#include "cache.h"
#include "config.h"
#include <stdio.h>
#include <subcmd/help.h>
#include "../builtin.h"
#include "levenshtein.h"

static int autocorrect;
static struct cmdnames aliases;

static int perf_unknown_cmd_config(const char *var, const char *value,
				   void *cb __maybe_unused)
{
	if (!strcmp(var, "help.autocorrect"))
		autocorrect = perf_config_int(var,value);
	/* Also use aliases for command lookup */
	if (!prefixcmp(var, "alias."))
		add_cmdname(&aliases, var + 6, strlen(var + 6));

	return 0;
}

static int levenshtein_compare(const void *p1, const void *p2)
{
	const struct cmdname *const *c1 = p1, *const *c2 = p2;
	const char *s1 = (*c1)->name, *s2 = (*c2)->name;
	int l1 = (*c1)->len;
	int l2 = (*c2)->len;
	return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
}

static int add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
{
	unsigned int i, nr = cmds->cnt + old->cnt;
	void *tmp;

	if (nr > cmds->alloc) {
		/* Choose bigger one to alloc */
		if (alloc_nr(cmds->alloc) < nr)
			cmds->alloc = nr;
		else
			cmds->alloc = alloc_nr(cmds->alloc);
		tmp = realloc(cmds->names, cmds->alloc * sizeof(*cmds->names));
		if (!tmp)
			return -1;
		cmds->names = tmp;
	}
	for (i = 0; i < old->cnt; i++)
		cmds->names[cmds->cnt++] = old->names[i];
	zfree(&old->names);
	old->cnt = 0;
	return 0;
}

const char *help_unknown_cmd(const char *cmd)
{
	unsigned int i, n = 0, best_similarity = 0;
	struct cmdnames main_cmds, other_cmds;

	memset(&main_cmds, 0, sizeof(main_cmds));
	memset(&other_cmds, 0, sizeof(main_cmds));
	memset(&aliases, 0, sizeof(aliases));

	perf_config(perf_unknown_cmd_config, NULL);

	load_command_list("perf-", &main_cmds, &other_cmds);

	if (add_cmd_list(&main_cmds, &aliases) < 0 ||
	    add_cmd_list(&main_cmds, &other_cmds) < 0) {
		fprintf(stderr, "ERROR: Failed to allocate command list for unknown command.\n");
		goto end;
	}
	qsort(main_cmds.names, main_cmds.cnt,
	      sizeof(main_cmds.names), cmdname_compare);
	uniq(&main_cmds);

	if (main_cmds.cnt) {
		/* This reuses cmdname->len for similarity index */
		for (i = 0; i < main_cmds.cnt; ++i)
			main_cmds.names[i]->len =
				levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4);

		qsort(main_cmds.names, main_cmds.cnt,
		      sizeof(*main_cmds.names), levenshtein_compare);

		best_similarity = main_cmds.names[0]->len;
		n = 1;
		while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len)
			++n;
	}

	if (autocorrect && n == 1) {
		const char *assumed = main_cmds.names[0]->name;

		main_cmds.names[0] = NULL;
		clean_cmdnames(&main_cmds);
		fprintf(stderr, "WARNING: You called a perf program named '%s', "
			"which does not exist.\n"
			"Continuing under the assumption that you meant '%s'\n",
			cmd, assumed);
		if (autocorrect > 0) {
			fprintf(stderr, "in %0.1f seconds automatically...\n",
				(float)autocorrect/10.0);
			poll(NULL, 0, autocorrect * 100);
		}
		return assumed;
	}

	fprintf(stderr, "perf: '%s' is not a perf-command. See 'perf --help'.\n", cmd);

	if (main_cmds.cnt && best_similarity < 6) {
		fprintf(stderr, "\nDid you mean %s?\n",
			n < 2 ? "this": "one of these");

		for (i = 0; i < n; i++)
			fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
	}
end:
	exit(1);
}
1fda2d530d3b268eef542c5414e54bf1a'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Iago Abal &lt;mail@iagoabal.eu&gt;</td><td class='right'>2017-01-11 14:00:21 +0100</td></tr>
<tr><th>committer</th><td>Vinod Koul &lt;vinod.koul@intel.com&gt;</td><td class='right'>2017-01-25 15:35:11 +0530</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/ipv4/tcp_metrics.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>91539eb1fda2d530d3b268eef542c5414e54bf1a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/ipv4/tcp_metrics.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>960f5ca6342ad20837aff18aad6e8ecd7da32fd6</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/ipv4/tcp_metrics.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>net/ipv4/tcp_metrics.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/ipv4/tcp_metrics.c?id=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>6610d0edf6dc7ee97e46ab3a538a565c79d26199</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/ipv4/tcp_metrics.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a&amp;id2=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>diff</a>)</td></tr></table>
<div class='commit-subject'>dmaengine: pl330: fix double lock</div><div class='commit-msg'>The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the
following double-lock bug:

    Double lock:
    1. spin_lock_irqsave(pch-&gt;lock, flags) at pl330_free_chan_resources:2236;
    2. call to function `pl330_release_channel' immediately after;
    3. call to function `dma_pl330_rqcb' in line 1753;
    4. spin_lock_irqsave(pch-&gt;lock, flags) at dma_pl330_rqcb:1505.

I have fixed it as suggested by Marek Szyprowski.

First, I have replaced `pch-&gt;lock' with `pl330-&gt;lock' in functions
`pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids
the double-lock by acquiring a different lock than `dma_pl330_rqcb'.

NOTE that, as a result, `pl330_free_chan_resources' executes
`list_splice_tail_init' on `pch-&gt;work_list' under lock `pl330-&gt;lock',
whereas in the rest of the code `pch-&gt;work_list' is protected by
`pch-&gt;lock'. I don't know if this may cause race conditions. Similarly
`pch-&gt;cyclic' is written by `pl330_alloc_chan_resources' under
`pl330-&gt;lock' but read by `pl330_tx_submit' under `pch-&gt;lock'.

Second, I have removed locking from `pl330_request_channel' and
`pl330_release_channel' functions. Function `pl330_request_channel' is
only called from `pl330_alloc_chan_resources', so the lock is already
held. Function `pl330_release_channel' is called from
`pl330_free_chan_resources', which already holds the lock, and from
`pl330_del'. Function `pl330_del' is called in an error path of
`pl330_probe' and at the end of `pl330_remove', but I assume that there
cannot be concurrent accesses to the protected data at those points.

Signed-off-by: Iago Abal &lt;mail@iagoabal.eu&gt;
Reviewed-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Vinod Koul &lt;vinod.koul@intel.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>Diffstat</a> (limited to 'net/ipv4/tcp_metrics.c')</div><table summary='diffstat' class='diffstat'>