Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
Showing
8 changed files
with
995 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,218 @@ | ||
| /* | ||
| * Copyright 2014 Jaidev Sridhar. | ||
| * Copyright 2014 Samy Al Bahra. | ||
| * All rights reserved. | ||
| * | ||
| * Redistribution and use in source and binary forms, with or without | ||
| * modification, are permitted provided that the following conditions | ||
| * are met: | ||
| * 1. Redistributions of source code must retain the above copyright | ||
| * notice, this list of conditions and the following disclaimer. | ||
| * 2. Redistributions in binary form must reproduce the above copyright | ||
| * notice, this list of conditions and the following disclaimer in the | ||
| * documentation and/or other materials provided with the distribution. | ||
| * | ||
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND | ||
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | ||
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE | ||
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | ||
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | ||
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | ||
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | ||
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | ||
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | ||
| * SUCH DAMAGE. | ||
| */ | ||
|
|
||
| #ifndef _CK_SWLOCK_H | ||
| #define _CK_SWLOCK_H | ||
|
|
||
| #include <ck_elide.h> | ||
| #include <ck_limits.h> | ||
| #include <ck_pr.h> | ||
| #include <stdbool.h> | ||
| #include <stddef.h> | ||
|
|
||
| struct ck_swlock { | ||
| uint32_t value; | ||
| }; | ||
| typedef struct ck_swlock ck_swlock_t; | ||
|
|
||
| #define CK_SWLOCK_INITIALIZER {0} | ||
| #define CK_SWLOCK_WRITER_BIT (1UL << 31) | ||
| #define CK_SWLOCK_LATCH_BIT (1UL << 30) | ||
| #define CK_SWLOCK_WRITER_MASK (CK_SWLOCK_LATCH_BIT | CK_SWLOCK_WRITER_BIT) | ||
| #define CK_SWLOCK_READER_MASK (UINT32_MAX ^ CK_SWLOCK_WRITER_MASK) | ||
|
|
||
| CK_CC_INLINE static void | ||
| ck_swlock_init(struct ck_swlock *rw) | ||
| { | ||
|
|
||
| rw->value = 0; | ||
| ck_pr_barrier(); | ||
| return; | ||
| } | ||
|
|
||
| CK_CC_INLINE static void | ||
| ck_swlock_write_unlock(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_fence_release(); | ||
| ck_pr_and_32(&rw->value, CK_SWLOCK_READER_MASK); | ||
| return; | ||
| } | ||
|
|
||
| CK_CC_INLINE static bool | ||
| ck_swlock_locked_writer(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_fence_load(); | ||
| return ck_pr_load_32(&rw->value) & CK_SWLOCK_WRITER_BIT; | ||
| } | ||
|
|
||
| CK_CC_INLINE static void | ||
| ck_swlock_write_downgrade(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_inc_32(&rw->value); | ||
| ck_swlock_write_unlock(rw); | ||
| return; | ||
| } | ||
|
|
||
| CK_CC_INLINE static bool | ||
| ck_swlock_locked(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_fence_load(); | ||
| return ck_pr_load_32(&rw->value); | ||
| } | ||
|
|
||
| CK_CC_INLINE static bool | ||
| ck_swlock_write_trylock(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_fence_acquire(); | ||
| return ck_pr_cas_32(&rw->value, 0, CK_SWLOCK_WRITER_BIT); | ||
| } | ||
|
|
||
| CK_ELIDE_TRYLOCK_PROTOTYPE(ck_swlock_write, ck_swlock_t, | ||
| ck_swlock_locked, ck_swlock_write_trylock) | ||
|
|
||
| CK_CC_INLINE static void | ||
| ck_swlock_write_lock(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_or_32(&rw->value, CK_SWLOCK_WRITER_BIT); | ||
| while (ck_pr_load_32(&rw->value) & CK_SWLOCK_READER_MASK) | ||
| ck_pr_stall(); | ||
|
|
||
| ck_pr_fence_acquire(); | ||
| return; | ||
| } | ||
|
|
||
| CK_CC_INLINE static void | ||
| ck_swlock_write_latch(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| /* Publish intent to acquire lock. */ | ||
| ck_pr_or_32(&rw->value, CK_SWLOCK_WRITER_BIT); | ||
|
|
||
| /* Stall until readers have seen the seen writer and cleared. */ | ||
| while (ck_pr_cas_32(&rw->value, CK_SWLOCK_WRITER_BIT, | ||
| CK_SWLOCK_WRITER_MASK) == false) { | ||
| do { | ||
| ck_pr_stall(); | ||
| } while (ck_pr_load_32(&rw->value) != CK_SWLOCK_WRITER_BIT); | ||
| } | ||
|
|
||
| ck_pr_fence_acquire(); | ||
| return; | ||
| } | ||
|
|
||
| CK_CC_INLINE static void | ||
| ck_swlock_write_unlatch(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_fence_release(); | ||
| ck_pr_store_32(&rw->value, 0); | ||
| return; | ||
| } | ||
|
|
||
| CK_ELIDE_PROTOTYPE(ck_swlock_write, ck_swlock_t, | ||
| ck_swlock_locked, ck_swlock_write_lock, | ||
| ck_swlock_locked_writer, ck_swlock_write_unlock) | ||
|
|
||
| CK_ELIDE_TRYLOCK_PROTOTYPE(ck_swlock_read, ck_swlock_t, | ||
| ck_swlock_locked_writer, ck_swlock_read_trylock) | ||
|
|
||
| CK_CC_INLINE static bool | ||
| ck_swlock_read_trylock(ck_swlock_t *rw) | ||
| { | ||
| uint32_t l = ck_pr_load_32(&rw->value); | ||
|
|
||
| if (l & CK_SWLOCK_WRITER_BIT) | ||
| return false; | ||
|
|
||
| l = ck_pr_faa_32(&rw->value, 1) & CK_SWLOCK_WRITER_MASK; | ||
| if (l == 0) { | ||
| ck_pr_fence_acquire(); | ||
| return true; | ||
| } | ||
|
|
||
| if (l == CK_SWLOCK_WRITER_BIT) | ||
| ck_pr_dec_32(&rw->value); | ||
|
|
||
| return false; | ||
| } | ||
|
|
||
| CK_CC_INLINE static void | ||
| ck_swlock_read_lock(ck_swlock_t *rw) | ||
| { | ||
| uint32_t l; | ||
|
|
||
| for (;;) { | ||
| while (ck_pr_load_32(&rw->value) & CK_SWLOCK_WRITER_BIT) | ||
| ck_pr_stall(); | ||
|
|
||
| l = ck_pr_faa_32(&rw->value, 1) & CK_SWLOCK_WRITER_MASK; | ||
| if (l == 0) | ||
| break; | ||
|
|
||
| /* | ||
| * If the latch bit has not been set, then the writer would | ||
| * have observed the reader and will wait to completion of | ||
| * read-side critical section. | ||
| */ | ||
| if (l == CK_SWLOCK_WRITER_BIT) | ||
| ck_pr_dec_32(&rw->value); | ||
| } | ||
|
|
||
| ck_pr_fence_acquire(); | ||
| return; | ||
| } | ||
|
|
||
|
|
||
| CK_CC_INLINE static bool | ||
| ck_swlock_locked_reader(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_fence_load(); | ||
| return ck_pr_load_32(&rw->value) & CK_SWLOCK_READER_MASK; | ||
| } | ||
|
|
||
| CK_CC_INLINE static void | ||
| ck_swlock_read_unlock(ck_swlock_t *rw) | ||
| { | ||
|
|
||
| ck_pr_fence_release(); | ||
| ck_pr_dec_32(&rw->value); | ||
| return; | ||
| } | ||
|
|
||
| CK_ELIDE_PROTOTYPE(ck_swlock_read, ck_swlock_t, | ||
| ck_swlock_locked_writer, ck_swlock_read_lock, | ||
| ck_swlock_locked_reader, ck_swlock_read_unlock) | ||
|
|
||
| #endif /* _CK_SWLOCK_H */ | ||
|
|
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,17 @@ | ||
| .PHONY: clean distribution | ||
|
|
||
| OBJECTS=latency throughput | ||
|
|
||
| all: $(OBJECTS) | ||
|
|
||
| latency: latency.c ../../../include/ck_swlock.h | ||
| $(CC) $(CFLAGS) -o latency latency.c | ||
|
|
||
| throughput: throughput.c ../../../include/ck_swlock.h | ||
| $(CC) $(CFLAGS) -o throughput throughput.c | ||
|
|
||
| clean: | ||
| rm -rf *.dSYM *.exe *~ *.o $(OBJECTS) | ||
|
|
||
| include ../../../build/regressions.build | ||
| CFLAGS+=$(PTHREAD_CFLAGS) -D_GNU_SOURCE |
Oops, something went wrong.