From 6aa7de059173a986114ac43b8f50b297a86f09a8 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Mon, 23 Oct 2017 14:07:29 -0700 Subject: locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland Signed-off-by: Paul E. McKenney Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar --- sound/firewire/amdtp-stream.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) (limited to 'sound/firewire/amdtp-stream.c') diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c index 3fc581a5ad62..4a1dc145327b 100644 --- a/sound/firewire/amdtp-stream.c +++ b/sound/firewire/amdtp-stream.c @@ -376,7 +376,7 @@ static void update_pcm_pointers(struct amdtp_stream *s, ptr = s->pcm_buffer_pointer + frames; if (ptr >= pcm->runtime->buffer_size) ptr -= pcm->runtime->buffer_size; - ACCESS_ONCE(s->pcm_buffer_pointer) = ptr; + WRITE_ONCE(s->pcm_buffer_pointer, ptr); s->pcm_period_pointer += frames; if (s->pcm_period_pointer >= pcm->runtime->period_size) { @@ -388,7 +388,7 @@ static void update_pcm_pointers(struct amdtp_stream *s, static void pcm_period_tasklet(unsigned long data) { struct amdtp_stream *s = (void *)data; - struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm); + struct snd_pcm_substream *pcm = READ_ONCE(s->pcm); if (pcm) snd_pcm_period_elapsed(pcm); @@ -453,7 +453,7 @@ static int handle_out_packet(struct amdtp_stream *s, s->data_block_counter = (s->data_block_counter + data_blocks) & 0xff; - buffer[0] = cpu_to_be32(ACCESS_ONCE(s->source_node_id_field) | + buffer[0] = cpu_to_be32(READ_ONCE(s->source_node_id_field) | (s->data_block_quadlets << CIP_DBS_SHIFT) | ((s->sph << CIP_SPH_SHIFT) & CIP_SPH_MASK) | s->data_block_counter); @@ -472,7 +472,7 @@ static int handle_out_packet(struct amdtp_stream *s, if (queue_out_packet(s, payload_length) < 0) return -EIO; - pcm = ACCESS_ONCE(s->pcm); + pcm = READ_ONCE(s->pcm); if (pcm && pcm_frames > 0) update_pcm_pointers(s, pcm, pcm_frames); @@ -504,7 +504,7 @@ static int handle_out_packet_without_header(struct amdtp_stream *s, if (queue_out_packet(s, payload_length) < 0) return -EIO; - pcm = ACCESS_ONCE(s->pcm); + pcm = READ_ONCE(s->pcm); if (pcm && pcm_frames > 0) update_pcm_pointers(s, pcm, pcm_frames); @@ -621,7 +621,7 @@ end: if (queue_in_packet(s) < 0) return -EIO; - pcm = ACCESS_ONCE(s->pcm); + pcm = READ_ONCE(s->pcm); if (pcm && pcm_frames > 0) update_pcm_pointers(s, pcm, pcm_frames); @@ -649,7 +649,7 @@ static int handle_in_packet_without_header(struct amdtp_stream *s, if (queue_in_packet(s) < 0) return -EIO; - pcm = ACCESS_ONCE(s->pcm); + pcm = READ_ONCE(s->pcm); if (pcm && pcm_frames > 0) update_pcm_pointers(s, pcm, pcm_frames); @@ -947,7 +947,7 @@ unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s) if (!in_interrupt() && amdtp_stream_running(s)) fw_iso_context_flush_completions(s->context); - return ACCESS_ONCE(s->pcm_buffer_pointer); + return READ_ONCE(s->pcm_buffer_pointer); } EXPORT_SYMBOL(amdtp_stream_pcm_pointer); @@ -977,9 +977,8 @@ EXPORT_SYMBOL(amdtp_stream_pcm_ack); void amdtp_stream_update(struct amdtp_stream *s) { /* Precomputing. */ - ACCESS_ONCE(s->source_node_id_field) = - (fw_parent_device(s->unit)->card->node_id << CIP_SID_SHIFT) & - CIP_SID_MASK; + WRITE_ONCE(s->source_node_id_field, + (fw_parent_device(s->unit)->card->node_id << CIP_SID_SHIFT) & CIP_SID_MASK); } EXPORT_SYMBOL(amdtp_stream_update); @@ -1022,7 +1021,7 @@ void amdtp_stream_pcm_abort(struct amdtp_stream *s) { struct snd_pcm_substream *pcm; - pcm = ACCESS_ONCE(s->pcm); + pcm = READ_ONCE(s->pcm); if (pcm) snd_pcm_stop_xrun(pcm); } -- cgit