scftorture: Add smp_call_function_single() memory-ordering checks (b93e21a5) · Commits · 戴 / test

kernel/scftorture.c

+48 −8

Original line number	Diff line number	Diff line
		@@ -117,9 +117,20 @@ static struct scf_selector scf_sel_array[SCF_NPRIMS];
		static int scf_sel_array_len;
		static unsigned long scf_sel_totweight;

		// Communicate between caller and handler.
		struct scf_check {
		bool scfc_in;
		bool scfc_out;
		int scfc_cpu; // -1 for not _single().
		bool scfc_wait;
		};

		// Use to wait for all threads to start.
		static atomic_t n_started;
		static atomic_t n_errs;
		static atomic_t n_mb_in_errs;
		static atomic_t n_mb_out_errs;
		static atomic_t n_alloc_errs;
		static bool scfdone;

		DEFINE_TORTURE_RANDOM_PERCPU(scf_torture_rand);
		@@ -222,24 +233,27 @@ static struct scf_selector scf_sel_rand(struct torture_random_state trsp)
		// Update statistics and occasionally burn up mass quantities of CPU time,
		// if told to do so via scftorture.longwait. Otherwise, occasionally burn
		// a little bit.
		static void scf_handler(void *unused)
		static void scf_handler(void *scfc_in)
		{
		int i;
		int j;
		unsigned long r = torture_random(this_cpu_ptr(&scf_torture_rand));
		struct scf_check *scfcp = scfc_in;

		if (likely(scfcp) && WARN_ON_ONCE(unlikely(!READ_ONCE(scfcp->scfc_in))))
		atomic_inc(&n_mb_in_errs);
		this_cpu_inc(scf_invoked_count);
		if (longwait <= 0) {
		if (!(r & 0xffc0))
		udelay(r & 0x3f);
		return;
		goto out;
		}
		if (r & 0xfff)
		return;
		goto out;
		r = (r >> 12);
		if (longwait <= 0) {
		udelay((r & 0xff) + 1);
		return;
		goto out;
		}
		r = r % longwait + 1;
		for (i = 0; i < r; i++) {
		@@ -248,14 +262,24 @@ static void scf_handler(void *unused)
		cpu_relax();
		}
		}
		out:
		if (unlikely(!scfcp))
		return;
		if (scfcp->scfc_wait)
		WRITE_ONCE(scfcp->scfc_out, true);
		else
		kfree(scfcp);
		}

		// As above, but check for correct CPU.
		static void scf_handler_1(void *me)
		static void scf_handler_1(void *scfc_in)
		{
		if (WARN_ON_ONCE(smp_processor_id() != (uintptr_t)me))
		struct scf_check *scfcp = scfc_in;

		if (likely(scfcp) && WARN_ONCE(smp_processor_id() != scfcp->scfc_cpu, "%s: Wanted CPU %d got CPU %d\n", __func__, scfcp->scfc_cpu, smp_processor_id())) {
		atomic_inc(&n_errs);
		scf_handler(NULL);
		}
		scf_handler(scfcp);
		}

		// Randomly do an smp_call_function*() invocation.
		@@ -263,6 +287,7 @@ static void scftorture_invoke_one(struct scf_statistics *scfp, struct torture_ra
		{
		uintptr_t cpu;
		int ret;
		struct scf_check *scfcp = NULL;
		struct scf_selector *scfsp = scf_sel_rand(trsp);

		if (use_cpus_read_lock)
		@@ -271,17 +296,32 @@ static void scftorture_invoke_one(struct scf_statistics *scfp, struct torture_ra
		preempt_disable();
		switch (scfsp->scfs_prim) {
		case SCF_PRIM_SINGLE:
		scfcp = kmalloc(sizeof(*scfcp), GFP_ATOMIC);
		if (WARN_ON_ONCE(!scfcp))
		atomic_inc(&n_alloc_errs);
		cpu = torture_random(trsp) % nr_cpu_ids;
		if (scfsp->scfs_wait)
		scfp->n_single_wait++;
		else
		scfp->n_single++;
		ret = smp_call_function_single(cpu, scf_handler_1, (void *)cpu, scfsp->scfs_wait);
		if (scfcp) {
		scfcp->scfc_cpu = cpu;
		scfcp->scfc_wait = scfsp->scfs_wait;
		scfcp->scfc_out = false;
		scfcp->scfc_in = true;
		}
		ret = smp_call_function_single(cpu, scf_handler_1, (void *)scfcp, scfsp->scfs_wait);
		if (ret) {
		if (scfsp->scfs_wait)
		scfp->n_single_wait_ofl++;
		else
		scfp->n_single_ofl++;
		kfree(scfcp);
		} else if (scfcp && scfsp->scfs_wait) {
		if (WARN_ON_ONCE(!scfcp->scfc_out))
		atomic_inc(&n_mb_out_errs); // Leak rather than trash!
		else
		kfree(scfcp);
		}
		break;
		case SCF_PRIM_MANY:

Admin message