tools lib api: Adopt fdarray class from perf's evlist

The extensible file description array that grew in the perf_evlist class
can be useful for other tools, as it is not something that only evlists
need, so move it to tools/lib/api/fd to ease sharing it.

v2: Don't use {} like in:

 libapi_dirs:
	$(QUIET_MKDIR)mkdir -p $(OUTPUT){fs,fd}/

in Makefiles, as it will not work in some systems, as in ubuntu13.10.

v3: Add fd/*.[ch] to LIBAPIKFS_SOURCES (Fix from Jiri Olsa)

v4: Leave the fcntl(fd, O_NONBLOCK) in the evlist layer, remains to
    be checked if it is really needed there, but has no place in the
    fdarray class (Fix from Jiri Olsa)

v5: Remove evlist details from fdarray grow/filter tests. Improve it a
    bit doing more tests about expected internal state.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-kleuni3hckbc3s0lu6yb9x40@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 9 insertions, 48 deletions

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 5ff3c667542f..398dab1a08cc 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -37,6 +37,7 @@ void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
                 INIT_HLIST_HEAD(&evlist->heads[i]);
         INIT_LIST_HEAD(&evlist->entries);
         perf_evlist__set_maps(evlist, cpus, threads);
+        fdarray__init(&evlist->pollfd, 64);
         evlist->workload.pid = -1;
 }
 
@@ -102,7 +103,7 @@ static void perf_evlist__purge(struct perf_evlist *evlist)
 void perf_evlist__exit(struct perf_evlist *evlist)
 {
         zfree(&evlist->mmap);
-        zfree(&evlist->pollfd);
+        fdarray__exit(&evlist->pollfd);
 }
 
 void perf_evlist__delete(struct perf_evlist *evlist)
@@ -402,20 +403,6 @@ int perf_evlist__enable_event_idx(struct perf_evlist *evlist,
                 return perf_evlist__enable_event_thread(evlist, evsel, idx);
 }
 
-static int perf_evlist__grow_pollfd(struct perf_evlist *evlist, int hint)
-{
-        int nr_fds_alloc = evlist->nr_fds_alloc + hint;
-        size_t size = sizeof(struct pollfd) * nr_fds_alloc;
-        struct pollfd *pollfd = realloc(evlist->pollfd, size);
-
-        if (pollfd == NULL)
-                return -ENOMEM;
-
-        evlist->nr_fds_alloc = nr_fds_alloc;
-        evlist->pollfd       = pollfd;
-        return 0;
-}
-
 int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
 {
         int nr_cpus = cpu_map__nr(evlist->cpus);
@@ -430,8 +417,8 @@ int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
                         nfds += nr_cpus * nr_threads;
         }
 
-        if (evlist->nr_fds_alloc - evlist->nr_fds < nfds &&
-            perf_evlist__grow_pollfd(evlist, nfds) < 0)
+        if (fdarray__available_entries(&evlist->pollfd) < nfds &&
+            fdarray__grow(&evlist->pollfd, nfds) < 0)
                 return -ENOMEM;
 
         return 0;
@@ -439,45 +426,19 @@ int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
 
 int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd)
 {
-        /*
-         * XXX: 64 is arbitrary, just not to call realloc at each fd.
-         *      Find a better autogrowing heuristic
-         */
-        if (evlist->nr_fds == evlist->nr_fds_alloc &&
-            perf_evlist__grow_pollfd(evlist, 64) < 0)
-                return -ENOMEM;
-
         fcntl(fd, F_SETFL, O_NONBLOCK);
-        evlist->pollfd[evlist->nr_fds].fd = fd;
-        evlist->pollfd[evlist->nr_fds].events = POLLIN | POLLERR | POLLHUP;
-        evlist->nr_fds++;
-        return 0;
+
+        return fdarray__add(&evlist->pollfd, fd, POLLIN | POLLERR | POLLHUP);
 }
 
 int perf_evlist__filter_pollfd(struct perf_evlist *evlist, short revents_and_mask)
 {
-        int fd, nr_fds = 0;
-
-        if (evlist->nr_fds == 0)
-                return 0;
-
-        for (fd = 0; fd < evlist->nr_fds; ++fd) {
-                if (evlist->pollfd[fd].revents & revents_and_mask)
-                        continue;
-
-                if (fd != nr_fds)
-                        evlist->pollfd[nr_fds] = evlist->pollfd[fd];
-
-                ++nr_fds;
-        }
-
-        evlist->nr_fds = nr_fds;
-        return nr_fds;
+        return fdarray__filter(&evlist->pollfd, revents_and_mask);
 }
 
 int perf_evlist__poll(struct perf_evlist *evlist, int timeout)
 {
-        return poll(evlist->pollfd, evlist->nr_fds, timeout);
+        return fdarray__poll(&evlist->pollfd, timeout);
 }
 
 static void perf_evlist__id_hash(struct perf_evlist *evlist,
@@ -935,7 +896,7 @@ int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
         if (evlist->mmap == NULL && perf_evlist__alloc_mmap(evlist) < 0)
                 return -ENOMEM;
 
-        if (evlist->pollfd == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
+        if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
                 return -ENOMEM;
 
         evlist->overwrite = overwrite;