diff options
| -rw-r--r-- | fs/relayfs/relay.c | 35 | ||||
| -rw-r--r-- | include/linux/relayfs_fs.h | 8 |
2 files changed, 32 insertions, 11 deletions
diff --git a/fs/relayfs/relay.c b/fs/relayfs/relay.c index b9bb569032729e..2935a6ab8ffab6 100644 --- a/fs/relayfs/relay.c +++ b/fs/relayfs/relay.c @@ -86,7 +86,8 @@ static void buf_unmapped_default_callback(struct rchan_buf *buf, static struct dentry *create_buf_file_default_callback(const char *filename, struct dentry *parent, int mode, - struct rchan_buf *buf) + struct rchan_buf *buf, + int *is_global) { return relayfs_create_file(filename, parent, mode, &relayfs_file_operations, buf); @@ -170,14 +171,16 @@ static inline void __relay_reset(struct rchan_buf *buf, unsigned int init) void relay_reset(struct rchan *chan) { unsigned int i; + struct rchan_buf *prev = NULL; if (!chan) return; for (i = 0; i < NR_CPUS; i++) { - if (!chan->buf[i]) - continue; + if (!chan->buf[i] || chan->buf[i] == prev) + break; __relay_reset(chan->buf[i], 0); + prev = chan->buf[i]; } } @@ -188,18 +191,22 @@ void relay_reset(struct rchan *chan) */ static struct rchan_buf *relay_open_buf(struct rchan *chan, const char *filename, - struct dentry *parent) + struct dentry *parent, + int *is_global) { struct rchan_buf *buf; struct dentry *dentry; + if (*is_global) + return chan->buf[0]; + buf = relay_create_buf(chan); if (!buf) return NULL; /* Create file in fs */ dentry = chan->cb->create_buf_file(filename, parent, S_IRUSR, - buf); + buf, is_global); if (!dentry) { relay_destroy_buf(buf); return NULL; @@ -273,6 +280,7 @@ struct rchan *relay_open(const char *base_filename, unsigned int i; struct rchan *chan; char *tmpname; + int is_global = 0; if (!base_filename) return NULL; @@ -297,7 +305,8 @@ struct rchan *relay_open(const char *base_filename, for_each_online_cpu(i) { sprintf(tmpname, "%s%d", base_filename, i); - chan->buf[i] = relay_open_buf(chan, tmpname, parent); + chan->buf[i] = relay_open_buf(chan, tmpname, parent, + &is_global); chan->buf[i]->cpu = i; if (!chan->buf[i]) goto free_bufs; @@ -311,6 +320,8 @@ free_bufs: if (!chan->buf[i]) break; relay_close_buf(chan->buf[i]); + if (is_global) + break; } kfree(tmpname); @@ -420,14 +431,16 @@ void relay_destroy_channel(struct kref *kref) void relay_close(struct rchan *chan) { unsigned int i; + struct rchan_buf *prev = NULL; if (!chan) return; for (i = 0; i < NR_CPUS; i++) { - if (!chan->buf[i]) - continue; + if (!chan->buf[i] || chan->buf[i] == prev) + break; relay_close_buf(chan->buf[i]); + prev = chan->buf[i]; } if (chan->last_toobig) @@ -447,14 +460,16 @@ void relay_close(struct rchan *chan) void relay_flush(struct rchan *chan) { unsigned int i; + struct rchan_buf *prev = NULL; if (!chan) return; for (i = 0; i < NR_CPUS; i++) { - if (!chan->buf[i]) - continue; + if (!chan->buf[i] || chan->buf[i] == prev) + break; relay_switch_subbuf(chan->buf[i], 0); + prev = chan->buf[i]; } } diff --git a/include/linux/relayfs_fs.h b/include/linux/relayfs_fs.h index 8c21771058571f..30f45511b40dde 100644 --- a/include/linux/relayfs_fs.h +++ b/include/linux/relayfs_fs.h @@ -116,6 +116,7 @@ struct rchan_callbacks * @parent: the parent of the file to create * @mode: the mode of the file to create * @buf: the channel buffer + * @is_global: outparam - set non-zero if the buffer should be global * * Called during relay_open(), once for each per-cpu buffer, * to allow the client to create a file to be used to @@ -126,12 +127,17 @@ struct rchan_callbacks * The callback should return the dentry of the file created * to represent the relay buffer. * + * Setting the is_global outparam to a non-zero value will + * cause relay_open() to create a single global buffer rather + * than the default set of per-cpu buffers. + * * See Documentation/filesystems/relayfs.txt for more info. */ struct dentry *(*create_buf_file)(const char *filename, struct dentry *parent, int mode, - struct rchan_buf *buf); + struct rchan_buf *buf, + int *is_global); /* * remove_buf_file - remove file representing a relayfs channel buffer |