libperf: Avoid internal moving of fdarray fds

Avoid moving of fds by fdarray__filter() so fds indices returned by
fdarray__add() can be used for access and processing of objects at
struct pollfd *entries.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/676844f8-55d3-c628-23db-aa163a81519e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Alexey Budankov 2020-07-17 09:59:12 +03:00 committed by Arnaldo Carvalho de Melo
parent 070b3b5ad7
commit 59b4412f27
2 changed files with 7 additions and 24 deletions

View File

@ -93,22 +93,21 @@ int fdarray__filter(struct fdarray *fda, short revents,
return 0; return 0;
for (fd = 0; fd < fda->nr; ++fd) { for (fd = 0; fd < fda->nr; ++fd) {
if (!fda->entries[fd].events)
continue;
if (fda->entries[fd].revents & revents) { if (fda->entries[fd].revents & revents) {
if (entry_destructor) if (entry_destructor)
entry_destructor(fda, fd, arg); entry_destructor(fda, fd, arg);
fda->entries[fd].revents = fda->entries[fd].events = 0;
continue; continue;
} }
if (fd != nr) {
fda->entries[nr] = fda->entries[fd];
fda->priv[nr] = fda->priv[fd];
}
++nr; ++nr;
} }
return fda->nr = nr; return nr;
} }
int fdarray__poll(struct fdarray *fda, int timeout) int fdarray__poll(struct fdarray *fda, int timeout)

View File

@ -12,6 +12,7 @@ static void fdarray__init_revents(struct fdarray *fda, short revents)
for (fd = 0; fd < fda->nr; ++fd) { for (fd = 0; fd < fda->nr; ++fd) {
fda->entries[fd].fd = fda->nr - fd; fda->entries[fd].fd = fda->nr - fd;
fda->entries[fd].events = revents;
fda->entries[fd].revents = revents; fda->entries[fd].revents = revents;
} }
} }
@ -29,7 +30,7 @@ static int fdarray__fprintf_prefix(struct fdarray *fda, const char *prefix, FILE
int test__fdarray__filter(struct test *test __maybe_unused, int subtest __maybe_unused) int test__fdarray__filter(struct test *test __maybe_unused, int subtest __maybe_unused)
{ {
int nr_fds, expected_fd[2], fd, err = TEST_FAIL; int nr_fds, err = TEST_FAIL;
struct fdarray *fda = fdarray__new(5, 5); struct fdarray *fda = fdarray__new(5, 5);
if (fda == NULL) { if (fda == NULL) {
@ -55,7 +56,6 @@ int test__fdarray__filter(struct test *test __maybe_unused, int subtest __maybe_
fdarray__init_revents(fda, POLLHUP); fdarray__init_revents(fda, POLLHUP);
fda->entries[2].revents = POLLIN; fda->entries[2].revents = POLLIN;
expected_fd[0] = fda->entries[2].fd;
pr_debug("\nfiltering all but fda->entries[2]:"); pr_debug("\nfiltering all but fda->entries[2]:");
fdarray__fprintf_prefix(fda, "before", stderr); fdarray__fprintf_prefix(fda, "before", stderr);
@ -66,17 +66,9 @@ int test__fdarray__filter(struct test *test __maybe_unused, int subtest __maybe_
goto out_delete; goto out_delete;
} }
if (fda->entries[0].fd != expected_fd[0]) {
pr_debug("\nfda->entries[0].fd=%d != %d\n",
fda->entries[0].fd, expected_fd[0]);
goto out_delete;
}
fdarray__init_revents(fda, POLLHUP); fdarray__init_revents(fda, POLLHUP);
fda->entries[0].revents = POLLIN; fda->entries[0].revents = POLLIN;
expected_fd[0] = fda->entries[0].fd;
fda->entries[3].revents = POLLIN; fda->entries[3].revents = POLLIN;
expected_fd[1] = fda->entries[3].fd;
pr_debug("\nfiltering all but (fda->entries[0], fda->entries[3]):"); pr_debug("\nfiltering all but (fda->entries[0], fda->entries[3]):");
fdarray__fprintf_prefix(fda, "before", stderr); fdarray__fprintf_prefix(fda, "before", stderr);
@ -88,14 +80,6 @@ int test__fdarray__filter(struct test *test __maybe_unused, int subtest __maybe_
goto out_delete; goto out_delete;
} }
for (fd = 0; fd < 2; ++fd) {
if (fda->entries[fd].fd != expected_fd[fd]) {
pr_debug("\nfda->entries[%d].fd=%d != %d\n", fd,
fda->entries[fd].fd, expected_fd[fd]);
goto out_delete;
}
}
pr_debug("\n"); pr_debug("\n");
err = 0; err = 0;