linux-toradex.git/lib/vdso, branch v7.0-rc6

vdso/gettimeofday: Force inlining of __cvdso_clock_getres_common()

2026-01-26T21:27:07+00:00

With CONFIG_CC_OPTIMIZE_FOR_SIZE=y, GCC may decide not to inline
__cvdso_clock_getres_common(). This introduces spurious internal
function calls in the vDSO fastpath.

Furthermore, with automatic stack variable initialization
(CONFIG_INIT_STACK_ALL_ZERO or CONFIG_INIT_STACK_ALL_PATTERN) GCC can emit
a call to memset() which is not valid in the vDSO.

Mark __cvdso_clock_getres_common() as __always_inline to avoid both issues.

Paradoxically the inlining even reduces the size of the code:

$ ./scripts/bloat-o-meter arch/powerpc/kernel/vdso/vgettimeofday-32.o.before arch/powerpc/kernel/vdso/vgettimeofday-32.o.after
add/remove: 0/1 grow/shrink: 1/1 up/down: 52/-148 (-96)
Function                                     old     new   delta
__c_kernel_clock_getres_time64                92     144     +52
__c_kernel_clock_getres                      136     132      -4
__cvdso_clock_getres_common                  144       -    -144
Total: Before=2788, After=2692, chg -3.44%

With CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y the functions are always inlined
and therefore the behaviour stays the same.

See also the equivalent change for clock_gettime() in commit b91c8c42ffdd
("lib/vdso: Force inlining of __cvdso_clock_gettime_common()").

Fixes: 21bbfd74044f ("x86/vdso: Provide clock_getres_time64() for x86-32")
Fixes: 1149dcdfc9ef ("ARM: VDSO: Provide clock_getres_time64()")
Fixes: f10c2e72b5de ("arm64: vdso32: Provide clock_getres_time64()")
Fixes: bec06cd6a140 ("MIPS: vdso: Provide getres_time64() for 32-bit ABIs")
Fixes: 759a1f97373f ("powerpc/vdso: Provide clock_getres_time64()")
Reported-by: Sverdlin, Alexander 
Suggested-by: Christophe Leroy (CS GROUP) 
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/lkml/230c749f-ebd6-4829-93ee-601d88000a45@kernel.org/
Link: https://patch.msgid.link/20260123-vdso-clock_getres-inline-v1-1-4d6203b90cd3@linutronix.de
Closes: https://lore.kernel.org/lkml/f45316f65a46da638b3c6aa69effd8980e6677b9.camel@siemens.com/

vdso: Gate VDSO_GETRANDOM behind HAVE_GENERIC_VDSO

2025-09-04T09:23:51+00:00

All architectures which want to implement getrandom() in the vDSO need to
use the generic vDSO library.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-11-d9b65750e49f@linutronix.de

vdso: Drop Kconfig GENERIC_VDSO_TIME_NS

2025-09-04T09:23:50+00:00

All architectures implementing time-related functionality in the vDSO are
using the generic vDSO library which handles time namespaces properly.

Remove the now unnecessary Kconfig symbol.

Enables the use of time namespaces on architectures, which use the
generic vDSO but did not enable GENERIC_VDSO_TIME_NS, namely MIPS and arm.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Acked-by: Catalin Marinas 
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-10-d9b65750e49f@linutronix.de

vdso: Drop Kconfig GENERIC_VDSO_DATA_STORE

2025-09-04T09:23:50+00:00

All users of the generic vDSO library also use the generic vDSO datastore.

Remove the now unnecessary Kconfig symbol.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Acked-by: Catalin Marinas 
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-9-d9b65750e49f@linutronix.de

vdso: Drop kconfig GENERIC_COMPAT_VDSO

2025-09-04T09:23:50+00:00

This configuration is never used.

Remove it.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Acked-by: Catalin Marinas 
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-8-d9b65750e49f@linutronix.de

vdso: Drop kconfig GENERIC_VDSO_32

2025-09-04T09:23:50+00:00

This configuration is never used.

Remove it.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-7-d9b65750e49f@linutronix.de

vdso/gettimeofday: Remove !CONFIG_TIME_NS stubs

2025-09-04T09:23:49+00:00

All calls of these functions are already gated behind CONFIG_TIME_NS. The
compiler will already optimize them away if time namespaces are disabled.

Drop the unnecessary stubs.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-4-d9b65750e49f@linutronix.de

vdso/datastore: Gate time data behind CONFIG_GENERIC_GETTIMEOFDAY

2025-09-04T09:23:49+00:00

When the generic vDSO does not provide time functions, as for example on
riscv32, then the time data store is not necessary.

Avoid allocating these time data pages when not used.

Fixes: df7fcbefa710 ("vdso: Add generic time data storage")
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-1-d9b65750e49f@linutronix.de

vdso/gettimeofday: Add support for auxiliary clocks

2025-07-18T12:09:39+00:00

Expose the auxiliary clocks through the vDSO.

Architectures not using the generic vDSO time framework,
namely SPARC64, are not supported.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-12-df7d9f87b9b8@linutronix.de

vdso/gettimeofday: Introduce vdso_get_timestamp()

2025-07-18T11:45:32+00:00

This code is duplicated and with the introduction of auxiliary clocks will
be duplicated even more.

Introduce a helper.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-9-df7d9f87b9b8@linutronix.de