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-rw-r--r--arch/tile/lib/spinlock_common.h64
1 files changed, 0 insertions, 64 deletions
diff --git a/arch/tile/lib/spinlock_common.h b/arch/tile/lib/spinlock_common.h
deleted file mode 100644
index 6ac37509faca..000000000000
--- a/arch/tile/lib/spinlock_common.h
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
- * Copyright 2010 Tilera Corporation. All Rights Reserved.
- *
- * 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, version 2.
- *
- * 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, GOOD TITLE or
- * NON INFRINGEMENT. See the GNU General Public License for
- * more details.
- * This file is included into spinlock_32.c or _64.c.
- */
-
-/*
- * The mfspr in __spinlock_relax() is 5 or 6 cycles plus 2 for loop
- * overhead.
- */
-#ifdef __tilegx__
-#define CYCLES_PER_RELAX_LOOP 7
-#else
-#define CYCLES_PER_RELAX_LOOP 8
-#endif
-
-/*
- * Idle the core for CYCLES_PER_RELAX_LOOP * iterations cycles.
- */
-static inline void
-relax(int iterations)
-{
- for (/*above*/; iterations > 0; iterations--)
- __insn_mfspr(SPR_PASS);
- barrier();
-}
-
-/* Perform bounded exponential backoff.*/
-static void delay_backoff(int iterations)
-{
- u32 exponent, loops;
-
- /*
- * 2^exponent is how many times we go around the loop,
- * which takes 8 cycles. We want to start with a 16- to 31-cycle
- * loop, so we need to go around minimum 2 = 2^1 times, so we
- * bias the original value up by 1.
- */
- exponent = iterations + 1;
-
- /*
- * Don't allow exponent to exceed 7, so we have 128 loops,
- * or 1,024 (to 2,047) cycles, as our maximum.
- */
- if (exponent > 8)
- exponent = 8;
-
- loops = 1 << exponent;
-
- /* Add a randomness factor so two cpus never get in lock step. */
- loops += __insn_crc32_32(stack_pointer, get_cycles_low()) &
- (loops - 1);
-
- relax(loops);
-}