Re: [PATCH 3/5] selftests/liveupdate: Test session and file limit removal

[Pasha Tatashin <pasha.tatashin@soleen.com>]

On 05-12 16:04, Pratyush Yadav wrote:
> On Tue, Apr 14 2026, Pasha Tatashin wrote:
> 
> > With the removal of static limits on the number of sessions and files per
> > session, the orchestrator now uses dynamic allocation.
> >
> > Add new test cases to verify that the system can handle a large number of
> > sessions and files. These tests ensure that the dynamic block allocation
> > and reuse logic for session metadata and outgoing files work correctly
> > beyond the previous static limits.
> >
> > Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
> > ---
> >  .../testing/selftests/liveupdate/liveupdate.c | 99 +++++++++++++++++++
> >  1 file changed, 99 insertions(+)
> >
> > diff --git a/tools/testing/selftests/liveupdate/liveupdate.c b/tools/testing/selftests/liveupdate/liveupdate.c
> > index 37c808fbe1e9..0eaf97b19267 100644
> > --- a/tools/testing/selftests/liveupdate/liveupdate.c
> > +++ b/tools/testing/selftests/liveupdate/liveupdate.c
> > @@ -22,6 +22,7 @@
> >  #include <fcntl.h>
> >  #include <string.h>
> >  #include <sys/ioctl.h>
> > +#include <sys/resource.h>
> >  #include <unistd.h>
> >  
> >  #include <linux/liveupdate.h>
> > @@ -386,4 +387,102 @@ TEST_F(liveupdate_device, prevent_double_preservation)
> >  	ASSERT_EQ(close(session_fd2), 0);
> >  }
> >  
> > +static void ensure_nofile_limit(struct __test_metadata *_metadata,
> > +				long min_limit)
> > +{
> > +	struct rlimit hl;
> > +
> > +	if (getrlimit(RLIMIT_NOFILE, &hl) < 0)
> > +		ksft_exit_fail_msg("getrlimit failed: %s\n", strerror(errno));
> > +
> > +	if (hl.rlim_cur >= min_limit)
> > +		return;
> > +
> > +	hl.rlim_cur = min_limit;
> > +	if (hl.rlim_cur > hl.rlim_max)
> > +		hl.rlim_max = hl.rlim_cur;
> > +
> > +	if (setrlimit(RLIMIT_NOFILE, &hl) < 0) {
> > +		if (errno == EPERM) {
> > +			SKIP(return, "Insufficient privileges to set RLIMIT_NOFILE to %ld",
> > +			     hl.rlim_cur);
> > +		}
> > +		ksft_exit_fail_msg("setrlimit to %ld failed: %s\n",
> > +				   hl.rlim_cur, strerror(errno));
> > +	}
> > +}
> > +
> > +/*
> > + * Test Case: Manage Many Sessions
> > + *
> > + * Verifies that a large number of sessions can be created and then
> > + * destroyed during normal system operation. This specifically tests the
> > + * dynamic block allocation and reuse logic for session metadata management
> > + * without preserving any files.
> > + */
> > +TEST_F(liveupdate_device, preserve_many_sessions)
> > +{
> > +#define MANY_SESSIONS 2000
> > +	int session_fds[MANY_SESSIONS];
> > +	int i;
> > +
> > +	self->fd1 = open(LIVEUPDATE_DEV, O_RDWR);
> > +	if (self->fd1 < 0 && errno == ENOENT)
> > +		SKIP(return, "%s does not exist", LIVEUPDATE_DEV);
> > +	ASSERT_GE(self->fd1, 0);
> > +
> > +	ensure_nofile_limit(_metadata, MANY_SESSIONS + 10);
> > +	if (_metadata->exit_code == KSFT_SKIP)
> > +		return;
> 
> Nit: This is strange. Why not just return errno in ensure_nofile_limit()
> and handle the skipping here? Same below.
> 
> LGTM otherwise.

Good suggestion. Done.