msm: ipc_logging: Replace spinlock_t with rwlock_t
Currently with the spinlock, all drivers are serialized(SMD_PKT,
BAM_DMUX etc.) when they try to log into the IPC logging even though the
drivers log into their own context space. The read/write lock will
enable multiple drivers to log into their context space in parallel.
This will help more in the case of drivers which are
performance-critical like BAM_DMUX.
ipc_log_context_list is read often and updated rarely so replace the
usage of spinlock_t with rwlock_t.
Change-Id: I91f18ef67b80edf6f045f93f51ad2f48e46b3bb4
Signed-off-by: Arun Kumar Neelakantam <aneela@codeaurora.org>
diff --git a/arch/arm/mach-msm/ipc_logging.c b/arch/arm/mach-msm/ipc_logging.c
index 1260a1a..280f237 100644
--- a/arch/arm/mach-msm/ipc_logging.c
+++ b/arch/arm/mach-msm/ipc_logging.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
@@ -32,7 +32,7 @@
#include "ipc_logging.h"
static LIST_HEAD(ipc_log_context_list);
-DEFINE_SPINLOCK(ipc_log_context_list_lock);
+DEFINE_RWLOCK(ipc_log_context_list_lock);
static atomic_t next_log_id = ATOMIC_INIT(0);
static struct ipc_log_page *get_first_page(struct ipc_log_context *ilctxt)
@@ -140,7 +140,7 @@
return;
}
- spin_lock_irqsave(&ipc_log_context_list_lock, flags);
+ read_lock_irqsave(&ipc_log_context_list_lock, flags);
spin_lock(&ilctxt->ipc_log_context_lock);
while (ilctxt->write_avail < ectxt->offset)
msg_read(ilctxt, NULL);
@@ -165,7 +165,7 @@
ilctxt->write_avail -= ectxt->offset;
complete(&ilctxt->read_avail);
spin_unlock(&ilctxt->ipc_log_context_lock);
- spin_unlock_irqrestore(&ipc_log_context_list_lock, flags);
+ read_unlock_irqrestore(&ipc_log_context_list_lock, flags);
}
EXPORT_SYMBOL(ipc_log_write);
@@ -471,13 +471,13 @@
if (!df_info)
return -ENOSPC;
- spin_lock_irqsave(&ipc_log_context_list_lock, flags);
+ read_lock_irqsave(&ipc_log_context_list_lock, flags);
spin_lock(&ilctxt->ipc_log_context_lock);
df_info->type = type;
df_info->dfunc = dfunc;
list_add_tail(&df_info->list, &ilctxt->dfunc_info_list);
spin_unlock(&ilctxt->ipc_log_context_lock);
- spin_unlock_irqrestore(&ipc_log_context_list_lock, flags);
+ read_unlock_irqrestore(&ipc_log_context_list_lock, flags);
return 0;
}
EXPORT_SYMBOL(add_deserialization_func);
@@ -528,9 +528,9 @@
create_ctx_debugfs(ctxt, mod_name);
- spin_lock_irqsave(&ipc_log_context_list_lock, flags);
+ write_lock_irqsave(&ipc_log_context_list_lock, flags);
list_add_tail(&ctxt->list, &ipc_log_context_list);
- spin_unlock_irqrestore(&ipc_log_context_list_lock, flags);
+ write_unlock_irqrestore(&ipc_log_context_list_lock, flags);
return (void *)ctxt;
release_ipc_log_context:
diff --git a/arch/arm/mach-msm/ipc_logging.h b/arch/arm/mach-msm/ipc_logging.h
index 0eb82a5..36b4171 100644
--- a/arch/arm/mach-msm/ipc_logging.h
+++ b/arch/arm/mach-msm/ipc_logging.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
@@ -65,7 +65,7 @@
#define IS_MSG_TYPE(x) (((x) > TSV_TYPE_MSG_START) && \
((x) < TSV_TYPE_MSG_END))
-extern spinlock_t ipc_log_context_list_lock;
+extern rwlock_t ipc_log_context_list_lock;
extern int msg_read(struct ipc_log_context *ilctxt,
struct encode_context *ectxt);
diff --git a/arch/arm/mach-msm/ipc_logging_debug.c b/arch/arm/mach-msm/ipc_logging_debug.c
index ff947ef..246fb99 100644
--- a/arch/arm/mach-msm/ipc_logging_debug.c
+++ b/arch/arm/mach-msm/ipc_logging_debug.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
@@ -62,7 +62,7 @@
dctxt.output_format = OUTPUT_DEBUGFS;
dctxt.buff = buff;
dctxt.size = size;
- spin_lock_irqsave(&ipc_log_context_list_lock, flags);
+ read_lock_irqsave(&ipc_log_context_list_lock, flags);
spin_lock(&ilctxt->ipc_log_context_lock);
while (dctxt.size >= MAX_MSG_DECODED_SIZE &&
!is_ilctxt_empty(ilctxt)) {
@@ -70,19 +70,19 @@
deserialize_func = get_deserialization_func(ilctxt,
ectxt.hdr.type);
spin_unlock(&ilctxt->ipc_log_context_lock);
- spin_unlock_irqrestore(&ipc_log_context_list_lock, flags);
+ read_unlock_irqrestore(&ipc_log_context_list_lock, flags);
if (deserialize_func)
deserialize_func(&ectxt, &dctxt);
else
pr_err("%s: unknown message 0x%x\n",
__func__, ectxt.hdr.type);
- spin_lock_irqsave(&ipc_log_context_list_lock, flags);
+ read_lock_irqsave(&ipc_log_context_list_lock, flags);
spin_lock(&ilctxt->ipc_log_context_lock);
}
if ((size - dctxt.size) == 0)
init_completion(&ilctxt->read_avail);
spin_unlock(&ilctxt->ipc_log_context_lock);
- spin_unlock_irqrestore(&ipc_log_context_list_lock, flags);
+ read_unlock_irqrestore(&ipc_log_context_list_lock, flags);
return size - dctxt.size;
}