linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Alexander Gordeev <agordeev@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: x86@kernel.org, linux-pci@vger.kernel.org,
	linux-ide@vger.kernel.org, Tejun Heo <tj@kernel.org>,
	Ingo Molnar <mingo@kernel.org>, Joerg Roedel <joro@8bytes.org>,
	Jan Beulich <JBeulich@suse.com>,
	Bjorn Helgaas <bhelgaas@google.com>
Subject: [PATCH v2 4/6] AHCI: Conserve interrupts with pci_enable_msi_block_part() interface
Date: Thu, 5 Sep 2013 14:53:47 +0200	[thread overview]
Message-ID: <cb77da9322a63c609dc5aa49aa57c9706bf37a24.1378383792.git.agordeev@redhat.com> (raw)
In-Reply-To: <cover.1378383792.git.agordeev@redhat.com>

Make use of the new pci_enable_msi_block_part() interface
and conserve on othewise wasted interrupt resources for 10
of 16 unused MSI vectors on Intel chipsets.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
---
 drivers/ata/ahci.c |   46 +++++++++++++++++++++++++++-------------------
 1 files changed, 27 insertions(+), 19 deletions(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index db4380d..a6bb618 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1091,26 +1091,34 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host)
 {}
 #endif
 
-int ahci_init_interrupts(struct pci_dev *pdev, struct ahci_host_priv *hpriv)
+int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
+			 struct ahci_host_priv *hpriv)
 {
 	int rc;
 	unsigned int maxvec;
 
-	if (!(hpriv->flags & AHCI_HFLAG_NO_MSI)) {
-		rc = pci_enable_msi_block_auto(pdev, &maxvec);
-		if (rc > 0) {
-			if ((rc == maxvec) || (rc == 1))
-				return rc;
-			/*
-			 * Assume that advantage of multipe MSIs is negated,
-			 * so fallback to single MSI mode to save resources
-			 */
-			pci_disable_msi(pdev);
-			if (!pci_enable_msi(pdev))
-				return 1;
-		}
-	}
+	if (hpriv->flags & AHCI_HFLAG_NO_MSI)
+		goto intx;
+
+	maxvec = pci_get_msi_cap(pdev);
+	if (maxvec < 0)
+		goto intx;
+	if (maxvec < n_ports)
+		goto single_msi;
+
+	rc = pci_enable_msi_block_part(pdev, n_ports, maxvec);
+	if (rc < 0)
+		goto intx;
+	if (rc)
+		goto single_msi;
+
+	return maxvec;
 
+single_msi:
+	if (!pci_enable_msi(pdev))
+		return 1;
+
+intx:
 	pci_intx(pdev, 1);
 	return 0;
 }
@@ -1277,10 +1285,6 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	hpriv->mmio = pcim_iomap_table(pdev)[ahci_pci_bar];
 
-	n_msis = ahci_init_interrupts(pdev, hpriv);
-	if (n_msis > 1)
-		hpriv->flags |= AHCI_HFLAG_MULTI_MSI;
-
 	/* save initial config */
 	ahci_pci_save_initial_config(pdev, hpriv);
 
@@ -1327,6 +1331,10 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	 */
 	n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
 
+	n_msis = ahci_init_interrupts(pdev, n_ports, hpriv);
+	if (n_msis > 1)
+		hpriv->flags |= AHCI_HFLAG_MULTI_MSI;
+
 	host = ata_host_alloc_pinfo(&pdev->dev, ppi, n_ports);
 	if (!host)
 		return -ENOMEM;
-- 
1.7.7.6


-- 
Regards,
Alexander Gordeev
agordeev@redhat.com

  parent reply	other threads:[~2013-09-05 12:53 UTC|newest]

Thread overview: 73+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-05 12:51 [PATCH v2 0/6] AHCI: Conserve interrupts with pci_enable_msi_block_part() interface Alexander Gordeev
2013-09-05 12:52 ` [PATCH v2 1/6] PCI/MSI: Introduce " Alexander Gordeev
2013-09-05 12:52 ` [PATCH v2 2/6] PCI/MSI: Factor out pci_get_msi_cap() interface Alexander Gordeev
2013-09-05 13:09   ` Tejun Heo
2013-09-05 15:03     ` Alexander Gordeev
2013-09-05 15:04       ` Tejun Heo
2013-09-05 15:40         ` Alexander Gordeev
2013-09-05 15:44           ` Tejun Heo
2013-09-05 18:54             ` Alexander Gordeev
2013-09-05 20:06               ` Tejun Heo
2013-09-06 16:01                 ` Bjorn Helgaas
2013-09-06 16:06                   ` Tejun Heo
2013-09-06 23:32                     ` Bjorn Helgaas
2013-09-09 15:20                       ` Alexander Gordeev
2013-09-09 15:22                         ` [PATCH 1/9] PCI/MSI/PPC: Fix wrong RTAS error code reporting Alexander Gordeev
2013-09-09 15:22                         ` [PATCH 2/9] PCI/MSI/PPC: Make return values only 0/-errno when MSIs allocated Alexander Gordeev
2013-09-09 15:24                         ` [PATCH 3/9] PCI/MSI/x86: " Alexander Gordeev
2013-09-09 15:24                         ` [PATCH 4/9] PCI/MSI/MIPS: " Alexander Gordeev
2013-09-09 15:25                         ` [PATCH 2/9] PCI/MSI/PPC: Make return values only 0/-errno when MSIs allocated[PATCH 5/9] PCI/MSI/s390: " Alexander Gordeev
2013-09-09 15:38                           ` scrap this one Alexander Gordeev
2013-09-09 15:26                         ` [PATCH 5/9] PCI/MSI/s390: Make return values only 0/-errno when MSIs allocated Alexander Gordeev
2013-09-10 12:42                           ` Sergei Shtylyov
2013-09-10 13:09                             ` Alexander Gordeev
2013-09-09 15:27                         ` [PATCH 6/9] PCI/MSI/s390: Remove superfluous check of MSI type Alexander Gordeev
2013-09-09 15:28                         ` [PATCH 7/9] PCI/MSI/s390: Make return values only 0/-errno when MSIs allocated Alexander Gordeev
2013-09-09 15:29                         ` [PATCH 8/9] PCI/MSI: Fix return value when populate_msi_sysfs() failed Alexander Gordeev
2013-09-09 15:29                         ` [PATCH 9/9] PCI/MSI: Make return values only 0/-errno when MSIs allocated Alexander Gordeev
2013-09-09 15:37                         ` [PATCH v2 2/6] PCI/MSI: Factor out pci_get_msi_cap() interface Tejun Heo
2013-09-09 15:45                           ` Alexander Gordeev
2013-09-16 10:22                         ` Alexander Gordeev
2013-09-17 14:30                           ` Michael Ellerman
2013-09-18  9:48                             ` Alexander Gordeev
2013-09-18 14:22                               ` Tejun Heo
2013-09-18 16:50                                 ` Alexander Gordeev
2013-09-20  8:24                                   ` Alexander Gordeev
2013-09-20 12:27                                     ` Tejun Heo
2013-09-25 18:02                                       ` Bjorn Helgaas
2013-09-25 20:58                                         ` Alexander Gordeev
2013-09-25 21:00                                           ` Tejun Heo
2013-09-26  7:46                                             ` Alexander Gordeev
2013-09-26  8:58                                               ` David Laight
2013-09-26 10:45                                                 ` Alexander Gordeev
2013-09-26 11:34                                                   ` David Laight
2013-09-26 12:13                                                     ` Alexander Gordeev
2013-09-26 13:11                                               ` Tejun Heo
2013-09-26 14:39                                                 ` Alexander Gordeev
2013-09-26 14:42                                                   ` Tejun Heo
2013-10-01  7:19                                                   ` Michael Ellerman
2013-09-20 12:26                                   ` Tejun Heo
2013-10-01  7:26                                     ` Michael Ellerman
2013-10-01  7:35                                 ` Michael Ellerman
2013-10-01 11:55                                   ` Tejun Heo
2013-10-02  2:33                                     ` Michael Ellerman
2013-10-02  3:23                                       ` Tejun Heo
2013-09-26 12:32                               ` Mark Lord
2013-09-26 13:03                                 ` Alexander Gordeev
2013-10-02  2:46                                   ` Mark Lord
2013-10-02  7:26                                     ` Alexander Gordeev
2013-12-18 18:26                                 ` Bjorn Helgaas
2013-10-01  7:51                               ` Michael Ellerman
2013-10-01 10:35                                 ` Alexander Gordeev
2013-10-02  2:43                                   ` Michael Ellerman
2013-10-02  7:10                                     ` Alexander Gordeev
2013-09-06 13:17           ` Alexander Gordeev
2013-09-05 12:53 ` [PATCH v2 3/6] MSI/x86: Support pci_enable_msi_block_part() interface Alexander Gordeev
2013-09-05 12:53 ` Alexander Gordeev [this message]
2013-09-05 13:10   ` [PATCH v2 4/6] AHCI: Conserve interrupts with " Tejun Heo
2013-09-05 15:23     ` Alexander Gordeev
2013-09-05 12:54 ` [PATCH v2 5/6] AHCI: Check MRSM bit when multiple MSIs enabled Alexander Gordeev
2013-09-05 13:11   ` Tejun Heo
2013-09-05 15:25     ` Alexander Gordeev
2013-09-05 14:32   ` Sergei Shtylyov
2013-09-05 12:54 ` [PATCH v2 6/6] PCI/MSI: Get rid of pci_enable_msi_block_auto() interface Alexander Gordeev

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=cb77da9322a63c609dc5aa49aa57c9706bf37a24.1378383792.git.agordeev@redhat.com \
    --to=agordeev@redhat.com \
    --cc=JBeulich@suse.com \
    --cc=bhelgaas@google.com \
    --cc=joro@8bytes.org \
    --cc=linux-ide@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=tj@kernel.org \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).