diff options
Diffstat (limited to 'sysdeps')
| -rw-r--r-- | sysdeps/generic/ldsodefs.h | 3 | ||||
| -rw-r--r-- | sysdeps/nacl/Makefile | 9 | ||||
| -rw-r--r-- | sysdeps/posix/opendir.c | 2 | ||||
| -rw-r--r-- | sysdeps/powerpc/nptl/elide.h | 115 | ||||
| -rw-r--r-- | sysdeps/sparc/sparc32/sem_open.c | 1 |
5 files changed, 74 insertions, 56 deletions
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index 7a0fe8dbe4..78e3a97c06 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -592,9 +592,6 @@ struct rtld_global_ro /* List of auditing interfaces. */ struct audit_ifaces *_dl_audit; unsigned int _dl_naudit; - - /* 0 if internal pointer values should not be guarded, 1 if they should. */ - EXTERN int _dl_pointer_guard; }; # define __rtld_global_attribute__ # if IS_IN (rtld) diff --git a/sysdeps/nacl/Makefile b/sysdeps/nacl/Makefile index 6749a44c53..1748886719 100644 --- a/sysdeps/nacl/Makefile +++ b/sysdeps/nacl/Makefile @@ -132,4 +132,13 @@ ifeq ($(subdir),misc) # sysdeps/.../linux/ directories, but it's still a sysdeps decision to # install it. sysdep_headers += bits/mman-linux.h + +# This defeats sysdeps/gnu/Makefile's addition of sys/mtio.h, which +# we do not want. This is a total kludge, but it seems no worse for +# now than making the sysdeps/gnu/Makefile code conditional on a +# variable we set here. If some sysdeps/.../Makefile that is later +# in the list than sysdeps/gnu needed to add to sysdep_headers, this +# would break it. But sysdeps/gnu is close to last in the list and +# this coming up seems unlikely. +override sysdep_headers := $(sysdep_headers) endif diff --git a/sysdeps/posix/opendir.c b/sysdeps/posix/opendir.c index 6509f5c05c..9edf056fb3 100644 --- a/sysdeps/posix/opendir.c +++ b/sysdeps/posix/opendir.c @@ -105,7 +105,7 @@ need_isdir_precheck (void) tryopen_o_directory (); /* We can skip the expensive `stat' call if O_DIRECTORY works. */ - return o_directory_works > 0; + return o_directory_works < 0; #endif return true; } diff --git a/sysdeps/powerpc/nptl/elide.h b/sysdeps/powerpc/nptl/elide.h index 389f5a5e9e..12171f45dc 100644 --- a/sysdeps/powerpc/nptl/elide.h +++ b/sysdeps/powerpc/nptl/elide.h @@ -23,67 +23,78 @@ # include <htm.h> # include <elision-conf.h> -/* Returns true if the lock defined by is_lock_free as elided. - ADAPT_COUNT is a pointer to per-lock state variable. */ - +/* Get the new value of adapt_count according to the elision + configurations. Returns true if the system should retry again or false + otherwise. */ static inline bool -__elide_lock (uint8_t *adapt_count, int is_lock_free) +__get_new_count (uint8_t *adapt_count) { - if (*adapt_count > 0) + /* A persistent failure indicates that a retry will probably + result in another failure. Use normal locking now and + for the next couple of calls. */ + if (_TEXASRU_FAILURE_PERSISTENT (__builtin_get_texasru ())) { - (*adapt_count)--; + if (__elision_aconf.skip_lock_internal_abort > 0) + *adapt_count = __elision_aconf.skip_lock_internal_abort; return false; } - - for (int i = __elision_aconf.try_tbegin; i > 0; i--) - { - if (__builtin_tbegin (0)) - { - if (is_lock_free) - return true; - /* Lock was busy. */ - __builtin_tabort (_ABORT_LOCK_BUSY); - } - else - { - /* A persistent failure indicates that a retry will probably - result in another failure. Use normal locking now and - for the next couple of calls. */ - if (_TEXASRU_FAILURE_PERSISTENT (__builtin_get_texasru ())) - { - if (__elision_aconf.skip_lock_internal_abort > 0) - *adapt_count = __elision_aconf.skip_lock_internal_abort; - break; - } - /* Same logic as above, but for a number of temporary failures in a - a row. */ - else if (__elision_aconf.skip_lock_out_of_tbegin_retries > 0 - && __elision_aconf.try_tbegin > 0) - *adapt_count = __elision_aconf.skip_lock_out_of_tbegin_retries; - } - } - - return false; + /* Same logic as above, but for a number of temporary failures in a + a row. */ + else if (__elision_aconf.skip_lock_out_of_tbegin_retries > 0 + && __elision_aconf.try_tbegin > 0) + *adapt_count = __elision_aconf.skip_lock_out_of_tbegin_retries; + return true; } -# define ELIDE_LOCK(adapt_count, is_lock_free) \ - __elide_lock (&(adapt_count), is_lock_free) - - -static inline bool -__elide_trylock (uint8_t *adapt_count, int is_lock_free, int write) -{ - if (__elision_aconf.try_tbegin > 0) - { - if (write) - __builtin_tabort (_ABORT_NESTED_TRYLOCK); - return __elide_lock (adapt_count, is_lock_free); - } - return false; -} +/* CONCURRENCY NOTES: + + The evaluation of the macro expression is_lock_free encompasses one or + more loads from memory locations that are concurrently modified by other + threads. For lock elision to work, this evaluation and the rest of the + critical section protected by the lock must be atomic because an + execution with lock elision must be equivalent to an execution in which + the lock would have been actually acquired and released. Therefore, we + evaluate is_lock_free inside of the transaction that represents the + critical section for which we want to use lock elision, which ensures + the atomicity that we require. */ + +/* Returns 0 if the lock defined by is_lock_free was elided. + ADAPT_COUNT is a per-lock state variable. */ +# define ELIDE_LOCK(adapt_count, is_lock_free) \ + ({ \ + int ret = 0; \ + if (adapt_count > 0) \ + (adapt_count)--; \ + else \ + for (int i = __elision_aconf.try_tbegin; i > 0; i--) \ + { \ + if (__builtin_tbegin (0)) \ + { \ + if (is_lock_free) \ + { \ + ret = 1; \ + break; \ + } \ + __builtin_tabort (_ABORT_LOCK_BUSY); \ + } \ + else \ + if (!__get_new_count(&adapt_count)) \ + break; \ + } \ + ret; \ + }) # define ELIDE_TRYLOCK(adapt_count, is_lock_free, write) \ - __elide_trylock (&(adapt_count), is_lock_free, write) + ({ \ + int ret = 0; \ + if (__elision_aconf.try_tbegin > 0) \ + { \ + if (write) \ + __builtin_tabort (_ABORT_NESTED_TRYLOCK); \ + ret = ELIDE_LOCK (adapt_count, is_lock_free); \ + } \ + ret; \ + }) static inline bool diff --git a/sysdeps/sparc/sparc32/sem_open.c b/sysdeps/sparc/sparc32/sem_open.c index 16cb9ad591..59df2d7b9b 100644 --- a/sysdeps/sparc/sparc32/sem_open.c +++ b/sysdeps/sparc/sparc32/sem_open.c @@ -29,6 +29,7 @@ #include <sys/mman.h> #include <sys/stat.h> #include "semaphoreP.h" +#include <futex-internal.h> #include <shm-directory.h> |