Re: [PATCH v3 11/18] perf dso: Update use of pthread mutex

From: Ian Rogers
Date: Fri Aug 26 2022 - 12:05:33 EST


On Fri, Aug 26, 2022 at 3:37 AM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>
> On 24/08/22 18:38, Ian Rogers wrote:
> > Switch to the use of mutex wrappers that provide better error checking.
> >
> > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> > ---
> > tools/perf/util/dso.c | 12 ++++++------
>
> Some not done yet
>
> $ grep -i pthread_mut tools/perf/util/dso.c
> static pthread_mutex_t dso__data_open_lock = PTHREAD_MUTEX_INITIALIZER;
> pthread_mutex_lock(&dso__data_open_lock);
> pthread_mutex_unlock(&dso__data_open_lock);
> if (pthread_mutex_lock(&dso__data_open_lock) < 0)
> pthread_mutex_unlock(&dso__data_open_lock);
> pthread_mutex_unlock(&dso__data_open_lock);
> pthread_mutex_lock(&dso__data_open_lock);
> pthread_mutex_unlock(&dso__data_open_lock);
> pthread_mutex_lock(&dso__data_open_lock);
> pthread_mutex_unlock(&dso__data_open_lock);

Yes, these are all solely dso__data_open_lock that lacks any clear
init/exit code to place the initialization/destruction hooks onto. I
don't plan to alter these in this patch set.

Thanks,
Ian

>
> > tools/perf/util/dso.h | 4 ++--
> > tools/perf/util/symbol.c | 4 ++--
> > 3 files changed, 10 insertions(+), 10 deletions(-)
> >
> > diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
> > index 5ac13958d1bd..a9789a955403 100644
> > --- a/tools/perf/util/dso.c
> > +++ b/tools/perf/util/dso.c
> > @@ -795,7 +795,7 @@ dso_cache__free(struct dso *dso)
> > struct rb_root *root = &dso->data.cache;
> > struct rb_node *next = rb_first(root);
> >
> > - pthread_mutex_lock(&dso->lock);
> > + mutex_lock(&dso->lock);
> > while (next) {
> > struct dso_cache *cache;
> >
> > @@ -804,7 +804,7 @@ dso_cache__free(struct dso *dso)
> > rb_erase(&cache->rb_node, root);
> > free(cache);
> > }
> > - pthread_mutex_unlock(&dso->lock);
> > + mutex_unlock(&dso->lock);
> > }
> >
> > static struct dso_cache *__dso_cache__find(struct dso *dso, u64 offset)
> > @@ -841,7 +841,7 @@ dso_cache__insert(struct dso *dso, struct dso_cache *new)
> > struct dso_cache *cache;
> > u64 offset = new->offset;
> >
> > - pthread_mutex_lock(&dso->lock);
> > + mutex_lock(&dso->lock);
> > while (*p != NULL) {
> > u64 end;
> >
> > @@ -862,7 +862,7 @@ dso_cache__insert(struct dso *dso, struct dso_cache *new)
> >
> > cache = NULL;
> > out:
> > - pthread_mutex_unlock(&dso->lock);
> > + mutex_unlock(&dso->lock);
> > return cache;
> > }
> >
> > @@ -1297,7 +1297,7 @@ struct dso *dso__new_id(const char *name, struct dso_id *id)
> > dso->root = NULL;
> > INIT_LIST_HEAD(&dso->node);
> > INIT_LIST_HEAD(&dso->data.open_entry);
> > - pthread_mutex_init(&dso->lock, NULL);
> > + mutex_init(&dso->lock);
> > refcount_set(&dso->refcnt, 1);
> > }
> >
> > @@ -1336,7 +1336,7 @@ void dso__delete(struct dso *dso)
> > dso__free_a2l(dso);
> > zfree(&dso->symsrc_filename);
> > nsinfo__zput(dso->nsinfo);
> > - pthread_mutex_destroy(&dso->lock);
> > + mutex_destroy(&dso->lock);
> > free(dso);
> > }
> >
> > diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
> > index 66981c7a9a18..58d94175e714 100644
> > --- a/tools/perf/util/dso.h
> > +++ b/tools/perf/util/dso.h
> > @@ -2,7 +2,6 @@
> > #ifndef __PERF_DSO
> > #define __PERF_DSO
> >
> > -#include <pthread.h>
> > #include <linux/refcount.h>
> > #include <linux/types.h>
> > #include <linux/rbtree.h>
> > @@ -11,6 +10,7 @@
> > #include <stdio.h>
> > #include <linux/bitops.h>
> > #include "build-id.h"
> > +#include "mutex.h"
> >
> > struct machine;
> > struct map;
> > @@ -145,7 +145,7 @@ struct dso_cache {
> > struct auxtrace_cache;
> >
> > struct dso {
> > - pthread_mutex_t lock;
> > + struct mutex lock;
> > struct list_head node;
> > struct rb_node rb_node; /* rbtree node sorted by long name */
> > struct rb_root *root; /* root of rbtree that rb_node is in */
> > diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> > index a4b22caa7c24..656d9b4dd456 100644
> > --- a/tools/perf/util/symbol.c
> > +++ b/tools/perf/util/symbol.c
> > @@ -1800,7 +1800,7 @@ int dso__load(struct dso *dso, struct map *map)
> > }
> >
> > nsinfo__mountns_enter(dso->nsinfo, &nsc);
> > - pthread_mutex_lock(&dso->lock);
> > + mutex_lock(&dso->lock);
> >
> > /* check again under the dso->lock */
> > if (dso__loaded(dso)) {
> > @@ -1964,7 +1964,7 @@ int dso__load(struct dso *dso, struct map *map)
> > ret = 0;
> > out:
> > dso__set_loaded(dso);
> > - pthread_mutex_unlock(&dso->lock);
> > + mutex_unlock(&dso->lock);
> > nsinfo__mountns_exit(&nsc);
> >
> > return ret;
>