gen_crc32table.c
parenta5567932fc926739e29e98487128080f40c61710 (diff)
parent48ddbe194623ae089cc0576e60363f2d2e85662a (diff)
Merge branch 'for-3.5' of ../cgroup into block/for-3.5/core-merged
cgroup/for-3.5 contains the following changes which blk-cgroup needs to proceed with the on-going cleanup. * Dynamic addition and removal of cftypes to make config/stat file handling modular for policies. * cgroup removal update to not wait for css references to drain to fix blkcg removal hang caused by cfq caching cfqgs. Pull in cgroup/for-3.5 into block/for-3.5/core. This causes the following conflicts in block/blk-cgroup.c. * 761b3ef50e "cgroup: remove cgroup_subsys argument from callbacks" conflicts with blkiocg_pre_destroy() addition and blkiocg_attach() removal. Resolved by removing @subsys from all subsys methods. * 676f7c8f84 "cgroup: relocate cftype and cgroup_subsys definitions in controllers" conflicts with ->pre_destroy() and ->attach() updates and removal of modular config. Resolved by dropping forward declarations of the methods and applying updates to the relocated blkio_subsys. * 4baf6e3325 "cgroup: convert all non-memcg controllers to the new cftype interface" builds upon the previous item. Resolved by adding ->base_cftypes to the relocated blkio_subsys. Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'lib/gen_crc32table.c')
-rw-r--r--lib/gen_crc32table.c81
1 files changed, 61 insertions, 20 deletions
diff --git a/lib/gen_crc32table.c b/lib/gen_crc32table.c
index 85d0e412a04..8f8d5439e2d 100644
--- a/lib/gen_crc32table.c
+++ b/lib/gen_crc32table.c
@@ -1,14 +1,29 @@
#include <stdio.h>
+#include "../include/generated/autoconf.h"
#include "crc32defs.h"
#include <inttypes.h>
#define ENTRIES_PER_LINE 4
-#define LE_TABLE_SIZE (1 << CRC_LE_BITS)
-#define BE_TABLE_SIZE (1 << CRC_BE_BITS)
+#if CRC_LE_BITS > 8
+# define LE_TABLE_ROWS (CRC_LE_BITS/8)
+# define LE_TABLE_SIZE 256
+#else
+# define LE_TABLE_ROWS 1
+# define LE_TABLE_SIZE (1 << CRC_LE_BITS)
+#endif
-static uint32_t crc32table_le[4][LE_TABLE_SIZE];
-static uint32_t crc32table_be[4][BE_TABLE_SIZE];
+#if CRC_BE_BITS > 8
+# define BE_TABLE_ROWS (CRC_BE_BITS/8)
+# define BE_TABLE_SIZE 256
+#else
+# define BE_TABLE_ROWS 1
+# define BE_TABLE_SIZE (1 << CRC_BE_BITS)
+#endif
+
+static uint32_t crc32table_le[LE_TABLE_ROWS][256];
+static uint32_t crc32table_be[BE_TABLE_ROWS][256];
+static uint32_t crc32ctable_le[LE_TABLE_ROWS][256];
/**
* crc32init_le() - allocate and initialize LE table data
@@ -17,27 +32,38 @@ static uint32_t crc32table_be[4][BE_TABLE_SIZE];
* fact that crctable[i^j] = crctable[i] ^ crctable[j].
*
*/
-static void crc32init_le(void)
+static void crc32init_le_generic(const uint32_t polynomial,
+ uint32_t (*tab)[256])
{
unsigned i, j;
uint32_t crc = 1;
- crc32table_le[0][0] = 0;
+ tab[0][0] = 0;
- for (i = 1 << (CRC_LE_BITS - 1); i; i >>= 1) {
- crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);
+ for (i = LE_TABLE_SIZE >> 1; i; i >>= 1) {
+ crc = (crc >> 1) ^ ((crc & 1) ? polynomial : 0);
for (j = 0; j < LE_TABLE_SIZE; j += 2 * i)
- crc32table_le[0][i + j] = crc ^ crc32table_le[0][j];
+ tab[0][i + j] = crc ^ tab[0][j];
}
for (i = 0; i < LE_TABLE_SIZE; i++) {
- crc = crc32table_le[0][i];
- for (j = 1; j < 4; j++) {
- crc = crc32table_le[0][crc & 0xff] ^ (crc >> 8);
- crc32table_le[j][i] = crc;
+ crc = tab[0][i];
+ for (j = 1; j < LE_TABLE_ROWS; j++) {
+ crc = tab[0][crc & 0xff] ^ (crc >> 8);
+ tab[j][i] = crc;
}
}
}
+static void crc32init_le(void)
+{
+ crc32init_le_generic(CRCPOLY_LE, crc32table_le);
+}
+
+static void crc32cinit_le(void)
+{
+ crc32init_le_generic(CRC32C_POLY_LE, crc32ctable_le);
+}
+
/**
* crc32init_be() - allocate and initialize BE table data
*/
@@ -55,18 +81,18 @@ static void crc32init_be(void)
}
for (i = 0; i < BE_TABLE_SIZE; i++) {
crc = crc32table_be[0][i];
- for (j = 1; j < 4; j++) {
+ for (j = 1; j < BE_TABLE_ROWS; j++) {
crc = crc32table_be[0][(crc >> 24) & 0xff] ^ (crc << 8);
crc32table_be[j][i] = crc;
}
}
}
-static void output_table(uint32_t table[4][256], int len, char *trans)
+static void output_table(uint32_t (*table)[256], int rows, int len, char *trans)
{
int i, j;
- for (j = 0 ; j < 4; j++) {
+ for (j = 0 ; j < rows; j++) {
printf("{");
for (i = 0; i < len - 1; i++) {
if (i % ENTRIES_PER_LINE == 0)
@@ -83,15 +109,30 @@ int main(int argc, char** argv)
if (CRC_LE_BITS > 1) {
crc32init_le();
- printf("static const u32 crc32table_le[4][256] = {");
- output_table(crc32table_le, LE_TABLE_SIZE, "tole");
+ printf("static const u32 __cacheline_aligned "
+ "crc32table_le[%d][%d] = {",
+ LE_TABLE_ROWS, LE_TABLE_SIZE);
+ output_table(crc32table_le, LE_TABLE_ROWS,
+ LE_TABLE_SIZE, "tole");
printf("};\n");
}
if (CRC_BE_BITS > 1) {
crc32init_be();
- printf("static const u32 crc32table_be[4][256] = {");
- output_table(crc32table_be, BE_TABLE_SIZE, "tobe");
+ printf("static const u32 __cacheline_aligned "
+ "crc32table_be[%d][%d] = {",
+ BE_TABLE_ROWS, BE_TABLE_SIZE);
+ output_table(crc32table_be, LE_TABLE_ROWS,
+ BE_TABLE_SIZE, "tobe");
+ printf("};\n");
+ }
+ if (CRC_LE_BITS > 1) {
+ crc32cinit_le();
+ printf("static const u32 __cacheline_aligned "
+ "crc32ctable_le[%d][%d] = {",
+ LE_TABLE_ROWS, LE_TABLE_SIZE);
+ output_table(crc32ctable_le, LE_TABLE_ROWS,
+ LE_TABLE_SIZE, "tole");
printf("};\n");
}