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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /tools/perf/util/comm.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/perf/util/comm.c')
-rw-r--r-- | tools/perf/util/comm.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c new file mode 100644 index 000000000..afb8d4fd2 --- /dev/null +++ b/tools/perf/util/comm.c @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "comm.h" +#include <errno.h> +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <linux/refcount.h> +#include <linux/rbtree.h> +#include <linux/zalloc.h> +#include "rwsem.h" + +struct comm_str { + char *str; + struct rb_node rb_node; + refcount_t refcnt; +}; + +/* Should perhaps be moved to struct machine */ +static struct rb_root comm_str_root; +static struct rw_semaphore comm_str_lock = {.lock = PTHREAD_RWLOCK_INITIALIZER,}; + +static struct comm_str *comm_str__get(struct comm_str *cs) +{ + if (cs && refcount_inc_not_zero(&cs->refcnt)) + return cs; + + return NULL; +} + +static void comm_str__put(struct comm_str *cs) +{ + if (cs && refcount_dec_and_test(&cs->refcnt)) { + down_write(&comm_str_lock); + rb_erase(&cs->rb_node, &comm_str_root); + up_write(&comm_str_lock); + zfree(&cs->str); + free(cs); + } +} + +static struct comm_str *comm_str__alloc(const char *str) +{ + struct comm_str *cs; + + cs = zalloc(sizeof(*cs)); + if (!cs) + return NULL; + + cs->str = strdup(str); + if (!cs->str) { + free(cs); + return NULL; + } + + refcount_set(&cs->refcnt, 1); + + return cs; +} + +static +struct comm_str *__comm_str__findnew(const char *str, struct rb_root *root) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *parent = NULL; + struct comm_str *iter, *new; + int cmp; + + while (*p != NULL) { + parent = *p; + iter = rb_entry(parent, struct comm_str, rb_node); + + /* + * If we race with comm_str__put, iter->refcnt is 0 + * and it will be removed within comm_str__put call + * shortly, ignore it in this search. + */ + cmp = strcmp(str, iter->str); + if (!cmp && comm_str__get(iter)) + return iter; + + if (cmp < 0) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + + new = comm_str__alloc(str); + if (!new) + return NULL; + + rb_link_node(&new->rb_node, parent, p); + rb_insert_color(&new->rb_node, root); + + return new; +} + +static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root) +{ + struct comm_str *cs; + + down_write(&comm_str_lock); + cs = __comm_str__findnew(str, root); + up_write(&comm_str_lock); + + return cs; +} + +struct comm *comm__new(const char *str, u64 timestamp, bool exec) +{ + struct comm *comm = zalloc(sizeof(*comm)); + + if (!comm) + return NULL; + + comm->start = timestamp; + comm->exec = exec; + + comm->comm_str = comm_str__findnew(str, &comm_str_root); + if (!comm->comm_str) { + free(comm); + return NULL; + } + + return comm; +} + +int comm__override(struct comm *comm, const char *str, u64 timestamp, bool exec) +{ + struct comm_str *new, *old = comm->comm_str; + + new = comm_str__findnew(str, &comm_str_root); + if (!new) + return -ENOMEM; + + comm_str__put(old); + comm->comm_str = new; + comm->start = timestamp; + if (exec) + comm->exec = true; + + return 0; +} + +void comm__free(struct comm *comm) +{ + comm_str__put(comm->comm_str); + free(comm); +} + +const char *comm__str(const struct comm *comm) +{ + return comm->comm_str->str; +} |