From patchwork Thu Dec 19 21:49:28 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Randy Dunlap X-Patchwork-Id: 852292 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A065B8F6D; Thu, 19 Dec 2024 21:49:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734644977; cv=none; b=LRr7SFDlVdcnBA6J/5zqDGWkf1mOQFlwbZPoVOixhOhb+jDe6g3T6TQmviGrHIzrN4kFz+l+cUxqNsswQXFm2hZC6uk4xdxHTc73ZV+INK722ogWHINYzUW8PpkZOPVHA5NE/n7bdV0cSBJIZjDKLK7LzYNd7hQF47q7pwoTBUw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734644977; c=relaxed/simple; bh=pOuqnKIFfDOuJbt8wzSYVnYP0AGZfUm7m4WIaN0n8GM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Bc50NfXO/+PQqDIWRgJHkV3XpeBYG4fy4MuOza4S5XlOJh+EQm9R7kCfEOfP+TLb/UjiAfNOdgao9/5yuosqGXC/GuG2oSH1+clqZeI7G2iHuAMS+T56mnWsAySs39qr6ePvFlQnEYfj+fhnWu00Rumu0QIG0PCo7HKz653i2NU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=NQftOciz; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="NQftOciz" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:In-Reply-To:References; bh=CG+y38/wd3+mfeCBhwqUa50I/70VetXzAPAvCxo6yCE=; b=NQftOcizPZ3VUp9U52EOFBKitV W+MTH/frVXHRDADQuz48UipKW2mJSpqkRNSPcCBW4bZPnZjXC+88v7hLhz195IgKwFkkEB7YzrFGo 77uQPGrZPQtxeT09ZVrYpKk810Wdegq2ks00OKNeAkYLN6f/SYDVKQZvaz4oGkmeYSjumNkGkw6yj KxgkvYrQmrIFkAK17SUlhNTTUIXwCfMe635Tjx31os7QribmqTxCCxxSYzt7nDQSwpT1Ejmc6NtP9 b3ge6qplxkZbaIrItIahU/MxhgJqiZL1sE3udLy8aO/RMj+q5s7CwtV23iRsZb8Oux1u/dLdWCgC2 t+tDczHw==; Received: from [50.53.2.24] (helo=bombadil.infradead.org) by bombadil.infradead.org with esmtpsa (Exim 4.98 #2 (Red Hat Linux)) id 1tOOOi-00000003CZ4-2CAl; Thu, 19 Dec 2024 21:49:32 +0000 From: Randy Dunlap To: linux-scsi@vger.kernel.org Cc: Randy Dunlap , Jonathan Corbet , linux-doc@vger.kernel.org, "James E.J. Bottomley" , "Martin K. Petersen" Subject: [PATCH] scsi: documentation: scsi_eh: updates for EH changes Date: Thu, 19 Dec 2024 13:49:28 -0800 Message-ID: <20241219214928.1170302-1-rdunlap@infradead.org> X-Mailer: git-send-email 2.47.1 Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 SCSI_SOFTIRQ and scsi_softirq() are no longer used. Change to block layer equivalents. scsi_setup_cmd_retry() has been deleted. Remove references to it. SCSI_EH_CANCEL_CMD has been deleted. Remove references to it. scsi_eh_abort_cmds() has been deleted. Remove references to it. START_STOP_UNIT command should be "START_STOP" instead. Signed-off-by: Randy Dunlap Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org Cc: "James E.J. Bottomley" Cc: "Martin K. Petersen" --- Documentation/scsi/scsi_eh.rst | 46 ++++++------------------------- 1 file changed, 9 insertions(+), 37 deletions(-) --- linux-next-20241218.orig/Documentation/scsi/scsi_eh.rst +++ linux-next-20241218/Documentation/scsi/scsi_eh.rst @@ -54,13 +54,13 @@ invoking hostt->queuecommand() or the bl ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ For all non-EH commands, scsi_done() is the completion callback. It -just calls blk_complete_request() to delete the block layer timer and -raise SCSI_SOFTIRQ +just calls blk_mq_complete_request() to delete the block layer timer and +raise BLOCK_SOFTIRQ. -SCSI_SOFTIRQ handler scsi_softirq calls scsi_decide_disposition() to -determine what to do with the command. scsi_decide_disposition() -looks at the scmd->result value and sense data to determine what to do -with the command. +The BLOCK_SOFTIRQ indirectly calls scsi_complete(), which calls +scsi_decide_disposition() to determine what to do with the command. +scsi_decide_disposition() looks at the scmd->result value and sense +data to determine what to do with the command. - SUCCESS @@ -110,7 +110,7 @@ The timeout handler is scsi_timeout(). retry which failed), when retries are exceeded, or when the EH deadline is expired. In these cases Step #3 is taken. - 3. scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD) is invoked for the + 3. scsi_eh_scmd_add(scmd) is invoked for the command. See [1-4] for more information. 1.3 Asynchronous command aborts @@ -277,7 +277,6 @@ scmd->allowed. :ACTION: scsi_eh_finish_cmd() is invoked to EH-finish scmd - - scsi_setup_cmd_retry() - move from local eh_work_q to local eh_done_q :LOCKING: none @@ -317,7 +316,7 @@ scmd->allowed. ``scsi_eh_get_sense`` This action is taken for each error-completed - (!SCSI_EH_CANCEL_CMD) commands without valid sense data. Most + command without valid sense data. Most SCSI transports/LLDDs automatically acquire sense data on command failures (autosense). Autosense is recommended for performance reasons and as sense information could get out of @@ -347,30 +346,6 @@ scmd->allowed. - otherwise No action. - 3. If !list_empty(&eh_work_q), invoke scsi_eh_abort_cmds(). - - ``scsi_eh_abort_cmds`` - - This action is taken for each timed out command when - no_async_abort is enabled in the host template. - hostt->eh_abort_handler() is invoked for each scmd. The - handler returns SUCCESS if it has succeeded to make LLDD and - all related hardware forget about the scmd. - - If a timedout scmd is successfully aborted and the sdev is - either offline or ready, scsi_eh_finish_cmd() is invoked for - the scmd. Otherwise, the scmd is left in eh_work_q for - higher-severity actions. - - Note that both offline and ready status mean that the sdev is - ready to process new scmds, where processing also implies - immediate failing; thus, if a sdev is in one of the two - states, no further recovery action is needed. - - Device readiness is tested using scsi_eh_tur() which issues - TEST_UNIT_READY command. Note that the scmd must have been - aborted successfully before reusing it for TEST_UNIT_READY. - 4. If !list_empty(&eh_work_q), invoke scsi_eh_ready_devs() ``scsi_eh_ready_devs`` @@ -384,7 +359,7 @@ scmd->allowed. For each sdev which has failed scmds with valid sense data of which scsi_check_sense()'s verdict is FAILED, - START_STOP_UNIT command is issued w/ start=1. Note that + START_STOP command is issued w/ start=1. Note that as we explicitly choose error-completed scmds, it is known that lower layers have forgotten about the scmd and we can reuse it for STU. @@ -478,9 +453,6 @@ except for #1 must be implemented by eh_ - shost->host_failed is zero. - - Each scmd is in such a state that scsi_setup_cmd_retry() on the - scmd doesn't make any difference. - - shost->eh_cmd_q is cleared. - Each scmd->eh_entry is cleared.