summaryrefslogtreecommitdiffstats
path: root/sound/core/seq/oss/seq_oss_writeq.c
AgeCommit message (Collapse)AuthorFilesLines
2021-06-09ALSA: seq: Fix assignment in if conditionTakashi Iwai1-1/+2
There are lots of places doing assignments in if condition in ALSA sequencer core, which is a bad coding style that may confuse readers and occasionally lead to bugs. This patch is merely for coding-style fixes, no functional changes. Link: https://lore.kernel.org/r/20210608140540.17885-57-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156Thomas Gleixner1-14/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-12ALSA: seq: Simplify snd_seq_kernel_client_enqueue() helperTakashi Iwai1-1/+1
We have two helpers for queuing a sequencer event from the kernel client, and both are used only from OSS sequencer layer without any hop and atomic set. Let's simplify and unify two helpers into one. No functional change, just a call pattern change. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar1-0/+1
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-09ALSA: seq_oss: fix waitqueue_active without memory barrier in snd-seq-ossKosuke Tatsukawa1-3/+1
snd_seq_oss_readq_put_event() seems to be missing a memory barrier which might cause the waker to not notice the waiter and miss sending a wake_up as in the following figure. snd_seq_oss_readq_put_event snd_seq_oss_readq_wait ------------------------------------------------------------------------ /* wait_event_interruptible_timeout */ /* __wait_event_interruptible_timeout */ /* ___wait_event */ for (;;) { prepare_to_wait_event(&wq, &__wait, state); spin_lock_irqsave(&q->lock, flags); if (waitqueue_active(&q->midi_sleep)) /* The CPU might reorder the test for the waitqueue up here, before prior writes complete */ if ((q->qlen>0 || q->head==q->tail) ... __ret = schedule_timeout(__ret) if (q->qlen >= q->maxlen - 1) { memcpy(&q->q[q->tail], ev, sizeof(*ev)); q->tail = (q->tail + 1) % q->maxlen; q->qlen++; ------------------------------------------------------------------------ There are two other place in sound/core/seq/oss/ which have similar code. The attached patch removes the call to waitqueue_active() leaving just wake_up() behind. This fixes the problem because the call to spin_lock_irqsave() in wake_up() will be an ACQUIRE operation. I found this issue when I was looking through the linux source code for places calling waitqueue_active() before wake_up*(), but without preceding memory barriers, after sending a patch to fix a similar issue in drivers/tty/n_tty.c (Details about the original issue can be found here: https://lkml.org/lkml/2015/9/28/849). Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2007-10-16[ALSA] seq: resource leak fix and various code cleanupsEugene Teo1-2/+4
This patch fixes: 1) a resource leak (CID: 1817) 2) various code cleanups Signed-off-by: Eugene Teo <eugeneteo@kernel.sg> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
2006-01-03[ALSA] Remove xxx_t typedefs: Sequencer OSS-emulationTakashi Iwai1-17/+17
Modules: ALSA<-OSS sequencer,ALSA sequencer Remove xxx_t typedefs from the core sequencer OSS-emulation codes. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2005-09-12[ALSA] Replace with kzalloc() - seq stuffTakashi Iwai1-1/+1
ALSA sequencer,Instrument layer,ALSA<-OSS sequencer Replace kcalloc(1,..) with kzalloc(). Signed-off-by: Takashi Iwai <tiwai@suse.de>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+170
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!