LinuxPPC-Dev Archive on lore.kernel.org
 help / color / Atom feed
From: Hari Bathini <hbathini@linux.ibm.com>
To: linuxppc-dev <linuxppc-dev@ozlabs.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.ibm.com>,
	Mahesh J Salgaonkar <mahesh@linux.ibm.com>,
	Vasant Hegde <hegdevasant@linux.ibm.com>,
	Oliver <oohall@gmail.com>, Nicholas Piggin <npiggin@gmail.com>,
	Daniel Axtens <dja@axtens.net>
Subject: [PATCH v5 23/31] powerpc/fadump: consider reserved ranges while releasing memory
Date: Tue, 20 Aug 2019 17:36:57 +0530
Message-ID: <156630281761.8896.4115696964125836702.stgit@hbathini.in.ibm.com> (raw)
In-Reply-To: <156630261682.8896.3418665808003586786.stgit@hbathini.in.ibm.com>

Commit 0962e8004e97 ("powerpc/prom: Scan reserved-ranges node for
memory reservations") enabled support to parse 'reserved-ranges' DT
node to reserve kernel memory falling in these ranges for firmware
purposes. Along with the preserved area memory, ensure memory in
reserved ranges is not overlapped with memory released by capture
kernel aftering saving vmcore. Also, fix the off-by-one error in
fadump_release_reserved_area function while releasing memory.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
 arch/powerpc/kernel/fadump.c |  150 +++++++++++++++++++++++++++++++++++++++---
 1 file changed, 138 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 2dd4621..3981599 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -37,6 +37,7 @@ static struct fw_dump fw_dump;
 
 static DEFINE_MUTEX(fadump_mutex);
 struct fadump_mrange_info crash_mrange_info = { "crash", NULL, 0, 0, 0 };
+struct fadump_mrange_info reserved_mrange_info = { "reserved", NULL, 0, 0, 0 };
 
 #ifdef CONFIG_CMA
 static struct cma *fadump_cma;
@@ -881,33 +882,158 @@ static void fadump_release_reserved_area(unsigned long start, unsigned long end)
 			if (tend == end_pfn)
 				break;
 
-			start_pfn = tend + 1;
+			start_pfn = tend;
 		}
 	}
 }
 
 /*
- * Release the memory that was reserved in early boot to preserve the memory
- * contents. The released memory will be available for general use.
+ * Sort the mem ranges in-place and merge adjacent ranges
+ * to minimize the memory ranges count.
+ */
+static void sort_and_merge_mem_ranges(struct fadump_mrange_info *mrange_info)
+{
+	unsigned long long base, size;
+	struct fadump_memory_range tmp_range;
+	struct fadump_memory_range *mem_ranges;
+	int i, j, idx;
+
+	if (!reserved_mrange_info.mem_range_cnt)
+		return;
+
+	/* Sort the memory ranges */
+	mem_ranges = mrange_info->mem_ranges;
+	for (i = 0; i < mrange_info->mem_range_cnt; i++) {
+		idx = i;
+		for (j = i + 1; j < mrange_info->mem_range_cnt; j++) {
+			if (mem_ranges[idx].base > mem_ranges[j].base)
+				idx = j;
+		}
+		if (idx != i) {
+			tmp_range = mem_ranges[idx];
+			mem_ranges[idx] = mem_ranges[i];
+			mem_ranges[i] = tmp_range;
+		}
+	}
+
+	/* Merge adjacent reserved ranges */
+	idx = 0;
+	for (i = 1; i < mrange_info->mem_range_cnt; i++) {
+		base = mem_ranges[i-1].base;
+		size = mem_ranges[i-1].size;
+		if (mem_ranges[i].base == (base + size))
+			mem_ranges[idx].size += mem_ranges[i].size;
+		else {
+			idx++;
+			if (i == idx)
+				continue;
+
+			mem_ranges[idx] = mem_ranges[i];
+		}
+	}
+	mrange_info->mem_range_cnt = idx + 1;
+}
+
+/*
+ * Scan reserved-ranges to consider them while reserving/releasing
+ * memory for FADump.
+ */
+static inline int fadump_scan_reserved_mem_ranges(void)
+{
+	int len, ret = -1;
+	unsigned long i;
+	const __be32 *prop;
+	struct device_node *root;
+
+	root = of_find_node_by_path("/");
+	if (!root)
+		return ret;
+
+	prop = of_get_property(root, "reserved-ranges", &len);
+	if (!prop)
+		return ret;
+
+	/*
+	 * Each reserved range is an (address,size) pair, 2 cells each,
+	 * totalling 4 cells per range.
+	 */
+	for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
+		u64 base, size;
+
+		base = of_read_number(prop + (i * 4) + 0, 2);
+		size = of_read_number(prop + (i * 4) + 2, 2);
+
+		if (size) {
+			ret = fadump_add_mem_range(&reserved_mrange_info,
+						   base, base + size);
+			if (ret < 0) {
+				pr_warn("some reserved ranges are ignored!\n");
+				break;
+			}
+		}
+	}
+
+	return ret;
+}
+
+/*
+ * Release the memory that was reserved during early boot to preserve the
+ * crash'ed kernel's memory contents except reserved dump area (permanent
+ * reservation) and reserved ranges used by F/W. The released memory will
+ * be available for general use.
  */
 static void fadump_release_memory(unsigned long begin, unsigned long end)
 {
+	int i, ret;
 	unsigned long ra_start, ra_end;
+	unsigned long tstart;
+
+	fadump_scan_reserved_mem_ranges();
 
 	ra_start = fw_dump.reserve_dump_area_start;
 	ra_end = ra_start + fw_dump.reserve_dump_area_size;
 
 	/*
-	 * exclude the dump reserve area. Will reuse it for next
-	 * fadump registration.
+	 * Add reserved dump area to reserved ranges list
+	 * and exclude all these ranges while releasing memory.
 	 */
-	if (begin < ra_end && end > ra_start) {
-		if (begin < ra_start)
-			fadump_release_reserved_area(begin, ra_start);
-		if (end > ra_end)
-			fadump_release_reserved_area(ra_end, end);
-	} else
-		fadump_release_reserved_area(begin, end);
+	ret = fadump_add_mem_range(&reserved_mrange_info, ra_start, ra_end);
+	if (ret != 0) {
+		/*
+		 * Not enough memory to setup reserved ranges but the system is
+		 * running shortage of memory. So, release all the memory except
+		 * Reserved dump area (reused for next fadump registration).
+		 */
+		if (begin < ra_end && end > ra_start) {
+			if (begin < ra_start)
+				fadump_release_reserved_area(begin, ra_start);
+			if (end > ra_end)
+				fadump_release_reserved_area(ra_end, end);
+		} else
+			fadump_release_reserved_area(begin, end);
+
+		return;
+	}
+
+	/* Get the reserved ranges list in order first. */
+	sort_and_merge_mem_ranges(&reserved_mrange_info);
+
+	/* Exclude reserved ranges and release remaining memory */
+	tstart = begin;
+	for (i = 0; i < reserved_mrange_info.mem_range_cnt; i++) {
+		ra_start = reserved_mrange_info.mem_ranges[i].base;
+		ra_end = ra_start + reserved_mrange_info.mem_ranges[i].size;
+
+		if (tstart >= ra_end)
+			continue;
+
+		if (tstart < ra_start)
+			fadump_release_reserved_area(tstart, ra_start);
+		tstart = ra_end;
+	}
+
+	if (tstart < end)
+		fadump_release_reserved_area(tstart, end);
 }
 
 static void fadump_invalidate_release_mem(void)


  parent reply index

Thread overview: 74+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-20 12:04 [PATCH v5 00/31] Add FADump support on PowerNV platform Hari Bathini
2019-08-20 12:04 ` [PATCH v5 01/31] powerpc/fadump: move internal macros/definitions to a new header Hari Bathini
2019-09-03 11:09   ` Michael Ellerman
2019-09-03 16:05     ` Hari Bathini
2019-08-20 12:04 ` [PATCH v5 02/31] powerpc/fadump: move internal code to a new file Hari Bathini
2019-09-03 11:09   ` Michael Ellerman
2019-09-03 16:05     ` Hari Bathini
2019-09-04  9:02       ` Mahesh Jagannath Salgaonkar
2019-09-04 18:26         ` Hari Bathini
2019-08-20 12:04 ` [PATCH v5 03/31] powerpc/fadump: Improve fadump documentation Hari Bathini
2019-08-20 12:04 ` [PATCH v5 04/31] pseries/fadump: move rtas specific definitions to platform code Hari Bathini
2019-08-20 12:04 ` [PATCH v5 05/31] pseries/fadump: introduce callbacks for platform specific operations Hari Bathini
2019-09-03 11:10   ` Michael Ellerman
2019-09-03 16:06     ` Hari Bathini
2019-09-06  6:39       ` Hari Bathini
2019-08-20 12:04 ` [PATCH v5 06/31] pseries/fadump: define register/un-register callback functions Hari Bathini
2019-09-03 11:10   ` Michael Ellerman
2019-09-03 17:15     ` Hari Bathini
2019-08-20 12:04 ` [PATCH v5 07/31] powerpc/fadump: release all the memory above boot memory size Hari Bathini
2019-09-03 11:10   ` Michael Ellerman
2019-09-03 16:27     ` Hari Bathini
2019-08-20 12:05 ` [PATCH v5 08/31] pseries/fadump: move out platform specific support from generic code Hari Bathini
2019-08-20 12:05 ` [PATCH v5 09/31] powerpc/fadump: use FADump instead of fadump for how it is pronounced Hari Bathini
2019-08-20 12:05 ` [PATCH v5 10/31] opal: add MPIPL interface definitions Hari Bathini
2019-09-03 11:10   ` Michael Ellerman
2019-09-03 16:28     ` Hari Bathini
2019-09-04 11:03       ` Michael Ellerman
2019-09-04 11:05   ` Michael Ellerman
2019-08-20 12:05 ` [PATCH v5 11/31] powernv/fadump: add fadump support on powernv Hari Bathini
2019-09-03 11:10   ` Michael Ellerman
2019-09-03 16:31     ` Hari Bathini
2019-09-04 14:33       ` Hari Bathini
2019-09-05  3:11         ` Michael Ellerman
2019-08-20 12:05 ` [PATCH v5 12/31] powernv/fadump: register kernel metadata address with opal Hari Bathini
2019-09-04 11:25   ` Michael Ellerman
2019-08-20 12:05 ` [PATCH v5 13/31] powernv/fadump: reset metadata address during clean up Hari Bathini
2019-08-27 12:00   ` Hari Bathini
2019-08-20 12:05 ` [PATCH v5 14/31] powernv/fadump: define register/un-register callback functions Hari Bathini
2019-09-05  4:15   ` Michael Ellerman
2019-09-05  7:23   ` Michael Ellerman
2019-09-05  9:54     ` Hari Bathini
2019-08-20 12:05 ` [PATCH v5 15/31] powernv/fadump: support copying multiple kernel boot memory regions Hari Bathini
2019-09-04 11:30   ` Michael Ellerman
2019-09-04 20:20     ` Hari Bathini
2019-09-05  3:13       ` Michael Ellerman
2019-08-20 12:06 ` [PATCH v5 16/31] powernv/fadump: process the crashdump by exporting it as /proc/vmcore Hari Bathini
2019-09-04 11:42   ` Michael Ellerman
2019-09-04 21:01     ` Hari Bathini
2019-08-20 12:06 ` [PATCH v5 17/31] powernv/fadump: Warn before processing partial crashdump Hari Bathini
2019-09-04 11:48   ` Michael Ellerman
2019-08-20 12:06 ` [PATCH v5 18/31] powernv/fadump: handle invalidation of crashdump and re-registraion Hari Bathini
2019-08-20 12:06 ` [PATCH v5 19/31] powerpc/fadump: Update documentation about OPAL platform support Hari Bathini
2019-09-04 11:51   ` Michael Ellerman
2019-09-04 12:08     ` Oliver O'Halloran
2019-09-05  3:15       ` Michael Ellerman
2019-08-20 12:06 ` [PATCH v5 20/31] powerpc/fadump: use smaller offset while finding memory for reservation Hari Bathini
2019-09-04 11:54   ` Michael Ellerman
2019-08-20 12:06 ` [PATCH v5 21/31] powernv/fadump: process architected register state data provided by firmware Hari Bathini
2019-09-04 12:20   ` Michael Ellerman
2019-09-09 13:23     ` Hari Bathini
2019-09-09 15:33       ` Oliver O'Halloran
2019-09-10  8:48         ` Hari Bathini
2019-09-10 14:05           ` Michael Ellerman
2019-09-10 16:10             ` Hari Bathini
2019-08-20 12:06 ` [PATCH v5 22/31] powerpc/fadump: make crash memory ranges array allocation generic Hari Bathini
2019-08-20 12:06 ` Hari Bathini [this message]
2019-08-20 12:07 ` [PATCH v5 24/31] powerpc/fadump: improve how crashed kernel's memory is reserved Hari Bathini
2019-08-20 12:07 ` [PATCH v5 25/31] powernv/fadump: add support to preserve crash data on FADUMP disabled kernel Hari Bathini
2019-08-20 12:07 ` [PATCH v5 26/31] powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP Hari Bathini
2019-08-20 12:07 ` [PATCH v5 27/31] powernv/opalcore: export /sys/firmware/opal/core for analysing opal crashes Hari Bathini
2019-08-20 12:07 ` [PATCH v5 28/31] powernv/opalcore: provide an option to invalidate /sys/firmware/opal/core file Hari Bathini
2019-08-20 12:07 ` [PATCH v5 29/31] powerpc/fadump: consider f/w load area Hari Bathini
2019-08-20 12:07 ` [PATCH v5 30/31] powernv/fadump: update documentation about option to release opalcore Hari Bathini
2019-08-20 12:07 ` [PATCH v5 31/31] powernv/fadump: support holes in kernel boot memory area Hari Bathini

Reply instructions:

You may reply publically 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=156630281761.8896.4115696964125836702.stgit@hbathini.in.ibm.com \
    --to=hbathini@linux.ibm.com \
    --cc=ananth@linux.ibm.com \
    --cc=dja@axtens.net \
    --cc=hegdevasant@linux.ibm.com \
    --cc=linuxppc-dev@ozlabs.org \
    --cc=mahesh@linux.ibm.com \
    --cc=npiggin@gmail.com \
    --cc=oohall@gmail.com \
    /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

LinuxPPC-Dev Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linuxppc-dev/0 linuxppc-dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linuxppc-dev linuxppc-dev/ https://lore.kernel.org/linuxppc-dev \
		linuxppc-dev@lists.ozlabs.org linuxppc-dev@ozlabs.org linuxppc-dev@archiver.kernel.org
	public-inbox-index linuxppc-dev

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.ozlabs.lists.linuxppc-dev


AGPL code for this site: git clone https://public-inbox.org/ public-inbox