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17 May 2024, 11:00:25 UTC
Revision 46fe18b16c4656969347fc0a3d83a034e47d9119 authored by Jens Axboe on 04 March 2021, 19:39:36 UTC, committed by Jens Axboe on 05 March 2021, 15:43:01 UTC 
io_uring: move to using create_io_thread()
 
This allows us to do task creation and setup without needing to use
completions to try and synchronize with the starting thread. Get rid of
the old io_wq_fork_thread() wrapper, and the 'wq' and 'worker' startup
completion events - we can now do setup before the task is running.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
1 parent cc440e8
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Tip revision: 46fe18b16c4656969347fc0a3d83a034e47d9119 authored by Jens Axboe on 04 March 2021, 19:39:36 UTC
io_uring: move to using create_io_thread()
Tip revision: 46fe18b
memweight.c 
// SPDX-License-Identifier: GPL-2.0
#include <linux/export.h>
#include <linux/bug.h>
#include <linux/bitmap.h>

/**
 * memweight - count the total number of bits set in memory area
 * @ptr: pointer to the start of the area
 * @bytes: the size of the area
 */
size_t memweight(const void *ptr, size_t bytes)
{
	size_t ret = 0;
	size_t longs;
	const unsigned char *bitmap = ptr;

	for (; bytes > 0 && ((unsigned long)bitmap) % sizeof(long);
			bytes--, bitmap++)
		ret += hweight8(*bitmap);

	longs = bytes / sizeof(long);
	if (longs) {
		BUG_ON(longs >= INT_MAX / BITS_PER_LONG);
		ret += bitmap_weight((unsigned long *)bitmap,
				longs * BITS_PER_LONG);
		bytes -= longs * sizeof(long);
		bitmap += longs * sizeof(long);
	}
	/*
	 * The reason that this last loop is distinct from the preceding
	 * bitmap_weight() call is to compute 1-bits in the last region smaller
	 * than sizeof(long) properly on big-endian systems.
	 */
	for (; bytes > 0; bytes--, bitmap++)
		ret += hweight8(*bitmap);

	return ret;
}
EXPORT_SYMBOL(memweight);
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