/* * Cache operations for Coda. * For Linux 2.1: (C) 1997 Carnegie Mellon University * For Linux 2.3: (C) 2000 Carnegie Mellon University * * Carnegie Mellon encourages users of this code to contribute improvements * to the Coda project http://www.coda.cs.cmu.edu/ . */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "coda_linux.h" #include "coda_cache.h" static atomic_t permission_epoch = ATOMIC_INIT(0); /* replace or extend an acl cache hit */ void coda_cache_enter(struct inode *inode, int mask) { struct coda_inode_info *cii = ITOC(inode); spin_lock(&cii->c_lock); cii->c_cached_epoch = atomic_read(&permission_epoch); if (!uid_eq(cii->c_uid, current_fsuid())) { cii->c_uid = current_fsuid(); cii->c_cached_perm = mask; } else cii->c_cached_perm |= mask; spin_unlock(&cii->c_lock); } /* remove cached acl from an inode */ void coda_cache_clear_inode(struct inode *inode) { struct coda_inode_info *cii = ITOC(inode); spin_lock(&cii->c_lock); cii->c_cached_epoch = atomic_read(&permission_epoch) - 1; spin_unlock(&cii->c_lock); } /* remove all acl caches */ void coda_cache_clear_all(struct super_block *sb) { atomic_inc(&permission_epoch); } /* check if the mask has been matched against the acl already */ int coda_cache_check(struct inode *inode, int mask) { struct coda_inode_info *cii = ITOC(inode); int hit; spin_lock(&cii->c_lock); hit = (mask & cii->c_cached_perm) == mask && uid_eq(cii->c_uid, current_fsuid()) && cii->c_cached_epoch == atomic_read(&permission_epoch); spin_unlock(&cii->c_lock); return hit; } /* Purging dentries and children */ /* The following routines drop dentries which are not in use and flag dentries which are in use to be zapped later. The flags are detected by: - coda_dentry_revalidate (for lookups) if the flag is C_PURGE - coda_dentry_delete: to remove dentry from the cache when d_count falls to zero - an inode method coda_revalidate (for attributes) if the flag is C_VATTR */ /* this won't do any harm: just flag all children */ static void coda_flag_children(struct dentry *parent, int flag) { struct dentry *de; spin_lock(&parent->d_lock); list_for_each_entry(de, &parent->d_subdirs, d_child) { /* don't know what to do with negative dentries */ if (d_inode(de) ) coda_flag_inode(d_inode(de), flag); } spin_unlock(&parent->d_lock); return; } void coda_flag_inode_children(struct inode *inode, int flag) { struct dentry *alias_de; if ( !inode || !S_ISDIR(inode->i_mode)) return; alias_de = d_find_alias(inode); if (!alias_de) return; coda_flag_children(alias_de, flag); shrink_dcache_parent(alias_de); dput(alias_de); } 9c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>root/include/uapi/sound/asequencer.h
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authorSteven Rostedt (VMware) <rostedt@goodmis.org>2017-01-30 19:27:10 -0500
committerSteven Rostedt (VMware) <rostedt@goodmis.org>2017-01-31 09:13:49 -0500
commit79c6f448c8b79c321e4a1f31f98194e4f6b6cae7 (patch)
tree370efda701f03cccf21e02bb1fdd3b852547d75c /include/uapi/sound/asequencer.h
parent0c744ea4f77d72b3dcebb7a8f2684633ec79be88 (diff)
tracing: Fix hwlat kthread migration
The hwlat tracer creates a kernel thread at start of the tracer. It is pinned to a single CPU and will move to the next CPU after each period of running. If the user modifies the migration thread's affinity, it will not change after that happens. The original code created the thread at the first instance it was called, but later was changed to destroy the thread after the tracer was finished, and would not be created until the next instance of the tracer was established. The code that initialized the affinity was only called on the initial instantiation of the tracer. After that, it was not initialized, and the previous affinity did not match the current newly created one, making it appear that the user modified the thread's affinity when it did not, and the thread failed to migrate again. Cc: stable@vger.kernel.org Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'include/uapi/sound/asequencer.h')