Unverified Commit 784e48a8 authored by Jake Hillion's avatar Jake Hillion Committed by Ilpo Järvinen
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x86/platform/amd: replace down_timeout() with down_interruptible() 



Currently hsmp_send_message() uses down_timeout() with a 100ms timeout
to take the semaphore. However __hsmp_send_message(), the content of the
critical section, has a sleep in it. On systems with significantly
delayed scheduling behaviour this may take over 100ms.

Convert this method to down_interruptible(). Leave the error handling
the same as the documentation currently is not specific about what error
is returned.

Previous behaviour: a caller who competes with another caller stuck in
the critical section due to scheduler delays would receive -ETIME.

New behaviour: a caller who competes with another caller stuck in the
critical section due to scheduler delays will complete successfully.

Reviewed-by: default avatarSuma Hegde <suma.hegde@amd.com>
Tested-by: default avatarSuma Hegde <suma.hegde@amd.com>
Signed-off-by: default avatarJake Hillion <jake@hillion.co.uk>
Link: https://lore.kernel.org/r/20250605-amd-hsmp-v2-2-a811bc3dd74a@hillion.co.uk


Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
parent f8afb12a

drivers/platform/x86/amd/hsmp/hsmp.c

+1 −7
Original line number Diff line number Diff line
@@ -214,13 +214,7 @@ int hsmp_send_message(struct hsmp_message *msg) 
		return -ENODEV;

	sock = &hsmp_pdev.sock[msg->sock_ind];



	/*

	 * The time taken by smu operation to complete is between

	 * 10us to 1ms. Sometime it may take more time.

	 * In SMP system timeout of 100 millisecs should

	 * be enough for the previous thread to finish the operation

	 */

	ret = down_timeout(&sock->hsmp_sem, msecs_to_jiffies(HSMP_MSG_TIMEOUT));

	ret = down_interruptible(&sock->hsmp_sem);

	if (ret < 0)

		return ret;