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From: Tiwei Bie <tiwei.bie@linux.dev>
To: richard@nod.at, anton.ivanov@cambridgegreys.com,
	johannes@sipsolutions.net
Cc: linux-um@lists.infradead.org, linux-kernel@vger.kernel.org,
	benjamin@sipsolutions.net, arnd@arndb.de, tiwei.btw@antgroup.com,
	tiwei.bie@linux.dev, Johannes Berg <johannes.berg@intel.com>
Subject: [PATCH v4 6/8] um: vdso: Remove getcpu support on x86
Date: Mon, 27 Oct 2025 08:18:13 +0800	[thread overview]
Message-ID: <20251027001815.1666872-7-tiwei.bie@linux.dev> (raw)
In-Reply-To: <20251027001815.1666872-1-tiwei.bie@linux.dev>

From: Tiwei Bie <tiwei.btw@antgroup.com>

We are going to support SMP on UML/x86, so we can't hard code
the CPU and NUMA node in __vdso_getcpu() anymore. Let's just
remove it and let applications fall back to the syscall.

Suggested-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
---
 arch/x86/um/vdso/um_vdso.c  | 20 --------------------
 arch/x86/um/vdso/vdso.lds.S |  2 --
 2 files changed, 22 deletions(-)

diff --git a/arch/x86/um/vdso/um_vdso.c b/arch/x86/um/vdso/um_vdso.c
index cbae2584124f..43a5ffcc7158 100644
--- a/arch/x86/um/vdso/um_vdso.c
+++ b/arch/x86/um/vdso/um_vdso.c
@@ -10,14 +10,12 @@
 #define DISABLE_BRANCH_PROFILING
 
 #include <linux/time.h>
-#include <linux/getcpu.h>
 #include <asm/unistd.h>
 
 /* workaround for -Wmissing-prototypes warnings */
 int __vdso_clock_gettime(clockid_t clock, struct __kernel_old_timespec *ts);
 int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz);
 __kernel_old_time_t __vdso_time(__kernel_old_time_t *t);
-long __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused);
 
 int __vdso_clock_gettime(clockid_t clock, struct __kernel_old_timespec *ts)
 {
@@ -58,21 +56,3 @@ __kernel_old_time_t __vdso_time(__kernel_old_time_t *t)
 	return secs;
 }
 __kernel_old_time_t time(__kernel_old_time_t *t) __attribute__((weak, alias("__vdso_time")));
-
-long
-__vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused)
-{
-	/*
-	 * UML does not support SMP, we can cheat here. :)
-	 */
-
-	if (cpu)
-		*cpu = 0;
-	if (node)
-		*node = 0;
-
-	return 0;
-}
-
-long getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *tcache)
-	__attribute__((weak, alias("__vdso_getcpu")));
diff --git a/arch/x86/um/vdso/vdso.lds.S b/arch/x86/um/vdso/vdso.lds.S
index 73c508587a98..401600effc0a 100644
--- a/arch/x86/um/vdso/vdso.lds.S
+++ b/arch/x86/um/vdso/vdso.lds.S
@@ -22,8 +22,6 @@ VERSION {
 		__vdso_clock_gettime;
 		gettimeofday;
 		__vdso_gettimeofday;
-		getcpu;
-		__vdso_getcpu;
 		time;
 		__vdso_time;
 	local: *;
-- 
2.34.1



  parent reply	other threads:[~2025-10-27  0:18 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-27  0:18 [PATCH v4 0/8] um: Add SMP support Tiwei Bie
2025-10-27  0:18 ` [PATCH v4 1/8] um: Do not disable kmalloc in initial_thread_cb() Tiwei Bie
2025-10-27  0:18 ` [PATCH v4 2/8] um: Turn signals_* into thread-local variables Tiwei Bie
2025-10-27  0:18 ` [PATCH v4 3/8] um: Determine sleep based on need_resched() Tiwei Bie
2025-10-27  0:18 ` [PATCH v4 4/8] um: Define timers on a per-CPU basis Tiwei Bie
2025-10-27  0:18 ` [PATCH v4 5/8] um: Add initial SMP support Tiwei Bie
2025-10-27  0:18 ` Tiwei Bie [this message]
2025-10-27  0:18 ` [PATCH v4 7/8] asm-generic: percpu: Add assembly guard Tiwei Bie
2025-10-27  0:18 ` [PATCH v4 8/8] um: Enable SMP support on x86 Tiwei Bie

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