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Subject[PATCH 08/11] staging: gasket: page_table: simplify gasket_components_to_dev_address
Date
From: Nick Ewalt <nicholasewalt@google.com>

Refactor gasket_components_to_dev_address to be faster and easier to
understand. The old implementation was unnecessarily complex and masked
the page_index for simple addresses but not extended ones. It makes the
most sense for this function to perform no such masking.

Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
---
drivers/staging/gasket/gasket_page_table.c | 21 ++-------------------
1 file changed, 2 insertions(+), 19 deletions(-)

diff --git a/drivers/staging/gasket/gasket_page_table.c b/drivers/staging/gasket/gasket_page_table.c
index ec9359576ea7c..c2fbab74194f8 100644
--- a/drivers/staging/gasket/gasket_page_table.c
+++ b/drivers/staging/gasket/gasket_page_table.c
@@ -699,26 +699,9 @@ static ulong gasket_components_to_dev_address(struct gasket_page_table *pg_tbl,
int is_simple, uint page_index,
uint offset)
{
- ulong lvl0_index, lvl1_index;
+ ulong dev_addr = (page_index << GASKET_SIMPLE_PAGE_SHIFT) | offset;

- if (is_simple) {
- /* Return simple addresses directly. */
- lvl0_index = page_index & (pg_tbl->config.total_entries - 1);
- return (lvl0_index << GASKET_SIMPLE_PAGE_SHIFT) | offset;
- }
-
- /*
- * This could be compressed into fewer statements, but
- * A) the compiler should optimize it
- * B) this is not slow
- * C) this is an uncommon operation
- * D) this is actually readable this way.
- */
- lvl0_index = page_index / GASKET_PAGES_PER_SUBTABLE;
- lvl1_index = page_index & (GASKET_PAGES_PER_SUBTABLE - 1);
- return (pg_tbl)->extended_flag |
- (lvl0_index << GASKET_EXTENDED_LVL0_SHIFT) |
- (lvl1_index << GASKET_EXTENDED_LVL1_SHIFT) | offset;
+ return is_simple ? dev_addr : (pg_tbl->extended_flag | dev_addr);
}

/*
--
2.19.0.605.g01d371f741-goog
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