From a364a3a7090b82ddd30e9209df2af56e781d51e4 Mon Sep 17 00:00:00 2001 From: Wilco Dijkstra Date: Fri, 9 Sep 2022 14:22:26 +0100 Subject: [PATCH] Use C11 atomics instead of atomic_decrement(_val) Replace atomic_decrement and atomic_decrement_val with atomic_fetch_add_relaxed. Reviewed-by: DJ Delorie --- htl/pt-create.c | 2 +- malloc/malloc.c | 2 +- manual/ipc.texi | 2 +- manual/llio.texi | 2 +- nptl/nptl_setxid.c | 2 +- nptl/pthread_create.c | 2 +- nscd/nscd-client.h | 2 +- nscd/nscd_getai.c | 2 +- nscd/nscd_getgr_r.c | 2 +- nscd/nscd_gethst_r.c | 2 +- nscd/nscd_getpw_r.c | 2 +- nscd/nscd_getserv_r.c | 2 +- nscd/nscd_helper.c | 2 +- nscd/nscd_initgroups.c | 2 +- nscd/nscd_netgroup.c | 4 ++-- 15 files changed, 16 insertions(+), 16 deletions(-) diff --git a/htl/pt-create.c b/htl/pt-create.c index ce52ed9..36f138b 100644 --- a/htl/pt-create.c +++ b/htl/pt-create.c @@ -262,7 +262,7 @@ failed_starting: } __pthread_setid (pthread->thread, NULL); - atomic_decrement (&__pthread_total); + atomic_fetch_add_relaxed (&__pthread_total, -1); failed_sigstate: __pthread_sigstate_destroy (pthread); failed_setup: diff --git a/malloc/malloc.c b/malloc/malloc.c index aea4993..bfe1955 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -3033,7 +3033,7 @@ munmap_chunk (mchunkptr p) || __glibc_unlikely (!powerof2 (mem & (pagesize - 1)))) malloc_printerr ("munmap_chunk(): invalid pointer"); - atomic_decrement (&mp_.n_mmaps); + atomic_fetch_add_relaxed (&mp_.n_mmaps, -1); atomic_fetch_add_relaxed (&mp_.mmapped_mem, -total_size); /* If munmap failed the process virtual memory address space is in a diff --git a/manual/ipc.texi b/manual/ipc.texi index 081b98f..46c049c 100644 --- a/manual/ipc.texi +++ b/manual/ipc.texi @@ -89,7 +89,7 @@ by @theglibc{}. @c @c Given the use atomic operations this function seems @c to be AS-safe. It is AC-unsafe because there is still -@c a window between atomic_decrement and the pthread_push +@c a window between atomic_fetch_add_relaxed and the pthread_push @c of the handler that undoes that operation. A cancellation @c at that point would fail to remove the process from the @c waiters count. diff --git a/manual/llio.texi b/manual/llio.texi index e55b02d..0dfcdad 100644 --- a/manual/llio.texi +++ b/manual/llio.texi @@ -2569,7 +2569,7 @@ aiocb64}, since the LFS transparently replaces the old interface. @c lll_lock (pd->lock) @asulock @aculock @c atomic_increment ok @c clone ok -@c atomic_decrement ok +@c atomic_fetch_add_relaxed ok @c atomic_exchange_acq ok @c lll_futex_wake ok @c deallocate_stack dup diff --git a/nptl/nptl_setxid.c b/nptl/nptl_setxid.c index aa863c7..e709822 100644 --- a/nptl/nptl_setxid.c +++ b/nptl/nptl_setxid.c @@ -88,7 +88,7 @@ __nptl_setxid_sighandler (int sig, siginfo_t *si, void *ctx) self->setxid_futex = 1; futex_wake (&self->setxid_futex, 1, FUTEX_PRIVATE); - if (atomic_decrement_val (&xidcmd->cntr) == 0) + if (atomic_fetch_add_relaxed (&xidcmd->cntr, -1) == 1) futex_wake ((unsigned int *) &xidcmd->cntr, 1, FUTEX_PRIVATE); } libc_hidden_def (__nptl_setxid_sighandler) diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c index 308db65..e7e4ede 100644 --- a/nptl/pthread_create.c +++ b/nptl/pthread_create.c @@ -861,7 +861,7 @@ __pthread_create_2_1 (pthread_t *newthread, const pthread_attr_t *attr, NOTES above). */ /* Oops, we lied for a second. */ - atomic_decrement (&__nptl_nthreads); + atomic_fetch_add_relaxed (&__nptl_nthreads, -1); /* Free the resources. */ __nptl_deallocate_stack (pd); diff --git a/nscd/nscd-client.h b/nscd/nscd-client.h index fee2a15..ca9e6de 100644 --- a/nscd/nscd-client.h +++ b/nscd/nscd-client.h @@ -421,7 +421,7 @@ __nscd_drop_map_ref (struct mapped_database *map, int *gc_cycle) return -1; } - if (atomic_decrement_val (&map->counter) == 0) + if (atomic_fetch_add_relaxed (&map->counter, -1) == 1) __nscd_unmap (map); } diff --git a/nscd/nscd_getai.c b/nscd/nscd_getai.c index a99a4d8..8e4650e 100644 --- a/nscd/nscd_getai.c +++ b/nscd/nscd_getai.c @@ -198,7 +198,7 @@ __nscd_getai (const char *key, struct nscd_ai_result **result, int *h_errnop) if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) { /* nscd is just running gc now. Disable using the mapping. */ - if (atomic_decrement_val (&mapped->counter) == 0) + if (atomic_fetch_add_relaxed (&mapped->counter, -1) == 1) __nscd_unmap (mapped); mapped = NO_MAPPING; } diff --git a/nscd/nscd_getgr_r.c b/nscd/nscd_getgr_r.c index 3636c03..bde3b58 100644 --- a/nscd/nscd_getgr_r.c +++ b/nscd/nscd_getgr_r.c @@ -312,7 +312,7 @@ nscd_getgr_r (const char *key, size_t keylen, request_type type, if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) { /* nscd is just running gc now. Disable using the mapping. */ - if (atomic_decrement_val (&mapped->counter) == 0) + if (atomic_fetch_add_relaxed (&mapped->counter, -1) == 1) __nscd_unmap (mapped); mapped = NO_MAPPING; } diff --git a/nscd/nscd_gethst_r.c b/nscd/nscd_gethst_r.c index 9becb62..31d1358 100644 --- a/nscd/nscd_gethst_r.c +++ b/nscd/nscd_gethst_r.c @@ -440,7 +440,7 @@ nscd_gethst_r (const char *key, size_t keylen, request_type type, if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) { /* nscd is just running gc now. Disable using the mapping. */ - if (atomic_decrement_val (&mapped->counter) == 0) + if (atomic_fetch_add_relaxed (&mapped->counter, -1) == 1) __nscd_unmap (mapped); mapped = NO_MAPPING; } diff --git a/nscd/nscd_getpw_r.c b/nscd/nscd_getpw_r.c index 20986f4..82fdd17 100644 --- a/nscd/nscd_getpw_r.c +++ b/nscd/nscd_getpw_r.c @@ -225,7 +225,7 @@ nscd_getpw_r (const char *key, size_t keylen, request_type type, if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) { /* nscd is just running gc now. Disable using the mapping. */ - if (atomic_decrement_val (&mapped->counter) == 0) + if (atomic_fetch_add_relaxed (&mapped->counter, -1) == 1) __nscd_unmap (mapped); mapped = NO_MAPPING; } diff --git a/nscd/nscd_getserv_r.c b/nscd/nscd_getserv_r.c index 42b875d..de843b3 100644 --- a/nscd/nscd_getserv_r.c +++ b/nscd/nscd_getserv_r.c @@ -365,7 +365,7 @@ nscd_getserv_r (const char *crit, size_t critlen, const char *proto, if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) { /* nscd is just running gc now. Disable using the mapping. */ - if (atomic_decrement_val (&mapped->counter) == 0) + if (atomic_fetch_add_relaxed (&mapped->counter, -1) == 1) __nscd_unmap (mapped); mapped = NO_MAPPING; } diff --git a/nscd/nscd_helper.c b/nscd/nscd_helper.c index 8e66fa2..0651817 100644 --- a/nscd/nscd_helper.c +++ b/nscd/nscd_helper.c @@ -390,7 +390,7 @@ __nscd_get_mapping (request_type type, const char *key, struct mapped_database *oldval = *mappedp; *mappedp = result; - if (oldval != NULL && atomic_decrement_val (&oldval->counter) == 0) + if (oldval != NULL && atomic_fetch_add_relaxed (&oldval->counter, -1) == 1) __nscd_unmap (oldval); return result; diff --git a/nscd/nscd_initgroups.c b/nscd/nscd_initgroups.c index dfce76a..47b6deb 100644 --- a/nscd/nscd_initgroups.c +++ b/nscd/nscd_initgroups.c @@ -166,7 +166,7 @@ __nscd_getgrouplist (const char *user, gid_t group, long int *size, if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) { /* nscd is just running gc now. Disable using the mapping. */ - if (atomic_decrement_val (&mapped->counter) == 0) + if (atomic_fetch_add_relaxed (&mapped->counter, -1) == 1) __nscd_unmap (mapped); mapped = NO_MAPPING; } diff --git a/nscd/nscd_netgroup.c b/nscd/nscd_netgroup.c index 7e51dd3..11b7f32 100644 --- a/nscd/nscd_netgroup.c +++ b/nscd/nscd_netgroup.c @@ -148,7 +148,7 @@ __nscd_setnetgrent (const char *group, struct __netgrent *datap) if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) { /* nscd is just running gc now. Disable using the mapping. */ - if (atomic_decrement_val (&mapped->counter) == 0) + if (atomic_fetch_add_relaxed (&mapped->counter, -1) == 1) __nscd_unmap (mapped); mapped = NO_MAPPING; } @@ -272,7 +272,7 @@ __nscd_innetgr (const char *netgroup, const char *host, const char *user, if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) { /* nscd is just running gc now. Disable using the mapping. */ - if (atomic_decrement_val (&mapped->counter) == 0) + if (atomic_fetch_add_relaxed (&mapped->counter, -1) == 1) __nscd_unmap (mapped); mapped = NO_MAPPING; } -- 2.7.4