From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- tools/lib/api/fd/Build | 1 + tools/lib/api/fd/array.c | 149 +++++++++++++++++++++++++++++++++++++++++++++++ tools/lib/api/fd/array.h | 59 +++++++++++++++++++ 3 files changed, 209 insertions(+) create mode 100644 tools/lib/api/fd/Build create mode 100644 tools/lib/api/fd/array.c create mode 100644 tools/lib/api/fd/array.h (limited to 'tools/lib/api/fd') diff --git a/tools/lib/api/fd/Build b/tools/lib/api/fd/Build new file mode 100644 index 000000000..605d99f6d --- /dev/null +++ b/tools/lib/api/fd/Build @@ -0,0 +1 @@ +libapi-y += array.o diff --git a/tools/lib/api/fd/array.c b/tools/lib/api/fd/array.c new file mode 100644 index 000000000..f0f195207 --- /dev/null +++ b/tools/lib/api/fd/array.c @@ -0,0 +1,149 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2014, Red Hat Inc, Arnaldo Carvalho de Melo + */ +#include "array.h" +#include +#include +#include +#include +#include +#include + +void fdarray__init(struct fdarray *fda, int nr_autogrow) +{ + fda->entries = NULL; + fda->priv = NULL; + fda->nr = fda->nr_alloc = 0; + fda->nr_autogrow = nr_autogrow; +} + +int fdarray__grow(struct fdarray *fda, int nr) +{ + struct priv *priv; + int nr_alloc = fda->nr_alloc + nr; + size_t psize = sizeof(fda->priv[0]) * nr_alloc; + size_t size = sizeof(struct pollfd) * nr_alloc; + struct pollfd *entries = realloc(fda->entries, size); + + if (entries == NULL) + return -ENOMEM; + + priv = realloc(fda->priv, psize); + if (priv == NULL) { + free(entries); + return -ENOMEM; + } + + memset(&entries[fda->nr_alloc], 0, sizeof(struct pollfd) * nr); + memset(&priv[fda->nr_alloc], 0, sizeof(fda->priv[0]) * nr); + + fda->nr_alloc = nr_alloc; + fda->entries = entries; + fda->priv = priv; + return 0; +} + +struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow) +{ + struct fdarray *fda = calloc(1, sizeof(*fda)); + + if (fda != NULL) { + if (fdarray__grow(fda, nr_alloc)) { + free(fda); + fda = NULL; + } else { + fda->nr_autogrow = nr_autogrow; + } + } + + return fda; +} + +void fdarray__exit(struct fdarray *fda) +{ + free(fda->entries); + free(fda->priv); + fdarray__init(fda, 0); +} + +void fdarray__delete(struct fdarray *fda) +{ + fdarray__exit(fda); + free(fda); +} + +int fdarray__add(struct fdarray *fda, int fd, short revents, enum fdarray_flags flags) +{ + int pos = fda->nr; + + if (fda->nr == fda->nr_alloc && + fdarray__grow(fda, fda->nr_autogrow) < 0) + return -ENOMEM; + + fda->entries[fda->nr].fd = fd; + fda->entries[fda->nr].events = revents; + fda->priv[fda->nr].flags = flags; + fda->nr++; + return pos; +} + +int fdarray__dup_entry_from(struct fdarray *fda, int pos, struct fdarray *from) +{ + struct pollfd *entry; + int npos; + + if (pos >= from->nr) + return -EINVAL; + + entry = &from->entries[pos]; + + npos = fdarray__add(fda, entry->fd, entry->events, from->priv[pos].flags); + if (npos >= 0) + fda->priv[npos] = from->priv[pos]; + + return npos; +} + +int fdarray__filter(struct fdarray *fda, short revents, + void (*entry_destructor)(struct fdarray *fda, int fd, void *arg), + void *arg) +{ + int fd, nr = 0; + + if (fda->nr == 0) + return 0; + + for (fd = 0; fd < fda->nr; ++fd) { + if (!fda->entries[fd].events) + continue; + + if (fda->entries[fd].revents & revents) { + if (entry_destructor) + entry_destructor(fda, fd, arg); + + fda->entries[fd].revents = fda->entries[fd].events = 0; + continue; + } + + if (!(fda->priv[fd].flags & fdarray_flag__nonfilterable)) + ++nr; + } + + return nr; +} + +int fdarray__poll(struct fdarray *fda, int timeout) +{ + return poll(fda->entries, fda->nr, timeout); +} + +int fdarray__fprintf(struct fdarray *fda, FILE *fp) +{ + int fd, printed = fprintf(fp, "%d [ ", fda->nr); + + for (fd = 0; fd < fda->nr; ++fd) + printed += fprintf(fp, "%s%d", fd ? ", " : "", fda->entries[fd].fd); + + return printed + fprintf(fp, " ]"); +} diff --git a/tools/lib/api/fd/array.h b/tools/lib/api/fd/array.h new file mode 100644 index 000000000..5c01f7b05 --- /dev/null +++ b/tools/lib/api/fd/array.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __API_FD_ARRAY__ +#define __API_FD_ARRAY__ + +#include + +struct pollfd; + +/** + * struct fdarray: Array of file descriptors + * + * @priv: Per array entry priv area, users should access just its contents, + * not set it to anything, as it is kept in synch with @entries, being + * realloc'ed, * for instance, in fdarray__{grow,filter}. + * + * I.e. using 'fda->priv[N].idx = * value' where N < fda->nr is ok, + * but doing 'fda->priv = malloc(M)' is not allowed. + */ +struct fdarray { + int nr; + int nr_alloc; + int nr_autogrow; + struct pollfd *entries; + struct priv { + union { + int idx; + void *ptr; + }; + unsigned int flags; + } *priv; +}; + +enum fdarray_flags { + fdarray_flag__default = 0x00000000, + fdarray_flag__nonfilterable = 0x00000001, + fdarray_flag__non_perf_event = 0x00000002, +}; + +void fdarray__init(struct fdarray *fda, int nr_autogrow); +void fdarray__exit(struct fdarray *fda); + +struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow); +void fdarray__delete(struct fdarray *fda); + +int fdarray__add(struct fdarray *fda, int fd, short revents, enum fdarray_flags flags); +int fdarray__dup_entry_from(struct fdarray *fda, int pos, struct fdarray *from); +int fdarray__poll(struct fdarray *fda, int timeout); +int fdarray__filter(struct fdarray *fda, short revents, + void (*entry_destructor)(struct fdarray *fda, int fd, void *arg), + void *arg); +int fdarray__grow(struct fdarray *fda, int extra); +int fdarray__fprintf(struct fdarray *fda, FILE *fp); + +static inline int fdarray__available_entries(struct fdarray *fda) +{ + return fda->nr_alloc - fda->nr; +} + +#endif /* __API_FD_ARRAY__ */ -- cgit v1.3.1