Changes in / [0519e34:b2a11ba]


Ignore:
Files:
1 deleted
8 edited

Legend:

Unmodified
Added
Removed

  • libcfa/configure.ac

    r0519e34 rb2a11ba  
    166166AH_TEMPLATE([CFA_HAVE_IORING_OP_PROVIDE_BUFFERS],[Defined if io_uring support is present when compiling libcfathread and supports the operation IORING_OP_PROVIDE_BUFFERS.])
    167167AH_TEMPLATE([CFA_HAVE_IORING_OP_REMOVE_BUFFER],[Defined if io_uring support is present when compiling libcfathread and supports the operation IORING_OP_REMOVE_BUFFER.])
    168 AH_TEMPLATE([CFA_HAVE_IORING_OP_TEE],[Defined if io_uring support is present when compiling libcfathread and supports the operation IORING_OP_TEE.])
    169168AH_TEMPLATE([CFA_HAVE_IOSQE_FIXED_FILE],[Defined if io_uring support is present when compiling libcfathread and supports the flag FIXED_FILE.])
    170169AH_TEMPLATE([CFA_HAVE_IOSQE_IO_DRAIN],[Defined if io_uring support is present when compiling libcfathread and supports the flag IO_DRAIN.])
    … …  
    174173AH_TEMPLATE([CFA_HAVE_SPLICE_F_FD_IN_FIXED],[Defined if io_uring support is present when compiling libcfathread and supports the flag SPLICE_F_FD_IN_FIXED.])
    175174AH_TEMPLATE([CFA_HAVE_IORING_SETUP_ATTACH_WQ],[Defined if io_uring support is present when compiling libcfathread and supports the flag IORING_SETUP_ATTACH_WQ.])
    176 AH_TEMPLATE([CFA_HAVE_PREADV2],[Defined if preadv2 support is present when compiling libcfathread.])
    177 AH_TEMPLATE([CFA_HAVE_PWRITEV2],[Defined if pwritev2 support is present when compiling libcfathread.])
    178 AH_TEMPLATE([CFA_HAVE_PWRITEV2],[Defined if pwritev2 support is present when compiling libcfathread.])
    179 AH_TEMPLATE([CFA_HAVE_STATX],[Defined if statx support is present when compiling libcfathread.])
    180 AH_TEMPLATE([CFA_HAVE_OPENAT2],[Defined if openat2 support is present when compiling libcfathread.])
     175AH_TEMPLATE([HAVE_PREADV2],[Defined if preadv2 support is present when compiling libcfathread.])
     176AH_TEMPLATE([HAVE_PWRITEV2],[Defined if pwritev2 support is present when compiling libcfathread.])
    181177AH_TEMPLATE([__CFA_NO_STATISTICS__],[Defined if libcfathread was compiled without support for statistics.])
    182178
    183 define(ioring_ops, [IORING_OP_NOP,IORING_OP_READV,IORING_OP_WRITEV,IORING_OP_FSYNC,IORING_OP_READ_FIXED,IORING_OP_WRITE_FIXED,IORING_OP_POLL_ADD,IORING_OP_POLL_REMOVE,IORING_OP_SYNC_FILE_RANGE,IORING_OP_SENDMSG,IORING_OP_RECVMSG,IORING_OP_TIMEOUT,IORING_OP_TIMEOUT_REMOVE,IORING_OP_ACCEPT,IORING_OP_ASYNC_CANCEL,IORING_OP_LINK_TIMEOUT,IORING_OP_CONNECT,IORING_OP_FALLOCATE,IORING_OP_OPENAT,IORING_OP_CLOSE,IORING_OP_FILES_UPDATE,IORING_OP_STATX,IORING_OP_READ,IORING_OP_WRITE,IORING_OP_FADVISE,IORING_OP_MADVISE,IORING_OP_SEND,IORING_OP_RECV,IORING_OP_OPENAT2,IORING_OP_EPOLL_CTL,IORING_OP_SPLICE,IORING_OP_PROVIDE_BUFFERS,IORING_OP_REMOVE_BUFFER,IORING_OP_TEE])
     179define(ioring_ops, [IORING_OP_NOP,IORING_OP_READV,IORING_OP_WRITEV,IORING_OP_FSYNC,IORING_OP_READ_FIXED,IORING_OP_WRITE_FIXED,IORING_OP_POLL_ADD,IORING_OP_POLL_REMOVE,IORING_OP_SYNC_FILE_RANGE,IORING_OP_SENDMSG,IORING_OP_RECVMSG,IORING_OP_TIMEOUT,IORING_OP_TIMEOUT_REMOVE,IORING_OP_ACCEPT,IORING_OP_ASYNC_CANCEL,IORING_OP_LINK_TIMEOUT,IORING_OP_CONNECT,IORING_OP_FALLOCATE,IORING_OP_OPENAT,IORING_OP_CLOSE,IORING_OP_FILES_UPDATE,IORING_OP_STATX,IORING_OP_READ,IORING_OP_WRITE,IORING_OP_FADVISE,IORING_OP_MADVISE,IORING_OP_SEND,IORING_OP_RECV,IORING_OP_OPENAT2,IORING_OP_EPOLL_CTL,IORING_OP_SPLICE,IORING_OP_PROVIDE_BUFFERS,IORING_OP_REMOVE_BUFFER])
    184180define(ioring_flags, [IOSQE_FIXED_FILE,IOSQE_IO_DRAIN,IOSQE_ASYNC,IOSQE_IO_LINK,IOSQE_IO_HARDLINK,SPLICE_F_FD_IN_FIXED,IORING_SETUP_ATTACH_WQ])
    185181
    … …  
    226222        ])
    227223])
    228 AC_CHECK_FUNC([preadv2], [AC_DEFINE([CFA_HAVE_PREADV2])])
    229 AC_CHECK_FUNC([pwritev2], [AC_DEFINE([CFA_HAVE_PWRITEV2])])
     224AC_CHECK_FUNCS([preadv2 pwritev2])
    230225
    231226AC_CONFIG_FILES([
    … …  
    234229        prelude/Makefile
    235230        ])
    236 AC_CONFIG_FILES([src/concurrency/io/call.cfa], [python3 ${srcdir}/src/concurrency/io/call.cfa.in > src/concurrency/io/call.cfa])
    237231
    238232AC_CONFIG_HEADERS(prelude/defines.hfa)

  • libcfa/prelude/defines.hfa.in

    r0519e34 rb2a11ba  
    117117
    118118/* Defined if io_uring support is present when compiling libcfathread and
    119    supports the operation IORING_OP_TEE. */
    120 #undef CFA_HAVE_IORING_OP_TEE
    121 
    122 /* Defined if io_uring support is present when compiling libcfathread and
    123119   supports the operation IORING_OP_TIMEOUT. */
    124120#undef CFA_HAVE_IORING_OP_TIMEOUT
    … …  
    167163#undef CFA_HAVE_LINUX_IO_URING_H
    168164
    169 /* Defined if openat2 support is present when compiling libcfathread. */
    170 #undef CFA_HAVE_OPENAT2
    171 
    172 /* Defined if preadv2 support is present when compiling libcfathread. */
    173 #undef CFA_HAVE_PREADV2
    174 
    175 /* Defined if pwritev2 support is present when compiling libcfathread. */
    176 #undef CFA_HAVE_PWRITEV2
    177 
    178165/* Defined if io_uring support is present when compiling libcfathread and
    179166   supports the flag SPLICE_F_FD_IN_FIXED. */
    180167#undef CFA_HAVE_SPLICE_F_FD_IN_FIXED
    181168
    182 /* Defined if statx support is present when compiling libcfathread. */
    183 #undef CFA_HAVE_STATX
    184 
    185169/* Location of include files. */
    186170#undef CFA_INCDIR
    … …  
    204188#undef HAVE_MEMORY_H
    205189
     190/* Define to 1 if you have the `preadv2' function. */
     191#undef HAVE_PREADV2
     192
     193/* Define to 1 if you have the `pwritev2' function. */
     194#undef HAVE_PWRITEV2
     195
    206196/* Define to 1 if you have the <stdint.h> header file. */
    207197#undef HAVE_STDINT_H

  • libcfa/src/Makefile.am

    r0519e34 rb2a11ba  
    108108        concurrency/io/setup.cfa \
    109109        concurrency/io/types.hfa \
    110         concurrency/io/call.cfa \
     110        concurrency/iocall.cfa \
    111111        concurrency/iofwd.hfa \
    112112        concurrency/kernel_private.hfa \

  • libcfa/src/concurrency/io.cfa

    r0519e34 rb2a11ba  
    159159
    160160        static inline void process(struct io_uring_cqe & cqe ) {
    161                 struct io_future_t * future = (struct io_future_t *)(uintptr_t)cqe.user_data;
    162                 __cfadbg_print_safe( io, "Kernel I/O : Syscall completed : cqe %p, result %d for %p\n", future, cqe.res, data->thrd );
    163 
    164                 fulfil( *future, cqe.res );
     161                struct __io_user_data_t * data = (struct __io_user_data_t *)(uintptr_t)cqe.user_data;
     162                __cfadbg_print_safe( io, "Kernel I/O : Syscall completed : cqe %p, result %d for %p\n", data, cqe.res, data->thrd );
     163
     164                data->result = cqe.res;
     165                post( data->sem );
    165166        }
    166167

  • libcfa/src/concurrency/io/types.hfa

    r0519e34 rb2a11ba  
    104104        //-----------------------------------------------------------------------
    105105        // IO user data
    106         struct io_future_t {
    107                 future_t self;
     106        struct __io_user_data_t {
    108107                __s32 result;
     108                oneshot sem;
    109109        };
    110 
    111         static inline {
    112                 bool fulfil( io_future_t & this, __s32 result ) {
    113                         this.result = result;
    114                         return fulfil(this.self);
    115                 }
    116 
    117                 // Wait for the future to be fulfilled
    118                 bool wait( io_future_t & this ) {
    119                         return wait(this.self);
    120                 }
    121         }
    122110
    123111        //-----------------------------------------------------------------------

  • libcfa/src/concurrency/iofwd.hfa

    r0519e34 rb2a11ba  
    4040
    4141struct cluster;
    42 struct io_future_t;
    4342struct io_context;
    4443struct io_cancellation;
    … …  
    4948struct statx;
    5049
    51 //----------
    52 // synchronous calls
    53 #if defined(CFA_HAVE_PREADV2)
    54         extern ssize_t cfa_preadv2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    55 #endif
    56 #if defined(CFA_HAVE_PWRITEV2)
    57         extern ssize_t cfa_pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    58 #endif
    59 extern int cfa_fsync(int fd, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    60 extern int cfa_epoll_ctl(int epfd, int op, int fd, struct epoll_event *event, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    61 extern int cfa_sync_file_range(int fd, off64_t offset, off64_t nbytes, unsigned int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    62 extern  ssize_t cfa_sendmsg(int sockfd, const struct msghdr *msg, int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    63 extern ssize_t cfa_recvmsg(int sockfd, struct msghdr *msg, int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    64 extern ssize_t cfa_send(int sockfd, const void *buf, size_t len, int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    65 extern ssize_t cfa_recv(int sockfd, void *buf, size_t len, int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    66 extern int cfa_accept4(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    67 extern int cfa_connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    68 extern int cfa_fallocate(int fd, int mode, off_t offset, off_t len, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    69 extern int cfa_posix_fadvise(int fd, off_t offset, off_t len, int advice, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    70 extern int cfa_madvise(void *addr, size_t length, int advice, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    71 extern int cfa_openat(int dirfd, const char *pathname, int flags, mode_t mode, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    72 #if defined(CFA_HAVE_OPENAT2)
    73         extern int cfa_openat2(int dirfd, const char *pathname, struct open_how * how, size_t size, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    74 #endif
    75 extern int cfa_close(int fd, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    76 #if defined(CFA_HAVE_STATX)
    77         extern int cfa_statx(int dirfd, const char *pathname, int flags, unsigned int mask, struct statx *statxbuf, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    78 #endif
    79 extern ssize_t cfa_read(int fd, void * buf, size_t count, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    80 extern ssize_t cfa_write(int fd, void * buf, size_t count, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    81 extern ssize_t cfa_splice(int fd_in, loff_t *off_in, int fd_out, loff_t *off_out, size_t len, unsigned int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    82 extern ssize_t cfa_tee(int fd_in, int fd_out, size_t len, unsigned int flags, int submit_flags, Duration timeout, io_cancellation * cancellation, io_context * context);
    83 
    84 //----------
    85 // asynchronous calls
    86 #if defined(CFA_HAVE_PREADV2)
    87         extern void async_preadv2(io_future_t & future, int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    88 #endif
    89 #if defined(CFA_HAVE_PWRITEV2)
    90         extern void async_pwritev2(io_future_t & future, int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    91 #endif
    92 extern void async_fsync(io_future_t & future, int fd, int submit_flags, io_cancellation * cancellation, io_context * context);
    93 extern void async_epoll_ctl(io_future_t & future, int epfd, int op, int fd, struct epoll_event *event, int submit_flags, io_cancellation * cancellation, io_context * context);
    94 extern void async_sync_file_range(io_future_t & future, int fd, off64_t offset, off64_t nbytes, unsigned int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    95 extern void async_sendmsg(io_future_t & future, int sockfd, const struct msghdr *msg, int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    96 extern void async_recvmsg(io_future_t & future, int sockfd, struct msghdr *msg, int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    97 extern void async_send(io_future_t & future, int sockfd, const void *buf, size_t len, int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    98 extern void async_recv(io_future_t & future, int sockfd, void *buf, size_t len, int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    99 extern void async_accept4(io_future_t & future, int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    100 extern void async_connect(io_future_t & future, int sockfd, const struct sockaddr *addr, socklen_t addrlen, int submit_flags, io_cancellation * cancellation, io_context * context);
    101 extern void async_fallocate(io_future_t & future, int fd, int mode, off_t offset, off_t len, int submit_flags, io_cancellation * cancellation, io_context * context);
    102 extern void async_posix_fadvise(io_future_t & future, int fd, off_t offset, off_t len, int advice, int submit_flags, io_cancellation * cancellation, io_context * context);
    103 extern void async_madvise(io_future_t & future, void *addr, size_t length, int advice, int submit_flags, io_cancellation * cancellation, io_context * context);
    104 extern void async_openat(io_future_t & future, int dirfd, const char *pathname, int flags, mode_t mode, int submit_flags, io_cancellation * cancellation, io_context * context);
    105 #if defined(CFA_HAVE_OPENAT2)
    106         extern void async_openat2(io_future_t & future, int dirfd, const char *pathname, struct open_how * how, size_t size, int submit_flags, io_cancellation * cancellation, io_context * context);
    107 #endif
    108 extern void async_close(io_future_t & future, int fd, int submit_flags, io_cancellation * cancellation, io_context * context);
    109 #if defined(CFA_HAVE_STATX)
    110         extern void async_statx(io_future_t & future, int dirfd, const char *pathname, int flags, unsigned int mask, struct statx *statxbuf, int submit_flags, io_cancellation * cancellation, io_context * context);
    111 #endif
    112 void async_read(io_future_t & future, int fd, void * buf, size_t count, int submit_flags, io_cancellation * cancellation, io_context * context);
    113 extern void async_write(io_future_t & future, int fd, void * buf, size_t count, int submit_flags, io_cancellation * cancellation, io_context * context);
    114 extern void async_splice(io_future_t & future, int fd_in, loff_t *off_in, int fd_out, loff_t *off_out, size_t len, unsigned int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    115 extern void async_tee(io_future_t & future, int fd_in, int fd_out, size_t len, unsigned int flags, int submit_flags, io_cancellation * cancellation, io_context * context);
    116 
     50extern ssize_t cfa_preadv2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     51extern ssize_t cfa_pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     52extern int cfa_fsync(int fd, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     53extern int cfa_sync_file_range(int fd, int64_t offset, int64_t nbytes, unsigned int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     54extern ssize_t cfa_sendmsg(int sockfd, const struct msghdr *msg, int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     55extern ssize_t cfa_recvmsg(int sockfd, struct msghdr *msg, int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     56extern ssize_t cfa_send(int sockfd, const void *buf, size_t len, int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     57extern ssize_t cfa_recv(int sockfd, void *buf, size_t len, int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     58extern int cfa_accept4(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     59extern int cfa_connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     60extern int cfa_fallocate(int fd, int mode, uint64_t offset, uint64_t len, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     61extern int cfa_fadvise(int fd, uint64_t offset, uint64_t len, int advice, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     62extern int cfa_madvise(void *addr, size_t length, int advice, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     63extern int cfa_openat(int dirfd, const char *pathname, int flags, mode_t mode, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     64extern int cfa_close(int fd, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     65extern int cfa_statx(int dirfd, const char *pathname, int flags, unsigned int mask, struct statx *statxbuf, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     66extern ssize_t cfa_read(int fd, void *buf, size_t count, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     67extern ssize_t cfa_write(int fd, void *buf, size_t count, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     68extern ssize_t cfa_splice(int fd_in, loff_t *off_in, int fd_out, loff_t *off_out, size_t len, unsigned int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
     69extern ssize_t cfa_tee(int fd_in, int fd_out, size_t len, unsigned int flags, int submit_flags = 0, Duration timeout = -1`s, io_cancellation * cancellation = 0p, io_context * context = 0p);
    11770
    11871//-----------------------------------------------------------------------------

  • libcfa/src/concurrency/kernel.hfa

    r0519e34 rb2a11ba  
    2323
    2424extern "C" {
    25         #include <bits/pthreadtypes.h>
    26         #include <linux/types.h>
     25#include <bits/pthreadtypes.h>
    2726}
    2827
    … …  
    158157
    159158struct io_cancellation {
    160         __u64 target;
     159        uint32_t target;
    161160};
    162161

  • tests/Makefile.am

    r0519e34 rb2a11ba  
    6060# adjusted CC but without the actual distcc call
    6161CFACCLOCAL = $(if $(DISTCC_CFA_PATH),$(DISTCC_CFA_PATH) ${ARCH_FLAGS},$(TARGET_CFA) ${DEBUG_FLAGS} ${ARCH_FLAGS})
    62 CFACCLINK = $(CFACCLOCAL) $(if $(test), 2> $(test), ) $($(shell echo "${@}_FLAGSLD" | sed 's/-\|\//_/g'))
    6362
    6463PRETTY_PATH=mkdir -p $(dir $(abspath ${@})) && cd ${srcdir} &&
    … …  
    113112% : %.cfa $(CFACCBIN)
    114113        $(CFACOMPILETEST) -c -o $(abspath ${@}).o
    115         $(CFACCLINK) ${@}.o -o $(abspath ${@})
     114        $(CFACCLOCAL) -quiet $(if $(test), 2> $(test), ) $($(shell echo "${@}_FLAGSLD" | sed 's/-\|\//_/g')) ${@}.o -o $(abspath ${@})
    116115        rm $(abspath ${@}).o
    117116
    … …  
    178177        $(CFACCLOCAL) $($(shell echo "${@}_FLAGSLD" | sed 's/-\|\//_/g')) $(abspath ${@}).o -o $(abspath ${@})
    179178
    180 # Linking tests
    181 # Meta tests to make sure we see linking errors (can't compile with -O2 since it may multiply number of calls)
    182 linking/linkerror : linking/linkerror.cfa $(CFACCBIN)
    183         $(CFACOMPILETEST) -O0 -c -o $(abspath ${@}).o
    184         $(CFACCLINK)  -O0 ${@}.o -o $(abspath ${@})
    185         rm $(abspath ${@}).o
    186 
    187179#------------------------------------------------------------------------------
    188180# Other targets
Note: See TracChangeset for help on using the changeset viewer.