From: Samuel Thibault <samuel.thibault@ens-lyon.org>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] [PATCH] Save 3MB ioport table memory
Date: Mon, 21 Jul 2008 13:02:11 +0100 [thread overview]
Message-ID: <20080721120211.GD4501@implementation.uk.xensource.com> (raw)
Hello,
On 64bit machines, qemu uses 3MB of memory for the ioport tables, while
the actual use of them is quite sparse. The patch below saves that
memory by leaving them zeroed and just test for that and use the default
pointer.
Samuel
Index: vl.c
===================================================================
--- vl.c (révision 4917)
+++ vl.c (copie de travail)
@@ -279,17 +279,29 @@
static uint32_t default_ioport_readw(void *opaque, uint32_t address)
{
uint32_t data;
- data = ioport_read_table[0][address](ioport_opaque[address], address);
+ IOPortReadFunc *func = ioport_read_table[0][address];
+ if (!func)
+ func = default_ioport_readb;
+ data = func(ioport_opaque[address], address);
address = (address + 1) & (MAX_IOPORTS - 1);
- data |= ioport_read_table[0][address](ioport_opaque[address], address) << 8;
+ func = ioport_read_table[0][address];
+ if (!func)
+ func = default_ioport_readb;
+ data |= func(ioport_opaque[address], address) << 8;
return data;
}
static void default_ioport_writew(void *opaque, uint32_t address, uint32_t data)
{
- ioport_write_table[0][address](ioport_opaque[address], address, data & 0xff);
+ IOPortWriteFunc *func = ioport_write_table[0][address];
+ if (!func)
+ func = default_ioport_writeb;
+ func(ioport_opaque[address], address, data & 0xff);
address = (address + 1) & (MAX_IOPORTS - 1);
- ioport_write_table[0][address](ioport_opaque[address], address, (data >> 8) & 0xff);
+ func = ioport_write_table[0][address];
+ if (!func)
+ func = default_ioport_writeb;
+ func(ioport_opaque[address], address, (data >> 8) & 0xff);
}
static uint32_t default_ioport_readl(void *opaque, uint32_t address)
@@ -309,16 +321,6 @@
static void init_ioports(void)
{
- int i;
-
- for(i = 0; i < MAX_IOPORTS; i++) {
- ioport_read_table[0][i] = default_ioport_readb;
- ioport_write_table[0][i] = default_ioport_writeb;
- ioport_read_table[1][i] = default_ioport_readw;
- ioport_write_table[1][i] = default_ioport_writew;
- ioport_read_table[2][i] = default_ioport_readl;
- ioport_write_table[2][i] = default_ioport_writel;
- }
}
/* size is the word size in byte */
@@ -390,11 +392,14 @@
void cpu_outb(CPUState *env, int addr, int val)
{
+ IOPortWriteFunc *func = ioport_write_table[0][addr];
+ if (!func)
+ func = default_ioport_writeb;
#ifdef DEBUG_IOPORT
if (loglevel & CPU_LOG_IOPORT)
fprintf(logfile, "outb: %04x %02x\n", addr, val);
#endif
- ioport_write_table[0][addr](ioport_opaque[addr], addr, val);
+ func(ioport_opaque[addr], addr, val);
#ifdef USE_KQEMU
if (env)
env->last_io_time = cpu_get_time_fast();
@@ -403,11 +408,14 @@
void cpu_outw(CPUState *env, int addr, int val)
{
+ IOPortWriteFunc *func = ioport_write_table[1][addr];
+ if (!func)
+ func = default_ioport_writew;
#ifdef DEBUG_IOPORT
if (loglevel & CPU_LOG_IOPORT)
fprintf(logfile, "outw: %04x %04x\n", addr, val);
#endif
- ioport_write_table[1][addr](ioport_opaque[addr], addr, val);
+ func(ioport_opaque[addr], addr, val);
#ifdef USE_KQEMU
if (env)
env->last_io_time = cpu_get_time_fast();
@@ -416,11 +424,14 @@
void cpu_outl(CPUState *env, int addr, int val)
{
+ IOPortWriteFunc *func = ioport_write_table[2][addr];
+ if (!func)
+ func = default_ioport_writel;
#ifdef DEBUG_IOPORT
if (loglevel & CPU_LOG_IOPORT)
fprintf(logfile, "outl: %04x %08x\n", addr, val);
#endif
- ioport_write_table[2][addr](ioport_opaque[addr], addr, val);
+ func(ioport_opaque[addr], addr, val);
#ifdef USE_KQEMU
if (env)
env->last_io_time = cpu_get_time_fast();
@@ -430,7 +441,10 @@
int cpu_inb(CPUState *env, int addr)
{
int val;
- val = ioport_read_table[0][addr](ioport_opaque[addr], addr);
+ IOPortReadFunc *func = ioport_read_table[0][addr];
+ if (!func)
+ func = default_ioport_readb;
+ val = func(ioport_opaque[addr], addr);
#ifdef DEBUG_IOPORT
if (loglevel & CPU_LOG_IOPORT)
fprintf(logfile, "inb : %04x %02x\n", addr, val);
@@ -445,7 +459,10 @@
int cpu_inw(CPUState *env, int addr)
{
int val;
- val = ioport_read_table[1][addr](ioport_opaque[addr], addr);
+ IOPortReadFunc *func = ioport_read_table[1][addr];
+ if (!func)
+ func = default_ioport_readw;
+ val = func(ioport_opaque[addr], addr);
#ifdef DEBUG_IOPORT
if (loglevel & CPU_LOG_IOPORT)
fprintf(logfile, "inw : %04x %04x\n", addr, val);
@@ -460,7 +477,10 @@
int cpu_inl(CPUState *env, int addr)
{
int val;
- val = ioport_read_table[2][addr](ioport_opaque[addr], addr);
+ IOPortReadFunc *func = ioport_read_table[2][addr];
+ if (!func)
+ func = default_ioport_readl;
+ val = func(ioport_opaque[addr], addr);
#ifdef DEBUG_IOPORT
if (loglevel & CPU_LOG_IOPORT)
fprintf(logfile, "inl : %04x %08x\n", addr, val);
next reply other threads:[~2008-07-21 12:02 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-07-21 12:02 Samuel Thibault [this message]
2008-07-23 1:52 ` [Qemu-devel] [PATCH] Save 3MB ioport table memory Anthony Liguori
2008-07-23 10:58 ` Samuel Thibault
2008-07-23 12:15 ` Paul Brook
2008-07-23 12:39 ` Samuel Thibault
2008-07-23 15:21 ` Anthony Liguori
2008-07-23 15:50 ` Paul Brook
2008-07-23 16:11 ` Anthony Liguori
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20080721120211.GD4501@implementation.uk.xensource.com \
--to=samuel.thibault@ens-lyon.org \
--cc=qemu-devel@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).