Commit eda86a41 authored by Shrikanth Hegde's avatar Shrikanth Hegde Committed by Madhavan Srinivasan
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powerpc: Large user copy aware of full:rt:lazy preemption 



Large user copy_to/from (more than 16 bytes) uses vmx instructions to
speed things up. Once the copy is done, it makes sense to try schedule
as soon as possible for preemptible kernels. So do this for
preempt=full/lazy and rt kernel.

Not checking for lazy bit here, since it could lead to unnecessary
context switches.

Suggested-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarShrikanth Hegde <sshegde@linux.ibm.com>
Signed-off-by: default avatarMadhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20241116192306.88217-3-sshegde@linux.ibm.com
parent 00199ed6

arch/powerpc/lib/vmx-helper.c

+1 −1
Original line number Diff line number Diff line
@@ -45,7 +45,7 @@ int exit_vmx_usercopy(void) 
	 * set and we are preemptible. The hack here is to schedule a

	 * decrementer to fire here and reschedule for us if necessary.

	 */

	if (IS_ENABLED(CONFIG_PREEMPT) && need_resched())

	if (IS_ENABLED(CONFIG_PREEMPTION) && need_resched())

		set_dec(1);

	return 0;

}