Since I butchered this I figured better to make sure we have testcases for this now. Since we only have a locking context for __GFP_FS that's the only thing we're testing right now.
Acked-by: Peter Zijlstra (Intel) peterz@infradead.org Cc: linux-fsdevel@vger.kernel.org Cc: Dave Chinner david@fromorbit.com Cc: Qian Cai cai@lca.pw Cc: linux-xfs@vger.kernel.org Cc: Thomas Hellström (Intel) thomas_os@shipmail.org Cc: Andrew Morton akpm@linux-foundation.org Cc: Jason Gunthorpe jgg@mellanox.com Cc: linux-mm@kvack.org Cc: linux-rdma@vger.kernel.org Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Christian König christian.koenig@amd.com Cc: "Matthew Wilcox (Oracle)" willy@infradead.org Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Peter Zijlstra peterz@infradead.org Cc: Ingo Molnar mingo@redhat.com Cc: Will Deacon will@kernel.org Cc: linux-kernel@vger.kernel.org --- lib/locking-selftest.c | 47 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+)
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c index a899b3f0e2e5..ad47c3358e30 100644 --- a/lib/locking-selftest.c +++ b/lib/locking-selftest.c @@ -15,6 +15,7 @@ #include <linux/mutex.h> #include <linux/ww_mutex.h> #include <linux/sched.h> +#include <linux/sched/mm.h> #include <linux/delay.h> #include <linux/lockdep.h> #include <linux/spinlock.h> @@ -2357,6 +2358,50 @@ static void queued_read_lock_tests(void) pr_cont("\n"); }
+static void fs_reclaim_correct_nesting(void) +{ + fs_reclaim_acquire(GFP_KERNEL); + might_alloc(GFP_NOFS); + fs_reclaim_release(GFP_KERNEL); +} + +static void fs_reclaim_wrong_nesting(void) +{ + fs_reclaim_acquire(GFP_KERNEL); + might_alloc(GFP_KERNEL); + fs_reclaim_release(GFP_KERNEL); +} + +static void fs_reclaim_protected_nesting(void) +{ + unsigned int flags; + + fs_reclaim_acquire(GFP_KERNEL); + flags = memalloc_nofs_save(); + might_alloc(GFP_KERNEL); + memalloc_nofs_restore(flags); + fs_reclaim_release(GFP_KERNEL); +} + +static void fs_reclaim_tests(void) +{ + printk(" --------------------\n"); + printk(" | fs_reclaim tests |\n"); + printk(" --------------------\n"); + + print_testname("correct nesting"); + dotest(fs_reclaim_correct_nesting, SUCCESS, 0); + pr_cont("\n"); + + print_testname("wrong nesting"); + dotest(fs_reclaim_wrong_nesting, FAILURE, 0); + pr_cont("\n"); + + print_testname("protected nesting"); + dotest(fs_reclaim_protected_nesting, SUCCESS, 0); + pr_cont("\n"); +} + void locking_selftest(void) { /* @@ -2478,6 +2523,8 @@ void locking_selftest(void) if (IS_ENABLED(CONFIG_QUEUED_RWLOCKS)) queued_read_lock_tests();
+ fs_reclaim_tests(); + if (unexpected_testcase_failures) { printk("-----------------------------------------------------------------\n"); debug_locks = 0;