[PATCH] reduce large oss_pcm stack usage

Randy.Dunlap (randy.dunlap@verizon.net)
Thu, 27 Feb 2003 22:29:09 -0800


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Hi,

Jaroslav, Please review and apply.
Patch applies to 2.5.63.
Builds cleanly.

description: reduce stack usage in snd_pcm_oss_change_params()
from 0x584 to < 0x100 bytes;

Thanks,
~Randy
--------------6BE4E7458710081763E379BC
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name="oss_pcm_stack.patch"
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filename="oss_pcm_stack.patch"

patch_name: oss_pcm_stack.patch
patch_version: 2003-02-27.22:19:29
author: Randy.Dunlap <rddunlap@osdl.org>
description: reduce stack usage in snd_pcm_oss_change_params()
from 0x584 to < 0x100 bytes;
product: Linux
product_versions: linux-2563
changelog: _
URL: _
requires: _
conflicts: _
maintainer: Jaroslav Kysela <perex@suse.cz>
diffstat: =
sound/core/oss/pcm_oss.c | 145 ++++++++++++++++++++++++++---------------------
1 files changed, 81 insertions(+), 64 deletions(-)

diff -Naur ./sound/core/oss/pcm_oss.c%STCK ./sound/core/oss/pcm_oss.c
--- ./sound/core/oss/pcm_oss.c%STCK Mon Feb 24 11:05:42 2003
+++ ./sound/core/oss/pcm_oss.c Thu Feb 27 22:16:24 2003
@@ -294,8 +294,8 @@
static int snd_pcm_oss_change_params(snd_pcm_substream_t *substream)
{
snd_pcm_runtime_t *runtime = substream->runtime;
- snd_pcm_hw_params_t params, sparams;
- snd_pcm_sw_params_t sw_params;
+ snd_pcm_hw_params_t *params, *sparams;
+ snd_pcm_sw_params_t *sw_params;
ssize_t oss_buffer_size, oss_period_size;
size_t oss_frame_size;
int err;
@@ -304,6 +304,15 @@
snd_mask_t sformat_mask;
snd_mask_t mask;

+ sw_params = kmalloc(sizeof(*sw_params), GFP_KERNEL);
+ params = kmalloc(sizeof(*params), GFP_KERNEL);
+ sparams = kmalloc(sizeof(*sparams), GFP_KERNEL);
+ if (!sw_params || !params || !sparams) {
+ snd_printd("No memory\n");
+ err = -ENOMEM;
+ goto failure;
+ }
+
if (atomic_read(&runtime->mmap_count)) {
direct = 1;
} else {
@@ -311,9 +320,9 @@
direct = (setup != NULL && setup->direct);
}

- _snd_pcm_hw_params_any(&sparams);
- _snd_pcm_hw_param_setinteger(&sparams, SNDRV_PCM_HW_PARAM_PERIODS);
- _snd_pcm_hw_param_min(&sparams, SNDRV_PCM_HW_PARAM_PERIODS, 2, 0);
+ _snd_pcm_hw_params_any(sparams);
+ _snd_pcm_hw_param_setinteger(sparams, SNDRV_PCM_HW_PARAM_PERIODS);
+ _snd_pcm_hw_param_min(sparams, SNDRV_PCM_HW_PARAM_PERIODS, 2, 0);
snd_mask_none(&mask);
if (atomic_read(&runtime->mmap_count))
snd_mask_set(&mask, SNDRV_PCM_ACCESS_MMAP_INTERLEAVED);
@@ -322,17 +331,18 @@
if (!direct)
snd_mask_set(&mask, SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
}
- err = snd_pcm_hw_param_mask(substream, &sparams, SNDRV_PCM_HW_PARAM_ACCESS, &mask);
+ err = snd_pcm_hw_param_mask(substream, sparams, SNDRV_PCM_HW_PARAM_ACCESS, &mask);
if (err < 0) {
snd_printd("No usable accesses\n");
- return -EINVAL;
+ err = -EINVAL;
+ goto failure;
}
- choose_rate(substream, &sparams, runtime->oss.rate);
- snd_pcm_hw_param_near(substream, &sparams, SNDRV_PCM_HW_PARAM_CHANNELS, runtime->oss.channels, 0);
+ choose_rate(substream, sparams, runtime->oss.rate);
+ snd_pcm_hw_param_near(substream, sparams, SNDRV_PCM_HW_PARAM_CHANNELS, runtime->oss.channels, 0);

format = snd_pcm_oss_format_from(runtime->oss.format);

- sformat_mask = *hw_param_mask(&sparams, SNDRV_PCM_HW_PARAM_FORMAT);
+ sformat_mask = *hw_param_mask(sparams, SNDRV_PCM_HW_PARAM_FORMAT);
if (direct)
sformat = format;
else
@@ -346,52 +356,53 @@
}
if (sformat > SNDRV_PCM_FORMAT_LAST) {
snd_printd("Cannot find a format!!!\n");
- return -EINVAL;
+ err = -EINVAL;
+ goto failure;
}
}
- err = _snd_pcm_hw_param_set(&sparams, SNDRV_PCM_HW_PARAM_FORMAT, sformat, 0);
- snd_assert(err >= 0, return err);
+ err = _snd_pcm_hw_param_set(sparams, SNDRV_PCM_HW_PARAM_FORMAT, sformat, 0);
+ snd_assert(err >= 0, goto failure);

if (direct) {
- params = sparams;
+ memcpy(params, sparams, sizeof(*params));
} else {
- _snd_pcm_hw_params_any(&params);
- _snd_pcm_hw_param_set(&params, SNDRV_PCM_HW_PARAM_ACCESS,
+ _snd_pcm_hw_params_any(params);
+ _snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_ACCESS,
SNDRV_PCM_ACCESS_RW_INTERLEAVED, 0);
- _snd_pcm_hw_param_set(&params, SNDRV_PCM_HW_PARAM_FORMAT,
+ _snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_FORMAT,
snd_pcm_oss_format_from(runtime->oss.format), 0);
- _snd_pcm_hw_param_set(&params, SNDRV_PCM_HW_PARAM_CHANNELS,
+ _snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_CHANNELS,
runtime->oss.channels, 0);
- _snd_pcm_hw_param_set(&params, SNDRV_PCM_HW_PARAM_RATE,
+ _snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_RATE,
runtime->oss.rate, 0);
pdprintf("client: access = %i, format = %i, channels = %i, rate = %i\n",
- params_access(&params), params_format(&params),
- params_channels(&params), params_rate(&params));
+ params_access(params), params_format(params),
+ params_channels(params), params_rate(params));
}
pdprintf("slave: access = %i, format = %i, channels = %i, rate = %i\n",
- params_access(&sparams), params_format(&sparams),
- params_channels(&sparams), params_rate(&sparams));
+ params_access(sparams), params_format(sparams),
+ params_channels(sparams), params_rate(sparams));

- oss_frame_size = snd_pcm_format_physical_width(params_format(&params)) *
- params_channels(&params) / 8;
+ oss_frame_size = snd_pcm_format_physical_width(params_format(params)) *
+ params_channels(params) / 8;

snd_pcm_oss_plugin_clear(substream);
if (!direct) {
/* add necessary plugins */
snd_pcm_oss_plugin_clear(substream);
if ((err = snd_pcm_plug_format_plugins(substream,
- &params,
- &sparams)) < 0) {
+ params,
+ sparams)) < 0) {
snd_printd("snd_pcm_plug_format_plugins failed: %i\n", err);
snd_pcm_oss_plugin_clear(substream);
- return err;
+ goto failure;
}
if (runtime->oss.plugin_first) {
snd_pcm_plugin_t *plugin;
- if ((err = snd_pcm_plugin_build_io(substream, &sparams, &plugin)) < 0) {
+ if ((err = snd_pcm_plugin_build_io(substream, sparams, &plugin)) < 0) {
snd_printd("snd_pcm_plugin_build_io failed: %i\n", err);
snd_pcm_oss_plugin_clear(substream);
- return err;
+ goto failure;
}
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
err = snd_pcm_plugin_append(plugin);
@@ -400,66 +411,66 @@
}
if (err < 0) {
snd_pcm_oss_plugin_clear(substream);
- return err;
+ goto failure;
}
}
}

- err = snd_pcm_oss_period_size(substream, &params, &sparams);
+ err = snd_pcm_oss_period_size(substream, params, sparams);
if (err < 0)
- return err;
+ goto failure;

n = snd_pcm_plug_slave_size(substream, runtime->oss.period_bytes / oss_frame_size);
- err = snd_pcm_hw_param_near(substream, &sparams, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, n, 0);
- snd_assert(err >= 0, return err);
+ err = snd_pcm_hw_param_near(substream, sparams, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, n, 0);
+ snd_assert(err >= 0, goto failure);

- err = snd_pcm_hw_param_near(substream, &sparams, SNDRV_PCM_HW_PARAM_PERIODS,
+ err = snd_pcm_hw_param_near(substream, sparams, SNDRV_PCM_HW_PARAM_PERIODS,
runtime->oss.periods, 0);
- snd_assert(err >= 0, return err);
+ snd_assert(err >= 0, goto failure);

snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DROP, 0);

- if ((err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_HW_PARAMS, &sparams)) < 0) {
+ if ((err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_HW_PARAMS, sparams)) < 0) {
snd_printd("HW_PARAMS failed: %i\n", err);
- return err;
+ goto failure;
}

- memset(&sw_params, 0, sizeof(sw_params));
+ memset(sw_params, 0, sizeof(*sw_params));
if (runtime->oss.trigger) {
- sw_params.start_threshold = 1;
+ sw_params->start_threshold = 1;
} else {
- sw_params.start_threshold = runtime->boundary;
+ sw_params->start_threshold = runtime->boundary;
}
if (atomic_read(&runtime->mmap_count))
- sw_params.stop_threshold = runtime->boundary;
+ sw_params->stop_threshold = runtime->boundary;
else
- sw_params.stop_threshold = runtime->buffer_size;
- sw_params.tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
- sw_params.period_step = 1;
- sw_params.sleep_min = 0;
- sw_params.avail_min = runtime->period_size;
- sw_params.xfer_align = 1;
- sw_params.silence_threshold = 0;
- sw_params.silence_size = 0;
+ sw_params->stop_threshold = runtime->buffer_size;
+ sw_params->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
+ sw_params->period_step = 1;
+ sw_params->sleep_min = 0;
+ sw_params->avail_min = runtime->period_size;
+ sw_params->xfer_align = 1;
+ sw_params->silence_threshold = 0;
+ sw_params->silence_size = 0;

- if ((err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_SW_PARAMS, &sw_params)) < 0) {
+ if ((err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_SW_PARAMS, sw_params)) < 0) {
snd_printd("SW_PARAMS failed: %i\n", err);
- return err;
+ goto failure;
}
runtime->control->avail_min = runtime->period_size;

- runtime->oss.periods = params_periods(&sparams);
- oss_period_size = snd_pcm_plug_client_size(substream, params_period_size(&sparams));
- snd_assert(oss_period_size >= 0, return -EINVAL);
+ runtime->oss.periods = params_periods(sparams);
+ oss_period_size = snd_pcm_plug_client_size(substream, params_period_size(sparams));
+ snd_assert(oss_period_size >= 0, err = -EINVAL; goto failure);
if (runtime->oss.plugin_first) {
err = snd_pcm_plug_alloc(substream, oss_period_size);
if (err < 0)
- return err;
+ goto failure;
}
oss_period_size *= oss_frame_size;

oss_buffer_size = oss_period_size * runtime->oss.periods;
- snd_assert(oss_buffer_size >= 0, return -EINVAL);
+ snd_assert(oss_buffer_size >= 0, err = -EINVAL; goto failure);

runtime->oss.period_bytes = oss_period_size;
runtime->oss.buffer_bytes = oss_buffer_size;
@@ -468,12 +479,12 @@
runtime->oss.period_bytes,
runtime->oss.buffer_bytes);
pdprintf("slave: period_size = %i, buffer_size = %i\n",
- params_period_size(&sparams),
- params_buffer_size(&sparams));
+ params_period_size(sparams),
+ params_buffer_size(sparams));

- runtime->oss.format = snd_pcm_oss_format_to(params_format(&params));
- runtime->oss.channels = params_channels(&params);
- runtime->oss.rate = params_rate(&params);
+ runtime->oss.format = snd_pcm_oss_format_to(params_format(params));
+ runtime->oss.channels = params_channels(params);
+ runtime->oss.rate = params_rate(params);

runtime->oss.params = 0;
runtime->oss.prepare = 1;
@@ -483,7 +494,13 @@
runtime->oss.buffer_used = 0;
if (runtime->dma_area)
snd_pcm_format_set_silence(runtime->format, runtime->dma_area, bytes_to_samples(runtime, runtime->dma_bytes));
- return 0;
+
+ err = 0;
+failure:
+ kfree(sw_params);
+ kfree(params);
+ kfree(sparams);
+ return err;
}

static int snd_pcm_oss_get_active_substream(snd_pcm_oss_file_t *pcm_oss_file, snd_pcm_substream_t **r_substream)

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