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0a53b203f

Matt Whitlock

2014-03-23

SUCCESS Duration: 157s

Subject

add discard option -d to swapon

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No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

util-linux/Config.src +9 -0 util-linux/swaponoff.c +76 -9

util-linux/Config.src+9 -0

@@ -599,6 +599,15 @@ config SWAPONOFF
	space. If you are not using any swap space, you can leave this
	option disabled.

+	config FEATURE_SWAPON_DISCARD
+	bool "Support discard option -d"
+	default y
+	depends on SWAPONOFF
+	help
+	Enable support for discarding swap area blocks at swapon and/or as
+	the kernel frees them. This option enables both the -d option on
+	'swapon' and the 'discard' option for swap entries in /etc/fstab.
+
	config FEATURE_SWAPON_PRI
	bool "Support priority option -p"
	default y

util-linux/swaponoff.c+76 -9

@@ -8,10 +8,14 @@
	*/

	//usage:#define swapon_trivial_usage
-	//usage: "[-a]" IF_FEATURE_SWAPON_PRI(" [-p PRI]") " [DEVICE]"
+	//usage: "[-a]" IF_FEATURE_SWAPON_DISCARD(" [-d[POL]]") IF_FEATURE_SWAPON_PRI(" [-p PRI]") " [DEVICE]"
	//usage:#define swapon_full_usage "\n\n"
	//usage: "Start swapping on DEVICE\n"
	//usage: "\n -a Start swapping on all swap devices"
+	//usage: IF_FEATURE_SWAPON_DISCARD(
+	//usage: "\n -d[POL] Discard blocks at swapon (POL=once),"
+	//usage: "\n as freed (POL=pages), or both (POL omitted)"
+	//usage: )
	//usage: IF_FEATURE_SWAPON_PRI(
	//usage: "\n -p PRI Set swap device priority"
	//usage: )
@@ -38,7 +42,22 @@
	# define MNTTYPE_SWAP "swap"
	#endif

-	#if ENABLE_FEATURE_SWAPON_PRI
+	#if ENABLE_FEATURE_SWAPON_DISCARD
+	#ifndef SWAP_FLAG_DISCARD
+	#define SWAP_FLAG_DISCARD 0x10000
+	#endif
+	#ifndef SWAP_FLAG_DISCARD_ONCE
+	#define SWAP_FLAG_DISCARD_ONCE 0x20000
+	#endif
+	#ifndef SWAP_FLAG_DISCARD_PAGES
+	#define SWAP_FLAG_DISCARD_PAGES 0x40000
+	#endif
+	#define SWAP_FLAG_DISCARD_MASK \
+	(SWAP_FLAG_DISCARD \| SWAP_FLAG_DISCARD_ONCE \| SWAP_FLAG_DISCARD_PAGES)
+	#endif
+
+
+	#if ENABLE_FEATURE_SWAPON_DISCARD \|\| ENABLE_FEATURE_SWAPON_PRI
	struct globals {
	int flags;
	} FIX_ALIASING;
@@ -98,9 +117,23 @@ static int do_em_all(void)
	if (applet_name[5] != 'n'
	\|\| hasmntopt(m, MNTOPT_NOAUTO) == NULL
	) {
-	#if ENABLE_FEATURE_SWAPON_PRI
+	#if ENABLE_FEATURE_SWAPON_DISCARD \|\| ENABLE_FEATURE_SWAPON_PRI
	char *p;
	g_flags = cl_flags; /* each swap space might have different flags */
+	#if ENABLE_FEATURE_SWAPON_DISCARD
+	p = hasmntopt(m, "discard");
+	if (p) {
+	if (p[7] == '=') {
+	if (strncmp(p + 8, "once", 4) == 0 && (p[12] == ',' \|\| p[12] == '\0'))
+	g_flags = (g_flags & ~SWAP_FLAG_DISCARD_MASK) \| SWAP_FLAG_DISCARD \| SWAP_FLAG_DISCARD_ONCE;
+	else if (strncmp(p + 8, "pages", 5) == 0 && (p[13] == ',' \|\| p[13] == '\0'))
+	g_flags = (g_flags & ~SWAP_FLAG_DISCARD_MASK) \| SWAP_FLAG_DISCARD \| SWAP_FLAG_DISCARD_PAGES;
+	}
+	else if (p[7] == ',' \|\| p[7] == '\0')
+	g_flags = (g_flags & ~SWAP_FLAG_DISCARD_MASK) \| SWAP_FLAG_DISCARD;
+	}
+	#endif
+	#if ENABLE_FEATURE_SWAPON_PRI
	p = hasmntopt(m, "pri");
	if (p) {
	/* Max allowed 32767 (== SWAP_FLAG_PRIO_MASK) */
@@ -111,6 +144,7 @@ static int do_em_all(void)
	MIN(prio, SWAP_FLAG_PRIO_MASK);
	}
	}
+	#endif
	#endif
	err += swap_enable_disable(m->mnt_fsname);
	}
@@ -127,24 +161,57 @@ int swap_on_off_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
	int swap_on_off_main(int argc UNUSED_PARAM, char **argv)
	{
	int ret;
+	#if ENABLE_FEATURE_SWAPON_DISCARD
+	char *discard = NULL;
+	#endif
	#if ENABLE_FEATURE_SWAPON_PRI
	unsigned prio;
	#endif

	INIT_G();

-	#if !ENABLE_FEATURE_SWAPON_PRI
+	#if !ENABLE_FEATURE_SWAPON_DISCARD && !ENABLE_FEATURE_SWAPON_PRI
	ret = getopt32(argv, "a");
	#else
+	#if ENABLE_FEATURE_SWAPON_PRI
	if (applet_name[5] == 'n')
	opt_complementary = "p+";
-	ret = getopt32(argv, (applet_name[5] == 'n') ? "ap:" : "a", &prio);
+	#endif
+	ret = getopt32(argv, (applet_name[5] == 'n') ?
+	#if ENABLE_FEATURE_SWAPON_DISCARD
+	"d::"
+	#endif
+	#if ENABLE_FEATURE_SWAPON_PRI
+	"p:"
+	#endif
+	"a" : "a"
+	#if ENABLE_FEATURE_SWAPON_DISCARD
+	, &discard
+	#endif
+	#if ENABLE_FEATURE_SWAPON_PRI
+	, &prio
+	#endif
+	);
+	#endif

-	if (ret & 2) { // -p
-	g_flags = SWAP_FLAG_PREFER \|
-	MIN(prio, SWAP_FLAG_PRIO_MASK);
-	ret &= 1;
+	#if ENABLE_FEATURE_SWAPON_DISCARD
+	if (ret & 1) { // -d
+	if (!discard)
+	g_flags \|= SWAP_FLAG_DISCARD;
+	else if (strcmp(discard, "once") == 0)
+	g_flags \|= SWAP_FLAG_DISCARD \| SWAP_FLAG_DISCARD_ONCE;
+	else if (strcmp(discard, "pages") == 0)
+	g_flags \|= SWAP_FLAG_DISCARD \| SWAP_FLAG_DISCARD_PAGES;
+	else
+	bb_show_usage();
	}
+	ret >>= 1;
+	#endif
+	#if ENABLE_FEATURE_SWAPON_PRI
+	if (ret & 1) // -p
+	g_flags \|= SWAP_FLAG_PREFER \|
+	MIN(prio, SWAP_FLAG_PRIO_MASK);
+	ret >>= 1;
	#endif

	if (ret /* & 1: not needed */) // -a