From 34ff636f322c6d5e4f0a52338fa63a7dff09a495 Mon Sep 17 00:00:00 2001 From: Joel Fernandes Date: Sat, 18 Jul 2026 13:15:36 -0400 Subject: scftorture: Count single_rpc offline failures in statistics output scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes Signed-off-by: Paul E. McKenney --- fs/fs_struct.c | 155 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 fs/fs_struct.c (limited to 'fs/fs_struct.c') diff --git a/fs/fs_struct.c b/fs/fs_struct.c new file mode 100644 index 000000000..394875d06 --- /dev/null +++ b/fs/fs_struct.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +/* + * Replace the fs->{rootmnt,root} with {mnt,dentry}. Put the old values. + * It can block. + */ +void set_fs_root(struct fs_struct *fs, const struct path *path) +{ + struct path old_root; + + path_get(path); + write_seqlock(&fs->seq); + old_root = fs->root; + fs->root = *path; + write_sequnlock(&fs->seq); + if (old_root.dentry) + path_put(&old_root); +} + +/* + * Replace the fs->{pwdmnt,pwd} with {mnt,dentry}. Put the old values. + * It can block. + */ +void set_fs_pwd(struct fs_struct *fs, const struct path *path) +{ + struct path old_pwd; + + path_get(path); + write_seqlock(&fs->seq); + old_pwd = fs->pwd; + fs->pwd = *path; + write_sequnlock(&fs->seq); + + if (old_pwd.dentry) + path_put(&old_pwd); +} + +static inline int replace_path(struct path *p, const struct path *old, const struct path *new) +{ + if (likely(p->dentry != old->dentry || p->mnt != old->mnt)) + return 0; + *p = *new; + return 1; +} + +void chroot_fs_refs(const struct path *old_root, const struct path *new_root) +{ + struct task_struct *g, *p; + struct fs_struct *fs; + int count = 0; + + read_lock(&tasklist_lock); + for_each_process_thread(g, p) { + task_lock(p); + fs = p->fs; + if (fs) { + int hits = 0; + write_seqlock(&fs->seq); + hits += replace_path(&fs->root, old_root, new_root); + hits += replace_path(&fs->pwd, old_root, new_root); + while (hits--) { + count++; + path_get(new_root); + } + write_sequnlock(&fs->seq); + } + task_unlock(p); + } + read_unlock(&tasklist_lock); + while (count--) + path_put(old_root); +} + +void free_fs_struct(struct fs_struct *fs) +{ + path_put(&fs->root); + path_put(&fs->pwd); + kmem_cache_free(fs_cachep, fs); +} + +void exit_fs(struct task_struct *tsk) +{ + struct fs_struct *fs = tsk->fs; + + if (fs) { + int kill; + task_lock(tsk); + read_seqlock_excl(&fs->seq); + tsk->fs = NULL; + kill = !--fs->users; + read_sequnlock_excl(&fs->seq); + task_unlock(tsk); + if (kill) + free_fs_struct(fs); + } +} + +struct fs_struct *copy_fs_struct(struct fs_struct *old) +{ + struct fs_struct *fs = kmem_cache_alloc(fs_cachep, GFP_KERNEL); + /* We don't need to lock fs - think why ;-) */ + if (fs) { + fs->users = 1; + fs->in_exec = 0; + seqlock_init(&fs->seq); + fs->umask = old->umask; + + read_seqlock_excl(&old->seq); + fs->root = old->root; + path_get(&fs->root); + fs->pwd = old->pwd; + path_get(&fs->pwd); + read_sequnlock_excl(&old->seq); + } + return fs; +} + +int unshare_fs_struct(void) +{ + struct fs_struct *fs = current->fs; + struct fs_struct *new_fs = copy_fs_struct(fs); + int kill; + + if (!new_fs) + return -ENOMEM; + + task_lock(current); + read_seqlock_excl(&fs->seq); + kill = !--fs->users; + current->fs = new_fs; + read_sequnlock_excl(&fs->seq); + task_unlock(current); + + if (kill) + free_fs_struct(fs); + + return 0; +} +EXPORT_SYMBOL_GPL(unshare_fs_struct); + +/* to be mentioned only in INIT_TASK */ +struct fs_struct init_fs = { + .users = 1, + .seq = __SEQLOCK_UNLOCKED(init_fs.seq), + .umask = 0022, +}; -- cgit v1.3.1