powerpc: vdso fixes

PATCH New Benjamin Herrenschmidt 1 participant 1 message Nov 13, 2005 PowerPC

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Benjamin Herrenschmidt

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2005-11-13 00:27 UTC #0 lore raw

PATCH 1/1 powerpc: vdso fixes

This fixes various errors in the new functions added in the vDSO's, I've been able to test the 32 bits version and I get consistent results with the corresponding syscalls.

There is still a question about get_tbfreq() though. It currently returns the value that the kernel keeps in tb_ticks_per_sec. This value is obtained from the timebase at boot, but it's truncated to HZ precision:

	tb_ticks_per_jiffy = ppc_tb_freq / HZ;
	tb_ticks_per_sec = tb_ticks_per_jiffy * HZ;

And it's later on modified by the ppc_adjtimex() code.

This is different from the value exposed in /proc/cpuinfo for the timebase which is a straight copy of ppc_tb_freq, which is the calibration value obtained at boot and unmodified.

The question at this point are: Is that "rouding" to HZ done by the kernel correct ? And should the vDSO return this value that gets adjusted or the fixed initial calibration value, or both.

In the later case, should I add an argument to get_tbfreq() or add a separate function ?

In the meantime, please apply this patch as it fixes a few annoying bug in the vDSO implementation currently in -rc1.

Signed-off-by Benjamin Herrenschmidt <[email protected]>

arch/powerpc/kernel/asm-offsets.c +2 -2

Index: linux-work/arch/powerpc/kernel/asm-offsets.c
===================================================================
@@ -275,8 +275,8 @@
 #else
 	DEFINE(TVAL32_TV_SEC, offsetof(struct timeval, tv_sec));
 	DEFINE(TVAL32_TV_USEC, offsetof(struct timeval, tv_usec));
-	DEFINE(TSPEC32_TV_SEC, offsetof(struct timespec, tv_sec));
-	DEFINE(TSPEC32_TV_NSEC, offsetof(struct timespec, tv_nsec));
+	DEFINE(TSPC32_TV_SEC, offsetof(struct timespec, tv_sec));
+	DEFINE(TSPC32_TV_NSEC, offsetof(struct timespec, tv_nsec));
 #endif
 	/* timeval/timezone offsets for use by vdso */
 	DEFINE(TZONE_TZ_MINWEST, offsetof(struct timezone, tz_minuteswest));

arch/powerpc/kernel/vdso32/gettimeofday.S +3 -3

Index: linux-work/arch/powerpc/kernel/vdso32/gettimeofday.S
===================================================================
@@ -83,7 +83,7 @@
 	/* Check for supported clock IDs */
 	cmpli	cr0,r3,CLOCK_REALTIME
 	cmpli	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0,cr0,cr1
+	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
 	bne	cr0,99f
 
 	mflr	r12			/* r12 saves lr */

@@ -91,7 +91,7 @@
 	mr	r10,r3			/* r10 saves id */
 	mr	r11,r4			/* r11 saves tp */
 	bl	__get_datapage@local	/* get data page */
-	mr	r9, r3			/* datapage ptr in r9 */
+	mr	r9,r3			/* datapage ptr in r9 */
 	beq	cr1,50f			/* if monotonic -> jump there */
 
 	/*

@@ -210,7 +210,7 @@
 	/* Check for supported clock IDs */
 	cmpwi	cr0,r3,CLOCK_REALTIME
 	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0,cr0,cr1
+	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
 	bne	cr0,99f
 
 	li	r3,0

arch/powerpc/kernel/vdso64/gettimeofday.S +2 -2

Index: linux-work/arch/powerpc/kernel/vdso64/gettimeofday.S
===================================================================
@@ -68,7 +68,7 @@
 	/* Check for supported clock IDs */
 	cmpwi	cr0,r3,CLOCK_REALTIME
 	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0,cr0,cr1
+	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
 	bne	cr0,99f
 
 	mflr	r12			/* r12 saves lr */

@@ -181,7 +181,7 @@
 	/* Check for supported clock IDs */
 	cmpwi	cr0,r3,CLOCK_REALTIME
 	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0,cr0,cr1
+	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
 	bne	cr0,99f
 
 	li	r3,0

arch/powerpc/kernel/vdso32/datapage.S +2 -1

Index: linux-work/arch/powerpc/kernel/vdso32/datapage.S
===================================================================
@@ -77,8 +77,9 @@
 	mflr	r12
   .cfi_register lr,r12
 	bl	__get_datapage@local
-	lwz	r3,CFG_TB_TICKS_PER_SEC(r3)
 	lwz	r4,(CFG_TB_TICKS_PER_SEC + 4)(r3)
+	lwz	r3,CFG_TB_TICKS_PER_SEC(r3)
 	mtlr	r12
+	blr
   .cfi_endproc
 V_FUNCTION_END(__kernel_get_tbfreq)

arch/powerpc/kernel/vdso64/datapage.S +1 -0

Index: linux-work/arch/powerpc/kernel/vdso64/datapage.S
===================================================================
@@ -80,5 +80,6 @@
 	bl	V_LOCAL_FUNC(__get_datapage)
 	ld	r3,CFG_TB_TICKS_PER_SEC(r3)
 	mtlr	r12
+	blr
   .cfi_endproc
 V_FUNCTION_END(__kernel_get_tbfreq)