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[Xen-devel] [PATCH 03/14] xen: events: simplify comment

To: xen-devel@xxxxxxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx
Subject: [Xen-devel] [PATCH 03/14] xen: events: simplify comment
From: Ian Campbell <ian.campbell@xxxxxxxxxx>
Date: Wed, 9 Mar 2011 17:41:15 +0000
Cc: Jeremy Fitzhardinge <jeremy@xxxxxxxx>, Stefano Stabellini <Stefano.Stabellini@xxxxxxxxxxxxx>, Ian Campbell <ian.campbell@xxxxxxxxxx>, Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
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It is never valid assume any particular relationship between a Xen
PIRQ number and and Linux IRQ number so there is no need to hedge when
saying so.

Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
 drivers/xen/events.c |   10 +++-------
 include/xen/events.h |    4 +---
 2 files changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 2ce95a6..a9c154d 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -583,13 +583,9 @@ int xen_allocate_pirq(unsigned gsi, int shareable, char 
        return xen_map_pirq_gsi(gsi, gsi, shareable, name);
-/* xen_map_pirq_gsi might allocate irqs from the top down, as a
- * consequence don't assume that the irq number returned has a low value
- * or can be used as a pirq number unless you know otherwise.
- *
- * One notable exception is when xen_map_pirq_gsi is called passing an
- * hardware gsi as argument, in that case the irq number returned
- * matches the gsi number passed as second argument.
+ * Do not make any assumptions regarding the relationship between the
+ * IRQ number returned here and the Xen pirq argument.
  * Note: We don't assign an event channel until the irq actually started
  * up.  Return an existing irq if we've already got one for the gsi.
diff --git a/include/xen/events.h b/include/xen/events.h
index 962da2c..f6fed94 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -68,9 +68,7 @@ int xen_set_callback_via(uint64_t via);
 void xen_evtchn_do_upcall(struct pt_regs *regs);
 void xen_hvm_evtchn_do_upcall(void);
-/* Allocate an irq for a physical interrupt, given a gsi.  "Legacy"
- * GSIs are identity mapped; others are dynamically allocated as
- * usual. */
+/* Allocate an irq for a physical interrupt, given a gsi. */
 int xen_allocate_pirq(unsigned gsi, int shareable, char *name);
 int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name);

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